Study of solar activity by measuring cosmic rays with a water Cherenkov detector

Gadolinium study for a water Cherenkov detector

Modification of large water Cherenkov detectors by addition of gadolinium has been proposed. The large cross section for neutron capture on Gd will greatly improve the sensitivity to antielectron neutrinos from supernovae and reactors. A five-year project to build and develop a prototype detector based on Super-Kamiokande (SK) has started. We are performing various studies, including a material...

First Study of Neutron Tagging with a Water Cherenkov Detector

A first study of neutron tagging is conducted in Super–Kamiokande, a 50,000-ton water Cherenkov detector. The tagging efficiencies of thermal neutrons are evaluated in a 0.2 % GdCl3-water solution and pure water. They are determined to be, respectively, 66.7 % for events above 3 MeV and 20 % with corresponding background probabilities of 2 × 10 and 3 × 10. This newly developed technique may ena...

Callibration of a homemade 4-fold Water Cherenkov Detector array, by detection of EAS events

The time structure of Cherenkov images generated by TeV γ-rays and by cosmic rays

Preprint submitted to Elsevier Preprint 5 February 2008 The time profiles of Cherenkov images of cosmic-ray showers and of γ-ray showers are investigated, using data gathered with the HEGRA system of imaging atmospheric Cherenkov telescopes during the 1997 outbursts of Mrk 501. Photon arrival times are shown to vary across the shower images. The dominant feature is a time gradient along the maj...

callibration of a homemade 4-fold water cherenkov detector array, by detection of eas events