A study of twice-albedo electrons in the atmosphere

Measurements of the intensity of a vertical electron flux with an energy of 35-420 and 60-540 MeV were carried out at geomagnetic latitudes of 46 and 49 deg N in the atmosphere at altitudes of 14-35 km. The identification of the electrons against the proton background was based on the different manner in which these particles passed through the counter telescope; the latter included two lead absorbers in addition to a Cerenkov counter and scintillation counters. It is shown that linear extrapolation of the experimental data from 40 gxcm-2 to the atmosphere boundary yields a value of intensity of the vertical flux twice-albedo electrons equal to 910+-120 and 340+-40 electronsxm-2xsec-1xster-1 for 35-420 and 60-540 MeV, respectively. In actuality, the intensity of twice-albedo electrons varies nonlinearly with the depth of the atmosphere. It has been established that the intensity of the vertical flux of twice-albedo electrons at the atmosphere boundary is 1050+-150 and 390+-60 electronsxm-2xsec-1xster-1, respectively, at energy spectrum indices of α=1.6 (35-420 MeV) and 1.8 (60-540 MeV)