Search

Your search keyword '"Jason D. Eastman"' showing total 184 results
Start Over Author "Jason D. Eastman"
184 results on '"Jason D. Eastman"'

1. No Thick Atmosphere on the Terrestrial Exoplanet Gl 486b

Author

Megan Weiner Mansfield, Qiao Xue, Michael Zhang, Alexandra S. Mahajan, Jegug Ih, Daniel Koll, Jacob L. Bean, Brandon Park Coy, Jason D. Eastman, Eliza M.-R. Kempton, and Edwin S. Kite

Subjects
Exoplanets, Extrasolar rocky planets, Exoplanet atmospheres, Exoplanet surfaces, Astrophysics, QB460-466
Abstract

A primary science goal for JWST is to detect and characterize the atmospheres of terrestrial planets orbiting M dwarfs (M-Earths). The existence of atmospheres on M-Earths is highly uncertain because their host stars’ extended history of high X-ray and ultraviolet irradiation may act to completely remove their atmospheres. We present two JWST secondary eclipse observations of the M-Earth Gl 486b (also known as GJ 486b) between 5 and 12 μ m. We combined these observations with a precise analysis of the host star parameters to derive a planetary dayside temperature of T _p = 865 ± 14 K. We compared this temperature to the maximum expected temperature for a zero albedo, zero heat redistribution bare rock and derived a temperature ratio of ${ \mathcal R }=\frac{{T}_{{\rm{p}},{\rm{dayside}}}}{{T}_{{\rm{p}},{\rm{\max }}}}=0.97\pm 0.01$ . This value is consistent with an airless body with a slight nonzero albedo or a thin atmosphere with

Published
2024
Full Text
View/download PDF

2. Single-star Warm-Jupiter Systems Tend to Be Aligned, Even around Hot Stellar Hosts: No T eff–λ Dependency

Author

Xian-Yu Wang, Malena Rice, Songhu Wang, Shubham Kanodia, Fei Dai, Sarah E. Logsdon, Heidi Schweiker, Johanna K. Teske, R. Paul Butler, Jeffrey D. Crane, Stephen Shectman, Samuel N. Quinn, Veselin Kostov, Hugh P. Osborn, Robert F. Goeke, Jason D. Eastman, Avi Shporer, David Rapetti, Karen A. Collins, Cristilyn N. Watkins, Howard M. Relles, George R. Ricker, Sara Seager, Joshua N. Winn, and Jon M. Jenkins

Subjects
Planetary alignment, Exoplanet dynamics, Exoplanet evolution, Star-planet interactions, Exoplanets, Planetary theory, Astrophysics, QB460-466
Abstract

The stellar obliquity distribution of warm-Jupiter systems is crucial for constraining the dynamical history of Jovian exoplanets, as the warm Jupiters’ tidal detachment likely preserves their primordial obliquity. However, the sample size of warm-Jupiter systems with measured stellar obliquities has historically been limited compared to that of hot Jupiters, particularly in hot-star systems. In this work, we present newly obtained sky-projected stellar obliquity measurements for the warm-Jupiter systems TOI-559, TOI-2025, TOI-2031, TOI-2485, TOI-2524, and TOI-3972, derived from the Rossiter–McLaughlin effect, and show that all six systems display alignment with a median measurement uncertainty of 13°. Combining these new measurements with the set of previously reported stellar obliquity measurements, our analysis reveals that single-star warm-Jupiter systems tend to be aligned, even around hot stellar hosts. This alignment exhibits a 3.4 σ deviation from the T _eff – λ dependency observed in hot-Jupiter systems, where planets around cool stars tend to be aligned, while those orbiting hot stars show considerable misalignment. The current distribution of spin–orbit measurements for Jovian exoplanets indicates that misalignments are neither universal nor primordial phenomena affecting all types of planets. The absence of misalignments in single-star warm-Jupiter systems further implies that many hot Jupiters, by contrast, have experienced a dynamically violent history.

Published
2024
Full Text
View/download PDF

3. JWST Thermal Emission of the Terrestrial Exoplanet GJ 1132b

Author

Qiao Xue, Jacob L. Bean, Michael Zhang, Alexandra Mahajan, Jegug Ih, Jason D. Eastman, Jonathan Lunine, Megan Weiner Mansfield, Brandon Park Coy, Eliza M.-R. Kempton, Daniel Koll, and Edwin Kite

Subjects
Exoplanet astronomy, Exoplanet atmospheres, Exoplanet atmospheric composition, Exoplanet surface characteristics, Exoplanet surface composition, Astrobiology, Astrophysics, QB460-466
Abstract

We present thermal emission measurements of GJ 1132b spanning 5–12 μ m obtained with the Mid-Infrared Instrument Low-Resolution Spectrometer on the James Webb Space Telescope. GJ 1132b is an M dwarf rocky planet with T _eq = 584 K and an orbital period of 1.6 days. We measure a white-light secondary eclipse depth of 140 ± 17 ppm, which corresponds to a dayside brightness temperature of T _p _,dayside = 709 ± 31 K using improved star and planet parameters. This measured temperature is only 1 σ below the maximum possible dayside temperature of a bare rock (i.e., assuming a zero-albedo planet with no heat redistribution, ${T}_{\max }$ = ${746}_{-11}^{+14}$ K). The emission spectrum is consistent with a featureless blackbody, which agrees with a wide range of possible surface compositions. By comparing forward models to the dayside emission spectrum, we rule out Earth-thickness ( P ∼ 1 bar) atmospheres with at least 1% H _2 O, atmospheres of any modeled thickness (10 ^−4 to 10 ^2 bars) that contain at least 1% CO _2 , and thick, Venus-like atmospheres ( P ≳ 100 bars) with at least 1 ppm CO _2 or H _2 O. We therefore conclude that GJ 1132b likely does not have a significant atmosphere. This finding supports the concept of a universal “cosmic shoreline” given the high level of bolometric and extreme ultraviolet (EUV) and X-rays (collectively XUV) irradiation received by the planet.

Published
2024
Full Text
View/download PDF

4. New Insights into the Internal Structure of GJ 1214 b Informed by JWST

Author

Matthew C. Nixon, Anjali A. A. Piette, Eliza M.-R. Kempton, Peter Gao, Jacob L. Bean, Maria E. Steinrueck, Alexandra S. Mahajan, Jason D. Eastman, Michael Zhang, and Leslie A. Rogers

Subjects
Exoplanets, Mini Neptunes, Exoplanet structure, Astrophysics, QB460-466
Abstract

Recent JWST observations of the sub-Neptune GJ 1214 b suggest that it hosts a high-metallicity (≳100× solar), hazy atmosphere. Emission spectra of the planet show molecular absorption features, most likely due to atmospheric H _2 O. In light of this new information, we conduct a thorough reevaluation of the planet’s internal structure. We consider interior models with mixed H/He/H _2 O envelopes of varying composition, informed by atmospheric constraints from the JWST phase curve, in order to determine possible bulk compositions and internal structures. Self-consistent atmospheric models consistent with the JWST observations are used to set boundary conditions for the interior. We find that a total envelope mass fraction of at least 8.1% is required to explain the planet’s mass and radius. Regardless of H _2 O content, the maximum H/He mass fraction of the planet is 5.8%. We find that a 1:1 ice-to-rock ratio along with 3.4%–4.8% H/He is also a permissible solution. In addition, we consider a pure H _2 O (steam) envelope and find that such a scenario is possible, albeit with a high ice-to-rock ratio of at least 3.76:1, which may be unrealistic from a planet formation standpoint. We discuss possible formation pathways for the different internal structures that are consistent with observations. Since our results depend strongly on the atmospheric composition and haze properties, more precise observations of the planet’s atmosphere would allow for further constraints on its internal structure. This type of analysis can be applied to any sub-Neptune with atmospheric constraints to better understand its interior.

Published
2024
Full Text
View/download PDF

5. Using JWST Transits and Occultations to Determine ∼1% Stellar Radii and Temperatures of Low-mass Stars

Author

Alexandra S. Mahajan, Jason D. Eastman, and James Kirk

Subjects
Super Earths, Low mass stars, Exoplanet astronomy, Eclipses, Occultation, Astrophysics, QB460-466
Abstract

Using JWST observations of a primary transit and two secondary eclipses for GJ 1214b, we determine an eccentricity that is more precise than a decade of HARPS data, which enables us to measure the stellar density to 2.62%. Coupled with a prior on the stellar mass from a dynamically calibrated K _S – M _* relation, we determine R _* to 1.13%—3 times more precise than any other published analysis of this system. Then, using the bolometric flux from a spectral energy distribution model, we determine T _eff to 1.39%—40% more precise than systematic floors from spectroscopy. Within the global model, these also improve the planetary radius and insolation. This is a proof of concept for a new method to determine accurate R _* and T _eff to a precision currently achieved for only a small number of low-mass stars. By applying our method to all high signal-to-noise ratio planetary transits and occultations, we can expand the sample of precisely measured stars without assuming tidal circularization and calibrate new relations to improve our understanding of all low-mass stars.

Published
2024
Full Text
View/download PDF

6. Trials and Tribulations in the Reanalysis of KELT-24 b: A Case Study for the Importance of Stellar Modeling

Author

Mark R. Giovinazzi, Bryson Cale, Jason D. Eastman, Joseph E. Rodriguez, Cullen H. Blake, Keivan G. Stassun, Andrew Vanderburg, Michelle Kunimoto, Adam L. Kraus, Joseph Twicken, Thomas G. Beatty, Cayla M. Dedrick, Jonathan Horner, John A. Johnson, Samson A. Johnson, Nate McCrady, Peter Plavchan, David H. Sliski, Maurice L. Wilson, Robert A. Wittenmyer, Jason T. Wright, Marshall C. Johnson, Mark E. Rose, and Matthew Cornachione

Subjects
Exoplanet systems, Stellar properties, Multiple stars, Astronomy, QB1-991
Abstract

We present a new analysis of the KELT-24 system, comprising a well-aligned hot Jupiter, KELT-24 b, and a bright ( V = 8.3), nearby ( d = 96.9 pc) F-type host star. KELT-24 b was independently discovered by two groups in 2019, with each reporting best-fit stellar parameters that were notably inconsistent. Here, we present three independent analyses of the KELT-24 system, each incorporating a broad range of photometric and spectroscopic data, including eight sectors of Transiting Exoplanet Survey Satellite (TESS) photometry and more than 200 new radial velocities (RVs) from the MINiature Exoplanet Radial Velocity Array. Two of these analyses use KELT-24's observed spectral energy distribution (SED) through a direct comparison to stellar evolutionary models, while our third analysis assumes an unknown additional body contributing to the observed broadband photometry and excludes the SED. Ultimately, we find that the models that include the SED are a poor fit to the available data, so we adopt the system parameters derived without it. We also highlight a single transit-like event observed by TESS, deemed likely to be an eclipsing binary bound to KELT-24, that will require follow-up observations to confirm. We discuss the potential of these additional bodies in the KELT-24 system as a possible explanation for the discrepancies between the results of the different modeling approaches, and explore the system for longer-period planets that may be weakly evident in the RV observations. The comprehensive investigations that we present not only increase the fidelity of our understanding of the KELT-24 system but also serve as a blueprint for future stellar modeling in global analyses of exoplanet systems.

Published
2024
Full Text
View/download PDF

7. Migration and Evolution of giant ExoPlanets (MEEP). I. Nine Newly Confirmed Hot Jupiters from the TESS Mission

Author

Jack Schulte, Joseph E. Rodriguez, Allyson Bieryla, Samuel N. Quinn, Karen A. Collins, Samuel W. Yee, Andrew C. Nine, Melinda Soares-Furtado, David W. Latham, Jason D. Eastman, Khalid Barkaoui, David R. Ciardi, Diana Dragomir, Mark E. Everett, Steven Giacalone, Ismael Mireles, Felipe Murgas, Norio Narita, Avi Shporer, Ivan A. Strakhov, Stephanie Striegel, Martin Vaňko, Noah Vowell, Gavin Wang, Carl Ziegler, Michael Bellaver, Paul Benni, Serge Bergeron, Henri M. J. Boffin, César Briceño, Catherine A. Clark, Kevin I. Collins, Jerome P. de Leon, Courtney D. Dressing, Phil Evans, Emma Esparza-Borges, Jeremy Fedewa, Akihiko Fukui, Tianjun Gan, Ivan S. Gerasimov, Joel D. Hartman, Holden Gill, Michaël Gillon, Keith Horne, Ferran Grau Horta, Steve B. Howell, Keisuke Isogai, Emmanuël Jehin, Jon M. Jenkins, Raine Karjalainen, John F. Kielkopf, Kathryn V. Lester, Colin Littlefield, Michael B. Lund, Andrew W. Mann, Mason McCormack, Edward J. Michaels, Shane Painter, Enric Palle, Hannu Parviainen, David-Michael Peterson, Francisco J. Pozuelos, Zachary Raup, Phillip Reed, Howard M. Relles, George R. Ricker, Arjun B. Savel, Richard P. Schwarz, S. Seager, Ramotholo Sefako, Gregor Srdoc, Chris Stockdale, Hannah Sullivan, Mathilde Timmermans, and Joshua N. Winn

Subjects
Exoplanet astronomy, Exoplanet migration, Exoplanet detection methods, Exoplanets, Transits, Radial velocity, Astronomy, QB1-991
Abstract

Hot Jupiters were many of the first exoplanets discovered in the 1990s, but in the decades since their discovery the mysteries surrounding their origins have remained. Here we present nine new hot Jupiters (TOI-1855 b, TOI-2107 b, TOI-2368 b, TOI-3321 b, TOI-3894 b, TOI-3919 b, TOI-4153 b, TOI-5232 b, and TOI-5301 b) discovered by NASA’s TESS mission and confirmed using ground-based imaging and spectroscopy. These discoveries are the first in a series of papers named the Migration and Evolution of giant ExoPlanets survey and are part of an ongoing effort to build a complete sample of hot Jupiters orbiting FGK stars, with a limiting Gaia G -band magnitude of 12.5. This effort aims to use homogeneous detection and analysis techniques to generate a set of precisely measured stellar and planetary properties that is ripe for statistical analysis. The nine planets presented in this work occupy a range of masses (0.55 M _J < M _P < 3.88 M _J ) and sizes (0.967 R _J < R _P < 1.438 R _J ) and orbit stars that have an effective temperature in the range of 5360 K < T _eff < 6860 K with Gaia G -band magnitudes ranging from 11.1 to 12.7. Two of the planets in our sample have detectable orbital eccentricity: TOI-3919 b ( $e={0.259}_{-0.036}^{+0.033}$ ) and TOI-5301 b ( $e={0.33}_{-0.10}^{+0.11}$ ). These eccentric planets join a growing sample of eccentric hot Jupiters that are consistent with high-eccentricity tidal migration, one of the three most prominent theories explaining hot Jupiter formation and evolution.

Published
2024
Full Text
View/download PDF

8. The TESS–Keck Survey. XIX. A Warm Transiting Sub-Saturn-mass Planet and a Nontransiting Saturn-mass Planet Orbiting a Solar Analog

Author

Michelle L. Hill, Stephen R. Kane, Paul A. Dalba, Mason MacDougall, Tara Fetherolf, Zhexing Li, Daria Pidhorodetska, Natalie M. Batalha, Ian J. M. Crossfield, Courtney Dressing, Benjamin Fulton, Andrew W. Howard, Daniel Huber, Howard Isaacson, Erik A. Petigura, Paul Robertson, Lauren M. Weiss, Aida Behmard, Corey Beard, Ashley Chontos, Fei Dai, Steven Giacalone, Lea A. Hirsch, Rae Holcomb, Jack Lubin, Andrew W. Mayo, Teo Močnik, Joseph M. Akana Murphy, Alex S. Polanski, Lee J. Rosenthal, Ryan A. Rubenzahl, Nicholas Scarsdale, Emma V. Turtelboom, Judah Van Zandt, Allyson Bieryla, David R. Ciardi, Jason D. Eastman, Ben Falk, Katharine M. Hesse, David W. Latham, John Livingston, Rachel A. Matson, Elisabeth Matthews, George R. Ricker, Alexander Rudat, Joshua E. Schlieder, S. Seager, and Joshua N. Winn

Subjects
Exoplanets, Exoplanet astronomy, Exoplanet detection methods, Radial velocity, Transit photometry, Photometry, Astronomy, QB1-991
Abstract

The Transiting Exoplanet Survey Satellite (TESS) continues to increase dramatically the number of known transiting exoplanets, and is optimal for monitoring bright stars amenable to radial velocity (RV) and atmospheric follow-up observations. TOI-1386 is a solar-type (G5V) star that was detected via TESS photometry to exhibit transit signatures in three sectors with a period of 25.84 days. We conducted follow-up RV observations using Keck/High Resolution Echelle Spectrometer (HIRES) as part of the TESS–Keck Survey, collecting 64 RV measurements of TOI-1386 with the HIRES spectrograph over 2.5 yr. Our combined fit of the TOI-1386 photometry and RV data confirm the planetary nature of the detected TESS signal, and provide a mass and radius for planet b of 0.148 ± 0.019 M _J and 0.540 ± 0.017 R _J , respectively, marking TOI-1386 b as a warm sub-Saturn planet. Our RV data further reveal an additional outer companion, TOI-1386 c, with an estimated orbital period of 227.6 days and a minimum mass of 0.309 ± 0.038 M _J . The dynamical modeling of the system shows that the measured system architecture is long-term stable, although there may be substantial eccentricity oscillations of the inner planet due to the dynamical influence of the outer planet.

