Half Life and Nuclear Reaction Cross Section Using Decay Spectroscopy

This project describes mainly the calculation of half lives of the observed gamma rays and production cross-sections for the nuclei produced in the nuclear reaction 150Nd at 15 MeV. Here, with the help of two known sources (133Ba and 152Eu) energy and efficiency calibrations were done. The efficiency havs been measured at two different distances of 3 and 15 cm from the detector and were compared. Using the energy calibration the photo peaks of various gamma rays produced in the reaction were analyzed and their areas were plotted against the time instant at which they were taken during the experiment, compared to the time t=0. Half lives were calculated for the obtained gamma rays and were assigned to different nuclei corresponding to the half life values. Three nuclei were identified as the product of the nuclear reaction, viz., 150Pm, 149Pm and 149Nd. A set of gamma rays were identified which belong to 150Sm nucleus, produced from the decay of 150Pm, but shows higher lifetime values compared to that of the ground states of 150Pm. The absolute cross-sections were calculated by using the obtained area, their abundance, efficiency and other required parameters.