$\rho$-meson properties at finite nuclear density

Abstract

We calculate the momentum dependence of the $\rho$-meson selfenergy based on the dispersion relation for the $\rho N$ scattering amplitude $f(\omega$) at low nuclear density. The imaginary part of $f(\omega )$ is determined from the optical theorem, while the total $\rho N$ cross section is obtained within the VDM at high energy and within the resonance model at low energy. Our numerical results indicate a sizeable broadening of the $\rho$-meson width in the medium especially for low relative momenta $p$ while the real part of the $\rho$ selfenergy is found to change its sign and becomes repulsive already at momenta above 100 MeV/c. Extrapolating to nuclear saturation density ${\rho }_0$ we find a dropping of the $\rho$-mass for $p\approx$ 0 in line with the QCD sumrule analysis of Hatsuda while at high energy an increase of the $\rho$-mass in line with the prediction by Eletsky and Joffe is obtained. However, when including a broadening of the baryonic resonances in the medium, the $\rho$-meson mass shift at $p\approx$ 0 becomes slightly repulsive whereas the width increases substantially.

20 pages, LaTeX, including 7 ps-figures, UGI-97-4, revised version, to be pub. in Phys. Rev. C

References in corpus (7)

• Rho Meson Propagation and Dilepton Enhancement in Hot Hadronic Matter
• The Spectral Function of the Rho Meson in Nuclear Matter
• What QCD sum rules tell about the rho meson
• P-Wave Polarization of the $\rho$-Meson and the Dilepton Spectrum in Dense Matter
• Medium effects in the production and decay of vector mesons in pion-nucleus reactions
• Medium effects in the production and decay of $\omega$- and $\rho$-resonances in pion-nucleus interactions
• Resonance Production on Nuclei at High Energies: Nuclear-Medium Effects and Space-Time Picture

Cited by in corpus (34)

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• Shadowing in the nuclear photoabsorption above the resonance region
• Self-consistent description of vector-mesons in matter
• $e^{+}{e}^{-}$ pairs from ${\pi }^{-}$A reactions
• Hadrons in the Nuclear Medium
• $e^{+}{e}^{-}$ production in $pA$ reactions at SIS energies
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• Studying the $\omega$ properties in pA collisions via the $\omega \to {\pi }^0\gamma$ decay
• Low energy onset of nuclear shadowing in photoabsorption
• Nuclear shadowing at low photon energies
• ${\pi }^{+}{\pi }^{-}$ Emission from Coherent ${\rho }^0$ Propagation in Nuclei
• Broadening of $\rho (\to e^{+}{e}^{-})$ meson produced coherently in the photonuclear reaction
• Dilepton production in elementary and in heavy ion reactions
• Reappraisal of rho meson in nuclear matter by inverse QCD sum rules method
• Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in Coherent Photo- and Electroproduction: Coupled Channel Analysis
• $\rho$ meson broadening and dilepton production in heavy ion collisions
• Medium effects on the electromagnetic form factors of the $\rho$ meson
• Shadowing in the low energy photonuclear reaction
• Semihadronic and hadronic decays of ${\rho }^0$ and $\omega$ mesons coherently photoproduced in the isoscalar nuclei
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• Shadowing in photo-production : role of in-medium hadrons
• Nuclear effects on the $\rho$ meson produced in the inclusive photonuclear reaction
• Effect of in-medium parameters of rho meson in its photoproduction reactions on nuclei
• Pion exchange interaction in the $\gamma p\to p{e}^{+}{e}^{-}$ reaction
• Transport analysis of in-medium hadron effects in pA and AA collisions
• Role of in-medium hadrons in photon-nucleus reactions : shadowing and dilepton spectrum
• Dilepton production at SIS energies
• $\rho N$ resonance dynamics in the proton nucleus reaction