Published
2024
Full Text
View/download PDF

9. TOI-3235 b: A Transiting Giant Planet around an M4 Dwarf Star

Author

Melissa J. Hobson, Andrés Jordán, E. M. Bryant, R. Brahm, D. Bayliss, J. D. Hartman, G. Á. Bakos, Th. Henning, Jose Manuel Almenara, Khalid Barkaoui, Zouhair Benkhaldoun, Xavier Bonfils, François Bouchy, David Charbonneau, Marion Cointepas, Karen A. Collins, Jason D. Eastman, Mourad Ghachoui, Michaël Gillon, Robert F. Goeke, Keith Horne, Jonathan M. Irwin, Emmanuel Jehin, Jon M. Jenkins, David W. Latham, Dan Moldovan, Felipe Murgas, Francisco J. Pozuelos, George R. Ricker, Richard P. Schwarz, S. Seager, Gregor Srdoc, Stephanie Striegel, Mathilde Timmermans, Andrew Vanderburg, Roland Vanderspek, and Joshua N. Winn

Subjects
Exoplanets, Transit photometry, Radial velocity, M dwarf stars, Astrophysics, QB460-466
Abstract

We present the discovery of TOI-3235 b, a short-period Jupiter orbiting an M dwarf with a stellar mass close to the critical mass at which stars transition from partially to fully convective. TOI-3235 b was first identified as a candidate from TESS photometry and confirmed with radial velocities from ESPRESSO and ground-based photometry from HATSouth, MEarth-South, TRAPPIST-South, LCOGT, and ExTrA. We find that the planet has a mass of 0.665 ± 0.025 M _J and a radius of 1.017 ± 0.044 R _J . It orbits close to its host star, with an orbital period of 2.5926 days but has an equilibrium temperature of ≈ 604 K, well below the expected threshold for radius inflation of hot Jupiters. The host star has a mass of 0.3939 ± 0.0030 M _☉ , a radius of 0.3697 ± 0.0018 R _☉ , an effective temperature of 3389 K, and a J -band magnitude of 11.706 ± 0.025. Current planet formation models do not predict the existence of gas giants such as TOI-3235 b around such low-mass stars. With a high transmission spectroscopy metric, TOI-3235 b is one of the best-suited giants orbiting M dwarfs for atmospheric characterization.

Published
2023
Full Text
View/download PDF

10. Giant Outer Transiting Exoplanet Mass (GOT ’EM) Survey. III. Recovery and Confirmation of a Temperate, Mildly Eccentric, Single-transit Jupiter Orbiting TOI-2010

Author

Christopher R. Mann, Paul A. Dalba, David Lafrenière, Benjamin J. Fulton, Guillaume Hébrard, Isabelle Boisse, Shweta Dalal, Magali Deleuil, Xavier Delfosse, Olivier Demangeon, Thierry Forveille, Neda Heidari, Flavien Kiefer, Eder Martioli, Claire Moutou, Michael Endl, William D. Cochran, Phillip MacQueen, Franck Marchis, Diana Dragomir, Arvind F. Gupta, Dax L. Feliz, Belinda A. Nicholson, Carl Ziegler, Steven Villanueva Jr., Jason Rowe, Geert Jan Talens, Daniel Thorngren, Daryll LaCourse, Tom Jacobs, Andrew W. Howard, Allyson Bieryla, David W. Latham, Markus Rabus, Tara Fetherolf, Coel Hellier, Steve B. Howell, Peter Plavchan, Michael Reefe, Deven Combs, Michael Bowen, Justin Wittrock, George R. Ricker, S. Seager, Joshua N. Winn, Jon M. Jenkins, Thomas Barclay, David Watanabe, Karen A. Collins, Jason D. Eastman, and Eric B. Ting

Subjects
Exoplanet astronomy, Exoplanet systems, Exoplanet dynamics, Exoplanet detection methods, Astronomy, QB1-991
Abstract

Large-scale exoplanet surveys like the Transiting Exoplanet Survey Satellite (TESS) mission are powerful tools for discovering large numbers of exoplanet candidates. Single-transit events are commonplace within the resulting candidate list due to the unavoidable limitation of the observing baseline. These single-transit planets often remain unverified due to their unknown orbital periods and consequent difficulty in scheduling follow-up observations. In some cases, radial velocity (RV) follow up can constrain the period enough to enable a future targeted transit detection. We present the confirmation of one such planet: TOI-2010 b. Nearly three years of RV coverage determined the period to a level where a broad window search could be undertaken with the Near-Earth Object Surveillance Satellite, detecting an additional transit. An additional detection in a much later TESS sector solidified our final parameter estimation. We find TOI-2010 b to be a Jovian planet ( M _P = 1.29 M _Jup , R _P = 1.05 R _Jup ) on a mildly eccentric orbit ( e = 0.21) with a period of P = 141.83403 days. Assuming a simple model with no albedo and perfect heat redistribution, the equilibrium temperature ranges from about 360 to 450 K from apastron to periastron. Its wide orbit and bright host star ( V = 9.85) make TOI-2010 b a valuable test bed for future low-insolation atmospheric analysis.

Published
2023
Full Text
View/download PDF

11. TESS Spots a Super-puff: The Remarkably Low Density of TOI-1420b

Author

Stephanie Yoshida, Shreyas Vissapragada, David W. Latham, Allyson Bieryla, Daniel P. Thorngren, Jason D. Eastman, Mercedes López-Morales, Khalid Barkaoui, Charles Beichman, Perry Berlind, Lars A. Buchave, Michael L. Calkins, David R. Ciardi, Karen A. Collins, Rosario Cosentino, Ian J. M. Crossfield, Fei Dai, Victoria DiTomasso, Nicholas Dowling, Gilbert A. Esquerdo, Raquel Forés-Toribio, Adriano Ghedina, Maria V. Goliguzova, Eli Golub, Erica J. Gonzales, Ferran Grau Horta, Jesus Higuera, Nora Hoch, Keith Horne, Steve B. Howell, Jon M. Jenkins, Jessica Klusmeyer, Didier Laloum, Jack J. Lissauer, Sarah E. Logsdon, Luca Malavolta, Rachel A. Matson, Elisabeth C. Matthews, Kim K. McLeod, Jennifer V. Medina, Jose A. Muñoz, Hugh P. Osborn, Boris Safonov, Joshua Schlieder, Michael Schmidt, Heidi Schweiker, Sara Seager, Alessandro Sozzetti, Gregor Srdoc, Guđmundur Stefánsson, Ivan A. Strakhov, Stephanie Striegel, Joel Villaseñor, and Joshua N. Winn

Subjects
Exoplanets, Transits, Exoplanet structure, Astronomy, QB1-991
Abstract

We present the discovery of TOI-1420b, an exceptionally low-density ( ρ = 0.08 ± 0.02 g cm ^−3 ) transiting planet in a P = 6.96 days orbit around a late G-dwarf star. Using transit observations from TESS, LCOGT, Observatoire Privé du Mont, Whitin, Wendelstein, OAUV, Ca l’Ou, and KeplerCam, along with radial velocity observations from HARPS-N and NEID, we find that the planet has a radius of R _p = 11.9 ± 0.3 R _⊕ and a mass of M _p = 25.1 ± 3.8 M _⊕ . TOI-1420b is the largest known planet with a mass less than 50 M _⊕ , indicating that it contains a sizeable envelope of hydrogen and helium. We determine TOI-1420b’s envelope mass fraction to be ${f}_{\mathrm{env}}={82}_{-6}^{+7} \% $ , suggesting that runaway gas accretion occurred when its core was at most four to five times the mass of the Earth. TOI-1420b is similar to the planet WASP-107b in mass, radius, density, and orbital period, so a comparison of these two systems may help reveal the origins of close-in low-density planets. With an atmospheric scale height of 1950 km, a transmission spectroscopy metric of 580, and a predicted Rossiter–McLaughlin amplitude of about 17 m s ^−1 , TOI-1420b is an excellent target for future atmospheric and dynamical characterization.

Published
2023
Full Text
View/download PDF

12. HST/WFC3 Light Curve Supports a Terrestrial Composition for the Closest Exoplanet to Transit an M Dwarf

Author

Emily K. Pass, Jennifer G. Winters, David Charbonneau, Aurelia Balkanski, Nikole Lewis, Maura Lally, Jacob L. Bean, Ryan Cloutier, and Jason D. Eastman

Subjects
Exoplanet astronomy, Transit photometry, Exoplanets, M dwarf stars, Transits, HST photometry, Astronomy, QB1-991
Abstract

Previous studies of the exoplanet LTT 1445Ac concluded that the light curve from the Transiting Exoplanet Survey Satellite (TESS) was consistent with both grazing and nongrazing geometries. As a result, the radius and hence density of the planet remained unknown. To resolve this ambiguity, we observed the LTT 1445 system for six spacecraft orbits of the Hubble Space Telescope (HST) using WFC3/UVIS imaging in spatial scan mode, including one partial transit of LTT 1445Ac. This imaging produces resolved light curves of each of the three stars in the LTT 1445 system. We confirm that the planet transits LTT 1445A and that LTT 1445C is the source of the rotational modulation seen in the TESS light curve, and we refine the estimate of the dilution factor for the TESS data. We perform a joint fit to the TESS and HST observations, finding that the transit of LTT 1445Ac is not grazing with 97% confidence. We measure a planetary radius of ${1.07}_{-0.07}^{+0.10}\,{R}_{\oplus }$ . Combined with previous radial velocity observations, our analysis yields a planetary mass of 1.37 ± 0.19 M _⊕ and a planetary density of ${5.9}_{-1.5}^{+1.8}$ g cm ^−3 . LTT 1445Ac is likely an Earth analog with respect to its mass and radius, albeit with a higher instellation, and is therefore an exciting target for future atmospheric studies.

Published
2023
Full Text
View/download PDF

13. Beating Stellar Systematic Error Floors Using Transit-based Densities

Author

Jason D. Eastman, Hannah Diamond-Lowe, and Jamie Tayar

Subjects
Exoplanet astronomy, Planet hosting stars, Stellar evolutionary models, Spectral energy distribution, Measurement error model, Exoplanet detection methods, Astronomy, QB1-991
Abstract

It has long been understood that the light curve of a transiting planet constrains the density of its host star. That fact is routinely used to improve measurements of the stellar surface gravity and has been argued to be an independent check on the stellar mass. Here we show how the stellar density can also dramatically improve the precision of the radius and effective temperature of the star. This additional constraint is especially significant when we properly account for the 4.2% radius and 2.0% temperature systematic errors inherited from photometric zero-points, model atmospheres, interferometric calibration, and extinction. In the typical case, we can constrain stellar radii to 3% and temperatures to 1.75% with our evolutionary-model-based technique. In the best real-world cases, we can infer radii to 1.6% and temperatures to 1.1%—well below the systematic measurement floors—which can improve the precision in the planetary parameters by a factor of two. We explain in detail the mechanism that makes it possible and show a demonstration of the technique for a near-ideal system, WASP-4. We also show that both the statistical and systematic uncertainties in the parallax from Gaia DR3 are often a significant component of the uncertainty in L _* and must be treated carefully. Taking advantage of our technique requires simultaneous models of the stellar evolution, bolometric flux (e.g., a stellar spectral energy distribution), and the planetary transit, while accounting for the systematic errors in each, as is done in EXOFASTv2.

Published
2023
Full Text
View/download PDF

14. HIP 33609 b: An Eccentric Brown Dwarf Transiting a V = 7.3 Rapidly Rotating B Star

Author

Noah Vowell, Joseph E. Rodriguez, Samuel N. Quinn, George Zhou, Andrew Vanderburg, Andrew W. Mann, Matthew J. Hooton, Keivan G. Stassun, Saburo Howard, Allyson Bieryla, David W. Latham, Steve B. Howell, Tristan Guillot, Carl Ziegler, Karen A. Collins, Theron W. Carmichael, Jon M. Jenkins, Avi Shporer, Lyu ABE, Philippe Bendjoya, Jonathan L. Bush, Marco Buttu, Kevin I. Collins, Jason D. Eastman, Matthew J. Fields, Thomas Gasparetto, Maximilian N. Günther, Veselin B. Kostov, Adam L. Kraus, Kathryn V. Lester, Alan M. Levine, Colin Littlefield, Wenceslas Marie-Sainte, Djamel Mékarnia, Hugh P. Osborn, David Rapetti, George R. Ricker, S. Seager, Ramotholo Sefako, Gregor Srdoc, Olga Suarez, Guillermo Torres, Amaury H. M. J. Triaud, R. Vanderspek, and Joshua N. Winn

Subjects
Exoplanets, Brown dwarfs, Young star clusters, Direct imaging, CCD photometry, High resolution spectroscopy, Astronomy, QB1-991
Abstract

We present the discovery and characterization of HIP 33609 b, a transiting warm brown dwarf orbiting a late B star, discovered by NASA's Transiting Exoplanet Survey Satellite as TOI-588 b. HIP 33609 b is a large ( R _b = ${1.580}_{-0.070}^{+0.074}$ R _J ) brown dwarf on a highly eccentric ( e = ${0.560}_{-0.031}^{+0.029}$ ) orbit with a 39 days period. The host star is a bright ( V = 7.3 mag), T _eff = 10,400 ${}_{-660}^{+800}$ K star with a mass of M _* = ${2.383}_{-0.095}^{+0.10}$ M _⊙ and radius of R _* = ${1.863}_{-0.082}^{+0.087}$ R _⊙ , making it the hottest transiting brown dwarf host star discovered to date. We obtained radial velocity measurements from the CHIRON spectrograph confirming the companion's mass of M _b = ${68.0}_{-7.1}^{+7.4}$ M _J as well as the host star's rotation rate ( $v\sin {i}_{* }=55.6\pm 1.8$ km s ^−1 ). We also present the discovery of a new comoving group of stars, designated as MELANGE-6, and determine that HIP 33609 is a member. We use a combination of rotation periods and isochrone models fit to the cluster members to estimate an age of 150 ± 25 Myr. With a measured mass, radius, and age, HIP 33609 b becomes a benchmark for substellar evolutionary models.

Published
2023
Full Text
View/download PDF

15. The K2 and TESS Synergy. II. Revisiting 26 Systems in the TESS Primary Mission

Author

Erica Thygesen, Jessica A. Ranshaw, Joseph E. Rodriguez, Andrew Vanderburg, Samuel N. Quinn, Jason D. Eastman, Allyson Bieryla, David W. Latham, Roland K. Vanderspek, Jon M. Jenkins, Douglas A. Caldwell, Mma Ikwut-Ukwa, Knicole D. Colón, Jessie Dotson, Christina Hedges, Karen A. Collins, Michael L. Calkins, Perry Berlind, and Gilbert A. Esquerdo

Subjects
Exoplanet catalogs, Exoplanet astronomy, Exoplanet systems, Exoplanets, Ephemerides, Astronomy, QB1-991
Abstract

The legacy of NASA’s K2 mission has provided hundreds of transiting exoplanets that can be revisited by new and future facilities for further characterization, with a particular focus on studying the atmospheres of these systems. However, the majority of K2-discovered exoplanets have typical uncertainties on future times of transit within the next decade of greater than 4 hr, making observations less practical for many upcoming facilities. Fortunately, NASA’s Transiting Exoplanet Survey Satellite (TESS) mission is reobserving most of the sky, providing the opportunity to update the ephemerides for ∼300 K2 systems. In the second paper of this series, we reanalyze 26 single-planet, K2-discovered systems that were observed in the TESS primary mission by globally fitting their K2 and TESS light curves (including extended mission data where available), along with any archival radial velocity measurements. As a result of the faintness of the K2 sample, 13 systems studied here do not have transits detectable by TESS. In those cases, we refit the K2 light curve and provide updated system parameters. For the 23 systems with M _* ≳ 0.6 M _⊙ , we determine the host star parameters using a combination of Gaia parallaxes, spectral energy distribution fits, and MESA Isochrones and Stellar Tracks stellar evolution models. Given the expectation of future TESS extended missions, efforts like the K2 and TESS Synergy project will ensure the accessibility of transiting planets for future characterization while leading to a self-consistent catalog of stellar and planetary parameters for future population efforts.

