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Günther Rosner FAIR UK community @ DL, 25/01/06 1
antiProton Annihilation at DArmstadt Physics programme
Quark confinement: Charmonium spectroscopyExcited gluons: Exotic hybrid mesons & glueballsNucleon spin puzzle: transverse quark spin distribution functions in the nucleonGeneralised parton distributions (in the nucleon)Time-like nucleon formfactorsModifications of hadrons in the nuclear mediumDouble Hypernuclei
Antiproton facility : HESR & PANDATimelines
PANDA
Günther Rosner FAIR UK community @ DL, 25/01/06 2
Facility for Antiproton and Ion Research
Broad range of high-intensity secondary beams
Radioactive nucleiAntiprotons
Cooler and storage ringsParallel operation
PANDA
HESR
Collector ring
SIS 18
SIS 300SIS 100
Günther Rosner FAIR UK community @ DL, 25/01/06 3
PANDA physics programmeCharmonium spectroscopy
Exotics: charmed hybrids & heavy glueballs Time-like
form factors
Medium modifications
of charmed mesons
Hard exclusiveprocesses
CP-violation(D & Λ - sector)
Hypernuclei
Drell-Yanprocesses
Günther Rosner FAIR UK community @ DL, 25/01/06 4
Strong interaction physics: QCD vs QED
QED:
QCD:
Günther Rosner FAIR UK community @ DL, 25/01/06 5
Running strong coupling constant Sα
Particle Physics Nuclear Physics
Günther Rosner FAIR UK community @ DL, 25/01/06 6
G. Bali et al.,hep-lat/0003012
Lattice QCD Confinement
aV(r) br
r= − +
q q
Distance between Quarks [fm]
Günther Rosner FAIR UK community @ DL, 25/01/06 7
Charmonium spectroscopy –a high-precision testing ground for confinement
Direct formation of charmonium in pbarpExperimental tasks
find ηc‘ (21S0) stateconfirm hc(11P1) statemeasure transition ratesidentify states above DbarDthreshold
Refine confinement potential(spin dependence?)Challenge for lattice QCD
Günther Rosner FAIR UK community @ DL, 25/01/06 8
Σ
Π
Charmed Hybrids - theory
Lattice-QCD:Σ-potential from one-gluon exchangeΠ-potential from excited gluon flux
Charmed hybrids expected atmHcc ~ 4.2 - 4.5 GeV/c2
Light charmed hybridscould be narrow, if open charm decays are inaccessible or suppressed
Σ
Π
<r2> and rBreakup
3
3.5
4
1 2
R/r0
V(R)/GeV
J/ψ
χc
ψ‘
Hcc
DD
Günther Rosner FAIR UK community @ DL, 25/01/06 9
Charmed hybrids - experiment
JPC = 0-+ 0+- 1+- 1-+ 2-+ 2+-
exotic(Exotic mesons are not generated when S=0)
Flux tube model: 1st excited state of flux tube has J=1
Combine with S=1 for quarks to get:
LS
S
1
2S = S + S1 2
J = L + S
C = (-1)L + S
P = (-1)L + 1
Quantum number rules for quark-antiquark pair:-
JPC = 0– + 0++ 1– – 1+ – 2++ …
JPC = 0– – 0+ – 1– + 2+ – …
Allowed combinations
Not-allowed: exotic
Günther Rosner FAIR UK community @ DL, 25/01/06 10
Charmed Hadrons @ PANDA
0 2 4 6 8 12 1510Antiproton momentum [GeV/c]
Mass [GeV/c2]
Two bodythresholds
Quark molecules
Gluonicexcitations
qq Mesons
1 2 3 4 5 6
Hybrids
Hybrids+Recoil
Glueball
Glueball+Recoil
ΛΛΣΣΞΞ
ΛcΛcΣcΣcΞcΞc
ΩcΩcΩΩ DDDsDs
qqqq ccqq
nng,ssg ccg
ggg,gg
light qqπ,ρ,ω,f2,K,K*
ccJ/ψ, ηc, χcJ
nng,ssg ccg
ggg
conventionalcharmonium
exoticcharmonium
Günther Rosner FAIR UK community @ DL, 25/01/06 11
Search for heavy glueballs @ PANDALight glueballs:
candidate f0(1500), 0++; Γ=110MeVno flavour blind decaymix with neighbouring scalar mesons
Heavy glueballsflavour blind decay
charmed final states!only a few charmed mesons around 3-4 MeV/c2 (less mixing!)
