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We report the discovery of TOI-530b, a transiting giant planet around an M0.5V dwarf, delivered by the Transiting Exoplanet Survey Satellite (TESS). The host star is located at a distance of $147.7\pm0.6$ pc with a radius of $R_{\ast}=0.54\pm0.03\ R_{\odot}$ and a mass of $M_{\ast}=0.53\pm0.02\ M_{\odot}$. We verify the planetary nature of the transit signals by combining ground-based multi-wavelength photometry, high resolution spectroscopy from SPIRou as well as high-angular-resolution imaging. With $V=15.4$ mag, TOI-530b is orbiting one of the faintest stars accessible by ground-based spectroscopy. Our model reveals that TOI-530b has a radius of $0.83\pm0.05\ R_{J}$ and a mass of $0.4\pm0.1\ M_{J}$ on a 6.39-d orbit. TOI-530b is the sixth transiting giant planet hosted by an M-type star, which is predicted to be infrequent according to core accretion theory, making it a valuable object to further study the formation and migration history of similar planets. We discuss the potential formation channel of such systems., Comment: 17 pages, 12 figures, 8 tables, accepted for publication by MNRAS

The composition of several exoplanet atmospheres has been largely debated with contrasting results in the literature. Low- and high-resolution spectroscopy offer complementary views, although sometimes appear to be in sparkling contrast. We present a new approach to simultaneously model low- and high-resolution observation and apply this method to resolve known controversies in the literature. We show that the synergy between different techniques of observations is significantly more informative than the separate analyses. We recommend the joint analysis of low- and high-resolution exoplanet spectra to fully exploit the potential of upcoming space missions, such as JWST, Twinkle and Ariel.

We present the discovery and validation of a temperate sub-Neptune around the nearby mid-M dwarf TIC 470381900 (TOI-1696), with a radius of $3.09 \pm 0.11 \,R_\oplus$ and an orbital period of $2.5 \,\rm{days}$, using a combination of TESS and follow-up observations using ground-based telescopes. Joint analysis of multi-band photometry from TESS, MuSCAT, MuSCAT3, Sinistro, and KeplerCam confirmed the transit signal to be achromatic as well as refined the orbital ephemeris. High-resolution imaging with Gemini/'Alopeke and high-resolution spectroscopy with the Subaru/IRD confirmed that there are no stellar companions or background sources to the star. The spectroscopic observations with IRD and IRTF/SpeX were used to determine the stellar parameters, and found the host star is an M4 dwarf with an effective temperature of $T_{eff} = 3185 \pm 76\,\rm{K}$ and a metallicity of [Fe/H] $=0.336 \pm 0.060 \,\rm{dex}$. The radial velocities measured from IRD set a $2$-$\sigma$ upper limit on the planetary mass to be $48.8 \,M_\oplus$. The large radius ratio ($R_p/R_\star \sim 0.1$) and the relatively bright NIR magnitude ($J=12.2 \,\rm{mag}$) make this planet an attractive target for further followup observations. TOI-1696b is one of the planets belonging to the Neptunian desert with the highest transmission spectroscopy metric discovered to date, making it an interesting candidate for atmospheric characterizations with JWST., Comment: 25 pages, 18 figures, 3 tables, Submitted to AJ

