We present Two Micron All Sky Survey JHK s photometry for 913 star clusters and candidates in the field of M31, which are selected from the latest Revised Bologna Catalog of M31 globular clusters (GCs) and candidates. The photometric measurements in this paper supplement this catalog, and provide the most comprehensive and homogeneous photometric catalog for M31 GCs in the JHK s bandpasses. In general, our photometry is consistent with previous measurements. The globular cluster luminosity function (GCLF) peaks for the confirmed GCs derived by fitting a t 5 distribution using the maximum likelihood method are , , and , all of which agree well with previous studies. The GCLFs are different between metal-rich (MR) and metal-poor (MP), and between inner and outer subpopulations, as MP clusters are fainter than their MR counterparts and the inner clusters are brighter than the outer ones, which confirm previous results. The NIR colors of the GC candidates are on average redder than those of the confirmed GCs, which leads to an obscure bimodal distribution of color indices. The relation of (V – K s)0 and metallicity shows a notable departure from linearity, with a shallower slope toward the redder end. The color-magnitude diagram (CMD) and color-color diagram show that many GC candidates are located out of the evolutionary tracks, suggesting that some of them may be false M31 GC candidates. The CMD also shows that the initial mass function of M31 GCs covers a large range, and the majority of the clusters have initial masses between 103 and 106 M ☉.
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机译：我们提出了M31的913个星团和M31领域的候选物的两微米全天候JHK光度法，这些测光选自最新的M31球状星团（GC）和候选者的修订的博洛尼亚目录。本文中的光度测量补充了该目录，并为JHK的带通量中的M31 GC提供了最全面，最均匀的光度目录。通常，我们的光度法与以前的测量结果一致。通过使用最大似然方法拟合t 5分布得出的已确认GC的球状星团发光度函数（GCLF）峰分别为，和，所有这些都与以前的研究非常吻合。 GCLF在富金属（MR）和贫金属（MP）之间以及内部和外部子种群之间有所不同，因为MP簇比其MR对应者更暗，内部簇比外部簇更亮，这证实了先前的结果。 GC候选物的NIR颜色平均比已确认GC的颜色更红，这导致颜色指数的双峰分布模糊。 （V – K s）0与金属度的关系显示出与线性度的显着偏离，向红端的斜率较小。色度图（CMD）和色色图显示，许多GC候选物位于进化轨道之外，这表明其中一些可能是错误的M31 GC候选物。 CMD还表明，M31 GC的初始质量函数覆盖范围很广，大多数簇的初始质量在103和106 M between之间。
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