J/AJ/161/171 THYME. V. Discovering a new stellar association (Tofflemire+, 2021)
TESS Hunt for Young and Maturing Exoplanets (THYME).
V. A Sub-Neptune Transiting a Young Star in a Newly Discovered 250Myr
Association.
Tofflemire B.M., Rizzuto A.C., Newton E.R., Kraus A.L., Mann A.W.,
Vanderburg A., Nelson T., Hawkins K., Wood M.L., Zhou G., Quinn S.N.,
Howell S.B., Collins K.A., Schwarz R.P., Stassun K.G., Bouma L.G.,
Essack Z., Osborn H., Boyd P.T., Furesz G., Glidden A., Twicken J.D.,
Wohler B., McLean B., Ricker G.R., Vanderspek R., Latham D.W., Seager S.,
Winn J.N., Jenkins J.M.
<Astron. J., 161, 171 (2021)>
=2021AJ....161..171T 2021AJ....161..171T
ADC_Keywords: Associations, stellar; Photometry, infrared; Optical;
Radial velocities
Keywords: Exoplanet astronomy ; Exoplanets ; Mini Neptunes ; Stellar astronomy ;
Wide binary stars ; Moving clusters ; Stellar ages ; Transits
Abstract:
The detection and characterization of young planetary systems offer a
direct path to study the processes that shape planet evolution. We
report on the discovery of a sub-Neptune-sized planet orbiting the
young star HD110082 (TOI-1098). Transit events we initially detected
during TESS Cycle 1 are validated with time-series photometry from
Spitzer. High-contrast imaging and high-resolution, optical spectra
are also obtained to characterize the stellar host and confirm the
planetary nature of the transits. The host star is a late-F dwarf
(M*=1.2M☉) with a low-mass, M dwarf binary companion
(M*=0.26M☉) separated by nearly one arcminute (∼6200au). Based on
its rapid rotation and Lithium absorption, HD110082 is young, but is
not a member of any known group of young stars (despite proximity to
the Octans association). To measure the age of the system, we search
for coeval, phase-space neighbors and compile a sample of candidate
siblings to compare with the empirical sequences of young clusters and
to apply quantitative age-dating techniques. In doing so, we find that
HD110082 resides in a new young stellar association we designate
MELANGE-1, with an age of 250-70+50Myr. Jointly modeling the TESS
and Spitzer light curves, we measure a planetary orbital period of
10.1827days and radius of Rp=3.2±0.1R⊕. HD110082b's radius
falls in the largest 12% of field-age systems with similar host-star
mass and orbital period. This finding supports previous studies
indicating that young planets have larger radii than their field-age
counterparts.
Description:
Observations took place in Sectors 12 and 13 (2019 May 24 through July
17). During the Transiting Exoplanets Survey Satellite (TESS) extended
mission.
We obtained follow-up observations with the Spitzer Space Telescope to
monitor two transits of HD110082b. These observations occurred on 2019
November 25 and December 5 as part of our time-of-opportunity program
dedicated to young planet-host follow-up (Program ID14011, PI:Newton).
On 2020 May 16, HD110082 was observed for ∼7hr from the Las Cumbres
Observatory Global Telescope (LCOGT) 1.0m network node at the Southern
African Astronomical Observatory (SAAO) in Sutherland, South Africa.
The observation centered temporally on an HD110082b transit, obtaining
Sloan i'-band imaging using the 4096x4096pixel Sinistro CCD imager
(0.39"/pixel).
