Hadrons in strongly interacting matter

Abstract

We review the current status of theories and experiments aiming at an understanding and a determination of the properties of light vector and scalar mesons inside strongly interacting hadronic matter. Starting from a discussion of the relevant symmetries of QCD and their connection with the hadronic description through QCD sum rules we then discuss hadronic models used to calculate the in-medium self-energies of hadrons and their spectral functions. The difficulties to link these calculated properties to actual observables are emphasized. Finally, we review in detail all the running experiments searching for in-medium changes of vector and scalar mesons, both with relativistic heavy-ion reactions as well as with elementary reactions on (cold) nuclei. Inconsistencies among experimental results are discussed. While almost all experiments observe a considerable broadening of vector mesons inside the nuclear medium, no evidence for mass changes is observed in the majority of the experiments.

Review, revised version, to appear in Int. J. Mod. Phys. E

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Cited by in corpus (113)

• Transport-theoretical Description of Nuclear Reactions
• Heavy Hadrons in Nuclear Matter
• Experimental evidence for an attractive p-$\varphi$ interaction
• Recent Progress in QCD Condensate Evaluations and Sum Rules
• Meson-nucleus potentials and the search for meson-nucleus bound states
• Dielectron production in Ar+KCl collisions at 1.76A GeV
• Nuclear-bound quarkonia and heavy-flavor hadrons
• Absorption of the $\omega$ and $\varphi$ Mesons in Nuclei
• Thermal Dileptons from Coarse-Grained Transport as Fireball Probes at SIS Energies
• Interaction of vector mesons with baryons and nuclei
• Measurement of the in-medium phi-meson width in proton-nucleus collisions
• Dilepton production in proton-induced reactions at SIS energies with the GiBUU transport model
• Dilepton production and reaction dynamics in heavy-ion collisions at SIS energies from coarse-grained transport simulations
• Inclusive dielectron spectra in p+p collisions at 3.5 GeV
• Constraining the strangeness content of the nucleon by measuring the $\varphi$ meson mass shift in nuclear matter
• Baryon and meson screening masses
• Measurement of excitation spectra in the ${}^{12}$C$(p,d)$ reaction near the ${\eta }^{\prime }$ emission threshold
• $J/\Psi$-nuclear bound states
• Photoproduction of mesons off nuclei
• First measurement of low momentum dielectrons radiated off cold nuclear matter
• Dilepton production and resonance properties within a new hadronic transport approach in the context of the GSI-HADES experimental data
• Moments of $\varphi$ meson spectral functions in vacuum and nuclear matter
• In-medium $\omega$ mass from the $\gamma +Nb\to {\pi }^0\gamma +X$ reaction
• D meson mass increase by restoration of chiral symmetry in nuclear matter
• Momentum dependence of the phi-meson nuclear transparency
• A coarse-graining approach for dilepton production at SPS energies
• Phi meson spectral moments and QCD condensates in nuclear matter
• $\varphi$ meson mass and decay width in nuclear matter and nuclei
• Baryon resonance production and dielectron decays in proton-proton collisions at 3.5 GeV
• Momentum dependence of the imaginary part of the $\omega$- and ${\eta }^{\prime }$-nucleus optical potential
• Missing-mass spectroscopy of the ${}^{12}\mathrm{C}(p,d)$ reaction near the ${\eta }^{\prime }$-meson production threshold
• $\Phi$-meson--nucleus bound states
• ${\bar{K}}^{\ast }$ meson in dense matter
• Photon and dilepton production at the Facility for Antiproton and Ion Research and the beam energy scan program at the Relativistic Heavy-Ion Collider using coarse-grained microscopic transport simulations
• Medium effects in proton-induced $K^0$ production at 3.5 GeV
• Inclusive dielectron production in proton-proton collisions at 2.2 GeV beam energy
• Study of the quasi-free $np\to np{\pi }^{+}{\pi }^{-}$ reaction with a deuterium beam at 1.25 GeV/nucleon
• Search for Quasi Bound $\eta$ Mesons
• Electroweak properties of pions in a nuclear medium
• Dilepton Radiation from Strongly Interacting Systems
• QCD Sum Rule for Open Strange Meson $K_1^{\pm }$ in Nuclear Matter
• $J/\psi$ reaction mechanisms and suppression in the nuclear medium
• Parity doubling of baryons in a chiral approach with three flavors
• Quarks and light (pseudo-)scalar mesons at finite chemical potential
• Investigating in-medium properties of the $\omega$ meson via the $\omega \to {\pi }^0\gamma$ decay
• The mass of heavy-light mesons in a constituent quark picture with partially restored chiral symmetry
• The η'-carbon potential at low meson momenta
• The rho meson in a scenario of pure chiral restoration
• Photoproduction of $\omega$ mesons on nuclei near the production threshold
• Experimental approaches for determining in-medium properties of hadrons from photo-nuclear reactions
• In-Medium Modifications of Scalar Charm Mesons in Nuclear Matter
• General structure of the neutral $\rho$ meson self-energy and its spectral properties in a hot and dense magnetized medium
• ${\eta }_c$-nucleus bound states
• $\varphi$ meson mass and decay width in strange hadronic matter
• A novel probe of chiral restoration in nuclear medium
• Flavor Dependence of Meson Melting Temperature in Relativistic Potential Model
• The masses of hadrons in the chiral symmetry restored vacuum
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• Mean Field Effect on J/ψProduction in Heavy Ion Collisions
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• Light vector correlator in medium: Wilson coefficients up to dimension 6 operators
• Medium Modifications of the Rho Meson in Nuclear Photoproduction
• The width of the omega meson in the nuclear medium
• Masses and decay constants of (axial-)vector mesons at finite chemical potential
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• Momentum dependence of pion-induced $\varphi$ meson production on nuclei near threshold
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• Effective spectral function of vector mesons via lifetime analysis
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• Analysis of $\omega$ self-energy at finite temperature and density in the real-time formalism
• Low energy ω(\to π^0 γ) meson photoproduction in the nucleus
• Dilepton production at SIS energies with the GiBUU transport model
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• Theory on Hadrons in Nuclear Medium
• Hadrons in Medium
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• Mesons in Nuclei: eta and omega mesons
• Hadron modification in a dense baryonic matter
• $\Phi$ and $J/\Psi$ Mesons in Cold Nuclear Matter
• $K_1^{\pm }$ mesons moving in nuclear matter
• Dilepton Production in Transport-based Approaches
• Vector Meson Spectral Functions in a Coarse-Graining Approach
• Towards an effective field theory for vector mesons
• Strange meson production at high density and temperature
• Selected topics on Hadrons in Nuclei
• ${\bar{K}}^{\ast }$ meson in nuclear matter
• Chiral symmetry, di-electrons and charm
• Selfconsistent descriptions of vector-mesons in hot matter revisited
• Dileptons, Charm and Charmonium at Finite Temperature and Chemical Potential
• Direct measurement of the in-medium ${\eta }^{\prime }$ mass spectrum through the $\gamma \gamma$ decay channel
• Nuclear medium effects on the ${\bar{K}}^{\ast }$ meson
• Lifetime of the eta' meson at low temperature