Difference between revisions of "Triggers:Flares"

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Statistical study of M dwarf flares in Stripe 82 is presented in [http://arxiv.org/abs/0906.2030 Kowalski et al. 2009].
 
Statistical study of M dwarf flares in Stripe 82 is presented in [http://arxiv.org/abs/0906.2030 Kowalski et al. 2009].
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Kepler M and K flares are analysed in [http://arxiv.org/abs/1008.0853 Walkowicz et al. 2011].
  
 
[[File:Flare_example_Stripe82.png|400px|right]]
 
[[File:Flare_example_Stripe82.png|400px|right]]
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== Light curve examples ==  
 
== Light curve examples ==  
  
[[File:Mdwarf_flare_Gl234AB.png|600px]] Example of flares in Gl234AB (V577 Mon) from [http://ukads.nottingham.ac.uk/abs/1989A%26A...208..208D Doyle et al. 1989]
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[[File:uv_ceti.png|thumb|550px|border|left|High temporal resolution observations of a flare from UV Cet star. From [http://adsabs.harvard.edu/abs/1973ApJ...185..239B Bopp & Moffett 1973.]]]
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[[File:yzcmi.png|thumb|450px|border|right|The YZ Cmi U-band flare. From [http://adsabs.harvard.edu/abs/2010ApJ...714L..98K Kowalski 2010]]]
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[[File:cn_leo.png|thumb|350px|border|left|Outburst of the flare star CN Leo. From [http://arxiv.org/abs/0810.1179 Sokolowski 2008].]]
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[[File:gj3332.png|thumb|450px|border|center|High temporal resolution observations of a flare star by Pi of the Sky. From [http://arxiv.org/abs/0810.1179 Sokolowski 2008].]]
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[[File:FlareCNLeo-PioftheSky.png|400px]] Example flare detected by Pi of the Sky project. From [http://arxiv.org/abs/0810.1179 Sokolowski 2008].
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== Spectrum examples ==
  
[[File:cn_leo.png|thumb|400px|border|left|Outburst of the flare star CN Leo. From [http://arxiv.org/abs/0810.1179 Sokolowski 2008].]]
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[[File:yzcmi_spec.png|thumb|450px|border|left|Example of a flare spectrum with an excess of radiation at short wavelengths and pronounced Balmer emission lines. From [http://adsabs.harvard.edu/abs/2010ApJ...714L..98K Kowalski 2010].]]
  
[[File:gj3332.png|thumb|400px|border|right|High temporal resolution observations of a flare star by Pi of the Sky. From [http://arxiv.org/abs/0810.1179 Sokolowski 2008].]]
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[[File:M_star_spectrum.png|thumb|450px|border|center|Spectrum of an M6 dwarf is extremely red. From [http://cas.sdss.org/dr7/en/tools/chart/navi.asp?ra=194.4769&dec=3.55015 SDSS DR7]]]

Latest revision as of 10:46, 3 October 2011

M dwarf flares

Statistical study of M dwarf flares in Stripe 82 is presented in Kowalski et al. 2009.

Kepler M and K flares are analysed in Walkowicz et al. 2011.

Flare example Stripe82.png
  • Colour range for M-dwarfs (r − i) > 0.53 and (i − z) > 0.3 and (u-r) > 3
  • The most flaring are late type M-dwarfs (M4-M6), earlier types (M2-M3) flare half as often as late types and M0-M1 dwarfs flare only 20% as often as late types.
  • flares are the most pronounced in u-band
  • around 35% of M-dwarfs are in binary systems - these have bluer u-g. Most single M-dwarfs will have u-g > 1.8
  • g - K > 4 - significantly brighter in IR (2MASS cross-match) than Visual.
  • amplitude in u > 0.7 mag up to 5 mag.
  • large and small flares possible on the same star
  • flaring fraction: 0.0108%, i.e. 1 of every 10,000 observation of a M-dwarf in Stripe 82 resulted in a flare
  • Sloan (5yrs) flaring star probabilities for different types of Mdwarf: M0-M1: 38/35,000; M2-M3: 79/13,000; M4-M6: 119/2120.
  • 1.3 flares per hour sq.deg with <math>\Delta u > 0.7</math> mag, with slightly more flares towards the galactic plane.
Mflares-rates.png

Ampitude distribution for Stripe82 flares.

Light curve examples

High temporal resolution observations of a flare from UV Cet star. From Bopp & Moffett 1973.
The YZ Cmi U-band flare. From Kowalski 2010
Outburst of the flare star CN Leo. From Sokolowski 2008.
High temporal resolution observations of a flare star by Pi of the Sky. From Sokolowski 2008.


Spectrum examples

Example of a flare spectrum with an excess of radiation at short wavelengths and pronounced Balmer emission lines. From Kowalski 2010.
Spectrum of an M6 dwarf is extremely red. From SDSS DR7