Constraining decaying dark matter with neutron stars

The amount of decaying dark matter, accumulated in the central regions in neutron stars together with the energy deposition rate from decays, may set a limit on the neutron star survival rate against transitions to more compact objects provided nuclear matter is not the ultimate stable state of matter and that dark matter indeed is unstable. More generally, this limit sets constraints on the dark matter particle decay time, tau(chi). We find that in the range of uncertainties intrinsic to such a scenario, masses (m(chi)/TeV) greater than or similar to 9 x 10(-4) or (m(chi)/TeV) greater than or similar to 5 x 10(-2) and lifetimes tau(chi) less than or similar to 10(55) s and tau(chi) less than or similar to 10(53) s can be excluded in the bosonic or fermionic decay cases, respectively, in an optimistic estimate, while more conservatively, it decreases tau(chi) by a factor greater than or similar to 10(20). We discuss the validity under which these results may improve with other current constraints. (C) 2015 The Authors. Published by Elsevier B.V.