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We report the discovery of two exoplanets orbiting around HD 212729 (TOI\,1052, TIC 317060587), a $T_{\rm eff}=6146$K star with V=9.51 observed by TESS in Sectors 1 and 13. One exoplanet, TOI-1052b, is Neptune-mass and transits the star, and an additional planet TOI-1052c is observed in radial velocities but not seen to transit. We confirm the planetary nature of TOI-1052b using precise radial velocity observations from HARPS and determined its parameters in a joint RV and photometry analysis. TOI-1052b has a radius of $2.87^{+0.29}_{-0.24}$ R$_{\oplus}$, a mass of $16.9\pm 1.7$ M$_{\oplus}$, and an orbital period of 9.14 days. TOI-1052c does not show any transits in the TESS data, and has a minimum mass of $34.3^{+4.1}_{-3.7}$ M$_{\oplus}$ and an orbital period of 35.8 days, placing it just interior to the 4:1 mean motion resonance. Both planets are best fit by relatively high but only marginally significant eccentricities of $0.18^{+0.09}_{-0.07}$ for planet b and $0.24^{+0.09}_{-0.08}$ for planet c. We perform a dynamical analysis and internal structure model of the planets as well as deriving stellar parameters and chemical abundances. The mean density of TOI-1052b is $3.9^{+1.7}_{-1.3}$ g cm$^{-3}$ consistent with an internal structure similar to Neptune. A nearby star is observed in Gaia DR3 with the same distance and proper motion as TOI-1052, at a sky projected separation of ~1500AU, making this a potential wide binary star system., Accepted to MNRAS. 11 pages

While the sample of confirmed exoplanets continues to increase, the population of transiting exoplanets around early-type stars is still limited. These planets allow us to investigate the planet properties and formation pathways over a wide range of stellar masses and study the impact of high irradiation on hot Jupiters orbiting such stars. We report the discovery of TOI-615b, TOI-622b, and TOI-2641b, three Saturn-mass planets transiting main sequence, F-type stars. The planets were identified by the Transiting Exoplanet Survey Satellite (TESS) and confirmed with complementary ground-based and radial velocity observations. TOI-615b is a highly irradiated ($\sim$1277 $F_{\oplus}$) and bloated Saturn-mass planet (1.69$^{+0.05}_{-0.06}$$R_{Jup}$ and 0.43$^{+0.09}_{-0.08}$$M_{Jup}$) in a 4.66 day orbit transiting a 6850 K star. TOI-622b has a radius of 0.82$^{+0.03}_{-0.03}$$R_{Jup}$ and a mass of 0.30$^{+0.07}_{-0.08}$~$M_{Jup}$ in a 6.40 day orbit. Despite its high insolation flux ($\sim$600 $F_{\oplus}$), TOI-622b does not show any evidence of radius inflation. TOI-2641b is a 0.39$^{+0.02}_{-0.04}$$M_{Jup}$ planet in a 4.88 day orbit with a grazing transit (b = 1.04$^{+0.05}_{-0.06 }$) that results in a poorly constrained radius of 1.61$^{+0.46}_{-0.64}$$R_{Jup}$. Additionally, TOI-615b is considered attractive for atmospheric studies via transmission spectroscopy with ground-based spectrographs and $\textit{JWST}$. Future atmospheric and spin-orbit alignment observations are essential since they can provide information on the atmospheric composition, formation and migration of exoplanets across various stellar types., 16 pages, 17 figures, submitted to A&A

Funding: TGW, ACC, and KH acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant ST/R003203/1. We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and Sector 38. TOI-836 is a bright (T = 8.5 mag), high proper motion (∼200 mas yr−1), low metallicity ([Fe/H]≈−0.28) K-dwarf with a mass of 0.68 ± 0.05 M⊙ and a radius of 0.67 ± 0.01 R⊙. We obtain photometric follow-up observations with a variety of facilities, and we use these data-sets to determine that the inner planet, TOI-836 b, is a 1.70 ± 0.07 R⊕ super-Earth in a 3.82 day orbit, placing it directly within the so-called ‘radius valley’. The outer planet, TOI-836 c, is a 2.59 ± 0.09 R⊕ mini-Neptune in an 8.60 day orbit. Radial velocity measurements reveal that TOI-836 b has a mass of 4.5 ± 0.9 M⊕, while TOI-836 c has a mass of 9.6 ± 2.6 M⊕. Photometric observations show Transit Timing Variations (TTVs) on the order of 20 minutes for TOI-836 c, although there are no detectable TTVs for TOI-836 b. The TTVs of planet TOI-836 c may be caused by an undetected exterior planet. Publisher PDF

