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The globular cluster system around the low-luminosity S0 galaxy NGC 7457

S. Chapelon·V. Buat·D. Burgarella·M. Kissler-Patig
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Abstract

We investigate the globular cluster system around the low-luminosity S0 galaxy NGC 7457 with deep B, V, I photometry. From the V photometry the total number of globular clusters around the galaxy is estimated to be 178 +- 75. The specific frequency is estimated to be S_N = 2.7 +- 1.1 adopting M_V = -19.55 mag for the galaxy. We select 89 globular cluster candidates on the basis of their colors (B-I, V-I and B-V). The B-I and V-I color distributions are found unimodal with a mean metallicity [Fe/H] ~ -1. dex. Nevertheless the width of the B-I color distribution is found larger than that expected for a single population of globular clusters and is consistent with the presence of more than one population. If the latter is the case, the two peaks would not be detected in B-I because of the small statistics and/or a small difference in the mean metallicity of the two populations. No metal poor globular clusters similar to those of the Milky Way halo are detected around NGC 7457.

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S. Chapelon, V. Buat, D. Burgarella, M. Kissler-Patig. 1999-04-08. The globular cluster system around the low-luminosity S0 galaxy NGC 7457. https://arxiv.org/abs/astro-ph/9904095

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