XU Junhuai;XIAO Zhigang;

• 1:Department of Physics
• 2:Tsinghua University

Abstract：

Nuclei are not bags of static balls.Most protons and neutrons move under the overall nuclear environment,but a small fraction can form fleeting close-range partners and carry unusually large momenta.These short-range correlations cannot be photographed directly.Instead,they leave statistical clues in the high-energy gamma-ray spectrum emitted at the earliest stage of a heavy-ion collision:faster neutron-proton encounters are more likely to produce energetic gamma rays,hardening the spectral tail.A recent ~(124)Sn+~(124)Sn experiment at 25 MeV per nucleon used this idea,together with transport-model comparisons,detector calibration,and background checks,to infer that about 20% of nucleons in ~(124)Sn belong to short-rangecorrelation-related high-momentum components.The result provides a complementary gamma-ray route for studying short-distance motion inside nuclei.

Key Words： short-range correlation;high-momentum tail;bremsstrahlung gamma ray;heavy-ion collision

Abstract:

Keywords:

Foundation: 国家自然科学基金项目（12335008）

Authors: XU Junhuai;XIAO Zhigang;

DOI: 10.27024/j.wlygc.2026.06.29.is

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