J/AJ/164/223 209 flares observed in 69 stars with CoRoT (Rabello Soares+, 2022)
Blackbody Temperature of 200+ Stellar Flares Observed with the CoRoT Satellite.
Rabello Soares M.C., de Freitas M.C., Ferreira B.P.L.
<Astron. J., 164, 223 (2022)>
=2022AJ....164..223R 2022AJ....164..223R
ADC_Keywords: Stars, flare; Optical; Spectral types; Cross identifications
Keywords: Stellar flares ; Optical flares ; Astrostatistics ; Artificial
satellites ; Stellar rotation ; Stellar properties
Abstract:
We estimated blackbody temperature for 209 flares observed at 69 F-K
stars, significantly increasing the number of flare temperature
determinations. We used the Blue and Red channels obtained by the 27cm
telescope of the CoRoT satellite at high cadence and long duration.
The wavelength limits of the channels were estimated using spectra
from the Pickles library for the spectral type and luminosity class of
each star, provided by the Exodat Database. The temperatures were
obtained from the flare energy Blue-to-Red ratio, using the flare
equivalent duration and stellar flux in both channels. The expected
value of the analyzed flares is equal to 6400K with a standard
deviation of 2800K, where the mean stellar spectral type, weighted by
the number of flares in each spectral subclass, is equal to G6.
Contrary to our results, a stellar white-light flare is often assumed
to emit as a blackbody with a temperature of 9000 or 10000K. Our
estimates agree, however, with values obtained for solar flares. The
GAIA G-band transmissivity is comparable to that of the CoRoT White
channel, which allows us to calibrate the flares to the Gaia
photometric system. The energy in the G band of the analyzed flares
varies between 1032 and 1037erg, and the flare area ranges from
30µsh to 3sh (solar hemisphere). The energy release per area in a
flare is proportional to Tflare2.6, at least up to 10000K.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 85 209 Flare catalog for the 69 flaring stars analyzed
table3.dat 32 69 EDR3 Gaia identification used for each analyzed
CoRoT star
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See also:
B/corot : CoRoT observation log (N2-4.4) (CoRoT 2016)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/PASP/110/863 : A Stellar Spectral Flux Library; 1150 - 25000 A (Pickles 1998)
J/A+A/520/A66 : CoRoT-8b light and RV curves (Borde+, 2010)
J/A+A/538/A112 : Planetary transit candidates in CoRoT LRa01 (Carone+, 2012)
J/other/Nat/485.478 : Superflares on solar-type stars (Maehara+, 2012)
J/ApJS/207/15 : M dwarf flare spectra (Kowalski+, 2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/ApJS/209/5 : Superflares of Kepler stars. I. (Shibayama+, 2013)
J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)
J/A+A/581/A66 : UV variability and accretion in NGC 2264 (Venuti+, 2015)
J/A+A/602/A117 : Periods of 2290 CoRoT binaries (Klagyivik+, 2017)
J/ApJ/851/91 : Statistical studies solar white-light flares (Namekata+, 2017)
J/A+A/619/A97 : CoRoT transit catalogue (Deleuil+, 2018)
J/AJ/159/60 : 8695 flares 1228 stars in TESS sectors 1 & 2 (Gunther+, 2020)
J/ApJ/902/115 : EvryFlare. III. Superflares Evryscope & TESS (Howard+, 2020)
J/ApJ/907/89 : Starspots's temperature & area 337 KIC stars (Herbst+, 2021)
J/ApJ/906/72 : 2344 superflares on 266 solar-type stars (Okamoto+, 2021)
J/A+A/649/A3 : Gaia Early Data Release3 photometric passbands (Riello+, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- CoRoT CoRoT identifier
11- 15 A5 --- SpT Spectral type, Exodat database
17- 23 F7.4 d Prot [0.41/47]? Rotation period, days
25- 31 F7.4 d e_Prot [0.0004/11]? Uncertainty in Prot
33- 35 A3 --- f_Prot [abtd, ] Flag(s) on Prot (1)
37- 41 F5.2 10+3K Tflare [3.19/37] Flare temperature
43- 47 F5.2 10+3K e_Tflare [0.3/10] Uncertainty in Tflare
49- 49 A1 --- f_Tflare [*] Flag on Tflare (2)
51- 59 A9 10-7J Egf Gaia flare energy, ergs
61- 67 A7 10-7J e_Egf Uncertainty in Egf
69- 77 A9 cm2 Aflare Flare area
79- 85 A7 cm2 e_Aflare Uncertainty in Aflare
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Note (1): Flags as follows:
a = an eclipsing binary identified by Deleuil+, 2018, J/A+A/619/A97
b = an eclipsing binary identified by Klagyivik+, 2017, J/A+A/602/A17
t = a T Tauri analysed by Venuti+, 2015, J/A+A/581/A66
d = In the case of the eclipsing binary CoRoT 102615551, the Prot was
obtained by Deleuil+, 2018, J/A+A/619/A97.
Note (2): Flag as follows:
* = Flares observed at different epochs (taken ∼4 years apart).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- CoRoT CoRoT ID
11- 29 I19 --- Gaia Gaia EDR3 ID
31- 32 A2 --- Flag Flag (1)
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Note (1): Flags as follows:
R2 = The EDR3 Gaia observation corresponding to CoRoT 102379742 does not
have an estimated parallax, and has been replaced by Gaia DR2;
d = The three EDR3 Gaia observations that are more than one arcsec away
from the CoRoT target;
F = The two EDR3 Gaia observations that are fainter than expected.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 06-Dec-2022