Studies on relaxation length of wood by method of gamma radiation

Abstract

Relaxation lengths of different types of wood were determined using gamma radiation from 60Co source. Results show that oxystigma (Oxystigma spp) has the highest relaxation length of 23.810 cm, while mangrove (Rhizophora spp) has the least relaxation length of 1.247 cm. A mathematical model has been developed for the prediction or determination of density (r) variation of wood with relaxation length. A good agreement (greater than 80%) was observed between the measured values and the predicted ones. With proper choice of the thickness of wood from theoretical evaluation, it was observed that Mangrove (Hard Wood) with thickness of 120 cm almost completely attenuate gamma ray energy in the range 0.1 Mev to 1.836 Mev.

Keywords: relaxation Length, wood, and gamma radiation

Nigerian Journal of Physics Vol. 17, 2005: 108-112