14 results on '"Laura Vican"'
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2. Nearby Young, Active, Late-type Dwarfs in Gaia's First Data Release
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Kastner, Joel H., Sacco, Germano, Rodriguez, David, Punzi, Kristina, Zuckerman, B., and Haney, Laura Vican
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Astrophysics - Solar and Stellar Astrophysics - Abstract
The Galex Nearby Young Star Survey (GALNYSS) has yielded a sample of $\sim$2000 UV-selected objects that are candidate nearby ($D \stackrel{<}{\sim}$150 pc), young (age $\sim$10--100 Myr), late-type stars. Here, we evaluate the distances and ages of the subsample of (19) GALNYSS stars with Gaia Data Release 1 (DR1) parallax distances $D \le 120$ pc. The overall youth of these 19 mid-K to early-M stars is readily apparent from their positions relative to the loci of main sequence stars and giants in Gaia-based color-magnitude and color-color diagrams constructed for all Galex- and WISE-detected stars with parallax measurements included in DR1. The isochronal ages of all 19 stars lie in the range $\sim$10--100 Myr. Comparison with Li-based age estimates indicates a handful of these stars may be young main-sequence binaries rather than pre-main sequence stars. Nine of the 19 objects have not previously been considered as nearby, young stars, and all but one of these are found at declinations north of $+$30$^\circ$. The Gaia DR1 results presented here indicate that the GALNYSS sample includes several hundred nearby, young stars, a substantial fraction of which have not been previously recognized as having ages $\stackrel{<}{\sim}$100 Myr., Comment: 30 pages, 4 tables, 7 figures; to appear in The Astrophysical Journal; 1st replacement to correct typos/omissions in Table 3 and acknowledgments; 2nd replacement to incorporate corrections to ApJ proofs
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- 2017
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3. Space Telescope and Optical Reverberation Mapping Project. IX. Velocity–Delay Maps for Broad Emission Lines in NGC 5548
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B. J. Shappee, J. M. Gelbord, Alessandro Siviero, Marianne Vestergaard, M. Spencer, G. A. Borman, Kevin V. Croxall, Michael Fausnaugh, Rick Edelson, M. C. Bottorff, Yair Krongold, Jeremy Jones, A. Skielboe, Nicolas Tejos, T. Hutchison, F. MacInnis, J. E. Brown, Catherine J. Grier, Hyun-Il Sung, M. L. Nguyen, Ryan Norris, Alis J. Deason, Haojing Yan, Susanna Bisogni, D. M. Crenshaw, J. A. Kennea, Alexei V. Filippenko, P. Ochner, S. V. Nazarov, A. A. Breeveld, Keith Horne, I. M. McHardy, Y. Weiss, E. Holmbeck, Wei Zhu, Michael T. Carini, J. A. Nousek, Hagai Netzer, A. Bigley, S. Hicks, Michael D. Joner, Kirk T. Korista, S. A. Klimanov, S. C. Kim, G. De Rosa, Jon C. Mauerhan, E. R. Manne-Nicholas, J. van Saders, Isaac Shivvers, Aaron J. Barth, Christopher S. Kochanek, Vardha N. Bennert, Ying Zu, Sang Chul Kim, Kelly D. Denney, Scott M. Adams, S. G. Sergeev, L. Gonzalez, F. Müller Sánchez, H. Yuk, Steven Villanueva, N. Gehrels, J. J. Jensen, R. McGurk, M. Im, Miao Li, K. Flatland, Garrett Somers, Jamie Tayar, D. Mudd, S. Geier, Enrico Maria Corsini, Phil Uttley, S. Rafter, M. Eracleous, H. W. Rix, Lorenzo Morelli, Douglas C. Leonard, Kelsey I. Clubb, Laura Vican, K. Schnülle, Smita Mathur, C. S. Turner, J. R. Parks, J.-U. Pott, M. Dietrich, Patrick L. Kelly, Jenny E. Greene, Carolin Villforth, P. Arévalo, Calen B. Henderson, Michael S. Brotherton, A. Gupta, M. W. Lau, Julia M. Comerford, Chris Done, Minjin Kim, Ori D. Fox, Gerard A. Kriss, Gary J. Ferland, Daniel Proga, S. Young, N. V. Efimova, Thomas W.-S. Holoien, P. A. Evans, Radosław Poleski, M. R. Goad, Dirk Grupe, B. Scott, Alessandro Pizzella, Zhiyuan Ma, J. S. Schimoia, J. C. Lee, Jong-Hak Woo, P. Lira, Cassandra Lochhaas, Jessie C. Runnoe, M. H. Siegel, Justin Ely, Patrick B. Hall, I. E. Papadakis, C. A. Johnson, Tommaso Treu, Emma Gardner, Todd Boroson, D. A. Starkey, Daniel J. Stevens, Thomas G. Beatty, Andrew J. King, Jelle Kaastra, Edward M. Cackett, Misty C. Bentz, J. S. Brown, Liuyi Pei, D. N. Okhmat, Steve Croft, M. A. Malkan, G. V. Simonian, M. Dehghanian, C. Montuori, Bradley M. Peterson, E. Dalla Bontà, R. W. Pogge, Matthew T. Penny, V. Gorjian, W. N. Brandt, Elinor L. Gates, Shai Kaspi, D. A. Saylor, Ana M. Mosquera, A. Pancoast, WeiKang Zheng, A. de Lorenzo-Cáceres, Gabriela Canalizo, ITA, USA, GBR, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, and University of St Andrews. St Andrews Centre for Exoplanet Science
