Long-term (50 years) measurements of cosmic ray fluxes in the atmosphere

Since the middle of 1957 till present time the group of researchers of P.N. Lebedev Physical Institute of the Russian Academy of Sciences has carried out the regular balloon borne measurements of charged particle fluxes in the atmosphere. The measurements are performed at polar (northern and southern) and middle latitudes and cover the interval of heights from the ground level up to 30–35 km. Standard detectors of particles (gas-discharged counters) have been used. More than 80,000 measurements of cosmic ray fluxes in the atmosphere have been performed to the present time. In the data analysis the geomagnetic field and the Earth’s atmosphere are used as cosmic ray spectrometers.The main goals of observations are the investigations of galactic cosmic ray modulation in the heliosphere, solar cosmic ray generation and propagation, precipitation of energetic electrons from the Earth’s magnetosphere, study of the role of charged particles in the atmospheric processes. Now we have got a large amount of unique data on galactic and solar particles in the energy range of 0.1–20 GeV for the period of 50 years (1957–2007).In this paper, the main results obtained from the long-term measurements of charged particles in the atmosphere on the problems mentioned above are presented.