It has been recently shown ( Tsiklauri & Viollier , 1998a ) that the matter concentration inferred from observed 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 .
It has been furthermore suggested ( Tsiklauri & Viollier , 1998a ) that the neutrino ball scenario may have an advantage that it could possibly explain the so-called ” blackness problem ” of the galactic center .
Here , we present a quantitative investigation of this statement , by calculating the emitted spectrum of Sgr A ^ { * } in the framework of standard accretion disk theory .