Flaring Time Interval Distribution and Spatial Correlation of Major Xray Flares 

YongJae Moon Submitted: 20020405 17:52
A statistical study is performed on Xray flares stronger than C1 class that erupted
during the solar maximum between 1989 and 1991. We have investigated the flaring
time interval distribution (waitingtime distribution) and the spatial correlation of
successive flare pairs. The observed waitingtime distribution for the whole data is
found to be well represented by a nonstationary Poisson probability function with time
varying mean flaring rates.
The period most suitable for a constant mean flaring rate is determined
to be 23 days by a KolmogorovSmirnov test.
We have also found that the waitingtime distribution for flares in
individual active regions follows a stationary Poisson probability function
mexp(mt) with a corresponding mean flaring
rate.
Therefore, the flaring probability within a given time is given by 1exp(mt), when
the mean flaring rate m is properly estimated.
It is also found that there is no systematic relationships between peak fluxes of
flares and their waitingtime distributions.
The above findings support the idea that the
solar corona is in a selforganized critical state.
A comparison of the angular distances of successively observed flare pairs with those of
hypothetical flare pairs generated by random distribution shows a positive angular
correlation within about 10 degrees (sim 180 arcsec in the observing field)
of angular separation, which suggests
that homologous flares occurring in the same active region should outnumber
sympathetic flares.
Authors: Y.J. Moon, G. S. Choe, H. S. Yun, Y. D. Park
Projects:

Publication Status: JGRspace physics, 2001, 106(A12), 2995129961
Last Modified: 20020405 17:52


