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 $$1.4 \times 10^{17}$$ 1.4 × 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.

A bstract: Results from the study of the rare decays $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} $$ K + → π + ν ν ¯ , K ⁺ → π ⁺ μ ⁺ μ ⁻ and K ⁺ → π ⁺ γγ at the NA62 experiment at CERN are interpreted in terms of improved limits for $$ \mathcal{B}\left({K}^{+}\to {\pi}^{+}X\right) $$ B K + → π + X and coupling parameters of hidden-sector models, where X is a mediator. World-leading limits are achieved for dark photon, dark scalar and axion-like particle models.

The multipurpose detector complex of the Tien Shan mountain station of LPI provides the means to carry out studies in the various fields of experimental geophysics. The detectors of cosmic ray particles present at the station can be used for continuous monitoring of different types of background radiation: of the current flux of (1–100) GeV cosmic ray hadrons, of thermal neutrons in the surrounding environment, and of the gamma-rays with energy (30–3000) keV. Special system of the high altitude detectors permits to register the electrons accelerated up to several tens and hundreds of MeV by the atmospheric electric fields in thunderclouds, as well as the gamma radiation generated by these particles. A combination of diverse radiation receivers can be used for simultaneous detection of the time profiles of lightning emission in the different wave ranges of electromagnetic spectrum, starting from near ultraviolet and up to (1–30) MHz radio-waves, as well as of the electromagnetic pulses propagating over the global earth-ionosphere waveguide in the VLF, (1–10) kHz, and SLF, (1–10) Hz, frequency ranges. An underground complex of the neutron, gamma-ray, and acoustic detectors placed in a borehole at an up to \({\sim}\)300-m depth below the surface of the ground is used for detection of the various signals of geophysical origin, including those which could be triggered by interaction of penetrative cosmic ray particles with the matter of the earth’s crust. Perspectives of geophysical experiments at the Tien Shan station are discussed here together with application opportunity of their results to various problems of the space physics, of the physics of atmospheric discharge and lightning development, of environmental monitoring, and of the monitoring of seismic processes for the purpose of timely earthquake forecast.

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