J/AJ/165/192 Mdwarfs Ha luminosity & photometric amplitudes (Garcia Soto+, 2023)
Contemporaneous Observations of Hα Luminosities and Photometric Amplitudes
for M Dwarfs.
Garcia Soto A., Newton E.R., Douglas S.T., Burrows A., Kesseli A.Y.
<Astron. J., 165, 192 (2023)>
=2023AJ....165..192G 2023AJ....165..192G
ADC_Keywords: Stars, M-type; Photometry, H-alpha; Optical; Stars, masses;
Stars, diameters; Parallaxes, trigonometric
Keywords: Stellar activity ; Low mass stars ; Stellar rotation ; Stellar
spectral lines
Abstract:
While many M-dwarfs are known to have strong magnetic fields and high
levels of magnetic activity, we are still unsure about the properties
of their starspots and the origin of their magnetic dynamos. Both
starspots and chromospheric heating are generated by the surface
magnetic field; they produce photometric variability and Hα
emission, respectively. Connecting brightness variations to magnetic
activity therefore provides a means to examine M-dwarf magnetism. We
survey 30M dwarfs previously identified as fast rotating stars
(Prot<10days). We present time-series optical photometry from the
Transiting Exoplanet Survey Satellite (TESS) and contemporaneous
optical spectra obtained using the Ohio State Multi-Object
Spectrograph (OSMOS) on the 2.4m Hiltner telescope at MDM Observatory
in Arizona. We measure rotation periods and photometric amplitudes
from TESS light curves using Gaussian Processes. From the OSMOS
spectra, we calculate the equivalent width of Hα, and
LHα/Lbol. We find a weak positive correlation between Hα
luminosity and the semiamplitude, Rvar (p=0.005-0.005+0.075). We
also observe short-term variability (between 20 and 45minutes) in
Hα equivalent widths and possible enhancement from flares
consistent to recent literature.
Description:
TESS data products include 30minute cadence full frame images and
2minute cadence "postage stamp" images of selected stars. The Science
Processing Operations Center produces 2minute cadence light curves
FITS files, which are then released to the public via Mikulski Archive
for Space Telescopes archive.
We observe Hα emission using (Ohio State Multi-Object
Spectrograph) OSMOS, mounted on the 2.4m Hiltner telescope at MDM
Observatory in Arizona. Our setup consists of the blue VPH grism with
a inner 1.2" slit and a 4x1k region of interest. The resulting spectra
span 390-680nm, with peak efficiency around 640nm and a R∼600
resolution. In this configuration, OSMOS is well-suited to
single-object spectroscopy, particularly for our study of Hα
emission at around 656.21nm.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 227 33 Parameters for some M-dwarfs in our sample
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
VI/156 : M-dwarf Lum-Temp-Radius relationships (Morrell+, 2019)
J/A+A/327/1039 : Structure and evolution of low-mass stars (Chabrier+ 1997)
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
J/A+A/394/505 : UBV photometry of LQ Hya (Berdyugina+, 2002)
J/AJ/123/3356 : Palomar/MSU nearby star spectro survey. III. (Gizis+, 2002)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/MNRAS/390/545 : Magnetic field and velocity of early M dwarfs (Donati+, 2008)
