schriste@ssl

September 6, 2008

Fall AGU 2008 Meeting

Filed under: Microflares, Presentations, Work — Steven Christe @ 0:09 am

RHESSI Workshop Abstract

The Microflare Height Distribution
Christe, Steven; Krucker, Sam

We present an in-depth statistical survey of flare heights of all X-ray microflares as observed by RHESSI between March 2002 and March 2007, a total of >25,000 events, an order of magnitude larger then previous studies. The microflares were found using a new flare-finding algorithm designed to search the 6–12 keV count-rate when RHESSI’s full sensitivity was available in order to find the smallest events. The flare centroid position are found at the peak time and as a function of energy (3-6, 6-12, 12-25 keV). Flares are found to occur only in active regions, not in the “quiet” Sun. Flare heights are found using two independent methods including that of Matsushita (1992). The distribution of flares at the limb are fitted with a Monte Carlo simulations and the flare height deduced. We find that the 6-12 keV flare heights are consistent with a flare height of ~3 arcseconds above the photosphere with small separation between the thermal and nonthermal sources. The Matsushita method confirm these values….

Powered by WordPress