During the 10 years of existence of the HEGRA Cherenkov telescopes a large fraction of the time was spent on the observation of BL Lac objects. Here we present an overview of some of the main results and give an outlook on the next generation of Cherenkov telescopes.

Cherenkov radiation is induced when charged particles travel through dielectric media (such as biological tissue) faster than the speed of light through that medium. Detection of this radiation or excited luminescence during megavoltage external beam radiotherapy (EBRT) can allow emergence of a new approach to superficial dose estimation, functional imaging, and quality assurance for radiation ...

We investigate the development of electromagnetic cascades in ice using a GEANT Monte Carlo simulation. We examine the Cherenkov pulse that is generated by the charge excess that develops and propagates with the shower. This study is important for the RICE experiment at the South Pole, as well as any test beam experiment which seeks to measure coherent Cherenkov radiation from an electromagneti...

Kuzmichev recently showed that use of phase velocity rather than group velocity for Cherenkov light signals and pulses from calibration lasers in high-energy neutrino telescopes leads to errors in track reconstruction and distance measurement. We amplify on his remarks and show that errors for four cases of interest to AMANDA, IceCube, and RICE (radio Cherenkov detector) are negligibly small.

The distinction of secondary particles in extensive air showers, specifically muons and electrons, is one the requirements to perform a good measurement composition primary cosmic rays. We describe two methods for pulse shape detection discrimination electrons implemented on FPGA. One uses an artificial neural network (ANN) algorithm; other exploits correlation approach based finite impulse res...

Cherenkov telescope observations at zenith angles > 70o are capable of providing large collection areas. This improves the detection efficiency for photons at very high energies. In order to understand the telescope’s performance extended Monte Carlo studies have been made taking the first HEGRA Cherenkov telescope CT1 as an example. First results of these studies will be presented.

The H.E.S.S. experiment (High Energy Stereoscopic System) is a new generation atmospheric Cherenkov detector measuring high-energy (> 100 GeV) gamma radiation from the Universe. This paper briefly explains the imaging Cherenkov technique and describes the H.E.S.S. project and its current status.

We investigate the development of electromagnetic cascades in ice using a GEANT Monte Carlo simulation. We examine the Cherenkov pulse that is generated by the charge excess that develops and propagates with the shower. This study is important for the RICE experiment at the South Pole, as well as any test beam experiment which seeks to measure coherent Cherenkov radiation from an electromagneti...