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تسجيل مستخدم جديدDark matter concentration in the galactic center
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It is shown that the matter concentration observed through stellar motion at the galactic center (Eckart & Genzel, 1997, MNRAS, 284, 576 and Genzel et al., 1996, ApJ, 472, 153) is consistent with a supermassive object of $2.5 times 10^6$ solar masses composed of self-gravitating, degenerate heavy neutrinos, as an alternative to the black hole interpretation. According to the observational data, the lower bounds on possible neutrino masses are $m_ u geq 12.0$ keV$/c^2$ for $g=2$ or $m_ u geq 14.3$ keV$/c^2$ for $g=1$, where $g$ is the spin degeneracy factor. The advantage of this scenario is that it could naturally explain the low X-ray and gamma ray activity of Sgr A$^*$, i.e. the so called blackness problem of the galactic center.
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