The Ultraviolet Imaging Telescope (UVIT) on board the AstroSat observatory has imaged the Andromeda galaxy (M31) from 2017 to 2019 in the far- and near-UV (FUV and NUV) with the high spatial resolution of ≃1″. The survey covered the large sky area of M31 with a set of observations (Fields), each 28′ in diameter. Field 1 was observed in two epochs with the F148W filter, separated by ≃1133 days (≃3.10 yr). The 6.4 kpc diameter Field 1 (at the distance of M31) includes a substantial part of the inner spiral arms of the galaxy. We identify UVIT sources in both epochs of Field 1 and obtain catalogs of sources that are variable in FUV at >3σ and >5σ confidence level. The fraction of FUV-variable sources is higher for brighter sources, and the fraction is higher in the two main spiral arms compared to other areas. This is evidence that a significant fraction of the FUV variables are associated with hot young stars. Source counterparts are found for 42 of the 86 >5σ FUV variables using existing catalogs. The counterparts include 10 star clusters, 6 H II regions, 5 regular or semiregular variables, 6 other variables, and 6 nova or nova candidates. The UVIT FUV–NUV and FUV–FUV color–magnitude diagrams confirm the association of most of the FUV variables with hot young stars. A catalog of UVIT photometry for the variable sources is presented.

AstroSat 天文台上的紫外成像望远镜 (UVIT) 已对 2017 年至 2019 年的仙女座星系 (M31) 进行了远紫外和近紫外 (FUV 和 NUV) 成像，具有≃1" 的高空间分辨率。该调查覆盖了 M31 的大片天空区域，其中包含一组观测值（场），每个观测值的直径为 28 英尺。使用 F148W 滤波器在两个时期内观察到场 1，相隔 ≃1133 天（≃3.10 年）。直径为 6.4 kpc 的场 1（在 M31 的距离处）包括星系内部旋臂的大部分。我们在场 1 的两个时期中识别 UVIT 源，并获得 FUV 中在 >3 σ和 >5 σ处可变的源目录置信水平。对于较亮的源，FUV 可变源的比例更高，与其他区域相比，两个主要旋臂中的比例更高。这证明很大一部分 FUV 变量与炽热的年轻恒星有关。使用现有目录为 86 个 >5 σ FUV 变量中的42 个找到源对应物。对应的星团包括 10 个星团、6 个 H II 区、5 个规则或半规则变星、6 个其他变星和 6 个新星或新星候选者。UVIT FUV-NUV 和 FUV-FUV 色阶图证实了大多数 FUV 变量与热年轻恒星的关联。提供了可变光源的 UVIT 光度测量目录。