We report follow-up observations of five cataclysmic variable candidates from LAMOST published by Hou et al. (2020). LAMOST J024048.51+195226.9 is the most unusual of the five; an early-M type secondary star contributes strongly to its spectrum, and its spectral and photometric behavior are strikingly reminiscent of the hitherto-unique propeller system AE Aqr. We confirm that a 7.34-hr period discovered in the Catalina survey data (Drake et al. 2014) is orbital. Another object, LAMOST J204305.95+341340.6 appears to be a near twin of the novalike variable V795 Her, with an orbital period in the so-called 2-3 hour "gap". LAMOST J035913.61+405035.0 is evidently an eclipsing, weakly-outbursting dwarf nova with a 5.48-hr period. Our spectrum of LAMOST J090150.09+375444.3 is dominated by a late-type secondary and shows weak, narrow Balmer emission moving in phase with the absorption lines, but at lower amplitude; we do not see the HeII 4686 emission evident in the published discovery spectrum. We again confirm that a period from the Catalina data, in this case 6.80 hr, is orbital. LAMOST J033940.98+414805.7 yields a radial-velocity period of 3.54 hr, and its spectrum appears to be typical of novalike variables in this period range. The spectroscopically-selected sample from LAMOST evidently includes some interesting cataclysmic variables that have been unrecognized until now, apparently because of the relatively modest range of their photometric variations.

中文翻译：

---

LAMOST 发现的五个灾难性候选变量的后续研究

我们报告了侯等人发表的来自 LAMOST 的五个灾难性变量候选者的后续观察。(2020)。LAMOST J024048.51+195226.9 是五个中最不寻常的；一颗早期 M 型次级星对其光谱有很大贡献，它的光谱和光度学行为惊人地让人联想到迄今为止独特的螺旋桨系统 AE Aqr。我们确认在 Catalina 调查数据（Drake 等人，2014 年）中发现的 7.34 小时周期是轨道周期。另一个天体 LAMOST J204305.95+341340.6 似乎是类新星变星 V795 Her 的近双胞胎，轨道周期在所谓的 2-3 小时“间隙”中。LAMOST J035913.61+405035.0 显然是一颗食相、弱爆发的矮新星，周期为 5.48 小时。我们的 LAMOST J090150.09+375444.3 谱以晚型次生为主，显示弱，窄巴尔默发射与吸收线同相移动，但幅度较低；我们在公布的发现光谱中没有看到明显的 HeII 4686 发射。我们再次确认来自 Catalina 数据的周期，在本例中为 6.80 小时，是轨道周期。LAMOST J033940.98+414805.7 产生了一个 3.54 小时的径向速度周期，它的光谱在这个周期范围内似乎是典型的类新星变量。来自 LAMOST 的光谱选择样本显然包括一些有趣的灾难性变量，这些变量直到现在仍未被识别，显然是因为它们的光度变化范围相对适中。在这种情况下 6.80 小时，是轨道。LAMOST J033940.98+414805.7 产生了一个 3.54 小时的径向速度周期，它的光谱在这个周期范围内似乎是典型的类新星变量。来自 LAMOST 的光谱选择样本显然包括一些有趣的灾难性变量，这些变量直到现在仍未被识别，显然是因为它们的光度变化范围相对适中。在这种情况下 6.80 小时，是轨道。LAMOST J033940.98+414805.7 产生了一个 3.54 小时的径向速度周期，它的光谱在这个周期范围内似乎是典型的类新星变量。来自 LAMOST 的光谱选择样本显然包括一些有趣的灾难性变量，这些变量直到现在仍未被识别，显然是因为它们的光度变化范围相对适中。