{rho}-{omega} mixing in asymmetric nuclear matter via a QCD sum rule approach

Journal Article · Mon Jan 01 04:00:00 EST 2001 · Physical Review C

DOI:https://doi.org/10.1103/PhysRevC.63.015204· OSTI ID:40206124

Dutt-Mazumder, Abhee K; Hofmann, Ralf; Pospelov, Maxim

We evaluate the operator product expansion (OPE) for a mixed correlator of the isovector and isoscalar vector currents in the background of the nucleon density with intrinsic isospin asymmetry (i.e., excess of neutrons over protons) and match it with its imaginary part, given by resonances and continuum, via the dispersion relation. The leading density-dependent contribution to {rho}-{omega} mixing is due to the scattering term, which turns out to be larger than any density dependent piece in the OPE. We estimate that the asymmetric density of n{sub n}-n{sub p}{approx}2.5x10{sup -2}fm{sup -3} induces the amplitude of {rho}-{omega} mixing, equal in magnitude to the mixing amplitude in vacuum, with the constructive interference for positive and destructive for negative values of n{sub n}-n{sub p}. We revisit sum rules for vector meson masses at finite nucleon density to point out the numerical importance of the screening term in the isoscalar channel, which turns out to be one order of magnitude larger than any density-dependent condensates over the Borel window. This changes the conclusions about the density dependence of m{sub {omega}}, indicating {approx}40MeV increase at nuclear saturation density.

• Sponsoring Organization: (US)
• OSTI ID: 40206124
• Journal Information: Physical Review C, Journal Name: Physical Review C Journal Issue: 1 Vol. 63; ISSN 0556-2813
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
DISPERSION RELATIONS
NUCLEAR MATTER
NUCLEONS
OPERATOR PRODUCT EXPANSION
QUANTUM CHROMODYNAMICS
SUM RULES
VECTOR CURRENTS
VECTOR MESONS