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Seyfert [Galaxies] ,Active galactic nucleus ,active [Galaxies] ,010504 meteorology & atmospheric sciences ,individual (NGC 5548) [Galaxies] ,Active galaxies, Astrophysical black holes, Supermassive black holes, Active galactic nuclei, Reverberation mapping ,astro-ph.GA ,T-NDAS ,FOS: Physical sciences ,Astrophysics ,Astronomy & Astrophysics ,01 natural sciences ,Atomic ,Physical Chemistry ,Virial theorem ,Reverberation mapping ,Particle and Plasma Physics ,Spitzer Space Telescope ,Supermassive black holes ,0103 physical sciences ,QB Astronomy ,Nuclear ,Emission spectrum ,010303 astronomy & astrophysics ,QC ,QB ,0105 earth and related environmental sciences ,Line (formation) ,Physics ,Active galactic nuclei ,Supermassive black hole ,Astrophysical black holes ,Molecular ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Black hole ,QC Physics ,Space and Planetary Science ,nuclei [Galaxies] ,Astrophysics of Galaxies (astro-ph.GA) ,Active galaxies ,Astronomical and Space Sciences ,Physical Chemistry (incl. Structural) - Abstract
We report velocity-delay maps for prominent broad emission lines, Ly_alpha, CIV, HeII and H_beta, in the spectrum of NGC5548. The emission-line responses inhabit the interior of a virial envelope. The velocity-delay maps reveal stratified ionization structure. The HeII response inside 5-10 light-days has a broad single-peaked velocity profile. The Ly_alpha, CIV, and H_beta responses peak inside 10 light-days, extend outside 20 light-days, and exhibit a velocity profile with two peaks separated by 5000 km/s in the 10 to 20 light-day delay range. The velocity-delay maps show that the M-shaped lag vs velocity structure found in previous cross-correlation analysis is the signature of a Keplerian disk with a well-defined outer edge at R=20 light-days. The outer wings of the M arise from the virial envelope, and the U-shaped interior of the M is the lower half of an ellipse in the velocity-delay plane. The far-side response is weaker than that from the near side, so that we see clearly the lower half, but only faintly the upper half, of the velocity--delay ellipse. The delay tau=(R/c)(1-sin(i))=5 light-days at line center is from the near edge of the inclined ring, giving the inclination i=45 deg. A black hole mass of M=7x10^7 Msun is consistent with the velocity-delay structure. A barber-pole pattern with stripes moving from red to blue across the CIV and possibly Ly_alpha line profiles suggests the presence of azimuthal structure rotating around the far side of the broad-line region and may be the signature of precession or orbital motion of structures in the inner disk. Further HST observations of NGC 5548 over a multi-year timespan but with a cadence of perhaps 10 days rather than 1 day could help to clarify the nature of this new AGN phenomenon., 19 pages, 9 figures, ApJ in press
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- 2021
4. Space Telescope and Optical Reverberation Mapping Project. XII: Broad-line Region Modeling of NGC 5548
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Christopher S. Kochanek, T. Hutchison, H. W. Rix, Gary J. Ferland, Alessandro Pizzella, E. Holmbeck, E. R. Manne-Nicholas, Ori D. Fox, Radosław Poleski, I. E. Papadakis, Erin Kara, S. Young, Vardha N. Bennert, Kelly D. Denney, Daniel J. Stevens, M. Dietrich, Calen B. Henderson, WeiKang Zheng, Haojing Yan, Aaron J. Barth, P. Lira, M. C. Bottorff, Steve Croft, Jelle Kaastra, Jamie Tayar, Misty C. Bentz, Zhiyuan Ma, Laura Vican, Jenny E. Greene, J. S. Brown, M. W. Lau, F. Müller-Sánchez, Alexei V. Filippenko, Dirk Grupe, Daniel Proga, R. McGurk, Alis J. Deason, I. M. McHardy, K. Flatland, Matthew A. Malkan, Michael D. Joner, Douglas C. Leonard, Kelsey I. Clubb, Missagh Mehdipour, B. J. Shappee, Kevin V. Croxall, J. M. Gelbord, M. H. Siegel, Jon C. Mauerhan, Ying Zu, Patrick L. Kelly, Christian Knigge, Myungshin Im, Peter R. Williams, C. A. Johnson, S. V. Nazarov, J. A. Nousek, Miao Li, C. S. Turner, Andrew J. King, Marianne Vestergaard, S. C. Kim, G. De Rosa, J. R. Parks, M. Spencer, S. G. Sergeev, Steven Villanueva, Matthew T. Penny, Lorenzo Morelli, Jong-Hak Woo, D. Mudd, D. M. Crenshaw, J.-U. Pott, T. W. S. Holoien, A. A. Breeveld, D. N. Okhmat, Scott M. Adams, Carolin Villforth, Sang Chul Kim, V. Gorjian, W. N. Brandt, G. V. Simonian, Elinor L. Gates, Shai Kaspi, M. Dehghanian, D. A. Saylor, Hyun-Il Sung, Simon Vaughan, Isaac Shivvers, F. MacInnis, Minjin Kim, Edward M. Cackett, Liuyi Pei, Alessandro Siviero, Cassandra Lochhaas, Patrick B. Hall, Wei Zhu, Tommaso Treu, Thomas G. Beatty, Tim Waters, B. Scott, J. C. Lee, Jeremy Jones, M. L. Nguyen, Ryan Norris, Susanna Bisogni, Justin Ely, Keith Horne, A. Gupta, L. Gonzalez, J. J. Jensen, P. Arévalo, N. Gehrels, Catherine J. Grier, S. Geier, Enrico Maria Corsini, S. E. Rafter, P. Ochner, Y. Weiss, A. Skielboe, Michael T. Carini, Michael S. Brotherton, H. Yuk, Chris Done, Gerard A. Kriss, C. Montuori, Bradley M. Peterson, E. Dalla Bontà, Emma Gardner, D. A. Starkey, R. W. Pogge, Smita Mathur, J. A. Kennea, P. A. Evans, A. Bigley, Jessie C. Runnoe, S. Hicks, S. A. Klimanov, Todd Boroson, J. van Saders, J. S. Schimoia, Garrett Somers, Phil Uttley, Nahum Arav, G. A. Borman, J. E. Brown, Nicolas Tejos, Julia M. Comerford, A. de Lorenzo-Cáceres, Gabriela Canalizo, Ana M. Mosquera, A. Pancoast, Michael Fausnaugh, Rick Edelson, N. V. Efimova, Brendon J. Brewer, Yair Krongold, High Energy Astrophys. & Astropart. Phys (API, FNWI), University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, ITA, USA, and GBR
