Necrotising Enterocolitis - epidemiology and imaging

Mass shift and width broadening of ρ-mesons produced in heavy ion collisions

“…In the experiment on S + S collisions at 200 GeV·A [15] it was found that p cm LN = 3.3 GeV, p T N = 0.61 GeV, and p cm Lπ ≈ 0.70 GeV, p T π ≈ 0.36 GeV. In other experiments on high energy heavy ion collisions -see [16,17] -the situation is qualitatively similar. This means that one can by no means speak about a thermal gas of final particles in global equilibrium, and their momentum distributions must be taken from experiment.…”

Au+Au reactions at the AGS: Experiments E866 and E917

“…Experiments E866 and E917 at the AGS aim to characterize as fully as possible the emission of particles from Au+Au collisions to probe the properties of such dense matter. In Quark Matter '96 [1] the E866 collaboration reported that the proton rapidity distribution for central collisions is peaked at mid-rapidity [2]. This is consistent with forming a dense, baryon-rich system.…”

“…The transverse m t spectra of different particles have different spectral shapes, with an overall trend that the proton spectra have larger inverse slopes than the kaon spectra, which in turn have larger inverse slopes than the pion spectra. Detailed analysis [1,2] revealed that the π − transverse spectra have a low p t rise above an exponential that is steeper than the rise in π + spectra. Such features originate from the interplay between multiple collisions of hadrons, expansion of the system, decay of resonances and Coulomb effects.…”

Evidence for different freeze-out radii of high- and low-energy pions emitted in Au+Au collisions at 1 A·GeV

“…Recently π − /π + -ratios have also been measured at much higher bombarding energies. In Au+Au collisions at 10.7 A·GeV the π − /π + -ratio is found to be 1.5 for low transverse momenta p T and it approaches unity at higher p T [24]. In Pb+Pb collisions at 158 A·GeV the π − /π + -ratio exceeds one only for very small values of p T .…”