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High Energy Storage Ring HESR. p. P max = 15 GeV/c L max = 2 ·10 32 cm -2 s -1 Ø < 100 μm Δ p/p < 10 -5. e - cooler. detector. Experiments with a cooled p beam on an internal target. Physics program Detector set-up. Carsten Schwarz. Glueballs Hybrids. Physics program.
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High Energy Storage Ring HESR p Pmax = 15 GeV/c Lmax = 2·1032 cm-2 s-1 Ø < 100 μm Δ p/p < 10-5 e- cooler detector Experiments with a cooled p beam on an internal target • Physics program • Detector set-up Carsten Schwarz
Glueballs Hybrids Physics program Charmonium spectroscopy Medium modifications of D mesons and J/Ψ in nuclei Hypernuclei CP violation
Mass modifications of mesons pionic atoms π- 25 MeV π π+ KAOS/FOPI K+ K 100 MeV K- HESR D D- 50 MeV ? D+ vacuum nuclear medium ρ = ρ0 Medium modifications of D mesons and J/Ψ in nuclei Continuation of present GSI physics FOPI, KAOS, HADES, …HESR Signal: medium modification of production threshold, resonance width e.g. Ψ’, χ2 Absorption cross section of J/Ψ in nuclei (ρ=ρ0).
Charmonium spectroscopy • Charmonium gives information about QCD confinement potential. • Many states are still missing. • pp: direct population of all states. • HESR allows investigation of states above DD threshold. • Cooled beams with Δp/p≤10-5 allow high precision scan of resonances. Crystal Ball e+e- 40 keV
_ X 3 GeV/c p X- Hypernuclei K+K Trigger • X-(dss)p(uud)L(uds)L(uds) • study of L L interaction secondary target
Signal: exotic quantum numbers: partial wave analysis normal quantum numbers: model comparison (LGT) Glueballs Hybrids mixing with normal mesons charm sector: few resonances with small widths Meson Hybrid Glueball ggg qq qqg Normal meson: 2 fermions P = (-1)L+1 C = (-1)L+S Excited glue: bosonic degree of freedom → exotic quantum numbers eg. JPC=1-+, 0--, 0+-, 2+-… → normal quantum numbers
Measure decay asymmetry of angular distribution of p relative to Λ-Hyperon momentum. Ip(θp) ~ 1+α cos(θp) for Λ Ip(θp) ~ 1+α cos(θp) for Λ CP conservation: α = - α Signal for CP violation: Theoretical prediction: ~10-4 ~ 10-5 Experiment: 1010 reconstructed ΛΛ L=2·1032 cm-2 s-1 → >1 year running p + p → Λ +Λ ↓ ↓ pπ- pπ+ CP violation in Hyperon decay
HESR-Detector Simulations with Pluto event generator Formation of Ψ’and decay in myons electrons similar → calorimeter for large angles. Ψ’→μ+μ- Ψ’→J/Ψ + X ↓ μ+μ-
HESR-detector target spectrometer forward spectrometer Internal target top view Heavy charmed mesons decay in light products with large pt. Solenoid is important.
side view HESR detector
Collaborations: Working group: LEAR, COSY, SATURNE community Munich Germany Bochum “ Giessen “ Dresden “ Erlangen “ Jülich “ Ferrara Italy Turin “ Krakow Poland Warsaw “ T. Barnes D. Bettoni R. Calabrese M. Düren S. Ganzhur V. Hejny H. Koch U. Lynen V. Metag H. Orth S. Paul K. Peters J. Pochodzalla J. Ritman L. Schmitt C. Schwarz K. Seth W. Weise U. Wiedner