Full list of authors: Christian, Sam; Vanderburg, Andrew; Becker, Juliette; Yahalomi, Daniel A.; Pearce, Logan; Zhou, George ; Collins, Karen A.; Kraus, Adam L.; Stassun, Keivan G.; de Beurs, Zoe; Ricker, George R.; Vanderspek, Roland K.; Latham, David W.; Winn, Joshua N.; Seager, S.; Jenkins, Jon M.; Abe, Lyu; Agabi, Karim; Amado, Pedro J.; Baker, David; Barkaoui, Khalid; Benkhaldoun, Zouhair; Benni, Paul; Berberian, John; Berlind, Perry; Bieryla, Allyson; Esparza-Borges, Emma; Bowen, Michael; Brown, Peyton; Buchhave, Lars A.; Burke, Christopher J.; Buttu, Marco; Cadieux, Charles; Caldwell, Douglas A.; Charbonneau, David; Chazov, Nikita; Chimaladinne, Sudhish; Collins, Kevin I.; Combs, Deven; Conti, Dennis M.; Crouzet, Nicolas; de Leon, Jerome P.; Deljookorani, Shila; Diamond, Brendan; Doyon, René; Dragomir, Diana; Dransfield, Georgina; Essack, Zahra; Evans, Phil; Fukui, Akihiko; Gan, Tianjun; Esquerdo, Gilbert A.; Gillon, Michaël; Girardin, Eric; Guerra, Pere; Guillot, Tristan; K. Habich, Eleanor Kate; Henriksen, Andreea; Hoch, Nora; Isogai, Keisuke I.; Jehin, Emmanuël; Jensen, Eric L. N.; Johnson, Marshall C.; Livingston, John H.; Kielkopf, John F.; Kim, Kingsley; Kawauchi, Kiyoe; Krushinsky, Vadim; Kunzle, Veronica; Laloum, Didier; Leger, Dominic; Lewin, Pablo; Mallia, Franco; Massey, Bob; Mori, Mayuko; McLeod, Kim K.; Mékarnia, Djamel; Mireles, Ismael; Mishevskiy, Nikolay; Tamura, Motohide; Murgas, Felipe; Narita, Norio; Naves, Ramon; Nelson, Peter; Osborn, Hugh P.; Palle, Enric; Parviainen, Hannu; Plavchan, Peter; Pozuelos, Francisco J.; Rabus, Markus; Relles, Howard M.; Rodríguez López, Cristina; Quinn, Samuel N.; Schmider, Francois-Xavier; Schlieder, Joshua E.; Schwarz, Richard P.; Shporer, Avi; Sibbald, Laurie; Srdoc, Gregor; Stibbards, Caitlin; Stickler, Hannah; Suarez, Olga; Stockdale, Chris; Tan, Thiam-Guan; Terada, Yuka; Triaud, Amaury; Tronsgaard, Rene; Waalkes, William C.; Wang, Gavin; Watanabe, Noriharu; Wenceslas, Marie-Sainte; Wingham, Geof; Wittrock, Justin; 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., Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. We determine that there is statistically significant difference in the inclination distribution of wide-binary systems with transiting planets compared to a control sample, with the probability that the two distributions are the same being 0.0037. This implies that there is an overabundance of planets in binary systems whose orbits are aligned with those of the binary. The overabundance of aligned systems appears to primarily have semimajor axes less than 700 au. We investigate some effects that could cause the alignment and conclude that a torque caused by a misaligned binary companion on the protoplanetary disk is the most promising explanation. © 2022. The Author(s). Published by the American Astronomical Society., The IRSF project is a collaboration between Nagoya University and the South African Astronomical Observatory (SAAO) supported by the Grants-in-Aid for Scientific Research on Priority Areas (A) (grant Nos. 10147207 and 10147214) and Optical & Near-Infrared Astronomy Inter-University Cooperation Program, from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan and the National Research Foundation (NRF) of South Africa. This work is partly supported by JSPS KAKENHI grant No. JP18H05439, and JST PRESTO grant No. JPMJPR1775, and a University Research Support Grant from the National Astronomical Observatory of Japan (NAOJ). This work is partly supported by Grant-in-Aid for JSPS Fellows, grant No. JP20J21872. This work is partly supported by JSPS KAKENHI grant No. JP17H04574. This work is partly supported by JSPS KAKENHI grant No. JP20K14518, and by Astrobiology Center SATELLITE Research project AB022006. M.T. is supported by MEXT/JSPS KAKENHI grant Nos. 18H05442, 15H02063, and 22000005. This work is partly supported by JSPS KAKENHI grant No. JP21K13955. This work is partly supported by JSPS KAKENHI grant No. 20K14521. C.R.-L. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709). M.R. acknowledges support from the Universidad Católica de lo Santísima Concepción grant DI-FIAI 03/2021. P.J.A. acknowledges support from grant AYA2016-79425-C3-3-P of the Spanish Ministry of Economy and Competitiveness (MINECO) and the Centre of Excellence "Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). This paper is based on observations made with the T150 telescope at the Sierra Nevada Observatory (Granada, Spain), operated by the Instituto de Astrofísica de Andalucía (IAA—CSIC). 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 FRFC 2.5.594.09.F. TRAPPIST-North is a project funded by the University of Liège (Belgium), in collaboration with Cadi Ayyad University of Marrakech (Morocco). D.D. acknowledges support from the TESS Guest Investigator Program grant No. 80NSSC19K1727 and NASA Exoplanet Research Program grant No. 18-2XRP18_2-0136. M.G. and E.J. are F.R.S.-FNRS Senior Research Associates. K.K.M. acknowledges support from the New York Community Trust's Fund for Astrophysical Research. This work has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation.