We have discovered that HD110082 is part of a young stellar
association we designate MELANGE-1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table7.dat 134 133 The HD110082 neighborhood--MELANGE-1 candidates
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See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/305 : The Guide Star Catalog, Version 2.3.2 (GSC2.3) (STScI, 2006)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
II/335 : Revised catalog of GALEX UV sources (GUVcat_AIS GR6+7)(Bianchi+ 2017)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/358 : SkyMapper Southern Sky Survey. DR1.1 (Wolf+, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/A+A/331/81 : Hyades membership (Perryman+ 1998)
J/A+A/367/111 : A Hipparcos study of the Hyades cluster (de Bruijne+, 2001)
J/A+A/460/695 : Search for Associations Containing Young stars (Torres+, 2006)
J/AJ/134/2340 : Membership Praesepe & Coma Berenices clusters (Kraus+, 2007)
J/ApJ/687/1264 : Age estimation for solar-type dwarfs (Mamajek+, 2008)
J/A+A/508/833 : SACY III. Li abundances (da Silva+, 2009)
J/ApJ/699/649 : Young M dwarfs within 25pc. I. (Shkolnik+, 2009)
J/AJ/139/1338 : UV-selected stars in Tau and Upper Sco (Findeisen+, 2010)
J/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010)
J/ApJ/727/125 : Two secondary eclipses of WASP-12b with Spitzer (Campo+,2011)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/MNRAS/413/2218 : Stellar rotation in Hyades and Praesepe (Delorme+, 2011)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
J/ApJ/733/115 : Rotation periods and membership in M34 (Meibom+, 2011)
J/ApJ/756/46 : Lithium abundances in HIP stars (Ramirez+, 2012)
J/ApJ/754/136 : Light curves of HD 149026b in 3.6-16um (Stevenson+, 2012)
J/ApJ/762/88 : Young stellar kinematic group candidate members (Malo+,2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/A+A/560/A4 : Rotation periods of active Kepler stars (Reinhold+, 2013)
J/A+A/568/A26 : SACY. V. Multiple systems (Elliott+, 2014)
J/MNRAS/443/2561 : CONCH-SHELL catalog of nearby M dwarfs (Gaidos+, 2014)
J/AJ/147/146 : Spectroscopy of Tuc-Hor candidate members (Kraus+, 2014)
J/A+A/571/A47 : Extensive linelist CH in stellar atmospheres (Masseron+, 2014)
J/ApJS/211/5 : Improved line data for the Swan system 12C13C (Ram+, 2014)
J/ApJS/214/26 : Line lists for CN isotopes transitions (Sneden+, 2014)
J/A+A/583/A73 : Color-period diagram for M48 (NGC2548) (Barnes+, 2015)
J/ApJ/807/45 : Potent. habitable planets orbiting M dwarfs (Dressing+, 2015)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/MNRAS/447/1267 : Low-mass members of the Octans association (Murphy+, 2015)
J/A+A/588/A103 : 2nd ROSAT all-sky survey (2RXS) source catalog (Boller+, 2016)
J/A+A/590/A13 : New candidate members in young associations (Elliott+, 2016)
J/AJ/152/113 : Pleiades memb. with K2 light curves I. Periods (Rebull+, 2016)
J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+, 2017)
J/A+A/600/A30 : Limb-darkening for TESS satellite (Claret, 2017)
J/AJ/153/128 : WOCS. LXXV. Hyades&Praesepe stellar Li data (Cummings+, 2017)
J/AJ/154/109 : California-Kepler Survey. III. Planet radii (Fulton+, 2017)
J/AJ/154/224 : Transiting planets in young clusters from K2 (Rizzuto+, 2017)
J/AJ/154/69 : ACRONYM II. The β Pictoris Moving Group (Shkolnik+, 2017)
J/MNRAS/474/2094 : Inferring probabilistic stellar rot. periods (Angus+, 2018)
J/ApJ/855/115 : Lithium abundances of KOIs from CKS spectra (Berger+, 2018)
J/A+A/613/A63 : Lithium content for 148 Pleiades stars (Bouvier+, 2018)
J/AJ/156/264 : California-Kepler Survey. VII. Planet rad gap (Fulton+, 2018)
J/ApJ/856/23 : BANYAN. XI. The BANYAN Σ algorithm (Gagne+, 2018)
