Event-by-event fluctuations of the kaon-to-pion ratio in central Pb plus Pb collisions at 158 GeV per nucleon

Afanasiev, SV Anticic, T Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H Billmeier, A Blume, C Blyth, CO Boimska, B Botje, M Bracinik, J Brady, FP Bramm, R Brun, R Buncic, P Carr, L Cebra, D Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F Ferenc, D Filip, P Fischer, HG Fodor, Z Foka, P Freund, P Friese, V Ftacnik, J Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E Harris, JW Hegyi, S Hlinka, V Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R Jones, PG Kadija, K Kolesnikov, VI Kollegger, T Kowalski, M Lasiuk, B van Leeuwen, M Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Mischke, A Molnar, J Nelson, JM Odyniec, G Palla, G Panagiotou, AD Petridis, A Pikna, M Pinsky, L Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandoval, A Sann, H Schafer, E Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E Snellings, R Squier, GTA Stock, R Strmen, P Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S Wetzler, A Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J

Sv. Afanasiev et al., Event-by-event fluctuations of the kaon-to-pion ratio in central Pb plus Pb collisions at 158 GeV per nucleon, PHYS REV L, 86(10), 2001, pp. 1965-1969

16

INGLESE

Article

Physics

PHYSICAL REVIEW LETTERS

0031-9007 → ACNP

86

10

2001

1965 - 1969

ISI

0031-9007(20010305)86:10<1965:EFOTKR>2.0.ZU;2-R

We present the first measurement of fluctuations from event to event in the production of strange particles in collisions of heavy nuclei. The ratio o f charged kaons to charged pions is determined for individual central Pb Pb collisions. After accounting for the fluctuations due to detector resolu tion and finite number statistics we derive ant upper limit on genuine nons tatistical fluctuations, which could be related to a first- or second-order QCD phase transition. Such fluctuations Lire shown to be very small.