On the X-ray emission of the low-mass galaxy groups
نویسنده
چکیده
It is shown that the low-mass groups obey the Lx ∼ σ 4 v law deduced for galaxy clusters. The impression of the more shallow slope of the Lx − σv correlation for groups is created not by enhanced X-ray emission, but by underestimation of the radial velocity dispersion of some groups. Subject headings: galaxies: clusters : general – X-rays: galaxies
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