Context. Hot and warm Jupiters might have undergone the same formation and evolution path but the two populations exhibit different distributions of orbital parameters. This challenges our understanding of their actual origin. Aims. We report the results of our warm Jupiters survey which was carried out with the CHIRON spectrograph within the KESPRINT collaboration. We addressed the question of the population origin by studying two planets that might help to bridge the gap between the two populations. Methods. We confirm two planets and determine their mass. One is a hot Jupiter with an orbital period shorter than 10 days TOI2420 b and the other is a warm Jupiter TOI2485 b. We analyzed them using a wide variety of spectral and photometric data in order to characterize these planetary systems. Results. We found that TOI2420 b has an orbital period of PSUBbSUB5.8 days a mass of MSUBbSUB0.9 MSUBJSUB and a radius of RSUBbSUB1.3 RSUBJSUB with a planetary density of 0.477 g cmSUP3SUP. TOI2485 b has an orbital period of PSUBbSUB11.2 days a mass of MSUBbSUB2.4 MSUBJSUB and a radius of RSUBbSUB1.1 RSUBJSUB with a density of 2.36 g cmSUP3SUP. Conclusions. With the current parameters the migration history for TOI2420 b and TOI2485 b is unclear Scenarios of a higheccentricity migration cannot be ruled out and the characteristics of TOI2485 b even support this scenario.
['planets and satellites: detection', 'planets and satellites: gaseous planets', 'Astrophysics - Earth and Planetary Astrophysics']
Mass determination of two Jupitersized planets orbiting slightly evolved stars TOI2420 b and TOI2485 b
{'Mass determination of two Jupiter-sized planets orbiting slightly evolved stars: TOI-2420 b and TOI-2485 b': 'Ilaria Carleo 1 , 2 , 3 , Oscar Barrágan 4 , Carina M. Persson 5 , Malcolm Fridlund 5 , 6 , Kristine W. F. Lam 7 , Sergio Messina 8 , Davide Gandolfi 9 , Alexis M. S. Smith 7 , Marshall C. Johnson 10 , William Cochran 17 , Hannah L. M. Osborne 11 , 12 , Rafael Brahm 13 , 14 , David R. Ciardi 15 , Karen A. Collins 16 , Mark E. Everett 18 , Steven Giacalone 19 , Eike W. Guenther 20 , Artie Hatzes 20 , Coel Hellier 21 , Jonathan Horner 26 Petr Kabáth 22 , Judith Korth 23 , Phillip MacQueen 17 , Thomas Masseron 2 , 3 , Felipe Murgas 2 , 3 , Grzegorz Nowak 24 , 2 , 3 , Joseph E. Rodriguez 25 , Cristilyn N. Watkins 16 , Rob Wittenmyer 26 , George Zhou 26 , Carl Ziegler 27 , Allyson Bieryla 16 , Patricia T. Boyd 28 , Catherine A. Clark 29 , 15 , Courtney D. Dressing 30 , Jason D. Eastman 16 Jan Eberhardt 31 , Michael Endl 17 , Nestor Espinoza 32 , Michael Fausnaugh 33 , 34 , Natalia M. Guerrero 34 , 35 , Thomas Henning 31 , Katharine Hesse 34 , Melissa J. Hobson 36 , Steve B. Howell 37 , Andrés Jordán 13 , 14 , David W. Latham 16 , Michael B. Lund 15 , Ismael Mireles 38 , Norio Narita 39 , 40 , 2 , Marcelo Tala Pinto 13 , 14 , Teznie Pugh 17 , Samuel N. Quinn 16 , George Ricker 34 , David R. Rodriguez 32 Felipe I. Rojas 41 , 14 , Mark E. Rose 37 , Alexander Rudat 34 , Paula Sarkis 31 , Arjun B. Savel 42 , Martin Schlecker 43 , Richard P. Schwarz 16 , Sara Seager 34 , 44 , 45 , Avi Shporer 34 , Je ff rey C. Smith 46 , Keivan G. Stassun 47 , Chris Stockdale 48 , Trifon Trifonov 31 , 49 , 50 , Roland Vanderspek 34 , Joshua N. Winn 52 26  \nand Duncan Wright  \n(A ffi liations can be found after the references)  \nReceived Date Month YYYY; accepted Date Month YYYY', 'ABSTRACT': "Context. Hot and warm Jupiters might have undergone the same formation and evolution path, but the two populations exhibit di ff erent distributions of orbital parameters, challenging our understanding on their actual origin.  \nAims. The present work, which is the results of our warm Jupiters survey carried out with the CHIRON spectrograph within the KESPRINT collaboration, aims to address this challenge by studying two planets that could help bridge the gap between the two populations.  \nMethods. Wereport the confirmation and mass determination of a hot Jupiter (orbital period shorter than 10 days), TOI-2420 b, and a warm Jupiter, TOI-2485 b. We performed a joint analysis using a wide variety of spectral and photometric data in order to characterize these planetary systems. Results. We found that TOI-2420 b has an orbital period of Pb = 5.8 days, a mass of Mb = 0.9 MJ and a radius of Rb = 1.3 RJ, with a planetary density of 0.477 g cm -3 ; while TOI-2485 b has an orbital period of Pb = 11.2 days, a mass of Mb = 2.4 MJ and a radius of Rb = 1.1 RJ with density 2.36 g cm -3 .  \nConclusions. With current parameters, the migration history for TOI-2420 b and TOI-2485 b is unclear: the high-eccentricity migration scenarios cannot be ruled out, and TOI-2485 b's characteristics may rather support this scenario.", '1. Introduction': "Almost 30 years since the discovery of the first hot Jupiter (HJ), 51 Peg b (Mayor & Queloz 1995), the formation and migration history of close-in giant planets is still debated. The orbit of 51 Peg b proved a huge surprise to astronomers at the time (see e.g. Guillot et al. 1996, who state that the newly discovered planet 'is surely the most problematic find in recent memory'). A planet comparable in mass to Jupiter moving on an orbit extremely close to its host star ran counter to the prevailing understanding of planet formation at the time, which was based solely on our knowledge of the Solar system 1 .  \n51 Peg b was the first of a population of planets that quickly became known as the 'hot Jupiters' (HJs) (e.g. Schilling 1996) - giant planets orbiting their host stars with periods less than around ten days . In the years that followed, and more exoplanets were discovered, a number of 'warm Jupiters' (WJs) were  \nalso found - giant planets with orbital periods between 10 and 200 days (e.g., Dawson & Johnson 2018) - again, dramatically di ff erent to the planets in our own Solar system. The origin of both HJs and WJs has been heavily debated.  \nBoth populations could have originated through in-situ formation (Boss 1997), disk migration (Lin & Papaloizou 1986) or high eccentricity migration (Wu & Murray 2003). However, the two populations present di ff erences in some of their properties:  \na) the occurrence rate of WJs per log interval of period is lower than that for HJs (see histogram in Fig. 4 of Dawson & Johnson 2018), but the total occurrence rate of WJs is larger (i.e., Wittenmyer et al. 2010; Zink & Howard 2023);  \nb) most HJs present low eccentricities, while WJs present a wide range of eccentricities (i.e., Correia et al. 2020; Zink & Howard 2023);  \nc) HJs generally lack nearby companions, while WJs have been found with nearby super-Earths (Huang et al. 2016), even though recent studies have demonstrated that a fraction of HJs ⩾ 12 ± 6% have nearby small (1-4 R ⊕ ) companions (Wu et al. 2023) and ∼ 30% of HJs have at least one Warm / Cold Jupiter companion (Zink & Howard 2023).  \nThese di ff erences are likely related to the formation site and migration history of the planets involved. For example, disk migration is thought to be the primary mechanism that produces HJs, but cannot explain the wide eccentricity distribution of WJs. On the other hand, WJs might have experienced higheccentricity tidal migration, but this mechanism is more e ffi cient for closer WJs, since the tidal dissipation has a strong dependence with the semi-major axis. It is thus important to study hot and warm Jupiters and assess the relative e ff ectiveness of the di ff erent formation scenarios proposed for these planets. For a more comprehensive overview of the di ff erent theories on formation and evolution of close-in giant planets, as well as of the similarities and dissimilarities of hot and warm Jupiters see Sec. 4.3 in Dawson & Johnson 2018.  \nIn the past few years, the Transiting Exoplanet Survey Satellite (TESS; Ricker et al. 2014) released thousands of planetary candidates and the exoplanetary community have put substantial e ff ort into the radial velocity (RV) follow-up with ground based spectrographs in order to confirm the planetary nature and determine the mass of the candidates. With this e ff ort, many hot and warm Jupiters have been confirmed (144 in total), allowing us to greatly improve the statistical significance of our sample, and thus improve our understanding of the di ff erence between these two populations.  \nIn this paper, we present the mass determination of two close-in giant planets, one HJ, TOI-2420 b, and one WJ, TOI2485 b. We present the observations of the two targets, including TESS photometry, ground-based photometry, and spectroscopy in Section 2, the stellar characterization in Section 3, the planetary systems' modelling with the transit and RV joint fit in analysis of the photometry together with the transit fit and RV modeling in Section 4. Finally, we discuss our results and present our conclusions in Section 5.", '2.1. TESS photometry': 'TOI-2420 (TIC 268532343) was observed by TESS between 2018 September 20 and 2019 January 24 in sector 3 on CCD1 of Camera 1, as well as between 2020 September 23 and 2020 November 20 in sector 30 on CCD1 of Camera 1, and was alerted on 2020 November 25. TOI-2485 (TIC 328934463) was observed between 2020 March 19 and 2020 May 04 in sector 23 on CCD4 of Camera 2, and between 2022 March 26 and 2022 May 11 in sector 50 on CCD3 of Camera 2, and alerted on 2021 February 11. The data taken in each sector were observed in 30 min, 10 min, 30 min and 2 min cadence, respectively. The data were reduced by both the MIT Quick-Look Pipeline (QLP; Huang et al. 2020; Kunimoto et al. 2021), and the TESS Science Processing Operations Center (SPOC; Jenkins et al. 2010) pipeline. The SPOC pipeline was adapted from the Kepler mission pipeline at NASA Ames Research Center. The pipeline uses simple aperture photometry (SAP; Twicken et al. 2010) to produce time series light curves. A further presearch data conditioning (PDCSAP) algorithm was subsequently used to correct for common instrumental systematics in the data (Stumpe et al. 2012; Smith et al. 2012). For the sector 50 short cadence data of TOI-2485, we downloaded the SPOC light curve from the Mikulski Archive for Space Telescopes (MAST 2 ). For the other data, we downloaded light curves extracted from the TESS-SPOC pipeline (Caldwell et al. 2020), which followed the  \nsame reduction routines as SPOC but were processed from TESS full frame images.  \nTransit searches and signal assessments were performed by both the SPOC and the QLP pipelines. The light curves were further analysed using the transit search algorithm, DST (Détection Spécialisée de Transits; Cabrera et al. 2012). In QLP and DST pipelines, a transit signal was detected in the TOI2420 data with period P = 5 . 84115 ± 0 . 00257 days, epoch T 0 , BTJD = 1388 . 41352 ± 0 . 00280 (where BTJD is defined as BJD-7000), transit duration T 14 = 4 . 33 ± 0 . 16 h and transit depth d f = 0 . 3023 ± 0 . 0185 %. In the TOI-2485 light curves, a transit signal with P = 11 . 23702 ± 0 . 00654 days, T 0 , BTJD = 1939 . 78211 ± 0 . 00327, T 14 = 6 . 94 ± 0 . 19 h and d f = 0 . 5328 ± 0 . 0231 % was detected.  \nWe iteratively searched for further transit signatures in both datasets after transit signals of the first planet candidates were filtered out. There were no additional transiting candidates detected in both systems. Also no clear periodic variability is found in the TESS light curves.', '2.2. Ground-based Photometry': "The TESS pixel scale is ∼ 21 '' pixel -1 and photometric apertures typically extend out to roughly 1 arcminute, generally causing multiple stars to blend in the TESS photometric aperture. To attempt to determine the true source of the TESS detection, we acquired ground-based time-series follow-up photometry of the fields around TOI-2420 and TOI-2485 as part of the TESS Follow-up Observing Program (TFOP; Collins 2019) 3 . We used the TESS Transit Finder , which is a customized version of the Tapir software package (Jensen 2013), to schedule our transit observations.", '2.2.1. WASP': 'WASP-South (Wide-Angle Search for Planets) was the southern station of the WASP transit-search survey (Pollacco et al. 2006), and consisted of an array of 8 wide-field cameras observing fields with a typical 10-min cadence. The field of TOI-2420 was observed over spans of 160 to 180 nights in each year from 2006 to 2011. In all, 21 150 photometric observations were obtained, using a 48" extraction aperture within which TOI-2420 is the only bright star.  \nWhile TOI-2420b was not a WASP candidate with hindsight we notice that the standard WASP transit-search algorithm finds the 0.3%-deep transit and reports an ephemeris of:  \nTDB(JD) = 245 4432 . 934 ± 0 . 012 + N × 5 . 84265 ± 0 . 00014 .  \nWe also searched the WASP lightcurve for any rotational modulation. We computed the generalised Lomb-Scargle (GLS) periodograms (Zechmeister & Kürster 2009) and estimated the false alarm probability (FAP) via a bootstrap method (Murdoch et al. 1993; Hatzes 2016) that generates 1,000 artificial photometric datasets obtained from the real data, making random permutations in the photometry values. We found the maximum period at ∼ 36 days with a FAP lower than 10 -6 (see Fig. 1).', '2.2.2. LCOGT': "We observed a partial transit window of the planet candidate TOI-2420.01 in Sloan i ' on UTC 2020 December 11 from the  \nFig. 1: GLS periodogram of the WASP-South data for TOI-2420 from 2006 to 2011. There is a possible signal near 40 d, along with aliases from the yearly sampling. The dotted horizontal line is the 1%-likelihood false-alarm level.  \n<!-- image -->  \nLas Cumbres Observatory Global Telescope (LCOGT) (Brown et al. 2013) 1 m network node at Cerro Tololo Inter-American Observatory in Chile (CTIO). We also observed a full transit window in alternating Sloan g ' and Sloan i ' on UTC 2021 September 29 from another LCOGT 1m network node at McDonald Observatory near Fort Davis, Texas, United States (McD). The 1 m telescopes are equipped with a 4096 × 4096 SINISTRO camera having an image scale of 0 '' . 389 per pixel, resulting in a 26 ' × 26 ' field of view and the images were calibrated by the standard LCOGT BANZAI pipeline (McCully et al. 2018), and di ff erential photometric data were extracted using AstroImageJ (Collins et al. 2017). We used circular photometric apertures with radius 7 '' . 