Hadrons in Nuclei: Experiments and Perspectives

Abstract

The question of the origin of hadron masses is one major issue in the understanding of the strong interaction. The challenge is addressed by searching for indications of in-medium modifications of hadron properties and studying hadrons in nuclei. The quest driving in-medium studies is to understand the origin of hadron masses in the context of spontaneous chiral symmetry breaking. The experimental status of the modification of hadron properties in the nuclear medium is discussed including experiments using hadron, heavy-ion, and photon beams. Particular emphasis is put on the production of light mesons from nuclei. A number of experimental programs is underway to provide a detailed comparison of properties of free hadrons and hadrons embedded in nuclei. The existing experimental efforts are discussed and possibilities are introduced for the new WASA-at-COSY facility, initially focussed on investigations of symmetries and symmetry breaking, to contribute to the field.

To appear in the proceedings of 23rd International Nuclear Physics Conference (INPC 2007), Tokyo, Japan, 3-8 Jun 2007

References in corpus (29)

• The Cosmological Parameters 2006
• Big-Bang nucleosynthesis (Particle Data Group mini-review)
• Mass and width of the lowest resonance in QCD
• First observation of in-medium modifications of the omega meson
• Experimental Signature of Medium Modifications for rho and omega Mesons in the 12 GeV p + A Reactions
• Study of Non-Strange Baryon Resonances with Meson Photoproduction
• phi photo-production from Li, C, Al, and Cu nuclei at Egamma=1.5 - 2.4 GeV
• Enhanced Production of Low-Mass Electron Pairs in 40 AGeV Pb-Au Collisions at the CERN SPS
• A Precursor of Chiral Symmetry Restoration in the Nuclear Medium
• Photoproduction of eta mesons off protons for photon energies from 0.75 GeV to 3 GeV
• Hadronic Spectral Functions in Nuclear Matter
• Differential cross section measurement of eta photoproduction on the proton from threshold to 1100 MeV
• In-medium modifications of the $\pi \pi$ interaction in photon-induced reactions
• Neutral pion photoproduction off protons in the energy range 0.3 GeV < E(gamma) < 3 GeV
• Photoproduction of pi0-mesons from nuclei
• The $\sigma$ meson in a nuclear medium through two pion photoproduction
• Chiral nonperturvative approach to the isoscalar s-wave pion-pion interaction in a nuclear medium
• The $\pi \pi$ interaction in nuclear matter from a study of the ${\pi }^{+}A\to {\pi }^{+}{\pi }^{\pm }{A}^{\prime }$ reactions
• Double ${\pi }^0$ Photoproduction off the Proton at Threshold
• Studying the $\omega$-mass in-medium in $\gamma +A\to {\pi }^0\gamma +X$ reactions
• Low-energy pions in nuclear matter and 2pi photoproduction within a BUU transport model
• Double pion photoproduction off 40Ca
• Photoproduction of $\eta$-mesons off C and Cu nuclei for photon energies below 1.1 GeV
• The pi -> pi pi process in nuclei and the restoration of chiral symmetry
• General properties of the pion production reaction in nuclear matter
• Two-pion production processes, chiral symmetry and NN interaction in the medium
• Studying the $\omega$ properties in pA collisions via the $\omega \to {\pi }^0\gamma$ decay
• Single Boson Images Via an Extended Holstein Primakoff Mapping
• In-Medium Properties of Hadrons