Journal article
Authors list: Agakichieva, G; Appelshäuser, H; Bielcikova, J; Baur, R; Braun-Munzinger, P; Cherlin, A; Damjanovic, S; Drees, A; Esumi, S; Faschingbauer, U; Fraenkel, Z; Fuchs, C; Gatti, E; Glässel, P; Hering, G; Heros, CPD; Holl, P; Jung, C; Lenkeit, B; Marín, A; Messer, F; Messer, M; Miskowiec, D; Nix, O; Panebrattsev, Y; Pfeiffer, A; Rak, J; Ravinovich, I; Razin, S; Rehak, P; Richter, M; Sampietro, M; Sako, H; Saveljic, N; Schmitz, W; Schukraft, J; Seipp, W; Shimanskiy, S; Socol, E; Specht, HJ; Stachel, J; Tel-Zur, G; Tserruya, I; Ullrich, T; Voigt, C; Voloshin, S; Weber, C; Wessels, JP; Wienold, T; Wurm, JP; Yurevich, V
Publication year: 2005
Pages: 475-513
Journal: The European Physical Journal C
Volume number: 41
Issue number: 4
ISSN: 1434-6044
eISSN: 1434-6052
DOI Link: https://doi.org/10.1140/epjc/s2005-02272-3
Publisher: SpringerOpen
Abstract:
We present the combined results on electron-pair production in 158 GeV/n Pb-Au (root s= 17.2 GeV) collisions taken at the CERN SPS in 1995 and 1996, and give a detailed account of the data analysis. The enhancement over the reference of neutral meson decays amounts to a factor of 2.31 +/- 0.19 ( stat.) +/- 0.55 ( syst.) +/- 0.69 ( decays) for semi-central collisions ( 28% sigma/sigma(geo)) when yields are integrated over m > 200 MeV/c(2) in invariant mass. The measured yield, its stronger-than-linear scaling with N-ch, and the dominance of low pair p(t) strongly suggest an interpretation as thermal radiation from pion annihilation in the hadronic fireball. The shape of the excess centring at m approximate to 500 MeV/c(2), however, cannot be described without strong medium modi. cations of the. meson. The results are put into perspective by comparison to predictions from Brown-Rho scaling governed by chiral symmetry restoration, and from the spectral-function many-body treatment in which the approach to the phase boundary is less explicit.
Citation Styles
Harvard Citation style: Agakichieva, G., Appelshäuser, H., Bielcikova, J., Baur, R., Braun-Munzinger, P., Cherlin, A., et al. (2005) e+e- -pair production in Pb-Au collisions at 158 GeV per nucleon, The European Physical Journal C, 41(4), pp. 475-513. https://doi.org/10.1140/epjc/s2005-02272-3
APA Citation style: Agakichieva, G., Appelshäuser, H., Bielcikova, J., Baur, R., Braun-Munzinger, P., Cherlin, A., Damjanovic, S., Drees, A., Esumi, S., Faschingbauer, U., Fraenkel, Z., Fuchs, C., Gatti, E., Glässel, P., Hering, G., Heros, C., Holl, P., Jung, C., Lenkeit, B., ...Yurevich, V. (2005). e+e- -pair production in Pb-Au collisions at 158 GeV per nucleon. The European Physical Journal C. 41(4), 475-513. https://doi.org/10.1140/epjc/s2005-02272-3
Keywords
CHIRAL-SYMMETRY RESTORATION; DILEPTON PRODUCTION; ELECTRON-PAIR PRODUCTION; FINITE-TEMPERATURE; FREEZE-OUT; PB+PB COLLISIONS; QCD PHASE-TRANSITION; RHO-MESON; SPECTRAL-FUNCTION; VECTOR-MESONS