Published
2023
Full Text
View/download PDF

16. Erratum: 'TESS Hunt for Young and Maturing Exoplanets (THYME). VII. Membership, Rotation, and Lithium in the Young Cluster Group-X and a New Young Exoplanet' (2022, AJ, 164, 119)

Author

Elisabeth R. Newton, Rayna Rampalli, Adam L. Kraus, Andrew W. Mann, Jason L. Curtis, Andrew Vanderburg, Daniel M. Krolikowski, Daniel Huber, Grayson C. Petter, Allyson Bieryla, Benjamin M. Tofflemire, Pa Chia Thao, Mackenna L. Wood, Ronan Kerr, Boris S. Safanov, Ivan A. Strakhov, David R. Ciardi, Steven Giacalone, Courtney D. Dressing, Holden Gill, Arjun B. Savel, Karen A. Collins, Peyton Brown, Felipe Murgas, Keisuke Isogai, Norio Narita, Enric Palle, Samuel N. Quinn, Jason D. Eastman, Gábor Fűrész, Bernie Shiao, Tansu Daylan, Douglas A. Caldwell, George R. Ricker, Roland Vanderspek, Sara Seager, Joshua N. Winn, Jon M. Jenkins, and David W. Latham

Subjects
Astronomy, QB1-991
Published
2023
Full Text
View/download PDF

17. The TESS Grand Unified Hot Jupiter Survey. II. Twenty New Giant Planets

Author

Samuel W. Yee, Joshua N. Winn, Joel D. Hartman, Luke G. Bouma, George Zhou, Samuel N. Quinn, David W. Latham, Allyson Bieryla, Joseph E. Rodriguez, Karen A. Collins, Owen Alfaro, Khalid Barkaoui, Corey Beard, Alexander A. Belinski, Zouhair Benkhaldoun, Paul Benni, Krzysztof Bernacki, Andrew W. Boyle, R. Paul Butler, Douglas A. Caldwell, Ashley Chontos, Jessie L. Christiansen, David R. Ciardi, Kevin I. Collins, Dennis M. Conti, Jeffrey D. Crane, Tansu Daylan, Courtney D. Dressing, Jason D. Eastman, Zahra Essack, Phil Evans, Mark E. Everett, Sergio Fajardo-Acosta, Raquel Forés-Toribio, Elise Furlan, Mourad Ghachoui, Michaël Gillon, Coel Hellier, Ian Helm, Andrew W. Howard, Steve B. Howell, Howard Isaacson, Emmanuel Jehin, Jon M. Jenkins, Eric L. N. Jensen, John F. Kielkopf, Didier Laloum, Naunet Leonhardes-Barboza, Pablo Lewin, Sarah E. Logsdon, Jack Lubin, Michael B. Lund, Mason G. MacDougall, Andrew W. Mann, Natalia A. Maslennikova, Bob Massey, Kim K. McLeod, Jose A. Muñoz, Patrick Newman, Valeri Orlov, Peter Plavchan, Adam Popowicz, Francisco J. Pozuelos, Tyler A. Pritchard, Don J. Radford, Michael Reefe, George R. Ricker, Alexander Rudat, Boris S. Safonov, Richard P. Schwarz, Heidi Schweiker, Nicholas J. Scott, S. Seager, Stephen A. Shectman, Chris Stockdale, Thiam-Guan Tan, Johanna K. Teske, Neil B. Thomas, Mathilde Timmermans, Roland Vanderspek, David Vermilion, David Watanabe, Lauren M. Weiss, Richard G. West, Judah Van Zandt, Michal Zejmo, and Carl Ziegler

Subjects
Exoplanets, Hot Jupiters, Radial velocity, Exoplanet detection methods, Transit photometry, Astrophysics, QB460-466
Abstract

NASA’s Transiting Exoplanet Survey Satellite (TESS) mission promises to improve our understanding of hot Jupiters by providing an all-sky, magnitude-limited sample of transiting hot Jupiters suitable for population studies. Assembling such a sample requires confirming hundreds of planet candidates with additional follow-up observations. Here we present 20 hot Jupiters that were detected using TESS data and confirmed to be planets through photometric, spectroscopic, and imaging observations coordinated by the TESS Follow-up Observing Program. These 20 planets have orbital periods shorter than 7 days and orbit relatively bright FGK stars (10.9 < G < 13.0). Most of the planets are comparable in mass to Jupiter, although there are four planets with masses less than that of Saturn. TOI-3976b, the longest-period planet in our sample ( P = 6.6 days), may be on a moderately eccentric orbit ( e = 0.18 ± 0.06), while observations of the other targets are consistent with them being on circular orbits. We measured the projected stellar obliquity of TOI-1937A b, a hot Jupiter on a 22.4 hr orbit with the Rossiter–McLaughlin effect, finding the planet’s orbit to be well aligned with the stellar spin axis (∣ λ ∣ = 4.°0 ± 3.°5). We also investigated the possibility that TOI-1937 is a member of the NGC 2516 open cluster but ultimately found the evidence for cluster membership to be ambiguous. These objects are part of a larger effort to build a complete sample of hot Jupiters to be used for future demographic and detailed characterization work.

Published
2023
Full Text
View/download PDF

18. TESS Hunt for Young and Maturing Exoplanets (THYME). VII. Membership, Rotation, and Lithium in the Young Cluster Group-X and a New Young Exoplanet

Author

Elisabeth R. Newton, Rayna Rampalli, Adam L. Kraus, Andrew W. Mann, Jason L. Curtis, Andrew Vanderburg, Daniel M. Krolikowski, Daniel Huber, Grayson C. Petter, Allyson Bieryla, Benjamin M. Tofflemire, Pa Chia Thao, Mackenna L. Wood, Ronan Kerr, Boris S. Safanov, Ivan A. Strakhov, David R. Ciardi, Steven Giacalone, Courtney D. Dressing, Holden Gill, Arjun B. Savel, Karen A. Collins, Peyton Brown, Felipe Murgas, Keisuke Isogai, Norio Narita, Enric Palle, Samuel N. Quinn, Jason D. Eastman, Gábor Fűrész, Bernie Shiao, Tansu Daylan, Douglas A. Caldwell, George R. Ricker, Roland Vanderspek, Sara Seager, Joshua N. Winn, Jon M. Jenkins, and David W. Latham

Subjects
Young star clusters, Stellar rotation, Exoplanets, Astronomy, QB1-991
Abstract

The public, all-sky surveys Gaia and TESS provide the ability to identify new young associations and determine their ages. These associations enable study of planetary evolution by providing new opportunities to discover young exoplanets. A young association was recently identified by Tang et al. and Fürnkranz et al. using astrometry from Gaia (called “Group-X” by the former). In this work, we investigate the age and membership of this association, and we validate the exoplanet TOI 2048 b, which was identified to transit a young, late G dwarf in Group-X using photometry from TESS. We first identified new candidate members of Group-X using Gaia EDR3 data. To infer the age of the association, we measured rotation periods for candidate members using TESS data. The clear color–period sequence indicates that the association is the same age as the 300 ± 50 Myr old NGC 3532. We obtained optical spectra for candidate members that show lithium absorption consistent with this young age. Further, we serendipitously identify a new, small association nearby Group-X, which we call MELANGE-2. Lastly, we statistically validate TOI 2048 b, which is a 2.1 ± 0.2 R _⊕ radius planet on a 13.8-day orbit around its 300 Myr old host star.

Published
2022
Full Text
View/download PDF

19. Transit Timing Variations for AU Microscopii b and c

Author

Justin M Wittrock, Stefan Dreizler, Michael A Reefe, Brett M Morris, Peter P Plavchan, Patrick J Lowrance, Brice-Olivier Demory, James G Ingalls, Emily A Gilbert, Thomas Barclay, Bryson L Cale, Karen A Collins, Kevin I Collins, Ian J M Crossfield, Diana Dragomir, Jason D Eastman, Mohammed El Mufti, Dax Felix, Jonathan Gagné, Eric Gaidos, Peter Gao, Claire S Geneser, Leslie Hebb, Christopher E Henze, Keith D Horne, Jon M Jenkins, Eric L N Jensen, Stephen R Kane, Laurel Kaye, Eder Martioli, Teresa Monsue, Enric Pallé, Elisa V Quintana, Don J Radford, Veronica Roccatagliata, Joshua E Schlieder, Richard P Schwarz, Avi Shporer, Keivan G Stassun, Christopher Stockdale, Thiam-Guan Tan, Angelle M Tanner, Andrew M Vanderburg, Laura D Vega, and Songhu Wang

Subjects
Astronomy
Abstract

We explore the transit timing variations (TTVs) of the young (22 Myr) nearby AU Mic planetary system. For AU Mic b, we introduce three Spitzer (4.5 μm) transits, five TESS transits, 11 LCO transits, one PEST transit, one Brierfield transit, and two transit timing measurements from Rossiter–McLaughlin observations; for AU Mic c, we introduce three TESS transits. We present two independent TTV analyses. First, we use EXOFASTv2 to jointly model the Spitzer and ground-based transits and obtain the midpoint transit times. We then construct an O − C diagram and model the TTVs with Exo-Striker. Second, we reproduce our results with an independent photodynamical analysis. We recover a TTV mass for AU Mic c of -10.8+2.22.3 M⊕. We compare the TTV-derived constraints to a recent radial velocity (RV) mass determination. We also observe excess TTVs that do not appear to be consistent with the dynamical interactions of b and c alone or due to spots or flares. Thus, we present a hypothetical nontransiting “middle-d” candidate exoplanet that is consistent with the observed TTVs and candidate RV signal and would establish the AU Mic system as a compact resonant multiplanet chain in a 4:6:9 period commensurability. These results demonstrate that the AU Mic planetary system is dynamically interacting, producing detectable TTVs, and the implied orbital dynamics may inform the formation mechanisms for this young system. We recommend future RV and TTV observations of AU Mic b and c to further constrain the masses and confirm the existence of possible additional planet(s).

Published
2022
Full Text
View/download PDF

20. Populating the brown dwarf and stellar boundary: Five stars with transiting companions near the hydrogen-burning mass limit

Author

Nolan Grieves, François Bouchy, Monika Lendl, Theron Carmichael, Ismael Mireles, Avi Shporer, Kim K. McLeod, Karen A. Collins, Rafael Brahm, Keivan G. Stassun, Sam Gill, Luke G. Bouma, Tristan Guillot, Marion Cointepas, Leonardo A. Dos Santos, Sarah L. Casewell, Jon M. Jenkins, Thomas Henning, Louise D. Nielsen, Angelica Psaridi, Stéphane Udry, Damien Ségransan, Jason D. Eastman, George Zhou, Lyu Abe, Abelkrim Agabi, Gaspar Bakos, David Charbonneau, Kevin I. Collins, Knicole D. Colon, Nicolas Crouzet, Georgina Dransfield, Phil Evans, Robert F. Goeke, Rhodes Hart, Jonathan M. Irwin, Eric L. N. Jensen, Andrés Jordán, John F. Kielkopf, David W. Latham, Wenceslas Marie-Sainte, Djamel Mékarnia, Peter Nelson, Samuel N. Quinn, Don J. Radford, David R. Rodriguez, Pamela Rowden, François–Xavier Schmider, Richard P. Schwarz, Jeffrey C. Smith, Chris Stockdale, Olga Suarez, Thiam-Guan Tan, Amaury H. M. J. Triaud, William Waalkes, and Geof Wingham

Subjects
Astrophysics
Abstract

We report the discovery of five transiting companions near the hydrogen-burning mass limit in close orbits around main sequence stars originally identified by the Transiting Exoplanet Survey Satellite (TESS) as TESS objects of interest (TOIs): TOI-148, TOI-587, TOI-681, TOI-746, and TOI-1213. Using TESS and ground-based photometry as well as radial velocities from the CORALIE, CHIRON, TRES, and FEROS spectrographs, we found the companions have orbital periods between 4.8 and 27.2 days, masses between 77 and 98 MJup , and radii between 0.81 and 1.66 RJup . These targets have masses near the uncertain lower limit of hydrogen core fusion (~73-96 MJup ), which separates brown dwarfs and low-mass stars. We constrained young ages for TOI-587 (0.2 ± 0.1 Gyr) and TOI-681 (0.17 ± 0.03 Gyr) and found them to have relatively larger radii compared to other transiting companions of a similar mass. Conversely we estimated older ages for TOI-148 and TOI-746 and found them to have relatively smaller companion radii. With an effective temperature of 9800 ± 200 K, TOI-587 is the hottest known main-sequence star to host a transiting brown dwarf or very low-mass star. We found evidence of spin-orbit synchronization for TOI-148 and TOI-746 as well as tidal circularization for TOI-148. These companions add to the population of brown dwarfs and very low-mass stars with well measured parameters ideal to test formation models of these rare objects, the origin of the brown dwarf desert, and the distinction between brown dwarfs and hydrogen-burning main sequence stars.

Published
2021
Full Text
View/download PDF

21. TOI-1231 b: A Temperate, Neptune-sized Planet Transiting the Nearby M3 Dwarf NLTT 24399

Author

Jennifer A. Burt, Diana Dragomir, Paul Mollière, Allison Ann Youngblood, Antonio García Muñoz, John McCann, Laura Kreidberg, Chelsea X. Huang, Karen A. Collins, Jason D. Eastman, Lyu Abe, Jose M. Almenara, Ian J. M. Crossfield, Carl Ziegler, Joseph E. Rodriguez, Eric E. Mamajek, Keivan G. Stassun, Samuel P. Halverson, Steven Villanueva Jr, R. Paul Butler, Sharon Xuesong Wang, Richard P Schwarz, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Abdelkrim Agabi, Xavier Bonfils, David Ciardi, Marion Cointepas, Jeffrey D. Crane, Nicolas Crouzet, Georgina Dransfield, Fabo Feng, Elise Furlan, Tristan Guillot, Arvind F. Gupta, Steve B. Howell, Eric L. N. Jensen, Nicholas Law, Andrew W. Mann, Wenceslas Marie-Sainte, Rachel A. Matson, Elisabeth C. Matthews, Djamel Mékarnia, Joshua Pepper, Nic Scott, Stephen A. Shectman, Joshua E. Schlieder, François-Xavier Schmider, Daniel J. Stevens, Johanna K. Teske, Amaury H. M. J. Triaud, David Charbonneau, Zachory K. Berta-Thompson, Christopher J. Burke, Tansu Daylan, Thomas Barclay, Bill Wohler, and C. E. Brasseur

Subjects
Astronomy, Astrophysics
Abstract

We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby (d = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite and followed up with observations from the Las Cumbres Observatory and the Antarctica Search for Transiting ExoPlanets program. Combining the photometric data sets, we find that the newly discovered planet has a radius of 3.65(+0.16,-0.15)Rꚛ and an orbital period of 24.246 days. Radial velocity measurements obtained with the Planet Finder Spectrograph on the Magellan Clay telescope confirm the existence of the planet and lead to a mass measurement of 15.5 ± 3.3 Mꚛ. With an equilibrium temperature of just 330 K, TOI-1231 b is one of the coolest small planets accessible for atmospheric studies thus far, and its host star's bright near-infrared brightness (J = 8.88, Ks = 8.07) makes it an exciting target for the Hubble Space Telescope and the James Webb Space Telescope. Future atmospheric observations would enable the first comparative planetology efforts in the 250–350 K temperature regime via comparisons with K2-18 b. Furthermore, TOI-1231's high systemic radial velocity (70.5 km/s) may allow for the detection of low-velocity hydrogen atoms escaping the planet by Doppler, shifting the H i Lyα stellar emission away from the geocoronal and interstellar medium absorption features.

Published
2021
Full Text
View/download PDF

22. Another shipment of six short-period giant planets from TESS

Author

Joseph E Rodriguez, Samuel N Quinn, Andrew Vanderburg, George Zhou, Jason D Eastman, Erica Thygesen, Bryson Cale, David R Ciardi, Phillip A Reed, Ryan J Oelkers, Karen A Collins, Allyson Bieryla, David W Latham, Erica J Gonzales, B Scott Gaudi, Coel Hellier, Matías I Jones, Rafael Brahm, Kirill Sokolovsky, Jack Schulte, Gregor Srdoc, John Kielkopf, Ferran Grau Horta, Bob Massey, Phil Evans, Denise C Stephens, Kim K McLeod, Nikita Chazov, Vadim Krushinsky, Mourad Ghachoui, Boris S Safonov, Cayla M Dedrick, Dennis Conti, Didier Laloum, Steven Giacalone, Carl Ziegler, Pere Guerra Serra, Ramon Naves Nogues, Felipe Murgas, Edward J Michaels, George R Ricker, Roland K Vanderspek, Sara Seager, Joshua N Winn, Jon M Jenkins, Brett Addison, Owen Alfaro, D R Anderson, Elias Aydi, Thomas G Beatty, Timothy R Bedding, Alexander A Belinski, Zouhair Benkhaldoun, Perry Berlind, Cullen H Blake, Michael J Bowen, Brendan P Bowler, Andrew W Boyle, Dalton Branson, César Briceño, Michael L Calkins, Emma Campbell, Jessie L Christiansen, Laura Chomiuk, Kevin I Collins, Matthew A Cornachione, Ahmed Daassou, Courtney D Dressing, Gilbert A Esquerdo, Dax L Feliz, William Fong, Akihiko Fukui, Tianjun Gan, Holden Gill, Maria V Goliguzova, Jarrod Hansen, Thomas Henning, Eric G Hintz, Melissa J Hobson, Jonathan Horner, Chelsea X Huang, David J James, Jacob S Jensen, Samson A Johnson, Andrés Jordán, Stephen R Kane, Khalid Barkaoui, Myung-Jin Kim, Kingsley Kim, Rudolf B Kuhn, Nicholas Law, Pablo Lewin, Hui-Gen Liu, Michael B Lund, Andrew W Mann, Nate McCrady, Matthew W Mengel, Jessica Mink, Lauren G Murphy, Norio Narita, Patrick Newman, Jack Okumura, Hugh P Osborn, Martin Paegert, Enric Palle, Joshua Pepper, Peter Plavchan, Alexander A Popov, Markus Rabus, Jessica Ranshaw, Jennifer A Rodriguez, Dong-Goo Roh, Michael A Reefe, Arjun B Savel, Richard P Schwarz, Avi Shporer, Robert J Siverd, David H Sliski, Keivan G Stassun, Daniel J Stevens, Abderahmane Soubkiou, Eric B Ting, C G Tinney, Noah Vowell, Payton Walton, R G West, Maurice L Wilson, Robert A Wittenmyer, Justin M Wittrock, Shania Wolf, Jason T Wright, Hui Zhang, and Evan Zobel

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the discovery and characterization of six short-period, transiting giant planets from NASA's Transiting Exoplanet Survey Satellite (TESS) -- TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642), TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467). All six planets orbit bright host stars (8.9, Comment: 20 Pages, 6 Figures, 8 Tables, Accepted by MNRAS

