e-VLBI observations of Circinus X-1: monitoring of the quiescent and flaring radio emission on au scales
e-VLBI observations of Circinus X-1: monitoring of the quiescent and flaring radio emission on au scales
复制标题
Circinus X-1 的 e-VLBI 观测：监测 au 尺度上的静态和耀斑无线电发射
DOI：
10.1111/j.1365-2966.2011.18660.x
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发表时间：
2011
影响因子：
4.8
通讯作者：
U. Southampton
中科院分区：
文献类型：
--
作者：
A. Moin;C. Reynolds;J. Miller;S. Tingay;C. Phillips;A. Tzioumis;G. Nicolson;R. P. F. ICRARCurtin;Atnfcass;HartRAO;U. Southampton
最近用电子甚长基线干涉测量法 (e-VLBI) 对奇特的中子星 X 射线双星圆规座 X-1 进行了探测，这表明紧凑、不变的射电发射在双星系统的整个 16.6 d 轨道上持续存在。我们展示了使用澳大利亚长基线阵列在实时 e-VLBI 模式下进行的高角分辨率监测活动的结果。对圆规座 X-1 的 e-VLBI 观测是在 20 天的时间内隔天进行的，覆盖了整个双星轨道。在经过近星体后的轨道相位上清楚地检测到了与圆规座 X-1 相关的紧凑型射电源，但在任何其他轨道相位上均未检测到紧凑型射电发射源，从而排除了在我们的敏感度水平上存在持续的紧凑型发射区域的可能性。在我们的 1.4 GHz 监测活动的任何时期都没有解决该喷流问题，这表明之前推断该源中存在的超相对论流很可能是暗流。我们在之前对 Circinus X-1 的无线电监测中讨论了这些发现。
A recent detection of the peculiar neutron star X-ray binary Circinus X-1 with electronic very long baseline interferometry (e-VLBI) prompted the suggestion that compact, non-variable radio emission persists through the entire 16.6-d orbit of the binary system. We present the results of a high angular resolution monitoring campaign conducted with the Australian Long Baseline Array in real-time e-VLBI mode. e-VLBI observations of Circinus X-1 were made on alternate days over a period of 20 d covering the full binary orbit. A compact radio source associated with Circinus X-1 was clearly detected at orbital phases following periastron passage, but no compact radio emission was detected at any other orbital phase, ruling out the presence of a persistent, compact emitting region at our sensitivity levels. The jet was not resolved at any epoch of our 1.4-GHz monitoring campaign, suggesting that the ultrarelativistic flow previously inferred to exist in this source is likely to be dark. We discuss these findings within the context of previous radio monitoring of Circinus X-1.