Research on the Measurement of Intermediate Mass Fragments Based on a Silicon Telescope System

Kun Yang; Xiangjun Liao

doi:10.63313/AJET.9024

Authors

Kun Yang Minzu Normal University of Xingyi, Xingyi 562400, China Author
Xiangjun Liao Minzu Normal University of Xingyi, Xingyi 562400, China Author

DOI:

https://doi.org/10.63313/AJET.9024

Keywords:

Intermediate Mass Fragments, heavy-ion collisions, silicon telescope, ΔE-E particle identification

Abstract

Intermediate Mass Fragments (IMFs) produced in heavy-ion collisions at Fermi energies are crucial observables for investigating reaction mechanisms, nuclear matter properties, and multifragmentation dynamics. Their production is closely related to the nuclear equation of state, liquid-gas phase transition, and the compression-epansion process of excited nuclear matter. Reliable measurements of IMF charge, mass, energy, and angular distributions are essential for understanding the thermodynamic evolution and dynamical behavior of nuclear systems under intermediate-energy collisions. In this study, a multi-layer silicon telescope system composed of four silicon detectors and a CsI(Tl) scintillator was employed to measure IMFs emitted from the Sn reaction. Positioned at relative to the beam direction, the telescope covers two angular ranges and provides adequate solid-angle coverage for fragments detection.

Clear ΔE-E correlation spectra were obtained, enabling isotopic identification from He (Z = 2) up to Ca (Z = 20). Up to 6-8 isotopic lines were resolved for each element, demonstrating excellent particle identification and energy resolution. After detector calibration and linearization, energy spectra and fragment yields were extracted. The experimental data exhibit characteristic multifragmentation features commonly observed in the Fermi-energy domain. The obtained IMF distributions provide meaningful constraints for nuclear reaction models and transport simulations.

This work demonstrates the capability of the Si-CsI telescope system for IMF measurements and provides a robust experimental foundation for future studies of reaction mechanisms, thermal properties of nuclear matter, and isotopic scaling behaviors in intermediate-energy heavy-ion collisions.

References

[1] Borderie, B., and Rivet, M. F. (2008). Nuclear multifragmentation and phase transition for hot nuclei. Progress in Particle and Nuclear Physics, 61(2), 551-601. https://doi.org/10.1016/j.ppnp.2008.01.003

[2] Chomaz, P., Colonna, M., and Randrup, J. (2004). Nuclear spinodal fragmentation. Physics Reports, 389(5-6), 263-440. https://doi.org/10.1016/j.physrep.2003.09.006

[3] Gross, D. H. E. (1990). Statistical decay of very hot nuclei-the production of large clusters. Reports on Progress in Physics, 53(5), 605. https://doi.org/10.1088/0034-4885/53/5/003

[4] Ogilvie, C. A., Adloff, J. C., Begemann-Blaich, M., Bouissou, P., Hubele, J., Imme, G., ... and Tucholski, A. (1991). Rise and fall of multifragment emission. Physical review letters, 67(10), 1214. https://doi.org/10.1103/PhysRevLett.67.1214

[5] Tsang, M. B., Friedman, W. A., Gelbke, C. K., Lynch, W. G., Verde, G., and Xu, H. S. (2001). Isotopic scaling in nuclear reactions. Physical Review Letters, 86(22), 5023. https://doi.org/10.1103/PhysRevLett.86.5023

[6] Shetty, D. V., Yennello, S. J., and Souliotis, G. A. (2007). Density dependence of the sym-metry energy and the nuclear equation of state: A dynamical and statistical model per-spective. Physical Review C, 76(2), 024606. https://doi.org/10.1103/PhysRevC.76.024606

[7] Ono, A., and Horiuchi, H. (2004). Antisymmetrized molecular dynamics for heavy ion col-lisions. Progress in Particle and Nuclear Physics, 53(2), 501-581. https://doi.org/10.1016/j.ppnp.2004.05.002

[8] Ono, A., Horiuchi, H., Maruyama, T., and Ohnishi, A. (1992). Antisymmetrized version of molecular dynamics with two-nucleon collisions and its application to heavy ion reactions. Progress of theoretical physics, 87(5), 1185-1206. https://doi.org/10.1143/ptp/87.5.1185

[9] Aichelin, J. (1991). “Quantum” molecular dynamics—a dynamical microscopic n-body approach to investigate fragment formation and the nuclear equation of state in heavy ion collisions. Physics Reports, 202(5-6), 233-360. https://doi.org/10.1016/0370-1573(91)90094-3

[10] Bertsch, G. F., and Gupta, S. D. (1988). A guide to microscopic models for intermediate en-ergy heavy ion collisions. Physics Reports, 160(4), 189-233. https://doi.org/10.1016/0370-1573(88)90170-6

[11] Li, B. A., Chen, L. W., and Ko, C. M. (2008). Recent progress and new challenges in isospin physics with heavy-ion reactions. Physics Reports, 464(4-6), 113-281. https://doi.org/10.1016/j.physrep.2008.04.005

[12] Pouthas, J. O. E. L., Borderie, B., Dayras, R., Plagnol, E., Rivet, M. F., Saint-Laurent, F., ... and Wittwer, G. (1995). INDRA, a 4π charged product detection array at GANIL. Nuclear In-struments and Methods in Physics Research Section A: Accelerators, Spectrometers, De-tectors and Associated Equipment, 357(2-3), 418-442. https://doi.org/10.1016/0168-9002(94)01543-0

[13] Pagano, A. (2012). Studies of Nuclear Reactions and Time Scale with the 4π Detector CHIMERA. Nuclear Physics News, 22(1), 25-30. https://doi.org/10.1080/10619127.2011.629922

[14] FAZIA Collaboration, Upadhyaya, S., Mazurek, K., Kozik, T., Gruyer, D., Casini, G., ... and Vig-ilante, M. (2024). Study of quasi-projectile properties at Fermi energies in 48 Ca projectile systems. The European Physical Journal A, 60(7), 157. https://doi.org/10.1140/epja/s10050-024-01369-5

[15] Lopez, O., Pârlog, M., Borderie, B., Rivet, M. F., Lehaut, G., Tabacaru, G., ... and INDRA col-laboration. (2018). Improving isotopic identification with INDRA Silicon–CsI (Tl) tele-scopes. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 884, 140-149. https://doi.org/10.1016/j.nima.2017.12.041

[16] Hudan, S., Chbihi, A., Frankland, J. D., Mignon, A., Wieleczko, J. P., Auger, G., ... and INDRA Collaboration. (2003). Characteristics of the fragments produced in central collisions of 129 Xe+ nat Sn from 32A to 50 A MeV. Physical Review C, 67(6), 064613. https://doi.org/10.1103/PhysRevC.67.064613