Flare-time temperature in soft x-ray sources

Temperatures in flare-time soft X-ray sources have been obtained for selected events by using measurements in 0.5-3 A and 1-s A bands from OGO-4/SR-9 satellites. Higher temperature is assumed for emission below 3 A, and two temperatures (T1 and T2) for 0.5-3 A and 3-8 A spectral ranges. It is shown that source temperature falls rapidly in the initial phase of decay with an exponential cooling time constant of about 52 s. Subsequently the rate of fall of temperature becomes slow. The initial rapid fall can be attributed to the presence of a non thermal component.