Large amplification of the isospin-dependence of proton emitting source size in nuclear collisions induced by radioactive ion beams: A signal of n-p correlation
Year: 2026
Type: preprint
Abstract: We report proton-proton correlation function measurements in central $^{132}$Sn+$^{124}$Sn and $^{108}$Sn+$^{112}$Sn collisions at 270 MeV/nucleon. The proton emitting source sizes are extracted for the systems by using femtoscopic imaging technique. The fast dynamic core radius for the neutron-rich system is found to be $2.22 \pm 0.13\ \text{(stat.)} \pm 0.07\ \text{(syst.)}$ fm, which is approximately 24\% larger than that for the neutron-deficient system, $1.74 \pm 0.08\ \text{(stat.)} \pm 0.05\ \text{(syst.)}$ fm. This difference is an order of magnitude larger than the $\sim$3\% difference in the ground-state charge radii of the projectile nuclei. Transport model simulations based on mean-field dynamics cannot reproduce this amplification. The observation reveals a beyond-mean-field mechanism associated to short-range neutron-proton correlations, which dynamically enhance the proton emitting source in the neutron-rich environment. Our results demonstrate that heavy-ion collisions induced by radioactive beam, combined with femtoscopic precision, provide a new hadronic probe of short-range correlation, and that careful treatment of the beyond-mean-field interactions are required in modeling such processes.
Source: arXiv (Cornell University)
Authors: Wang, Y. J., Tam, C. K., Xiao, Z. G., Lynch, W. G., Tsang, C. Y., Barney, J., Jhang, G., Estee, J., Tsang, M. B., Wang, R. S., Kaneko, M., Lee, J. W., Park, J., Chajęcki, Z., Verde, G., Isobe, T., Kurata-Nishimura, M., Murakami, T., Ahn, D. S., Atar, L., Aumann, T., Baba, H., Boretzky, K., Brzychczyk, J., Cerizza, G., Chiga, N., Fukuda, N., Gasparic, I., Hong, B., Horvat, A., Ieki, K., Inabe, N., Kim, Y. J., Kobayashi, T., Kondo, Y., Lasko, P., Lee, H. S., Leifels, Y., Łukasik, J., Manfredi, J., McIntosh, A. B., Morfouace, P., Nakamura, T., Nakatsuka, N., Nishimura, S., Otsu, H., Pawłowski, P., Pelczar, K., Rossi, D., Sakurai, H., Santamaria, C., Sato, H., Scheit, H., Shane, R., Shimizu, Y., Simon, H., Snoch, A., Sochocka, A., Sumikama, T., Suzuki, H., Suzuki, D., Takeda, H., Tangwancharoen, S., Toernqvist, H., Togano, Y., Yennello, S. J., Zhang, Y.
Institutions: Western Michigan University, National Superconducting Cyclotron Laboratory, Michigan State University, Soochow University, Kyoto University, RIKEN Nishina Center, Korea University, GSI Helmholtz Centre for Heavy Ion Research, Technische Universität Darmstadt, Jagiellonian University, Rikkyo University, Institute for Basic Science, Tohoku University, Tokyo Institute of Technology, Institute of Nuclear Physics, Polish Academy of Sciences, Texas A&M University, National Institute for Subatomic Physics, Center of Excellence in Theoretical and Computational Science, King Mongkut's University of Technology Thonburi, Nanjing Normal University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, U.S. Department of Energy, National Research Foundation, Ministry of Education, Culture, Sports, Science and Technology, National Research Foundation of Korea, Tsinghua University, Hrvatska Zaklada za Znanost, Helmholtz International Center for FAIR, Japan Society for the Promotion of Science, RIKEN
Awards: G1883778784, G2227393196, G222768804, G2436857590, Cluster correlations in nuclear reactions and nuclear matter studied with transport models, Operation of the NSCL as a National User Facilty & Research Program, Comprehensive understanding of heavy-ion collision dynamics, pion production and Delta resonance in medium, NEW AWARD - "CYCLOTRON BASED NUCLEAR SCIENCE" PI - JOSEPH B.NATOWITZ, CONSTRAINING THE EQUATION OF STATE OF DENSE NEUTRON-RICH MATTER, G3534744629, G3888850926, Diversity of nuclear matter properties in heavy-ion collisions and Equation of State of asymmetric nuclear matter, TEXAS A&M UNIVERSITY CYCLOTRON INSTITUTE RESEARCH PLAN, G5548152103, G5965505636, G7476386635, G8195599115, G8784777311, ASYMMETRIC NUCLEAR MATTER UNDER EXTREME CONDITIONS
OpenAlex ID: W7157683734