Speaker
David Osterman
(Brown University)
Description
We describe a new detector for dark matter searches by direct detection based upon the quantum evaporation of He atoms from a cold surface and their detection using field ionization. The single atom sensitivity of the field ionization array and the $<1$ meV binding energy of a He atom to the surface of liquid He open the door for the detection of dark matter particles with mass as low as $1$ MeV/c$^2$. When a dark matter particle collides with an atom in liquid He it produces phonons and rotons. When the rotons arrive at the surface they can evaporate a He atom, which can be detected by a field ionization array. This dense array of sharp, positively charged metal tips will ionize the He atoms in a strong electric field and accelerate them to a high kinetic energy. A calorimeter with a low heat capacity can easily measure the impact of even just one of these He ions. We will present the design of the proposed detector as well as the results of preliminary field ionization experiments.
Primary author
David Osterman
(Brown University)
Co-authors
Prof.
Derek Stein
(Brown University)
Prof.
George Seidel
(Brown University)
Prof.
Humphrey Maris
(Brown University)
