TY  - JOUR
AU  - Caputo, A.
AU  - Esposito, A.
AU  - Polosa, A. D.
PY  - 2019
DA  - 2019//
TI  - Sub-MeV dark matter and the Goldstone modes of superfluid helium
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 116007
EP  - 6pp
VL  - 100
IS  - 11
PB  - Amer Physical Soc
AB  - We show how a relativistic effective field theory for the superfluid phase of 4 He can replace the standard methods used to compute the production rates of low-momentum excitations due to the interaction with an external probe. This is done by studying the scattering problem of a light dark matter particle in the superfluid and comparing to some existing results. We show that the rate of emission of two phonons, the Goldstone modes of the effective theory, gets strongly suppressed for sub-MeV dark matter particles due to a fine cancellation between two different tree-level diagrams in the limit of small exchanged momenta. This phenomenon is found to be a consequence of the particular choice of the potential felt by the dark matter particle in helium. The predicted rates can vary by orders of magnitude if this potential is changed. We prove that the dominant contribution to the total emission rate is provided by excitations in the phonon branch. Finally, we analyze the angular distributions for the emissions of one and two phonons and discuss how they can be used to measure the mass of the hypothetical dark matter particle hitting the helium target.
SN  - 2470-0010
UR  - https://arxiv.org/abs/1907.10635
UR  - https://doi.org/10.1103/PhysRevD.100.116007
DO  - 10.1103/PhysRevD.100.116007
LA  - English
N1  - WOS:000501488800008
ID  - Caputo_etal2019
ER  -