0. The target star aperture excluded all of the flux from the nearest known neighbor in the Gaia DR3 catalog ( Gaia DR3 2356241534150962944), which is ∼ 49 '' south of TOI-2420. The light curve data are available on the EXOFOP-TESS website 4 and are included in the global modelling described in section 4.", '2.2.3. KeplerCam': "We observed a partial transit window of the planetary candidate TOI-2485.01 in Sloan i ' on UTC 2021 April 17 from KeplerCam, which is installed on the 1.2 m telescope at the Fred Lawrence Whipple Observatory. The 4096 × 4096 Fairchild CCD 486 detector has an image scale of 0 '' . 672 per 2 × 2 binned pixel, resulting in a 23 ' . 1 × 23 ' . 1 field of view. The images were calibrated and photometric data were extracted with AstroImageJ using a circular aperture with radius 6 '' . 7. The target star aperture excluded all of the flux from the nearest known neighbor in the Gaia DR3 catalog ( Gaia DR3 1443530261849361152), which is ∼ 16 '' north of TOI-2485. The light curve data are available on the EXOFOP-TESS website 5 and are included in the global modelling described in section 4.  \nFig. 2: Periodograms of the RVs data for TOI-2420 (upper panel) and TOI-2485 (lower panel). The dotted horizontal line represent the 0.01% false-alarm level, while the green vertical line is the maximum power, which corresponds to the planetary period.  \n<!-- image -->", '2.3. Ground-based Spectroscopy': 'We collected RVs with di ff erent ground-based instruments. The RVdata described in the following subsections are listed for both targets in Tables A.1 and A.2.', '2.3.1. CHIRON': 'We observed TOI-2420 and TOI-2485 with the spectrograph CHIRON at SMARTS 1.5-meter telescope at Cerro Tololo InterAmerican Observatory, Chile (Tokovinin et al. 2013), within the large observing program (ID: CARL-20B-3081, PI: Carleo) aimed to survey a sample of ∼ 20 warm Jupiters carried out within the KESPRINT collaboration 6 (i.e., de Leon et al. 2021; Smith et al. 2022; Tran et al. 2022; Kabáth et al. 2022; Korth et al. 2023), which aims to confirm and characterize planet candidates from the K2 and TESS space missions. The CHIRON observations were performed in Slicer mode, reaching a spectral resolving power of R = 80 , 000 over the wavelength range of 4100 to 8700 Å. We collected 18 CHIRON spectra for TOI2420 and 14 spectra for TOI-2485. The data reduction was performed through the o ffi cial spectral extraction pipeline of CHIRON Paredes et al. (2021). Radial velocities were obtained via a least-squares deconvolution of the observation against a synthetic non-rotating ATLAS9 model atmosphere spectrum (Castelli & Hubrig 2004). The least-squares deconvolution kernel was modeled via a broadening kernel in order to include the e ff ects of radial velocity shift, rotational, instrumental, and macroturbulent broadening (Zhou et al. 2021). The average RV precision obtained for TOI-2420 is 21 m s -1 and 19 m s -1 for TOI-2485.  \nWe computed the GLS periodograms for both targets (Fig. 2). They exhibit a highly significant periodicity at 5.8 days and 11.2 days, for TOI-2420 and TOI-2485, respectively, which correspond to the planetary signals. The resulting FAP estimated via bootstrap is lower than 10 -6 .', '2.3.2. Minerva-Australis': 'TOI-2420 was observed between 2021 June 5 and 2021 October 4 using the MINERVA-Australis telescope array (Addison et al. 2019), located at Mt. Kent Observatory, Australia. Minerva-Australis is an array of four identical 0.7 m telescopes linked via fiber feeds to a single KiwiSpec echelle spectrograph at a spectral resolving power of R ∼ 80,000 over the wavelength region of 5000-6300Å. The array is wholly dedicated to radialvelocity follow-up of TESS planet candidates (e.g., Nielsen et al. 2019; Addison et al. 2021; Wittenmyer et al. 2022; Rodriguez et al. 2023; Clark et al. 2023). Two simultaneous fibres provide wavelength calibration and correct for instrumental variations. The calibration fibres are illuminated by a quartz lamp through an iodine cell, eliminating contamination by saturated Argon lines. Radial velocities for the observations are derived for each telescope from a least-squares deconvolution against a synthetic non rotating template, similar to the CHIRON pipeline. Each epoch consists of 30-60 minute exposures from up to four individual telescopes. Fibres 3, 4, 5, and 6 obtained 45, 16, 6, and 37 epochs respectively. The radial velocities from each telescope are treated as coming from separate instruments here to account for small velocity o ff sets between the fibres.', '2.3.3. Tull Coudé Spectrometer': 'We observed TOI-2420 with the Tull Coudé Spectrometer (TS23) (Tull et al. 1995) of the McDonald Observatory 2.7m Harlan J. Smith Telescope. TS23 is a cross-dispersed echelle white-pupil spectrograph with a Tektoronix 2048 × 2048 CCD detector. A 1.2 arcsec wide slit gave spectral resolving power R = λ/δλ = 60 , 000. We focus the stellar image onto the slit with a wave-front sensor. This instrumental configuration gives complete spectral coverage from 3400 Å to 5800 Å, and then increasingly large inter-order gaps exist out to 10,800 Å. We insert an I2 gas absorption cell in front of the spectrograph entrance slit in order to impose a stable set of fixed absorption lines on the stellar spectrum before it enters the spectrograph. This enables us to measure precise radial velocity variations of the target star with respect to the I2 lines (cf. Butler et al. 1996). At the start of each night, the spectrograph is automatically re-positioned to within 0.2 pixels of a standard reference position. We obtained 21 separate visits to TOI-2420 between 2021 July 18 and 2022 December 13. We used an exposure meter to terminate each exposure level at a preset signal to noise level. The exposure meter data are then used to compute an accurate flux-weighted barycentric velocity correction for each spectrum. All of the CCD frames were reduced and the echelle spectra were extracted using a script of standard IRAF procedures. We then computed the radial velocities from the extracted spectra using the AUSTRAL code (Endl et al. 2000).', '2.3.4. FEROS': 'TOI-2485 was monitored with the The Fiber-fed Extended Range Optical Spectrograph (Kaufer et al. 1999, FEROS) mounted to the MPG2.2m telescope at the ESO La Silla Observatory, in Chile. FEROS has a spectral resolution of R = 48 , 000 and uses a second fibre to trace instrument induced spectral displacements. The observations of TOI-2485 were obtained in the context of the Warm gIaNts with tEss (WINE) collaboration which focuses on the systematic discovery of transiting warm Jupiters (Brahm et al. 2019; Jordán et al. 2020; Brahm et al. 2020; Schlecker et al. 2020; Hobson et al. 2021; Trifonov et al.  \n2021, 2023; Bozhilov et al. 2023; Brahm et al. 2023; Hobson et al. 2023; Eberhardt et al. 2023; Jones et al. 2024). We obtained 15 FEROS spectra between February of 2021 and July of 2023 using an exposure time of 1200 s obtaining spectra with signalto-noise ratios between 70 and 110 per resolution element depending on the weather and observing conditions. FEROS data were proccessed with the ceres pipeline which generates as final outputs the two dimensional spectrum, and the determination of precise radial velocities and bisector span measurements using the cross-correlation technique. The mean error of these radial velocity measurements was of 9 m / s. ceres performs also a rough estimation of the stellar parameters, and for the case of TOI-2485, we obtained T e ff = 5900 ± 100 K, log g ⋆ = 4.2 ± 0.2 dex [Fe / H] = 0 ± 0.1, and V sin i = 5 ± 1 kms -1 .', '2.3.5. TRES': 'TOI-2485 was observed 11 times from UT 2021 February 17 to February 27 using the Tillinghast Reflector Echelle Spectrograph (TRES; F"urész et al. 2008) 7 on the 1.5m Tillinghast Reflector at the Fred L. Whipple Observatory (FLWO) on Mt. Hopkins, AZ. TRES has a resolution of R = 44,000, and covers a spectral wavelength range of 3850-9096Å. The reduction process for TRES is described in detail in Buchhave et al. (2010), and the RV extraction process using a median combined template is presented in Quinn et al. (2012). To better understand the host star parameters, the spectra were analyzed using the Stellar Parameter Classification (SPC) package (Buchhave et al. 2012) providing a comparison constraint on the [Fe / H], T e ff , and rotational velocity of TOI-2485 of 0.005 ± 0.008 dex, 5982 ± 50 K, and 6.01 ± 0.05 km s -1 .', '2.4. High Resolution Imaging': 'As part of our standard process for validating transiting exoplanets to assess the the possible contamination of bound or unbound companions on the derived planetary radii (Ciardi et al. 2015), we observed TOI 2420 and TOI 2485 with optical speckle observations at SOAR and WIYN and near-infrared adaptive optics (AO) imaging at Palomar and Lick Observatories.', '2.4.1. Optical Speckle Imaging': "We searched for stellar companions to TOI-2420 and TOI-2485 with speckle imaging on the 4.1-m Southern Astrophysical Research (SOAR) telescope (Tokovinin 2018) on UT 2020 December 3 and 2021 February 27, respectively, observing in Cousins I-band, a similar visible bandpass as TESS. This observations were both sensitive to a 5.0-magnitude fainter star at an angular distance of 1 arcsec from the target. More details of the observations within the SOAR TESS survey are available in Ziegler et al. (2020). No nearby stars were detected within 3 '' of either TOI-2420 or TOI-2485 in the SOAR observations.", '2.4.2. NESSI': "We observed TOI-2485 on UT 2021 April 1 and UT 2022 April 18 using the NN-EXPLORE Exoplanet Stellar Speckle Imager (NESSI; Scott et al. 2018), a speckle imager employed at the WIYN 3.5 m telescope on Kitt Peak. NESSI was used to obtain simultaneous speckle imaging in two filters with central  \nFig. 4: NIR AO imaging and sensitivity curves for the Paloamr Observations of TOI-2485. Inset: Image of the central portion of the image. No nearby companions have been detected.  \n<!-- image -->  \nFig. 3: NESSI speckle imaging results from observations of TOI-2485 on 2021 April 1. Sensitivity curves and reconstructed images are shown for each filter (central wavelengths 562 and 832 nm). No nearby companions have been detected.  \n<!-- image -->  \nwavelengths λ c = 562 and 832 nm for the 2021 observation, but only the 832 nm was available for the 2022 observation. Each observation consisted of a set of 9 1000-frame 40 ms exposures. NESSI's field-of-view was limited to a 256 × 256 pixel sub-array readout, resulting in a 4 . 6 × 4 . 6 arcsecond field. However, our speckle measurements were further confined to an outer radius of 1.2 arcseconds from the target star. Speckle imaging of a point source standard star was taken in conjunction to each observation of the TOI. The standard observation consisted of a single 1000-frame image set and was used to calibrate the intrinsic PSF. These speckle data were reduced using the pipeline process described in Howell et al. (2011). Among the pipeline products are reconstructed images of the field around TOI-2485 in each filter. We used these to measure contrast curves, setting detection limits on point sources close to the TOI. No companion sources were detected for TOI-2485 (Fig. 3).", '2.4.3. Near-Infrared AO Imaging': "Observations of TOI-2485 were made on UT 2023 June 7 with the PHARO instrument (Hayward et al. 2001) on the Palomar Hale (5m) behind the P3K natural guide star AO system (Dekany et al. 2013) in the narrowband Brγ filter ( λ o = 2 . 1686; ∆ λ = 0 . 0326 µ m). The PHARO pixel scale is 0 . 025 '' per pixel. A standard 5-point quincunx dither pattern with steps of 5 '' was repeated twice with each repeat separated by 0.5 '' . The reduced science frames were combined into a single mosaiced image with a final resolutions of 0.21 '' . The sensitivity of the final combined AO image were determined by injecting simulated sources azimuthally around the primary target every 20 · at separations of integer multiples of the central source's FWHM (Furlan et al. 2017). The brightness of each injected source was scaled until standard aperture photometry detected it with 5 σ significance. The final 5 σ limit at each separation was determined from the average of all of the determined limits at that separation and the uncertainty on the limit was set by the rms dispersion of the azimuthal slices at a given radial distance. The Palomar sensitivities are shown in (Fig. 4).", '2.4.4. ShARCS': 'TOI-2485 was observed on UT 2021 March 04 using the ShARCS camera on the Shane 3-meter telescope at Lick Observatory (Kupke et al. 2012; Gavel et al. 2014; McGurk et al. 2014). Observations were taken with the Shane adaptive optics system in natural guide star mode in order to search for nearby, unresolved stellar companions. Sequences of observations were collected using a Ks filter ( λ 0 = 2 . 150 µ m, ∆ λ = 0 . 320 µ m) and a J filter ( λ 0 = 1 . 238 µ m, ∆ λ = 0 . 271 µ m). The data were reduced using the publicly available SImMER pipeline (Savel et al. 2020, 2022). 8 No stellar companions were found within detection limits. We refer the reader to Dressing et al. (in prep) for more information about these observations.', '3.1. Spectroscopic modelling of the host stars': 'We carried out spectroscopic modelling of the two exoplanet host stars using our co-added CHIRON spectra with the Spectroscopy Made Easy 9 (SME; Valenti & Piskunov 1996; Piskunov & Valenti 2017) version 5.2.2. This software fits spectral observations to synthetic spectra computed with atomic and molecular line data from VALD 10 (Ryabchikova et al. 2015) and different stellar atmosphere grids for a chosen set of parameters. We used the Atlas12 (Kurucz 2013) atmospheric model for both host stars. A more detailed description of the SME modelling can be found in (Persson et al. 2018). In summary, we fitted spectral lines sensitive to di ff erent parameters: the line wings of H α at 6 563Å to model T e ff , and the line wings of the Ca i lines at 6 102 Å, 6 122 Å, and 6162 Å for log g ⋆ . The abundances of iron, calcium, and sodium, and the projected rotational velocity ( V sin i ⋆ ), were fitted to narrow and unblended spectral lines between 5 900 Å and 6 600 Å. As a final check of the model, we fitted the Na doublet at 5888 Å and 5895 Å, sensitive to both gravity and e ff ective temperature. We fixed the micro-turbulent velocity, V mic to 1 km s -1 (Bruntt et al. 2008) for both host stars, and the macro-turbulent velocity, V mac to 4.1 km s -1 for TOI2420 and 4.4 km s -1 for TOI-2485 (Doyle et al. 2014).  \nAll SME results for both host stars are listed in Table 2 which are adopted as the final spectroscopic parameters.  \nThe surface gravities combined with the e ff ective temperatures suggests a G7 IV and G0 IV spectral type for TOI-2420 and TOI-2485, respectively (Pecaut & Mamajek 2013).', '3.2. Modelling of stellar masses and radii': 'The derived spectroscopic parameters from SME were used as priors in a spectral energy distribution (SED) fit (Fig. 5) with the publically available python package ARIADNE 11 (Vines & Jenkins 2022). This software fits the observed broadbad photometry to the SED from grids of four stellar models, constrained by the Gaia DR3 parallax and the dust maps of Schlegel et al. (1998) to obtain an upper limit on AV . We included the Johnson V and B from APASS, GG BP G RP from Gaia DR3, JHKS from 2MASS , and the WISE W1 and W2 photometry. The atmospheric model grids that were used in the fit were Phoenix v2 (Husser et al. 2013), BtSettl (Allard et al. 2012), Castelli & Kurucz (2004), and Kurucz (1993). The final stellar parameters were computed with Bayesian Model Averaging from the averaged posterior distributions of all four stellar models weighted by respective Bayesian evidence estimate. To account for an underestimation of the uncertainties, an excess noise term is added in ARIADNE to each set of parameters.  \nThe stellar mass is computed in two ways in ARIADNE. The first method determines a gravitational mass from a combination of the posterior log g ⋆ , and the computed R ⋆ . The second technique used by ARIADNE is an interpolation from the MIST (Choi et al. 2016) isochrones. We note that the posteriors of T e ff , log g ⋆ , and [Fe / H] in the ARIADNE model are in good agreement with results from SME for both targets (listed in Table 2).  \nThe resulting stellar masses and radii were checked with the online applet PARAM1.3 12 (da Silva et al. 2006) based on Bayesian computation and the PARSEC isochrones. Input was the Gaia DR3 parallax, T e ff , [Fe / H], the V magnitude. The results are in good agreement, within 1 σ , with the ARIADNE models for both host stars.  \nAll results are listed in Table 3 including the luminosity and stellar age derived with ARIADNE and PARAM1.3 . For the modelling of the planets in Sect. 4, we use the ARIADNE results.', '4. Planetary system modelling: joint fit': "We performed a joint RV and transit modelling for TOI-2420 b and TOI-2485 b. We use the code pyaneti /github (Barragán et al. 2019; Barragán et al. 2022) to model all of our data.  \nFor the transit analyses, we use the quadratic limb darkening framework by Mandel & Agol (2002). We use the q 1 and q 2 parametrisation given by Kipping (2013) to account for realistic limb darkening parameter values. We note that the FFI data are taken with long cadence of 30 and 10 min in di ff erent TESS sectors. For these cases we re-sampled the model to account for the data integration (Kipping 2010), using one integration step for every minute of integration of the data. For each planet we sample for the time of transit, T 0; orbital period, P orb; the polar parametrisation of the orbital eccentricity, e and angle of periastron, ω given as √ e cos ω and √ e sin ω (see Anderson et al. 2011); scaled planetary radius R p / R ⋆ and stellar density ρ⋆ (that connects with the scaled semi-major axis a / R ⋆ via Kepler's third  \nTable 1: Stellar properties of TOI-2420 and TOI-2485  \nlaw). We also sample for a photometric jitter term per band to penalise the imperfections of our transit model.  \nFor the RV data, we use one Keplerian signal for each system. This Keplerian signal is modelled with a time of minimum conjunction (or time of transit for transiting planets), T 0; orbital period, P orb; orbital eccentricity, √ e cos ω and √ e sin ω ; and Doppler semi-amplitude, K . We also include one o ff set to account for the systemic o ff set and a jitter term for every instrument in the corresponding data set. For TOI-2485, we also included a slope to model the trend visible in the FEROS time series.  \nTables 5 and 6 show the sampled parameters and priors used to model TOI-2420 b and TOI-2485 b, respectively. In all our runs we sample the parameter space with 250 walkers using a Markov chain Monte Carlo (MCMC) ensemble sampler algorithm (as implemented in pyaneti Barragán et al. 2019; Foreman-Mackey et al. 2013). We create the posterior distributions using the last 5000 iterations of converged chains, thinned with a thin factor of 10. This gives a distribution of 125 000 points for each sampled parameter.  \nWe ran di ff erent model combinations to model TOI-2420 b and TOI-2485 b, including circular and eccentric orbits, and linear and quadratic trends. We use the di ff erence of Akaike Information Criterion ( ∆ AIC) to find the best model. We decide to use the AIC because is more appropriate than BIC (Bayesian Information Criterion) in finding the best model when the true model is unknown (see discussion in Barragán et al. 2023). Table 4 summarises the results. We can conclude that the best model for TOI-2420 is an eccentric orbit with no trends on the RVs. As for TOI-2485 the best model is the one with a quadratic trend and an eccentric orbit. We also tested a 2-planet model, but the fit does not converge to any significant results.  \nThe inferred and derived parameters of TOI-2420 b and TOI2485 b are shown in Tables 5 and 6. Figures 6 and 7 show the inferred transit and RV models for both planets, while Fig. 8 displays the RVs time series for TOI-2485 where a linear trend is evident. We note that the TESS 2 min data in Fig. 7 looks flatbottomed. However, we underline that we account for the limb darkening coe ffi cients in the modelling, using uniform. In this particular case, the best solution is consistent with a flat bottom transit, suggesting that we cannot constrain the limb darkening of the star on the TESS band with that given transit dataset. However, we note that this does not a ff ect the inferred transit depth.  \nFig. 5: The spectral energy distribution (SED) for TOI-2420 ( left ) and TOI-2485 ( right ) and the best fitted models from (Phoenix v2 Husser et al. 2013). Magenta and blue diamonds are the synthetic and the observed photometry, respectively. Oneσ uncertainties of the magnitudes are marked with vertical bars, while the the horizontal bars show the e ff ective width of respective passband. The lower panels shows the residuals normalised to the errors of the photometry.  \n<!