CHANDRA RESOLVES THE T TAURI BINARY SYSTEM RW AUR
CHANDRA RESOLVES THE T TAURI BINARY SYSTEM RW AUR
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Chandra 解析 T TAURI 双星系统 RW AUR
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
M. Guedel
中科院分区：
文献类型：
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作者：
S. Skinner;M. Guedel
RW Aur是一个多T金牛座系统，由一个早K型主星（A）和一个K5伴星（B）组成，距离为1.“4。RW Aur A驱动双极光学射流，其光学特性良好。我们目前的结果敏感的钱德拉观测，其主要目标是寻找证据的软扩展X射线发射沿着喷流，已经看到了其他几个附近的金牛T星。钱德拉望远镜清楚地分辨出这对双星，并发现这两颗恒星都是X射线源。这两颗恒星的X射线光谱揭示了冷等离子体和热等离子体的证据。令人惊讶的是，质量较小的次级恒星的X射线光度至少是初级恒星的两倍，并且是可变的。这种差异是由于其X射线光度是在低端的经典金牛座T星类似的质量的基础上建立的相关性的范围内的主要。去卷积软带图像显示的证据轻微向外伸长的源结构的RW Aur A沿着蓝移射流轴内的中央弧秒。此外，在红移轴上距离星星1.“2 ± 0.”2的偏移处，存在一个微弱的X射线发射峰。从以前的光学研究中确定的非投影射流速度太低，无法将这种微弱的发射峰解释为激波加热的射流等离子体。因此，除非在红移喷流的流速被低估，其他机制，如磁喷流加热可能涉及。
RW Aur is a multiple T Tauri system consisting of an early-K type primary (A) and a K5 companion (B) at a separation of 1.″4. RW Aur A drives a bipolar optical jet that is well characterized optically. We present results of a sensitive Chandra observation whose primary objective was to search for evidence of soft extended X-ray emission along the jet, as has been seen for a few other nearby T Tauri stars. The binary is clearly resolved by Chandra and both stars are detected as X-ray sources. The X-ray spectra of both stars reveal evidence for cool and hot plasma. Surprisingly, the X-ray luminosity of the less-massive secondary is at least twice that of the primary and is variable. The disparity is attributed to the primary whose X-ray luminosity is at the low end of the range for classical T Tauri stars of similar mass based on established correlations. Deconvolved soft-band images show evidence for slight outward elongation of the source structure of RW Aur A along the blueshifted jet axis inside the central arcsecond. In addition, a faint X-ray emission peak is present on the redshifted axis at an offset of 1.″2 ± 0.″2 from the star. Deprojected jet speeds determined from previous optical studies are too low to explain this faint emission peak as shock-heated jet plasma. Thus, unless flow speeds in the redshifted jet have been underestimated, other mechanisms such as magnetic jet heating may be involved.