Effect of Proximity Force on Potential Barrier in Fusion Reaction

CHEN Bao-Qiu; MA Zhong-Yu

Chinese Physics C> 2004, Vol. 28> Issue(10) : 1079-1082

Effect of Proximity Force on Potential Barrier in Fusion Reaction

CHEN Bao-Qiu ^, ,
MA Zhong-Yu

Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000,China2 China Institute of Atomic Energy,Beijing 102413,China3 Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100080,China

Abstract
HTML
Reference
Related

PDF

Abstract：
The macroscopic deformed potential energies for fusion reactions are determined within a generalized liquid drop model (GLDM) which includes the volume—,surface,and Coulomb energies,the proximity effects,the mass asymmetry,and an accurate nuclear radius. In ordinary fission studies,it is assumed that the surface and Coulomb energies control the hight and width of the barrier. The surface energy E_S takes into account only the effect of the surface tension force and does not include the contribution of the attractive nuclear forces between surfaces in regard to the neck or the gap between the nascent fragments. The nuclear proximity energy is adopted to take into account these additional surface effects in general liquid drop model. At the contact point,the proximity energy reaches maximum while it decreases both sides till to zero. The proximity energy decreases the barrier height by several MeV and moves the position of the barrier top forward,which corresponds to two separated fragments in unstable equilibrium by the balance between the attractive nuclear proximity force and the repulsive Coulomb force in the GDLM. It turns out that a wide macroscopic potential pocket in fusion process is formed due to proximity energy and appears at large deformation. This behavior does not appear at the barrier for the fusion reaction of light nucleus nucleus collision.

References

[1]

. Rutz K, Bender B, Buervenich T et al. Phys. Rev., 1997, C56: 2382. Patra S K, WU C L, Gupta R K. Nucl. Phys., 1999, A651: 117; Sil T,Patra S K, Sharma B K et al. nucl-th/03100103. Patra S K, Greiner W, Gupta R K. J. Phys., 2000, G26: L654. REN Z Z, Toki H. Nucl. Phys., 2001, A689: 6915. Gupta R K, Kumar S, Kumar R et al. J. Phys., 2002, G28: 28756. Oganessian Y T et al. Phys. Rev. Lett., 1999, 83: 31547. Oganessian Y T et al. Phys. Rev., 2000, C62: 041604( R)8. Hofmann S, Muenzenberg G. Rev. Mod. Phys., 2000, 72: 733; Arm-bruster P. E. Phys. J., 2000, A7: 79. Adamian G G et al. Nucl. Phys., 1998, A633: 409; Adamian G G etal. Nucl. Phys., 2000, A678: 2410. Denisov V, Yu Hofmann S. Phys. Rev., 2000, C61: 03460611. Smolanczuk R. Phys. Rev., 1999, C59: 2634; Phys. Rev., 2001,C63: 04460712. Royer G, Remaud B. Nucl. Phys., 1985, A444: 477; Royer G. J.Phys., 2000, G26: 114913. Sahu S, Agarwalla S K, Shastry C S. Nucl. Phys., 2003, A713: 4514. Feldmeier H. 12th Summer School on Nuclear Physics. Poland: Mikolajki, 197915. Royer G, Gherghesu R A. Nucl. Phys., 2002, A699: 479