-- image -->  \nTable 2: Spectroscopic parameters for TOI-2420 and TOI-2485 modelled with SME. Posteriors from the ARIADNE modelling and the e ff ective stellar temperature from Gaia DR2 are listed for comparison.Notes. ( a ) Adopted as priors for the stellar mass and radius modelling with ARIADNE and PARAM 1.3 in Sect. 3.2. ( b ) Posteriors from Bayesian Model Averinging with ARIADNE.", '5.1. The inferred formation mechanism of TOI-2420 b and TOI-2485b': "Considering the orbital period of 10 days as the boundary between HJs and WJs, TOI-2420 b falls in the HJs category while TOI-2485 b in the WJs category. Both planets are common outcomes in core accretion models including disk migration (e.g., Ida et al. 2013; Emsenhuber et al. 2021; Schlecker et al. 2021a,b). To put them in the context of the close-in giant planets population, from the NASA Exoplanet Archive 13 we selected Jupiter-sized planets (mass between 0.20 and 12 M J ) with orbital periods shorter than 200 days, planetary masses with precision better than 20% and eccentricities with precision smaller than 0.1. With these criteria, over a total of 5595 exoplanets (as of March 13th) we found 158 Jupiter-sized planets, of which 131 are in single systems and 27 in multi-planet systems. Fig. 9 represents the eccentricity distribution of these two popula-  \ntions as function of the orbital period, showing that the majority of HJs orbiting within 3 days have circular orbits, while for increasing periods there is a wide variety of low and high eccentricities. This distribution challenges the evolution theories: disk migration cannot explain high eccentricities (i.e., Bitsch et al. 2013; Petrovich 2015b; Du ff ell & Chiang 2015), while higheccentricity tidal migration (Wu & Murray 2003) can explain the intermediate-high eccentricities of WJs with small pericenter distances, since tidal migration strongly depends on the distance from the star. The highly eccentric WJs might be the results of Kozai-Lidov oscillations or other secular oscillations caused by a third body (i.e., Dong et al. 2014; Petrovich & Tremaine 2016).  \nAn important facet to consider in constraining these planets' dynamical histories is the tidal dissipation. Both planets' orbits are nearly circular ( 0 . 055 + 0 . 036 -0 . 031 for TOI-2420 b and 0 . 0341 + 0 . 0109 -0 . 0087 for TOI-2485 b); could they have migrated by high-eccentricity migration and undergone tidal damping of eccentricity within the stars' main sequence lifetime? If not, we can exclude this migration method.  \nTable 3: Stellar parameters of TOI-2420 and TOI-2485 modelled with ARIADNE and PARAM 1.3.Notes. ( a ) ARIANDE uses SED fitting and MIST isochrones. We adopt these results as the final stellar parameters in the joint transit and RV modelling in Sect. 4. ( b ) Gravitational mass computed from log g ⋆ and R ⋆ modelled with astroARIADNE .  \nTable 4: Model comparison for di ff erent models for TOI-2420 and TOI-2485. Each element in the table shows the ∆ AIC for each model in comparison with the minimum AIC value for each system.  \nFor current purposes we pursue a simple computation. We use the eccentricity tidal damping timescales presented in Eqn. 1 of Dobbs-Dixon et al. (2004):  \nτ ep ≃ 5 GLYPH<18> Q ' P 10 6 GLYPH<19>GLYPH<18> MP MJ GLYPH<19>GLYPH<18> M ⋆ M ⊙ GLYPH<19> 2 / 3 GLYPH<18> P 1day GLYPH<19> 13 / 3 GLYPH<18> RP RJ GLYPH<19> -5 Myr (1)  \nThe tidal quality factor Q ' P is significantly unknown, however, using a nominal value of 10 5 predicts eccentricity damping timescales of 250 Myr and 32 Gyr for TOI-2420 and TOI-2485, respectively. This suggests that the former planet could have quickly tidally damped out any eccentricity for a range of tidal quality factors, while TOI-2485 would have required a low quality factor to damp out a high eccentricity within the age of the system.  \nWe can also consider whether any initial orbital obliquity, as predicted by some high-eccentricity migration models, could have been damped out. Albrecht et al. (2012) presented a formula (Eqn. 2 of that work) for the obliquity tidal dissipation timescale of a convective-envelope star like TOI-2420 or TOI2485, based upon the theory of Zahn (1977) and calibrated using binary stars. This is:  \n1 τ CE = 1 10 × 10 9 yr q 2 GLYPH<18> a / R ⋆ 40 GLYPH<19> -6 (2)  \nwhere τ CE is the tidal damping timescale and q is the planetaryto-stellar mass ratio.  \nWith the current parameters for both systems, the estimated obliquity damping timescales are > 10 11 years, well in excess of the main sequence lifetimes in either system. Additionally, considering that both stars are slightly evolved and the current  \nvalue of a / R ⋆ is smaller than it was on the main sequence, these estimated tidal damping timescales may be underestimates . Further information on their history can be obtained from the observations of the Rossiter-McLaughlin (RM) e ff ect, as the long tidal obliquity timescales suggest that any initial orbital obliqity should be retained. The expected semi-amplitude of the RM is ∼ 5 m s -1 and ∼ 15 m s -1 for TOI-2420 b and TOI-2485 b, respectively. Wang et al. 2024 present the RM for TOI-2485 b, showing that the system is well aligned, implying a quiet formation history.", '5.2. Evidence for a long-period companion to TOI-2485': "If we assume that the linear acceleration of TOI-2485 (-0.389 ± 0.009 m / s / days from the linear trend model) is caused by another orbiting body, we can place some constraints on the nature of that body and its orbit. Following equation 2 of Smith et al. (2017) (which is derived from equation 2 of Liu et al. 2002) we can place the following constraint on the mass and orbital separation of planet 'c':  \nM c a 2 c > 2 . 06 MJup au -2 (3)  \nFurthermore, assuming an approximately circular orbit for 'c' implies an orbital period greater than twice our RV baseline, i.e. P c > 1800 d. This corresponds to a c > 3 au, and leads to (from Eqn. 3) a lower mass limit of 18 MJup. For circular orbits, the third body would lie in the brown dwarf mass regime for 3 < a / au < 6 . 3. Alternative possibilities are a low-mass star orbiting further out, or a more massive object on a highly-eccentric  \nTable 5: Model parameters and priors for TOI-2420 b's joint fit  \nNotes. ( a ) U [ a , b ] refers to an uniform prior between a and b , N [ a , b ] to a Gaussian prior with mean a and standard deviation b , and J [ a , b ] to the modified Je ff rey's prior as defined by Gregory (2005, eq. 16). ( b ) Inferred parameters and errors are defined as the median and 68.3% credible interval of the posterior distribution. ( c ) Assuming a zero albedo.  \nTable 6: Model parameters and priors for TOI-2485 b's joint fit  \nNotes. ( a ) U [ a , b ] refers to an uniform prior between a and b , N [ a , b ] to a Gaussian prior with mean a and standard deviation b , and J [ a , b ] to the modified Je ff rey's prior as defined by Gregory (2005, eq. 16). ( b ) Inferred parameters and errors are defined as the median and 68.3% credible interval of the posterior distribution. ( c ) Assuming a zero albedo.  \nFig. 7: Top panel: Phase-folded transit light curve TOI-2485 b. Nominal TESS and LCO observations are shown in light grey. Solid coloured circles represent the binned data. Transit models are shown with a solid black line. Bottom panel: Phase-folded RV signal for TOI-2485 b following the subtraction of the systemic velocities. Orange circles, diamonds and squares show CHIRON, FEROS and TRES RV data, respectively.  \n<!-- image -->  \n<!-- image -->  \n<!-- image -->  \nFig. 6: Top panel: Phase-folded transit light curve TOI-2420 b. Nominal TESS and LCO observations are shown in light grey. Solid coloured circles represent the binned data. Transit models are shown with a solid black line. Bottom panel: Phase-folded RV signal for TOI-2420 b following the subtraction of the systemic velocity. Blue circles and triangles show the CHIRON and TULLRVdata, respectively, while green squares, red pentagons, purple hexagons and brown circles show the M inerva RVs, split in 4 di ff erent datasets.  \n<!-- image -->  \norbit. Using equation (4) of Jackson et al. (2021), we are able to assess whether this putative third body is capable of inducing high-eccentricity tidal migration. A perturber at 3 au whose orbit is aligned with that of TOI-2485 b, must have a mass greater than 7 . 3 MJup; in other words a 3 au, 18 MJup object meets the minimum requirement for high-eccentricity tidal migration.  \nRV surveys of WJs aimed at detecting long-term trends would be highly valuable in determining if perturber-coupled high eccentricity migration is the dominant mechanism. TOI-  \n2485 b, exhibiting a significant long-term trend, provides a promising connection to this hypothesis as suggested by Jackson et al. (2021).", '5.3. Planets orbiting evolved stars': "Both TOI-2420 b and TOI-2485 b orbit slightly evolved stars. When a main sequence star exhausts the hydrogen in its core, the core contracts, while the temperature rises enough to ignite the fusion of hydrogen in a shell surrounding the core (see, e.g., Lamers & Levesque 2017). Prior to becoming a red giant, the  \nFig. 8: TOI-2485's RV time series. The trend in the data is clear and it has been modelled with a quadratic trend, whose significance is higher with respect of a  \n<!-- image -->  \nlinear trend model.  \nevolving star undergoes a transition phase called subgiant phase, during which the star lies between the main sequence turn-o ff and the base of the red giant branch in the HR diagram (see, e.g., Pinsonneault & Ryden 2023). During the subgiant phase, the outer layers of the star expand, while the e ff ective temperature decreases, profoundly a ff ecting the evolution and the fate of the surrounding planetary system. The strong tidal interaction between a close-in planet and its expanding host star is expected to play a crucial role in shaping the structure of the inner region of a planetary system (Villaver & Livio 2009a; Veras 2016; Grunblatt et al. 2018; MacLeod et al. 2018).  \nBased on radial velocity follow-up observations of about 500 bright (V < 8.5) sub-giant stars, the Lick, Keck, and California planet-search programs (Johnson et al. 2006; Sato et al. 2008; Peek et al. 2009; Luhn et al. 2019) found a paucity of hot Jupiters orbiting sub-giant stars with respect to main sequence stars. This result suggests that close-in planets might be engulfed by their evolving host star during the subgiant / giant phase (e.g., Villaver & Livio 2009b; Bowler et al. 2010; Villaver et al. 2014). Grunblatt et al. (2019) carried out a search of transiting planets in a sample of nearly 2500 low-luminosity red giant branch stars observed by NASA K2 mission and found that short-period (P < 10 d) planets larger than Jupiter seem to be more common around evolved stars than main sequence stars. This would suggest that close-in planets larger than Jupiter can survive the subgiant phase, at least while their host stars have radii smaller than 5-6 R ⊙ .  \nOnly a few transiting planets with measured masses and radii, around sub-giant stars have been discovered so far from both ground- (e.g., Lillo-Box et al. 2016; Pepper et al. 2017; Grieves et al. 2021; Kabáth et al. 2022; Smith et al. 2022) and space-based transit-search surveys (e.g., Borucki et al. 2010; Rowe et al. 2014; Ortiz et al. 2015; Morton et al. 2016; Wang et al. 2019). To increase our knowledge on the evolution of planetary systems during the post-main sequence phase of their host stars, it it crucial to increase the sample of well-characterized planets orbiting evolved stars.", '6. Conclusions': 'This paper presents the discovery of two Jupiter-sized planets. TOI-2420 b has been observed by TESS in Sectors 3 and 30, followed-up through LCO ground-based photometry and CH-  \nIRON, TULL and M inerva -Australis spectroscopy. We found TOI-2420 b to have an orbital period of 5.8 days, a mass of 0.9 MJ and a radius of 1.3 RJ. TOI-2485 b has been observed by TESS during Sectors 23 and 50. We collected LCO photometry, and CHIRON, FEROS and TRES RVs data in order to constrain the orbital properties. TOI-2485 b has an orbital period of 11.2 days, a mass of 2.4 MJ and a radius of 1.1 RJ.  \nThe observed characteristics of the two planetary systems and the calculation of the tidal damping timescale indicates that the high-eccentricity migration (HEM) scenario cannot be ruled out for both systems, especially due to the large uncertainties in the tidal quality factor. Moreover, regarding TOI-2485 b, the possible non-zero eccentricity and the evidence for a long period companion may support some HEM scenarios such as coplanar high-eccentricity migration (Petrovich 2015a).  \n0.00  \nFig. 9: Eccentricity distribution as a function of the orbital period for Jupiter-sized planets (data taken as of UT 2024 March 13). The dashed blue line represents the 10-day boundary between HJs and WJs. The orange point represents TOI-2420 b, while the cyan point represents TOI-2485 b. The red triangles represent the planets in multi-planetary systems.  \n<!-- image -->', 'Appendix A: Tables of Radial velocity data.': 'Table A.1: Time series of TOI-2420 from CHIRON, Tull and Minerva-Australis data. We list the radial velocities and the corresponding uncertainties.  \nTable A.2: Time series of TOI-2485 from CHIRON, TRES and FEROS data. The radial velocities and corresponding uncertainties are listed.  \nCarleo et al.: Mass determination of two Jupiter-sized planets orbiting slightly evolved stars: TOI-2420 b and TOI-2485 b  \n10048.753340  \n-26.4934  \n8.6  \n10067.676020  \n-26.8165 8.3  \n10125.490250  \n-26.6566  \n9.4  \n10127.462530  \n-26.5031  \n7.6  \n10128.513330  \n-26.4996  \n8.4  \nAcknowledgements. C.M.P. and M.F. gratefully acknowledge the support of the Swedish National Space Agency (DNR 65 / 19 and 177 / 19). O.B. acknowledges that has received funding from the European Research Council (ERC) under the European Union\'s Horizon 2020 research and innovation programme (Grant agreement No. 865624). G.N. thanks for the research funding from the Ministry of Education and Science programme the "Excellence Initiative - Research University" conducted at the Centre of Excellence in Astrophysics and Astrochemistry of the Nicolaus Copernicus University in Toru\'n, Poland. P.K. acknowledges funding from LTT-20015 project. D.G. gratefully acknowledges the financial support from the grant for internationalization (GAND\\_GFI\\_23\\_01) provided by the University of Turin (Italy). M.T.P. acknowledges support from the FondecytANID Post-doctoral fellowship 3210253 and from the ANID Project ASTRO210037. A.J. and R.B. acknowledge support from ANID - Millennium Science Initiative - ICN12\\_009. R.B. acknowledges support from FONDECYT Project 1241963. A.J. acknowledges support from FONDECYT project 1210718. 