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Updated: Jul 11, 2026

10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
概括
1990年出现了一种新的银河系中心瞬态 (GCT) 无线电源,在一个月后达到强度峰值. 这种短暂可能是来自X射线二进制系统的同步子发射的结果.
科学领域:
- 无线电天文学 无线电天文学
- 银河中心研究研究银河系中心研究.
- 暂时的天文现象是暂时的天文现象.
背景情况:
- 一个新的无线电源,银河系中心瞬态 (GCT),在1990年底在我们银河系的中心附近出现.
- 银河系的强度与射手座A* (Sgr A*) 的强度相美,这是银河系核心的已建立的紧无线电源.
研究的目的:
- 分析新发现的银河系中心瞬态 (GCT) 的特征和起源.
- 用无线电吸收和红外观测来确定GCT的位置和性质.
主要方法:
- 随着时间的推移,监测GCT的流量密度和无线电频谱.
- 使用中性 (HI) 和 (OH) 吸收线谱学.
- 将GCT吸收特征与已知的银河系中心来源进行比较.
- 分析该地区的红外图像.
主要成果:
- 在GCT中,流量密度迅速增加,在一个月内达到峰值,随后在三个月内逐渐下降.
- 在GCT的上升和衰退阶段,始终观察到一个的无线电频谱.
- HI吸收表明GCT与银河系中心的距离很近,类似于Sgr A*.
- HI和OH的观测显示了与+20公里/秒的分子云相一致的吸收,这表明GCT嵌入或位于这个云后面.
- 红外观测证实了这种分子云的存在,但其不透明度不足以掩盖附近的超新星.
结论:
- GCT位于靠近或在分子云中,相对于当地的静止标准,其移动速度为+20公里/秒.
- 观测到的GCT属性与超新星不一致.
- 对GCT最可能的解释是来自X射线二进制系统内的同步子辐射的短暂无线电发射.
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