Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions

YE YunXiu; CHEN Zhi; RUAN TuNan; SHEN Ji; LV HaiJiang; DONG WeiJiang; SA BenHao; TAI An

Chinese Physics C> 2000, Vol. 24> Issue(2) : 125-130

Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions

Department of Modern Physics, Univsity of Science and Technology of China, Hefei 230026, China2 CCAST World Laboratory, Beijing 100080, China3 China Institute of Atomic Energy, Beijing 102413, China4 Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100039, China

Abstract
HTML
Reference
Related

PDF

Abstract：
The degradation of Λ transverse polarization produced in S+Pb central collisions at energy 200 GeV per nucleon has been studied in detail. The S+Pb central collision events have been generated using Monte-Carlo generator——LUCIAE at 200 GeV per nucleon. The various factors degrading Λ transverse polarization have been analysed quantitatively. The ratios of Λ′s produced from rescattering, secondary production and decays of Σ, Ξ hyperons to the total measurable Λ′s in experiment have been investigeted and the degradation effect of these Λ on the total polarization has been determined. The simulation and calculation show that above three factors decrease the Λ transverse polarization strongly, however, can not eliminate the polarization completely when the Λ′s are assumed to be produced from hadronic gas in the final state. To explan the experimental data of vanished Λ polarization, it probably needs to consider new mechanisms of Λ production, including a weak effect of QGP formation.

References

[1]

. Gourlay S A,Melanson H L,Abolins M A et al.Phys.Rev.Lett.,1986,56:2244—22472. Aahlin P,Frodesen A G,Alpgare K et al.Lett.Nuov.Cimento,1978,21:236—2383. Abe F,Hara K,Kimetal S et al.Phys.Rev.,1986,D34:1950—19594. Anikina M,Aksineko V,Dementiev E et al.Z.Phys.,1984,C25:1—115. Harris J W,Sandoval A,StockR et al.Phys.Rev.Lett.,1981,47:229—2346. Anderson B,Gustafson G,Ingelman G et al.Phys.Rep.,1983,97:31—1457. DeGrand T A,Markkanen J,Miettinen H I.Phys.Rev.,1985,D32:2445—24488. Szwed J.Phys.Lett.,1981,B105:403—4059. Heller K,Cox P T,Dworkin J et al.Phys.Rev.Lett.,1978,41:607—61010. Satz H.Ann.Rev.Nucl.Par.Sci.,1985,35:245-270;Casher A,Neuberger H et al.Phys.Rev.,1979,D20:179—18811. Panagiotou A D.Phys.Rev.,1986,C33:1999—200212. Stock R,Angert N,Bialkowska H et al.Quark Matter Formation and Heavy Ion Collisions,World Scientific,Singapore,1982,557—58213. Bartke J,Bialkowska H,Bock R et al.Z.Phys.,1990,C48:191—20014. YE YunXiu,SU SuFang,ZHOU Xin et al.High Energy Phys.and Nucl.Phys.,(in Chinese),1996,20:685—690(叶云秀,苏淑芳,周昕等.高能物理与核物理,1996,20:685—690)15. Miyano K,Noguchi Y,Fukawa M et al.Phys.Rev.Lett.,1984,53:1725—172716. SA BenHao,TAI An.Comp.Phys.Commu.,1995,90:121—14017. Andersson B,Gustafson G,Hong Pi.Z.Phys.,1993,C57:485—49418. Andersson B,TAI A.Z.Phys.,1996,C31:15519. SA BenHao,WANG ZhongQi,ZHANG XiaoZe et al.Phys.Rev.,1993,C48:2995—2998