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 research has made use of the Exoplanet Follow-up Observation Program (ExoFOP; DOI: 10.26134 / ExoFOP5) website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Funding for the TESS mission is provided by NASA\'s Science Mission Directorate. KAC and CNW acknowledge support from the TESS mission via subaward s3449 from MIT. DRC and CAC acknowledge partial support from NASA Grant 18-2XRP18\\_2-0007. This research has made use of the Exoplanet Follow-up Observation Program (ExoFOP; DOI: 10.26134 / ExoFOP5) website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. M inerva -Australis is supported by Australian Research Council LIEF Grant LE160100001, Discovery Grants DP180100972 and DP220100365, Mount Cuba Astronomical Foundation, and institutional partners University of Southern Queensland, UNSW Sydney, MIT, Nanjing University, George Mason University, University of Louisville, University of California Riverside, University of Florida, and The University of Texas at Austin. We respectfully acknowledge the traditional custodians of all lands throughout Australia, and recognise their continued cultural and spiritual connection to the land, waterways, cosmos, and community. We pay our deepest respects to all Elders, ancestors and descendants of the Giabal, Jarowair, and Kambuwal nations, upon whose lands the M inerva -Australis facility at Mt Kent is situated. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). The results reported herein benefitted from collaborations and / or information exchange within NASA\'s Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA\'s Science Mission Directorate under Agreement No. 80NSSC21K0593 for the program \'Alien Earths". This work is partly supported by JSPS KAKENHI Grant Number JPJP24H00017 and JSPS Bilateral Program Number JPJSBP120249910.', 'References': 'Addison, B., Wright, D. J., Wittenmyer, R. A., et al. 2019, PASP, 131, 115003 Addison, B. C., Wright, D. J., Nicholson, B. A., et al. 2021, MNRAS, 502, 3704 Albrecht, S., Winn, J. 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W. 2023, ApJ, 956, L29  \n- 1 INAF - Osservatorio Astrofisico di Torino, Via Osservatorio 20, I10025, Pino Torinese, Italy\n- e-mail: ilaria.carleo@inaf.it\n- 2 Instituto de Astrofísica de Canarias (IAC), 38205 La Laguna, Tenerife, Spain\n- 3 Departamento de Astrofísica, Universidad de La Laguna (ULL), E38206 La Laguna, Tenerife, Spain\n- 4 Sub-department of Astrophysics, Department of Physics, University of Oxford, Oxford, OX1 3RH, UK\n- 5 Chalmers University of Technology, Department of Space, Earth and Environment, Onsala Space Observatory, SE-439 92 Onsala, Sweden.\n- 6 Leiden Observatory, University of Leiden, PO Box 9513, 2300 RA, Leiden, The Netherlands\n- 7 Institute of Planetary Research, German Aerospace Center (DLR), Rutherfordstrasse 2, 12489 Berlin, Germany\n- 8 INAF - Osservatorio Astrofisico di Catania, Via S. Sofia 78, I-95123, Catania, Italy\n- 9 Dipartimento di Fisica, Università degli Studi di Torino, via Pietro Giuria 1, I-10125, Torino, Italy\n- 10 Department of Astronomy, The Ohio State University, 4055 McPherson Laboratory, 140 West 18th Avenue, Columbus, OH 43210 USA\n- 11 Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK\n- 12 European Southern Observatory, Karl-Schwarzschild-Straße 2, D85748 Garching bei Munchen, Germany\n- 13 Facultad de Ingeniera y Ciencias, Universidad Adolfo Ibáñez, Av. Diagonal las Torres 2640, Peñalolén, Santiago, Chile\n- 14 Millennium Institute for Astrophysics, Chile\n- 15 NASA Exoplanet Science Institute-Caltech / IPAC, Pasadena, CA 91125, USA\n- 16 Center for Astrophysics | Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA\n- 17 Department of Astronomy and McDonald Observatory, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712, USA\n- 18 NSF National Optical-Infrared Astronomy Research Laboratory, 950 N. Cherry Ave., Tucson, AZ 85719, USA\n- 19 Department of Astronomy, California Institute of Technology, Pasadena, CA 91125, USA\n- 20 Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenberg, Germany\n- 21 Astrophysics Group, Keele University, Sta ff ordshire, ST5 5BG, UK\n- 22 Astronomical Institute, Czech Academy of Sciences, Friˇcova 298, 25165, Ondˇrejov, Czech Republic\n- 23 Lund Observatory, Division of Astrophysics, Department of Physics, Lund University, Box 43, 22100 Lund, Sweden\n- 24 Institute of Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudzia¸dzka 5, 87-100 Toru\'n, Poland\n- 25 Center for Data Intensive and Time Domain Astronomy, Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA\n- 26 University of Southern Queensland, Centre for Astrophysics, UniSQ Toowoomba, West Street, QLD 4350, Australia\n- 27 Department of Physics, Engineering and Astronomy, Stephen F. Austin State University, 1936 North St, Nacogdoches, TX 75962, USA\n- 28 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA\n- 29 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 USA\n- 30 Department of Astronomy, University of California Berkeley, Berkeley, CA 94720, USA  \n- 31 Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany\n- 32 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA\n- 33 Department of Physics & Astronomy, Texas Tech University, Lubbock TX, 79410-1051, USA\n- 34 Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA\n- 35 Department of Astronomy, University of Florida, Gainesville, FL 32611, USA\n- 36 Observatoire de Genève, Département d\'Astronomie, Université de Genève, Chemin Pegasi 51b, 1290 Versoix, Switzerland\n- 37 NASA Ames Research Center, Mo ff ett Field, CA 94035, USA\n- 38 Department of Physics and Astronomy, University of New Mexico, 210 Yale Blvd NE, Albuquerque, NM, USA\n- 39 Komaba Institute for Science, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan\n- 40 Astrobiology Center, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan\n- 41 Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Chile\n- 42 Department of Astronomy, University of Maryland, College Park, College Park, MD 20742 USA\n- 43 Department of Astronomy / Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA\n- 44 Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA\n- 45 Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA\n- 46 SETI Institute, 339 N Bernardo Ave Suite 200, Mountain View, CA 94043, USA\n- 47 Department of Physics & Astronomy, Vanderbilt University, Nashville, TN, USA\n- 48 Hazelwood Observatory, Australia\n- 49 Department of Astronomy, Sofia University \'St Kliment Ohridski\', 5 James Bourchier Blvd, BG-1164 Sofia, Bulgaria\n- 50 Landessternwarte, Zentrum für Astronomie der Universität Heidelberg, Königstuhl 12, D-69117 Heidelberg, Germany\n- 51 CAS Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China\n- 52 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA'}