Preliminary results of the study of gamma-ray transitions in 11C and 11B nuclei in 9Be(3He,nγ)11C and 9Be(3He,pγ)11B reactions

Sep 22, 2021, 6:05 PM
1h 55m
Poster report Section 2. Experimental and theoretical studies of nuclear reactions. Poster session (Experimental and theoretical studies of nuclear reactions)

Speaker

Margarita Iliasova (Ioffe Institute)

Description

Excitation functions of gamma-transition in nuclei produced in reactions involving the 3He and 9Be ions are required to reconstruct distributions of fast 3He ions in thermonuclear plasma using gamma-ray spectrometry methods [1]. The distribution of fast ions can be obtained in two following ways: analyzing the gamma-line intensities measured by a gamma-spectrometer and analyzing the shape of the gamma-line broadened by the Doppler effect. The latter method also requires precise semiconductor spectrometers to be used in the measurements. The 3He minority ions are applied to the so-called three-ion ion-cyclotron radiofrequency (ICRF) scenario of tokamak plasma heating [2]. 3He ions accelerated to the MeV-energy range were observed in JET plasma [3]. The obtained data presented in this work will be applied for the analysis of the plasma heating regimes at JET and future facilities such as ITER.
Excitation functions of gamma-transition in 11C и 11B nuclei produced in reactions involving the 3He and 9Be ions were measured on the Cyclotron of Ioffe Institute in the energy range from 1.5 to 6 MeV. A target consisted of beryllium, deposited on a 0.5-mm-thick tantalum substrate, was used in the measurements. The thickness of beryllium is 212 μg/cm2. Gamma radiation was measured by two HPGe spectrometers with a relative efficiency of 49% and 56%. In the first measurements, the line shapes of 6.9-MeV gamma-transition from the 9Be(3He,nγ)11C reaction and 8.92-MeV transition from the 9Be(3He,pγ)11B reaction were obtained at the energy of 3He of 2.57 MeV [4]. In the present work, angular distributions of 2.0-, 4.32- and 6.9-MeV gamma-transitions from the 9Be(3He,nγ)11C reaction and 2.12-, 7.29- and 8.92-MeV transitions from the 9Be(3He,pγ)11B reaction were measured. Furthermore, based on the 7.29- and 8.92-MeV gamma-line shape analysis, the angular distribution of the proton emission upon the population of the corresponding excitation levels of the 11B nucleus was obtained, as well as the angular distribution of the neutron emission upon the population of the 6.9-MeV level of the 11C nucleus. In this work, the preliminary results of measurements of partial cross-sections and angular distributions of gamma quanta, protons and neutrons are presented at different energies of the 3He beam.

  1. V. G. Kiptily, F. E. Cecil, and S. S. Medley, Plasma Phys. Control. Fusion 48 R59 (2006)
  2. Ye. O. Kazakov et al., Nat. Phys. 13 973–8 (2017)
  3. V.G. Kiptily et al., Nucl. Fusion 50 084001(2010)
  4. M.V. Iliasova et al., Tech. Phys. Lett. 47 2 103–106 (2021)

Primary authors

Margarita Iliasova (Ioffe Institute) Dr Alexander Shevelev (Ioffe Institute) Mr Evgeny Khilkevitch (Ioffe Institute) Dr Victor Naidenov (Ioffe Institute) Dr Mikhail Kudoyarov (Ioffe Institute) Dr Dmitry Doinikov (Ioffe Institute) Mr Igor Polunovsky (Ioffe Institute)

Presentation materials