J/A+A/704/A41 TOI-282 radial velocities and activity indicators (Barone+, 2025)
Mass determination of the three long-period Neptune- and sub-Neptune-sized
planets transiting TOI-282.
Barone A., Rodler F., Gandolfi D., Bonfanti A., Leonardi P., Visca L.,
Fridlund M., Brogi M., Fossati L., Cubillos P.E., Cochran W.D.,
Csizmadia S., Livingston J., Nowak G., Palle E., Persson C.M., Redfield S.,
Schmerling H., Smith A.M.S.
<Astron. Astrophys. 704, A41 (2025)>
=2025A&A...704A..41B 2025A&A...704A..41B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities ;
Spectroscopy
Keywords: planets and satellites: composition -
planets and satellites: dynamical evolution and stability -
planets and satellites: fundamental parameters -
planets and satellites: general -
planets and satellites: physical evolution
Abstract:
TOI-282 is a bright (V=9.38) F8 main-sequence star known to host three
transiting long-period (Pb=22.9d, Pc=56.0d, Pd=84.3d) small
(Rp~=2-4R⊕) planets. The orbital period ratio of the two
outermost planets, namely TOI-282 c and d, is close to the 3:2
commensurability, suggesting that the planets might be trapped in a
mean motion resonance. We combined space-borne photometry from the
TESS telescope with high-precision HARPS and ESPRESSO Doppler
measurements to refine orbital parameters, measure the planetary
masses, and investigate the architecture and evolution of the system.
We performed a Markov chain Monte Carlo joint analysis of the transit
light curves and radial velocity time series, and carried out a
dynamical analysis to model transit timing variations and Doppler
measurements along with N-body integration. In agreement with previous
results, we found that TOI-282 b, c, and d have radii of
Rb=2.69±0.23 R⊕, Rc=4.13+0.16-0.14R⊕, and
Rd=3.11±0.15R⊕, respectively. We measured planetary masses
of Mb=6.2±1.6M⊕, Mc=9.2±2.0M⊕, and
Md=5.8+0.9-1.1M⊕, which imply mean densities of
ρb=1.8+0.7-0.6g/cm3, ρc=0.7±0.2g/cm3, and
ρd=1.1+0.3-0.2g/cm3, respectively. The three planets may be
water worlds, making TOI-282 an interesting system for future
atmospheric follow-up observations with JWST and ELT.
Description:
Radial velocity measurements (raw and detrended), full width at half
maximum (FWHM), contrast, and skewness extracted from the
cross-correlation functions of TOI-282's HARPS and ESPRESSO spectra.
Barycentric Julian dates are given in barycentric dynamical time minus
2450000. The last two columns provide the exposure time and S/N per
pixel at 550nm. he errors associated with the detrended RV
measurements account for the jitter. The ESPRESSO data set is split
into the ESPRESSO 1st and 2nd sets, as in November and December 2020,
ESPRESSO underwent an upgrade, and we wanted to account for a possible
RV offset.
Objects:
----------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------
04 20 57.13 -68 06 09.5 TOI-282 = HD 28109
----------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
harpsrv.dat 184 37 HARPS radial velocities (table B1)
espres1.dat 173 8 ESPRESSO 1st set radial velocities (table B3)
espres2.dat 196 36 ESPRESSO 2nd set radial velocities (table B1)
harpsai.dat 91 37 TOI-282's activity indicators extracted with HARPS
(table B2)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: harpsrv.dat espres2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 F16.11 d BJD Barycentric Julian date (TDB)
18- 43 E26.19 km/s RV Radial velocities (raw)
45- 64 F20.18 km/s e_RV RV sigma (raw)
66- 93 E28.21 km/s RVdetr Radial velocities (detrended)
95-115 F21.19 km/s e_RVdetr RV sigma (detrended)
117-132 F16.13 km/s FWHM CCF's FWHM
134-149 F16.13 % Contrast CCF's height
151-171 F21.18 --- Skewness CCF's skewness
173-178 F6.1 s Texp Exposure time
180-196 F17.13 --- S/N Signal to noise ratio
--------------------------------------------------------------------------------
Byte-by-byte Description of file: espres1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 F16.11 d BJD Barycentric Julian date (TDB)
18- 38 F21.18 km/s RV Radial velocities (raw)
40- 59 F20.18 km/s e_RV RV sigma (raw)
61- 82 F22.19 km/s RVdetr Radial velocities (detrended)
84- 94 F11.9 km/s e_RVdetr RV sigma (detrended)
96-111 F16.13 km/s FWHM CCF's FWHM
113-128 F16.13 % Contrast CCF's height
130-149 F20.17 --- Skewness CCF's skewness
150-155 F6.1 s Texp Exposure time
157-173 F17.13 --- S/N Signal to noise ratio
--------------------------------------------------------------------------------
Byte-by-byte Description of file: harpsai.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 17 F17.12 d BJD Barycentric Julian date (TDB)
19- 25 F7.4 --- logRHK CaII H&K chromospheric index
27- 32 F6.4 --- e_logRHK logRHK sigma
34- 52 F19.17 0.1nm NaD1 NaD1 line activity indicator
54- 72 F19.17 0.1nm NaD2 NaD2 line activity indicator
74- 91 F18.16 0.1nm Halpha Halpha line activity indicator
--------------------------------------------------------------------------------
Acknowledgements:
Andrea Barone, ab.baroneandrea(at)gmail.com
(End) Andrea Barone [SU, Sweden], Patricia Vannier [CDS] 28-Oct-2025