1. Hadron Physics @
Klaus Peters Ruhr-Universität Bochum Santiago de Campostela, Oct 27, 2003

2. The Panda Physics Program
Overview
The Panda Physics Program
Charmonium spectroscopy
Charmed hybrids and glueballs
Interaction of charmed particles with nuclei
(Double) Hypernuclei
Many further options
Detector Concepts for Panda
Conclusions
K. Peters - Hadron Panda

3. QCD running coupling constant
transition from perturbative to non-perturbative regime
Q2 [GeV2] 10 1
0.1
0.05
perturbative QCD
constituent quark
confinement
mesons and baryons
0.3 Rn
r [fm]
perturbative
strong
QCD
Transition from the quark-gluon to the hadronic degrees of freedom
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4. Objects of Interest
SU(3)C Symmetry tells us that q3i+nq3j+ngk is color neutral
i=1 j,n,k=0 baryon (B=i-j) i,j,k=0 n=1 meson i,j,n=0 k>1 glueball i,j=0 n=1 k>0 meson hybrid i=1 j,n=0 k>0 baryon hybrid i,n=1 j,k=0 penta quark i,j,k=0 n=2 four quark i,j,k=0 n=3 / i,j=3 k,n=0 baryonium (hexa quark)
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5. Objects of Interest Mesons/Baryons Molecules/Multiquarks Hybrids
AntiQuark
Mesons/Baryons
Molecules/Multiquarks
Hybrids
Glueballs
+ Effects due to the complicated QCD vacuum
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6. Light Meson Spectrum Lattice 1-+ 1.9 GeV 0++ 1.6 GeV exotic nonets
qq Mesons
Each box corresponds
to 4 nonets (2 for L=0)
Radial
excitations
2–+
2.5
0–+
Hybrids
2++
2+–
2–+
1––
2.0
1–+
exotic
nonets
Glueballs
1+–
1++
1.5
Lattice
GeV
0+–
0–+
0++
1.0
GeV
L = 0 1 2 3 4
(L = qq angular momentum)
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7. Level Mixing Mixing (Light Quark) Better: Experimental approach:
broad states
high level density
Better:
narrow states and/or
lower level density
charmed systems !
Experimental approach:
Charm physics: Transition
chiral to heavy quark limits
Proton-Antiproton:
rich hadronic source
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8. Charmonium Physics Open questions … … Exclusive Channels
hc – inconsistencies
hc’ - y(2S) splitting
h1c (1P1) unconfirmed
Peculiar decays of y(4040)
Terra incognita for any 2P and D-States
… Exclusive Channels
Helicity violation
G-Parity violation
Higher Fock state contributions
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9. Charmonium Physics e+e- interactions: cc1 pp reactions:
Only 1-- states are formed
Other states only by secondary decays (moderate mass resolution)
pp reactions:
All states directly formed (very good mass resolution)
3500
3520 MeV
3510
CBall ev./2 MeV
100
ECM
CBall
E835
cc1
1000
E 835 ev./pb
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10. Resonance Cross Section
Resonance Scan
ECM
Resonance Cross Section
Measured Rate
Beam Profile
small and well controlled beam momentum spread Dp/p is extremely important
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11. Charmonium Physics with pp
Expect 1-2 fb-1 (like CLEO-C)
pp (>5.5 GeV/c) ® J/y 107/d
pp (>5.5 GeV/c) ® cc2 (® J/y g) 105/d
pp (>5.5 GeV/c) ® hc‘(® ff) 104/d|rec.?
