The Origin of the Solar Flare Waiting-Time Distribution
Abstract
It was recently pointed out that the distribution of times between solar flares (the flare waiting-time distribution) follows a power law for long waiting times. Based on 25 years of soft X-ray flares observed by Geostationary Operational Environmental Satellite instruments, it is shown that (1) the waiting-time distribution of flares is consistent with a time-dependent Poisson process and (2) the fraction of time the Sun spends with different flaring rates approximately follows an exponential distribution. The second result is a new phenomenological law for flares. It is shown analytically how the observed power-law behavior of the waiting times originates in the exponential distribution of flaring rates. These results are argued to be consistent with a nonstationary avalanche model for flares.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 2000
- DOI:
- 10.1086/312739
- arXiv:
- arXiv:astro-ph/0005121
- Bibcode:
- 2000ApJ...536L.109W
- Keywords:
-
- Magnetohydrodynamics: MHD;
- Sun: Activity;
- Sun: Corona;
- Sun: Flares;
- X-Rays;
- Astrophysics
- E-Print:
- 7 pages, 3 figures, accepted by ApJ Letters