Heating (gapless) color-flavor locked quark matter

Journal Article · Tue Feb 01 04:00:00 EST 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.71.034002· OSTI ID:20705920

Fukushima, Kenji; Kouvaris, Chris; Rajagopal, Krishna ^[1]

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1. Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

We explore the phase diagram of neutral quark matter at high baryon density as a function of the temperature T and the strange quark mass M{sub s}. At T=0, there is a sharp distinction between the insulating color-flavor locked (CFL) phase, which occurs where M{sub s}{sup 2}/{mu}<2{delta}, and the metallic gapless CFL phase, which occurs at larger M{sub s}{sup 2}/{mu}. Here, {mu} is the chemical potential for quark number and {delta} is the gap in the CFL phase. We find this distinction blurred at T{ne}0, as the CFL phase undergoes an insulator to metal crossover when it is heated. We present an analytic treatment of this crossover. At higher temperatures, we map out the phase transition lines at which the gap parameters {delta}{sub 1}, {delta}{sub 2}, and {delta}{sub 3} describing ds pairing, us pairing and ud pairing, respectively, go to zero in an Nambu-Jona-Lasinio (NJL) model. For small values of M{sub s}{sup 2}/{mu}, we find that {delta}{sub 2} vanishes first, then {delta}{sub 1}, then {delta}{sub 3}. We find agreement with a previous Ginzburg-Landau analysis of the form of these transitions and find quantitative agreement with results obtained in full QCD at asymptotic density for ratios of coefficients in the Ginzburg-Landau potential. At larger M{sub s}{sup 2}/{mu}, we find that {delta}{sub 1} vanishes first, then {delta}{sub 2}, then {delta}{sub 3}. Hence, we find a ''doubly critical'' point in the (M{sub s}{sup 2}/{mu},T) plane at which two lines of second order phase transitions ({delta}{sub 1}{yields}0 and {delta}{sub 2}{yields}0) cross. Because we do not make any small-M{sub s} approximation, if we choose a relatively strong coupling leading to large gap parameters, we are able to pursue the analysis of the phase diagram all the way up to such large values of M{sub s} that there are no strange quarks present.

• OSTI ID: 20705920
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 3 Vol. 71; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
COLOR MODEL
FLAVOR MODEL
GINZBURG-LANDAU THEORY
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
POTENTIALS
QUANTUM CHROMODYNAMICS
QUARK MATTER
S QUARKS
STRONG-COUPLING MODEL