概括
1988年,四颗核卫星探测到高能马射线. 这些短暂的卫星信号提供了关于玛射线天文学背景的新数据.
科学领域:
- *天体物理学和空间科学 *天体物理学和空间科学
- * 高能物理 高能物理
背景情况:
- *从太空探测到的马射线对于理解天体现象至关重要.
- *以前的研究主要集中在确定天体马射线源,对短暂的人工源的数据有限.
研究的目的:
- * 报告核动力卫星探测到短暂的马射线信号.
- *分析这些信号的特性,包括持续时间,亮度和能量频谱.
- * 评估这些人工光源对整体马射线背景的贡献.
主要方法:
- *使用气球载双康普顿马射线望远镜在澳大利亚爱丽丝泉上空35公里的高度.
- * 在1988年4月15日收集了30小时的观测数据.
- *分析了来自四颗核动力卫星的短暂信号 (确定了Cosmos 1900和Cosmos 1932).
主要成果:
- *检测到四个短暂的马射线信号,能量在0.3到8兆电子伏特 (MeV) 之间.
- *确定信号持续时间从21秒到113秒,对应于260-800公里的轨道高度.
- *计算的亮度在每秒 (3.9 ± 1.0) x 10^15 和 (1.30 ± 0.32) x 10^16 光子之间.
- * 能量频谱配备了一个指数,其指数为2.4 ± 1.4.
结论:
- * 检测到的短暂马射线事件起源于核动力卫星.
- *这些人造源导致了马射线天文学观测中的背景噪声.
- *这些发现强调了区分天体和人工马射线源的重要性.
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