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.--Full lis of authors: Fukui, Akihiko; Kimura, Tadahiro; Hirano, Teruyuki; Narita, Norio; Kodama, Takanori; Hori, Yasunori; Ikoma, Masahiro; Palle, Enric; Murgas, Felipe; Parviainen, Hannu; Kawauchi, Kiyoe; Mori, Mayuko; Esparza-Borges, Emma; Bieryla, Allyson; Irwin, Jonathan; Safonov, Boris S.; Stassun, Keivan G.; Alvarez-Hernandez, Leticia; Bejar, Victor J. S.; Casasayas-Barris, Nuria; Chen, Guo; Crouzet, Nicolas; de Leon, Jerome P.; Isogai, Keisuke; Kagetani, Taiki; Klagyivik, Peter; Korth, Judith; Kurita, Seiya; Kusakabe, Nobuhiko; Livingston, John; Luque, Rafael; Madrigal-Aguado, Alberto; Morello, Giuseppe; Nishiumi, Taku; Orell-Miquel, Jaume; Oshagh, Mahmoudreza; Sanchez-Benavente, Manuel; Stangret, Monika; Terada, Yuka; Watanabe, Noriharu; Zou, Yujie; Tamura, Motohide; Kurokawa, Takashi; Kuzuhara, Masayuki; Nishikawa, Jun; Omiya, Masashi; Vievard, Sebastien; Ueda, Akitoshi; Latham, David W.; Quinn, Samuel N.; Strakhov, Ivan S.; Belinski, Alexandr A.; Jenkins, Jon M.; Ricker, George R.; Seager, Sara; Vanderspek, Roland; Winn, Joshua N.; Charbonneau, David; Ciardi, David R.; Collins, Karen A.; Doty, John P.; Bachelet, Etienne; Harbeck, Daniel., We report the discovery of TOI-2285b, a sub-Neptune-sized planet transiting a nearby (42 pc) M dwarf with a period of 27.3 d. We identified the transit signal from the Transiting Exoplanet Survey Satellite photometric data, which we confirmed with ground-based photometric observations using the multiband imagers MuSCAT2 and MuSCAT3. Combining these data with other follow-up observations including high-resolution spectroscopy with the Tillinghast Reflector Echelle Spectrograph, high-resolution imaging with the SPeckle Polarimeter, and radial velocity (RV) measurements with the InfraRed Doppler instrument, we find that the planet has a radius of 1.74±0.08R⊕⁠, a mass of, Funding for the TESS mission is provided by NASA’s Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS SPOC. 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. This paper includes data that are publicly available from the MAST. 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 NASA under the Exoplanet Exploration Program. This work makes use of observations from the LCO global telescope network. This paper is based on observations made with the MuSCAT3 instrument, developed by the Astrobiology Center (ABC) and under financial supports by JSPS KAKENHI (JP18H05439) and JST PRESTO (JPMJPR1775), at FTN on Maui, HI, operated by the LCO, and observations made with the MuSCAT2 instrument, developed by ABC, at TCS operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide. This paper is partially based on observations made at the CMO SAI MSU with the support by M.V. Lomonosov Moscow State University Program of Development. This work is partly supported by JSPS KAKENHI Grant Numbers 22000005, JP15H02063, JP17H04574, JP18H05439, JP18H05442, JP20K14518, Grant-in-Aid for JSPS Fellows Grant Number JP20J21872, JST PRESTO Grant Number JPMJPR1775, and the ABC of National Institutes of Natural Sciences (Grant Number AB031010). This work is partly financed by the Spanish Ministry of Economics and Competitiveness through grants PGC2018-098153-B-C31 and PID2019-109522GB-C53. A.A.B., B.S.S., and I.A.S. acknowledge the support of Ministry of Science and Higher Education of the Russian Federation under the grant 075-15-2020-780 (N13.1902.21.0039). N.C.B. and G.M. acknowledge the funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program under grant agreement No. 694513 and under the Marie Skłodowska-Curie grant agreement No. 895525, respectively. J.K. acknowledges the support of the Swedish National Space Agency (SNSA; DNR 2020-00104). R.L. acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación, through project PID2019-109522GB-C52/AEI/10.13039/501100011033, and the Centre of Excellence “Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709).

