Search for hadronic decays of feebly-interacting particles at NA62

The NA62 collaboration Cortina Gil, Eduardo ; Jerhot, Jan ; Lurkin, Nicolas ; et al.
CERN-EP-2025-012, 2025.
Inspire Record 2877075 DOI 10.17182/hepdata.156981

The NA62 experiment at CERN has the capability to collect data in a beam-dump mode, where 400 GeV protons are dumped on an absorber. In this configuration, New Physics particles, including dark photons, dark scalars, and axion-like particles, may be produced in the absorber and decay in the instrumented volume beginning approximately 80 m downstream of the dump. A search for these particles decaying in flight to hadronic final states is reported, based on an analysis of a sample of $1.4 \times 10^{17}$ protons on dump collected in 2021. No evidence of a New Physics signal is observed, excluding new regions of parameter spaces of multiple models.

66 data tables

90% CL upper limit in dark photon coupling vs mass parameter space for combined di-lepton and hadronic final states, using bremsstrahlung production without the time-like form factor.

90% CL upper limit in dark photon coupling vs mass parameter space for combined di-lepton and hadronic final states, including mixing and bremsstrahlung production with a time-like form factor.

90% CL upper limit in dark scalar coupling vs mass parameter space for combined di-lepton and hadronic final states.

More…