We present the prospects for detection of KK-axions using a large volume spherical TPC through natural decay to two gammas. The higher excited mass states of this axion model allows to reach densities which could be detectable by this method. We show
the capability of this detector to detect 2-prong events coming from rest-mass axion decays and we provide efficiencies obtained under some gas mixtures and pressure conditions. The sensitivity limit of a future experiment with existing detectors geometry has been estimated for the case of zero background limit.
This is the mini-review on Dark Matter in the 2012 edition of the Particle Data Groups Review of Particle Properties. After briefly summarizing the arguments in favor of the existence of Dark Matter, we list possible candidates, ranging in mass from
a fraction of an eV (e.g., axions) to many solar masses (e.g., primordial black holes), and discuss ways to detect them. The main emphasis is on Weakly Interacting Massive Particles (WIMPs). A large international effort is being made to detect them directly, or else to detect their annihilation products. We explain why we consider all claims to have established a positive signal for WIMPs in either direct or indirect detection to be premature. We also introduce the concept of a {it WIMP safe} minimal mass; below this mass, the interpretation of a given direct search experiment depends strongly on the tail of the WIMP velocity distribution and/or on the experimental energy resolution.
