A Pulsing X-Ray Source in Circinus

Abstract

A pulsing X-ray source with period 685 + 30 ms has been observed in Circinus. Approximately 10 percent of the 1-t0-keV X-ray emission of the source is contained in these pulses. A spectrum of the source is presented and may be fitted by a thermal bremsstrahlung emission mechanism with T = 3.5 X I0 K, or by a blackbody at T = 1.1 X t0 K, both subject to heavy absorption.