http://arxiv.org/abs/1604.08206
We show that a two-excitation process in superfluid helium, combined with sensitivity to meV energy depositions, can probe dark matter down to the ~keV warm dark matter mass limit. This mass reach is three orders of magnitude below what can be probed with ordinary nuclear recoils in helium at the same energy resolution. The kinematics of the process requires the two athermal excitations to have nearly equal and opposite momentum, potentially providing a built-in coincidence mechanism for controlling backgrounds.
K. Schutz and K. Zurek
Fri, 29 Apr 16
11/57
Comments: 5 pages, 2 figures