天鹅座X-1硬X射线的能量谱

THE ENERGY SPECTRUM OF Cyg X-1

1985年9月22日,我们用空间硬X射线望远镜HAPI-2,在我国的高空气球上,对天鹅座X-1进行了观测,望远镜几何面积为140cm^2,观测能区20—200keV,空间定向精度±0.2°。获得的硬X射线能谱陡,总辐射能流LX～1.0×1^(37)erg/sec,低于常规态。本文将介绍望远镜的性能和观测过程,能谱分析的结果,并对当时天鹅座X-1可能的“态”进行讨论。

We present here an observational result for the hard X-ray spectrum of Cyg X-1 in 20-200 keV range, which was obtained by a balloon-borne CsI-NaI phoswich type telescope launched at Xianhe Balloon Facilities on Sep. 22, 1985. The X-ray luminosity in 10-200 keV is estimated as (1.07 ± 0.08) × 1037 ergs/s. It indicates that Cyg X-1 may not be in the normal low state at that time.