标题： ZTF中识别出的具有爆发/掩食状变化的类星体 显示英文标题

标题： Quasars with Flare/Eclipse-like Variability Identified in ZTF

摘要： 活动星系核（AGNs）以光学/紫外波段的光变而闻名，其中大多数可以通过阻尼随机行走模型很好地描述。与吸积盘无关的物理过程，例如潮汐瓦解事件（TDE）或移动前景尘埃云，可以在光学光变曲线上引起类似耀发和掩食的特征。需要长期监测和高采样率观测来识别这些特征。 通过结合斯隆数字巡天（SDSS）、全景巡天望远镜及快速响应系统（Pan-STARRS）以及兹维基暂现巡天设施（ZTF）的巡天数据，我们从SDSS类星体目录（约83,000个）中识别出一个罕见样本（11个）。这些类星体在亮度上基本保持恒定，但在ZTF DR2时期表现出快速的光学变化。 为了研究这些耀发/掩食似变化的可能起源，我们提议使用加那利大型望远镜（GTC）进行第二期光谱观测。我们发现吸积率的变化在这些类星体的变化中起着重要作用。在这之中，我们确定了两个“变脸”活动星系核（CL-AGN）候选体：SDSS J1427+2930 和 SDSS J1420+3757。前者亮度变化可能是由于超大质量黑洞吸积增强或潮汐瓦解事件引起，而后者则更可能与吸积率的变化有关。 显示英文摘要

摘要： Active galactic nuclei (AGNs) are known to exhibit optical/UV variability and most of them can be well modeled by the damped random walks. Physical processes that are not related to the accretion disk, such as tidal disruption events (TDE) or moving foreground dusty clouds, can cause flare-like and eclipse-like features in the optical light curve. Both long-term and high-cadence monitoring are needed to identify such features. By combining the Sloan Digital Sky Survey (SDSS), Panoramic Survey Telescope, and Rapid Response System (Pan-STARRS) with the Zwicky Transient Facility (ZTF) survey, we are able to identify a rare sample (11) out of the SDSS quasar catalog (around 83, 000). These quasars exhibit more or less constant brightness but show rapid optical variation in the ZTF DR2 epochs. To investigate the possible origins of these flare/eclipse-like variabilities, we propose the second epoch spectroscopic observations with the Gran Telescopio CANARIAS (GTC). We find that the change in accretion rate plays a significant role in these quasar variabilities. Among them, we identify two Changing-Look Active Galactic Nuclei (CL-AGN) candidates: SDSS J1427+2930 and SDSS J1420+3757. The luminosity change of the former may be caused by the enhanced SMBH accretion or the tidal disruption event, while the latter is more related to the change in the accretion rate.