The structure of eight globular clusters
Autor: | N. A. Bahcall, M. A. Hausman |
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Rok vydání: | 1977 |
Předmět: |
Physics
Stellar mass Astronomy Astronomy and Astrophysics Star count Astrophysics Horizontal branch Star cluster Space and Planetary Science Intermediate-mass black hole Globular cluster Cluster (physics) Astrophysics::Solar and Stellar Astrophysics Stellar black hole Astrophysics::Galaxy Astrophysics |
Zdroj: | The Astrophysical Journal. 213:93 |
ISSN: | 1538-4357 0004-637X |
Popis: | Star counts on short-exposure plates are presented for eight globular clusters. The data are given to several limiting magnitudes for each cluster. Projected radial distributions are determined from the star counts; no significant segregation is observed among the distributions to various limiting magnitudes. The structural parameters of the clusters (core radii and concentration factors) are determined from best-fitting King curves to the observed distributions. The central densities, total masses, central escape velocities, and relaxation times are also calculated. NGC 6093 (M80) and NGC 7099 (M30) have dense compact stellar cores, similar to the established globular X-ray sources. Upper limits are given for the masses of possible central black holes in the eight clusters. |
Databáze: | OpenAIRE |
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