J/ApJ/687/1264 : Age estimation for solar-type dwarfs (Mamajek+, 2008)
J/MNRAS/390/567 : Magnetic field and velocity of mid M dwarfs (Morin+, 2008)
J/MNRAS/407/2269 : Polarisation of a sample of late M dwarfs (Morin+, 2010)
J/AJ/141/166 : HATNet variability survey of K and M dwarfs (Hartman+, 2011)
J/ApJ/728/48 : Multicolor eclipse data for 6 new binaries (Kraus+, 2011)
J/AJ/141/97 : SDSS DR7 M dwarfs (West+, 2011)
J/ApJ/743/48 : Star with rotation periods & Xray luminosities (Wright+, 2011)
J/MNRAS/423/2966 : Low-mass stars spectroscopy in NGC 2516 (Jackson+, 2012)
J/AcA/62/67 : ASAS photometry of ROSAT sources (Kiraga, 2012)
J/AJ/143/93 : Rotational velocities in early-M stars (Reiners+, 2012)
J/AcA/63/53 : ASAS photometry of ROSAT sources. II. (Kiraga+, 2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/ApJ/795/161 : Activity & rotation in Praesepe & the Hyades (Douglas+, 2014)
J/MNRAS/441/2361 : Stellar magnetism, age and rotation (Vidotto+, 2014)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/829/23 : Stellar flares from Q0-Q17 Kepler LCs (Davenport, 2016)
J/ApJ/821/93 : Rotation & Galactic kinematics of mid M dwarfs (Newton+, 2016)
J/A+A/597/A47 : CARMENES input catalogue of MdwarfsII (Cortes-Contreras+ 2017)
J/ApJ/837/96 : Rotation-Activity Corr. in KMdwarfs II. (Houdebine+, 2017)
J/ApJ/834/85 : Hα emission in nearby M dwarfs (Newton+, 2017)
J/MNRAS/474/2094 : Inferring probabilistic stellar rot periods (Angus+, 2018)
J/MNRAS/475/1960 : ESPaDOnS spectropolarimeter obs. of M dwarfs (Fouque+, 2018)
J/AJ/155/225 : Mdwarf rotational broadening measurements (Kesseli+, 2018)
J/ApJ/855/75 : 24 years monitoring of Sun and Sun-like stars (Radick+, 2018)
J/A+A/612/A49 : 324 CARMENES M dwarfs velocities (Reiners+, 2018)
J/AJ/156/102 : TESS Input Catalog and Candidate Target List (Stassun+, 2018)
J/AJ/156/178 : NIR transmission spectra of TRAPPIST-1 planets (Zhang+, 2018)
J/ApJ/871/63 : How to constrain Mdwarf. II. Nearby binaries (Mann+, 2019)
J/AJ/157/216 : Stellar multiplicity of Mdwarfs within 25pc (Winters+, 2019)
J/MNRAS/495/2949 : Stellar activity with LAMOST. III. (Fang+, 2020)
J/A+A/638/A20 : Mdwarfs Xray activity and rotation relations (Magaudda+, 2020)
J/ApJ/905/107 : Spectroscopic activity indicators of TIC stars (Medina+, 2020)
J/AJ/161/36 : 117 exoplanets habitable zone with Kepler DR25 (Bryson+, 2021)
J/AJ/161/63 : Mdwarfs masses 0.1≲M/M☉≲0.3 within 15pc (Winters+, 2021)
J/AJ/164/115 : TESS Hunt for Young & Maturing Exoplanets VII. (Newton+, 2022)
J/A+A/662/A41 : Magnetic fields in 292 M dwarfs. (Reiners+, 2022)
J/ApJS/264/17 : Spectroscopic data of TESS objects with LAMOST (Zhang+, 2023)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- TIC TESS identifier
11- 27 A17 --- 2MASS 2MASS position based identifier
29- 34 F6.4 Msun Mass [0.09/0.42] Target's mass (1)
36- 41 F6.4 Msun e_Mass [0/0.01] Errors on mass (1)
43- 48 F6.4 Rsun Rad [0.12/0.43] Target radius (2)
50- 55 F6.4 Rsun e_Rad [0/0.02] Lower bound error on radius (2)
57- 62 F6.4 Rsun E_Rad [0/0.02] Upper bound: error on radius (2)
64- 70 F7.4 km/s vsini [3.6/66] vsini measurements from literature
