Examination of cosmic radiation with a low budget sonde

During one school year 5 high-school graduates and their teacher developed a balloon sonde to examine the physical properties of the stratosphere. On its rise in an altitude of 28 km, the sonde collected numberless pictures and data with respect to pressure, temperature and cosmic radiation. It was possible to prove the exponential decrease of pressure in respect to altitude. The increase in temperature within the stratosphere due the interaction between ultraviolet light and ozone could also be proved. The analysis of the cosmic radiation shows the sonde passed a maximum of a cosmic ray air shower in an altitude of 17,8 km. Calculations resulted in a primary particle of 10,3 GeV, which caused the cosmic ray air shower observed by the sonde. (orig.)