标题： RX J2133.7+5107：新长周期交错极的识别 显示英文标题

标题： RX J2133.7+5107 : Identification of a new long period Intermediate Polar

摘要： 我们首次报道了对ROSAT巡天中识别出的X射线源RX J2133.7+5107的时间分辨光度和光谱光学观测。通过快速测光发现了明显的持续光学光脉动，周期为P_{欧米茄} = (570.823 ± 0.013) s，我们认为这是吸积白矮星的自旋周期。强发射线的径向速度曲线显示出一个周期为P_{Ω} = (7.193 ± 0.016) 小时的调制，被确认为轨道周期。这些观测结果表明该源属于磁性激变变星中的中间极子类（IPs）。由于仅有4个轨道周期更长的IPs，RX J2133.7+5107是其中较宽的系统之一。它是一个独特的IP，其轨道周期位于所谓的(6-10)小时IP空档的中间，并且显示出显著的非同步性，比值P_{欧米茄}/P_{Ω}为0.02。将其归因于白矮星的运动时，发射线的轨道调制产生了质量函数f_m = (1.05 ± 0.21) × 10^{-2} Msun，对于可能的倾角i < 45度和白矮星质量M_{wd} = (0.6-1.0) Msun，对应于次级质量M_{s} > (0.27-0.37) Msun。 显示英文摘要

摘要： We report the first time-resolved photometric and spectroscopic optical observations of the X-ray source RX J2133.7+5107, identified in the ROSAT survey. A clear persistent optical light pulsation is discovered with fast photometry at a period of P_{omega} =(570.823 +/-0.013) s which we associate with the spin period of an accreting white dwarf. Radial velocity curves of the strong emission lines show modulation with a period of P_{Omega} =(7.193 +/- 0.016) hr, identified as the orbital period. These observations establish that the source is a member of the intermediate polar class (IPs) of magnetic cataclysmic variables. With only 4 IPs with longer orbital periods, RX J2133.7+5107 is among the widest systems. It is a unique IP with an orbital period in the middle of the so-called (6-10)hr IP gap and it shows a significant degree of asynchronism with a ratio P_{omega}/P_{Omega} of 0.02. When attributed to the motion of the white dwarf, the emission lines orbital modulation yields a mass function of f_m = (1.05 +/- 0.21) 10^{-2} Msun which, for a probable inclination i < 45 deg and a white dwarf mass M_{wd} = (0.6-1.0) Msun, corresponds to a secondary mass M_{s} > (0.27-0.37) Msun.