antiProton Annihilation at DArmstadt

1
antiProton Annihilation at DArmstadt

• Physics programme
• Quark confinement Charmonium spectroscopy
• Excited gluons Exotic hybrid mesons glueballs
• Nucleon spin puzzle transverse quark spin
  distribution functions in the nucleon
• Generalised parton distributions (in the nucleon)
• Time-like nucleon formfactors
• Modifications of hadrons in the nuclear medium
• Double Hypernuclei
• Antiproton facility HESR PANDA
• Timelines

2
Facility for Antiproton and Ion Research
SIS 100
SIS 300
SIS 18

• Broad range of high-intensity secondary beams
• Radioactive nuclei
• Antiprotons
• Cooler and storage rings
• Parallel operation

PANDA
HESR
Collector ring
3
PANDA physics programme
Charmonium spectroscopy
Exotics charmed hybrids heavy glueballs
Time-like form factors
Medium modificationsof charmed mesons
Drell-Yanprocesses
Hard exclusiveprocesses
CP-violation(D ? - sector)
Hypernuclei
4
Strong interaction physics QCD vs QED
QED
QCD
5
Running strong coupling constant
Particle Physics
Nuclear Physics
6
Lattice QCD ? Confinement
Distance between Quarks fm
G. Bali et al.,hep-lat/0003012
7
Charmonium spectroscopy a high-precision
testing ground for confinement

• Direct formation of charmonium in pbarp
• Experimental tasks
• find ?c (21S0) state
• confirm hc(11P1) state
• measure transition rates
• identify states above DbarD threshold
• Refine confinement potential(spin dependence?)
• Challenge for lattice QCD

8
Charmed Hybrids - theory

• Lattice-QCD
• S-potential from one-gluon exchange
• P-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

V(R)/GeV
Hcc
4
DD
3.5
3
R/r0
2
1
ltr2gt and rBreakup
9
Charmed hybrids - experiment
Quantum number rules for quark-antiquark pair-
JPC 0 0 1 1 2
Allowed combinations
JPC 0 0 1 2
Not-allowed exotic
Combine with S1 for quarks to get
Flux tube model 1st excited state of flux tube
has J1
JPC 0- 0- 1- 1- 2- 2-
exotic
(Exotic mesons are not generated when S0)
10
Charmed Hadrons _at_ PANDA
11
Search for heavy glueballs _at_ PANDA

• Light glueballs
• candidate f0(1500), 0 ?110MeV
• no flavour blind decay
• mix with neighbouring scalar mesons
• Heavy glueballs
• flavour 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) MeV
• m(0-) 4740(70)(230) MeV

Morningstar Peardon, PRD60(1999)34509Morningsta
r Peardon, PRD56(1997)4043
12
What is needed experimentally?

• Gluon-rich environment
• Proton-antiproton annihilation
• Precision resonance scan
• Cooled antiproton beam
• High luminosity
• All quantum numbers measured
• Large acceptance detector
• High statistics samples
• Several years of beamtime

13
Nucleon structure The spin puzzle
COMPASSRHIC
Gluon orbitalangular momentum(in principle
accessible through GPDs)
Gluon polarisationpositive (HERMES)negative
(SMC)
HERMESCOMPASSPANDAJLab-upgrade
Quark spin?? ? 0.25
Quark orbitalangular momentum(accessible
through GPDs)
Transversity
HERMES, COMPASSFNAL, PANDA, PAX
14
Parton distributions
Leading twist
directlyaccessible in Drell-Yan
Chirally odd
T-odd
15
Drell-Yan processes

• Cross section depends on elementary process
• Measured as a function of polar angle ? and
  azimuthal angle ?
• Direct access to quark distribution functions(no
  fragmentation function involved)
• Complementary to Deep Inelastic Scattering (DIS)

16
Drell-Yan processes and parton distributions

• Unpolarised DY ? Boer-Mulders DF h1- (PANDA _at_
  HESR)

• Single or double polarisation DY ?transversity
  h1(PAX _at_ HESR)

17
Hard exclusive processesGeneralised Parton
Distributions (GPD)
Crossed channel (time-like) Compton Scattering

• Hard scalelarge s 10 GeV2 and t s, or
  large pT
• Soft part can be separated and parameterised by
  Generalised Parton Distribution amplitudes
• Experimental problemlarge hadronic background
  (reject e.g. ?0?0 kinematically)

18
Time-like proton form factors
Crossed channel

• 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 range
• Large solid angle coverage
• Large statistics
• High-quality measurement of both GE and GM

19
Hadron mass shifts in the nuclear medium

• HADES CBM
• Pseudoscalar vector mesons ?, ?, F
• PANDA
• Extension to charm sector

20
HypernucleiExtension of the Nuclear Chart
understanding the YN interaction
21
Hypernuclei
3rd dimension of nuclear chart (strangeness)
New high resolution ?-Spectroscopy with
Ge-Detectors
22
Production of double Hypernuclei
?-
?-(dss)p(uud) ? ?(uds)?(uds)
23
High Energy Storage Ring (HESR)
24
Target generator
Muon counters
EM and hadron calorimeters
Solenoid
Dipole
RICH

• Tracking of charged particles
• Identification of ?, e, µ, p, K, p, anti-p
• High rate capability
• Fast trigger scheme

25
(No Transcript)
26
Timelines

• FAIR contract signed by participating countries
  by 2006
• PANDA technical design report 2007/8
• PANDA commissioning 2012/13 in Phase II of FAIR
  construction
• Data taking 2013