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010504 meteorology & atmospheric sciences ,Active galaxies, Active galactic nuclei, Reverberation mapping, Seyfert galaxies ,Astrophysics ,01 natural sciences ,Atomic ,Particle and Plasma Physics ,Reverberation mapping ,Spitzer Space Telescope ,Emission spectrum ,010303 astronomy & astrophysics ,QC ,Physics ,Seyfert galaxies ,Balmer series ,3rd-DAS ,VARIABILITY ,Reverbation mapping ,AGN MONITORING PROJECT ,symbols ,STEPS ,Astronomical and Space Sciences ,Physical Chemistry (incl. Structural) ,Active galactic nucleus ,astro-ph.GA ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astronomy & Astrophysics ,Electromagnetic radiation ,symbols.namesake ,SUPERMASSIVE BLACK-HOLES ,0103 physical sciences ,Nuclear ,MASSES ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Active galactic nuclei ,Molecular ,Astronomy and Astrophysics ,Light curve ,Astrophysics - Astrophysics of Galaxies ,Black hole ,CONTINUUM ,SIZE ,QC Physics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Active galaxies ,EMISSION - Abstract
We present geometric and dynamical modeling of the broad line region for the multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The dataset includes photometric and spectroscopic monitoring in the optical and ultraviolet, covering the H$\beta$, C IV, and Ly$\alpha$ broad emission lines. We find an extended disk-like H$\beta$ BLR with a mixture of near-circular and outflowing gas trajectories, while the C IV and Ly$\alpha$ BLRs are much less extended and resemble shell-like structures. There is clear radial structure in the BLR, with C IV and Ly$\alpha$ emission arising at smaller radii than the H$\beta$ emission. Using the three lines, we make three independent black hole mass measurements, all of which are consistent. Combining these results gives a joint inference of $\log_{10}(M_{\rm BH}/M_\odot) = 7.64^{+0.21}_{-0.18}$. We examine the effect of using the $V$ band instead of the UV continuum light curve on the results and find a size difference that is consistent with the measured UV-optical time lag, but the other structural and kinematic parameters remain unchanged, suggesting that the $V$ band is a suitable proxy for the ionizing continuum when exploring the BLR structure and kinematics. Finally, we compare the H$\beta$ results to similar models of data obtained in 2008 when the AGN was at a lower luminosity state. We find that the size of the emitting region increased during this time period, but the geometry and black hole mass remain unchanged, which confirms that the BLR kinematics suitably gauge the gravitational field of the central black hole., Comment: 26 pages, 19 figures, 1 table, accepted for publication in ApJ
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- 2020
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5. Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum
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Andrew J. King, K. G. Teems, Gabriele Ponti, J. S. Schimoia, Calen B. Henderson, Michael S. Brotherton, S. Paltani, Nahum Arav, Alessandro Siviero, Radosław Poleski, P. Lira, Sang Chul Kim, Thomas W.-S. Holoien, Wei Zhu, A. de Lorenzo-Cáceres, M. C. Bottorff, Dirk Grupe, Gabriela Canalizo, M. Eracleous, S. G. Sergeev, F. MacInnis, Massimo Cappi, M. Dietrich, Alis J. Deason, Haojing Yan, Giorgio Matt, Ciro Pinto, Michael T. Carini, Minjin Kim, Brandon C. Kelly, I. M. McHardy, Scott M. Adams, L. Gonzalez, J. J. Jensen, Julia M. Comerford, Yair Krongold, Tim Waters, B. Scott, C. S. Turner, G. A. Borman, R. McGurk, Nicolas Tejos, J. R. Parks, K. Flatland, Michael D. Joner, Kirk T. Korista, L. Di Gesu, Emma Gardner, Jon C. Mauerhan, Jessie C. Runnoe, Douglas C. Leonard, Kelsey I. Clubb, M. H. Siegel, C. A. Johnson, D. A. Starkey, H. Yuk, M. A. Malkan, Justin Ely, Ying Zu, Aaron J. Barth, Cassandra Lochhaas, Patrick L. Kelly, E. Holmbeck, Hyun-Il Sung, Patrick B. Hall, C. Montuori, Christopher S. Kochanek, Bradley M. Peterson, Tommaso Treu, Missagh Mehdipour, Marie Wingyee Lau, A. Skielboe, Catherine J. Grier, J. A. Kennea, Thomas G. Beatty, R. W. Pogge, J. van Saders, A. Bigley, S. Hicks, Catia Silva, H. W. Rix, Vardha N. Bennert, D. M. Crenshaw, E. Dalla Bontà, Miao Li, A. A. Breeveld, Dom Walton, D. N. Okhmat, Elisa Costantini, P. Ochner, Y. Weiss, M. L. Nguyen, Ryan Norris, Susanna Bisogni, Ehud Behar, Jacobo Ebrero, Garrett Somers, Phil Uttley, S. Rafter, Kelly D. Denney, K. Schnülle, Carolin Villforth, Keith Horne, Smita Mathur, G. V. Simonian, R. Boissay-Malaquin, Gary J. Ferland, J. S. Brown, Jelle Kaastra, Ana M. Mosquera, Stefano Bianchi, Misty C. Bentz, A. Pancoast, Alessandro Pizzella, WeiKang Zheng, N. Gehrels, Daniel J. Stevens, M. Dehghanian, Kevin V. Croxall, Isaac Shivvers, A. Gupta, Chris Done, J. E. Brown, B. De Marco, Gerard A. Kriss, Steve Croft, S. V. Nazarov, J. A. Nousek, Jae-Ok Lee, P. Arévalo, G. De Rosa, Michael Fausnaugh, Rick Edelson, Phil Evans, Lorenzo Morelli, S. Geier, Enrico Maria Corsini, M. R. Goad, V. Gorjian, W. N. Brandt, Elinor L. Gates, Shai Kaspi, D. A. Saylor, Jong-Hak Woo, Edward M. Cackett, Liuyi Pei, T. Hutchison, Jamie Tayar, E. R. Manne-Nicholas, Laura Vican, Daniel Proga, Steven Villanueva, D. Mudd, J.