Comparison of to E835
Maximum energy 15 GeV/c instead of 9 GeV/c
Luminosity 10x higher
Detector with magnetic field – charged final states
Dp/p 10x better
Dedicated machine with stable conditions
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12. Charmed Hybrids
Gluonic excitations of the quark-antiquark-potential may lead to bound states
LQCD:
P-potential of excited gluon flux in addition to S-potential for one-gluon exchange
mHc ~ GeV/c2
Light charmed hybrids could be narrow if open charm decays are inaccessible or suppressed P S
important <r2> and rBreakup
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13. S-Wave+Gluon (qq)8g with ()8=coloured 1S0 ­¯ 3S1 ­­
Simplest Hybrids
S-Wave+Gluon (qq)8g with ()8=coloured
1S0 ­¯ 3S1 ­­
combined with a 1+ or 1- gluon
Gluon
1– (TM)
1+(TE)
1S0, 0–+
1++
1––
3S1, 1––
0+-
0–+
1+-
1–+
2+-
2–+
Meson – Hybrid Mixing q
g MIX
g FSI
Exotic JPC cannot! be formed by qq
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14. Charmed Hybrid Level Scheme
1-- (0,1,2)-+ < 1++ (0,1,2)+-
JKM00, NPB83Suppl83(2000)304 and Manke, PRD57(1998)3829
L-Splitting
Dm ~ MeV/c2 for 1-+ to 0+-
S-Splittings
Page thesis,1995 and PRD35(1987)1668
4.14 (0-+ ) to 4.52 GeV/c2 (2-+)
consistent w/LQCD
JKM, NPB86suppl(2000)397, PLB478(2000) 151
4.8
4.7
4.6
4.5
4.4
4.3
DD**
4.2
4.1
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15. Charmed Hybrid Level Scheme
1-- (0,1,2)-+ < 1++ (0,1,2)+-
JKM00, NPB83Suppl83(2000)304 and Manke, PRD57(1998)3829
L-Splitting
Dm ~ MeV/c2 for 1-+ to 0+-
S-Splittings
Page thesis,1995 and PRD35(1987)1668
4.14 (0-+ ) to 4.52 GeV/c2 (2-+)
consistent w/LQCD
JKM, NPB86suppl(2000)397, PLB478(2000) 151
0+-
1+-
2+-
1++
4.8
4.7
4.6
0-+
1-+
2-+
1--
4.5
4.4
4.3
DD**
4.2
4.1
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16. Proton-Antiproton @ Rest/Flight
Production
all JPC available
Formation
only selected JPC
Gluon rich process creates gluonic excitation in a direct way
cc requires the quarks to annihilate (no rearrangement)
yield comparable to charmonium production
formation yield 8:1 due to colour octet in hybrids
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17. Proton-Antiproton @ Rest/Flight
Production p _ G M p M H _ p M H _
all JPC available
Formation p _ G p _ H p _ H
only selected JPC
Gluon rich process creates gluonic excitation in a direct way
cc requires the quarks to annihilate (no rearrangement)
yield comparable to charmonium production
formation yield 8:1 due to colour octet in hybrids
Momentum range for a survey pp ® ~15 GeV
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18. Exotics in Proton-Antiproton
Exotics are heavily produced in pp reactions
High production yields for exotic mesons (or with a large fraction of it)
f0(1500)p ® ~25 % in 3p0
f0(1500)p ® ~25 % in 2hp0
p1(1400)p ® >10 % in p±p0h
Crystal Barrel
Interference with other well
known (conventional) states is
mandatory for the phase analysis
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19. Open charm discoveries
The DS± Spectrum |cs> +c.c. was not expected to reveal any surprises, but chiral and heavy quark aspects meet
Potential model
Old measurements
New observations
m [GeV/c2]
Ds1
Ds2
D*K
DsJ
(2458)
D0K
# 1267  53
Events in peak
DsJ*
(2317)
Ds*
Combinatorial DS*+ g
DS*+(2112)
DsJ*(2317) Ds
BABAR 0- 1- 0+ 1+ 2+ 3- JP
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20. Heavy Glueballs
Light gg/ggg-systems are complicated to identify (mixing!)
Exotic heavy glueballs
m(0+-) = 4140(50)(200) MeV
m(2+-) = 4740(70)(230) MeV
Width unknown, but!
nature invests more likely in mass than in momentum
newest proof: double cc yield in e+e-
Flavour-blindness
predicts decays into charmed final states too
Same run period as hybrids
In addition: scan m>2 GeV/c2
Morningstar und Peardon, PRD60 (1999)
Morningstar und Peardon, PRD56 (1997) 4043
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21. Accessible cc-Hadrons at PANDA @ HESR @ GSI
mass and phase space
of recoil meson for
exotic JPC included
conventional
charmonium
Other exotics with identical decay channels ® same region
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22. Charmed Hadrons in Nuclear Matter
Partial restoration of chiral symmetry in nuclear matter
Light quarks are sensitive to quark condensate
Evidence for mass changes of pions and kaons has been deduced previously:
deeply bound pionic atoms
(anti-)kaon yield and phase space distribution
D-Mesons are the QCD analogue of the H-atom.
chiral symmetry to be studied on a single light quark
vacuum
nuclear medium p K
25 MeV
100 MeV K+ K- p- p+
Hayaski, PLB 487 (2000) 96
Morath, Lee, Weise, priv. Comm. D-
50 MeV D D+
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23. Open Charm in the Nuclei
The expected signal:
strong enhancement of the D-meson cross section,
relative D+ D- yields, in the near/sub-threshold region.
Complementary to
heavy ion collisions
T~0
in-medium
free masses
bare D+D-
10-2
10-1 1 10
102
103
s(nb) 4 5 6 7 D-
spA
spA
(A) = ?
