Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy

ZHAO Qiang; LIU JianYe; ZHANG FengShou; WANG ShunJin; ZUO Wei; CHEN LieWen

Chinese Physics C> 2000, Vol. 24> Issue(11) : 1024-1029

Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy

Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, China2 Institute of Modern Physics, The Chiness Academy of Sciences, Lanzhou 730000, China3 Institute of Modern Physics, South West Jiaotong University, Chengdu 610031, China

Abstract
HTML
Reference
Related

PDF

Abstract：
From the simulation of intermediate energy heavy ion collisions by using the isospin dependent quantum molecular dynamics (IQMD), we have investigated the isospin effects on the multifragmentation process in intermediate energy heavy ion collisions: reverse reactions 120Xe + 40Ca, 120Cd+ 40Ar, 76Kr + 40Ca and 76Zn + 40Ar. To describe isospin effects appropriately, QMD was modified properly. The density dependent mean field contains correct isospin term including symmetry energy and Coulomb potential. The in-medium n-n cross section is different for neuron-neutron (proton-proton) and neutron-proton collisions. And finally Pauli blocking was counted by distinguishing neutrons and protons. In addition, the initial condition of the ground state of two colliding nuclei also contains isospin information. The calculated results show a prominent isospin effects for the multifragmentation process among the colliding systems with different neutron or proton excess. The correlation between Nimf and Nc for neutron-deficient systems are always larger than those for neutron-rich systems in intermediate energy region for all of colliding systems studied here, and the mechanism causing the above isospin effects is mainly due to the fact that the mean n-n cross section for the neutron-rich system is smaller than that of neutron-deficient system. Thus one can combine experimental studies and theoretical simulations to investigate the isospin effect of multi fragmentation Process and to extract the information on isospin dependence of in-medium n-n cross section from the correlation between Nimf and Nc.

References

[1]

LI BaoAn, Ko CheMing et al. Inter. Jour. Mod. Phys., 1998, E: 147–229 2 Colonna M, Ditoro M et al. Phys. Rev., 1998, C57: 1410 3 CHEN LieWei, ZHANG FengShow et al. Phys. Rev., 1998, C58:2283 4 LI BaoAn, Ko CheMing et al. Phys. Rev. Lett., 1997, 78: 1644 5 LIU JianYe, GE YuCheng, YANG FuZhong. Z. Phys., 1993, A345: 187 6 LIU JianYe, ZHANG ShaoGuang. Z. Phys., 1994, A354:31 7 LIU Hang, LIU JianYe. Z. Phys., 1996, A354:311 8 Aichelin J, Peilert G et al. Phys. Rev., 1988, C37:2451 9 Peilert G, H Stocher et al. Phys. Rev., 1989, C39:1402 10 Klakor D, Welke G, Baur W. Phys. Rev., 1993, C48:1982. 11 Alkahzov G et al. Nucl. Phys. 1977, A280:365

