Search for vector mediator of dark matter production in invisible decay mode

2017/10/31 by NA64 Collaboration, D. Banerjee, V.E. Burtsev +62 · 2 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Axion #Dark Matter and Cosmic Phenomena #Dark matter #Dark photon #Electron #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Photon #Physics #Production (economics) #Quantum mechanics #Scalar (mathematics) #hep-ex #hep-ph

paper · pdf · doi:10.1103/physrevd.97.072002

published as Phys. Rev. D 97, 072002 (2018) · 22 pages, 17 figures, version accepted for publication in PRD

openalex created_date 2017/10/20 · arxiv created 2018/03/22 · openalex publication_date 2018/04/04 · arxiv updated 2018/04/11 · openalex updated_date 2026/08/05

Abstract

A search is performed for a new sub-GeV vector boson (A^\ensuremath') mediated production of dark matter (\ensuremathχ) in the fixed-target experiment, NA64, at the CERN SPS. The A^\ensuremath', called dark photon, can be generated in the reaction e^\ensuremath-Z\ensuremath→e^\ensuremath-ZA^\ensuremath' of 100 GeV electrons dumped against an active target followed by its prompt invisible decay A^\ensuremath'\ensuremath→\ensuremathχ\ensuremathχ. The experimental signature of this process would be an event with an isolated electron and large missing energy in the detector. From the analysis of the data sample collected in 2016 corresponding to 4.3\ifmmode×\else\texttimes\fi10¹⁰ electrons on target no evidence of such a process has been found. New stringent constraints on the A^\ensuremath' mixing strength with photons, 10^\ensuremath-5\ensuremath\lesssim\ensuremathε\ensuremath\lesssim10^\ensuremath-2, for the A^\ensuremath' mass range m_A^\ensuremath'\ensuremath\lesssim1 GeV are derived. For models considering scalar and fermionic thermal dark matter interacting with the visible sector through the vector portal the 90% C.L. limits 10^\ensuremath-11\ensuremath\lesssimy\ensuremath\lesssim10^\ensuremath-6 on the dark-matter parameter y=\ensuremathε²\ensuremathα_D(\fracm_\ensuremathχm_A^\ensuremath')⁴ are obtained for the dark coupling constant \ensuremathα_D=0.5 and dark-matter masses 0.001\ensuremath\lesssimm_\ensuremathχ\ensuremath\lesssim0.5 GeV. The lower limits \ensuremathα_D\ensuremath\gtrsim10^\ensuremath-3 for pseudo-Dirac dark matter in the mass region m_\ensuremathχ\ensuremath\lesssim0.05 GeV are more stringent than the corresponding bounds from beam dump experiments. The results are obtained by using exact tree level calculations of the A^\ensuremath' production cross sections, which turn out to be significantly smaller compared to the one obtained in the Weizs"acker-Williams approximation for the mass region m_A^\ensuremath'\ensuremath\gtrsim0.1 GeV.

Citations

• Can annihilating dark matter be lighter than a few GeVs?
• Presentation of search results: theCLstechnique
• Final report of the E821 muon anomalous magnetic moment measurement at BNL
• A theory of dark matter
• Geant4 developments and applications
• Observing a light dark matter beam with neutrino experiments
• The Low-Energy Frontier of Particle Physics
• Review of Multibody Charm Analyses

Cited by

• Dark Matter Search in Missing Energy Events with NA64
• Serendipity in dark photon searches
• Examining the origin of dark matter mass at colliders

Related

• Search for Light Dark Matter with NA64 at CERN
• Search for invisible decays of sub-GeV dark photons in missing-energy events at the CERN SPS
• Probing invisible vector meson decay mode with hadronic beam in the NA64 experiment at SPS/CERN
• Test of vector portal with dark fermions in the charge-exchange reactions in the NA64 experiment at CERN SPS
• Shedding light on Dark Sectors with high-energy muons at the NA64 experiment at the CERN SPS