Full list of authors: Wilson, Thomas G.; Goffo, Elisa; Alibert, Yann; Gandolfi, Davide; Bonfanti, Andrea; Persson, Carina M.; Collier Cameron, Andrew; Fridlund, Malcolm; Fossati, Luca; Korth, Judith; Benz, Willy; Deline, Adrien; Florén, Hans-Gustav; Guterman, Pascal; Adibekyan, Vardan; Hooton, Matthew J.; Hoyer, Sergio; Leleu, Adrien; Mustill, Alexander James; Salmon, Sébastien; Sousa, Sérgio G.; Suarez, Olga; Abe, Lyu; Agabi, Abdelkrim; Alonso, Roi; Anglada, Guillem; Asquier, Joel; Bárczy, Tamas; Barrado Navascues, David; Barros, Susana C. C.; Baumjohann, Wolfgang; Beck, Mathias; Beck, Thomas; Billot, Nicolas; Bonfils, Xavier; Brandeker, Alexis; Broeg, Christopher; Bryant, Edward M.; Burleigh, Matthew R.; Buttu, Marco; Cabrera, Juan; Charnoz, Sébastien; Ciardi, David R.; Cloutier, Ryan; Cochran, William D.; Collins, Karen A.; Colón, Knicole D.; Crouzet, Nicolas; Csizmadia, Szilard; Davies, Melvyn B.; Deleuil, Magali; Delrez, Laetitia; Demangeon, Olivier; Demory, Brice-Olivier; Dragomir, Diana; Dransfield, Georgina; Ehrenreich, David; Erikson, Anders; Fortier, Andrea; Gan, Tianjun; Gill, Samuel; Gillon, Michaël; Gnilka, Crystal L.; Grieves, Nolan; Grziwa, Sascha; Güdel, Manuel; Guillot, Tristan; Haldemann, Jonas; Heng, Kevin; Horne, Keith; Howell, Steve B.; Isaak, Kate G.; Jenkins, Jon M.; Jensen, Eric L. N.; Kiss, Laszlo; Lacedelli, Gaia; Lam, Kristine; Laskar, Jacques; Latham, David W.; Lecavelier des Etangs, Alain; Lendl, Monika; Lester, Kathryn V.; Levine, Alan M.; Livingston, John; Lovis, Christophe; Luque, Rafael; Magrin, Demetrio; Marie-Sainte, Wenceslas; Maxted, Pierre F. L.; Mayo, Andrew W.; McLean, Brian; Mecina, Marko; Mékarnia, Djamel; Nascimbeni, Valerio; Nielsen, Louise D.; Olofsson, Göran; Osborn, Hugh P.; Osborne, Hannah L. M.; Ottensamer, Roland; Pagano, Isabella; Pallé, Enric; Peter, Gisbert; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Ragazzoni, Roberto; Rando, Nicola; Rauer, Heike; Redfield, Seth; Ribas, Ignasi; Ricker, George R.; Rieder, Martin; Santos, Nuno C.; Scandariato, Gaetano; Schmider, François-Xavier; Schwarz, Richard P.; Scott, Nicholas J.; Seager, Sara; Ségransan, Damien; Serrano, Luisa Maria; Simon, Attila E.; Smith, Alexis M. S.; Steller, Manfred; Stockdale, Chris; Szabó, Gyula; Thomas, Nicolas; Ting, Eric B.; Triaud, Amaury H. M. J.; Udry, Stéphane; Van Eylen, Vincent; Van Grootel, Valérie; Vanderspek, Roland K.; Viotto, Valentina; Walton, Nicholas; Winn, Joshua N., We report the discovery and characterization of a pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 (TIC 79748331), initially detected in the Transiting Exoplanet Survey Satellite (TESS) photometry. To characterize the system, we performed and retrieved the CHaracterising ExOPlanets Satellite (CHEOPS), TESS, and ground-based photometry, the High Accuracy Radial velocity Planet Searcher (HARPS) high-resolution spectroscopy, and Gemini speckle imaging. We characterize the host star and determine Teff,⋆=4734±67K⁠, R⋆=0.726±0.007R⊙⁠, and M⋆=0.748±0.032M⊙⁠. We present a novel detrending method based on point spread function shape-change modelling and demonstrate its suitability to correct flux variations in CHEOPS data. We confirm the planetary nature of both bodies and find that TOI-1064 b has an orbital period of Pb = 6.44387 ± 0.00003 d, a radius of Rb = 2.59 ± 0.04 R⊕, and a mass of Mb=13.5+1.7−1.8 M⊕, whilst TOI-1064 c has an orbital period of Pc=12.22657+0.00005−0.00004 d, a radius of Rc = 2.65 ± 0.04 R⊕, and a 3σ upper mass limit of 8.5 M⊕. From the high-precision photometry we obtain radius uncertainties of ∼1.6 per cent, allowing us to conduct internal structure and atmospheric escape modelling. TOI-1064 b is one of the densest, well-characterized sub-Neptunes, with a tenuous atmosphere that can be explained by the loss of a primordial envelope following migration through the protoplanetary disc. It is likely that TOI-1064 c has an extended atmosphere due to the tentative low density, however further radial velocities are needed to confirm this scenario and the similar radii, different masses nature of this system. The high-precision data and modelling of TOI-1064 b are important for planets in this region of mass–radius space, and it