Near-Infrared Spectra of the Black Hole X-Ray Binary A0620-00
Near-Infrared Spectra of the Black Hole X-Ray Binary A0620-00
复制标题
黑洞 X 射线双星 A0620-00 的近红外光谱
DOI：
10.1086/518820
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
M. Bitner
中科院分区：
文献类型：
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作者：
C. Froning;E. L. Robinson;M. Bitner
我们提供了A0620-00在IRTF上用SpeX获得的宽带近红外（NIR）光谱。光谱的特点是由一个蓝色的连续谱上叠加了广泛的发射线的H I和He II和主机的较窄的吸收线的中性金属和分子。光谱类型标准星星光谱定标到A0620-00的去红光谱K超过A0620 -00的光谱J和H的所有恒星的光谱类型K7 V或更早，表明施主星星，除非晚于K7 V，不能在A0620-00的唯一的近红外通量源。此外，即使在100%施主星星贡献下，K3 V光谱中的原子吸收线相对于A0620-00的原子吸收线也太弱，将A0620-00的施主星星的光谱类型限制在K 3 V之后。将A0620-00的光谱与标度K星星的光谱进行比较，表明A0620-00的CO吸收特征明显较弱。00比在场矮星。Roche叶填充施主星星的定标模型光谱与A0620-00光谱的拟合表明，当C丰度降低到[C/H] =-1.5时，CO吸收线得到最佳匹配。H波段施主星星的贡献为（82 ± 2）%。结合Froning &罗宾逊和Marsh等人先前发表的结果，这给出了A0620-00中黑洞的精确质量M1 = 9.7 ± 0.6 M。
We present broadband near-IR (NIR) spectra of A0620-00 obtained with SpeX on the IRTF. The spectrum is characterized by a blue continuum on which are superimposed broad emission lines of H I and He II and a host of narrower absorption lines of neutral metals and molecules. Spectral type standard star spectra scaled to the dereddened spectrum of A0620-00 in K exceed the A0620-00 spectrum in J and H for all stars of spectral type K7 V or earlier, demonstrating that the donor star, unless later than K7 V, cannot be the sole NIR flux source in A0620-00. In addition, the atomic absorption lines in the K3 V spectrum are too weak with respect to those of A0620-00 even at 100% donor star contribution, restricting the spectral type of the donor star in A0620-00 to later than K3 V. Comparison of the A0620-00 spectrum to scaled K star spectra indicates that the CO absorption features are significantly weaker in A0620-00 than in field dwarf stars. Fits of scaled model spectra of a Roche lobe-filling donor star to the spectrum of A0620-00 show that the best match to the CO absorption lines is obtained when the C abundance is reduced to [C/H] = -1.5. The donor star contribution in the H wave band is determined to be (82 ± 2)%. Combined with previous published results from Froning & Robinson and Marsh et al., this gives a precise mass for the black hole in A0620-00 of M1 = 9.7 ± 0.6 M☉.