Published
2023

23. TESS Delivers Five New Hot Giant Planets Orbiting Bright Stars from the Full-frame Images

Author

Joseph E. Rodriguez, Samuel N. Quinn, George Zhou, Andrew Vanderburg, Louise D. Nielsen, Robert A. Wittenmyer, Rafael Brahm, Phillip A. Reed, Chelsea X. Huang6, Sydney Vach, David R. Ciardi, Ryan J. Oelkers, Keivan G. Stassun, Coel Hellier, B. Scott Gaudi, Jason D. Eastman, Karen A. Collins, Allyson Bieryla, Sam Christian, David W. Latham, Ilaria Carleo, Duncan J. Wright, Elisabeth Matthews, Erica J. Gonzales, Carl Ziegler, Courtney D. Dressing, Steve B. Howell, Thiam-Guan Tan, Justin Wittrock, Peter Plavchan, Kim K. McLeod, David Baker, Gavin Wang, Don J. Radford, Richard P. Schwarz, Massimiliano Esposito, George R. Ricker, Roland K. Vanderspek, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Brett Addison, D. R. Anderson, Thomas Barclay, Thomas G. Beatty, Perry Berlind, Francois Bouchy, Michael Bowen, Brendan P. Bowler, C. E. Brasseur, César Briceño, Douglas A. Caldwell, Michael L. Calkins, Scott Cartwright, Priyanka Chaturvedi, Guillaume Chaverot, Sudhish Chimaladinne, Jessie L. Christiansen, Kevin I. Collins, Ian J. M. Crossfield, Kevin Eastridge, Néstor Espinoza, Gilbert A. Esquerdo, Dax L. Feliz, Tyler Fenske, William Fong, Tianjun Gan, Steven Giacalone, Holden Gill, Lindsey Gordon, A. Granados, Nolan Grieves, Eike W. Guenther, Natalia Guerrero, Thomas Henning, Christopher E. Henze, Katharine Hesse, Melissa J. Hobson, Jonathan Horner, David J. James, Eric L. N. Jensen, Mary Jimenez, Andres Jordan, Stephen R. Kane, John Kielkopf, Kingsley Kim, Rudolf B. Kuhn, Natasha Latouf2, Nicholas M. Law, Alan M. Levine, Michael B. Lund, Andrew W. Mann, Shude Mao, Rachel A. Matson, Matthew W. Mengel, Jessica Mink, Patrick Newman2, Tanner O Dwyer, Jack Okumura, Enric Palle, Joshua Pepper, Elisa V. Quintana, Paula Sarkis, Arjun B. Savel, Joshua E. Schlieder, Chloe Schnaible, Avi Shporer, Ramotholo Sefako, Julia V. Seidel, Robert J. Siverd, Brett Skinner, Manu Stalport, Daniel J. Stevens, Caitlin Stibbards, C. G. Tinney, R. G. West, Daniel A. Yahalomi, and Hui Zhang

Subjects
Astronomy
Abstract

We present the discovery and characterization of five hot and warm Jupiters—TOI-628 b(TIC 281408474; HD288842), TOI-640 b(TIC 147977348), TOI-1333 b (TIC 395171208, BD+47 3521A), TOI-1478 b (TIC409794137), and TOI-1601 b (TIC 139375960)—based on data from NASA’s Transiting Exoplanet Survey Satellite(TESS). The five planets were identified from the full-frame images and were confirmed through a series of photometric and spectroscopic follow-up observations by the TESS Follow-up Observing Program Working Group. The planets are all Jovian size (RP=1.01–1.77RJ) and have masses that range from 0.85 to 6.33MJ. The host stars of these systems have F and G spectral types (5595Teff 6460 K)and are all relatively bright (9.51.7RJ, possibly a result of its host star’s evolution) and resides on an orbit with a period longer than 5 days. TOI-628 b is the most massive, hot Jupiter discovered to date by TESS with a measured mass of-+6.310.300.28MJ and a statistically significant, nonzero orbital eccentricity of e=-+0.0740.0220.021. This planet would not have had enough time to circularize through tidal forces from our analysis, suggesting that it might be remnant eccentricity from its migration. The longest-period planet in this sample, TOI-1478 b (P=10.18 days), is a warm Jupiter in a circular orbit around a near-solar analog. NASA’s TESS mission is continuing to increase the sample of well-characterized hot and warm Jupiters, complementing its primary mission goals.

Published
2021
Full Text
View/download PDF

24. TOI-257b (HD 19916b): a warm sub-saturn orbiting an evolved F-type star

Author

Brett C. Addison, Duncan J. Wright, Belinda A. Nicholson, Bryson Cale, Teo Mocnik, Daniel Huber, Peter Plavchan, Robert A. Wittenmyer, Andrew Vanderburg, William J. Chaplin, Ashley Chontos, Jake T. Clark, Jason D. Eastman, Carl Ziegler, Rafael Brahm, Bradley D. Carter, Mathieu Clerte, Nestor Espinoza, Jonathan Horner, John Bentley, Andres Jordan, Stephen R. Kane, John F. Kielkopf, Emilie Laychock, Matthew W. Mengel, Jack Okumura, Keivan G. Stassun, Timothy R. Bedding, Brendan P. Bowler, Andrius Burnelis, Sergi Blanco-Cuaresma, Michaela Collins, Ian Crossfield, Allen B. Davis, Dag Evensberget, Alexis Heitzmann, Steve B. Howell, Nicholas Law, Andrew W. Mann, Stephen C. Marsden, Rachel A. Matson, James H. O’Connor, Avi Shporer, Catherine Stevens, C. G. Tinney, Christopher Tylor, Songhu Wang, Hui Zhang, Thomas Henning, Diana Kossakowski, George Ricker, Paula Sarkis, Martin Schlecker, Pascal Torres, Roland Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Ismael Mireles, Pam Rowden, Joshua Pepper, Tansu Daylan, Joshua E. Schlieder, Karen A. Collins, Kevin I. Collins, Thiam-Guan Tan, Warrick H. Ball, Sarbani Basu, Derek L. Buzasi, Tiago L. Campante, Enrico Corsaro, L. Gonz´alez-Cuesta, Guy R. Davies, Leandro de Almeida, Jose-Dias do Nascimento Jr, Rafael A. Garcpıa, Zhao Guo, Rasmus Handberg, Saskia Hekker, Daniel R. Hey, Thomas Kallinger, Steven D. Kawaler, Cenk Kayhan, James S. Kuszlewicz, Mikkel N. Lund, Alexander Lyttle, Savita Mathur, Andrea Miglio, Benoit Mosser, Martin B. Nielsen, Aldo M. Serenelli, Victor Silva Aguirre, and Nathalie Themeßl

Subjects
Astrophysics
Abstract

We report the discovery of a warm sub-Saturn, TOI-257b (HD 19916b), based on data from NASA’s Transiting Exoplanet Survey Satellite (TESS). The transit signal was detected by TESS and confirmed to be of planetary origin based on radial velocity observations. An analysis of the TESS photometry, the MINERVA-Australis, FEROS, and HARPS radial velocities, and the asteroseismic data of the stellar oscillations reveals that TOI-257b has a mass of M(P) = 0.138 ± 0.023 M(J) (43.9 ± 7.3 Mꚛ), a radius of R(P) = 0.639 ± 0.013 R(J) (7.16 ± 0.15 Rꚛ⁠), bulk density of 0.65 (+0.12,−0.11) (cgs), and period 18.38818 (+0.00085,−0.00084) days⁠. TOI-257b orbits a bright (V = 7.612 mag) somewhat evolved late F-type star with M⁎ = 1.390 ± 0.046 M(sun)⁠, R⁎ = 1.888 ± 0.033 R(sun)⁠, T(eff) = 6075 ± 90 K⁠, and 𝜈sin 𝑖 = 11.3 ± 0.5 km/s. Additionally, we find hints for a second non-transiting sub-Saturn mass planet on a ∼71 day orbit using the radial velocity data. This system joins the ranks of a small number of exoplanet host stars (∼100) that have been characterized with asteroseismology. Warm sub-Saturns are rare in the known sample of exoplanets, and thus the discovery of TOI-257b is important in the context of future work studying the formation and migration history of similar planetary systems.

Published
2020
Full Text
View/download PDF

25. TOI 564 b and TOI 905 b: Grazing and Fully Transiting Hot Jupiters Discovered by TESS

Author

Allen B. Davis, Songhu Wang, Matias Jones, Jason D. Eastman, Maximilian N. Günther, Keivan G. Stassun, Brett C. Addison, Karen A. Collins, Samuel N. Quinn, David W. Latham, Trifon Trifonov, Sahar Shahaf, Tsevi Mazeh, Stephen R. Kane, Norio Narita, Xian-Yu Wang, Thiam-Guan Tan, David R Ciardi, Andrei Tokovinin, Carl Ziegler, René Tronsgaard, Sarah Millholland, Bryndis Cruz, Perry Berlind, Michael L. Calkins, Gilbert A. Esquerdo, Kevin I. Collins, Dennis M. Conti, Felipe Murgas, Phil Evans, Pablo Lewin, Don J. Radford, Leonardo A. Paredes, Todd J. Henry, James Hodari-Sadiki, Michael B. Lund20, Jessie L. Christiansen20, Nicholas M. Law, Andrew W. Mann, César Briceño, Hannu Parviainen, Enric Pallé, Noriharu Watanabe, George R Ricker, Roland Vanderspek, Sara Seager, Joshua N. Winn, Jon M Jenkins, Akshata Krishnamurthy, Natalie M. Batalha, Jennifer Burt, Knicole Colon, Scott Dynes, Douglas A Caldwell, Robert Morris, Christopher E. Henze, and Debra A Fischer

Subjects
Astronomy
Abstract

We report the discovery and confirmation of two new hot Jupiters discovered by the Transiting Exoplanet Survey Satellite(TESS): TOI 564 b and TOI 905 b. The transits of these two planets were initially observed by TESS with orbital periods of 1.651 and 3.739 days, respectively. We conducted follow-up observations of each system from the ground, including photometry in multiple filters, speckle interferometry, and radial velocity measurements. For TOI 564 b, our global fitting revealed a classical hot Jupiter with a mass of-+1.4630.0960.10MJand a radius of-+1.020.290.71RJ. Also a classical hot Jupiter, TOI 905 b has a mass of-+0.6670.0410.042MJand radius of-+1.1710.0510.053RJ. Both planets orbit Sun-like, moderately bright, mid-G dwarf stars with V11. While TOI 905 b fully transits its star, we found that TOI 564 b has a very high transit impact parameter of-+0.9940.0490.083, making it one of only∼20 known systems to exhibit a grazing transit and one of the brightest host stars among them. Therefore, TOI 564 b is one of the most attractive systems to search for additional nontransiting, smaller planets by exploiting the sensitivity of grazing transits to small changes in inclination and transit duration over a timescale of several years.

Published
2020
Full Text
View/download PDF

26. TOI-824 b: A New Planet on the Lower Edge of the Hot Neptune Desert

Author

Jennifer A. Burt, Louise D. Nielsen, Samuel N. Quinn, Eric E. Mamajek, Elisabeth C. Matthews, George Zhou, Julia V. Seidel, Chelsea X. Huang, Eric Lopez, Maritza Soto, Jon Otegi, Keivan G. Stassun, Laura Kreidberg, Karen A. Collins, Jason D. Eastman, Joseph E. Rodriguez, Andrew Vanderburg, Samuel P. Halverson, Johanna K. Teske, Sharon X. Wang, R. Paul Butler, François Bouchy, Xavier Dumusque, Damien Segransen, Stephen A. Shectman, Jeffrey D. Crane, Fabo Feng, Benjamin T. Montet, Adina D. Feinstein, Yuri Beletski, Erin Flowers, Maximilian N. Günther, Tansu Daylan, Kevin I. Collins, Dennis M. Conti, Tianjun Gan, Eric L. N. Jensen, John F. Kielkopf, Thiam-Guan Tan, Ravit Helled, Caroline Dorn, Jonas Haldemann, Jack J. Lissauer, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Joseph D. Twicken, Jeffrey C. Smith, Peter Tenenbaum, Scott Cartwright, Thomas Barclay, Joshua Pepper, Gilbert Esquerdo, and William Fong

Subjects
Astronomy, Astrophysics
Abstract

We report the detection of a transiting hot Neptune exoplanet orbiting TOI-824 (SCR J1448-5735), a nearby (d = 64 pc) K4V star, using data from the Transiting Exoplanet Survey Satellite. The newly discovered planet has a radius Rp = 2.93 ± 0.20 Rꚛ and an orbital period of 1.393 days. Radial velocity measurements using the Planet Finder Spectrograph and the High Accuracy Radial velocity Planet Searcher spectrograph confirm the existence of the planet, and we estimate its mass to be 18.47 ± 1.84 Mꚛ. The planet's mean density is ρ(p)= 4.03 (+0.98,-0.78)g/cu. cm, making it more than twice as dense as Neptune. TOI-824 b's high equilibrium temperature makes the planet likely to have a cloud-free atmosphere, and thus it is an excellent candidate for follow-up atmospheric studies. The detectability of TOI-824 b's atmosphere from both ground and space is promising and could lead to the detailed characterization of the most irradiated small planet at the edge of the hot Neptune desert that has retained its atmosphere to date.

Published
2020
Full Text
View/download PDF

27. KELT-25 b and KELT-26 b: A Hot Jupiter and a Substellar Companion Transiting Young A Stars Observed by TESS

Author

Romy Rodríguez Martínez, B. Scott Gaudi, Joseph E. Rodriguez, George Zhou, Jonathan Labadie-Bartz, Samuel N. Quinn, Kaloyan Penev, Thiam-Guan Tan, David W. Latham, Leonardo A. Paredes, John F. Kielkopf, Brett C. Addison, Duncan J. Wright, Johanna Teske, Steve B Howell, David R Ciardi, Carl Ziegler, Keivan G. Stassun, Marshall C. Johnson, Jason D. Eastman, Robert J. Siverd, Thomas G. Beatty, Luke Bouma, Timothy Bedding, Joshua Pepper, Joshua N. Winn, Michael B. Lund, Steven Villanueva Jr, Daniel J. Stevens, Eric L. N. Jensen, Coleman Kilby, Jeffrey D. Crane, Andrei Tokovinin, Mark E. Everett, Chris G. Tinney, Michael Martin Fausnaugh, David H Cohen, Daniel Bayliss, Allyson Bieryla, Phillip A. Cargile, Karen A. Collins, Dennis M. Conti, Knicole Colon, Ivan A. Curtis, D. L. Depoy, Phil Evans, Dax L. Feliz, Joao Gregorio, Jason Rothenberg, David J. James, Michael D. Joner, Rudolf B. Kuhn, Mark Manner, Somayeh Khakpash, Jennifer L. Marshall, Kim K. McLeod, Matthew T. Penny, Phillip A. Reed, Howard M. Relles, Denise C. Stephens, Chris Stockdale, Mark Trueblood, Pat Trueblood, Xinyu Yao, Roberto Zambelli, Roland Vanderspek, Sara Seager, Jon M Jenkins, Todd J. Henry, Hodari-Sadiki James, Wei-Chun Jao, Sharon Xuesong Wang, Aaron Paul Butler, Ian Thompson, Stephen Shectman, Robert A. Wittenmyer, Brendan P. Bowler, Jonathan Horner, Stephen R. Kane, Matthew W. Mengel, Timothy D. Morton, Jack Okumura, Peter Plavchan, Hui Zhang, Nicholas Joseph Scott, Rachel A. Matson, Andrew W. Mann, Diana Dragomir, Max Günther, Eric B Ting, Ana Glidden, and Elisa Victoria Quintana

Subjects
Astronomy
Abstract

We present the discoveries of KELT-25 b (TIC 65412605, TOI-626.01) and KELT-26 b (TIC 160708862, TOI-1337.01), two transiting companions orbiting relatively bright, early A stars. The transit signals were initially detected by the KELT survey and subsequently confirmed by Transiting Exoplanet Survey Satellite (TESS) photometry. KELT-25 b is on a 4.40 day orbit around the V=9.66 star CD-24 5016(=-+T8280eff180440K,Må=-+2.180.110.12Me), while KELT-26 b is on a 3.34 day orbit around the V=9.95 star HD 134004 (Teff=-+8640240500K,Må=-+1.930.160.14Me), which is likely an Am star. We have confirmed the substellar nature of both companions through detailed characterization of each system using ground-based and TESS photometry, radial velocity measurements, Doppler tomography, and high-resolution imaging. For KELT-25, we determine a companion radius of RP=-+1.640.0430.039RJ and a 3σupper limit on the companion’s mass of64MJ. For KELT-26 b, we infer a planetary mass and radius of MP=-+1.410.510.43MJ and RP=-+1.940.0580.060RJ. From Doppler tomographic observations, we find KELT-26 b to reside in a highly misaligned orbit. This conclusion is weakly corroborated by a subtle asymmetry in the transit light curve from the TESS data. KELT-25 b appears to be in a well-aligned, prograde orbit, and the system is likely a member of the cluster Theia 449.

