HR: 1340h
AN: SM43A-1217    [Abstracts]
TI: Waiting-time distributions of solar eruptions and the evidence for sympathetic flares
AU: MOON, Y
EM: yjmoon@kasi.re.kr
AF: Korea Astronomy and Space Science Institute, 61-1 Whaamdong, Yooseong, Daejeon, 305-348 Korea, Republic of
AU: * Choe, G
SM43A-1217 AF: Princeton Plasma Physics Lab., Princeton Univerity, Princeton, NJ 08543-0451 United States
AU: PARK, Y
SM43A-1217 AF: Korea Astronomy and Space Science Institute, 61-1 Whaamdong, Yooseong, Daejeon, 305-348 Korea, Republic of
AU: KIM, Y
SM43A-1217 AF: Korea Astronomy and Space Science Institute, 61-1 Whaamdong, Yooseong, Daejeon, 305-348 Korea, Republic of
AB: In this study we have examined the waiting-time distributions of solar flares and CMEs as well as the evidence for sympathetic events. First, we considered GOES X-ray flares stronger than C1 class during the solar maximum between 1989 and 1991 and all LASCO CMEs from 1999 to 2001. The observed waiting-time distributions are found to be well represented by nonstationary Poisson probability function with time-varying mean occurrence rates, implying that independent events outnumber sympathetic ones. It is also found that there are no systematic relationships between peak fluxes of flares and their waiting-time distributions. The above findings support an idea that the solar corona is in a self-organized critical state. Second, we collected 48 pairs of near simultaneous flares whose positional information and Yohkoh soft X-ray telescope images are available. To select the active regions that probably have sympathetic flares, we have estimated the ratio R of actual flaring overlap time to random-coincidence overlap time for 38 active region pairs. We have then compared the waiting-time distributions for the two different groups of active region pairs (R > 1 and R < 1) with corresponding nonstationary Poisson distributions. As a result, we find a remarkable overabundance of short waiting times for the group with R > 1. This is the first time such strong statistical evidence has been found for the existence of sympathetic flares.
DE: 3265 Stochastic processes (3235, 4468, 4475, 7857)
DE: 7513 Coronal mass ejections (2101)
DE: 7519 Flares
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005