Deuterium - Deuterium Fusion Reaction Yield Of High-energy ¦Ã-ray Experiments

Nuclear reactions among light nuclei at low energies have long been recognized as being of fundamental importance to many areas of basic and applied physics. The study of D(d, y)4He radiative capture reactions at low energies is very important in the two areas of fusion energy and astrophysics. In the area of fusion energy, one can diagnose the high temperature of deuterium through measuring the high energy y -rays emitted from the reactions. In the area of astrophysics, this reaction is very important also in the primordial nucleosynthesis process in the famous Big- Bcng Model.Because the cross section of D(d, y)4He reaction is very small, and the intensity of neutrons emitted from its concomitant D(d, n)3He reaction is 107 times as stronger as the high energy Y -rays, the experimental measurement of high energy -rays is very difficult. While the background of cosmic rays is very big also.The project and development of our study of D(d, )4He reactions at low energies is depicted in this Doctor' s thesis. And a test experiment has been finished at Ed=300 keV with both thick and thin deuterium-loaded titanium targets. Based on this experiment, the detailed program of study work will be made. Furthermore, we will discuss the difficulties that maybe occur in the future measurement of this reaction at lower energies.For the very small yields of high energy v -rays and the serious background of neutrons and cosmic rays, a big NaI-Plastic anti-Compton spectrometer has been employed and the method of the time of flight (TOF) has been used.The efficiency of the Nal detector have been determined by the calculation using Mont-Carlo code (MNCP)and normalized by the experiment with 6.13MeV and 11.67 MeV -rays emitted from the 19F(p, a )16O and "B(p, )12 reactions, respectively. The efficiency includes the total energy peak, single escape and double escape peaks. The background was subtracted by our fitting method.Thick and thin D2 targets were measured, the branching ratios of D(d, Y )4He andD(d,p)T are /P= (1.064 + 0.266) 10-7 and /P= (1.104 0.276) 10-7 for thick and thin targets, respectively. The cross sections are 2.47 nb for the thick target and 4. 36 nb for thin the target.