We report the discovery of an eccentric hot Neptune and a non-transiting outer planet around TOI-1272. We identified the eccentricity of the inner planet, with an orbital period of 3.3 d and $R_{\rm p,b} = 4.1 \pm 0.2$ $R_\oplus$, based on a mismatch between the observed transit duration and the expected duration for a circular orbit. Using ground-based radial velocity measurements from the HIRES instrument at the Keck Observatory, we measured the mass of TOI-1272b to be $M_{\rm p,b} = 25 \pm 2$ $M_\oplus$. We also confirmed a high eccentricity of $e_b = 0.34 \pm 0.06$, placing TOI-1272b among the most eccentric well-characterized sub-Jovians. We used these RV measurements to also identify a non-transiting outer companion on an 8.7-d orbit with a similar mass of $M_{\rm p,c}$ sin$i= 27 \pm 3$ $M_\oplus$ and $e_c \lesssim 0.35$. Dynamically stable planet-planet interactions have likely allowed TOI-1272b to avoid tidal eccentricity decay despite the short circularization timescale expected for a close-in eccentric Neptune. TOI-1272b also maintains an envelope mass fraction of $f_{\rm env} \approx 11\%$ despite its high equilibrium temperature, implying that it may currently be undergoing photoevaporation. This planet joins a small population of short-period Neptune-like planets within the "Hot Neptune Desert" with a poorly understood formation pathway., Comment: Accepted at The Astronomical Journal; 17 pages, 11 figures

WASP-33b, a hot Jupiter around a hot star, is a rare system in which nodal precession has been discovered. We updated the model for the nodal precession of WASP-33b by adding new observational points. Consequently, we found a motion of the nodal precession spanning 11 yr. We present homogenous Doppler tomographic analyses of eight data sets, including two new data sets from TS23 and HIDES, obtained between 2008 and 2019, to illustrate the variations in the projected spin–orbit obliquity of WASP-33b and its impact parameter. We also present its impact parameters based on photometric transit observations captured by MuSCAT in 2017 and MuSCAT2 in 2018. We derived its real spin–orbit obliquity ψ, stellar spin inclination is, and stellar gravitational quadrupole moment J2 from the time variation models of the two orbital parameters. We obtained $\psi = 108.19^{+0.95}_{-0.97}$ deg, $i_\mathit{ s} = 58.3^{+4.6}_{-4.2}$ deg, and $J_2=(1.36^{+0.15}_{-0.12}) \times 10^{-4}$. Our J2 value was slightly smaller than the theoretically predicted value, which may indicate that its actual stellar internal structure is different from the theoretical one. We derived the nodal precession speed $\dot{\theta }=0.507^{+0.025}_{-0.022}$ deg yr−1, and its period $P_{\mathrm{pre}}=709^{+33}_{-34}$ yr, and found that WASP-33b transits in front of WASP-33 for only ∼ 20 per cent of the entire nodal precession period.

Current theories of planetary evolution predict that infant giant planets have large radii and very low densities before they slowly contract to reach their final size after about several hundred million years 1, 2. These theoretical expectations remain untested to date, despite the increasing number of exoplanetary discoveries, as the detection and characterisation of very young planets is extremely challenging due to the intense stellar activity of their host stars 3, 4. However, the recent discoveries of young planetary transiting systems allow to place initial constraints on evolutionary models5–9. With an estimated age of 20 million years, V1298 Tau is one of the youngest solar-type stars known to host transiting planets: it harbours a multiple system composed of two Neptune-sized, one Saturn-sized, and one Jupiter-sized planets 10, 11. Here we report the dynamical masses of two of the four planets. We find that planet b, with an orbital period of 24 days, has a mass of 0.60 Jupiter masses and a density similar to the giant planets of the Solar System and other known giant exoplanets with significantly older ages 12, 13. Planet e, with an orbital period of 40 days, has a mass of 1.21 Jupiter masses and a density larger than most giant exoplanets. This is unexpected for planets at such a young age and suggests that some giant planets might evolve and contract faster than anticipated, thus challenging current models of planetary evolution.