[1]	DING Bin-Gang , ZHANG Da-Li , LU Ding-Hui . A study of the pairing strength in the rare-earth nuclei. Chinese Physics C, 2006, 30(7): 616-619.
[2]	TIAN Jun-Long , WU Xi-Zhen , LI Zhu-Xia . Study on Dynamic Fusion Barrier in Heavy-Ion Fusion Reactions. Chinese Physics C, 2006, 30(5): 428-434.
[3]	FENG Zhao-Qing , JIN Gen-Ming , ZHANG Feng-Shou , FU Fen , HUANG Xi . Dynamical Study on Fusion Mechanism near Coulomb Barrier. Chinese Physics C, 2005, 29(12): 1157-1161.
[4]	FENG Zhao-Qing , ZHANG Feng-Shou , LI Wen-Fei , JIN Gen-Ming . Nuclear Fusion near Coulomb Barrier. Chinese Physics C, 2005, 29(1): 41-45.
[5]	LIU Ling , LU Kun , BAO Jing-Dong . Dynamic Back-Streaming Effects around Fusion and Fission Barriers of Heavy Nuclei. Chinese Physics C, 2004, 28(8): 854-858.
[6]	TIAN Jun-Long , WU Xi-Zhen , LI Zhu-Xia , WANG Ning , LIU Fu-Hu . Study on Fusion Potential Barrier in Heavy Ion Reactions Based on the Dynamical Model. Chinese Physics C, 2004, 28(7): 725-732.
[7]	WU Yue-Wei , LIU Zu-Hua , LIN Cheng-Jian , ZHANG Huan-Qiao , RUAN Ming , YANG Feng , Ll Zhi-Chang , LIU Jian-Cheng . Measurement of Near-Barrier Fusion Excitation Function of ⁶Li+²⁰⁸Pb. Chinese Physics C, 2003, 27(5): 399-401.
[8]	Zhang Huanqiao , Yang Feng , Lin Chengjian , Liu Zuhua , Hu Yueming . Barrier Distributions for the Quasi-elastic andElastic Scattering of ¹⁶O+¹⁵²Sm,¹⁸⁴W. Chinese Physics C, 1998, 22(9): 769-779.
[9]	Tan Jilian , Zhang Jinxia , Jin Genming , Zhang Huanqiao , Qian Xing , Liu Zuhua , Xu Jincheng . Bi—dimension Position Sensitive Detector Used in the Study of Fusion Fission of Heavy Ions at the Sub—Coulomb Barrier Energy Region. Chinese Physics C, 1997, 21(1): 8-14.
[10]	Qian Xing , Jiang Dongxing , Lin Junsong , Liu Daming , Li Ze . Cross Sections of Evaporation Residues of ¹²C＋⁹³Nb in the Vicinity of the Coulomb Barrier. Chinese Physics C, 1995, 19(7): 603-611.
[11]	Dai Guangxi . Deformation Potentials in Symmetric Multi-Fold Fission and Their Temperature-Dependence. Chinese Physics C, 1995, 19(5): 447-454.
[12]	Liu Zuhua , Zhang Huanqiao , Xu Jincheng , Qian Xing , Qiao Yu , Lin Chengjian , Xu Kan . Anomaly Observed in Subbarrier Fusion-Fission Reactions. Chinese Physics C, 1995, 19(7): 585-590.
[13]	Liu Zuhua , Xu Jincheng , Zhang Huanqiao , Qian Xing , Qiao Yu , Lin Chengjian , Xu Kan . Subbarrier Complete Fusion-Fission Reactions of ¹⁶)O+²³²Th. Chinese Physics C, 1994, 18(6): 489-495.
[14]	DONG Yu-Bing , YU You-Wen . The Effects of Different Kinds of Confinements and Configuration Space on N、Δ Spectra. Chinese Physics C, 1993, 17(7): 651-657.
[15]	SHENG Hong , HE Guo-Zhu . An Interpretation of Sub-Barrier Fusion Reaction Based on α Transfer Mechanism. Chinese Physics C, 1993, 17(2): 161-165.
[16]	ZHANG Huan-Qiao , LIU Zu-Hua , XU Jin-Cheng , RUAN Ming , QIAN Xing , XU Kan , LV Jun . Fission-Fragment Angular Distributions for the ¹⁶O+²³⁸U Near-and Sub-Barrier Fusion-Fission Reaction. Chinese Physics C, 1992, 16(9): 826-831.
[17]	DAI Guang-Xi , , , , , , , , , , , . THE SHELL EFFECT IN SEQUENTIAL FISSION INDUCED BY ²³⁸U WITH ENERGY JUST ABOVE COULOMB BARRIER. Chinese Physics C, 1985, 9(4): 454-460.
[18]	ZHONG Yun-Xiao , CHEN Jun-Zhen . THE RATE OF ESCAPE OF BROWNIAN PARTICLE OVER DOUBLY PEAKED POTENTIAL BARRIERS. Chinese Physics C, 1985, 9(3): 356-361.
[19]	Xu SHU-WEI . A COMPLEMENTARY ANALYSIS OF THE EXPERIMENTAL DATA FOR REACTION ¹²C+²⁰⁹Bi AT THE INCIDENT ENERGIES SLIGHTLY ABOVE THE COULOMB BARRIER. Chinese Physics C, 1981, 5(4): 518-520.
[20]	XU SHU-WEI , RAN QI-HUI , MA HONG-FAN . A SEMI-CLASSICAL ANALYSIS ON THE REACTION ¹²C+²⁰⁹Bi AT BOMBARDING ENERGIES SLIGHTLY ABOVE THE COULOMB BARRIER. Chinese Physics C, 1978, 2(6): 534-543.

Access

Get Citation

CHEN Bao-Qiu and MA Zhong-Yu. Effect of Proximity Force on Potential Barrier in Fusion Reaction[J]. Chinese Physics C, 2004, 28(10): 1079-1082.

CHEN Bao-Qiu and MA Zhong-Yu. Effect of Proximity Force on Potential Barrier in Fusion Reaction[J]. Chinese Physics C, 2004, 28(10): 1079-1082. shu

RIS(for EndNote,Reference Manager,ProCite)

BibTex

Txt

Milestone

Received: 2004-02-25
Revised: 1900-01-01

Article Metric

Article Views(3944)
PDF Downloads(504)
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

Effect of Proximity Force on Potential Barrier in Fusion Reaction

Corresponding author: CHEN Bao-Qiu,

Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000,China2 China Institute of Atomic Energy,Beijing 102413,China3 Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100080,China

Received Date: 2004-02-25

Accepted Date: 1900-01-01

Available Online: 2004-10-05

Abstract: The macroscopic deformed potential energies for fusion reactions are determined within a generalized liquid drop model (GLDM) which includes the volume—,surface,and Coulomb energies,the proximity effects,the mass asymmetry,and an accurate nuclear radius. In ordinary fission studies,it is assumed that the surface and Coulomb energies control the hight and width of the barrier. The surface energy E_S takes into account only the effect of the surface tension force and does not include the contribution of the attractive nuclear forces between surfaces in regard to the neck or the gap between the nascent fragments. The nuclear proximity energy is adopted to take into account these additional surface effects in general liquid drop model. At the contact point,the proximity energy reaches maximum while it decreases both sides till to zero. The proximity energy decreases the barrier height by several MeV and moves the position of the barrier top forward,which corresponds to two separated fragments in unstable equilibrium by the balance between the attractive nuclear proximity force and the repulsive Coulomb force in the GDLM. It turns out that a wide macroscopic potential pocket in fusion process is formed due to proximity energy and appears at large deformation. This behavior does not appear at the barrier for the fusion reaction of light nucleus nucleus collision.

HTML

Reference (1)

Effect of Proximity Force on Potential Barrier in Fusion Reaction

Abstract：

References

Access

Article Metrics

Metrics

通讯作者: 陈斌, bchen63@163.com

Email This Article