11 research outputs found
Observing Non-Gaussian Sources in Heavy-Ion Reactions
We examine the possibility of extracting non-Gaussian sources from
two-particle correlations in heavy-ion reactions. Non-Gaussian sources have
been predicted in a variety of model calculations and may have been seen in
various like-meson pair correlations. As a tool for this investigation, we have
developed an improved imaging method that relies on a Basis spline expansion of
the source functions with an improved implementation of constraints. We examine
under what conditions this improved method can distinguish between Gaussian and
non-Gaussian sources. Finally, we investigate pion, kaon, and proton sources
from the p-Pb reaction at 450 GeV/nucleon and from the S-Pb reaction at 200
GeV/nucleon studied by the NA44 experiment. Both the pion and kaon sources from
the S-Pb correlations seem to exhibit a Gaussian core with an extended,
non-Gaussian halo. We also find evidence for a scaling of the source widths
with particle mass in the sources from the p-Pb reaction.Comment: 16 pages, 15 figures, 5 tables, uses RevTex3.
Interferometry with Resonances and Flow in High-Energy Nuclear Collisions
The effects of resonances and flow on the correlation function for two
identical particles are described assuming chaotic sources and classical
propagation of particles. Expanding to second order in relative momenta, the
source sizes can be calculated directly and understood as contributions from
various fluctuations in the source. Specific calculations of source size radii
are given assuming Bjorken longitudinal flow with additional transverse
expansion. Results are compared to recent and correlation data
from relativistic nuclear collisions with particular attention to the reduction
in the correlation function due to resonances and the decreasing
source sizes with increasing transverse momenta of the particles.Comment: 8 pages including 2 figure