-U. Pott, F. Müller-Sánchez, Alexei V. Filippenko, Hagai Netzer, S. A. Klimanov, B. J. Shappee, J. M. Gelbord, Marianne Vestergaard, M. Spencer, Zhiyuan Ma, Carl T. Coker, S. Y. Kim, Myungshin Im, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, High Energy Astrophys. & Astropart. Phys (API, FNWI), Kriss, G. A., De Rosa, G., Ely, J., Peterson, B. M., Kaastra, J., Mehdipour, M., Ferland, G. J., Dehghanian, M., Mathur, S., Edelson, R., Korista, K. T., Arav, N., Barth, A. J., Bentz, M. C., Brandt, W. N., Crenshaw, D. M., Bontà, E. Dalla, Denney, K. D., Done, C., Eracleous, M., Fausnaugh, M. M., Gardner, E., Goad, M. R., Grier, C. J., Horne, Keith, Kochanek, C. S., Mchardy, I. M., Netzer, H., Pancoast, A., Pei, L., Pogge, R. W., Proga, D., Silva, C., Tejos, N., Vestergaard, M., Adams, S. M., Anderson, M. D., Arévalo, P., Beatty, T G., Behar, E., Bennert, V. N., Bianchi, S., Bigley, A., Bisogni, S., Boissay-Malaquin, R., Borman, G. A., Bottorff, M. C., Breeveld, A. A., Brotherton, M., Brown, J. E., Brown, J. S., Cackett, E. M., Canalizo, G., Cappi, M., Carini, M. T., Clubb, K. I., Comerford, J. M., Coker, C. T., Corsini, E. M., Costantini, E., Croft, S., Croxall, K. V., Deason, A. J., De Lorenzo-Cáceres, A., De Marco, B., Dietrich, M., Di Gesu, L., Ebrero, J., Evans, P. A., Filippenko, A. V., Flatland, K., Gates, E. L., Gehrels, N., Geier, S., Gelbord, J. M., Gonzalez, L., Gorjian, V., Grupe, D., Gupta, A., Hall, P. B., Henderson, C. B., Hicks, S., Holmbeck, E., Holoien, T. W. -S., Hutchison, T. A., Im, M., Jensen, J. J., Johnson, C. A., Joner, M. D., Kaspi, S., Kelly, B. C., Kelly, P. L., Kennea, J. A., Kim, M., Kim, S. C., Kim, S. Y., King, A., Klimanov, S. A., Krongold, Y., Lau, M. W., Lee, J. C., Leonard, D. C., Li, Miao, Lira, P., Lochhaas, C., Ma, Zhiyuan, Macinnis, F., Malkan, M. A., Manne-Nicholas, E. R., Matt, G., Mauerhan, J. C., Mcgurk, R., Montuori, C., Morelli, L., Mosquera, A., Mudd, D., Müller-Sánchez, F., Nazarov, S. V., Norris, R. P., Nousek, J. A., Nguyen, M. L., Ochner, P., Okhmat, D. N., Paltani, S., Parks, J. R., Pinto, C., Pizzella, A., Poleski, R., Ponti, G., Pott, J. -U., Rafter, S. E., Rix, H. -W., Runnoe, J., Saylor, D. A., Schimoia, J. S., Schnülle, K., Scott, B., Sergeev, S. G., Shappee, B. J., Shivvers, I., Siegel, M., Simonian, G. V., Siviero, A., Skielboe, A., Somers, G., Spencer, M., Starkey, D., Stevens, D. J., Sung, H. -I., Tayar, J., Teems, K. G., Treu, T., Turner, C. S., Uttley, P., Van Saders, J ., Vican, L., Villforth, C., Villanueva Jr., S., Walton, D. J., Waters, T., Weiss, Y., Woo, J. -H., Yan, H., Yuk, H., Zheng, W., Zhu, W., Zu, Y., and USA
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Seyfert [Galaxies] ,galaxies: active ,galaxies: individual (NGC 5548) ,galaxies: nuclei ,galaxies: Seyfert ,010504 meteorology & atmospheric sciences ,Absorption spectroscopy ,active [Galaxies] ,individual (NGC 5548) [Galaxies] ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Spectral line ,Luminosity ,0103 physical sciences ,QB Astronomy ,Emission spectrum ,Absorption (electromagnetic radiation) ,010303 astronomy & astrophysics ,QC ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,QB ,Physics ,Astronomy and Astrophysics ,DAS ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,QC Physics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,nuclei [Galaxies] ,Reverberation mapping - Abstract
We model the ultraviolet spectra of the Seyfert 1 galaxy NGC~5548 obtained with the Hubble Space Telescope during the 6-month reverberation-mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Ly$\alpha$ and C IV, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. The velocity-binned lag profiles of Ly$\alpha$ and C IV have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show delayed response to continuum variations corresponding to recombination in gas with a density of $\sim 10^5~\rm cm^{-3}$. The high-ionization narrow absorption lines decorrelate from continuum variations during the same period as the broad emission lines. Analyzing the response of these absorption lines during this period shows that the ionizing flux is diminished in strength relative to the far-ultraviolet continuum. The broad absorption lines associated with the X-ray obscurer decrease in strength during this same time interval. The appearance of X-ray obscuration in $\sim\,2012$ corresponds with an increase in the luminosity of NGC 5548 following an extended low state. We suggest that the obscurer is a disk wind triggered by the brightening of NGC 5548 following the decrease in size of the broad-line region during the preceding low-luminosity state., Comment: 50 pages, 30 figures, uses aastex62.cls. Accepted for publication in ApJ, 07/06/2019. High-level products page in MAST will go live after 7/15/2019. Replaced Figure 4 on 7/12/2019 to be more red/green color-blind friendly
