CALCULATED RESPONSE OF AIR-WALL DOSIMETERS OR GEIGER-MUELLER TUBES TO MONO-ENERGETIC PHOTONS BETWEEN I AND IO MeV

摘要

The question of registering dose from weapon and reactor photons of 2 to 10 MeV energy has led to a study of the capability of conventional dosimeters and Geiger-Mueller tubes to respond accurately to these energies. Calculations of the response of thin and thick air-wall dosimeters have been made. The results are given as "efficiencies", or the ratio of the chamber response in charge per cubic centimeter in the dosimeter per incident photon fluence, to the same quantity in an ideal air wall chamber in electronic equilibrium. Stated in this way the re¬sults do not specifically refer to any type of chamber, but rather to interactions which result from normally incident photons. A very broad beam including scattered photons or an isotropic photon flux should give results approximately proportional to those computed.nThe cases are analyzed of l/l6-in. and l/8-in. air wall dosimeters under bombardment with these high energy photons, and also under bombardment with these photons plus the electron flux density coming from an air absorber of sufficient thickness to ensure primary to secondary radiation equilibrium.