A. Agnihotri | Searcharxiv

arXiv2000

Localized Charged-Neutral Fluctuations in 158 A GeV Pb+Pb Collisions

First results on the measurement of localized fluctuations in the multiplicity of charged particles and photons produced in central 158 A GeV Pb+Pb collisions are presented. The charged versus neutral correlations in common phase space regions of varying azimuthal size are analyzed by two different methods. The measured results are compared to those from simulations and to those from different types of mixed events. The comparison indicates the presence of non-statistical fluctuations in both charged particle and photon multiplicities in limited azimuthal regions. However, no correlated charge-neutral fluctuations are observed.

nucl-ex↗

arXiv1998

A Preshower Photon Multiplicity Detector for the WA98 Experiment

A high granularity preshower detector has been fabricated and installed in the WA98 Experiment at the CERN SPS for measuring the spatial distribution of photons produced in the forward region in lead ion induced interactions. Photons are counted by detecting the preshower signal in plastic scintillator pads placed behind a 3 radiation length thick lead converter and applying a threshold on the scintillator signal to reject the minimum ionizing particles. Techniques to improve the imaging of the fibre and performance of the detector in the high multiplicity environment of lead-lead collisions are described. Using Monte-Carlo simulation methods and test beam data of pi- and e- at various energies the photon counting efficiency is estimated to be 68% for central and 73% for peripheral Pb+Pb collisions.

hep-ex↗