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The Globular Cluster Systems of NGC 1400 and NGC 1407

K. M. Perrett·D. A. Hanes·S. T. Butterworth·JJ Kavelaars·D. Geisler·W. E. Harris
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Abstract

The two brightest elliptical galaxies in the Eridanus A group, NGC 1400 and NGC 1407, have been observed in both the Washington T_1 and Kron-Cousins I filters to obtain photometry of their globular cluster systems (GCSs). This group of galaxies is of particular interest due to its exceptionally high M/L value, previously estimated at ~3000h, making this cluster highly dark-matter-dominated. NGC 1400's radial velocity (549 km/s) is extremely low compared to that of the central galaxy of Eridanus A (NGC 1407 with $v_\odot$ = 1766 km/s) and the other members of the system, suggesting that it is a foreground galaxy projected by chance onto the cluster. Using the shapes of the globular cluster luminosity functions, however, we derive distances of 17.6 +/- 3.1 Mpc to NGC 1407 and 25.4 +/- 7.0 Mpc to NGC 1400. These results support earlier conclusions that NGC 1400 is at the distance of Eridanus A and therefore has a large peculiar velocity. Specific frequencies are also derived for these galaxies, yielding values of S_N = 4.0 +/- 1.3 for NGC 1407 and S_N = 5.2 +/- 2.0 for NGC 1400. In this and other respects, these two galaxies have GCSs which are consistent with those observed in other galaxies.

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K. M. Perrett, D. A. Hanes, S. T. Butterworth, JJ Kavelaars, D. Geisler, W. E. Harris. 1996-11-06. The Globular Cluster Systems of NGC 1400 and NGC 1407. https://doi.org/10.1086/118309

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