Thermal Bremsstrahlung photons probing the nuclear caloric curve

Abstract

Hard-photon (E${}_{\gamma }>$ 30 MeV) emission from second-chance nucleon-nucleon Bremsstrahlung collisions in intermediate energy heavy-ion reactions is studied employing a realistic thermal model. Photon spectra and yields measured in several nucleus-nucleus reactions are consistent with an emission from hot nuclear systems with temperatures $T\approx$ 4 - 7 MeV. The corresponding caloric curve in the region of excitation energies ${\epsilon }^{\star }\approx$ 3{\it A} - 8{\it A} MeV shows lower values of $T$ than those expected for a Fermi fluid.

arXiv comment13 pages, 3 figures. To appear in Physics Letters B

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Cited by in corpus (8)

• Nuclear multifragmentation and phase transition for hot nuclei
• Limiting temperatures and the Equation of State of Nuclear Matter
• The interplay of short-range correlations and nuclear symmetry energy in hard photon productions from heavy-ion reactions at Fermi energies
• Constraining nucleon high momentum in nuclei
• Neutron-proton bremsstrahlung from intermediate energy heavy-ion reactions as a probe of the nuclear symmetry energy?
• Thermal and transport properties in central heavy-ion reactions around a few hundred MeV/nucleon
• A direct probe of the in-medium pn scattering cross section
• Direct photon emission and influence of dynamical wave packets in an extended quantum molecular dynamics model