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- 2019
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6. SONS: The JCMT legacy survey of debris discs in the submillimetre
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W. R. F. Dent, Glenn J. White, P. van der Werf, J. Di Francesco, Ben Zuckerman, Wayne S. Holland, Gaspard Duchêne, Pierre Bastien, Claire L. Davies, C. Chen, Grant M. Kennedy, Mark C. Wyatt, Amaya Moro-Martin, Brenda C. Matthews, N. Phillips, Per Friberg, T. Jenness, Andy Gibb, Derek Ward-Thompson, Laura Vican, Bruce Sibthorpe, Jane Greaves, G. Bryden, Mark Booth, Harold M. Butner, G. Schieven, David J. Wilner, Stephen Serjeant, Samantha Lawler, Rob Ivison, J.-F. Lestrade, Jonathan P. Marshall, Antonio Chrysostomou, Jj Kavelaars, O. Panić, Space Telescope Science Institute (STSci), National Research Council of Canada (NRC), Royal Observatory Edinburgh (ROE), University of Edinburgh, Observatoire de Paris, Université Paris sciences et lettres (PSL), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Kennedy, Grant [0000-0001-6831-7547], Wyatt, Mark [0000-0001-9064-5598], and Apollo - University of Cambridge Repository
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Library science ,FOS: Physical sciences ,F500 ,Astrophysics::Cosmology and Extragalactic Astrophysics ,circumstellar matter ,01 natural sciences ,0103 physical sciences ,media_common.cataloged_instance ,Astrophysics::Solar and Stellar Astrophysics ,14. Life underwater ,European union ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,media_common ,QB ,[PHYS]Physics [physics] ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Joint Astronomy Centre ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Vice chancellor ,submillimetre: stars ,Astrophysics - Solar and Stellar Astrophysics ,13. Climate action ,Space and Planetary Science ,Research council ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Debris discs are evidence of the ongoing destructive collisions between planetesimals, and their presence around stars also suggests that planets exist in these systems. In this paper, we present submillimetre images of the thermal emission from debris discs that formed the SCUBA-2 Observations of Nearby Stars (SONS) survey, one of seven legacy surveys undertaken on the James Clerk Maxwell telescope between 2012 and 2015. The overall results of the survey are presented in the form of 850 microns (and 450 microns, where possible) images and fluxes for the observed fields. Excess thermal emission, over that expected from the stellar photosphere, is detected around 49 stars out of the 100 observed fields. The discs are characterised in terms of their flux density, size (radial distribution of the dust) and derived dust properties from their spectral energy distributions. The results show discs over a range of sizes, typically 1-10 times the diameter of the Edgeworth-Kuiper Belt in our Solar System. The mass of a disc, for particles up to a few millimetres in size, is uniquely obtainable with submillimetre observations and this quantity is presented as a function of the host stars' age, showing a tentative decline in mass with age. Having doubled the number of imaged discs at submillimetre wavelengths from ground-based, single dish telescope observations, one of the key legacy products from the SONS survey is to provide a comprehensive target list to observe at high angular resolution using submillimetre/millimetre interferometers (e.g., ALMA, SMA)., 61 pages, 51 figures
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- 2017
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7. Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-line Analysis for NGC 5548
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S. Young, Brandon C. Kelly, J.-U. Pott, T. Hutchison, Scott M. Adams, E. Holmbeck, A. A. Breeveld, Jelle Kaastra, S. E. Rafter, Misty C. Bentz, G. A. Borman, P. Arévalo, D. A. Starkey, Michael T. Carini, I. E. Papadakis, M. Dietrich, Alis J. Deason, I. M. McHardy, Vardha N. Bennert, Kelly D. Denney, Michael D. Joner, Gabriela Canalizo, Justin Ely, A. Pancoast, Catherine J. Grier, D. C. Leonard, P. Ochner, Ying Zu, Zhiyuan Ma, A. Skielboe, J. van Saders, Bryan Scott, D. Horenstein, J. A. Kennea, Carl T. Coker, W. N. Brandt, A. Gupta, H. Yuk, D. Grupe, M. C. Bottorff, Michael Fausnaugh, Myungshin Im, Marianne Vestergaard, Rick Edelson, K. Schnülle, M. Spencer, Sang Chul Kim, C. Montouri, Miao Li, J. J. Jensen, W. Zheng, Nadia L. Zakamska, Gary J. Ferland, Ana M. Mosquera, N. V. Efimova, Steve Croft, Jenny E. Greene, Michael Eracleous, A. de Lorenzo-Cáceres, M. R. Goad, D. A. Saylor, Richard W. Pogge, Calen B. Henderson, Radosław Poleski, Jessie C. Runnoe, Carolin Villforth, G. De Rosa, A. V. Filippenko, Ori D. Fox, M. W. Lau, Thomas W.