标题： SIS能区的K介子与反K介子产生对比 显示英文标题

标题： Kaon versus Antikaon Production at SIS Energies

摘要： 我们分析了在Ni + Ni反应中，从0.8到1.85 GeV/u的能量范围内，K介子和反K介子的产生与传播，采用了一种耦合通道输运方法，其中包含了通道$BB \to K^+YN, \pi B\to K^+Y, BB \to NN K \bar{K}, \pi B\to N K\bar{K}, K^+B\to K^+B, \bar{K} B\to \bar{K}B, Y N\to \bar{K} NN, \pi \pi\to K \bar{K}$以及$\pi Y\to \bar{K}N$和$\bar{K} N\to \pi Y$来描述反K介子吸收。 虽然在0.8到1.8 GeV/u的Ni + Ni碰撞中，实验测量的$K^+$谱可以被重现而无需引入任何介子的自能，但$K^-$的产额在1.66和1.85 GeV/u时低估了5到7倍。 然而，引入Kaplan和Nelson提出的密度依赖性反K介子质量后，反K介子谱可以得到合理的描述。 显示英文摘要

摘要： We analyse the production and propagation of kaons and antikaons in Ni + Ni reactions from 0.8--1.85 GeV/u within a coupled channel transport approach including the channels $BB \to K^+YN, \pi B\to K^+Y, BB \to NN K \bar{K}, \pi B\to N K\bar{K}, K^+B\to K^+B, \bar{K} B\to \bar{K}B, Y N\to \bar{K} NN, \pi \pi\to K \bar{K}$ as well as $\pi Y\to \bar{K}N$ and $\bar{K} N\to \pi Y$ for the antikaon absorption. Whereas the experimental $K^+$ spectra can be reproduced without introducing any selfenergies for the mesons in Ni + Ni collisions from 0.8 to 1.8 GeV/u, the $K^-$ yield is underestimated by a factor of 5--7 at 1.66 and 1.85 GeV/u. However, introducing density dependent antikaon masses as proposed by Kaplan and Nelson, the antikaon spectra can be reasonably well described.