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arXiv · astro-ph/0504335

The Globular Cluster Content of Maffei 1

T. J. Davidge·Sidney van den Bergh
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Abstract

Near-infrared images have been used to search for bright globular clusters near the center of the elliptical galaxy Maffei 1. The number of objects in various radial intervals from the center of Maffei 1 are compared with the number density of sources in two control fields, and we find an excess of 31 +/- 11 objects with K between 16.6 and 18.0 in an annulus between 20 and 90 arcsec from the galaxy center. At radii in excess of 90 arcsec the ability to find clusters is frustrated by statistical noise in the foreground star population. It is demonstrated that the globular clusters located within 90 arcsec of the center of Maffei 1 span a range of near-infrared colors that are at least as great as that which is seen among M31 clusters; some of the clusters appear to have colors that are consistent with them being very young. The specific globular cluster frequency within 90 arcsec of the center of Maffei 1 is S_N = 1.3 +/- 0.6 if the distance modulus is 28.1 +/- 0.2 and A_V = 4.7 +/- 0.2. The specific cluster frequency of Maffei 1 is thus similar to that of other nearby field elliptical galaxies.

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T. J. Davidge, Sidney van den Bergh. 2005-04-14. The Globular Cluster Content of Maffei 1. https://doi.org/10.1086/430367

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