J/AJ/168/67 TOI-1450 radial velocities & activity indicators (Brady+, 2024)
Early results from the HUMDRUM survey: a small, Earth-mass planet orbits
TOI-1450A.
Brady M., Bean J.L., Seifahrt A., Kasper D., Luque R., Stefansson G.,
Sturmer J., Charbonneau D., Collins K.A., Doty J.P., Essack Z., Fukui A.,
Grau Horta F., Hedges C., Hellier C., Jenkins J.M., Narita N., Quinn S.N.,
Shporer A., Schwarz R.P., Seager S., Stassun K.G., Striegel S.,
Watkins C.N., Winn J.N., Zambelli R.
<Astron. J., 168, 67 (2024)>
=2024AJ....168...67B 2024AJ....168...67B
ADC_Keywords: Stars, M-type; Spectra, optical; Radial velocities;
Stars, double and multiple; Exoplanets
Keywords: M dwarf stars ; Extrasolar rocky planets
Abstract:
M-dwarf stars provide us with an ideal opportunity to study nearby
small planets. The HUnting for M Dwarf Rocky planets Using MAROON-X
(HUMDRUM) survey uses the MAROON-X spectrograph, which is ideally
suited to studying these stars, to measure precise masses of a
volume-limited (<30pc) sample of transiting M-dwarf planets. TOI-1450
is a nearby (22.5pc) binary system containing a M3 dwarf with a
roughly 3000K companion. Its primary star, TOI-1450A, was identified
by the Transiting Exoplanet Survey Satellite (TESS) to have a 2.04d
transit signal, and is included in the HUMDRUM sample. In this paper,
we present MAROON-X radial velocities (RVs) which confirm the
planetary nature of this signal and measure its mass at nearly 10%
precision. The 2.04d planet, TOI-1450A b, has Rb=1.13±0.04R⊕
and Mb=1.26±0.13M⊕. It is the second-lowest-mass transiting
planet with a high-precision RV mass measurement. With this mass and
radius, the planet's mean density is compatible with an Earth-like
composition. Given its short orbital period and slightly sub-Earth
density, it may be amenable to JWST follow-up to test whether the
planet has retained an atmosphere despite extreme heating from the
nearby star. We also discover a nontransiting planet in the system
with a period of 5.07 days and a Msinic=1.53±0.18M⊕. We
also find a 2.01 days signal present in the systems's TESS photometry
that likely corresponds to the rotation period of TOI-1450A's binary
companion, TOI-1450B. TOI-1450A, meanwhile, appears to have a rotation
period of approximately 40 days, which is in line with our
expectations for a mid-M dwarf.
Description:
MAROON-X is a high-precision echelle spectrograph mounted on the 8.1m
telescope Gemini-North. It has a wavelength coverage in the visible
and near-infrared encompassing 500-920nm. The instrument has two CCDs,
one "blue" (500-670nm) and the other "red" (650-920nm), which are both
exposed simultaneously whenever a target is observed.
We observed TOI-1450A as a part of the HUnting for M Dwarf Rocky
planets Using MAROON-X (HUMDRUM) sample, observing the system
118 times between the months of 2021 April and 2023 July. As the
planet has an orbital period very close to 2 days, we attempted to
observe it multiple times a night to improve our phase coverage.
The data are shown in Figure 1. Our RVs are included in Table 2.
See Section 3.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
19 07 24.83 +59 05 09.3 TOI-1450A = WDS J19074+5905A
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 62 236 MAROON-X RVs and activity indicators
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
VII/233 : 2MASS All-Sky Extended Source Catalog (XSC) (IPAC/UMass, 2003-2006)
J/ApJS/197/8 : Kepler's cand. multiple transiting planets (Lissauer+, 2011)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/AJ/145/102 : Sp. of bright M dwarfs in the northern sky (Lepine+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/809/77 : Transiting Exoplanet Survey Satellite (TESS) (Sullivan+, 2015)
J/A+A/588/A103 : 2nd ROSAT all-sky survey (2RXS) source catalog (Boller+, 2016)
J/AJ/152/180 : Bol. fluxes of eclipsing binaries in Tycho-2 (Stassun+, 2016)
J/AJ/154/109 : California-Kepler Survey (CKS). III. Radii (Fulton+, 2017)
J/AJ/153/136 : Planets and their host stars with Gaia plx (Stassun+, 2017)
J/AJ/155/180 : A catalog of cool dwarf targets for the TESS (Muirhead+, 2018)
J/A+A/615/A6 : Photospheric parameters of CARMENES stars (Passegger+, 2018)
J/AJ/155/48 : California-Kepler Survey (CKS). V. Masses (Weiss+, 2018)
J/ApJ/871/63 : How to constrain your M dwarf. II. Nearby bin. (Mann+, 2019)
J/A+A/624/A49 : Sp. of Earth-like planets around M-dwarfs (Wunderlich+, 2019)
J/ApJS/250/20 : Rot. periods in TESS objects of interest (TOIs) (Canto+, 2020)
J/A+A/636/L6 : HD 158259 SOPHIE radial velocities (Hara+, 2020)
J/AN/341/996 : Stellar companions of (C)TOIs (Mugrauer+, 2020)
J/ApJS/254/39 : Exoplanet candidates from TESS first 2yr obs (Guerrero+, 2021)
J/ApJ/916/77 : K2 rot. periods for SDSS & Gaia M dwarfs (Popinchalk+, 2021)
J/A+A/664/A105 : Stellar content of the ROSAT all-sky survey (Freund+, 2022)
J/other/Sci/377.1211 : RV and LC of 8 M dwarf stars with planets (Luque+, 2022)
J/A+A/658/A194 : Stellar parameters of 18 M dwarfs (Passegger+, 2022)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.5 d BTJD [2321.07/3136.03] Barycentric Julian Date;
BTJD-2457000
12- 15 A4 --- Channel MAROON-X channel ("blue" or "red")
17- 21 A5 --- Run MAROON-X run (MMMYY)
23- 28 F6.2 m/s RV [-11.7/9.1] Radial velocity
30- 33 F4.2 m/s e_RV [0.27/2.01] Uncertainty in RV
35- 40 F6.2 --- CRX [-71/59] Chromatic index spectroscopic
activity indicator in m/s/Np
42- 46 F5.2 --- e_CRX [3.2/41.8] Uncertainty in CRX in m/s/Np
48- 54 F7.5 --- Ha [0.556/0.689] Hα index spectroscopic
activity indicator
56- 62 F7.5 --- e_Ha [0.0013/0.007] Uncertainty in Ha
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 01-Oct-2024