-S. Holoien, Michael S. Brotherton, H. Yan, Kirk T. Korista, C. Bazhaw, E. M. Cackett, B. Ou-Yang, Hagai Netzer, K. G. Teems, Michael A. Strauss, Aaron J. Barth, Alessandro Pizzella, Jon C. Mauerhan, Steven Villanueva, Christopher S. Kochanek, J. C. Lee, R. McGurk, M. H. Siegel, K. Flatland, F. Muller Sanchez, D. Mudd, Nicolas Tejos, Elinor L. Gates, P. Lira, Kelsey I. Clubb, S. V. Nazarov, Lorenzo Morelli, R. Musso, Cassandra Lochhaas, Patrick B. Hall, H.-I. Sung, Matthew T. Penny, Tommaso Treu, D. M. Crenshaw, H.-W. Rix, Bradley M. Peterson, Daniel J. Stevens, D. N. Okhmat, Patrick L. Kelly, Thomas G. Beatty, M. L. Nguyen, Ryan Norris, S. Mathur, Susanna Bisogni, Isaac Shivvers, S. Geier, Keith Horne, Phil Evans, G. V. Simonian, E. Dalla Bontà, Benjamin J. Shappee, A. L. King, Shai Kaspi, Enrico Maria Corsini, G. A. Kriss, C. S. Turner, J. R. Parks, Y. Weiss, M. Malkan, E. R. Manne-Nicholas, Jonathan Gelbord, Alessandro Siviero, Wei Zhu, S. G. Sergeev, F. MacInnis, Minjin Kim, J. A. Nousek, Cassidy Johnson, J. S. Brown, A. Bigley, S. Hicks, Julia M. Comerford, J. D. Jones, J. S. Schimoia, Jamie Tayar, K. V. Croxall, Laura Vican, Jong-Hak Woo, Garrett Somers, Phil Uttley, Liuyi Pei, N. Gehrels, J. E. Brown, Stacy Y. Kim, S. A. Klimanov, USA, Science & Technology Facilities Council, University of St Andrews. School of Physics and Astronomy, University of St Andrews. St Andrews Centre for Exoplanet Science, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
- Subjects
Doubly ionized oxygen ,NDAS ,nuclei [galaxies] ,FOS: Physical sciences ,Astrophysics ,Expected value ,galaxies: active - galaxies: individual (NGC 5548) - galaxies: nuclei - galaxies: Seyfert ,medicine.disease_cause ,01 natural sciences ,Spitzer Space Telescope ,Seyfert [galaxies] ,0103 physical sciences ,medicine ,QB Astronomy ,Emission spectrum ,010303 astronomy & astrophysics ,QC ,QB ,Physics ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Light curve ,Astrophysics - Astrophysics of Galaxies ,Monitoring program ,QC Physics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,individual (NGC 5548) [galaxies] ,Reverberation mapping ,Ultraviolet - Abstract
We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multi-wavelength reverberation mapping campaign. The campaign spanned six months and achieved an almost daily cadence with observations from five ground-based telescopes. The H$\beta$ and He II $\lambda$4686 broad emission-line light curves lag that of the 5100 $\AA$ optical continuum by $4.17^{+0.36}_{-0.36}$ days and $0.79^{+0.35}_{-0.34}$ days, respectively. The H$\beta$ lag relative to the 1158 $\AA$ ultraviolet continuum light curve measured by the Hubble Space Telescope is roughly $\sim$50% longer than that measured against the optical continuum, and the lag difference is consistent with the observed lag between the optical and ultraviolet continua. This suggests that the characteristic radius of the broad-line region is $\sim$50% larger than the value inferred from optical data alone. We also measured velocity-resolved emission-line lags for H$\beta$ and found a complex velocity-lag structure with shorter lags in the line wings, indicative of a broad-line region dominated by Keplerian motion. The responses of both the H$\beta$ and He II $\lambda$4686 emission lines to the driving continuum changed significantly halfway through the campaign, a phenomenon also observed for C IV, Ly $\alpha$, He II(+O III]), and Si IV(+O IV]) during the same monitoring period. Finally, given the optical luminosity of NGC 5548 during our campaign, the measured H$\beta$ lag is a factor of five shorter than the expected value implied by the $R_\mathrm{BLR} - L_\mathrm{AGN}$ relation based on the past behavior of NGC 5548., Comment: 22 pages, 13 figures, accepted to ApJ
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- 2017
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8. Solar Abundances of Rock Forming Elements, Extreme Oxygen and Hydrogen in a Young Polluted White Dwarf
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Ben Zuckerman, Boris T. Gänsicke, Gregory Walth, Elmé Breedt, Jay Farihi, Nathan Smith, Detlev Koester, and Laura Vican
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Hydrogen ,FOS: Physical sciences ,chemistry.chemical_element ,7. Clean energy ,01 natural sciences ,Astrobiology ,0103 physical sciences ,media_common.cataloged_instance ,Astrophysics::Solar and Stellar Astrophysics ,European union ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,QC ,Astrophysics::Galaxy Astrophysics ,QB ,media_common ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,010308 nuclear & particles physics ,White dwarf ,Astronomy ,Astronomy and Astrophysics ,chemistry ,Astrophysics - Solar and Stellar Astrophysics ,13. Climate action ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Teff = 20,800 K white dwarf WD 1536+520 is shown to have broadly solar abundances of the major rock forming elements O, Mg, Al, Si, Ca, and Fe, together with a strong relative depletion in the volatile elements