J/A+A/686/A230 NGTS-30 b/TOI-4862 b velocity curve (Battley+, 2024)
NGTS-30 b/TOI-4862 b: An ∼1 Gyr old 98-day transiting warm Jupiter.
Battley M.P., Collins K.A., Ulmer-Moll S., Quinn S.N., Lendl M., Gill S.,
Brahm R., Hobson M.J., Osborn H.P., Deline A., Faria J.P., Claringbold A.B.,
Chakraborty H., Stassun K.G., Hellier C., Alves D.R., Ziegler C.,
Anderson D.R., Apergis I., Armstrong D.J., Bayliss D., Beletsky Y.,
Bieryla A., Bouchy F., Burleigh M.R., Butler R.P., Casewell S.L.,
Christiansen J.L., Crane J.D., Dalba P.A., Daylan T., Figueira P.,
Gillen E., Goad M.R., Guenther M.N., Henderson B.A., Henning T.,
Jenkins J.S., Jordan A., Kanodia S., Kendall A., Kunimoto M., Latham D.W.,
Levine A.M., McCormac J., Moyano M., Osborn A., Osip D., Pritchard T.A.,
Psaridi A., Rice M., Rodriguez J.E., Saha S., Seager S., Shectman S.A.,
Smith A.M.S., Teske J.K., Ting E.B., Udry S., Vines J.I., Watson C.A.,
West R.G., Wheatley P.J., Winn J.N., Yee S.W., Zhao Y.
<Astron. Astrophys. 686, A230 (2024)>
=2024A&A...686A.230B 2024A&A...686A.230B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, G-type ; Planets ; Radial velocities ; Photometry ; Optical
Keywords: methods: data analysis - planets and satellites: detection -
planets and satellites: gaseous planets -
planets and satellites: general -
planets and satellites: individual: NGTS-30 b -
planets and satellites: individual: TOI-4862 b
Abstract:
Long-period transiting exoplanets bridge the gap between the bulk of
transit- and Doppler-based exoplanet discoveries, providing key
insights into the formation and evolution of planetary systems. The
wider separation between these planets and their host stars results in
the exoplanets typically experiencing less radiation from their host
stars; hence, they should maintain more of their original atmospheres,
which can be probed during transit via transmission spectroscopy.
Although the known population of long-period transiting exoplanets is
relatively sparse, surveys performed by the Transiting Exoplanet
Survey Satellite (TESS) and the Next Generation Transit Survey (NGTS)
are now discovering new exoplanets to fill in this crucial region of
the exoplanetary parameter space.
This study aims to characterise a new long-period transiting exoplanet
by following up on a single-transit candidate found in the TESS
mission.
The TOI-4862 system was monitored using a combination of photometric
instruments (TESS, NGTS, and EulerCam) and spectroscopic instruments
(CORALIE, FEROS, HARPS, and PFS) in order to determine the period,
radius, and mass of the long-period transiting exoplanet NGTS-30
b/TOI-4862 b. These observations were then fitted simultaneously to
determine precise values for the properties and orbital parameters of
the exoplanet, as well as the refined stellar parameters of the host
star.
We present the discovery of a long-period (P=98.29838±0.00010day)
Jupiter-sized (0.928±0.032RJ; 0.960±0.056MJ) planet transiting
a 1.1Gyr old G-type star, one of the youngest warm Jupiters discovered
to date. NGTS-30 b/TOI-4862 b has a moderate eccentricity
(0.294-0.0100.014), meaning that its equilibrium temperature can
be expected to vary from 274-46+30K to 500-84+55K over the
course of its orbit. Through interior modelling, NGTS-30 b/TOI-4862b
was found to have a heavy element mass fraction of 0.23-0.06+0.05
and a heavy element enrichment (Zp/Z*) of 20-6+5, making it
metal-enriched compared to its host star.
NGTS-30 b/TOI-4862 b is one of the youngest well-characterised
long-period exoplanets found to date and will therefore be important
in the quest to understanding the formation and evolution of
exoplanets across the full range of orbital separations and ages.
Description:
This study presents the detection and characterisation of NGTS-30
b/TOI-4862 b, a new long-period transiting exoplanet detected by
following up on a single-transit candidate found in the TESS mission.
Through monitoring using a combination of photometric instruments
(TESS, NGTS, and EulerCam) and spectroscopic instruments (CORALIE,
FEROS, HARPS, and PFS), NGTS-30 b/TOI-4862 b was found to be a
long-period (P=98.3-day) Jupiter-sized (0.928RJ; 0.960MJ) planet
transiting a 1.1Gyr old G-type star. With a moderate eccentricity of
0.294, its equilibrium temperature could be expected to vary from 274
K to 500K over the course of its orbit. Through interior modelling,
NGTS-30 b/TOI-4862 b was found to have a heavy element mass fraction
of 0.23 and a heavy element enrichment (Zp/Zstar) of 20, making it
metal-enriched compared to its host star. NGTS-30 b/TOI-4862 b is one
of the youngest well-characterised long-period exoplanets found to
date and will therefore be important in the quest to understanding the
formation and evolution of exoplanets across the full range of orbital
separations and ages.
Radial velocity measurements of the TOI-4862 system from all
spectroscopic Instruments used in this work. Table includes the time
of observation (in BJD), corrected radial velocity measurement (with
the modelled instrumental offset removed, radial velocity measurement
error and a description of which instrument the measurement was taken
on.
Objects:
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RA (2000) DE Designation(s)
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11 34 51.6 -24 36 19.7 TOI-4862 = TIC 322807371
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 49 68 Radial Velocity measurements of TOI-4862
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 20 F20.12 d BJD Barycentric Julian date
22- 31 F10.6 m/s RV Radial Velocity (1)
33- 41 F9.6 m/s e_RV Radial velocity error
43- 49 A7 --- Inst Name of the instrument
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Note (1): We have shifted the raw radial velocities by their best-fit offset
values from the joint fit to align all data series. To obtain the original
values simply add on the offset values in Table 3 of the paper.
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Acknowledgements:
Matthew Battley, Matthew.battley(at)unige.ch
(End) M. Battley [Geneva Obs., Switzerland], P. Vannier [CDS] 05-Apr-2024