Space-based transit missions such as Kepler and TESS have demonstrated that planets are ubiquitous. However, the success of these missions heavily depends on ground-based radial velocity (RV) surveys, which combined with transit photometry can yield bulk densities and orbital properties. While most Kepler host stars are too faint for detailed follow-up observations, TESS is detecting planets orbiting nearby bright stars that are more amenable to RV characterization. Here we introduce the TESS-Keck Survey (TKS), an RV program using ~100 nights on Keck/HIRES to study exoplanets identified by TESS. The primary survey aims are investigating the link between stellar properties and the compositions of small planets; studying how the diversity of system architectures depends on dynamical configurations or planet multiplicity; identifying prime candidates for atmospheric studies with JWST; and understanding the role of stellar evolution in shaping planetary systems. We present a fully-automated target selection algorithm, which yielded 103 planets in 86 systems for the final TKS sample. Most TKS hosts are inactive, solar-like, main-sequence stars (4500 K < Teff < 6000 K) at a wide range of metallicities. The selected TKS sample contains 71 small planets (Rp < 4 Re), 11 systems with multiple transiting candidates, 6 sub-day period planets and 3 planets that are in or near the habitable zone of their host star. The target selection described here will facilitate the comparison of measured planet masses, densities, and eccentricities to predictions from planet population models. Our target selection software is publicly available (at https://github.com/ashleychontos/sort-a-survey) and can be adapted for any survey which requires a balance of multiple science interests within a given telescope allocation., 23 pages, 10 figures, 5 tables

Multi-band photometric transit observations or low resolution spectroscopy (spectro-photometry) are normally used to retrieve the broadband transmission spectra of transiting exoplanets in order to assess the chemical composition of their atmospheres. In this work, we present an alternative approach for recovering the broadband transmission spectra using chromatic Doppler Tomography. To validate the method and examine its performance, we used new observational data obtained with the ESPRESSO instruments to retrieve the transmission spectra of the archetypal hot Jupiter HD209458b. Our findings indicate that the recovered transmission spectrum is in good agreement with the results presented in previous studies, which used different methodologies to extract the spectrum.

We present the discovery of a highly irradiated and moderately inflated ultra-hot Jupiter, TOI-1431b/MASCARA-5b (HD 201033b), first detected by NASA's Transiting Exoplanet Survey Satellite mission (TESS) and the Multi-site All-Sky CAmeRA (MASCARA). The signal was established to be of planetary origin through radial velocity measurements obtained using SONG, SOPHIE, FIES, NRES, and EXPRES, which show a reflex motion of $K=294.1\pm1.1$ m s$^{-1}$. A joint analysis of the TESS and ground-based photometry and radial velocity measurements reveals that TOI-1431b has a mass of $M_{p}=3.12\pm0.18$ $\rm{M_J}$ ($990\pm60$ M$_{\oplus}$), an inflated radius of $R_{p}=1.49\pm0.05$ $\rm{R_J}$ ($16.7\pm0.6$ R$_{\oplus}$), and an orbital period of $P=2.650237\pm0.000003$ d. Analysis of the spectral energy distribution of the host star reveals that the planet orbits a bright ($\mathrm{V}=8.049$ mag) and young ($0.29^{+0.32}_{-0.19}$ Gyr) Am type star with $T_{\rm eff}=7690^{+400}_{-250}$ $\rm{K}$, resulting in a highly irradiated planet with an incident flux of $\langle F \rangle=7.24^{+0.68}_{-0.64}\times$10$^9$ erg s$^{-1}$ cm$^{-2}$ ($5300^{+500}_{-470}\mathrm{S_{\oplus}}$) and an equilibrium temperature of $T_{eq}=2370\pm70$ K. TESS photometry also reveals a secondary eclipse with a depth of $127^{+4}_{-5}$ppm as well as the full phase curve of the planet's thermal emission in the red-optical. This has allowed us to measure the dayside and nightside temperature of its atmosphere as $T_\mathrm{day}=3004\pm64$ K and $T_\mathrm{night}=2583\pm63$ K, the second hottest measured nightside temperature. The planet's low day/night temperature contrast ($\sim$420 K) suggests very efficient heat transport between the dayside and nightside hemispheres., Accepted for publication in the Astronomical Journal. 39 pages, 18 figures, and 4 tables