C and S. In addition to the highest metal abundances observed to date, including log(O/He) = -3.4, the helium-dominated atmosphere has an exceptional hydrogen abundance at log(H/He) = -1.7. Within the uncertainties, the metal-to-metal ratios are consistent with the accretion of an H2O-rich and rocky parent body, an interpretation supported by the anomalously high trace hydrogen. The mixed atmosphere yields unusually short diffusion timescales for a helium atmosphere white dwarf, of no more than a few hundred yr, and equivalent to those in a much cooler, hydrogen-rich star. The overall heavy element abundances of the disrupted parent body deviate modestly from a bulk Earth pattern, and suggest the deposition of some core-like material. The total inferred accretion rate is 4.2e9 g/s, and at least 4 times higher than any white dwarf with a comparable diffusion timescale. Notably, when accretion is exhausted in this system, both metals and hydrogen will become undetectable within roughly 300 Myr, thus supporting a scenario where the trace hydrogen is related to the ongoing accretion of planetary debris., To be published in MNRAS
- Published
- 2016
9. Circumstellar Debris Disks: Diagnosing the Unseen Perturber
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Erika R. Nesvold, Will M. Farr, Laura Vican, and Smadar Naoz
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,education.field_of_study ,Debris disk ,010308 nuclear & particles physics ,Population ,Brown dwarf ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Planetary system ,01 natural sciences ,Debris ,Celestial mechanics ,Space and Planetary Science ,Planet ,Excited state ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The first indication of the presence of a circumstellar debris disk is usually the detection of excess infrared emission from the population of small dust grains orbiting the star. This dust is short-lived, requiring continual replenishment, and indicating that the disk must be excited by an unseen perturber. Previous theoretical studies have demonstrated that an eccentric planet orbiting interior to the disk will stir the larger bodies in the belt and produce dust via interparticle collisions. However, motivated by recent observations, we explore another possible mechanism for heating a debris disk: a stellar-mass perturber orbiting exterior to and inclined to the disk and exciting the disk particles' eccentricities and inclinations via the Kozai-Lidov mechanism. We explore the consequences of an exterior perturber on the evolution of a debris disk using secular analysis and collisional N-body simulations. We demonstrate that a Kozai-Lidov excited disk can generate a dust disk via collisions and we compare the results of the Kozai-Lidov excited disk with a simulated disk perturbed by an interior eccentric planet. Finally, we propose two observational tests of a dust disk that can distinguish whether the dust was produced by an exterior brown dwarf or stellar companion or an interior eccentric planet., 14 pages, 9 figures, submitted to ApJ. Comments welcome
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- 2016
10. Nearby Young, Active, Late-type Dwarfs inGaia's First Data Release
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Kastner, Joel H., primary, Sacco, Germano, additional, Rodriguez, David, additional, Punzi, Kristina, additional, Zuckerman, B., additional, and Haney, Laura Vican, additional
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- 2017
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11. Constraining X-ray-Induced Photoevaporation of Protoplanetary Disks Orbiting Low-Mass Stars
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Kristina Punzi, Laura Vican, David A. Principe, Joel H. Kastner, and David R. Rodriguez
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Physics ,Astrophysics::High Energy Astrophysical Phenomena ,X-ray ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Radiation ,Photoevaporation ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Low Mass ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Sequence (medicine) - Abstract
Low-mass, pre-main sequence stars possess intense high-energy radiation fields as a result of their strong stellar magnetic activity. This stellar UV and X-ray radiation may have a profound impact on the lifetimes of protoplanetary disks. We aim to constrain the X-ray-induced photoevaporation rates of protoplanetary disks orbiting low-mass stars by analyzing serendipitous XMM-Newton and Chandra X-ray observations of candidate nearby (D $, Comment: 2 pages, 1 figure; to appear in "Young Stars and Planets Near the Sun", Proceedings of IAU Symposium No. 314 (Cambridge University Press), J.H. Kastner, B. Stelzer, S.A. Metchev, eds
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- 2015
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12. HERSCHELOBSERVATIONS OF DUSTY DEBRIS DISKS
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Inseok Song, Barry Zuckerman, Carl Melis, Geoff Bryden, Laura Vican, Joseph H. Rhee, and Adam C. Schneider
