In this paper, we present photometry for young star clusters in M31, which are selected from Caldwell et al. These star clusters have been observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March. The BATC images including these star clusters are taken with 15 intermediate-band filters covering 3000-10000 ?. Combined with photometry in the GALEX far- and near-ultraviolet, broadband UBV RI, SDSS ugriz, and infrared JHK s of Two Micron All Sky Survey, we obtain their accurate spectral energy distributions (SEDs) from 1538 to 20000 ?. We derive these star clusters' ages and masses by comparing their SEDs with stellar population synthesis models. Our results are in good agreement with previous determinations. The mean value of age and mass of young clusters (2 Gyr) is about 385?Myr and 2 × 104 M ☉, respectively. There are two distinct peaks in the age distribution, a highest peak at age ~60?Myr and a secondary peak around 250?Myr, while the mass distribution shows a single peak around 104 M ☉. A few young star clusters have two-body relaxation times greater than their ages, indicating that those clusters have not been well dynamically relaxed and therefore have not established the thermal equilibrium. There are several regions showing aggregations of young star clusters around the 10?kpc ring and the outer ring, indicating that the distribution of the young star clusters is well correlated with M31's star-forming regions. The young massive star clusters (age ≤100?Myr and mass ≥104 M ☉) show apparent concentration around the ring splitting region, suggesting a recent passage of a satellite galaxy (M32) through M31 disk.
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机译：在本文中，我们介绍了从Caldwell等人选出的M31中年轻星团的光度法。 1995年2月至2008年3月，在北京-亚利桑那-台湾-康涅狄格州（BATC）多色天空调查中已观察到这些星团。包括这些星团的BATC图像是用15个覆盖3000-10000？的中频带滤波器拍摄的。结合GALEX远紫外和近紫外光，宽带UBV RI，SDSS ugriz和“两微米全天候”测量的红外JHK的光度法，我们获得了1538至20000？的准确光谱能量分布（SED）。通过将它们的SED与恒星群体合成模型进行比较，我们得出了这些星团的年龄和质量。我们的结果与以前的结论非常吻合。年轻星团（<2 Gyr）的年龄和质量的平均值分别约为385？Myr和2×104 M☉。年龄分布中有两个明显的峰，一个最高峰出现在约60？Myr，第二个峰在250？Myr附近，而质量分布显示一个峰在104 M around附近。一些年轻的星团的两体弛豫时间大于其年龄，这表明这些星团没有得到很好的动态弛豫，因此尚未建立热平衡。有几个区域显示出10？kpc环和外环周围的年轻恒星团的聚集，这表明年轻恒星团的分布与M31的恒星形成区域有很好的相关性。年轻的大质量恒星团（年龄≤100？Myr，质量≥104M☉）在环分裂区周围表现出明显的集中，表明最近有一个卫星星系（M32）通过M31盘。
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