Exotic heavy glueballs (no mixing)m(2+-) = 4140(50)(200) MeVm(0+-) = 4740(70)(230) MeV
Morningstar & Peardon, PRD60(1999)34509Morningstar & Peardon, PRD56(1997)4043
Günther Rosner FAIR UK community @ DL, 25/01/06 12
What is needed experimentally?Gluon-rich environment
Proton-antiproton annihilation
Precision resonance scanCooled antiproton beamHigh luminosity
All quantum numbers measured
Large acceptance detector
High statistics samplesSeveral years of beamtime
Crystal Barrelf0(1500)
Günther Rosner FAIR UK community @ DL, 25/01/06 13
Nucleon structure: The spin puzzle
COMPASSRHIC
HERMES, COMPASSFNAL, PANDA, PAX
HERMESCOMPASS
PANDAJLab-upgrade
Gluon polarisationpositive (HERMES)negative (SMC)
Gluon orbitalangular momentum(in principle accessible through GPDs)
Quark orbitalangular momentum(accessible throughGPDs)
Transversity
Quark spinΔΣ ≅ 0.25
Günther Rosner FAIR UK community @ DL, 25/01/06 14
Parton distributionsLeading twist
T-odd
directlyaccessible inDrell-Yan
Chirallyodd
Günther Rosner FAIR UK community @ DL, 25/01/06 15
Drell-Yan processesCross section depends on elementary process
Measured as a function of polar angle Θ and azimuthal angle ΦDirect access to quark distribution functions(no fragmentation function involved)Complementary to Deep Inelastic Scattering (DIS)
*γ→qq
Günther Rosner FAIR UK community @ DL, 25/01/06 16
Drell-Yan processes and parton distributions
Unpolarised DY Boer-Mulders DF h1
(PANDA @ HESR)
Single or double polarisation DY transversity h1(PAX @ HESR)
Günther Rosner FAIR UK community @ DL, 25/01/06 17
Hard exclusive processes:Generalised Parton Distributions (GPD)
(*)p p γγ→Crossed channel (time-like) Compton Scattering
Hard scale:large s ~ 10 GeV2 and t~ s, or large pT
Soft part can be separated and parameterised by Generalised Parton Distribution amplitudesExperimental problem:large hadronic background (reject e.g. π0π0 kinematically)
Günther Rosner FAIR UK community @ DL, 25/01/06 18
Time-like proton form factors
Goals:To measure time-like FF from threshold up to high s = q2 in one experiment(reduced systematic error)To compare with space-like FFs (pQCD at large s?)
PANDA:Wide kinematical rangeLarge solid angle coverageLarge statistics
High-quality measurement of both GE and GM
Crossed channel :p p e e+ −→
Günther Rosner FAIR UK community @ DL, 25/01/06 19
Hadron mass shifts in the nuclear medium
A. Hayashigaki, PLB 487 (2000) 96
D−
50 MeV
D
D+
π
K
25 MeV
100 MeV
K+
K−
π−
π+HADES & CBMPseudoscalar &vector mesons ρ, ω, Φ
PANDAExtension to charm sector
Günther Rosner FAIR UK community @ DL, 25/01/06 20
Stra
nges
s
Neutron Number
Hypernuclei:Extension of the Nuclear Chart
… understanding the YN interaction
Günther Rosner FAIR UK community @ DL, 25/01/06 21
Hypernuclei
Neutrons
16Λ O 18
Λ O14Λ N 15
Λ N12Λ C 13
Λ C 14Λ C
9ΛB 10
Λ B 11Λ B 12
Λ B7ΛBe 8
ΛBe 9ΛBe10
Λ Be6ΛLi 7
ΛLi 8ΛLi 9
ΛLi4ΛHe 5
ΛHe6ΛHe 7
ΛHe 8ΛHe
4ΛH3
ΛH
1 2 3 4 5 6 7 8 9
4
8
7
6
3
5
2
1
10
9
Prot
ons
New: high resolution γ-Spectroscopy with Ge-Detectors
3rd dimensionof nuclear chart(strangeness)
Günther Rosner FAIR UK community @ DL, 25/01/06 22
Production of double Hypernuclei
Ξ-Secondary Target
Ξ-(dss)p(uud) Λ(uds)Λ(uds)
3 GeV/c
TriggerK+K
Günther Rosner FAIR UK community @ DL, 25/01/06 23
High Energy Storage Ring (HESR)
Günther Rosner FAIR UK community @ DL, 25/01/06 24
Interaction point
SolenoidDipole
EM and hadroncalorimeters
Targetgenerator
RICHDrift or wirechambers
TOF stop
Muon counters
Tracking of charged particlesIdentification of γ, e±, μ±, π±,
K±, p, anti-pHigh rate capabilityFast trigger scheme
Günther Rosner FAIR UK community @ DL, 25/01/06 25
beam
MVDStraws or TPC
mini driftchambers
coil
pellets orclusters
TOF stop
disk DIRC
barrelDIRC
electro magnetic calorimeterEMC
Günther Rosner FAIR UK community @ DL, 25/01/06 26
Timelines
FAIR contract signed by participating countries by 2006PANDA technical design report 2007/8PANDA commissioning 2012/13 in Phase II of FAIR constructionData taking 2013…
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