AI 中文总结
该研究利用TESS对超14000颗恒星七年短周期观测，搜索耀斑活动长期变化，经测试给出相关极限与结果，识别出17颗有耀斑率长期变化迹象的恒星，为恒星磁变何时首次出现提供关键限制。
AI 中文摘要
磁活动周期对恒星发电机提供了基本限制，但在太阳之外仍难以识别。不过，近期研究表明耀斑是活动周期行为的独特示踪剂。本研究使用凌日系外行星勘测卫星（TESS）对连续视场带中超过14000颗恒星的七年短周期观测，搜索耀斑活动的长期变化。对每颗恒星进行注入和恢复测试，给出耀斑检测阈值和发现结果的特征完备性极限。从中识别出17颗耀斑率有长期变化迹象的恒星，它们涵盖不同有效温度、自转周期和耀斑变化形态。一颗G型恒星TIC 167344043是最清晰的类太阳案例。结果识别出比文献中典型恒星活动周期目标自转更快且有耀斑活动的恒星中的候选活动周期，为类周期磁变何时首次出现提供关键限制。
英文摘要
Magnetic activity cycles provide a fundamental constraint on stellar dynamos, but remain difficult to identify beyond the Sun. However, recent studies have shown that flares offer a unique tracer of activity cycle behavior. In this study, we use seven years of short-cadence observations from the Transiting Exoplanet Survey Satellite (TESS) for over 14,000 stars in the Continuous Viewing Zone to search for long-term changes in flare activity. For each star, we perform injection and recovery tests and provide well-characterized completeness limits for flare detection thresholds, and flare finding results. From this search, we identify 17 stars with evidence of long-term variability in flare rate, synonymous with activity cycle behavior. These candidates span a range of effective temperatures, rotation periods, and flare-variability morphologies. One G-type star, TIC 167344043, stands out as the clearest solar-like case, despite rapid rotation and superflare activity. Our results identify candidate activity cycles in stars that are more rapidly rotating and flare-active than the typical stellar-activity-cycle targets in the literature. These systems probe a new regime where stellar dynamos are still evolving, providing critical constraints on when cycle-like magnetic variability first emerges.
Comments21 pages, 9 figures with more available online, 3 tables. Submitted to AAS journals