Published
2020
Full Text
View/download PDF

28. The First Habitable-zone Earth-sized Planet from TESS. II. Spitzer Confirms TOI-700 d

Author

Joseph E. Rodriguez, Andrew Vanderburg, Sebastian Zieba, Laura Kreidberg, Caroline V. Morley, Jason D. Eastman, Stephen R. Kane, Alton Spencer, Samuel N. Quinn, Ryan Cloutier, Chelsea X. Huang, Karen A. Collins, Andrew W. Mann, Emily Gilbert, Joshua E. Schlieder, Elisa V. Quintana, Thomas Barclay, Gabrielle Suissa, Ravi kumar Kopparapu, Courtney D. Dressing, George R. Ricker, Roland K. Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Zachory Berta-Thompson, Patricia T. Boyd, David Charbonneau, Douglas A. Caldwell, Eugene Chiang, Jessie L. Christiansen, David R. Ciardi, Knicole D. Colón, John Doty, Tianjun Gan, Natalia Guerrero, Maximilian N. Günther, Eve J. Lee, Alan M. Levine, Eric Lopez, Philip S. Muirhead, Elisabeth Newton, Mark E. Rose, Joseph D. Twicken, and Jesus Noel Villaseñor

Subjects
Astronomy, Astrophysics
Abstract

We present Spitzer 4.5 μm observations of the transit of TOI-700 d, a habitable-zone Earth-sized planet in a multiplanet system transiting a nearby M-dwarf star (TIC 150428135, 2MASS J06282325–6534456). TOI-700 d has a radius of 1.144 (+0.062, -0.061)Rꚛ and orbits within its host star’s conservative habitable zone with a period of 37.42 days (T(eq)~269 K). TOI-700 also hosts two small inner planets (R(b)=1.037(+0.065, -0.064) Rꚛ and R(c)=2.65(+0.16,-0.15) Rꚛ with periods of 9.98 and 16.05 days, respectively. Our Spitzer observations confirm the Transiting Exoplanet Survey Satellite (TESS) detection of TOI-700 d and remove any remaining doubt that it is a genuine planet. We analyze the Spitzer light curve combined with the 11 sectors of TESS observations and a transit of TOI-700 c from the LCOGT network to determine the full system parameters. Although studying the atmosphere of TOI-700 d is not likely feasible with upcoming facilities, it may be possible to measure the mass of TOI-700 d using state-of-the-art radial velocity (RV) instruments (expected RV semiamplitude of ∼70 cm/s).

Published
2020
Full Text
View/download PDF

29. TOI-677b: A Warm Jupiter (P=11.2 days) on an Eccentric Orbit Transiting a Late F-type Star

Author

Andrés Jordán, Rafael Brahm, Néstor Espinoza, Thomas Henning, Matías I. Jones, Diana Kossakowski, Paula Sarkis, Trifon Trifonov, Felipe Rojas, Pascal Torres, Holger Drass, Sangeetha Nandakumar, Mauro Barbieri, Allen Davis, Songhu Wang, Daniel Bayliss, Luke Bouma, Diana Dragomir, Jason D. Eastman, Tansu Daylan, Natalia Guerrero, Thomas Barclay, Eric B Ting, Christopher E. Henze, George Ricker, Roland Vanderspek, David W. Latham, Sara Seager, Joshua Winn, Jon M Jenkins, Robert A. Wittenmyer, Brendan P. Bowler, Ian Crossfield, Jonathan Horner, Stephen R. Kane, John F. Kielkopf, Timothy D. Morton, Peter Plavchan, C. G. Tinney, Brett Addison, Matthew W. Mengel, Jack Okumura, Sahar Shahaf, Tsevi Mazeh, Markus Rabus, Avi Shporer, Carl Ziegler, Andrew W. Mann, and Rhodes Hart

Subjects
Astronomy
Abstract

We report the discovery of TOI-677b,first identified as a candidate in light curves obtained within Sectors 9 and 10 of the Transiting Exoplanet Survey Satellite(TESS)mission and confirmed with radial velocities. TOI-677b has a mass of M(p) = 1.236(+0.069,- 0.067) M(J), a radius of R(P)=1.170 ± 0.03 R(J), and orbits its bright host star (V = 9.8 mag) with an orbital period of 11.23660 ± 0.00011 d, on an eccentric orbit with e = 0.435 ± 0.024. The host star has a mass of M(*) = 1.181 ± 0.058 M(ʘ), a radius of R(*)= 1.28(+0.03,-0.03) R(ʘ), an age of 2.92 (+0.80,-0.73) Gyr and solar metallicity, properties consistent with a main-sequence late-F star with T(eff)=6295 ± 77K. We find evidence in the radial velocity measurements of a secondary long-term signal, which could be due to an outer companion. The TOI-677 b system is a well-suited target for Rossiter–Mclaughlin observations that can constrain migration mechanisms of close-in giant planets.

Published
2020
Full Text
View/download PDF

30. The Magellan-TESS Survey. I. Survey Description and Midsurvey Results* †

Author

Johanna Teske, Sharon Xuesong Wang, Angie Wolfgang, Tianjun Gan, Mykhaylo Plotnykov, David J. Armstrong, R. Paul Butler, Bryson Cale, Jeffrey D. Crane, Ward Howard, Eric L. N. Jensen, Nicholas Law, Stephen A. Shectman, Peter Plavchan, Diana Valencia, Andrew Vanderburg, George R. Ricker, Roland Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Vardan Adibekyan, David Barrado, Susana C. C. Barros, Zouhair Benkhaldoun, David J. A. Brown, Edward M. Bryant, Jennifer Burt, Douglas A. Caldwell, David Charbonneau, Ryan Cloutier, Karen A. Collins, Kevin I. Collins, Knicole D. Colon, Dennis M. Conti, Olivier D. S. Demangeon, Jason D. Eastman, Mohammed Elmufti, Fabo Feng, Erin Flowers, Natalia M. Guerrero, Saeed Hojjatpanah, Jonathan M. Irwin, Giovanni Isopi, Jorge Lillo-Box, Franco Mallia, Bob Massey, Mayuko Mori, Susan E. Mullally, Norio Narita, Taku Nishiumi, Ares Osborn, Martin Paegert, Jerome Pitogo de Leon, Samuel N. Quinn, Michael Reefe, Richard P. Schwarz, Avi Shporer, Abderahmane Soubkiou, Sérgio G. Sousa, Chris Stockdale, Paul A. Strøm, Thiam-Guan Tan, Jiaxin Tang, Peter Tenenbaum, Peter J. Wheatley, Justin Wittrock, Daniel A. Yahalomi, and Farzaneh Zohrabi

Published
2021
Full Text
View/download PDF

31. The K2 & TESS Synergy II: Revisiting 26 systems in the TESS Primary Mission

Author

Erica Thygesen, Jessica A. Ranshaw, Joseph E. Rodriguez, Andrew Vanderburg, Samuel N. Quinn, Jason D. Eastman, Allyson Bieryla, David W. Latham, Roland K. Vanderspek, Jon M. Jenkins, Douglas A. Caldwell, Mma Ikwut-Ukwa, Knicole D. Colón, Jessie Dotson, Christina Hedges, Karen A. Collins, Michael L. Calkins, Perry Berlind, and Gilbert A. Esquerdo

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

The legacy of NASA's K2 mission has provided hundreds of transiting exoplanets that can be revisited by new and future facilities for further characterization, with a particular focus on studying the atmospheres of these systems. However, the majority of K2-discovered exoplanets have typical uncertainties on future times of transit within the next decade of greater than four hours, making observations less practical for many upcoming facilities. Fortunately, NASA's Transiting exoplanet Survey Satellite (TESS) mission is reobserving most of the sky, providing the opportunity to update the ephemerides for $\sim$300 K2 systems. In the second paper of this series, we reanalyze 26 single-planet, K2-discovered systems that were observed in the TESS primary mission by globally fitting their K2 and TESS lightcurves (including extended mission data where available), along with any archival radial velocity measurements. As a result of the faintness of the K2 sample, 13 systems studied here do not have transits detectable by TESS. In those cases, we re-fit the K2 lightcurve and provide updated system parameters. For the 23 systems with $M_* \gtrsim 0.6 M_\odot$, we determine the host star parameters using a combination of Gaia parallaxes, Spectral Energy Distribution (SED) fits, and MESA Isochrones and Stellar Tracks (MIST) stellar evolution models. Given the expectation of future TESS extended missions, efforts like the K2 & TESS Synergy project will ensure the accessibility of transiting planets for future characterization while leading to a self-consistent catalog of stellar and planetary parameters for future population efforts., Accepted for publication in ApJ. 29 pages, 9 figures, 12 tables

Published
2023

32. Seeing-limited Coupling of Starlight into Single-mode Fiber with a Small Telescope

Author

David H. Sliski, Cullen H. Blake, Jason D. Eastman, and Samuel Halverson

Subjects
Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract

An optical fiber link to a telescope provides many advantages for spectrometers designed to detect and characterize extrasolar planets through precise radial velocity (PRV) measurements. In the seeing-limited regime, a multi-mode fiber is typically used so that a significant amount of starlight may be captured. In the near-diffraction-limited case, either with an adaptive optics system or with a small telescope at an excellent site, efficiently coupling starlight into a much smaller, single-mode fiber may be possible. In general, a spectrometer designed for single-mode fiber input will be substantially less costly than one designed for multi-mode fiber input. We describe the results of tests coupling starlight from a 70 cm telescope at Mt. Hopkins, Arizona into the single-mode fiber of the MINERVA-Red spectrometer at a wavelength of ~850 nm using a low-speed tip/tilt image stabilization system comprising all commercial, off-the-shelf components. We find that approximately 0.5% of the available starlight is coupled into the single-mode fiber under seeing conditions typical for observatories hosting small telescopes, which is close to the theoretical expectation. We discuss scientific opportunities for small telescopes paired with inexpensive, high-resolution spectrometers, as well as upgrade paths that should significantly increase the coupling efficiency for the MINERVA-Red system., Comment: 8 pages, 4 figures. Accepted for publication in Astronomische Nachrichten

Published
2023
Full Text
View/download PDF

33. KELT-24b: A 5M(J) Planet on a 5.6 day Well-aligned Orbit around the Young V=8.3 F-star HD 93148

Author

Joseph E. Rodriguez, Jason D. Eastman, George Zhou, Samuel N. Quinn, Thomas G. Beatty, Kaloyan Penev, Marshall C. Johnson, Phillip A. Cargile, David W. Latham, Allyson Bieryla, Karen A. Collins, Courtney Dressing, David R Ciardi, Howard M. Relles, Gabriel Murawski, Taku Nishiumi, Atsunori Yonehara, Ryo Ishimaru, Fumi Yoshida, Joao Gregorio, Michael B. Lund, Daniel J. Stevens, Keivan G. Stassun, B. Scott Gaudi, Knicole Colon, Joshua Pepper, Norio Narita, Supachai Awiphan, Pongpichit Chuanraksasat, Paul Benni, Roberto Zambelli, Lehman H. Garrison, Maurice L. Wilson, Matthew A. Cornachione, Sharon X. Wang, Jonathan Labadie-Bartz, Romy Rodríguez, Robert J. Siverd, Xinyu Yao, Daniel Bayliss, Perry Berlind, Michael L. Calkins, Jessie L. Christiansen, David H Cohen, Dennis M. Conti, Ivan A. Curtis, D. L. Depoy, Gilbert A. Esquerdo, Phil Evans35, Dax Feliz, Benjamin J Fulton, Thomas W.-S. Holoien, David J. James, Tharindu Jayasinghe, Hannah Jang-condell, Eric L. N. Jensen, John A. Johnson, Michael D. Joner, Somayeh Khakpash, John F. Kielkopf, Rudolf B. Kuhn, Mark Manner, Jennifer L. Marshall, Kim K. McLeod, Nate McCrady, Thomas E. Oberst, Ryan J. Oelkers, Matthew T. Penny, Phillip A. Reed, David H. Sliski, B. J. Shappee, Denise C. Stephens, Chris Stockdale, Thiam-Guan Tan, Mark Trueblood, Pat Trueblood, Steven Villanueva Jr, Robert A. Wittenmyer, and Jason T. Wright

Subjects
Astronomy
Abstract

We present the discovery of KELT-24 b, a massive hot Jupiter orbiting a bright (V=8.3 mag, K=7.2 mag) young F-star with a period of 5.6 days. The host star, KELT-24 (HD 93148), has a Teff=-+65094950K, a mass of M*=+1.4600.0590.055Me, a radius of R*=1.506±0.022Re, and an age of +0.780.420.61Gyr. Its planetary companion (KELT-24 b) has a radius of RP=1.272±0.021RJ and a mass of MP=-+5.180.220.21MJ, and from Doppler tomographic observations, we find that the planet’s orbit is well aligned to its host star’s projected spin axis (l=-+2.63.65.1). The young age estimated for KELT-24 suggests that it only recently started to evolve from the zero-age main sequence. KELT-24 is the brightest star known to host a transiting giant planet with a period between 5 and 10 days. Although the circularization timescale is much longer than the age of the system, we do not detect a large eccentricity or significant misalignment that is expected from dynamical migration. The brightness of its host star and its moderate surface gravity make KELT-24b an intriguing target for detailed atmospheric characterization through spectroscopic emission measurements since it would bridge the current literature results that have primarily focused on lower mass hot Jupiters and a few brown dwarfs.

Published
2019
Full Text
View/download PDF

34. Three Red Suns in the Sky: A Transiting, Terrestrial Planet in a Triple M-dwarf System at 6.9 pc

Author

Jennifer G. Winters, Amber A. Medina, Jonathan M. Irwin, David Charbonneau, Nicola Astudillo-Defru, Elliott P. Horch, Jason D. Eastman, Eliot Halley Vrijmoet, Todd J. Henry, Hannah Diamond-Lowe, Elaine Winston, Thomas Barclay, Xavier Bonfils, George R Ricker, Roland Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M Jenkins, Stéphane Udry, Joseph D Twicken, Johanna K. Teske, Peter Gregory Tenenbaum, Francesco Pepe, Felipe Murgas, Philip S. Muirhead, Jessica Mink, Christophe Lovis, Alan M. Levine, Sébastien Lépine, Wei-Chun Jao, Christopher E. Henze, Gábor Furész, Thierry Forveille, Pedro Figueira, Gilbert A. Esquerdo, Courtney D. Dressing, Rodrigo F. Díaz, Xavier Delfosse, Christopher J Burke, François Bouchy, Perry Berlind, and Jose-Manuel Almenara

Subjects
Astronomy
Abstract

We present the discovery from Transiting Exoplanet Survey Satellite (TESS) data of LTT 1445Ab. At a distance of 6.9 pc, it is the second nearest transiting exoplanet system found to date, and the closest one known for which the primary is an M dwarf. The host stellar system consists of three mid-to-late M dwarfs in a hierarchical configuration, which are blended in one TESS pixel. We use MEarth data and results from the Science Processing Operations Center data validation report to determine that the planet transits the primary star in the system. The planet has a radius of {1.38}_{-0.12}^{+0.13} {R}_{\oplus }, an orbital period of {5.35882}_{-0.00031}^{+0.00030} days, and an equilibrium temperature of {433}_{-27}^{+28} K. With radial velocities from the High Accuracy Radial Velocity Planet Searcher, we place a 3σ upper mass limit of 8.4 {M}_{\oplus } on the planet. LTT 1445Ab provides one of the best opportunities to date for the spectroscopic study of the atmosphere of a terrestrial world. We also present a detailed characterization of the host stellar system. We use high-resolution spectroscopy and imaging to rule out the presence of any other close stellar or brown dwarf companions. Nineteen years of photometric monitoring of A and BC indicate a moderate amount of variability, in agreement with that observed in the TESS light-curve data. We derive a preliminary astrometric orbit for the BC pair that reveals an edge-on and eccentric configuration. The presence of a transiting planet in this system hints that the entire system may be co-planar, implying that the system may have formed from the early fragmentation of an individual protostellar core.

Published
2019
Full Text
View/download PDF

35. KELT-23Ab: A Hot Jupiter Transiting a Near-solar Twin Close to the TESS and JWST Continuous Viewing Zones

Author

Daniel Johns, Phillip A. Reed, Joseph E. Rodriguez, Joshua Pepper, Keivan G. Stassun, Kaloyan Penev, B. Scott Gaudi, Jonathan Labadie-Bartz, Benjamin J Fulton, Samuel N. Quinn, Jason D. Eastman, David R Ciardi, Lea Hirsch, Daniel J. Stevens, Catherine P. Stevens, Thomas E. Oberst, David H Cohen, Eric L. N. Jensen, Paul Benni, Steven Villanueva Jr, Gabriel Murawski, Allyson Bieryla, David W. Latham, Siegfried Vanaverbeke, Franky Dubois, Steve Rau, Ludwig Logie, Ryan F. Rauenzahn, Robert A. Wittenmyer, Roberto Zambelli, Daniel Bayliss, Thomas G. Beatty, Karen A. Collins, Knicole Colon, Ivan A. Curtis, Phil Evans, Joao Gregorio, David James, D. L. Depoy, Marshall C. Johnson, Michael D. Joner, David H. Kasper, Somayeh Khakpash, John F. Kielkopf, Rudolf B. Kuhn, Michael B. Lund, Mark Manner, Jennifer L. Marshall, Kim K. McLeod, Matthew T. Penny, Howard Relles, Robert J. Siverd, Denise C. Stephens, Chris Stockdale, Thiam-Guan Tan, Mark Trueblood, Pat Trueblood, and Xinyu Yao

Subjects
Astronomy
Abstract

We announce the discovery of KELT-23Ab, a hot Jupiter transiting the relatively bright(V = 10.3) star BD+66911(TYC 4187-996-1), and characterize the system using follow-up photometry and spectroscopy. A global fit to the system yields host-star properties of= T5900 49effK,=-+MM0.9450.0540.060*, = RR0.995 0.015*, =-+LL1.0820.0480.051*, =-+ glog 4.4180.0250.026 (cgs), and=- Fe H0.105 0.077. KELT-23Ab is a hot Jupiter with a mass of= -+ MM0.938P0.0420.045J, radius of = RR1.322 0.025PJ, and density of r=-+ 0.504P0.0350.038gcm − 3. Intense insolation flux from the star has likely caused KELT-23Ab to become inflated. The time of inferior conjunction is=T2458149.40776=0.00091 BJD0TDB and the orbital period is=-+P2.2553530.0000300.000031days. There is strong evidence that KELT-23A is a member of a long-period binary star system with a less luminous companion, and due to tidal interactions, the planet is likely to spiral into its host within roughly a gig a year. This system has one of the highest positive ecliptic latitudes of all transiting planet hosts known to date, placing it near the Transiting Planet Survey Satellite and James Webb Space Telescope continuous viewing zones. Thus we expect it to be an excellent candidate for long-term monitoring and follow up with these facilities.

