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arXiv · 0705.4037

An updated survey of globular clusters in M31. II Newly discovered bright and remote clusters

S. Galleti·M. Bellazzini·L. Federici·A. Buzzoni·F. Fusi Pecci
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Abstract

We present the first results of a large spectroscopic survey of candidate globular clusters located in the extreme outskirts of the nearby M31 galaxy. We obtained low resolution spectra of 48 targets selected from the XSC of 2MASS, as in Galleti et al. (2005). The observed candidates have been robustly classified according to their radial velocity and by verifying their extended/point-source nature from ground-based optical images. Among the 48 observed candidates clusters we found 5 genuine remote globular clusters. One of them has been already identified independently by Mackey et al. (2007), their GC1; the other four are completely new discoveries: B516, B517, B518, B519. The newly discovered clusters lie at projected distance 40 kpc<~R_p<~100 kpc from the center of M31, and have absolute integrated magnitude -9.5 40 kpc. At odds with the Milky Way, M31 appears to have a significant population of very bright globular clusters in its extreme outskirts.

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S. Galleti, M. Bellazzini, L. Federici, A. Buzzoni, F. Fusi Pecci. 2007-05-28. An updated survey of globular clusters in M31. II Newly discovered bright and remote clusters. https://doi.org/10.1051/0004-6361:20077788

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