J/A+A/702/A32 TOI-2322 ESPRESSO and HARPS RVs (Hobson+, 2025)
TOI-2322: two transiting rocky planets close to the stellar rotation period and
its first harmonic.
Hobson M.J., Suarez Mascareno A., Lovis C., Bouchy F., Lavie B.,
Cretignier M., Silva A.M., Sousa S.G., Tabernero H.M., Adibekyan V.,
Allende Prieto C., Alibert Y., Barros S.C., Castro-Gonzalez A.,
Collins K.A., Cristiani S., D'Odorico V., Damasso M., Dragomir D.,
Dumusque X., Ehrenreich D., Figueira P., Genova Santos R., Goeke B.,
Gonzalez Hernandez J.I., Hesse K., Lillo-Box J., Lo Curto G.,
Martins C.J.A.P., Mehner A., Micela G., Molaro P., Nunes N.J., Palle E.,
Passegger V.M., Pepe F., Rebolo R., Rodrigues J., Santos N., Sozzetti A.,
Tofflemire B.M., Udry S., Watkins C., Zapatero Osorio M.-R., Ziegler C.
<Astron. Astrophys. 702, A32 (2025)>
=2025A&A...702A..32H 2025A&A...702A..32H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, K-type ; Exoplanets ;
Radial velocities ; Optical ; Spectroscopy
Keywords: techniques: photometric - techniques: radial velocities -
planets and satellites: composition -
planets and satellites: detection - stars: individual: TOI-2322 -
stars: rotation
Abstract:
Active regions on the stellar surface can induce
quasi-periodic radial velocity (RV) variations that can mimic planets
and mask true planetary signals. These spurious signals can be
problematic for RV surveys such as those carried out by the ESPRESSO
consortium.
Using ESPRESSO and HARPS RVs and activity indicators, we aim to
confirm and characterize two candidate transiting planets from TESS
orbiting a K4 star with strong activity signals.
From the ESPRESSO FWHM, TESS photometry, and ASAS-SN photometry, we
measure a stellar rotation period of 21.28±0.08d. We jointly model
the TESS photometry, ESPRESSO and HARPS RVs, and activity indicators,
applying a multivariate Gaussian Process (GP) framework to the
spectroscopic data.
We are able to disentangle the planetary and activity components,
finding that TOI-2322 b has a 11.307170+0.000085-0.000079d period,
close to the first harmonic of the rotation period, a 2.03M⊕
mass upper limit and a 0.994+0.057-0.059R⊕ radius.
TOI-2322 c orbits close to the stellar rotation period, with a
20.225528+0.000039-0.000044d period; it has a
18.10+4.34-5.36M⊕ mass and a
1.874+0.066-0.057R⊕ radius.
The multivariate GP framework is crucial to separating the stellar and
planetary signals, significantly outperforming a one-dimensional GP.
Likewise, the transit data is fundamental to constraining the periods
and epochs, enabling the retrieval of the planetary signals in the
RVs. The internal structure of TOI-2322 c is very similar to that of
Earth, making it one of the most massive planets with an Earth-like
composition known. Description: Radial velocities and activity
indicators from ESPRESSO and HARPS for TOI-2322,
Description:
TOI-2322 was observed by the ESPRESSO GTO 33 times between 13 November
2022 and 26 March 2023, after the 2019 fibre link replacement, under
program IDs 110.24CD.002, 110.24CD.003, and 110.24CD.009 (P.I. F.
Pepe).
TOI-2322 was observed with HARPS 19 times between 8 October 2022 and
16 January 2023, under program ID 110.242T.001 (P.I. R. Rebolo). The
observations were done with an exposure time of 2700s.
Objects:
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RA (2000) DE Designation(s)
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07 47 53.52 -71 00 06.26 TOI-2322 = TIC 300812741
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
espresso.dat 132 33 TOI-2322 ESPRESSO radial velocities (table C1)
harps.dat 132 19 TOI-2322 HARPS radial velocities (table C2)
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Byte-by-byte Description of file: espresso.dat harps.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 d BJD Baricentric Julian date (BJD-2457000)
11- 18 F8.2 m/s RV Radial velocity
20- 23 F4.2 m/s e_RV Radial velocity error
25- 29 F5.2 --- Bis CCF Bisector
31- 34 F4.2 --- e_Bis CCF Bisector error
36- 42 F7.2 --- FWHM CCF full width at half maximum
44- 47 F4.2 --- e_FWHM CCF full width at half maximum error
49- 55 F7.4 --- Cont CCF Contrast
57- 62 F6.4 --- e_Cont CCF Contrast error
64- 71 F8.6 --- Halpha Halpha activity indicator
73- 80 F8.6 --- e_Halpha Halpha activity indicator error
82- 88 F7.5 --- SMW S Mount Wilson activity indicator
90- 96 F7.5 --- e_SMW S Mount Wilson activity indicator error
98-105 F8.5 --- log(R'HK) log(R'HK) activity indicator
107-113 F7.5 --- e_log(R'HK) log(R'HK) activity indicator error
115-122 F8.6 --- NaI NaI doublet activity indicator
124-132 F9.7 --- e_NaI NaI doublet activity indicator error
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Acknowledgements:
Melissa Hobson, Melissa.Hobson(at)unige.ch
(End) Patricia Vannier [CDS] 27-Aug-2025