Observation of $\rho /\omega$ Meson Modification in Nuclear Matter

Abstract

We have measured invariant mass spectra of electron-positron pairs in the target rapidity region of 12GeV p+A reactions. We have observed a significant difference in the mass spectra below the $\omega$ meson between p+C and p+Cu interactions. The difference is interpreted as a signature of the $\rho /\omega$ modification at normal nuclear-matter density.

8 pages, 3 figures, submitted to Phys. Rev. Letters. all the figures changed to Postscript format, text not changed

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Cited by in corpus (57)

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• Behavior of Hadrons at Finite Density -- Lattice Study of Color SU(2) QCD
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• Phi-meson photoproduction from nuclei
• In-medium hadronic spectral functions through the soft-wall holographic model of QCD
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• The spectral function of the omega meson in nuclear matter from a coupled-channel resonance model
• Dropping rho and A_1 Meson Masses at Chiral Phase Transition in the Generalized Hidden Local Symmetry
• Dilepton production in heavy-ion collisions with in-medium spectral functions of vector mesons
• Nuclear-matter modification of decay widths in the $\varphi \to e^{+}{e}^{-}$ and $\varphi \to K^{+}{K}^{-}$ channels
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• Dilepton Radiation from Strongly Interacting Systems
• In-Medium rho^0 Spectral Function Study via the 2H, 3He, 12C(gamma,pi+pi-) Reaction
• How Sensitive are Di-Leptons from Rho Mesons to the High Baryon Density Region?
• Nuclear mass number dependence of inclusive production of omega and phi mesons in 12 GeV p + A collisions
• Study of possible ωbound states in nuclei with the (γ,p) reaction
• Analysis of Dilepton Invariant Mass Spectrum in C+C at 2 and 1 AGeV
• Thermal Radiation from Au + Au Collisions at \sqrt{s} = 200 GEV/A Energy
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• Simultaneous Softening of sigma and rho Mesons associated with Chiral Restoration
• Binding energy per nucleon and hadron properties in nuclear matter
• Weighted finite energy sum rules for the omega meson in nuclear matter
• Electromagnetic Probes
• Renormalization group equations in a model of generalized hidden local symmetry and restoration of chiral symmetry
• $\omega N$ scattering length from $\omega$ photoproduction on the proton near the threshold
• Open questions in quarkonium and electromagnetic probes
• $e^{+}{e}^{-}$ production in $pA$ reactions at SIS energies
• The width of the omega meson in the nuclear medium
• $\rho /\omega$ properties from dilepton spectra in $pA$ reactions at 12 GeV
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• A novel spectral broadening from vector--axial-vector mixing in dense matter
• Spectral Red-Shift Versus Broadening from Photon and Dilepton Spectra
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• Analysis of $\omega$ self-energy at finite temperature and density in the real-time formalism
• Low-mass dielectrons from the PHENIX experiment at RHIC
• Brown-Rho Scaling in the Strong Coupling Lattice QCD
• Dilepton production in elementary and in heavy ion reactions
• Probing dense and hot matter with low-mass dileptons and photons
• Effects of Meson Mass Reduction on the Properties of Neutron Star Matter
• Medium effects on the electromagnetic form factors of the $\rho$ meson
• Dielectron Production in Heavy Ion Collisions at 158 GeV/c per Nucleon
• Hadron Masses in Medium and Neutron Star Properties
• Effective mass and decay of ${\Theta }^{+}$ in nuclear matter in quark-meson coupling model
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• Helicity Signatures in Subthreshold rho Production on Nuclei
• Forward coherent $\omega$ and $\varphi$ mesons production in the photon induced reaction on nuclei
• Role of in-medium hadrons in photon-nucleus reactions : shadowing and dilepton spectrum
• Selfconsistent descriptions of vector-mesons in hot matter revisited