Spherical Jeans analysis for dark matter indirect detection in dwarf spheroidal galaxies - impact of physical parameters and triaxiality

摘要: Dwarf spheroidal (dSph) galaxies are among the most promising targets for indirect detection of dark matter (DM) from annihilation and/or decay products. Empirical estimates their DM content—and hence magnitudes expected signals—rely on inferences stellar-kinematic data. However, various kinematic analyses can give different results and it is not obvious which reliable. Using extensive sets mock data sizes (mimicking ‘ultra-faint’ ‘classical’ dSphs) an MCMC engine, here we investigate biases, uncertainties, limitations based parametric solutions to spherical Jeans equation. For a variety functional forms tracer density profiles, as well orbital anisotropy profile, examine reliability astrophysicalJ- D-factors decay, respectively. large (N & 1000) samples typical dSphs, errors tend be dominated by systematics, reduced through use sufficiently general flexible forms. small . 100) ‘ultrafaints’, statistical uncertainties dominate systematic models less necessary. Finally, find that assumption symmetry bias J (by up factor few) when object mildly triaxial (axis ratiosb=a = 0:8,c=a 0:6). A concluding table summarises error budget biases sample considered. We also define optimal strategy would mitigate sensitivity priors other aspects