The Spectroscopic and Photometric Study of a Star Cluster Sample in Andromeda Halo

Hongrui Gu; Zhou Fan; Bingqiu Chen; Xiaoying Pang; Juanjuan Ren; Ruizheng Jiang; Song Wang; Kefeng Tan; Nan Song; Chun Li; Jie Zheng; Gang Zhao; Wei Wang; Yuqin Chen; Jingkun Zhao; Haining Li; Yihan Song; Haibo Yuan; Ali Luo; Yujuan Liu; Yaqian Wu

arXiv · 2603.18151

The Spectroscopic and Photometric Study of a Star Cluster Sample in Andromeda Halo

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Abstract

Halo star clusters serve as vital tracers for the formation and evolution of the Andromeda galaxy. In this work, we present physical parameters for 29 M31 halo star clusters, derived from a combination of spectroscopic and photometric data. Low-resolution spectra were acquired using the BFOSC spectrograph on the NAOC Xinglong 2.16-m telescope. For the photometric analysis, we utilized uSC and vSAGE bands from the SAGE survey, complemented by archival data from GALEX(NUV, FUV), PAN-STARRS(grizy) and the 2MASS(JHK). Ages and metallicities were determined via ULySS (Vazdekis et al. and pegase-hr) SSP model and the Bruzual & Charlot (2003) (BC03) stellar population synthesis models. The derived parameters show good agreement with literature values. Notably, for three of these clusters, this study represents the first combined photometric and spectroscopic analysis.

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Hongrui Gu, Zhou Fan, Bingqiu Chen, Xiaoying Pang, Juanjuan Ren, Ruizheng Jiang, Song Wang, Kefeng Tan, Nan Song, Chun Li, Jie Zheng, Gang Zhao, Wei Wang, Yuqin Chen, Jingkun Zhao, Haining Li, Yihan Song, Haibo Yuan, Ali Luo, Yujuan Liu, Yaqian Wu. 2026-03-18. The Spectroscopic and Photometric Study of a Star Cluster Sample in Andromeda Halo. https://arxiv.org/abs/2603.18151

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