PANDA. antiproton Annihilation at DArmstadt

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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 PANDA Günther Rosner FAIR UK DL, 25/01/06 1

2 Facility for Antiproton and Ion Research SIS 100 SIS 300 SIS 18 Collector ring HESR PANDA Broad range of high-intensity secondary beams Radioactive nuclei Antiprotons Cooler and storage rings Parallel operation Günther Rosner FAIR UK DL, 25/01/06 2

3 PANDA physics programme Charmonium spectroscopy Exotics: charmed hybrids & heavy glueballs Time-like form factors Medium modifications of charmed mesons Drell-Yan processes CP-violation (D & Λ - sector) Hard exclusive processes Hypernuclei Günther Rosner FAIR UK DL, 25/01/06 3

4 Strong interaction physics: QCD vs QED QED: QCD: Günther Rosner FAIR UK DL, 25/01/06 4

5 Running strong coupling constant α S Particle Physics Nuclear Physics Günther Rosner FAIR UK DL, 25/01/06 5

6 Lattice QCD Confinement q q V(r) a = + r br Distance between Quarks [fm] G. Bali et al., hep-lat/ Günther Rosner FAIR UK DL, 25/01/06 6

7 Charmonium spectroscopy a high-precision testing ground for confinement Direct formation of charmonium in p bar p Experimental tasks find η c (2 1 S 0 ) state confirm h c (1 1 P 1 ) state measure transition rates identify states above D bar D threshold Refine confinement potential (spin dependence?) Challenge for lattice QCD Günther Rosner FAIR UK DL, 25/01/06 7

8 Charmed Hybrids - theory Lattice-QCD: Σ-potential from one-gluon exchange Π-potential from excited gluon flux Charmed hybrids expected at m Hcc ~ GeV/c 2 Light charmed hybrids could be narrow, if open charm decays are inaccessible or suppressed V(R)/GeV ψ χ c H cc Π Σ DD J/ψ R/r <r 2 > and r Breakup Günther Rosner FAIR UK DL, 25/01/06 8

9 Charmed hybrids - experiment S 1 L S 2 S = S + S 1 2 J = L + S P = (-1) L + 1 C = (-1) L + S Quantum number rules for quark-antiquark pair:- J PC = Allowed combinations J PC = Not-allowed: exotic Flux tube model: 1 st excited state of flux tube has J=1 Combine with S=1 for quarks to get: J PC = exotic (Exotic mesons are not generated when S=0) Günther Rosner FAIR UK DL, 25/01/06 9

10 Charmed PANDA Antiproton momentum [GeV/c] Two body thresholds ΛΛ ΣΣ ΞΞ ΩΩ DD D s D s Λ c Λ c Σ c Σ c Ξ c Ξ c Ω c Ω c Quark molecules qqqq ccqq Gluonic Hybrids excitations Hybrids+Recoil Glueball nng,ssg nng,ssg ggg,gg ccg ccg exotic charmonium Glueball+Recoil ggg qq Mesons light qq π,ρ,ω,f 2,K,K * cc J/ψ, η c, χ cj conventional charmonium Mass [GeV/c 2 ] Günther Rosner FAIR UK DL, 25/01/06 10

11 Search for heavy PANDA Light glueballs: candidate f 0 (1500), 0 ++ ; Γ=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/c 2 (less mixing!) Exotic heavy glueballs (no mixing) m(2 +- ) = 4140(50)(200) MeV m(0 +- ) = 4740(70)(230) MeV Morningstar & Peardon, PRD60(1999)34509 Morningstar & Peardon, PRD56(1997)4043 Günther Rosner FAIR UK DL, 25/01/06 11

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 Crystal Barrel f 0 (1500) Günther Rosner FAIR UK DL, 25/01/06 12

13 Nucleon structure: The spin puzzle COMPASS RHIC Gluon polarisation positive (HERMES) negative (SMC) Quark spin ΔΣ 0.25 Gluon orbital angular momentum (in principle accessible through GPDs) Quark orbital angular momentum (accessible through GPDs) HERMES COMPASS PANDA JLab-upgrade Transversity HERMES, COMPASS FNAL, PANDA, PAX Günther Rosner FAIR UK DL, 25/01/06 13

14 Parton distributions Leading twist Chirally odd directly accessible in Drell-Yan T-odd Günther Rosner FAIR UK DL, 25/01/06 14

15 Drell-Yan processes Cross section depends on elementary process qq γ * Measured as a function of polar angle Θ and azimuthal angle Φ Direct access to quark distribution functions (no fragmentation function involved) Complementary to Deep Inelastic Scattering (DIS) Günther Rosner FAIR UK DL, 25/01/06 15

16 Drell-Yan processes and parton distributions Unpolarised DY Boer-Mulders DF h 1 HESR) Single or double polarisation DY transversity h1 HESR) Günther Rosner FAIR UK DL, 25/01/06 16

17 Hard exclusive processes: Generalised Parton Distributions (GPD) Crossed channel (time-like) Compton Scattering pp γγ (*) Hard scale: large s ~ 10 GeV 2 and t ~ s, or large p T Soft part can be separated and parameterised by Generalised Parton Distribution amplitudes Experimental problem: large hadronic background (reject e.g. π 0 π 0 kinematically) Günther Rosner FAIR UK DL, 25/01/06 17

18 Time-like proton form factors Crossed channel pp e + e : Goals: To measure time-like FF from threshold up to high s = q 2 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 G E and G M Günther Rosner FAIR UK DL, 25/01/06 18

19 Hadron mass shifts in the nuclear medium HADES & CBM Pseudoscalar & vector mesons ρ, ω, Φ PANDA Extension to charm sector π K D π π + K + D 50 MeV D + 25 MeV 100 MeV K A. Hayashigaki, PLB 487 (2000) 96 Günther Rosner FAIR UK DL, 25/01/06 19

20 Hypernuclei: Extension of the Nuclear Chart Strangess Neutron Number understanding the YN interaction Günther Rosner FAIR UK DL, 25/01/06 20

21 Hypernuclei 3 rd dimension of nuclear chart (strangeness) Protons Λ O 14 Λ N 15 Λ N 12 Λ C 13 Λ C 14 Λ C 9 ΛB 10 Λ B 11 Λ B 12 Λ B 7 ΛBe 8 ΛBe 9 ΛBe 10 Λ Be 6 ΛLi 7 ΛLi 8 ΛLi 9 ΛLi 4 He 5 He 6 He 7 He 8 He Λ Λ Λ Λ Λ 3 ΛH 4 ΛH 18 Λ O Neutrons New: high resolution γ-spectroscopy with Ge-Detectors Günther Rosner FAIR UK DL, 25/01/06 21

22 Production of double Hypernuclei K+K Trigger 3 GeV/c Ξ - Secondary Target Ξ - (dss)p(uud) Λ(uds)Λ(uds) Günther Rosner FAIR UK DL, 25/01/06 22

23 High Energy Storage Ring (HESR) Günther Rosner FAIR UK DL, 25/01/06 23

24 Target generator Muon counters TOF stop Solenoid Dipole EM and hadron calorimeters Interaction point Drift or wire chambers RICH Tracking of charged particles Identification of γ, e ±, μ ±, π ±, K ±, p, anti-p High rate capability Fast trigger scheme Günther Rosner FAIR UK DL, 25/01/06 24

25 pellets or clusters TOF stop coil barrel DIRC Strawsor TPC MVD beam mini drift chambers EMC electro magnetic calorimeter disk DIRC Günther Rosner FAIR UK DL, 25/01/06 25

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 Günther Rosner FAIR UK DL, 25/01/06 26