Improved exclusion limit for light dark matter from $e^+e^-$ annihilation in NA64
Abstract
The current most stringent constraints for the existence of sub-GeV dark matter coupling to Standard Model via a massive vector boson were set by the NA64 experiment for the mass region MeV, by analyzing data from the interaction of 100-GeV electrons with an active thick target and searching for missing-energy events. In this work, by including production via secondary positron annihilation with atomic electrons, we extend these limits in the - MeV region by almost an order of magnitude, touching for the first time the dark matter relic density constrained parameter combinations. Our new results demonstrate the power of the resonant annihilation process in missing energy dark-matter searches, paving the road to future dedicated beam efforts.
Cite
@article{arxiv.2108.04195,
title = {Improved exclusion limit for light dark matter from $e^+e^-$ annihilation in NA64},
author = {Yu. Andreev and D. Banerjee and J. Bernhard and M. Bondi and V. Burtsev and A. Celentano and N. Charitonidis and A. Chumakov and D. Cooke and P. Crivelli and E. Depero and A. Dermenev and S. Donskov and R. Dusaev and T. Enik and A. Feshchenko and V. Frolov and A. Gardikiotis and S. Gerassimov and S. Gninenko and M. Hoesgen and M. Jeckel and V. Kachanov and A. Karneyeu and G. Kekelidze and B. Ketzer and D. Kirpichnikov and M. Kirsanov and V. Kolosov and I. Konorov and S. Kovalenko and V. Kramarenko and L. Kravchuk and N. Krasnikov and S. Kuleshov and V. Lyubovitskij and V. Lysan and L. Marsicano and V. Matveev and Yu. Mikhailov and L. Molina and D. Peshekhonov and V. Polyakov and B. Radics and R. Rojas and A. Rubbia and V. Samoylenko and H. Sieber and D. Shchukin and V. Tikhomirov and I. Tlisova and A. Toropin and A. Trifonov and P. Ulloa and B. Vasilishin and G. Vasquez and P. Volkov and V. Volkov},
journal= {arXiv preprint arXiv:2108.04195},
year = {2021}
}
Comments
Version accepted for publication as a Letter in Phys. Rev. D