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arXiv · 1112.2821

Faint Companions of Isolated 2MIG Galaxies

V. E. Karachentseva·I. D. Karachentsev·O. V. Melnyk
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Abstract

We present the results of a search for companions around the isolated galaxies from the 2MIG catalog. Among 3227 2MIG galaxies we detected 125 objects with a total of 214 neighbors having radial velocity differences of Delta V < 500 km/s and projected separations of R_p < 500 kpc relative to the 2MIG galaxies. The median luminosity of the companions is 1/25 of the luminosity of catalog galaxies, which has little effect on the dynamic isolation of the latter. The median ratio of the orbital mass to the K-luminosity determined from 60 companions of E and S0 2MIG galaxies, 63 M_sun/L_sun, is signficantly greater than that found from the spiral galaxy companions (17 M_sun/L_sun). We note that a fraction of 2MIG galaxies with companions may be a part of low-contrast diffuse structures: clouds and filaments.

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V. E. Karachentseva, I. D. Karachentsev, O. V. Melnyk. 2011-12-13. Faint Companions of Isolated 2MIG Galaxies. https://doi.org/10.1134/s1990341311040018

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