Cosmic-ray ionization in the lower atmosphere

摘要: The response of a pressurized argon-filled ionization chamber to charged particles in the cosmic radiation near 50°N geomagnetic latitude has been determined as function atmospheric depth from mountain altitudes sea level. γ contributions various readings were subtracted out by utilizing concurrent determinations γ-ray energy spectra obtained with scintillation spectrometer. Conversion relative absolute free air is accomplished normalizing mean reading at level calculated value 2.1±0.1 ion pairs cm−3/sec−1 atm−1 (STP), derived existing experimental data on muon, electron, and proton fluxes distributions. curve versus same shape that Millikan 1932, but significantly lower values. It inferred many present free-air ionization, primarily conducted higher altitudes, may be much 50% too high.