[1]	Selyuzhenkov . Λ-Hyperon Global Polarization in Au+Au Collisions at RHIC. Chinese Physics C, 2007, 31(12): 1185-1188.
[2]	MENG Cai-Rong . Proton rapidity distribution in nucleus-nucleus collisions at high energy. Chinese Physics C, 2006, 30(4): 322-326.
[3]	NING Ping-Zhi , TAN Yu-Hong LI Lei , LUO Yan-An , . Relativistic Mean Field Theory for Hypernuclei. Chinese Physics C, 2004, 28(12): 1336-1342.
[4]	SA Ben-Hao , WANG Zhong-Qi , SU Zong-Di , LU Zhong-Dao , ZHOU Dai-Mei . Φ Meson Production and String Fragmentation Function in Relativistic Nucleus-Nucleus Collisions. Chinese Physics C, 2003, 27(2): 147-149.
[5]	SA Ben-Hao , WANG Xiao-Rong , LU Zhong-Dao , SU Zong-Di , CAI Xu . Enhancement of φ Mesons in Relativistic Nucleus-Nucleus Collisions. Chinese Physics C, 2002, 26(4): 387-392.
[6]	LIU Shu-Xin , YU Lei , LEI Yi-An , ZENG Jin-Yan . Investigation of the Type of Quadrupole Pairing Force in Superdeformed Nuclei. Chinese Physics C, 2001, 25(1): 37-43.
[7]	HE ZeJun , JIANG WeiZhou , ZHU ZhiYuan , LIU Bo , ZHANG JiaJu . A Signature for the Formation of the Quark-Gluon Plasma in Nucleus-Nucleus Collisions. Chinese Physics C, 2000, 24(5): 462-466.
[8]	Tai An , Sa Benhao . Reduction of Strange Quark Suppression in Relativistic Nucleus-Nucleus Collisions. Chinese Physics C, 1998, 22(5): 434-439.
[9]	Shen Yaosong , Ren Zhongzhou . Relativistic Mean-Field Calculation for Hypernuclei. Chinese Physics C, 1997, 21(9): 831-837.
[10]	Zhu Zhiyuan . Identical Bands in Superdeformed Nuclei With the Cranked Relativistic Mean Field Method. Chinese Physics C, 1996, 20(5): 448-454.
[11]	Ye Yunxiu , Su Shufang , Zhou Xin , Zhu Guohuai , Ji Gang . The Correlation Between the Transverse Polarization andTransverse Momentum of Lambda Produced in RelativisticNucleus-Nucleus Collisions. Chinese Physics C, 1996, 20(8): 685-690.
[12]	Sa Benhao , Tai An , Lu Zhongdao . Strange Baryon and the Signal of QGP Formation in Ultrarelativistic Nucleus-Nucleus Collisions. Chinese Physics C, 1995, 19(11): 1019-1023.
[13]	Bai Ge , Li Jiarong . High Energy Unequi-Nuclei Collision and Relaxation Time in a Relativistic Kinetic Equation. Chinese Physics C, 1994, 18(2): 166-171.
[14]	Wang Zhongqi , Sa Benhao , Song Guang , Lu Zhongdao , Zhang Xiaoze , Zheng Yuming . Hadronic Transport Model Explanation of K⁺/π⁺ Ratio in Relativistic Nucleus-nucleus Collisions. Chinese Physics C, 1994, 18(8): 741-744.
[15]	Liu Fuhu , Tang Xiaowei . Multiplicity and Angular Distribution of Projectile Fragments in Relativistic Nucleus-Nucleus Collisions. Chinese Physics C, 1994, 18(4): 334-339.
[16]	QIAN Lu . Distribution in Ultrarelativistic Nuclear Collisions. Chinese Physics C, 1991, 15(10): 906-912.
[17]	JIANG De-Bao , HE Ze-Jun . Evolution of Strangeness in an Expanding Quark-Gluon Plasma Formed by Ultrarelativistic Nucleus-Collisions. Chinese Physics C, 1991, 15(5): 450-456.
[18]	CHEN Jun-Feng , HE Ze-Jun . THE CHARACTERISTIC DILEPTON MASS DISTRIBUTION FROM HOT QUARK MATTER IN ULTRARELATIVISTIC NUCLEUS-NUCLEUS COLLISIONS. Chinese Physics C, 1990, 14(4): 359-365.
[19]	ZHAO Wei-Qin , LIU Bo . MULTIPLICITY DISTRIBUTION AND NUCLEAR GEOMETRY IN RELATIVISTIC HEAVY ION COLLISIONS. Chinese Physics C, 1989, 13(3): 285-288.
[20]	LIU Bo , WANG Ying-Cai . MULTIPLICITY DISTRIBUTIONS OF PRODUCED PARTICLES AND ENERGY LOSS IN PROTON-NUCLEUS COLLISIONS AT 200GeV/c. Chinese Physics C, 1987, 11(2): 231-237.

Access

Get Citation

YE YunXiu, CHEN Zhi, RUAN TuNan, SHEN Ji, LV HaiJiang, DONG WeiJiang, SA BenHao and TAI An. Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions[J]. Chinese Physics C, 2000, 24(2): 125-130.

RIS(for EndNote,Reference Manager,ProCite)

BibTex

Txt

Milestone

Received: 1998-12-17
Revised: 1900-01-01

Article Metric

Article Views(4312)
PDF Downloads(737)
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

Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions

Corresponding author: YE YunXiu,

Department of Modern Physics, Univsity of Science and Technology of China, Hefei 230026, China2 CCAST World Laboratory, Beijing 100080, China3 China Institute of Atomic Energy, Beijing 102413, China4 Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100039, China

Received Date: 1998-12-17

Accepted Date: 1900-01-01

Available Online: 2000-02-05

Abstract: The degradation of Λ transverse polarization produced in S+Pb central collisions at energy 200 GeV per nucleon has been studied in detail. The S+Pb central collision events have been generated using Monte-Carlo generator——LUCIAE at 200 GeV per nucleon. The various factors degrading Λ transverse polarization have been analysed quantitatively. The ratios of Λ′s produced from rescattering, secondary production and decays of Σ, Ξ hyperons to the total measurable Λ′s in experiment have been investigeted and the degradation effect of these Λ on the total polarization has been determined. The simulation and calculation show that above three factors decrease the Λ transverse polarization strongly, however, can not eliminate the polarization completely when the Λ′s are assumed to be produced from hadronic gas in the final state. To explan the experimental data of vanished Λ polarization, it probably needs to consider new mechanisms of Λ production, including a weak effect of QGP formation.

HTML

Reference (1)

Exploration for Degradation of Λ Polarization Produced in Relativistic Nucleus Nucleus Collisions

Abstract：

References

Access

Article Metrics

Metrics

通讯作者: 陈斌, bchen63@163.com

Email This Article