A CsI hodoscope on CSHINE for Bremsstrahlung γ-rays in Heavy Ion Reactions

Abstract

Bremsstrahlung $\gamma$ production in heavy ion reactions at Fermi energies carries important physical information including the nuclear symmetry energy at supra-saturation densities. In order to detect the high energy Bremsstrahlung $\gamma$ rays, a hodoscope consisting of 15 CsI(Tl) crystal read out by photo multiplier tubes has been built, tested and operated in experiment. The resolution, efficiency and linear response of the units to $\gamma$ rays have been studied using radioactive source and $(\mathrm{p},\gamma )$ reactions. The inherent energy resolution of $1.6\%+2\%/E_{\gamma }^{1/2}$ is obtained. Reconstruction method has been established through Geant 4 simulations, reproducing the experimental results where comparison can be made. Using the reconstruction method developed, the whole efficiency of the hodoscope is about $2.6\times 10^{-4}$ against the $4\pi$ emissions at the target position, exhibiting insignificant dependence on the energy of incident $\gamma$ rays above 20 MeV. The hodoscope is operated in the experiment of ${}^{86}$Kr + ${}^{124}$Sn at 25 MeV/u, and a full $\gamma$ energy spectrum up to 80 MeV has been obtained.

9 pages, 19 figures

References in corpus (6)

• Results of the ASY-EOS experiment at GSI: The symmetry energy at suprasaturation density
• Neutron and Proton Transverse Emission Ratio Measurements and the Density Dependence of the Asymmetry Term of the Nuclear Equation of State
• The Emission Order of Hydrogen Isotopes via Correlation Functions in 30 MeV/u Ar+Au Reactions
• Probing high-density nuclear symmetry energy with ${\Xi }^{-}/{\Xi }^0$ ratio in heavy-ion collisions at $\sqrt{s_{NN}}\sim 3$ GeV
• Neutron-proton bremsstrahlung from intermediate energy heavy-ion reactions as a probe of the nuclear symmetry energy?
• ${}^3$H/${}^3$He ratio as a probe of the nuclear symmetry energy at sub-saturation densities

Cited by in corpus (6)

• Reconstruction of Bremsstrahlung $\gamma$-rays Spectrum in Heavy Ion Reactions with Richardson-Lucy Algorithm
• Extract neutron-neutron interaction strength and spatial-temporal dynamics of neutron emission from two-particle correlation function
• Measurement of the high energy $\gamma$-rays from heavy ion reactions using Čerenkov detector
• Precise Measurement of Short-Range Correlations in Nuclei from Bremsstrahlung Gamma Ray Emission in Low-Energy Heavy-Ion Collisions
• Linear Response of CsI(Tl) Crystal to Energetic Photons below 20 MeV
• Experimental Study of Bremsstrahlung Gamma Ray Emission and Short-Range Correlations in ${}^{124}$Sn+${}^{124}$Sn Collisions at 25 MeV/u