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

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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

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[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.
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[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.

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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

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Received: 2004-02-25
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

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.

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Effect of Proximity Force on Potential Barrier in Fusion Reaction

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