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Solar flare waiting time distribution (WTD). First steps Oscar Olmedo. Outline. Flare waiting distributions What does it model? Power law distribution Sympathetic Flaring. Flares. Boffetta (1999) “Self-Organized Criticality or Turbulence?”
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Solar flare waiting time distribution (WTD) First steps Oscar Olmedo
Outline • Flare waiting distributions • What does it model? • Power law distribution • Sympathetic Flaring
Flares • Boffetta (1999) “Self-Organized Criticality or Turbulence?” • Lu and Hamilton(1991) Magnetic field evolves in a Self organized critical state so flares are an avalanche process. • Or Flares arises from turbulent process. Turbulence shows time intermittency I.e. dissipative events are not uniform but occur in bursts. • Shell model of MHD turbulence correctly reproduce the power law distribution
Flares • Wheatland (2000)”Origin of the solar flare WTD” • Shows Power law originates from an exponential distribution of flaring rates. These results support the avalanche model.
Distribution • Boffetta (1999) • Power law • Wheatland (2000) • Time between flares follows a time varying Poisson distribution. • Distribution of flaring rates is exponential
WTD (Wheatland) Wheatland (2000) Poisson model for flare waiting times. (Right) Flare rates as calculated with Bayesian blocks
Bayesian blocks • Jeffrey Scargle “Studies in astronomical time series analysis. V. Bayesian blocks, a new method to analyze structure in photon counting data.(1998) Each block represent different Poisson rate
Power Law P=Ax-a a=2.1 Wheatland a=2.16 ±0.05 Boffetta a=2.4±0.1
Sympathetic flaring • Pearce and Harrison (1990) • First to show sympathetic flaring • Moon (2002) • Looked at more events