标题： ${\barΛ}/{\bar p}$在11.6 AGeV/c能区的重离子碰撞中的比值 显示英文标题

标题： ${\barΛ}/{\bar p}$ ratios in heavy ion collisions at 11.6 AGeV/c

摘要： 我们试图在强子框架内解释在$11.6~{\rm A\cdot GeV}/c$束流动量下重离子碰撞中测量的${\bar \Lambda}/\bar p$比率。 该比率相对于$pp$碰撞中的相应比率有所增强，并且与重离子数据的热拟合相比要大得多。 通过详细的级联计算，我们表明$\bar \Lambda$和$\bar p$的不同湮灭截面以及$\bar p$到$\bar \Lambda$的净转换，无法解释中心碰撞中的增强现象。 然而，对于较大的碰撞参数，强子机制可能足以产生观察到的增强。 考虑了基本截面和形成时间的不确定性。 显示英文摘要

摘要： We attempt to explain the ${\bar \Lambda}/\bar p$ ratios measured in heavy ion collisions at $11.6~{\rm A\cdot GeV}/c$ beam momentum within a hadronic framework. This ratio is enhanced relative to corresponding ratios in $pp$ collisions, and is large when compared with thermal fits to heavy ion data. Using a detailed cascade calculation, we show that different annihilation cross--sections of $\bar \Lambda$'s and $\bar p$'s, and the net conversion of $\bar p$'s to $\bar \Lambda$'s, do not account for the enhancement in central collisions. For larger impact parameters, however, hadronic mechanisms may well suffice to produce the observed enhancement. Uncertainties in elementary cross--sections and formation times are considered.