J/A+A/695/A281 TOI-2015 light curves (Barkaoui+, 2025)
TOI-2015 b: A sub-Neptune in strong gravitational interaction with
an outer non-transiting planet.
Barkaoui K., Korth J., Gaidos E., Agol E., Parviainen H., Pozuelos F.J.,
Palle E., Narita N., Grimm S., Brady M., Bean J.L., Morello G.,
Rackham B.V., Burgasser A.J., Van Grootel V., Rojas-Ayala B., Seifahrt A.,
Marfil E., Passegger V.M., Stalport M., Gillon M., Collins K.A., Shporer A.,
Giacalone S., Yalcinkaya S., Ducrot E., Timmermans M., Triaud A.H.M.J.,
de Wit J., Soubkiou A., Watkins C.N., Aganze C., Alonso R., Amado P.J.,
Basant R., Bastuerk Oe., Benkhaldoun Z., Burdanov A., Calatayud-Borras Y.,
Chouqar J., Conti D.M., Collins K.I., Davoudi F., Delrez L., Dressing C.D.,
de Leon J., Devora-Pajares M., Demory B.O., Dransfield G.,
Esparza-Borges E., Fernandez-Rodriguez G., Fukuda I., Fukui A.,
Gallardo P.P.M., Garcia L., Garcia N.A., Ghachoui M., Geraldia-Gonzalez S.,
Gomez Maqueo Chew Y., Gonzalez-Rodriguez J., Guenther M.N., Hayashi Y.,
Horne K., Hooton M.J., Hsu C.C., Ikuta K., Isogai K., Jehin E.,
Jenkins J.M., Kawauchi K., Kagetani T., Kawai Y., Kasper D., Kielkopf J.F.,
Klagyivik P., Lacedelli G., Latham D.W., Libotte F., Luque R.,
Livingston J.H., Mancini L., Massey B., Mori M., Munoz Torres S., Murgas F.,
Niraula P., Orell-Miquel J., Rapetti D., Rebolo-Lopez R., Ricker G.,
Papini R., Pedersen P.P., Pelaez-Torres A., Perez-Prieto J.A.,
Poultourtzidis E., Rodriguez P.M., Queloz D., Savel A.B., Schanche N.,
Sanchez-Benavente M., Sibbald L., Sefako R., Sohy S., Sota A., Schwarz R.P.,
Seager S., Sebastian D., Southworth J., Stangret M., Stefansson G.,
Stuermer J., Srdoc G., Thompson S.J., Terada Y., Vanderspek R., Wang G.,
Watanabe N., Wilkin F.P., Winn J., Wells R.D., Ziegler C.,
Zuniga-Fernandez S.
<Astron. Astrophys. 695, A281 (2025)>
=2025A&A...695A.281B 2025A&A...695A.281B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry ; Optical
Keywords: planets and satellites: detection -
planets and satellites: formation - stars: individual: TOI-2015
Abstract:
TOI-2015 is a known exoplanetary system around an M4 dwarf star,
consisting of a transiting sub-Neptune planet in a 3.35-day orbital
period, TOI-2015 b, accompanied by a non-transiting companion,
TOI-2015 c. High-precision radial velocity measurements were taken
with the MAROONX spectrograph, and high-precision photometric data
were collected, primarily using the SPECULOOS, MUSCAT, TRAPPIST and
LCOGT networks. We collected 63 transit light curves and 49 different
transit epochs for TOI-2015 b. We re-characterize the target star by
combining optical spectra obtained by the MAROON-X, Shane/KAST and
IRTF/SpeX spectrographs, Bayesian Model Averaging (BMA) and Spectral
Energy Distribution (SED) analysis. The TOI-2015 host star is a
K=10.3mag M4-type dwarf with a sub-solar metallicity of
[e/H]=-0.31±0.16, and an effective temperature of Teff~=3200K. Our
photodynamical analysis of the system strongly favors the 5:3 mean
motion resonance and in this scenario the planet b (TOI-2015 b) has an
orbital period of Pb=3.34 days, a mass of
Mp=9.02+0.32-0.36M⊕, a radius of
Rp=3.309+0.0130.011R⊕, resulting in a density of
ρp=0.25±0.01ρ⊕=1.40±0.06g/cm3, indicative of a
Neptune-like composition. Its transits exhibit large (>1hr) timing
variations indicative of an outer perturber in the system.We performed
a global analysis of the high-resolution radial-velocity measurements,
the photometric data, and the TTVs, and inferred that TOI-2015 hosts a
second planet, TOI-2015 c, in a non-transiting configuration. Our
analysis places it near a 5:3 resonance with an orbital period of
Pc=5.583 days and a mass of Mp=8.91+0.38-0.40 M⊕. The
dynamical configuration of TOI-2015 b and TOI- 2015 c can be used to
constrain the system's planetary formation and migration history.
Based on the mass-radius composition models, TOI-2015 b is a
water-rich or rocky planet with a hydrogen-helium envelope. Moreover,
TOI-2015 b has a high transmission spectroscopic metric (TSM=149),
making it a favorable target for future transmission spectroscopic
observations with JWST to constrain the atmospheric composition of the
planet. Such observations would also help to break the degeneracies in
theoretical models of the planet's interior structure.
Description:
The host star TIC 368287008 (TOI-2015) was observed by TESS in Sectors
24, 51 and 78 for 27 days each with 2-min cadence.
The Sector 51 campaign started on 2022 Apr 22 and ended on 2022 May
18. The two gaps during Sector 51, were caused by scattered light and
high background levels1, and we ignored them. The Sector 78 campaign
started on 2024 Apr 23 and ended on 2024 May 21. The target was
observed in Camera 1 CCD3.
Objects:
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RA (2000) DE Designation(s)
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15 28 31.84 +27 21 39.86 TOI 2015 = TIC 368287008
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
lc.dat 111 26644 TOI-2015b light curves for 5:3 scenario
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See also:
J/AJ/168/93 : Phot. follow-up of TOI-2015 + discovery of TOI-2015b
(Jones+, 2004)
Byte-by-byte Description of file: lc.dat
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Bytes Format Units Label Explanations
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1- 16 F16.8 d Time UTC observation date, BJD (time)
18- 34 F17.15 --- Fluxobs Relative flux (flux_obs)
36- 52 F17.15 --- e_Fluxobs Relative flux error (fluxobserr)
54- 70 F17.15 --- Fluxmod Transit fit model (flux_mod)
72- 88 F17.15 --- b_Fluxmod Transit fit model (low part) (fluxmodlow)
90-106 F17.15 --- B_Fluxmod Transit fit model (upper part) (fluxmodhigh)
108-111 I4 --- Epoch Epoch (epoch)
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Acknowledgements:
Barkaoui Khalid, khalid.barkaoui(at)uliege.be
(End) Patricia Vannier [CDS] 20-Mar-2025