allow us to identify a trend in bulk density–stellar metallicity for massive sub-Neptunes that may hint at the formation of this population of planets. © The Author(s) 2022., This study is based on observations made with ESO Telescopes at the La Silla Observatory under program ID 1102.C-0923. CHEOPS is an ESA mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden, and the UK. The CHEOPS Consortium would like to gratefully acknowledge the support received by all the agencies, offices, universities, and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission. Funding for the TESS mission is provided by NASA Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. Part of this work was done using data taken by KESPRINT, an international consortium devoted to the characterization and research of exoplanets discovered with space-based missions (http://www.kesprint.science/). This work makes use of observations from the LCOGT network. Part of the LCOGT telescope time was granted by NOIRLab through the Mid-Scale Innovations Program (MSIP). MSIP is funded by NSF. This study is based on data collected under the NGTS project at the ESO La Silla Paranal Observatory. The NGTS facility is operated by the consortium institutes with support from the UK Science and Technology Facilities Council (STFC) projects ST/M001962/1 and ST/S002642/1. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This work makes use of observations from the ASTEP telescope. ASTEP benefited from the support of the French and Italian polar agencies IPEV and PNRA in the framework of the Concordia station program and from Idex UCAJEDI (ANR-15-IDEX-01). Some of the observations in the paper made use of the High-Resolution Imaging instrument Zorro. Zorro was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. Zorro was mounted on the Gemini-South telescope of the international Gemini Observatory, a program of NSF’s OIR Lab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (USA), National Research Council Canada (Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio de Ciencia, Tecnología e Innovación (Argentina), Ministério da Ciência, Tecnologia, Inovações e Comunicações (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). TGW, ACC, and KH acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant ST/R003203/1. YA and MJH acknowledge the support of the Swiss National Fund under grant 200020_172746. DG and LMS gratefully acknowledge financial support from the CRT Foundation under grant no. 2018.2323 ‘Gaseous or rocky? Unveiling the nature of small worlds’. DG, MF, XB, SC, and JL acknowledge their roles as ESA-appointed CHEOPS science team members. CMP, MF, JK, and AJM gratefully acknowledge the support of the Swedish National Space Agency (SNSA; DNR 65/19, 174/18, 2020-00104, and Career grant 120/19C). ADe and DE acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2020 Framework Programme (project fOURaCES; grant agreement no. 724427). ADe, ALe, and HO acknowledge support from the Swiss National Centre for Competence in Research ‘PlanetS’ and the Swiss National Science Foundation (SNSF). SH gratefully acknowledges CNES funding through the grant 837319. SES have received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Framework Programme (grant agreement no. 833925, project STAREX). SGS acknowledges support from FCT through FCT contract no. CEECIND/00826/2018 and POPH/FSE (EC). We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016-80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017-87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de Maeztu-Centro de Astrobiología (INTA-CSIC), and the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract no. 4000124370. SCCB and VA acknowledge support from FCT through FCT contracts no. IF/01312/2014/CP1215/CT0004 and IF/00650/2015/CP1273/CT0001, respectively. ABr was supported by the SNSA. This project was supported by the CNES. LD is an F.R.S.-FNRS Postdoctoral Researcher. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. This work was supported by FCT – Fundação para a Ciência e a Tecnologia – through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 & POCI-01-0145-FEDER-032113, PTDC/FIS-AST/28953/2017 & POCI-01-0145-FEDER-028953, PTDC/FIS-AST/28987/2017, and POCI-01-0145-FEDER-028987, ODSD is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. B-OD acknowledges support from the Swiss National Science Foundation (PP00P2-190080). DD acknowledges support from the TESS Guest Investigator Program grant 80NSSC19K1727 and NASA Exoplanet Research Program grant 18-2XRP18_2-0136. MG is an F.R.S.-FNRS Senior Research Associate. KGI is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. GL acknowledges support by CARIPARO Foundation, according to the agreement CARIPARO-Universitá degli Studi di Padova (Pratica no. 2018/0098). This work was granted access to the HPC resources of MesoPSL financed by the Region Ile de France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche. ML acknowledges support from the Swiss National Science Foundation under grant no. PCEFP2_194576. PFLM acknowledges support from STFC research grant number ST/M001040/1. LDN thanks the Swiss National Science Foundation for support under Early Postdoc. Mobility grant P2GEP2_200044. This work was also partially supported by a grant from the Simons Foundation (PI: Queloz, grant number 327127). IR acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya/CERCA programme. This project has been supported by the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, the MTA-ELTE Lendület Milky Way Research Group, and the City of Szombathely under agreement no. 67.177-21/2016. This research received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Framework Programme (grant agreement no. 803193/BEBOP), and from the Science and Technology Facilities Council (STFC; grant no. ST/S00193X/1). VVG is an F.R.S-FNRS Research Associate., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

The Next Generation Transit Survey (NGTS) is a state-of-the-art photometric facility located at ESO’s Paranal Observatory. NGTS is able to reach a precision of 150 ppm in 30 minutes, making it the most precise ground-based photometric system in the world. This precision has led to the discovery of a rare exoplanet in the “Neptune Desert” (NGTS-4b), the shortest-period hot Jupiter ever discovered (NGTS-10b), and the first exoplanet recovered from a TESS monotransit candidate (NGTS-11b). It has also allowed NGTS to characterise exoplanet candidates transiting very bright stars (V < 10) from the TESS mission, and to make coordinated observations in support of VLT programmes., Published in The Messenger vol. 181, pp. 28-32, September 2020.

Context. Planetary population analysis gives us insight into formation and evolution processes. For short-period planets, the sub-Jovian desert has been discussed in recent years with regard to the planet population in the mass/period and radius/period parameter space without taking stellar parameters into account. The Next Generation Transit Survey (NGTS) is optimised for detecting planets in this regime, which allows for further analysis of the sub-Jovian desert. Aims. With high-precision photometric surveys (e.g. with NGTS and TESS), which aim to detect short period planets especially around M/K-type host stars, stellar parameters need to be accounted for when empirical data are compared to model predictions. Presenting a newly discovered planet at the boundary of the sub-Jovian desert, we analyse its bulk properties and use it to show the properties of exoplanets that border the sub-Jovian desert. Methods. Using NGTS light curve and spectroscopic follow-up observations, we confirm the planetary nature of planet NGTS-5b and determine its mass. Using exoplanet archives, we set the planet in context with other discoveries. Results. NGTS-5b is a short-period planet with an orbital period of 3.3569866 +/- 0.0000026 days. With a mass of 0.229 +/- 0.037 M-Jup and a radius of 1.136 +/- 0.023 R-Jup, it is highly inflated. Its mass places it at the upper boundary of the sub-Jovian desert. Because the host is a K2 dwarf, we need to account for the stellar parameters when NGTS-5b is analysed with regard to planet populations. Conclusions. With red-sensitive surveys (e.g. with NGTS and TESS), we expect many more planets around late-type stars to be detected. An empirical analysis of the sub-Jovian desert should therefore take stellar parameters into account.