每核子158 GeV的Pb-Au碰撞中的e+e-对产生
核实验
2011-09-13 v1
摘要
我们给出了1995年和1996年在CERN SPS上获取的158 GeV/n {Pb-Au}（√s = 17.2 GeV）碰撞中电子对产生的合并结果，并详细说明了数据分析。当中性介子衰变的参考谱被积分到不变质量m > 200 MeV/c^2时，对于半中心碰撞（28% σ/σ_geo），其超出参考谱的增强因子为2.31±0.19 (stat.)±0.55 (syst.)±0.69 (decays)。所测产额、其比线性更强的随N_ch的标度行为，以及低对横动量p_t的主导地位，强烈暗示可将其解释为强子火球中π介子湮灭发出的热辐射。然而，以m≈500 MeV/c^2为中心的超出部分的形状，若不对ρ介子作强烈的介质修正则无法描述。通过与由手征对称性恢复主导的Brown-Rho标度以及谱函数多体处理（其中对相边界的逼近较不明确）的预测相比较，将这些结果置于整体视角中。
引用
@article{arxiv.nucl-ex/0506002,
title = {e+e--pair production in Pb-Au collisions at 158 GeV per nucleon},
author = {G. Agakichiev and H. Appelshauser and J. Bielcikova and R. Baur and P. Braun-Munzinger and A. Cherlin and S. Damjanovic and A. Drees and S. Esumi and U. Faschingbauer and Z. Fraenkel and Ch. Fuchs and E. Gatti and P. Glassel and G. Hering and C. P. de los Heros and P. Holl and Ch. Jung and B. Lenkeit and A. Marin and F. Messer and M. Messer and D. Miskowiec and O. Nix and Yu. Panebrattsev and A. Pfeiffer and J. Rak and I. Ravinovich and S. Razin and P. Rehak and M. RIchter and M. Sampietro and H. Sako and N. Saveljic and W. Schmitz and J. Schukraft and W. Seipp and S. Shimanskiy and E. Socol and H. J. Specht and J. Stachel and G. Tel-Zur and I. Tserruya and T. Ullrich and C. Voigt and S. Voloshin and C. Weber and J. P. Wessels and T. Wienold and J. P. Wurm and V. Yurevich},
journal= {arXiv preprint arXiv:nucl-ex/0506002},
year = {2011}
}
备注
39 pages, 40 figures, to appear in Eur.Phys.J.C. (2005)