Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions

XING Yong-Zhong; LIU Jian-Ye; GUO Wen-Jun

Chinese Physics C> 2004, Vol. 28> Issue(6) : 607-610

Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions

Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator,Lanzhou 730000,China2 Institute for the Theory of Modern Physics,Tianshui Normal University,Tianshui 741000,China3 Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China4 CCAST Word Lab.,Beijing 100080,China

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Abstract：
The liquid-gas phase transition in the heavy ion collisions and nuclear matter has been an important topic and got achievements, such as, based on the studies by H. Q. Song et al the critical temperature of liquid-gas phase transition enhances with increasing the mass of system and reduces as the increase of the neutron proton ratio of system. As we know that both the liquid-gas phase transition and the isospin fractionation occur in the spinodal instability region at the nuclear density below the normal nuclear density. In particular, these two dynamical processes lead to the separation of nuclear matter into the liquid phase and gas phase. In this case to compare their dynamical behaviors is interested. We investigate the dependence of isospin fractionation degree on the mass and neutron proton ratio of system by using the isospin dependent quantum molecular dynamics model. We found that the degree of isospin fractionation (N/Z)_n/(N/Z)_imf decreases with increasing the mass of the system. This is just similar to the enhance of the critical temperature of liquid-gas phase transition T c as the increase of system mass. Because the enhance of T c is not favorable for the liquid-gas transition taking place, which reduces the isospin fractionation process and leads to decrease of (N/Z)_n/(N/Z)_imf. However the degree of isospin fractionation enhances with increasing the neutron proton ratio of the system. It is just corresponding to the reduce of T_c of the liquid-gas phase transition as the increase of the isospin fractionation of the system. Because the reduce of T_c enhances the liquid-gas phase transition process and also prompts the isospin fractionation process leading the increase of the isospin fractionation degree. To sum up, there are very similar dynamical behaviors for the degree of isospin fractionation and the critical temperature of the liquid-gas phase transition. So dynamical properties of the liquid-gas phase transition can be measured and studied through the studies of isospin fractionation experimentally.

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[1]

. 　LI Bao-An. Phys. Rev. Lett . , 2000 , 85(20) :42212.　LI Bao-An , KO Che-Ming , REN Z Z et al . Phys. Rev. Lett . , 1997 ,78 :16443.　Colonna M, Di Toro M et al . Phys. Rev. , 1998 , C57 :1410 —1415 ;Di Toro M et al . Nucl . Phys. , 2001 , A681 :426C4.　Baran V , Colonna M, Di Toro Met al . Nucl . Phys. , 2002 , A703 :6035.　XU H et al . Phys. Rev. Lett . , 2000 , 85 : 716 ; Tsang M B et al .Phys. Rev. Lett . , 2001 , 86 :50236.　LIU Jian-Ye , GUO Wen-Jun , XING Zhong-Zhong. Nucl . Phys. ,2003 , A723 :483 —4957.　LI B A , Udo Schroder W. Isospin Physics in Heavy-Ion Collisions at Intermediate Energies ( book) , Nova Science Publishers , New York ,Inc , 20018.　Bertsch G F , Gupta S D. Phys. Rep. , 1988 , 160 :19919.　Aichelin J et al . Phys. Rev. Lett . , 1987 , 58 :192610.　Aichelin J et al . Phys. Rev. , 1988 , C37 :245111.　LIU Jian-Ye , GUO Wen-Jun , WANG Shun-Jin et al . Phys. Rev.Lett . , 2001 , 86 (6) :975 —978 ; YANG Yan-Fang , LIUJian-Ye , ZUOWei et al . Chin. Phys. Lett . , 2001 , 18(8) :104012.　SONG H Q et al . J . Phys. , 1990 , G16 :186113.　SONG H Q et al . Chin. Phys. Lett . , 1989 , 7 :11714.　Reinhard P Get al . Computational Nuclear Physics , Vol . 1 , Edited byK. Longanke et al . Springer-Verlag , Berlin : 1991 , 28 —50 ;Danielewicz. Nucl . Phys. , 2000 , A673 :37515.　LI B A , KO C M, Bauer W. Int . J . Mod. Phys. , 1998 , E7 :14716.　Klakow D , Welke G, Bauer W. Phys. Rev. , 1993 , C48 :198217.　Alkahzov Get al . Nucl . Phys. , 1977 , A280 :365

