The Richness of the Globular Cluster System of Ngc 3923: Clues to Elliptical Galaxy Formation
نویسندگان
چکیده
We present new data on the globular cluster system of the elliptical galaxy NGC 3923 which show that it has the most globular clusters per unit luminosity of any noncluster elliptical yet observed, with SN = 6:4 1:4. NGC 3923 is also among the brightest ellipticals outside of a galaxy cluster for which the number of globular clusters has been determined. Our observation of a large number of clusters per unit luminosity (high SN value) for a bright elliptical in a sparse environment is consistent with the suggestion of Djorgovski & Santiago that the number of globular clusters is a power law function of the luminosity with an exponent greater than one. We relate this higher speci c frequency of globular clusters in more luminous galaxies to other observations which indicate that the physical conditions within elliptical galaxies at the time of their formation were dependent on galaxy mass. Subject headings: galaxies: star clusters galaxies: formation galaxies: elliptical and lenticular 2
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Constraints on the Formation History of the Elliptical Galaxy Ngc 3923 from the Colors of Its Globular Clusters
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