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Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Debris disk ,Spectrometer ,010308 nuclear & particles physics ,Infrared ,Spatially resolved ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Debris ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Circumstellar dust ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We present results from two Herschel observing programs using the Photodetector Array Camera and Spectrometer. During three separate campaigns, we obtained Herschel data for 24 stars at 70, 100, and 160 microns. We chose stars that were already known or suspected to have circumstellar dust based on excess infrared emission previously measured with IRAS or Spitzer, and used Herschel to examine long-wavelength properties of the dust. Fifteen stars were found to be uncontaminated by background sources, and possess infrared emission most likely due to a circumstellar debris disk. We analyzed the properties of these debris disks to better understand the physical mechanisms responsible for dust production and removal. Seven targets were spatially resolved in the Herschel images. Based on fits to their spectral energy distributions, nine disks appear to have two temperature components. Of these nine, in three cases, the warmer dust component is likely the result of a transient process rather than a steady state collisional cascade. The dust belts at four stars are likely stirred by an unseen planet, and merit further investigation., Comment: 11 figures, 5 tables, Accepted to ApJ
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- 2016
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13. Nearby Young, Active, Late-type Dwarfs in Gaia's First Data Release.
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Joel H. Kastner, Germano Sacco, David Rodriguez, Kristina Punzi, B. Zuckerman, and Laura Vican Haney
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DWARF stars ,GIANT stars ,STAR formation ,STELLAR magnitudes - Abstract
The Galex Nearby Young Star Survey (GALNYSS) has yielded a sample of ∼2000 UV-selected objects that are candidate nearby (), young (age ∼ 10–100 Myr), late-type stars. Here, we evaluate the distances and ages of the subsample of (19) GALNYSS stars with Gaia Data Release 1 (DR1) parallax distances . The overall youth of these 19 mid-K to early-M stars is readily apparent from their positions relative to the loci of main-sequence stars and giants in Gaia-based color-magnitude and color-color diagrams constructed for all stars detected by Galex and the Wide-field Infrared Space Explorer for which parallax measurements are included in DR1. The isochronal ages of all 19 stars lie in the range ∼10–100 Myr. Comparison with Li-based age estimates indicates a handful of these stars may be young main-sequence binaries rather than pre-main sequence stars. Nine of the 19 objects have not previously been considered as nearby, young stars, and all but one of these are found at declinations north of +30°. The Gaia DR1 results presented here indicate that the GALNYSS sample includes several hundred nearby, young stars, a substantial fraction of which have not been previously recognized as having ages . [ABSTRACT FROM AUTHOR]
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- 2017
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14. HERSCHEL OBSERVATIONS OF DUSTY DEBRIS DISKS.
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Laura Vican, Adam Schneider, Geoff Bryden, Carl Melis, B. Zuckerman, Joseph Rhee, and Inseok Song
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- *
CIRCUMSTELLAR matter , *PLANETARY systems , *SPECTROMETERS - Abstract
We present results from two Herschel observing programs using the Photodetector Array Camera and Spectrometer. During three separate campaigns, we obtained Herschel data for 24 stars at 70, 100, and 160 μm. We chose stars that were already known or suspected to have circumstellar dust based on excess infrared (IR) emission previously measured with the InfraRed Astronomical Satellite (IRAS) or Spitzer and used Herschel to examine long-wavelength properties of the dust. Fifteen stars were found to be uncontaminated by background sources and possess IR emission most likely due to a circumstellar debris disk. We analyzed the properties of these debris disks to better understand the physical mechanisms responsible for dust production and removal. Seven targets were spatially resolved in the Herschel images. Based on fits to their spectral energy distributions, nine disks appear to have two temperature components. Of these nine, in three cases, the warmer dust component is likely the result of a transient process rather than a steady-state collisional cascade. The dust belts at four stars are likely stirred by an unseen planet and merit further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
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