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[14]	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.
[15]	ZHAO Qiang , LIU JianYe , ZHANG FengShou , WANG ShunJin , ZUO Wei , CHEN LieWen . Isospin Effect in Multifragmentation Process of Heavy Ion Collisions at Intermediate Energy. Chinese Physics C, 2000, 24(11): 1024-1029.
[16]	Chen Liewen , Zhang Fengshou , Jin Genming . Isospin Effects on Balance Energy in HIC at Intermediate Energies. Chinese Physics C, 1999, 23(5): 469-474.
[17]	Chu Zili , Zheng Yuming . Simulation of Heavy-Ion Collision With Isospi-Separated RVUU Model. Chinese Physics C, 1998, 22(5): 429-433.
[18]	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.
[19]	Chen Liewen , Zhang Xiaodong , Ge Lingxiao . Isospin Effects on Pre-equilibrium NucleonEmission in Heavy Ion Collisions. Chinese Physics C, 1996, 20(12): 1091-1096.
[20]	Zhu Quanling , Ge Lingxiao , Zhang Xiaodong . Isospin Effects on Dynamics of Heavy Ion Collisions. Chinese Physics C, 1994, 18(9): 853-857.

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XING Yong-Zhong, LIU Jian-Ye and GUO Wen-Jun. Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions[J]. Chinese Physics C, 2004, 28(6): 607-610.

XING Yong-Zhong, LIU Jian-Ye and GUO Wen-Jun. Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions[J]. Chinese Physics C, 2004, 28(6): 607-610. shu

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Received: 2003-08-18
Revised: 1900-01-01

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通讯作者: 陈斌, bchen63@163.com

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沈阳化工大学材料科学与工程学院沈阳 110142

Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions

Corresponding author: XING Yong-Zhong,

Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator,Lanzhou 730000,China2 Institute for the Theory of Modern Physics,Tianshui Normal University,Tianshui 741000,China3 Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China4 CCAST Word Lab.,Beijing 100080,China

Received Date: 2003-08-18

Accepted Date: 1900-01-01

Available Online: 2004-06-05

Abstract: The liquid-gas phase transition in the heavy ion collisions and nuclear matter has been an important topic and got achievements, such as, based on the studies by H. Q. Song et al the critical temperature of liquid-gas phase transition enhances with increasing the mass of system and reduces as the increase of the neutron proton ratio of system. As we know that both the liquid-gas phase transition and the isospin fractionation occur in the spinodal instability region at the nuclear density below the normal nuclear density. In particular, these two dynamical processes lead to the separation of nuclear matter into the liquid phase and gas phase. In this case to compare their dynamical behaviors is interested. We investigate the dependence of isospin fractionation degree on the mass and neutron proton ratio of system by using the isospin dependent quantum molecular dynamics model. We found that the degree of isospin fractionation (N/Z)_n/(N/Z)_imf decreases with increasing the mass of the system. This is just similar to the enhance of the critical temperature of liquid-gas phase transition T c as the increase of system mass. Because the enhance of T c is not favorable for the liquid-gas transition taking place, which reduces the isospin fractionation process and leads to decrease of (N/Z)_n/(N/Z)_imf. However the degree of isospin fractionation enhances with increasing the neutron proton ratio of the system. It is just corresponding to the reduce of T_c of the liquid-gas phase transition as the increase of the isospin fractionation of the system. Because the reduce of T_c enhances the liquid-gas phase transition process and also prompts the isospin fractionation process leading the increase of the isospin fractionation degree. To sum up, there are very similar dynamical behaviors for the degree of isospin fractionation and the critical temperature of the liquid-gas phase transition. So dynamical properties of the liquid-gas phase transition can be measured and studied through the studies of isospin fractionation experimentally.

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Liquid-Gas Phase Transition and Isospin Fractionation in Intermediate Energy Heavy Ion Collisions

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