Albedo factors of 123, 320, 511, 662 and 1115 keV gamma photons in carbon, aluminium, iron and copper

Experimental measurements to study the variation of albedo factors in carbon, aluminium, iron and copper are carried out using gamma photons obtained from Co-57, Ba-133, Na-22, Cs-137 and Zn-65. The back-scattered photons from the samples are detected by a 3 '' x 3 '' NaI(Tl) scintillation detector placed at a backscattering angle of 180 degrees. The variation of number albedo (A(N)), energy albedo (A(E)) and dose albedo (A(D)) as a function of source energy and atomic number (Z) is studied. The experimentally obtained, response corrected variation of multiple scattered photons as a function of target thickness is compared with the Monte Carlo simulation using MCNP code and are in good agreement.