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The observation of cosmic sub-PeV gamma rays from the Crab Nebula opens up the possibility of testing cosmic ray photon transparency at the multi-hundred-TeV scale. Assuming no deviation from a source gamma-ray emission due to accelerated electron inverse-Compton scattering, higher event energies can extend constraints on the effects of new physics; we consider oscillation between gamma rays and axions, plus attenuation effects from gamma-ray absorption in the case of dark photon dark matter. Combining the recent ASγ and HAWC sub-PeV data with earlier MAGIC and HEGRA data, axionlike particles are most constrained in the 2×10-7-6×10-7 eV mass range, where the coupling gaγγ is constrained to be below 1.8×10-10 GeV-1. Direct scattering from dark photon dark matter limits kinetic mixing ε≲10-3 for masses between 0.01 and 1 eV. [ABSTRACT FROM AUTHOR]

The interaction of the standard model's particles with the axionic dark matter field may generate oscillating nuclear electric dipole moments (EDMs), oscillating nuclear Schiff moments, and oscillating nuclear magnetic quadrupole moments (MQMs) with a frequency corresponding to the axion's Compton frequency. Within an atom or a molecule an oscillating EDM, Schiff moment, or MQM can drive transitions between atomic or molecular states. The excitation events can be detected, for example, via subsequent fluorescence or photoionization. Here we calculate the rates of such transitions. If the nucleus has octupole deformation or quadrupole deformation, then the transition rate due to the Schiff moment and MQM can be up to 10-16 transition per molecule per year. In addition, an MQM-induced transition may be of M2-type, which is useful for the elimination of background noise since M2-type transitions are suppressed for photons. [ABSTRACT FROM AUTHOR]

We present the improved constraints on couplings of solar axions and more generic bosonic dark matter particles using 737.1 kg days of data from the CDEX-1B experiment. The CDEX-1B experiment, located at the China Jinping Underground Laboratory, primarily aims at the direct detection of weakly interacting massive particles using a p-type point-contact germanium detector. We adopt the profile likelihood ratio method for analysis of data in the presence of backgrounds. An energy threshold of 160 eV was achieved, much better than the 475 eV of CDEX-1A with an exposure of 335.6 kg days. This significantly improves the sensitivity for the bosonic dark matter below 0.8 keV among germanium detectors. Limits are also placed on the coupling gAe < 2.48 × 10-11 from Compton, bremsstrahlung, atomic-recombination, and deexcitation channels and geffAN × gAe < 4.14 × 10-17 from a 57Fe M1 transition at 90% confidence level. [ABSTRACT FROM AUTHOR]