hierarchies of matter
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Hierarchies of MatterHierarchies of Matter
matter
crystal
atom
atomic nucleus
nucleon
quarks
10-9 m
10-10 m
10-14 m
10-15 m
< 10-18 m
(macroscopic)
• confinement
• hadron masses
general features: constituents observed as
free particles
ii
m m
nucleon: constituents (quarks) not observed as free particles
ii
m m
Hadron PhysicsHadron Physics
• How are hadrons (baryons and mesons) built from quarks and gluons ?
• Can we quantitatively account for the confinement of quarks and gluons inside hadrons ?
e.g., nucleon mass ?
• J/ spectroscopy confinement
• glueballs (ggg) and hybrids (ccg)
• hidden and open charm mesons in nuclei
• hypernuclei
Physics program at the HESRPhysics program at the HESR
Further possibilities:
• Inverted Deeply Virtual Compton Scattering
• CP-violation (D/-sector)
• fundamental symmetries; p in traps
The GSI p - FacilityThe GSI p - Facility
p production with 29 GeV p-beam p production rate: 107/s
p-stored in the HESR: (High Energy Storage Ring) p-momentum: 1.5 - 15 GeV/c
Nstored: 5 • 1010 pHigh luminosity mode L 2 • 1032 cm-2s-1 p/p 10-4 (stochastic cooling)High resolution mode
L 1031 cm-2s-1 p/p 10-5 (e–- cooling)
Quantumelectrodynamics (QED)Quantumelectrodynamics (QED) Quantumchromodynamics (QCD)Quantumchromodynamics (QCD)
r
crV
rV
r
rKr
c
3
4rV S
rforrV
confinement potential
rV
Masse / MeV
2900
3100
3300
3500
3700
3900
4100
3730DD
)3097(
)3686(')3770(''
)4040('''
)3525(hc )3510(1)3556(2
)3415(0
)3590('c
)2980(c
1D23D2
3P0(~3800)3P1(~3880)
3P2(~3940)
terra incognita
cc
Charmonium
1fm
Charmonium ( c c )Positronium (e+e–)
ionisation energy
binding energy meV
0
-1000
-3000
-5000
-7000
e e
Positronium
0.1nm1S0
1S0
1S0
3S1
3S11P1 3P1
3P0
3P2
comparison e+e¯ versus ppcomparison e+e¯ versus pp
e+e- interactions: only 1-- states formed other states populated in secondary decays (moderate mass resolution)
pp reactions: all states directly formed (very good mass resolution)
production of 1,2
'ee
2,1
/J ee
formation of 1,2
/J ee
2,1pp
Crystall Ball
E 760 (Fermilab)
m (beam) = 0.5 MeV
GlueballsGlueballs
characteristic feature of QCD self-interaction among gluons
predicted masses: 1.5 - 5.0 GeV/c2
candidate: f0(1500): 0++; =110MeV 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 MeV
charmed hybrids (ccg)charmed hybrids (ccg)
predicted masses: 3.9 - 4.5 GeV/c2
lowest state: JPC = 1–+ (exotic)
width: could be narrow (LGT: 10 MeV)
forbidden decays:
e.g. O+– DD, D*D*, DSDS (CP-violation)(QQg) (Qq)L=0 + (Qq)L=0 (dynamic selection rule)
below 4.3 GeV/c2 no decay into DD
preferred decays:
(ccg) (cc) + X
e.g. 1+– J/ + , ,
in-medium modification of mesons
in-medium modification of mesons study of chiral symmetry
restoration in the charm sector
Open Charm in NucleiOpen Charm in Nuclei
Consequence of dropping D-meson 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 interactionJ/ - 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
)1A(/JAp
Str
ange
sess
Neutron Number
three-dimensional nuclear chart with strangeness degree of freedomthree-dimensional nuclear chart
with strangeness degree of freedom
Double Hypernucleus SpectroscopyDouble Hypernucleus Spectroscopy
double hypernuclens productiondouble hypernuclens production detector schemedetector scheme
¯(dss) p(uud) (uds) (uds) rates: applying K-trigger: 3 • 105 stopped ¯ / d
detected -transitions: 100 / d
keV-resolution !!
layout of proposed new GSI facilitylayout of proposed new GSI facilityp-beam
p-beam
synergy effect: parallel operation of physics programssynergy effect: parallel operation of physics programs
ConclusionConclusion
• 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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