[1]	LIU Jian-Ye , GUO Wen-Jun , Xing Yong-Zhong , LI Xi-Guo . Isospin Effect of Momentum Dependent Interaction in Heavy Ion Collisions. Chinese Physics C, 2005, 29(5): 456-460.
[2]	XING Yong-Zhong , LIU Jian-Ye , GUO Wen-Jun . Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2004, 28(6): 607-610.
[3]	XING Yong-Zhong , LIU Jian-Ye , GUO Wen-Jun . Isospin Effects in the Isospin Fractionation Process in Intermediate Energy HeavyIon Collisions. Chinese Physics C, 2004, 28(4): 403-407.
[4]	LI Zhu-Xia , ZHANG Ying-Xun , LI Qing-Feng , ZHAO Kai , WU Xi-Zhen . Isospin Effect in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2004, 28(12): 1343-1348.
[5]	GUO Wen-Jun , LIU Jian-Ye , XING Yong-Zhong , ZUO Wei , LI Xi-Guo . Isospin Fractionation Process in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2003, 27(10): 897-900.
[6]	HU Rong-Jiang , WU He-Yu , JIN Gen-Ming , ZHU Yong-Tai , LI Song-Lin , XIAO Zhi-Gang , WANG Hong-Wei , DUAN Li-Min , LI Zu-Yu , YIN Xu , WANG Su-Fang , ZHANG Bao-Guo , WEI Zhi-Yo , , , . Isospin Effect of Charged Particle Multiplicity in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2003, 27(11): 990-994.
[7]	XING Yong-Zhong , LIU Jian-Ye , GUO Wen-Jun , ZUO Wei , LI Xi-Guo . Role of Momentum Dependent Interaction on the Isospin Effects of Fragmentations and Dissipations at Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2002, 26(S1): 63-72.
[8]	GUO Wen-Jun , LIU Jian-Ye , ZUO Wei , XING Yong-Zhong , LI Xi-Guo , LI Zeng-Hua . Isospin Effect of Neutron (Proton) Emission Number in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2002, 26(12): 1264-1270.
[9]	ZHAO Qiang , GUO Wen-Jun , LIU Jian-Ye , ZUO Wei , WANG Shun-Jin . Isospin Dependence of Preequilibrium Nucleon Emission in Intermediate Energy Heavy Ion Collision. Chinese Physics C, 2001, 25(3): 244-250.
[10]	CHEN Bo , LIU JianYe , ZHANG FengShou , CHEN LieWen , ZHAO Qiang , ZUO Wei . Isospin Effects on Multifragmentation of Light Mass System. Chinese Physics C, 2000, 24(3): 244-249.
[11]	ZHAO Qiang , CHEN Bo , LIU JianYe , ZHANG FengShou , WANG ShunJin , CHEN LieWen , ZUO Wei . Probable Observable of Isospin Dependent Nucleon-Nucleon Cross Section in Inter Mediate Energy Heavy Ion Collisions. Chinese Physics C, 2000, 24(5): 426-430.
[12]	CHEN Bo , ZHAO Qiang , LIU JianYe , ZHANG FengShou , WANG ShunJin , CHEN LieWen , ZUO Wei . A Sensitive Probe for Isospin-Dependent Nucleon-Nucleon Cross Section in Intermediate Energy Heavy Ion Collision. Chinese Physics C, 2000, 24(4): 326-330.
[13]	FANG DeQing , SHEN WenQing , FENG Jun , CAI XiangZhou , SU QianMin , MA YuGang . Isospin Effect of Fragmentation Reaction and Its Disappearance in Intermediate Energy Heavy Ion Collisions. Chinese Physics C, 2000, 24(10): 949-954.
[14]	Chen Liewen , Zhang Fengshou , Jin Genming . Isospin Effects on Balance Energy in HIC at Intermediate Energies. Chinese Physics C, 1999, 23(5): 469-474.
[15]	Chen Liewen , Zhang Fengshou , Zeng Xianghua , Jin Genming . Isospin Effects on Collective Flow in HIC at Intermediate Energies. Chinese Physics C, 1998, 22(11): 1035-1041.
[16]	Chen Liewen , Zhang Xiaodong , Ge Lingxiao . Isospin Effects on Pre-equilibrium NucleonEmission in Heavy Ion Collisions. Chinese Physics C, 1996, 20(12): 1091-1096.
[17]	Liu Hang , Liu Jianye , Zhang Shaoguang , Li Junqing . Multifragmentation Process in HIC Simulated by Modified Quantum Molecular Dynamics. Chinese Physics C, 1995, 19(11): 1040-1046.
[18]	Zhang Shaoguang , Liu Jianye . Multifragmentation in Heavy Ion Collisions. Chinese Physics C, 1994, 18(S1): 64-70.
[19]	Zhu Quanling , Ge Lingxiao , Zhang Xiaodong . Isospin Effects on Dynamics of Heavy Ion Collisions. Chinese Physics C, 1994, 18(9): 853-857.
[20]	GE Ling-Xiao , ZENG Xiang-Hua , LIU Jian-Ye , ZENG Bao-Sheng . THE EFFECT OF COMPRESSION AND THERMAL EXCITATION FOR FRAGMENTATION DYNAMICS PROCESS OF HIC. Chinese Physics C, 1990, 14(3): 278-281.

Access

Get Citation

ZHAO Qiang, LIU JianYe, ZHANG FengShou, WANG ShunJin, ZUO Wei and CHEN LieWen. Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy[J]. Chinese Physics C, 2000, 24(11): 1024-1029.

RIS(for EndNote,Reference Manager,ProCite)

BibTex

Txt

Milestone

Received: 1999-09-07
Revised: 1900-01-01

Article Metric

Article Views(3836)
PDF Downloads(678)
Cited by(0)

Policy on re-use

To reuse of subscription content published by CPC, the users need to request permission from CPC, unless the content was published under an Open Access license which automatically permits that type of reuse.

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy

Corresponding author: ZHAO Qiang,

Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, China2 Institute of Modern Physics, The Chiness Academy of Sciences, Lanzhou 730000, China3 Institute of Modern Physics, South West Jiaotong University, Chengdu 610031, China

Received Date: 1999-09-07

Accepted Date: 1900-01-01

Available Online: 2000-11-05

Abstract: From the simulation of intermediate energy heavy ion collisions by using the isospin dependent quantum molecular dynamics (IQMD), we have investigated the isospin effects on the multifragmentation process in intermediate energy heavy ion collisions: reverse reactions 120Xe + 40Ca, 120Cd+ 40Ar, 76Kr + 40Ca and 76Zn + 40Ar. To describe isospin effects appropriately, QMD was modified properly. The density dependent mean field contains correct isospin term including symmetry energy and Coulomb potential. The in-medium n-n cross section is different for neuron-neutron (proton-proton) and neutron-proton collisions. And finally Pauli blocking was counted by distinguishing neutrons and protons. In addition, the initial condition of the ground state of two colliding nuclei also contains isospin information. The calculated results show a prominent isospin effects for the multifragmentation process among the colliding systems with different neutron or proton excess. The correlation between Nimf and Nc for neutron-deficient systems are always larger than those for neutron-rich systems in intermediate energy region for all of colliding systems studied here, and the mechanism causing the above isospin effects is mainly due to the fact that the mean n-n cross section for the neutron-rich system is smaller than that of neutron-deficient system. Thus one can combine experimental studies and theoretical simulations to investigate the isospin effect of multi fragmentation Process and to extract the information on isospin dependence of in-medium n-n cross section from the correlation between Nimf and Nc.

HTML

Reference (1)

Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy

Abstract：

References

Access

Article Metrics

Metrics

通讯作者: 陈斌, bchen63@163.com

Email This Article