Constraining the distribution of dark matter in inner galaxy with
  indirect detection signal: The case of tentative 130 gev {\gamma}-ray line
  The dark matter distribution in the very inner region of our Galaxy is still
in debate. In the N-body simulations a cuspy dark matter halo density profile
is favored. Several dissipative baryonic processes however are found to be able
to significantly flatten dark matter distribution and a cored dark matter halo
density profile is possible. The baryons dominate the gravitational potential
in the inner Galaxy, hence a direct constrain on the abundance of the dark
matter particles is rather challenging. Recently, a few groups have identified
a tentative 130 GeV line signal in the Galactic center, which could be
interpreted as the signal of the dark matter annihilation. With current 130 GeV
line data and adopting the generalized Navarro-Frenk-White profile of the dark
matter halo, for local dark matter density \rho_0=0.4 GeV cm^{-3} and r_s=20
kpc we obtain a 95% confidence level lower (upper) limit on the inner slope of
dark matter density distribution \alpha = 1.06 (the cross section of dark
matter annihilation into gamma-rays <\sigma v >_{\chi\chi -> \gamma\gamma}=
1.3\times 10^{-27} cm^3 s^{-1}). Such a slope is consistent with the results of
some N-body simulations, and if the signal is due to dark matter, suggests that
baryonic processes may be unimportant.