Published
2019
Full Text
View/download PDF

36. An Eccentric Massive Jupiter Orbiting a Subgiant on a 9.5-day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame Images

Author

Joseph E. Rodriguez, Samuel N. Quinn, Chelsea X. Huang, Andrew Vanderburg, Kaloyan Penev, Rafael Brahm, Andres Jordan, Mma Ikwut Ukwa, Shelly Tsirulik, David W. Latham, Keivan G. Stassun, Avi Shporer, Carl Ziegler, Elisabeth Matthews, Jason D. Eastman, B. Scott Gaudi, Karen A. Collins, Natalia Guerrero, Howard M. Relles, Thomas Barclay, Natalie M. Batalha, Perry Berlind, Allyson Bieryla, L. G. Bouma, Patricia T Boyd, Jennifer Burt, Michael L. Calkins, Jessie Christiansen, David R. Ciardi, Knicole D Colon, Dennis M. Conti, Ian J. M. Crossfield, Tansu Daylan, Jason Dittmann, Diana Dragomir, Scott Dynes, Nestor Espinoza, Gilbert A. Esquerdo, Zahra Essack, Aylin Garcia Soto, Ana Glidden, Maximilian N. Gunther, Thomas Henning, Jon M Jenkins, John F. Kielkopf, Akshata Krishnamurthy, Nicholas M. Law, Alan M. Levine, Pablo Lewin, Andrew W. Mann, Edward H. Morgan, Robert L Morris, Ryan J. Oelkers, Martin Paegert, Joshua Pepper, Elisa V Quintana, George R. Ricker, Pamela Rowden, Sara Seager, Paula Sarkis, Joshua E Schlieder, Lizhou Sha, Andrei Tokovinin, Guillermo Torres, Roland K. Vanderspek, Steven Villanueva Jr, Jesus Noel Villasenor, Joshua N. Winn, Bill Wohler, Ian Wong, Daniel A. Yahalomi, Liang Yu, Zhuchang Zhan, and George Zhou

Subjects
Astronomy
Abstract

We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only the TESS full frame images, because the host star was not chosen as a two-minute cadence target. From a global analysis of the TESS photometry and follow-up observations carried out by the TESS Follow-up Observing Program Working Group, TOI-172 (TIC 29857954) is a slightly evolved star with an effective temperature of T(eff) = 5645 ± 50 K, a mass of M(⋆) =1.128(sub -0.061, sup +0.065) M(☉), radius of R(⋆) =1.777(sub -0.044, sup +0.047) R(☉), a surface gravity of log g(⋆) =3.993(sub -0.028, sup +0.027), and an age of 7.4(sub -1.5, sup +1.6) Gyr. Its planetary companion (TOI-172 b) has a radius of R(P) =0.965(sub -0.029, sup +0.032) R(J), a mass of M(P) =5.42(sub -0.20, sup +0.22) M(J), and is on an eccentric orbit (e=0.3806(sub -0.0090, sup +0.0093)). TOI-172 b is one of the few known massive giant planets on a highly eccentric short-period orbit. Future study of the atmosphere of this planet and its system architecture offer opportunities to understand the formation and evolution of similar systems.

Published
2019
Full Text
View/download PDF

37. KELT-22Ab: A Massive, Short-Period Hot Jupiter Transiting a Near-solar Twin

Author

Knicole Colon, David R Ciardi, Jonathan Labadie-Bartz, Joseph E. Rodriguez, Keivan G. Stassun, Kaloyan Penev, Marshall C. Johnson, B. Scott Gaudi, Knicole D. Colón, Allyson Bieryla, David W. Latham, Joshua Pepper, Karen A. Collins, Phil Evans, Howard Relles, Robert J. Siverd, Joao Bento, Xinyu Yao, Chris Stockdale, Thiam-Guan Tan, George Zhou, Jason D. Eastman, Michael D. Albrow, Daniel Bayliss, Thomas G. Beatty, Perry Berlind, Valerio Bozza, Michael L. Calkins, David H. Cohen, Ivan A. Curtis, Gilbert A. Esquerdo, Dax Feliz, Benjamin J Fulton, Joao Gregorio, David James, Eric L. N. Jensen, John A. Johnson, Samson A. Johnson, Michael D. Joner, David Kasper, John F. Kielkopf, Rudolf B. Kuhn, Michael B. Lund, Amber Malpas, Mark Manner, Nate McCrady, Kim K. McLeod, Thomas E. Oberst, Matthew T. Penny, Phillip A. Reed, David H. Sliski, Denise C. Stephens, Daniel J. Stevens, Jr, Robert A. Wittenmyer, J. T. Wright, and Roberto Zambelli

Subjects
Lunar And Planetary Science And Exploration, Space Sciences (General)
Abstract

We present the discovery of KELT-22Ab, a hot Jupiter from the KELT-South survey. KELT-22Ab transits the moderately bright (V11.1) Sun-like G2V star TYC 7518-468-1. The planet has an orbital period of P = 1.3866529 0.0000027 days, a radius of = -R 1.285+ R P 0.071 J 0.12 , and a relatively large mass of = - M 3.47+ M P 0.14 J 0.15 . The star has = - + R 1.099 0.046 R 0.079 , = - + M 1.092 0.041 M 0.045 , = - T 5767+ eff 49 50 K, = - log g 4.393+0.0600.039 (cgs), and [m/H]=+ -0.259+0.0830.085; thus other than its slightly super-solar metallicity, it appears to be a near-solar twin. Surprisingly, KELT-22A exhibits kinematics and a Galactic orbit that are somewhat atypical for thin-disk stars. Nevertheless, the star is rotating rapidly for its estimated age, and shows evidence of chromospheric activity. Imaging reveals a slightly fainter companion to KELT-22A that is likely bound, with a projected separation of 6″ (∼1400 au). In addition to the orbital motion caused by the transiting planet, we detect a possible linear trend in the radial velocity of KELT-22A, suggesting the presence of another relatively nearby body that is perhaps non-stellar. KELT-22Ab is highly irradiated (as a consequence of the small semimajor axis of a R = 4.97), and is mildly inflated. At such small separations, tidal forces become significant. The configuration of this system is optimal for measuring the rate of tidal dissipation within the host star. Our models predict that, due to tidal forces, the semimajor axis is decreasing rapidly, and KELT-22Ab is predicted to spiral into the star within the next Gyr.

Published
2019
Full Text
View/download PDF

38. The TESS Grand Unified Hot Jupiter Survey. II. Twenty New Giant Planets

Author

Samuel W. Yee, Joshua N. Winn, Joel D. Hartman, Luke G. Bouma, George Zhou, Samuel N. Quinn, David W. Latham, Allyson Bieryla, Joseph E. Rodriguez, Karen A. Collins, Owen Alfaro, Khalid Barkaoui, Corey Beard, Alexander A. Belinski, Zouhair Benkhaldoun, Paul Benni, Krzysztof Bernacki, Andrew W. Boyle, R. Paul Butler, Douglas A. Caldwell, Ashley Chontos, Jessie L. Christiansen, David R. Ciardi, Kevin I. Collins, Dennis M. Conti, Jeffrey D. Crane, Tansu Daylan, Courtney D. Dressing, Jason D. Eastman, Zahra Essack, Phil Evans, Mark E. Everett, Sergio Fajardo-Acosta, Raquel Forés-Toribio, Elise Furlan, Mourad Ghachoui, Michaël Gillon, Coel Hellier, Ian Helm, Andrew W. Howard, Steve B. Howell, Howard Isaacson, Emmanuel Jehin, Jon M. Jenkins, Eric L. N. Jensen, John F. Kielkopf, Didier Laloum, Naunet Leonhardes-Barboza, Pablo Lewin, Sarah E. Logsdon, Jack Lubin, Michael B. Lund, Mason G. MacDougall, Andrew W. Mann, Natalia A. Maslennikova, Bob Massey, Kim K. McLeod, Jose A. Muñoz, Patrick Newman, Valeri Orlov, Peter Plavchan, Adam Popowicz, Francisco J. Pozuelos, Tyler A. Pritchard, Don J. Radford, Michael Reefe, George R. Ricker, Alexander Rudat, Boris S. Safonov, Richard P. Schwarz, Heidi Schweiker, Nicholas J. Scott, S. Seager, Stephen A. Shectman, Chris Stockdale, Thiam-Guan Tan, Johanna K. Teske, Neil B. Thomas, Mathilde Timmermans, Roland Vanderspek, David Vermilion, David Watanabe, Lauren M. Weiss, Richard G. West, Judah Van Zandt, Michal Zejmo, Carl Ziegler, Ministerio de Ciencia e Innovación (España), and John Templeton Foundation

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

Full list of authors: Yee, Samuel W.; Winn, Joshua N.; Hartman, Joel D.; Bouma, Luke G.; Zhou, George; Quinn, Samuel N.; Latham, David W.; Bieryla, Allyson; Rodriguez, Joseph E.; Collins, Karen A.; Alfaro, Owen; Barkaoui, Khalid; Beard, Corey; Belinski, Alexander A.; Benkhaldoun, Zouhair; Benni, Paul; Bernacki, Krzysztof; Boyle, Andrew W.; Butler, R. Paul; Caldwell, Douglas A.; Chontos, Ashley; Christianse, Jessie L.; Cia, David R.; Coll, Kevin I.; Conti, Dennis M.; Crane, Jeffrey D.; Daylan, Tansu; Dressing, Courtney D.; Eastman, Jason D.; Essack, Zahra; Evans, Phil; Everett, Mark E.; Fajardo-Acosta, Sergio; Fores-Toribio, Raquel; Furlan, Elise; Ghachoui, Mourad; Gillon, Michael; Hellier, Coel; Helm, Ian; Howard, Andrew W.; Howell, Steve B.; Isaacson, Howard; Jehin, Emmanuel; Jenkin, Jon M.; Jensen, Eric L. N.; Kielkopf, John F.; Laloum, Didier; Leonhardes-Barboza, Naunet; Lewin, Pablo; Logsdon, Sarah E.; Lubin, Jack; Lund, Michael B.; MacDougall, Mason G.; Mann, Andrew W.; Maslennikova, Natalia A.; Massey, Bob; McLeod, Kim K.; Munoz, Jose A.; Newman, Patrick; Orlov, Valeri; Plavchan, Peter; Popowicz, Adam; Pozuelos, Francisco J.; Pritchard, Tyler A.; Radford, Don J.; Reefe, Michael; Ricker, George R.; Rudat, Alexander; Safonov, Boris S.; Schwarz, Richard P.; Schweiker, Heidi; Scott, Nicholas J.; Seager, S.; Shectman, Stephen A.; Stockdale, Chris; Tan, Thiam-Guan; Teske, Johanna K.; Thomas, Neil B.; Timmermans, Mathilde; Vanderspek, Roland; Vermilion, David; Watanabe, David; Weiss, Lauren M.; West, Richard G.; Van Zandt, Judah; Zejmo, Michal; Ziegler, Carl.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., NASA's Transiting Exoplanet Survey Satellite (TESS) mission promises to improve our understanding of hot Jupiters by providing an all-sky, magnitude-limited sample of transiting hot Jupiters suitable for population studies. Assembling such a sample requires confirming hundreds of planet candidates with additional follow-up observations. Here we present 20 hot Jupiters that were detected using TESS data and confirmed to be planets through photometric, spectroscopic, and imaging observations coordinated by the TESS Follow-up Observing Program. These 20 planets have orbital periods shorter than 7 days and orbit relatively bright FGK stars (10.9 < G < 13.0). Most of the planets are comparable in mass to Jupiter, although there are four planets with masses less than that of Saturn. TOI-3976b, the longest-period planet in our sample (P = 6.6 days), may be on a moderately eccentric orbit (e = 0.18 ± 0.06), while observations of the other targets are consistent with them being on circular orbits. We measured the projected stellar obliquity of TOI-1937A b, a hot Jupiter on a 22.4 hr orbit with the Rossiter–McLaughlin effect, finding the planet's orbit to be well aligned with the stellar spin axis (∣λ∣ = 4fdg0 ± 3fdg5). We also investigated the possibility that TOI-1937 is a member of the NGC 2516 open cluster but ultimately found the evidence for cluster membership to be ambiguous. These objects are part of a larger effort to build a complete sample of hot Jupiters to be used for future demographic and detailed characterization work. © 2023. The Author(s). Published by the American Astronomical Society., J.H. acknowledges funding from NASA grant 80NSSC21K0335. This work was supported by an LSSTC Catalyst Fellowship awarded by LSST Corporation to T.D. with funding from the John Templeton Foundation grant ID No. 62192. K.K.M. acknowledges support from the New York Community Trustâs Fund for Astrophysical Research. N.L.-B. thanks the NASA Massachusetts Space Grant for support. A.A.B., N.A.M., and B.S.S. acknowledge the support of the Ministry of Science and Higher Education of the Russian Federation under the grant 075-15-2020-780 (N13.1902.21.0039). A.P. acknowledges grant BK-246/RAu-11/2022. The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liege (Belgium), in collaboration with Cadi Ayyad University of Marrakech (Morocco)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

Published
2022

39. The TESS Grand Unified Hot Jupiter Survey. I. Ten TESS Planets

Author

Samuel W. Yee, Joshua N. Winn, Joel D. Hartman, Joseph E. Rodriguez, George Zhou, Samuel N. Quinn, David W. Latham, Allyson Bieryla, Karen A. Collins, Brett C. Addison, Isabel Angelo, Khalid Barkaoui, Paul Benni, Andrew W. Boyle, Rafael Brahm, R. Paul Butler, David R. Ciardi, Kevin I. Collins, Dennis M. Conti, Jeffrey D. Crane, Fei Dai, Courtney D. Dressing, Jason D. Eastman, Zahra Essack, Raquel Forés-Toribio, Elise Furlan, Tianjun Gan, Steven Giacalone, Holden Gill, Eric Girardin, Thomas Henning, Christopher E. Henze, Melissa J. Hobson, Jonathan Horner, Andrew W. Howard, Steve B. Howell, Chelsea X. Huang, Howard Isaacson, Jon M. Jenkins, Eric L. N. Jensen, Andrés Jordán, Stephen R. Kane, John F. Kielkopf, Slawomir Lasota, Alan M. Levine, Jack Lubin, Andrew W. Mann, Bob Massey, Kim K. McLeod, Matthew W. Mengel, Jose A. Muñoz, Felipe Murgas, Enric Palle, Peter Plavchan, Adam Popowicz, Don J. Radford, George R. Ricker, Pamela Rowden, Boris S. Safonov, Arjun B. Savel, Richard P. Schwarz, S. Seager, Ramotholo Sefako, Avi Shporer, Gregor Srdoc, Ivan S. Strakhov, Johanna K. Teske, C. G. Tinney, Dakotah Tyler, Robert A. Wittenmyer, Hui Zhang, and Carl Ziegler

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of ten short-period giant planets (TOI-2193A b, TOI-2207 b, TOI-2236 b, TOI-2421 b, TOI-2567 b, TOI-2570 b, TOI-3331 b, TOI-3540A b, TOI-3693 b, TOI-4137 b). All of the planets were identified as planet candidates based on periodic flux dips observed by NASA's Transiting Exoplanet Survey Satellite (TESS). The signals were confirmed to be from transiting planets using ground-based time-series photometry, high angular resolution imaging, and high-resolution spectroscopy coordinated with the TESS Follow-up Observing Program. The ten newly discovered planets orbit relatively bright F and G stars ($G < 12.5$,~$T_\mathrm{eff}$ between 4800 and 6200 K). The planets' orbital periods range from 2 to 10~days, and their masses range from 0.2 to 2.2 Jupiter masses. TOI-2421 b is notable for being a Saturn-mass planet and TOI-2567 b for being a ``sub-Saturn'', with masses of $0.322\pm 0.073$ and $0.195\pm 0.030$ Jupiter masses, respectively. In most cases, we have little information about the orbital eccentricities. Two exceptions are TOI-2207 b, which has an 8-day period and a detectably eccentric orbit ($e = 0.17\pm0.05$), and TOI-3693 b, a 9-day planet for which we can set an upper limit of $e < 0.052$. The ten planets described here are the first new planets resulting from an effort to use TESS data to unify and expand on the work of previous ground-based transit surveys in order to create a large and statistically useful sample of hot Jupiters., 44 pages, 15 tables, 21 figures; revised version submitted to AJ

