类星体:通过非常长的基线干涉测量揭示了几百万秒的弧度结构
概括
无线电干扰仪的观测显示了类星体3C 279和3C 273的微型结构. 数据表明,3C 279有两个距离大约20光年的无线电发射点,这可能允许检测相对论运动.
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- 无线电天文学 无线电天文学
背景情况:
- 类星体是活跃的银河系核,在电磁谱中发射强大的辐射.
- 了解类星体无线电辐射的细微结构对于探测它们的物理过程和环境至关重要.
研究的目的:
- 为了研究类星体3C 279和3C 273的无线电辐射中的细结构.
- 用物理模型来解释观察到的无线电发射模式.
主要方法:
- 使用Goldstone-Haystack无线电干扰仪进行高分辨率观测.
- 分析边缘振幅数据以推断无线电发射源的空间分布.
主要成果:
- 在3C 279和3C 273的无线电辐射中检测细结构.
- 对于3C 279,数据与两个相等贡献的排放点相一致,它们相隔约1.55 x 10^-3弧秒 (约20光年).
- 对3C 279的分离测量具有形式不确定性,允许在一年内潜在检测相对论自动运动.
结论:
- 观察到的类星体无线电辐射中的微型结构为我们提供了关于它们紧的源区域的见解.
- 对于3C 279的结果表明了复杂的发射结构,可能表明相对论喷气或二进制活跃银河系核.
- 需要进一步的观测来证实对两个类星体的解释,特别是3C 273.
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