论文标题
M Supergiant高质量X射线二进制4U 1954+31
The M Supergiant High Mass X-Ray Binary 4U 1954+31
论文作者
论文摘要
X射线二进制4U 1954+31已被归类为含有M巨人和中子星（NS）的低质量X射线二进制（LMXB）。它也被包括在罕见的X射线共生二进制室（SYXB）中。 M Star的Gaia视差，红外颜色，光谱，丰度和轨道特性表明，该系统中的酷星不是低质量巨人，而是高质量M超级巨人。因此，4U 1954+31是一个高质量X射线二进制（HMXB），其中包含晚期超级巨人。这是这种类型的唯一已知的二进制系统。 m i的质量是9 $^{+6} _ { - 2} $ m $ _ \ odot $，将该系统的年龄在12-50 Myr的范围内，NS不超过43 Myr。 NS的自旋期是最长的5小时之一。 M I Plus NS二进制系统的存在与恒星进化论一致，该系统是HMXB种群中进化的成员。
The X-ray binary 4U 1954+31 has been classified as a Low Mass X-ray Binary (LMXB) containing a M giant and a neutron star (NS). It has also been included in the rare class of X-ray symbiotic binaries (SyXB). The Gaia parallax, infrared colors, spectral type, abundances, and orbital properties of the M star demonstrate that the cool star in this system is not a low mass giant but a high mass M supergiant. Thus, 4U 1954+31 is a High Mass X-ray Binary (HMXB) containing a late-type supergiant. It is the only known binary system of this type. The mass of the M I is 9$^{+6}_{-2}$ M$_\odot$ giving an age of this system in the range 12 - 50 Myr with the NS no more than 43 Myr old. The spin period of the NS is one of the longest known, 5 hours. The existence of M I plus NS binary systems is in accord with stellar evolution theory, with this system a more evolved member of the HMXB population.
