J/A+A/700/A53 Young Moving Groups M dwarfs flare frequency (Mamonova+, 2025)
Flare frequency in M dwarfs belonging to young moving groups.
Mamonova E., Shan Y., Kowalski A.F., Wedemeyer S., Werner S.C.
<Astron. Astrophys. 700, A53 (2025)>
=2025A&A...700A..53M 2025A&A...700A..53M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, M-type ; Stars, pre-main sequence ; Stars, flare ;
Stars, ages ; Stars, masses ; Stars, diameters
Keywords: methods: numerical - planets and satellites: atmospheres -
stars: activity - stars: flare - stars: low-mass -
stars: pre-main sequence
Abstract:
M stars are preferred targets for studying terrestrial exoplanets, for
which we hope to obtain their atmosphere spectra in the next decade.
However, M dwarfs have long been known for strong magnetic activity
and the ability to frequently produce optical, broadband emission
flares. We aim to characterise the flaring behaviour of young M dwarfs
in the temporal, spectral, and energetic dimensions, as well as
examine the stellar parameters governing this behaviour, in order to
improve our understanding of the energy and frequency of the flare
events capable of shaping the exoplanet atmosphere. Young Moving Group
(YMG) members provide a unique age-based perspective on stellar
activity. By examining their flare behaviour in conjunction with
rotation, mass, and Ha data, we obtain a comprehensive understanding
of flare activity drivers in young stars. We demonstrate that young
stars sharing similar stellar parameters can exhibit a variety in
flare frequency distributions and that the flare behaviour shows
indications of difference between optical and far-UV. We propose that
the period of rotation, not the age of the star, can be a good proxy
for assessing flaring activity. Furthermore, we recommend that instead
of a simple power law for describing the flare frequency distribution,
a piecewise power law be used to describe mid-size and large flare
distributions in young and active M dwarfs.Using known periods of
rotation and fine-tuned power law governing the flare frequency, we
can produce a realistic sequence of flare events to study whether the
atmosphere of small exoplanets orbiting M dwarf shall withstand such
activity until life can emerge.
Description:
This data set comprises four tables presenting samples of young (from
YMG) and field M stars, together with their derived stellar
parameters. The tables include rotation periods, mass bins, radii,
Rossby numbers, etc. The samples were assembled to investigate the
temporal and energetic properties of flare activity.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 93 347 YMD subsample main stellar parameters
tablea2.dat 56 133 *CARMENES subsample main stellar parameters
tablea3.dat 149 13 Multi-planet system subsample main stellar
parameters
tablea4.dat 155 493 Sample additional stellar parameters:
activity indicators, magnitudes, distances
refs.dat 68 65 References
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Note on tablea2.dat: data from Shan et al., 2024A&A...684A...9S 2024A&A...684A...9S.
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- ID Star ID
25- 29 A5 --- Group YMG association
31- 35 F5.1 Myr Age Star age if in YMG
37- 42 F6.3 d Prot Rotation period
44- 47 F4.1 --- f_Prot [0/1]? Rotation period flag (1)
49- 51 F3.1 Msun MassBin [1/4] Mass bin (2)
53- 58 F6.4 Rsun Radius Stellar radius
60- 66 A7 --- SpType Spectral type
68- 86 A19 --- r_SpType Reference for spectral type, in refs.dat file
88- 93 F6.3 [-] logRo log10 Rossby number
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Note (1): Flag value as follows:
0 = newly reported
1 = uncertain
blank = denotes values found in this study and in agreement with the literature
Note (2): Bin values as follows:
1 = <0.11
2 = ≥0.11<0.3
3 = ≥0.3<0.45
4 = ≥0.45
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 17 A17 --- ID Star ID
19- 24 A6 --- SpType Spectral type
26- 33 F8.3 d Prot Rotation period
35- 39 F5.1 Myr Age ? Star age
41- 44 F4.2 Rsun Radius Stellar radius
46- 49 F4.2 Msun Mass Stellar mass
51- 56 F6.3 [-] logRo ? log10 Rossby number
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Byte-by-byte Description of file: tablea3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 23 A23 --- ID Star ID
25- 30 F6.1 Myr Age ? Star age
32- 50 A19 --- r_Age Reference for age, in refs.dat file
52- 57 F6.3 d Prot Rotation period
59- 62 F4.1 --- f_Prot [0/1]? Rotation period flag (1)
64- 69 F6.4 Msun Mass Stellar mass
71- 89 A19 --- r_Mass Reference for mass, in refs.dat file
91- 96 F6.4 Rsun Radius Stellar radius
98-116 A19 --- r_Radius Reference for radius
118-122 A5 --- SpType Spectral type
124-142 A19 --- r_SpType Reference for spectral type, in refs.dat file
144-149 F6.3 [-] logRo log10 Rossby number
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Note (1): Flag value as follows:
0 = newly reported
1 = uncertain
blank = denotes values found in this study and in agreement with the literature
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Byte-by-byte Description of file: tablea4.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- ID Star ID
25- 33 E9.7 --- EWHaGaia ? Halpha equivalent width in Gaia DR3
35- 43 F9.6 --- EWHaGaiaMod ? Halpha equivalent width model in Gaia DR3
45- 48 F4.1 --- f_EWHaGaia [0/1]? Halpha equivalent width flag in
Gaia DR3 (1)
50- 58 F9.6 --- e_EWHaGaia ? Error in Halpha equivalent width reported
in Gaia DR3
60- 66 F7.3 --- EWHalit ? Halpha equivalent width in literature
68- 86 A19 --- r_EWHalit ? Reference for Halpha equivalent width,
in refs.dat file
88- 96 F9.6 mag G-RP ? (G-Grp) colour in Gaia DR3
98-106 F9.5 mag Tmag ? TESS T apparent magnitude
108-116 F9.4 pc Dist ? Stellar distance
118-136 A19 --- r_Dist ? Stellar distance reference,
in refs.dat file
138-142 I5 --- FlareCount Number of flares observed
144-155 F12.4 d-1 FlareRate ? Flare rate (2)
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Note (1): Flag value:
0 = model value is not subtracted
1 = model value is subtracted
Note (2): The rate for occurrence of flare with the energy
log10(EKp/TESS)≥31erg.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- BibCode BibCode
21- 46 A26 --- Aut Author's name
48- 68 A21 --- Com Comments
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Acknowledgements:
Elena Mamonova, elena.mamonova(at)geo.uio.no
(End) Patricia Vannier [CDS] 05-Jun-2025