Study Of Reaction Cross Section In Low Energy For ～(14)N(～(16)O, α)～(26)Al With AMS

In early 1980s, with y radial sequence spectropmetry from the Milky Way, astronomers proposed that there exist 2~3M of 26Al(T1/2=7.2x105u) in the Milky Way, then deduced thatthese Al are produced and tossed to the astrospace from some stars in near age (the half life of 26Al is short comparatively astro-age). "From what stars are these 26Al produced?" become one of the important problems of the present astrophy research. Based on the fresh nuclear physics experiment data, the current available celestial body models (including nova and supernova) could not absolutely solve the problem on the source of 26Al. A theory arose, that SNIa is new approach through which 26Al could be synthesized. For example (N+O) heave ion fusion reaction. For study on (N+O) reaction producing 26Al, the AMS lab in CIAE put forward studying the (N+O) reaction cross section on Al. We use Accelerator Mass Spectropmetry(AMS) to measure the numbers of long life radioactive nuclide. The AMS system in CIAE have directly and sensitively measured 26Al. Based on the study of (N+O) reaction cross section by AMS, a new 26Al resource model is established. Furthermore, the AMS application study on heavy ion fusion in low energy can provide more data for many cosmic nuclide source.This paper mainly introduces the system of this experiment, including heavy ion fusion producing 26Al, preparation of AMS samples and measurement of minim nuclei 26Al with AMS. Feasibility of measuring fusion cross section in low energy with AMS is probed by discussing the better experiment conditions and methods, by which the AMS application is developed in nuclear physics, cosmography physics etc. This method is used the first time in this world by us.This paper consists of five chapters. The first chapter content is physics knowledge of experiment, basic principles of AMS and principles of AMS measure small reaction cross section.The second chapter introduces heavy ion reaction 14N (16O, a) 26Al by accelerator at Beijing HI-13 lane accelerator in CIAE and EN static lane accelerator in Heavy Ion Physics Institution of PKU. Electing and designing the reaction target, fixing by energy, voltage, charge of ion beam are important procedures of this experiment process. The reaction cross section by y radial sequence spectropmetry( o =1.410X100,1.027X10-1,4.726X10-3(b)for Ec.m.=12,10,8(MeV)) can compare with the result of literature.With some experiment results, the reaction 14N (16O, a) 26Al is proved to realize, and it produce target of AMS sample.The third chapter introduces the chemistry flow of the reaction target. 26Al of reaction target is distilled by carrier of pure 26Al, then 26Al sample of AMS is made out, at the same time, the reclaim efficiency directly influence measurement effect.The fourth chapter content is the measurement of 26Al with AMS. The theoretic conclusion and experiment are fixed on better conditions of AMS measurement experiment on Al, so enhance precision of measurement. The results of AMS experiment indicate that AMS can offerhigh precision measurement of 26Al(26Al/27Al=10-14), farther the feasibility of reaction 14N (16O, a) 26Al experiment is affirmed.The fifth chapter content is the summary and discussion and how to improve further experiment.