The Imaging Atmospheric Cherenkov technique has opened up previously unexplored windows for the study of astrophysical radiation sources in very high-energy (VHE) regime and is playing an important role discovery characterization VHE gamma-ray emitters. However, even most powerful sources, data collected by Telescopes (IACTs) are heavily dominated overwhelming background due to cosmic-ray nucle...

We review the recent developments in the field of ultrafast Cherenkov fiber lasers. Two essential properties of such laser systems - broad wavelength tunability and high efficiency of Cherenkov radiation wavelength conversion are discussed. The exceptional performance of the Cherenkov fiber laser systems are highlighted - dependent on the realization scheme, the Cherenkov lasers can generate th...

The Auger Muon Infill Ground Array (AMIGA) is part of the AugerPrime upgrade Pierre Observatory. It consists particle counters buried 2.3 m underground next to water-Cherenkov stations that form 23.5 km2 large infilled array. reduced distance between detectors in this denser area allows lowering energy threshold for primary cosmic ray reconstruction down about 1017 eV. At depth electromagnetic ...

Suitably designed optical fibers are shown to offer a powerful tool for functional brain mapping, facilitating the detection of Cherenkov radiation generated by relativistic positrons from positron-emitting radionuclides. Fiber probes support a low-loss delivery of the high-intensity short-wavelength part of the Cherenkov spectrum, which is strongly absorbed by biotissues, and lower the thresho...