Superheavy dark matter can satisfy the observed dark matter abundance if the stability condition is fulfilled. Here, we propose a new Abelian gauge symmetry U(1)H for the stability of superheavy dark matter as the electromagnetic gauge symmetry to the electron. The new gauge boson associated with U(1)H contributes to the effective number of relativistic degrees of freedom in the universe as dark radiation, which has been recently measured by several experiments, e.g., PLANCK. We calculate the contribution to dark radiation from the decay of a scalar particle via the superheavy dark matter in the loop. Interestingly enough, this scenario will be probed by a future LHC run in the invisible decay signatures of the Higgs boson.
Bibliographical noteFunding Information:
This work is supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology NRF-2013R1A1A2061561 (JC), NRF-2013R1A1A2064120 (SC). We appreciate APCTP for its hospitality during completion of this work.
© 2014, The Korean Physical Society.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)