Published
2022

40. A Second Planet Transiting LTT 1445A and a Determination of the Masses of Both Worlds

Author

Jennifer G. Winters, Ryan Cloutier, Amber A. Medina, Jonathan M. Irwin, David Charbonneau, Nicola Astudillo-Defru, Xavier Bonfils, Andrew W. Howard, Howard Isaacson, Jacob L. Bean, Andreas Seifahrt, Johanna K. Teske, Jason D. Eastman, Joseph D. Twicken, Karen A. Collins, Eric L. N. Jensen, Samuel N. Quinn, Matthew J. Payne, Martti H. Kristiansen, Alton Spencer, Andrew Vanderburg, Mathias Zechmeister, Lauren M. Weiss, Sharon Xuesong Wang, Gavin Wang, Stéphane Udry, Ivan A. Terentev, Julian Stürmer, Gudmundur Stefánsson, Avi Shporer, Stephen Shectman, Ramotholo Sefako, Hans Martin Schwengeler, Richard P. Schwarz, Nicholas Scarsdale, Ryan A. Rubenzahl, Arpita Roy, Lee J. Rosenthal, Paul Robertson, Erik A. Petigura, Francesco Pepe, Mark Omohundro, Joseph M. Akana Murphy, Felipe Murgas, Teo Močnik, Benjamin T. Montet, Ronald Mennickent, Andrew W. Mayo, Bob Massey, Jack Lubin, Christophe Lovis, Pablo Lewin, David Kasper, Stephen R. Kane, Jon M. Jenkins, Daniel Huber, Keith Horne, Michelle L. Hill, Paula Gorrini, Steven Giacalone, Benjamin Fulton, Thierry Forveille, Pedro Figueira, Tara Fetherolf, Courtney Dressing, Rodrigo F. Díaz, Xavier Delfosse, Paul A. Dalba, Fei Dai, C. C. Cortés, Ian J. M. Crossfield, Jeffrey D. Crane, Dennis M. Conti, Kevin I. Collins, Ashley Chontos, R. Paul Butler, Peyton Brown, Madison Brady, Aida Behmard, Corey Beard, Natalie M. Batalha, Jose-Manuel Almenara, Université du Québec à Rimouski (UQAR), Departamento de Matemática y Fı́sica Aplicadas [Concepcion] (DMFA), Universidad Católica de la Santísima Concepción (UCSC), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
STELLAR ACTIVITY, FOS: Physical sciences, SUPER-EARTH, Astrophysics::Cosmology and Extragalactic Astrophysics, EARTH-SIZED PLANET, HARPS, NEARBY, QB Astronomy, Astrophysics::Solar and Stellar Astrophysics, QC, TERRESTRIAL PLANET, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, QB, MCC, Earth and Planetary Astrophysics (astro-ph.EP), RADIAL-VELOCITIES, ERROR-CORRECTION, M DWARFS, Astronomy and Astrophysics, 3rd-DAS, QC Physics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], SYSTEM, Astrophysics - Earth and Planetary Astrophysics
Abstract

LTT 1445 is a hierarchical triple M-dwarf star system located at a distance of 6.86 parsecs. The primary star LTT 1445A (0.257 M_Sun) is known to host the transiting planet LTT 1445Ab with an orbital period of 5.4 days, making it the second closest known transiting exoplanet system, and the closest one for which the host is an M dwarf. Using TESS data, we present the discovery of a second planet in the LTT 1445 system, with an orbital period of 3.1 days. We combine radial velocity measurements obtained from the five spectrographs ESPRESSO, HARPS, HIRES, MAROON-X, and PFS to establish that the new world also orbits LTT 1445A. We determine the mass and radius of LTT 1445Ab to be 2.87+/-0.25 M_Earth and 1.304^{+0.067}_{-0.060} R_Earth, consistent with an Earth-like composition. For the newly discovered LTT 1445Ac, we measure a mass of 1.54^{+0.20}_{-0.19} M_Earth and a minimum radius of 1.15 R_Earth, but we cannot determine the radius directly as the signal-to-noise of our light curve permits both grazing and non-grazing configurations. Using MEarth photometry and ground-based spectroscopy, we establish that star C (0.161 M_Sun) is likely the source of the 1.4-day rotation period, and star B (0.215 M_Sun) has a likely rotation period of 6.7 days. We estimate a probable rotation period of 85 days for LTT 1445A. Thus, this triple M-dwarf system appears to be in a special evolutionary stage where the most massive M dwarf has spun down, the intermediate mass M dwarf is in the process of spinning down, while the least massive stellar component has not yet begun to spin down., Comment: Accepted to the Astronomical Journal. 4 tables, 10 figures; RV table available upon request

Published
2022

41. The <scp>HD</scp> 217107 planetary system: Twenty years of radial velocity measurements

Author

Stephen R. Kane, Cullen H. Blake, Robert A. Wittenmyer, Samson A. Johnson, David H. Sliski, Jason T. Wright, Audrey Houghton, Maurice Wilson, Mark R. Giovinazzi, Jonathan Horner, Nate McCrady, Joseph P. Glaser, John Asher Johnson, Peter Plavchan, Jason D. Eastman, and Juliana Garcia-Mejia

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010308 nuclear & particles physics, FOS: Physical sciences, Astronomy and Astrophysics, Orbital eccentricity, Astrophysics, Planetary system, 01 natural sciences, Exoplanet, Radial velocity, Orbit, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Hot Jupiter, Precession, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

The hot Jupiter HD 217107 b was one of the first exoplanets detected using the radial velocity (RV) method, originally reported in the literature in 1999. Today, precise RV measurements of this system span more than 20 years, and there is clear evidence for a longer-period companion, HD 217107 c. Interestingly, both the short-period planet ($P_\mathrm{b}\sim7.13$ d) and long-period planet ($P_\mathrm{c}\sim5059$ d) have significantly eccentric orbits ($e_\mathrm{b}\sim0.13$ and $e_\mathrm{c}\sim0.40$). We present 42 additional RV measurements of this system obtained with the MINERVA telescope array and carry out a joint analysis with previously published RV measurements from four different facilities. We confirm and refine the previously reported orbit of the long-period companion. HD 217107 b is one of a relatively small number of hot Jupiters with an eccentric orbit, opening up the possibility of detecting precession of the planetary orbit due to General Relativistic effects and perturbations from other planets in the system. In this case, the argument of periastron, $\omega$, is predicted to change at the level of $\sim$0.8$^\circ$ century$^{-1}$. Despite the long time baseline of our observations and the high quality of the RV measurements, we are only able to constrain the precession to be $\dot{\omega}, Comment: 8 pages, 3 figures, accepted for publication in Astronomische Nachrichten

Published
2020

42. Transit Timing Variations for AU Microscopii b & c

Author

Justin M. Wittrock, Stefan Dreizler, Michael A. Reefe, Brett M. Morris, Peter P. Plavchan, Patrick J. Lowrance, Brice-Olivier Demory, James G. Ingalls, Emily A. Gilbert, Thomas Barclay, Bryson L. Cale, Karen A. Collins, Kevin I. Collins, Ian J. M. Crossfield, Diana Dragomir, Jason D. Eastman, Mohammed El Mufti, Dax Feliz, Jonathan Gagné, Eric Gaidos, Peter Gao, Claire S. Geneser, Leslie Hebb, Christopher E. Henze, Keith D. Horne, Jon M. Jenkins, Eric L. N. Jensen, Stephen R. Kane, Laurel Kaye, Eder Martioli, Teresa A. Monsue, Enric Pallé, Elisa V. Quintana, Don J. Radford, Veronica Roccatagliata, Joshua E. Schlieder, Richard P. Schwarz, Avi Shporer, Keivan G. Stassun, Christopher Stockdale, Thiam-Guan Tan, Angelle M. Tanner, Andrew Vanderburg, Laura D. Vega, Songhu Wang, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science

Subjects
530 Physics, 520 Astronomy, astro-ph.EP, Astronomy and Astrophysics, 610 Medicine & health, 3rd-DAS, QC Physics, Space and Planetary Science, 570 Life sciences, biology, QB Astronomy, QC, QB, Astrophysics - Earth and Planetary Astrophysics
Abstract

We explore the transit timing variations (TTVs) of the young (22 Myr) nearby AU Mic planetary system. For AU Mic b, we introduce three Spitzer (4.5 $\mu$m) transits, five TESS transits, 11 LCO transits, one PEST transit, one Brierfield transit, and two transit timing measurements from Rossiter-McLaughlin observations; for AU Mic c, we introduce three TESS transits. We present two independent TTV analyses. First, we use EXOFASTv2 to jointly model the Spitzer and ground-based transits and to obtain the midpoint transit times. We then construct an O--C diagram and model the TTVs with Exo-Striker. Second, we reproduce our results with an independent photodynamical analysis. We recover a TTV mass for AU Mic c of 10.8$^{+2.3}_{-2.2}$ M$_{E}$. We compare the TTV-derived constraints to a recent radial-velocity (RV) mass determination. We also observe excess TTVs that do not appear to be consistent with the dynamical interactions of b and c alone, and do not appear to be due to spots or flares. Thus, we present a hypothetical non-transiting "middle-d" candidate exoplanet that is consistent with the observed TTVs, the candidate RV signal, and would establish the AU Mic system as a compact resonant multi-planet chain in a 4:6:9 period commensurability. These results demonstrate that the AU Mic planetary system is dynamically interacting producing detectable TTVs, and the implied orbital dynamics may inform the formation mechanisms for this young system. We recommend future RV and TTV observations of AU Mic b and c to further constrain the masses and to confirm the existence of possible additional planet(s)., Comment: Corrected typos; revised Section 3, 4, and 5 to reflect reanalysis, results unchanged. Submitted to AAS Journals Nov 11th, 2020; favorable referee report received Jan 3rd; final draft accepted for publication in the AJ Apr 19th

Published
2022

43. K2-79b and K2-222b: Mass Measurements of Two Small Exoplanets with Periods beyond 10 days that Overlap with Periodic Magnetic Activity Signals

Author

Chantanelle Nava, Mercedes López-Morales, Annelies Mortier, Li Zeng, Helen A. C. Giles, Allyson Bieryla, Andrew Vanderburg, Lars A. Buchhave, Ennio Poretti, Steven H. Saar, Xavier Dumusque, David W. Latham, David Charbonneau, Mario Damasso, Aldo S. Bonomo, Christophe Lovis, Andrew Collier Cameron, Jason D. Eastman, Alessandro Sozzetti, Rosario Cosentino, Marco Pedani, Francesco Pepe, Emilio Molinari, Dimitar Sasselov, Michel Mayor, Manu Stalport, Luca Malavolta, Ken Rice, Christopher A. Watson, A. F. Martinez Fiorenzano, Luca Di Fabrizio, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, Nava, Chantanelle [0000-0001-8838-3883], López-Morales, Mercedes [0000-0003-3204-8183], Mortier, Annelies [0000-0001-7254-4363], Zeng, Li [0000-0003-1957-6635], Giles, Helen AC [0000-0001-6777-4797], Bieryla, Allyson [0000-0001-6637-5401], Vanderburg, Andrew [0000-0001-7246-5438], Buchhave, Lars A [0000-0003-1605-5666], Poretti, Ennio [0000-0003-1200-0473], Saar, Steven H [0000-0001-7032-8480], Dumusque, Xavier [0000-0002-9332-2011], Latham, David W [0000-0001-9911-7388], Charbonneau, David [0000-0002-9003-484X], Damasso, Mario [0000-0001-9984-4278], Bonomo, Aldo S [0000-0002-6177-198X], Eastman, Jason D [0000-0003-3773-5142], Sozzetti, Alessandro [0000-0002-7504-365X], Pedani, Marco [0000-0002-5752-6260], Molinari, Emilio [0000-0002-1742-7735], Sasselov, Dimitar [0000-0001-7014-1771], Mayor, Michel [0000-0002-9352-5935], Malavolta, Luca [0000-0002-6492-2085], Martinez Fiorenzano, AF [0000-0002-4272-4272], Apollo - University of Cambridge Repository, Nava, C [0000-0001-8838-3883], López-Morales, M [0000-0003-3204-8183], Mortier, A [0000-0001-7254-4363], Zeng, L [0000-0003-1957-6635], Giles, HAC [0000-0001-6777-4797], Bieryla, A [0000-0001-6637-5401], Vanderburg, A [0000-0001-7246-5438], Buchhave, LA [0000-0003-1605-5666], Poretti, E [0000-0003-1200-0473], Saar, SH [0000-0001-7032-8480], Dumusque, X [0000-0002-9332-2011], Latham, DW [0000-0001-9911-7388], Charbonneau, D [0000-0002-9003-484X], Damasso, M [0000-0001-9984-4278], Bonomo, AS [0000-0002-6177-198X], Eastman, JD [0000-0003-3773-5142], Sozzetti, A [0000-0002-7504-365X], Pedani, M [0000-0002-5752-6260], Molinari, E [0000-0002-1742-7735], Sasselov, D [0000-0001-7014-1771], Mayor, M [0000-0002-9352-5935], and Malavolta, L [0000-0002-6492-2085]

Subjects
MCC, Earth and Planetary Astrophysics (astro-ph.EP), The Solar System, Exoplanets, and Astrobiology, Exoplanet astronomy, FOS: Physical sciences, Astronomy and Astrophysics, 3rd-DAS, Stellar activity, QC Physics, Space and Planetary Science, astro-ph.EP, QB Astronomy, QC, Astrophysics - Earth and Planetary Astrophysics, QB
Abstract

We present mass and radius measurements of K2-79b and K2-222b, two transiting exoplanets orbiting active G-type stars. Their respective 10.99d and 15.39d orbital periods fall near periods of signals induced by stellar magnetic activity. The two signals might therefore interfere and lead to an inaccurate estimate of exoplanet mass. We present a method to mitigate these effects when radial velocity and activity indicator observations are available over multiple observing seasons and the orbital period of the exoplanet is known. We perform correlation and periodogram analyses on sub-sets composed of each target's two observing seasons, in addition to the full data sets. For both targets, these analyses reveal an optimal season with little to no interference at the orbital period of the known exoplanet. We make a confident mass detection of each exoplanet by confirming agreement between fits to the full radial velocity set and the optimal season. For K2-79b, we measure a mass of 11.8 $\pm$ 3.6 $M_{Earth}$ and a radius of 4.09 $\pm$ 0.17 $R_{Earth}$. For K2-222b, we measure a mass of 8.0 $\pm$ 1.8 $M_{Earth}$ and a radius of 2.35 $\pm$ 0.08 $R_{Earth}$. According to model predictions, K2-79b is a highly irradiated Uranus-analog and K2-222b hosts significant amounts of water ice. We also present an RV solution for a candidate second companion orbiting K2-222 at 147.5d., Comment: 33 pages, 17 figures, 13 tables

Published
2022
Full Text
View/download PDF

44. The TESS-Keck Survey. VIII. Confirmation of a Transiting Giant Planet on an Eccentric 261 day Orbit with the Automated Planet Finder Telescope

Author

Paul A. Dalba, Stephen R. Kane, Diana Dragomir, Steven Villanueva, Karen A. Collins, Thomas Lee Jacobs, Daryll M. LaCourse, Robert Gagliano, Martti H. Kristiansen, Mark Omohundro, Hans M. Schwengeler, Ivan A. Terentev, Andrew Vanderburg, Benjamin Fulton, Howard Isaacson, Judah Van Zandt, Andrew W. Howard, Daniel P. Thorngren, Steve B. Howell, Natalie M. Batalha, Ashley Chontos, Ian J. M. Crossfield, Courtney D. Dressing, Daniel Huber, Erik A. Petigura, Paul Robertson, Arpita Roy, Lauren M. Weiss, Aida Behmard, Corey Beard, Casey L. Brinkman, Steven Giacalone, Michelle L. Hill, Jack Lubin, Andrew W. Mayo, Teo Močnik, Joseph M. Akana Murphy, Alex S. Polanski, Malena Rice, Lee J. Rosenthal, Ryan A. Rubenzahl, Nicholas Scarsdale, Emma V. Turtelboom, Dakotah Tyler, Paul Benni, Pat Boyce, Thomas M. Esposito, E. Girardin, Didier Laloum, Pablo Lewin, Christopher R. Mann, Franck Marchis, Richard P. Schwarz, Gregor Srdoc, Jana Steuer, Thirupathi Sivarani, Athira Unni, Nora L. Eisner, Tara Fetherolf, Zhexing Li, Xinyu Yao, Joshua Pepper, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Christopher J. Burke, Jason D. Eastman, Michael B. Lund, David R. Rodriguez, Pamela Rowden, Eric B. Ting, and Jesus Noel Villaseñor

Subjects
JUPITER, Earth and Planetary Astrophysics (astro-ph.EP), Radial velocity, Science & Technology, RADIAL-VELOCITY, ERROR-CORRECTION, Extrasolar gaseous giant planets, FOS: Physical sciences, Astronomy and Astrophysics, Astronomy & Astrophysics, MASS, I, HUNTERS TESS, SIZED PLANET, Amateur astronomy, Space and Planetary Science, STELLAR COMPANIONS, Physical Sciences, Astrophysics::Earth and Planetary Astrophysics, Transit photometry, Planetary interior, EXTRASOLAR PLANETS, SINGLE TRANSIT, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of TOI-2180 b, a 2.8 $M_{\rm J}$ giant planet orbiting a slightly evolved G5 host star. This planet transited only once in Cycle 2 of the primary Transiting Exoplanet Survey Satellite (TESS) mission. Citizen scientists identified the 24 hr single-transit event shortly after the data were released, allowing a Doppler monitoring campaign with the Automated Planet Finder telescope at Lick Observatory to begin promptly. The radial velocity observations refined the orbital period of TOI-2180 b to be 260.8$\pm$0.6 days, revealed an orbital eccentricity of 0.368$\pm$0.007, and discovered long-term acceleration from a more distant massive companion. We conducted ground-based photometry from 14 sites spread around the globe in an attempt to detect another transit. Although we did not make a clear transit detection, the nondetections improved the precision of the orbital period. We predict that TESS will likely detect another transit of TOI-2180 b in Sector 48 of its extended mission. We use giant planet structure models to retrieve the bulk heavy-element content of TOI-2180 b. When considered alongside other giant planets with orbital periods over 100 days, we find tentative evidence that the correlation between planet mass and metal enrichment relative to stellar is dependent on orbital properties. Single-transit discoveries like TOI-2180 b highlight the exciting potential of the TESS mission to find planets with long orbital periods and low irradiation fluxes despite the selection biases associated with the transit method., Comment: Published in AJ

