Hierarchies of Matter matter general features constituents observed
Hierarchies of Matter matter general features: constituents observed as free particles crystal atomic nucleus (macroscopic) 10 -9 m nucleon 10 -10 m nucleon: constituents (quarks) not observed as free particles quarks 10 -14 m • confinement • hadron masses 10 -15 m < 10 -18 m
Hadron Physics • How are hadrons (baryons and mesons) built from quarks and gluons ? e. g. , nucleon mass ? • Can we quantitatively account for the confinement of quarks and gluons inside hadrons ?
Physics program at the HESR • J/ spectroscopy confinement • glueballs (ggg) and hybrids (ccg) • hidden and open charm mesons in nuclei • hypernuclei Further possibilities: • Inverted Deeply Virtual Compton Scattering • CP-violation (D/ -sector) • fundamental symmetries; p in traps
The GSI p - Facility p production with 29 Ge. V p-beam p production rate: 107/s p-stored in the HESR: (High Energy Storage Ring) p-momentum: 1. 5 - 15 Ge. V/c Nstored: 5 • 1010 p High luminosity mode L 2 • 1032 cm-2 s-1 p/p 10 -4 (stochastic cooling) High resolution mode L 1031 cm-2 s-1 p/p 10 -5 (e–- cooling)
Quantumelectrodynamics (QED) Quantumchromodynamics (QCD) Positronium (e+e–) Masse / Me. V binding energy me. V 0 1 S -1000 1 S Charmonium ( c c ) ionisation energy 3900 0 0 3 S 1 1 P 1 3 P 2 3 P 1 3 P 0 a in cog 3 P 2(~3940) 3 P 1(~3880) 1 D 2 0(~3800) 3 P nita 3700 -3000 3500 -5000 3300 1 S -7000 4100 terr 3 S 1 0 Positronium 0. 1 nm 3100 2900 1 fm Charmonium confinement potential 3 D 2
comparison e+e¯ versus pp e+e- interactions: only 1 -- states formed other states populated in secondary decays (moderate mass resolution) Crystall Ball production of 1, 2 E 760 (Fermilab) pp reactions: formation of 1, 2 all states directly formed (very good mass resolution) sm (beam) = 0. 5 Me. V
Glueballs characteristic feature of QCD self -interaction among gluons predicted masses: 1. 5 - 5. 0 Ge. V/c 2 candidate: f 0(1500): 0++; =110 Me. V no flavour blind decay mixing with neighbouring scalar meson states search for higher lying glueball states mixing with (qq) and (QQ) excluded for exotic states mixing with (QQ) small width 100 Me. V
charmed hybrids (ccg) predicted masses: 3. 9 - 4. 5 Ge. V/c 2 lowest state: JPC = 1–+ (exotic) width: could be narrow (LGT: 10 Me. V) forbidden decays: e. g. O+– DD, D*D*, DSDS (CP-violation) (QQg) (Qq)L=0 + (Qq)L=0 (dynamic selection rule) below 4. 3 Ge. V/c 2 no decay into DD preferred decays: (ccg) (cc) + X e. g. 1+– J/ + , ,
in-medium modification of mesons study of chiral symmetry restoration in the charm sector
Open Charm in Nuclei Consequence of dropping Dmeson mass in the medium: strong enhancement of D-meson cross section in near/sub-threshold region probing D-meson properties at ground state nuclear matter density and T 0 (complementary to heavy ion collisions)
J/ - nucleon interaction • J/ - suppression regarded as signature for the generation of the quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions • suppression due to purely hadronic interactions? measure N-J/ cross section in nuclear matter
Strangesess three-dimensional nuclear chart with strangeness degree of freedom Neutron Number
Double Hypernucleus Spectroscopy double hypernuclens production ¯(dss) p(uud) (uds) detector scheme rates: applying K-trigger: 3 • 105 stopped ¯ / d detected -transitions: 100 / d ke. V-resolution !!
layout of proposed new GSI facility p-beam
synergy effect: parallel operation of physics programs
Conclusion • The interaction of cooled antiproton beams with nucleons and nuclei opens up a broad and challenging research program ranging from non-perturbative QCD – phenomena (glueballs, hybrids, confinement, chiral symmetry breaking) to CP-violation and tests of fundamental symmetries. • High luminosity and monochromaticity at HESR will provide high precision data and sensitivity to rare processes. • Electron-cooling in the HESR is a technological challenge. • With the realisation of the HESR as integral part of the future accelerator facility, GSI will play a pioneering role in the experimental exploration of long-distance (non-perturbative) QCD and the structure of hadronic matter.
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