Transverse-momentum distribution of dileptons in different scenarios for the QCD phase transition

Journal Article · Wed Apr 01 04:00:00 EST 1987 · Phys. Rev. D; (United States)

DOI:https://doi.org/10.1103/PhysRevD.35.2153· OSTI ID:5975819

Cleymans, J; Fingberg, J; Redlich, K

The transverse-momentum distribution of lepton pairs produced in ultrarelativistic nuclear collisions is analyzed in different scenarios for the phase transition from quarks and gluons to hadrons. A first-order phase transition at equilibrium is characterized by an intermediate phase where quarks, gluons, and hadrons coexist for an appreciable amount of proper time. The subsequent transition from one phase to the other is therefore very smooth. This is reflected in the dilepton production rate by a smooth change from the small- to the large-dilepton-invariant-mass region. A detonation is characterized by substantial supercooling of the quark-gluon-plasma phase with a subsequent superheating of the hadronic phase. The superheating is so intense that the dilepton rate arises almost completely from the hadronic phase, leaving almost no trace from the quark-gluon phase. A second-order phase transition is characterized by an instantaneous transition from one phase to the other. This reflects itself in a clean separation in the invariant mass in the dilepton production rate. It is suggested that experimental measurement of the average transverse momentum as a function of the invariant mass might help considerably in determining the dilepton production mechanism and through it reveal part of the evolution of the quark-gluon-plasma phase to the hadronic phase.

• Research Organization: Fakultat fuer Physik, Universitat Bielefeld, Federal Republic of Germany
• OSTI ID: 5975819
• Journal Information: Phys. Rev. D; (United States), Journal Name: Phys. Rev. D; (United States) Vol. 35:7; ISSN PRVDA
• Country of Publication: United States
• Language: English

Related Subjects

653003* -- Nuclear Theory-- Nuclear Reactions & Scattering
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BAG MODEL
COMPOSITE MODELS
ELEMENTARY PARTICLES
ENERGY DENSITY
ENERGY RANGE
ENTROPY
EQUATIONS
EQUATIONS OF STATE
EXTENDED PARTICLE MODEL
FERMIONS
FIELD THEORIES
HADRON-HADRON INTERACTIONS
HEATING
INTERACTIONS
LEPTONS
LINEAR MOMENTUM
MATHEMATICAL MODELS
MATTER
NUCLEAR SUPERHEATING
PAIR PRODUCTION
PARTICLE INTERACTIONS
PARTICLE MODELS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MATTER
QUARK MODEL
RELATIVISTIC RANGE
SPACE-TIME
SUPERHEATING
THERMODYNAMIC PROPERTIES
TRANSVERSE MOMENTUM