Published
2022
Full Text
View/download PDF

45. HD 207897 b:A dense sub-Neptune transiting a nearby and bright K-type star

Author

Andrew W. Mayo, Jorge Lillo-Box, George R. Ricker, C. Moutou, Stephen R. Kane, René Tronsgaard, Ashley Chontos, Allyson Bieryla, Karen A. Collins, Nicola Astudillo-Defru, Luc Arnold, Rafael Luque, Andrew W. Howard, Xavier Dumusque, S. G. Sousa, V. Bourrier, Erik Petigura, Joshua N. Winn, Magali Deleuil, Lauren M. Weiss, Enric Palle, Nuno C. Santos, Steven Giacalone, J. Rey, Damien Ségransan, Courtney D. Dressing, Paul A. Dalba, Arpita Roy, Jack Lubin, Sara Seager, Corey Beard, Natalie M. Batalha, Daniel Huber, C. E. Brasseur, T. Lopez, Howard Isaacson, Teo Mocnik, Jason D. Eastman, Peter Tenenbaum, N. Heidari, Michelle L. Hill, P. Cortés-Zuleta, O. Mousis, E. Delgado Mena, Diana Dragomir, D. W. Latham, François Bouchy, Aida Behmard, David Ehrenreich, P. A. Strøm, Fei Dai, F. Vakili, T. Forveille, Tansu Daylan, R. Vanderspek, Keivan G. Stassun, Alexandre Santerne, Melissa J. Hobson, X. Bonfils, Benjamin J. Fulton, G. Montagnier, M. Stalport, Francesco Pepe, Lars A. Buchhave, Flavien Kiefer, Nicholas Scarsdale, Lee J. Rosenthal, Vardan Adibekyan, Paul Robertson, Olivier Demangeon, J. M. Jenkins, A. Carmona, Nematollah Riazi, Stéphane Udry, Rodrigo F. Díaz, N. C. Hara, G. Gaisne, Thomas Barclay, Tara Fetherolf, X. Delfosse, L. Mignon, Sergio Hoyer, B. Courcol, J. Orell-Mique, S. Borgniet, Guillaume Hébrard, Ryan A. Rubenzahl, Lea A. Hirsch, S. Dalal, Ian J. M. Crossfield, Joseph M. Akana Murphy, L. Acuna, Isabelle Boisse, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Geneva Observatory, Université de Genève = University of Geneva (UNIGE), European Southern Observatory (ESO), Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), Departamento de Matemática y Fı́sica Aplicadas [Concepcion] (DMFA), Universidad Católica de la Santísima Concepción (UCSC), University of St Andrews [Scotland], Faculdade de Ciências [Lisboa], Universidade de Lisboa = University of Lisbon (ULISBOA), SwRI Planetary Science Directorate [Boulder], Southwest Research Institute [Boulder] (SwRI), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, NASA Ames Research Center Cooperative for Research in Earth Science in Technology (ARC-CREST), NASA Ames Research Center (ARC), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Observatoire Astronomique de l'Université de Genève (ObsGE), National Space Institute [Lyngby] (DTU Space), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), SETI Institute, Instituto de Astrofísica e Ciências do Espaço (IASTRO), MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology (MIT), Department of Astronomy, University of California, Genome Sequencing Center, University of Washington School of Medicine, Universidad de Chile = University of Chile [Santiago] (UCHILE), Departamento de Quimica Inorganica e Ingenieria Quimica (Cordoba, Spain), Universidad de Córdoba = University of Córdoba [Córdoba], Peoples Friendship University of Russia [RUDN University] (RUDN), Center for Astrophysics (emeritus), Harvard-Smithsonian, Cambridge, MA, USA, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire de Didactique André Revuz (LDAR (EA_4434)), Université d'Artois (UA)-Université Paris Diderot - Paris 7 (UPD7)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Instituto de Astrofisica de Canarias (IAC), Universidad de La Laguna [Tenerife - SP] (ULL), Vanderbilt University [Nashville], SLAC National Accelerator Laboratory (SLAC), Stanford University, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Peyton Hall, Clarient Pathology Services, Partenaires INRAE, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), University of Geneva [Switzerland], Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Centro de Astrofísica da Universidade do Porto (CAUP), Universidade do Porto = University of Porto, Instituto de Astronomía y Física del Espacio [Buenos Aires] (IAFE), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Universidad de Buenos Aires [Buenos Aires] (UBA), IFP Energies nouvelles (IFPEN), Center for Space Research [Cambridge] (CSR), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and ANR-18-CE31-0019,SPlaSH,Recherche de planètes habitables avec SPIRou(2018)

Subjects
Physics, Earth and Planetary Astrophysics (astro-ph.EP), education.field_of_study, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 010308 nuclear & particles physics, Population, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Radius, Planetary system, Star (graph theory), 01 natural sciences, Exoplanet, Radial velocity, 13. Climate action, Space and Planetary Science, Planet, Neptune, 0103 physical sciences, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], education, 010303 astronomy & astrophysics, QB, Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the discovery and characterization of a transiting sub-Neptune orbiting with a 16.20 day period around a nearby (28 pc) and bright(V=8.37) K0V star HD207897 (TOI-1611). This discovery is based on photometric measurements from the Transiting Exoplanet Survey Satellite(TESS) mission and radial velocity (RV) observations from the SOPHIE, Automated Planet Finder (APF) and HIRES high precision spectrographs. We used EXOFASTv2 for simultaneously modeling the parameters of the planet and its host star, combining photometric and RV data to determine the planetary system parameters. We show that the planet has a radius of 2.50+/-0.08 RE and a mass of either 14.4+/-1.6 ME or 15.9+/-1.6 ME with nearly equal probability; the two solutions correspond to two possibilities for the stellar activity period. Hence, the density is either 5.1+/-0.7 g cm^-3 or 5.5^{+0.8}_{-0.7} g cm^-3, making it one of the relatively rare dense sub-Neptunes. The existence of such a dense planet at only 0.12 AU from its host star is unusual in the currently observed sub-Neptune (2, Comment: 18 pages, 12 figures, 6 tables; accepted for publication in the A&A journal; comments welcome

Published
2022

47. First Radial Velocity Results From the MINiature Exoplanet Radial Velocity Array (MINERVA)

Author

Maurice L. Wilson, Jason D. Eastman, Matthew A. Cornachione, Sharon X. Wang, Samson A. Johnson, David H. Sliski, William J. Schap III, Timothy D. Morton, John Asher Johnson, Nate McCrady, Jason T. Wright, Robert A. Wittenmyer, Peter Plavchan, Cullen H. Blake, Jonathan J. Swift, Michael Bottom, Ashley D. Baker, Stuart I. Barnes, Perry Berlind, Eric Blackhurst, Thomas G. Beatty, Adam S. Bolton, Bryson Cale, Michael L. Calkins, Ana Colón, Jon de Vera, Gilbert Esquerdo, Emilio E. Falco, Pascal Fortin, Juliana Garcia-Mejia, Claire Geneser, Steven R. Gibson, Gabriel Grell, Ted Groner, Samuel Halverson, John Hamlin, M. Henderson, J. Horner, Audrey Houghton, Stefaan Janssens, Graeme Jonas, Damien Jones, Annie Kirby, George Lawrence, Julien Andrew Luebbers, Philip S. Muirhead, Justin Myles, Chantanelle Nava, Kevin O Rivera-García, Tony Reed, Howard M. Relles, Reed Riddle, Connor Robinson, Forest Chaput de Saintonge, and Anthony Sergi

Published
2019
Full Text
View/download PDF

48. TOI-674b: An oasis in the desert of exo-Neptunes transiting a nearby M dwarf

Author

Xavier Bonfils, Michael W. Werner, Nicola Astudillo-Defru, Jon M. Jenkins, George R. Ricker, Ian J. M. Crossfield, Eric L. N. Jensen, David R. Ciardi, Emmanuel Jehin, Judith Korth, David W. Latham, Farisa Y. Morales, Ismael Mireles, Keivan G. Stassun, Étienne Artigau, Rodrigo F. Díaz, J. Orell-Miquel, Pedro Figueira, Stéphane Udry, René Doyon, X. Delfosse, Jack J. Lissauer, Francesco Pepe, Damien Ségransan, Nuno C. Santos, Christophe Lovis, Peter Tenenbaum, Elisa V. Quintana, Björn Benneke, Rachel A. Matson, Jose-Manuel Almenara, Felipe Murgas, Douglas A. Caldwell, Kevin I. Collins, Phil Evans, C. E. Brasseur, Stephen R. Kane, François Bouchy, David Charbonneau, G. Morello, Roland Vanderspek, Charles Beichman, Elisabeth Matthews, T. Forveille, Khalid Barkaoui, Sara Seager, Diana Dragomir, Erica J. Gonzales, Robert F. Goeke, G. Gaisne, Joshua E. Schlieder, John H. Livingston, Natalia Guerrero, Claudio Melo, Alan M. Levine, Joshua N. Winn, Steve B. Howell, Michaël Gillon, Francisco J. Pozuelos, Jason D. Eastman, Varoujan Gorjian, Karen A. Collins, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Departamento de Matemática y Fı́sica Aplicadas [Concepcion] (DMFA), Universidad Católica de la Santísima Concepción (UCSC), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), and Children's Hospital of Leeds

Subjects
010504 meteorology & atmospheric sciences, GASEOUS PLANETS [PLANETS AND SATELLITES], FOS: Physical sciences, RADIAL VELOCITIES [TECHNIQUES], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, purl.org/becyt/ford/1 [https], Planet, 0103 physical sciences, GENERAL [PLANETS AND SATELLITES], PLANETARY SYSTEMS, 010303 astronomy & astrophysics, INDIVIDUAL: TOI-674 [STARS], Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Orbital elements, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Radius, purl.org/becyt/ford/1.3 [https], PHOTOMETRIC [TECHNIQUES], Light curve, Orbital period, Exoplanet, Radial velocity, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Planetary mass, Astrophysics - Earth and Planetary Astrophysics
Abstract

We use TESS, Spitzer, ground-based light curves and HARPS spectrograph radial velocity measurements to establish the physical properties of the transiting exoplanet candidate TOI-674b. We perform a joint fit of the light curves and radial velocity time series to measure the mass, radius, and orbital parameters of the candidate. We confirm and characterize TOI-674b, a low-density super-Neptune transiting a nearby M dwarf. The host star (TIC 158588995, $V = 14.2$ mag, $J = 10.3$ mag) is characterized by its M2V spectral type with $\mathrm{M}_\star=0.420\pm 0.010$ M$_\odot$, $\mathrm{R}_\star = 0.420\pm 0.013$ R$_\odot$, and $\mathrm{T}_{\mathrm{eff}} = 3514\pm 57$ K, and is located at a distance $d=46.16 \pm 0.03$ pc. Combining the available transit light curves plus radial velocity measurements and jointly fitting a circular orbit model, we find an orbital period of $1.977143 \pm 3\times 10^{-6}$ days, a planetary radius of $5.25 \pm 0.17$ $\mathrm{R}_\oplus$, and a mass of $23.6 \pm 3.3$ $\mathrm{M}_\oplus$ implying a mean density of $\rho_\mathrm{p} = 0.91 \pm 0.15$ [g cm$^{-3}$]. A non-circular orbit model fit delivers similar planetary mass and radius values within the uncertainties. Given the measured planetary radius and mass, TOI-674b is one of the largest and most massive super-Neptune class planets discovered around an M type star to date. It is also a resident of the so-called Neptunian desert and a promising candidate for atmospheric characterisation using the James Webb Space Telescope., Comment: 22 pages, 16 figures. Accepted for publication in A&A

Published
2021

49. The K2-3 System Revisited: Testing Photoevaporation and Core-powered Mass Loss with Three Small Planets Spanning the Radius Valley

Author

Hannah Diamond-Lowe, Laura Kreidberg, C. E. Harman, Eliza M.-R. Kempton, Leslie A. Rogers, Simon R. G. Joyce, Jason D. Eastman, George W. King, Ravi Kopparapu, Allison Youngblood, Molly R. Kosiarek, John H. Livingston, Kevin K. Hardegree-Ullman, and Ian J. M. Crossfield

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Ultraviolet astronomy, Exoplanet evolution, FOS: Physical sciences, Astronomy and Astrophysics, M dwarf stars, X-ray astronomy, Astrophysics - Solar and Stellar Astrophysics, Exoplanet atmospheric composition, Space and Planetary Science, Hubble Space Telescope, Low mass stars, Exoplanet systems, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

Multi-planet systems orbiting M dwarfs provide valuable tests of theories of small planet formation and evolution. K2-3 is an early M dwarf hosting three small exoplanets (1.5-2.0 Earth radii) at distances of 0.07-0.20 AU. We measure the high-energy spectrum of K2-3 with HST/COS and XMM-Newton, and use empirically-driven estimates of Ly-alpha and extreme ultraviolet flux. We use EXOFASTv2 to jointly fit radial velocity, transit, and SED data. This constrains the K2-3 planet radii to 4% uncertainty and the masses of K2-3b and c to 13% and 30%, respectively; K2-3d is not detected in RV measurements. K2-3b and c are consistent with rocky cores surrounded by solar composition envelopes (mass fractions of 0.36% and 0.07%), H2O envelopes (55% and 16%), or a mixture of both. However, based on the high-energy output and estimated age of K2-3, it is unlikely that K2-3b and c retain solar composition atmospheres. We pass the planet parameters and high-energy stellar spectrum to atmospheric models. Dialing the high-energy spectrum up and down by a factor of 10 produces significant changes in trace molecule abundances, but not at a level detectable with transmission spectroscopy. Though the K2-3 planets span the small planet radius valley, the observed system architecture cannot be readily explained by photoevaporation or core-powered mass loss. We instead propose 1) the K2-3 planets are all volatile-rich, with K2-3d having a lower density than typical of super-Earths, and/or 2) the K2-3 planet architecture results from more stochastic processes such as planet formation, planet migration, and impact erosion., 15 pages, 7 figure, published in AJ, HLSPs at https://archive.stsci.edu/hlsp/mstarpanspec

Published
2022

50. TOI-1231 b: A Temperate, Neptune-Sized Planet Transiting the Nearby M3 Dwarf NLTT 24399

Author

Wenceslas Marie-Sainte, Xavier Bonfils, Ian J. M. Crossfield, Christopher J. Burke, François-Xavier Schmider, Fabo Feng, Stephen A. Shectman, Antonio García Muñoz, Tansu Daylan, Elisabeth Matthews, Keivan G. Stassun, Diana Dragomir, Zachory K. Berta-Thompson, Abdelkrim Agabi, Rachel A. Matson, Nicolas Crouzet, Bill Wohler, Roland Vanderspek, Jennifer Burt, Johanna Teske, Sara Seager, C. E. Brasseur, David Charbonneau, Djamel Mékarnia, George R. Ricker, Amaury H. M. J. Triaud, Chelsea X. Huang, John McCann, Joshua Pepper, Jason D. Eastman, Allison Youngblood, Jeffrey D. Crane, Eric E. Mamajek, Lyu Abe, Karen A. Collins, Carl Ziegler, Tristan Guillot, Laura Kreidberg, Paul Mollière, David R. Ciardi, Daniel J. Stevens, Marion Cointepas, David W. Latham, Richard P. Schwarz, Andrew W. Mann, Joshua E. Schlieder, Joshua N. Winn, Georgina Dransfield, Elise Furlan, Eric L. N. Jensen, Steven Villanueva, Joseph E. Rodriguez, Jon M. Jenkins, Steve B. Howell, Sharon X. Wang, Arvind F. Gupta, Nicholas M. Law, Nic Scott, Samuel Halverson, R. Paul Butler, J. M. Almenara, Thomas Barclay, MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology (MIT), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Technische Universität Berlin (TU), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Smithsonian Institution-Harvard University [Cambridge], Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Radial velocity (1332), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, 010309 optics, Telescope, Neptune, law, Planet, Observatory, 0103 physical sciences, Transit photometry (1709), Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Exoplanets (498), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Orbital period, Exoplanet, Radial velocity, Planetary science, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Planetary system formation (1257), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby ($d$ = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite and followed up with observations from the Las Cumbres Observatory and the Antarctica Search for Transiting ExoPlanets program. Combining the photometric data sets, we find that the newly discovered planet has a radius of 3.65$^{+0.16}_{-0.15}$ R$_{\oplus}$, and an orbital period of 24.246 days. Radial velocity measurements obtained with the Planet Finder Spectrograph on the Magellan Clay telescope confirm the existence of the planet and lead to a mass measurement of 15.5$\pm$3.3 M$_{\oplus}$. With an equilibrium temperature of just 330K TOI-1231 b is one of the coolest small planets accessible for atmospheric studies thus far, and its host star's bright NIR brightness (J=8.88, K$_{s}$=8.07) make it an exciting target for HST and JWST. Future atmospheric observations would enable the first comparative planetology efforts in the 250-350 K temperature regime via comparisons with K2-18 b. Furthermore, TOI-1231's high systemic radial velocity (70.5 k\ms) may allow for the detection of low-velocity hydrogen atoms escaping the planet by Doppler shifting the H I Ly-alpha stellar emission away from the geocoronal and ISM absorption features., 20 pages, 9 figures. Accepted for publication in The Astronomical Journal

Published
2021

Catalog

Books, media, physical & digital resources
See catalog results