Kaon Phase Space Density in Heavy Ion Collisions

The first measurement of kaon phase space densities are presented as a function of transverse mass, center of mass energy and the number of participants. The kaon phase space density increases with the number of participants from e+e- to Pb+Pb collisions. However the ratio of the kaon and pion phase space densities at low transverse momentum is independent of the number of participants for sqrt{s}=17GeV/nucleon This paper is dedicated to Francis Riccardelli, engineer for the Port Authority, who died on September 11th 2001 while evacuating others.Comment: 4 pages, 2 eps figures, proceedings of Strange Quarks in Matter, Frankfurt 2001, submitted to J. Phys. G In response to referees comments I derived an expresion for the ratio of kaon and pion phase space densites and made several clarifications in the tex

Bose-Einstein Correlations for Three-Dimensionally Expanding, Cylindrically Symmetric, Finite Systems

The parameters of the Bose-Einstein correlation function may obey an {\it $M_t$-scaling}, as observed in $S + Pb$ and $Pb + Pb$ reactions at CERN SPS. This $M_t$-scaling implies that the Bose-Einstein correlation functions view only a small part of the big and expanding system. The full sizes of the expanding system at the last interaction are shown to be measurable with the help the invariant momentum distribution of the emitted particles. A vanishing duration parameter can also be generated in the considered model-class with a specific $M_t$ dependence.Comment: 35 pages, ReVTeX, LaTeX, no figures, discussion extende

Source Dimensions in Ultrarelativistic Heavy Ion Collisions

Recent experiments on pion correlations, interpreted as interferometric measurements of the collision zone, are compared with models that distinguish a prehadronic phase and a hadronic phase. The models include prehadronic longitudinal expansion, conversion to hadrons in local kinetic equilibrium, and rescattering of the produced hadrons. We find that the longitudinal and outward radii are surprisingly sensitive to the algorithm used for two-body collisions. The longitudinal radius measured in collisions of 200 GeV/u sulfur nuclei on a heavy target requires the existence of a prehadronic phase which converts to the hadronic phase at densities around 0.8-1.0 GeV/fm$^3$. The transverse radii cannot be reproduced without introducing more complex dynamics into the transverse expansion.Comment: RevTeX 3.0, 28 pages, 6 figures, not included, revised version, major change is an additional discussion of the classical two-body collision algorithm, a (compressed) postscript file of the complete paper including figures can be obtained from Authors or via anonymous ftp at ftp://ftp_int.phys.washington.edu/pub/herrmann/pisource.ps.

Strange Meson Enhancement in PbPb Collisions

The NA44 Collaboration has measured yields and differential distributions of K+, K-, pi+, pi- in transverse kinetic energy and rapidity, around the center-of-mass rapidity in 158 A GeV/c Pb+Pb collisions at the CERN SPS. A considerable enhancement of K+ production per pi is observed, as compared to p+p collisions at this energy. To illustrate the importance of secondary hadron rescattering as an enhancement mechanism, we compare strangeness production at the SPS and AGS with predictions of the transport model RQMD.Comment: 11 pages, including 4 figures, LATE

One and two dimensional analysis of 3pi correlations measured in Pb+Pb interactions

3pi- correlations from Pb+Pb collisions at 158 GeV/c per nucleon are presented as measured by the focusing spectrometer of the NA44 experiment at CERN. The three-body effect is found to be stronger for PbPb than for SPb. The two-dimensional three-particle correlation function is also measured and the longitudinal extension of the source is larger than the transverse extension

Two-Proton Correlations from 14.6A GeV/c Si+Pb and 11.5A GeV/c Au+Au Central Collisions

Two-proton correlation functions have been measured in Si+Pb collisions at 14.6A GeV/c and Au+Au collisions at 11.5A GeV/c by the E814/E877 collaboration. Data are compared with predictions of the transport model RQMD and the source size is inferred from this comparison. Our analysis shows that, for both reactions, the characteristic size of the system at freeze-out exceeds the size of the projectile, suggesting that the fireball created in the collision has expanded. For Au+Au reactions, the observed centrality dependence of the two-proton correlation function implies that more central collisions lead to a larger source sizes.Comment: RevTex, 12 pages, 5 figure

A new VME trigger processor for the NA57 experiment

The ALICE experiment will use a trigger concept requiring independent deadtimes for each sub-detector system, and with detector-specific past-future protection. These features are implemented in a new VME-based trigger processor for the NA57 experiment. Monitoring and diagnostic features of the new trigger processor are also described.List of Figures Figure 1:ALICE trigger logic diagram. Figure 2:Layout of the NA57 experiment. Figure 3:Schematic layout of NA57 VME central trigger processor. Figure 4:Example of a trigger definition script. </A

Scientific Objectives of Einstein Telescope

The advanced interferometer network will herald a new era in observational astronomy. There is a very strong science case to go beyond the advanced detector network and build detectors that operate in a frequency range from 1Hz to 10kHz, with sensitivity a factor 10 better in amplitude. Such detectors will be able to probe a range of topics in nuclear physics, astronomy, cosmology and fundamental physics, providing insights into many unsolved problems in these areas