论文标题
Swift J0503.7-2819：短期异步极性或溪流喂养的中间极性
Swift J0503.7-2819: A Short-Period Asynchronous Polar or Stream-Fed Intermediate Polar
论文作者
论文摘要
我们分析了灾难性变量Swift J0503.7-2819的7.4 hr XMM-Newton光曲线，该曲线先前使用光学周期作为中间极（IP）进行分类，轨道周期为0.0567天。 X射线中不存在于975 s的975 s的光度信号，并且很容易理解为准周期性振荡。相反，X射线光曲线显示出高度异步极（AP）或流馈出IP的清晰行为。可以通过两种情况中的任何一个描述：一种可以在一个圆和两极吸积之间切换，另一个在两个杆之间完全交替交替。这两个模型中的自旋周期分别为0.0455天和0.0505天。因此，自旋频率$ω$比轨道频率$ω$快24％或12％，并且旋转和轨道之间的相应节拍周期为0.231天或0.462天。在光曲线中看到的简短吸收事件的间隔是有利于更长的旋转和跳动时期的方式。使用来自过渡系外行星调查卫星（TESS）和小行星地面影响的最后一个警报系统（ATLAS）的数据确认并完善了这些时期。 Swift J0503.7-2819的短节奏周期使其非常适合解决这一常见困境，这相当于确定功率谱中的主要信号是$ω$还是$2Ω-ω$。
We analyze a 7.4 hr XMM-Newton light curve of the cataclysmic variable Swift J0503.7-2819, previously classified using optical periods as an intermediate polar (IP) with an orbital period of 0.0567 days. A photometric signal at 975 s, previously suggested to be the spin period, is not present in X-rays and is readily understood as a quasi-periodic oscillation. The X-ray light curve instead shows clear behavior of a highly asynchronous polar (AP) or stream-fed IP. It can be described by either of two scenarios: one which switches between one-pole and two-pole accretion, and another in which accretion alternates fully between two poles. The spin periods in these two models are 0.0455 days and 0.0505 days, respectively. The spin frequency $ω$ is thus either 24% faster or 12% faster than the orbital frequency $Ω$, and the corresponding beat period between spin and orbit is 0.231 days or 0.462 days. Brief absorption events seen in light curve are spaced in a way that may favor the longer spin and beat periods. These periods are confirmed and refined using data from the Transiting Exoplanet Survey Satellite (TESS) and the Asteroid Terrestrial-impact Last Alert System (ATLAS). The short beat cycle of Swift J0503.7-2819 makes it well-suited to resolving this common dilemma, which amounts to deciding whether the main signal in the power spectrum is $ω$ or $2ω-Ω$.
