A study on the internal Bremsstrahlung of Cs137

The internal bremsstrahlung spectrum accompanying beta decay in Cs137 has been measured using the magnetic deflection method. The geometry was chosen such that NaI(Tl) crystal is well shielded from the external bremsstrahlung produced by the beta particles in the pole pieces of the magnet. The pileup is corrected for by graphical integration. The theoretical spectra of KUB, Lewis and Ford, and Chang and Folkoff is compared with our experimental spectrum. The agreement between measurement and theory is poor throughout the energy range in the present investigation, though the experimental points are closer to those in theory of Chang and Folkoff. When the pileup was estimated by graphical integration, the error was 5 to 8 percent and was less than 10 percent at all energy ranges. (Author)