ИСТИНА

A new balloon experiment is proposed utilizing a small optical detector for the high energy (5·10^18-10^20 eV) extensive air showers registration via their Vavilov-Cherenkov radiation and the fluorescence light. The flights are planned to take place during the polar night period at an altitude up to 30 km above snow covered surface of Antarctica. This will allow to achieve high registration area (up to 600 km^2) and allow to measure the two shower optical components of the shower - Vavilov-Cherenkov radiation and fluorescence light by the same sensitive elements of the detector simultaneously. The reliable data about the energy spectrum and mass composition of primary cosmic rays in the energy region 5·10^18 - 5·10^19eV is also interesting in connection with the planned orbital experiments further extending measurements into ultra-high energy region.