J/A+A/650/A138 TRAPPIST-1 analogue stars TESS light curves (Seli+, 2021) ================================================================================ Activity of TRAPPIST-1 analog stars observed with TESS. Seli B., Vida K., Moor A., Pal A., Olah K. =2021A&A...650A.138S (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Stars, M-type ; Photometry ; Optical ; Stars, ages ; Keywords: stars: activity - stars: flare - stars: late-type - stars: low-mass - starspots - stars: statistics Abstract: As more exoplanets are being discovered around ultracool dwarfs, understanding their magnetic activity - and the implications for habitability - is of prime importance. To find stellar flares and photometric signatures related to starspots, continuous monitoring is necessary, which can be achieved with spaceborn observatories like the Transiting Exoplanet Survey Satellite (TESS). We present an analysis of TRAPPIST-1 like ultracool dwarfs with TESS full- frame image photometry from the first two years of the primary mission. A volume-limited sample up to 50pc is constructed consisting of 339 stars closer than 0.5mag to TRAPPIST-1 on the Gaia colour-magnitude diagram. The 30-min cadence TESS light curves of 248 stars were analysed, searching for flares and rotational modulation caused by starspots. The composite flare frequency distribution of the 94 identified flares shows a power law index similar to TRAPPIST-1, and contains flares up to E_TESS_=3*10^33^erg. Rotational periods shorter than 5 days were determined for 42 stars, sampling the regime of fast rotators. The ages of 88 stars from the sample were estimated using kinematic information. A weak correlation between rotational period and age is observed, which is consistent with magnetic braking. Description: We present the catalogue of TRAPPIST-1 analogue stars, and also the additional tables with the detected rotational periods,flares, and comoving pair candidates. The individual TESS FFI light curves are also available, these are the final light curves after PCA detrending. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table2.dat 139 339 The TRAPPIST-1 analogue sample tablea1.dat 57 42 Rotational periods from the Lomb-Scargle analysis tableb1.dat 90 94 Flare parameters tablec1.dat 74 20 Comoving pair candidates from Gaia DR2 phot.dat 60 370 List of light curve files for 240 Gaia DR2 sources of table2 lc/* . 370 Individual light curves -------------------------------------------------------------------------------- See also: I/345 : Gaia DR2 (Gaia Collaboration, 2018) Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 I19 --- GaiaDR2 Gaia DR2 source_id 21- 30 I10 --- TIC ? TESS Input Catalog ID 32- 36 F5.2 mag BPmag ? Gaia BP magnitude 38- 42 F5.2 mag RPmag ? Gaia RP magnitude 44- 48 F5.2 pc Dist ? Distance 50- 53 F4.2 pc e_Dist ? Uncertainty of distance 55- 89 A35 --- TESS-Sectors Comma separated TESS sectors where the target was observed 91- 94 F4.1 0.1nm EWHa ? H{alpha} equivalent width 96- 99 F4.1 0.1nm e_EWHa ? Uncertainty of H{alpha} equivalent width 101-104 F4.1 Gyr Age ? Age 106-108 F3.1 Gyr e_Age ? Uncertainty of Age 110-139 A30 --- Comm Comment on age -------------------------------------------------------------------------------- Byte-by-byte Description of file: tablea1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 I19 --- GaiaDR2 Gaia DR2 source_id 21- 27 F7.5 d Per [0.1/4.92] rotational period 29- 35 F7.5 d e_Per Uncertainty of the rotational period 37- 44 E8.2 --- FAP False alarm probability 46- 49 F4.1 mmag Ampl [0.9/34.8] amplitude 51- 54 F4.1 mmag Scatter [2.8/54.1] scatter 56- 57 I2 --- Nflares [0/10] number of flares -------------------------------------------------------------------------------- Byte-by-byte Description of file: tableb1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 I19 --- GaiaDR2 Gaia DR2 source_id 21- 31 F11.3 d Tpeak ? Fitted Julian time of the flare peak 33- 37 F5.3 d e_Tpeak ? Uncertainty of the fitted time of the flare peak 39- 42 F4.1 min t12 ? Fitted half-time of the flare 44- 48 F5.1 min e_t12 ? Uncertainty of the fitted half-time of the flare 50- 54 F5.2 --- Ampl ? Fitted amplitude of the flare 56- 59 F4.2 --- e_Ampl ? Uncertainty of the fitted amplitude of the flare 61- 65 F5.1 min EDfit ? Equivalent duration from fitted parameters 67- 70 F4.1 min e_EDfit ? Uncertainty of the equivalent duration from fitted parameters 72- 76 F5.1 min EDsum ? Equivalent duration from integrated flux 78- 80 F3.1 min e_EDsum ? Uncertainty of the equivalent duration from integrated flux 82- 86 F5.1 10+34W Esum ? Flare energy in 10^31^erg from EDsum 88- 90 F3.1 10+34W e_Esum ? Uncertainty of the flare energy in 10^31^erg from EDsum -------------------------------------------------------------------------------- Byte-by-byte Description of file: tablec1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 I19 --- Target Gaia DR2 source_id of the target 21- 39 I19 --- Comp Gaia DR2 source_id of the companion 41- 44 I4 AU Sep [60/9970]? Separation 46- 48 F3.1 Gyr Age ? Kinematic age 50- 52 F3.1 Gyr e_Age ? Kinematic age uncertainty 54- 74 A21 --- Comm Comment on the companion -------------------------------------------------------------------------------- Byte-by-byte Description of file: phot.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 I19 --- GaiaDR2 Gaia DR2 source_id 21- 22 I2 --- TESS-Sector [1/26] TESS sector 24- 60 A37 --- FileName Filename, in subdirectory lc -------------------------------------------------------------------------------- Byte-by-byte Description of file: lc/* -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 14 F14.6 d JD Julian date 16- 25 F10.6 mag mag TESS differential magnitude 27- 35 F9.6 mag e_mag TESS magnitude uncertainty -------------------------------------------------------------------------------- Acknowledgements: Balint Seli, seli.balint(at)csfk.org ================================================================================ (End) Patricia Vannier [CDS] 30-Mar-2021