72- 77 F6.4 km/s e_vsini [0.2/3.5] error on vsini
79 I1 --- r_vsini References for the vsini measurements
81- 87 F7.4 deg i [17.4/88.8] Target inclination (4)
89- 95 F7.4 deg e_i [0.8/19] Errors on inclination
97-102 F6.4 d Prot [0.11/7.75] Rotational periods (5)
104-109 F6.4 d e_Prot [0/0.2] Lower Bound: error on period
111-116 F6.4 d E_Prot [0/0.2] Upper Bound: error on period
118-125 F8.6 d LitProt [0.11/7.78] Fiducial rotational periods from
the literature
127-128 I2 --- r_LitProt References for LitProt (3)
130-135 F6.4 --- Rvar [0/0.03] Photometric amplitudes measurements
(6)
137-142 F6.4 --- e_Rvar [0/0.01] Lower Bound: error on Rvar
144-149 F6.4 --- E_Rvar [0/0.01] Upper Bound: error on Rvar
151-158 F8.4 0.1nm EWHa [-12.6/-2.83] Mean target Halpha
Equivalent Widths (7)
160-165 F6.4 --- LHa/Lbol [0/0.01] Fractional Halpha
luminosity/bolometric luminosity
(derived from color)
167-173 F7.4 mag Tmag [8.33/13.9] T-magnitude from TESS
175-181 F7.4 mag Ksmag [5.69/10.9] Ks-magnitude from 2MASS
183-188 F6.4 mas plx [0.03/0.28] Parallax from Gaia (DR2 or DR3),
rounded
190-195 F6.4 mas e_plx [0/0.01] Errors on plx
197-202 F6.4 --- RUWE [0.95/1.58] RUWE value from Gaia
204-209 F6.4 --- TESS-CR [0/0.14] TESS Contamination Ratio value
from MAST
211-216 A6 --- SpT Spectral Types from SIMBAD
218-220 A3 "month" Obs.M Observation month (8)
222-223 I2 yr Obs.Y [19/21] Year of observation (8)
225-227 A3 --- Flags Flare removal flags (9)
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Note (1): Masses derived using posterial distribution/the M-MK- code
(https://github.com/awmann/M_-M_K-) from Mann+, 2019, J/ApJ/871/63
with the errors using as the confidence interval of the posterior
distribution.
Note (2): Radii derived using equation 4 in Mann+, 2015, J/ApJ/804/64
with errors using MCMC and incorporating rms.
Note (3): References as follows:
1 = Reiners+, 2018 J/A+A/612/A49
2 = Kesseli+, 2018, J/AJ/155/225
3 = Fouque+, 2018, J/MNRAS/475/1960
4 = Newton+, 2016, J/ApJ/821/93
5 = Hartman+, 2011, J/AJ/141/166
6 = Kiraga+, 2012, J/AcA/62/67
7 = Alekseev+, 1998ARep...42..655A 1998ARep...42..655A
8 = Morin+, 2008MNRAS.384...77M 2008MNRAS.384...77M
9 = Medina+, 2022ApJ...928..185M 2022ApJ...928..185M
10 = Kiraga+, 2013, J/AcA/63/53
Note (4): Inclination derived using code from Vanderburg+,
2021zndo...5599854V, following Masuda & Winn, 2020AJ....159...81M 2020AJ....159...81M with
errors using MCMC from Vanderburg+, 2021, https://zenodo.org/record/5599854
Note (5): Rotational periods derived from Gaussian Process via Agnus
& Garcia Soto, 2023, [doi:10.5281/ZENODO.7697238] and errors
using the PyMC3 package, Salvatier+, 2016, [doi:10.7717/peerj-cs.55].
Note (6): Photometric amplitudes, Rvar measurements with errors
derived using MCMC.
Note (7): Mean target Halpha Equivalent Widths using ernlib,
https://github.com/ernewton/ernlib
Note (8): Three TIDs have two rows because they were observed twice.
Note (9): Flags as follows:
c = Needed manual flare removal on the edges after stellar
d = Needed jitter term toggled on
e = Needed both the jitter and the trend term toggled on
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 19-Sep-2023