24 research outputs found
Fluctuations of the azimuthal particle distribution in NA49 at the CERN SPS
Event-by-event fluctuations and correlations in azimuthal angle are currently
widely investigated in various experiments. In this paper the measure
(earlier used in experiments to evaluate fluctuations in transverse momentum)
is now applied to azimuthal angle . Properties of this
function are investigated through fast generators and with complex models such
as Pythia, Hijing, and UrQMD. Preliminary results of NA49 on are
also presented. The system size dependence (p+p, C+C, Si+Si and 6 centralities
of Pb+Pb) at the highest SPS energy (158 GeV) is shown, as well as the
energy dependence (20 - 158 GeV) for the 7.2\% most central Pb+Pb
interactions.Comment: Proceedings from Hot Quarks 2010,June 21-2
Strangeness Suppression in Proton-Proton Collisions
We analyse strangeness production in proton-proton (pp) collisions at SPS and
RHIC energies, using the recently advanced NeXus approach. After having
verified that the model reproduces well the existing data, we interpret the
results: strangeness is suppressed in proton-proton collisions at SPS energy as
compared to electron-positron (e+e-) annihilation due to the limited masses of
the strings produced in the reaction, whereas high energy pp and e+e-
collisions agree quantitatively . Thus strangeness suppression at SPS energies
is a consequence of the limited phase-space available in string fragmentation.Comment: 7 Figures, 4 Page