Back B B, Betts R R, Chang J, Chang W C, Chi C Y, Chu Y Y, Cumming J B, Dunlop J C, Eldredge W, Fung S Y, Ganz R, Garcia E, Gillitzer A, Heintzelman G, Henning W F, Hofman D J, Holzman B, Kang J H, Kim E J, Kim S Y, Kwon Y, McLeod D, Mignerey A C, Moulson M, Nanal V, Ogilvie C A, Pak R, Ruangma A, Russ D E, Seto R, Stanskas P J, Stephans G S, Wang H, Wolfs F L, Wuosmaa A H, Xiang H, Xu G H, Yao H B, Zou C M
Argonne National Laboratory, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2001 Dec 10;87(24):242301. doi: 10.1103/PhysRevLett.87.242301. Epub 2001 Nov 19.
We present results for antilambda and antiproton production in Au+Au collisions at 11.7 A GeV/c including spectra and extracted invariant yields for both species in central and peripheral collisions in the rapidity range 1.0<y<1.4. The antilambda yield increases from dN(Lambda;)/dy = 1.2(+0.7+0.2)(-0.6-0.2)x10(-3) in peripheral collisions to 19(+4+3)(-5-2)x10(-3) in central collisions. The direct antiproton yield is deduced from the measured total antiproton spectra to extract the ratio of antilambda-to-direct-antiproton production. The Lambda/p ratio near midrapidity increases from 0.26(+0.19+0.5)(-0.15-0.4) in peripheral collisions to 3.6(+4.7+2.7)(-1.8-1.1) in central collisions, a value larger than current theoretical estimates.
我们展示了在11.7 A GeV/c的金离子与金离子碰撞中反Λ粒子和反质子产生的结果，包括中心碰撞和周边碰撞中两种粒子在快度范围1.0<y<1.4内的谱以及提取的不变产额。反Λ粒子产额从周边碰撞中的dN(Λ̅)/dy = 1.2(+0.7 + 0.2)(-0.6 - 0.2)×10⁻³增加到中心碰撞中的19(+4 + 3)(-5 - 2)×10⁻³。从测量的总反质子谱中推导出直接反质子产额，以提取反Λ粒子与直接反质子产生的比率。快度中点附近的Λ̅/p比率从周边碰撞中的0.26(+0.19 + 0.5)(-0.15 - 0.4)增加到中心碰撞中的3.6(+4.7 + 2.7)(-1.8 - 1.1)，该值大于目前的理论估计。
