Abstract
Thermal dark matter models with particle masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV production through the interaction mediated by a new vector boson, called the dark photon , in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With electrons on target collected during 2016–2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the couplings to photons for masses , and to exclude scalar and Majorana dark matter with the coupling for masses and .
- Received 9 July 2023
- Accepted 14 September 2023
DOI:https://doi.org/10.1103/PhysRevLett.131.161801
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society