AspN
AspN D+
T (GeV)
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24. Charmonium in the Nuclei
GeV/c2 Mass
Lowering of the D+D- mass
allow charmonium states to decay into this channel,
thus resulting in a dramatic increase of width
y(1D) Γ=20®40 MeV
y(2S) Γ=0,32®2,7 MeV
Experiment:
Dilepton-Channels and/or highly constrained hadronic channels
Idea
Study relative changes of yield and width of the charmonium states.
y(33S1) 4
3.8
y(13D1)
3,74
3,64
3,54
vacuum
1r0
2r0
y(23S1)
3.6
cc2(13P2)
cc1(13P1)
3.4
cc1(13P0)
3.2
y(13S1)
hc(11S0) 3
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25. J/y Absorption in Nuclei
Important for the understanding of heavy ion collisions
Related to QGP p
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26. J/ψ Absorption in Nuclei
Important for the understanding of heavy ion collisions
Related to QGP
Reaction
p + A  J/ψ + (A-1)
Fermi-smeared cc-Production
J/ψ, ψ’ or interference region selected by p-Momentum
Longitudinal und transverse Fermi-distribution is measurable
J/y
s(e+e-) pb
p(pbar) GeV/c
200
100
3.5
4.5
4.0
5.0 FF
J/y
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27. Further Experiments and Optional extensions
Hypernuclear physics
3rd dimension of nuclear chart
Focus: Double Hypernuclei
Inverted DVCS - WACS
Measure dynamics of quarks and gluons in a hadron
Handbag diagram – electromagnetic final states
Proton Formfactors at large Q2
s up to 25 GeV2/c4
D(S)-Physics
Spectroscopy: Threshold production
BR and decay dalitz plots with high statistics
CP-Violation in the D-Sector
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28. The Antiproton Facility
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29. The Antiproton Facility
Antiproton production similar to CERN,
HESR = High Energy Storage Ring
Production rate 107/sec
Pbeam = GeV/c
Nstored = 5 x 1010 p
Gas-Jet/Pellet/Wire Target
High luminosity mode
Luminosity = 2 x 1032 cm-2s-1
Dp/p ~ (stochastic cooling)
High resolution mode
Dp/p ~ (electron cooling)
Luminosity = 1031 cm-2s-1
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30. Proposed Detector (Overview)
High Rates
Total σ ~ 55 mb
Vertexing
(σp,KS,Λ,…)
Charged particle ID
(e±,μ±,π±,p,…)
Magnetic tracking
Elm. Calorimetry
(γ,π0,η)
Forward capabilities
(leading particles)
Sophisticated Trigger(s)
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31. Participating Institutes (with Representative in the Coordination Board)
42 Institutes (35 Locations) from 9 Countries: Austria - Germany – Italy – Netherlands – Poland – Russia – Sweden – U.K. – U.S.
U Oriente, Alessandria
U Bochum
U Bonn
U & INFN Brescia
U Catania
U Cracow
GSI Darmstadt
TU Dresden
JINR Dubna I + II
U Edinburgh
U Erlangen
NWU Evanston
U & INFN Ferrara
U Frankfurt
LNF-INFN Frascati
U & INFN Genova
U Glasgow
U Gießen
KVI Groningen
IKP Jülich I + II
U Katowice
U Mainz
TU München
U Münster
BINP Novosibirsk
U Pavia
U of Silesia
U Stockholm
U Torino
Politechnico di Torino
U & INFN Trieste
U Tübingen
U & TSL Uppsala
IMEP Vienna
SINS Warsaw
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32. Competition BES, BNL, CLEO-C, DaΦne, Hall-D, JHF Topic Competitor
Confinement Charmonium
all cc states with high resolution
CLEO-C only 1–– states
Gluonic Excitations
charmed hybrids
heavy glueballs
CLEO-C light glueballs
Hall-D light hybrids
Nuclear Interactions
D-mass shift
J/ψ absorption (T~0)
DaΦne K-mass shift
Hypernuclei
γ-spectroscopy of Λ- and ΛΛ–hypernuclei
BNL indirect evidence only
JHF single HN
Open Charm Physics
Rare D-Decays
CP-physics in Hadrons
CLEO-C rare D-Decays
CP-physics in D-Mesons
ν,K-beams
JHF rare K-Decays (?)
neutrino physics
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33. high resolution spectroscopy with p-beams in formation experiments:
Why Antiprotons ?
high resolution spectroscopy with p-beams in formation experiments:
ΔE  ΔEbeam
high yields of gluonic excitations in pp
glueballs, charmed hybrids
event tagging by pair wise associated production,
(particle, anti-particle) e.g. ppDD
large √s at low momentum transfer
important for in-medium "implantation" of hadrons:
study of in-medium effects of charmed states
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34. The antiproton facility HESR @ GSI addresses many important questions
Summary & Outlook
Investigation of charmed hadrons and their interaction with matter is a mandatory task for the next decade
The antiproton facility GSI addresses many important questions
A high performance storage ring and detector are envisaged to utilize a luminosity of L=2∙1032 cm-2s-1
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