Partial U(1){sub {ital A}} restoration and {eta} enhancement in high-energy heavy-ion collisions

Journal Article · Wed May 01 04:00:00 EDT 1996 · Physical Review, D

DOI:https://doi.org/10.1103/PhysRevD.53.5034· OSTI ID:284066

Huang, Z ^[1]; Wang, X ^[2]

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1. Theoretical Physics Group, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 (United States)
2. Nuclear Science Division, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 (United States)

We calculate the thermally averaged rates for {eta}-{pi} conversion and {eta} scattering using the Di Vecchia{endash}Veneziano and {close_quote}t Hooft models, which incorporate explicitly the U(1){sub {ital A}} anomaly. Assuming an exponential suppression of the U(1){sub {ital A}} anomaly, we also take into account the partial restoration of U(1){sub {ital A}} symmetry at high temperatures. We find that the chemical equilibrium between {eta} and {pi} breaks up considerably earlier than the thermal equilibrium. Two distinct scenarios for the {eta} freeze-out are discussed and the corresponding chemical potentials are calculated. We predict an enhancement of the thermal {eta} production as a possible signal of the partial U(1){sub {ital A}} restoration in central high-energy heavy-ion collisions. {copyright} {ital 1996 The American Physical Society.}

• Research Organization: Lawrence Berkeley National Laboratory
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 284066
• Journal Information: Physical Review, D, Journal Name: Physical Review, D Journal Issue: 9 Vol. 53; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CONVERSION
ETA MESONS
FREEZING OUT
HEAVY ION REACTIONS
PIONS
THERMAL EQUILIBRIUM
U-1 GROUPS