Search for Disoriented Chiral Condensates in 158 AGeV Pb+Pb Collisions

TL;DR

This study searched for Disoriented Chiral Condensates in high-energy lead-lead collisions but found no evidence, setting upper limits on their possible production based on experimental data.

Contribution

The paper provides the first experimental search for DCC in 158 AGeV Pb+Pb collisions and establishes upper limits on DCC production using a large dataset.

Findings

No clear DCC signal detected

Set 90% confidence level upper limits on DCC production

Analyzed over 210,000 collision events

Abstract

The restoration of chiral symmetry and its subsequent breaking through a phase transition has been predicted to create regions of Disoriented Chiral Condensates (DCC). This phenomenon has been predicted to cause anomalous fluctuations in the relative production of charged and neutral pions in high-energy hadronic and nuclear collisions. The WA98 experiment has been used to measure charged and photon multiplicities in the central region of 158 AGeV Pb+Pb collisions at the CERN SPS. In a sample of 212646 events, no clear DCC signal can be distinguished. Using a simple DCC model, we have set a 90% C.L. upper limit on the maximum DCC production allowed by the data.