J/AJ/160/259 HPF RVs and TESS photometry of TOI-1266 (Stefansson+, 2020)
A Mini-Neptune and a radius valley planet orbiting the nearby M2 dwarf TOI-1266
in its Venus Zone: validation with the Habitable-zone Planet Finder.
Stefansson G., Kopparapu R., Lin A., Mahadevan S., Canas C.I., Kanodia S.,
Ninan J.P., Cochran W.D., Endl M., Hebb L., Wisniewski J., Gupta A.,
Everett M., Bender C.F., Diddams S.A., Ford E.B., Fredrick C., Halverson S.,
Hearty F., Levi E., Maney M., Metcalf A.J., Monson A., Ramsey L.W.,
Robertson P., Roy A., Schwab C., Terrien R.C., Wright J.T.
<Astron. J., 160, 259 (2020)>
=2020AJ....160..259S 2020AJ....160..259S
ADC_Keywords: Exoplanets; Stars, dwarfs; Stars, M-type; Spectra, infrared;
Photometry; Optical; Radial velocities
Keywords: Exoplanets ; Cold Neptunes ; Mini Neptunes ; Super Earths ;
Extrasolar rocky planets ; Exoplanet detection methods ;
Transit photometry
Abstract:
We report on the validation of two planets orbiting the nearby (36pc)
M2 dwarf TOI-1266 observed by the TESS mission. This system is one of
a few M dwarf multiplanet systems with close-in planets where the
inner planet is substantially larger than the outer planet. The inner
planet is sub-Neptune-sized (R=2.46±0.08R⊕) with an orbital
period of 10.9days, while the outer planet has a radius of
1.67-0.11+0.09R⊕ and resides in the exoplanet radius
valley-the transition region between rocky and gaseous planets. With
an orbital period of 18.8days, the outer planet receives an insolation
flux of 2.4 times that of Earth, similar to the insolation of Venus.
Using precision near-infrared radial velocities with the
Habitable-zone Planet Finder Spectrograph, we place upper mass limits
of 15.9 and 6.4M⊕ at 95% confidence for the inner and outer
planet, respectively. A more precise mass constraint of both planets,
achievable with current radial velocity instruments given the host
star brightness (V=12.9, J=9.7), will yield further insights into the
dominant processes sculpting the exoplanet radius valley.
Description:
We obtained high-resolution spectra of TOI-1266 with the Habitable
Planet Finder (HPF) Spectrograph to place upper limits on the masses
of both planets and obtain precise spectroscopic parameters of the
host star. The HPF is a fiber-fed near-infrared (NIR) spectrograph on
the 10m Hobby-Eberly Telescope (HET) at McDonald Observatory in Texas,
covering the z, Y, and J bands from 810 to 1260nm at a resolution of
R=55000.
The Telescope Encoder and Sky Sensor (TESS) observed TOI-1266 in 4
sectors: sector 14 (camera4; 2019 July 18--2019 August 15), sector 15
(camera4; 2019 August 15--2019 September 11), sector 21 (camera3; 2020
January 21--2020 February 18), and sector 22 (camera3; 2020 February
18--2020 March 18).
Objects:
----------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------
13 11 59.18 +65 50 01.31 TOI-1266 = TIC 467179528
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 84 22 HPF radial velocities used in this work
fig2.dat 87 1061 Transit photometry of TOI-1266
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
J/ApJS/200/15 : HARPS-TERRA project. I. (Anglada-Escude+, 2012)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/AJ/145/102 : Spectro. of bright M dwarfs in the northern sky (Lepine+,2013)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/A+A/577/A128 : CARMENES input catalogue of M dwarfs I (Alonso-Floriano+,2015)
J/ApJ/807/45 : Potent. habitable planets orbiting M dwarfs (Dressing+, 2015)
J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+, 2017)
J/AJ/154/109 : California-Kepler Survey III. Planet radii (Fulton+, 2017)
J/ApJ/836/77 : Library of high-S/N optical spectra of FGKM stars (Yee+, 2017)
J/AJ/156/264 : California-Kepler Survey VII Planet radius gap (Fulton+, 2018)
J/AJ/156/102 : TESS Input Catalog and Candidate Target List (Stassun+, 2018)
J/AJ/155/48 : California-Kepler Survey V. Masses and radii (Weiss+, 2018)
J/AJ/157/97 : Radial velocity measurements of K2-3 & GJ3470 (Kosiarek+,2019)
J/ApJ/875/29 : Spectroscopic analysis of the CKS sample. I. (Martinez+, 2019)
J/AJ/159/211 : Exoplanets parameters from Kepler and K2 (Cloutier+, 2020)
J/AJ/160/22 : TOI-1235 RVs & optical spectroscopy (Cloutier+, 2020)
J/ApJS/247/28 : K2 star parameters from Gaia & LAMOST (Hardegree-Ullman+,2020)
J/AJ/159/120 : Transit time of K2-146b & K2-146c with K2 and HPF (Lam+, 2020)
J/AJ/159/100 : Flux & RVs of the dwarf G9-40 with K2 & HPF (Stefansson+,2020)
J/AJ/160/192 : Photometry and RVs of K2-25b with HPF (Stefansson+, 2020)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 F13.5 d BJD [2458854/2459004] Barycentric Julian Date (1)
15- 19 F5.1 m/s RVel [-14.9/17.6] Radial velocity
21- 24 F4.1 m/s e_RVel [5.9/12.5] Uncertainty in RVel
26- 30 F5.1 m2/s2 dLW [-29/69.5] Differential line width indicator
32- 35 F4.1 m2/s2 e_dLW [13.8/29.3] Uncertainty in dLW
37- 42 F6.1 --- CRX [-228/291] Chromatic activity indicator (2)
44- 48 F5.1 --- e_CRX [45.3/213] Uncertainty in CRX
50- 54 F5.3 --- irt1 [0.54/0.57] Line 1 CaII Infrared Triplet line
activity indicator
56- 60 F5.3 --- e_irt1 [0.002/0.004] Uncertainty in irt1
62- 66 F5.3 --- irt2 [0.29/0.31] Line 2 CaII Infrared Triplet line
activity indicator
68- 72 F5.3 --- e_irt2 [0.002/0.004] Uncertainty in irt2
74- 78 F5.3 --- irt3 [0.31/0.34] Line 3 CaII Infrared Triplet line
activity indicator
80- 84 F5.3 --- e_irt3 [0.002/0.004] Uncertainty in irt3
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Note (1): Flux-weighted midpoint of HPF RV observations.
Note (2): In units of m/s/Np, where Np gives the wavelength ratio in Nepers.
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Byte-by-byte Description of file: fig2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Inst Instrument used (TESS)
8- 21 F14.6 d BJD [2458683/2458685] Barycentric Julian Date
23- 30 F8.6 --- Flux [0.99/1.01] Normalized photometric flux with
trend
32- 39 F8.6 --- e_Flux [0.003/0.004] Uncertainty in Flux
41- 48 F8.6 --- trans [0.99/1.001]? Best-fit Transit model (1)
50- 57 F8.6 --- gp [0.99/1.001]? Gaussian-Process red noise
component of best-fit model
59- 66 F8.6 --- FluxDet [0.99/1.01]? Normalized photometric flux after
removing trend with Gaussian Process
68- 75 F8.6 --- TransMod [0.99/1]? Best-fit Transit model; not including
Gaussian Process
77- 87 E11.4 --- Res ? Best-fit residuals
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Note (1): Including transit and Gaussian Process red-noise model.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 09-Feb-2021