J/AJ/156/102 : TESS Input Catalog and Candidate Target List (Stassun+, 2018)
J/AJ/156/259 : Robo-AO detected close binaries in Gaia DR2 (Ziegler+, 2018)
J/ApJS/245/13 : CDIPS. I. LCs from TESS sectors 6 and 7 (Bouma+, 2019)
J/ApJ/877/60 : YMGs. I. Young binaries & lithium-rich stars (Bowler+, 2019)
J/ApJ/879/100 : K2 Prot for Hyades & Praesepe members (Douglas+, 2019)
J/MNRAS/482/4570 : Gaia DR2 white dwarf candidates (Gentile Fusillo+, 2019)
J/AJ/157/211 : Unresolved binaries TESS with speckle imaging (Matson+, 2019)
J/A+A/622/L13 : Stellar stream in Gaia DR2 discovery (Meingast+, 2019)
J/MNRAS/490/3806 : Exoplanets & variable stars 47 Tuc field (Nardiello+, 2019)
J/AJ/157/71 : Keck/NIRC2 astrometry for GSC 6214-210 b (Pearce+, 2019)
J/ApJ/877/12 : Coma Ber & a Neighbor Stellar Group tidal tails (Tang+, 2019)
J/AJ/160/239 : Cluster difference imaging photo. survey. II. (Bouma+, 2020)
J/AJ/160/279 : Untangling Galaxy. II. Structure within 3kpc (Kounkel+, 2020)
J/MNRAS/495/4924 : Exoplanets in Southern open clusters (Nardiello+, 2020)
J/ApJS/246/4 : Catalog of ultrawide binary stars from Gaia DR2 (Tian+, 2020)
J/AJ/161/65 : THYME. IV. 3 Exoplanets around TOI-451 B (Newton+, 2021)
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- Gaia Gaia DR2 identifier
21- 28 F8.4 deg RAdeg [0.01/360] Right ascension (J2000)
30- 37 F8.4 deg DEdeg [-90/-74] Declination (J2000)
39- 43 F5.2 mag Gmag [7.91/20.98] Gaia magnitude
45- 48 F4.2 mag Bp-Rp [0/4.2]? Bp-Rp colour
50 A1 --- f_Bp-Rp Flag on Bp-RP (1)
52- 57 F6.3 --- RUWE [0.92/38.9] Renormalized unit weight error
59- 62 F4.2 km/s Voff [0/4.98] Velocity offset
64- 67 F4.1 pc Dist [0/25] Distance
69- 71 F3.1 km/s Vcand [0.6/6.4] Candidate velocity
73- 78 F6.2 km/s RVel [-17.7/56.3]? Radial velocity
80- 83 F4.2 km/s e_RVel [0.06/8.96]? Error on RVel
85 I1 --- r_RVel [1/4]? Reference used for RVel (2)
87 A1 --- l_EWLi Limit flag on LiEW
89- 93 F5.3 0.1nm EWLi [0.02/0.32]? Equivalent width of the lithium Å
95 I1 --- r_EWLi [1/3]? Reference used for EWLi (2)
97-100 F4.1 d Prot [0.1/10]? Rotation period
102 A1 --- f_Prot Flag on Prot (1)
104-108 F5.2 --- fNUV/fJ [0.08/11.5]? Ratio of NUV to J-band flux
density (10-3)
110-114 F5.2 mag W1-W3 [-0.06/0.55]? W1-W3 colour
116-119 F4.2 mag e_W1-W3 [0.02/0.2]? error on W1-W3
121-134 A14 --- Note Additional note
--------------------------------------------------------------------------------
Note (1): Flags as follows:
a = Sibling candidate has a Bp-Rp flux excess error, and is excluded
from our analysis. (27 occurrences)
b = Sibling candidate's rotation-period measurement is preliminary, and
is excluded from our analysis.
Note (2): Reference as follows:
1 = This work
2 = Gaia DR2, 2018, I/345
3 = Torres+, 2006, J/A+A/460/695
4 = Eliott+, 2014, J/A+A/568/A26
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History:
From electronic version of the journal
References:
Newton et al. Paper I. 2019ApJ...880L..17N 2019ApJ...880L..17N
Rizzuto et al. Paper II. 2020AJ....160...33R 2020AJ....160...33R
Mann et al. Paper III. 2020AJ....160..179M 2020AJ....160..179M
Newton et al. Paper IV. 2021AJ....161...65N 2021AJ....161...65N Cat. J/AJ/161/65
Tofflemire et al. Paper V. 2021AJ....161..171T 2021AJ....161..171T This catalog
Mann et al. Paper VI. 2022AJ....163..156M 2022AJ....163..156M Cat. J/AJ/163/156
Newton et al. Paper VII. 2022AJ....164..115N 2022AJ....164..115N Cat. J/AJ/164/115
Barber et al. Paper VIII. 2022AJ....164...88B 2022AJ....164...88B Cat. J/AJ/164/88
Wood et al. Paper IX. 2023AJ....165...85W 2023AJ....165...85W Cat. J/AJ/165/85
Thao et al. Paper X. 2024AJ....168...41T 2024AJ....168...41T Cat. J/AJ/168/41
Capistrant et al. Paper XI. 2024AJ....167...54C 2024AJ....167...54C
(End) Prepared by Coralie Fix [CDS], 10-Sep-2021