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Description
This table contains a catalog of 422 galaxies with published measurements of their globular cluster (GC) populations. Of these, 248 are E galaxies, 93 are S0 galaxies, and 81 are spirals or irregulars. Among various correlations of the total number of GCs with other global galaxy properties, the authors find that the number of globular clusters N<sub>GC</sub> correlates well though nonlinearly with the dynamical mass of the galaxy bulge M<sub>dyn</sub> = 4 sigma _e_<sup>2</sup> R<sub>e</sub>/G, where sigma<sub>e</sub> is the central velocity dispersion and R<sub>e</sub> the effective radius of the galaxy light profile. In their paper, the authors also present updated versions of the GC specific frequency S<sub>N</sub> and specific mass S<sub>M</sub> versus host galaxy luminosity and baryonic mass. These graphs exhibit the previously known U-shape: highest S<sub>N</sub> or S<sub>M</sub> values occur for either dwarfs or supergiants, but in the mid-range of galaxy size (10<sup>9</sup> - 10<sup>10</sup> L<sub>sun</sub>) the GC numbers fall along a well-defined baseline value of S<sub>N</sub> ~= 1 or S<sub>M</sub> = 0.1, similar among all galaxy types. Along with other recent discussions, the authors suggest that this trend may represent the effects of feedback, which systematically inhibited early star formation at either very low or very high galaxy mass, but which had its minimum effect for intermediate masses. Their results strongly reinforce recent proposals that GC formation efficiency appears to be most nearly proportional to the galaxy halo mass M<sub>halo</sub>. The mean "absolute" efficiency ratio for GC formation that the authors derive from the catalog data is M<sub>GCS</sub>/M<sub>halo</sub> = 6 x 10<sup>-5</sup>. They suggest that the galaxy-to-galaxy scatter around this mean value may arise in part because of differences in the relative timing of GC formation versus field-star formation. Finally, they find that an excellent empirical predictor of total GC population for galaxies of all luminosities is N<sub>GC</sub> ~ (R<sub>e</sub> sigma<sub>e</sub>)<sup>1.3</sup>, a result consistent with fundamental plane scaling relations. This table was created by the HEASARC in February 2014 based on an electronic version of Table 1 from the reference paper which was obtained from the ApJ web site. A duplicate entry for NGC 4417 was removed in June 2019. This is a service provided by NASA HEASARC .
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