A Study of the Energy Limit for Measuring Fusion Cross Sections with the Active Target Technique

JI Liancheng; ZHANG Ningtao; LIN Weiping; TANG Xiaodong

doi:10.11804/NuclPhysRev.35.02.119

Reaction rates of fusion reactions among neutron-rich nuclei in the astrophysical environment are of great significance to understand the ignition of superbursts on neutron stars. Since beam intensity is rather low for radioactive ion beams, it is extremely difficult to operate a direct measurement for cross sections of such fusion reactions below the Coulomb barrier using thick target technique. In this case, a novel technique, active target technique, has been developed recently. To study the energy limit for measurement below Coulomb barrier, the kinematics of elastic scattering and fusion reaction in MUSIC and TPC are discussed with Geant4 simulation. Four identification methods are used and uncertainties of cross sections resulted from misjudgments are calculated. With E_cm=13.6 MeV, the uncertainties of cross sections for MUSIC and TPC are 0.5 mb and 2.9×10^-3 mb, respectively. The uncertainties for MUSIC become far beyond measurement when below coulomb barrier, while TPC remains to be a suitable detector for measuring fusion cross sections until E_cm=4.7 MeV.

A Study of the Energy Limit for Measuring Fusion Cross Sections with the Active Target Technique

1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;

2. Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China

Funds: National Key Research and Development Program of China (2016YFA0400501); National Natural Science Foundation of China (U1632142)

Received Date: 2018-04-13

Rev Recd Date: 2018-05-15

Publish Date: 2018-06-20

Key words:

Abstract: Reaction rates of fusion reactions among neutron-rich nuclei in the astrophysical environment are of great significance to understand the ignition of superbursts on neutron stars. Since beam intensity is rather low for radioactive ion beams, it is extremely difficult to operate a direct measurement for cross sections of such fusion reactions below the Coulomb barrier using thick target technique. In this case, a novel technique, active target technique, has been developed recently. To study the energy limit for measurement below Coulomb barrier, the kinematics of elastic scattering and fusion reaction in MUSIC and TPC are discussed with Geant4 simulation. Four identification methods are used and uncertainties of cross sections resulted from misjudgments are calculated. With E_cm=13.6 MeV, the uncertainties of cross sections for MUSIC and TPC are 0.5 mb and 2.9×10^-3 mb, respectively. The uncertainties for MUSIC become far beyond measurement when below coulomb barrier, while TPC remains to be a suitable detector for measuring fusion cross sections until E_cm=4.7 MeV.

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Reference (13)

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A Study of the Energy Limit for Measuring Fusion Cross Sections with the Active Target Technique

doi: 10.11804/NuclPhysRev.35.02.119

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