Paper

Extract neutron-neutron interaction strength and spatial-temporal dynamics of neutron emission from two-particle correlation function

Hao, Yibo, Ma, Peng, Wang, Kang, Yang, Yanyun, Guo, Dong, Xiao, Sheng, Guo, Yang, Zhang, Haojie, Wang, Yijie, Ma, Junbing, Wang, Zengxiang, Duan, Limin, Xianglun Wei, Si, Dawei, Yang, Yuansheng, Xu, Shiwei, Zhang, Boyuan, Tianren Zhuo, Qin, Yuhao, Xiao, Zhigang, Xu, Junhuai, Xiaobao Wei, Ma, Chunwang, Qin, Zhi, Bai, Zhen, Yang, Herun, Duan, Fangfang, Tian, Baiting

2025

Overview

The neutron-neutron (\\(nn\\)) correlation function has been measured in 25 MeV/u \\(^124\\)Sn+\\(^124\\)Sn reactions. Using the Lednický-Lyuboshitz approach, the \\(nn\\) scattering length and effective range (\\(f_0^nn\\), \\(d_0^nn\\)), as well as the reduced space-time size \\(R^(0)\\) of the neutron emission source are simultaneously extracted as (\\(18.9^+1.3_-1.2\\) fm, \\(1.9^+1.3_-1.0\\) fm) and \\(4.12 0.12\\) fm, respectively. The measured \\(nn\\) scattering length is consistent with the results obtained in the low-energy scattering \\(^2 H(^-,)2n\\), indicating heavy-ion collisions can serve as an effective approach for measuring \\(nn\\) interactions and further investigating the charge symmetry breaking of nuclear force. The space-time size extracted from momentum-gated correlation functions exhibits clear dependence on the pair momentum, with \\(R^(0)=2.8 0.1 \\) fm and \\(4.9 0.2\\) fm being determined for the high and low momentum neutrons, respectively.

• Publisher: Cornell University Library, arXiv.org
• Subject: Broken symmetry / Correlation / Heavy ions / Ionic collisions / Momentum / Neutron emission / Scattering