J. RitmanForschungszentrum Juelich The PANDA Experiment: A Facility to Map out Exotic Charmed Hadrons
Jim Ritman 2 Introduction FAIR Facility Status of the PANDA Detector Brief Overview of the Physics Program (exotic) Charmonium (exotic) Open Charm Summary
Jim Ritman 3 Facility for Antiproton and Ion Research p-Linac HESR SIS18 SIS100 CR/RESR Antiprotons Production Target
Jim Ritman 4 Areal view July 27 th, 2013 Facility for Antiproton and Ion Research
Jim Ritman 5 HESR with PANDA and Electron Cooler HESRCOSY 575 mCircumference184 m 1.5 – 15 GeV/cMomentum0.3 – 3.7 GeV/c up to 9 GeV/cElectron Coolingup to 0.5 GeV/c Full rangeStochastic Cooling1.5 – 3.7 GeV/c HESR COSY Antiprotons stored Thick target 4 · cm -2 Δp/p ≤ 4 · Lumi up to 2 · cm -2 s -1 Phase space cooling beam life time: > 30 min
Jim Ritman 6 Electron Cooler, HESR Injection energies HESR Injection energies (3.5 GeV/c) 2 MV x 1 A Installed in COSY in 2013
Jim Ritman 7 PANDA Detector Scenario High background: exclusive event reconstruction essential simultaneous neutral and charged particles close to full 4 acceptance Glueballs/Hybrids/etc.: high kaon yield PID over full forward hemisphere Resonances/Molecular states/etc.: concurrent measurement of different decay branches MVD and EMC Electromagnetic final states: e +/- and +/- EMC and Muon Detectors
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Jim Ritman p Momentum [GeV/c] Mass [GeV/c 2 ] ΛΛ ΣΣ ΞΞ ΛcΛcΣcΣcΞcΞcΛcΛcΣcΣcΞcΞc ΩcΩcΩcΩc ΩΩD DsDsDsDs qqccqqccqq nng,ssgccgccg ggg,gg light qq π,ρ,ω,f 2,K,K *c J/ψ, η c, χ cJ nng,ssgccgccg ggg ● Meson spectroscopy − light mesons − charmonium − exotic states glueballs hybrids molecules/multiquarks − open charm ●Baryon/antibaryon production ● Charm in nuclei ● Strangeness physics − Hyperatoms − S = -2 nuclear system Ξ − nuclei ΛΛ hyepernuclei E.M. processes PANDA Program
Jim Ritman 12 Hadron Spectroscopy with Antiproton Annihilation
Jim Ritman 13 Why Antiprotons? difficult to make BUT: gluon rich process gain ~2 GeV in annihilation, reduced momentum transfer all fermion-antifermion quantum numbers accessible very high resolution in formation reactions high angular momentum accessible
Jim Ritman 14 Particle production in pp collisions Formation: _ All J PC allowed for (qq) accessible in pp __ Only J PC = 1 -- allowed in e + e - (to 1st order) c.f.
Jim Ritman 15 Invariant mass reconstruction depends on the detector resolution ≈ 10 MeV High Mass/Width Resolution, e.g.: χ c1,2 Formation: Resonance scan: Resolution depends on the beam resolution ≈ 240 keVPANDA ≈ 50 keV
Jim Ritman 16 Charmonium Spectroscopy open questions below DD threshold widths, branching new „XYZ“ states (Belle, BaBar, CLEO, CDF, D0, LHCb …) masses are poorly known; often widths are just upper limits; few final states have been studied; statistics are poor; quantum number assignment is possible for few states; some resonances need confirmation… new degrees of freedom: molecules, tetraquarks, gluonic excitations? conventional states above DD high L states: access in pp but not in e + e - _ _ _
Jim Ritman 17 New Charmonium-like Discoveries X(3872) PRL 91, (2003) X(3940) PRL 98, (2007) Y(3940) PRL 94, (2005) X(3915) PRL 104, (2010) Y(4260) PRL 95, (2005) Y(4350) PRL 98, (2007) Y(4008) PRL 99, (2007) Y(4660) PRL 99, (2007) Z(4430) - PRL 100, (2008) Z 1 - & Z 2 - PRD 78, (2008) Y(4140) PRL 102, (2009) X(4350) PRL 104, (2010) in addition: many new open charm states
Jim Ritman 18 Exotics production in pp collisions Production: all J PC accessible G.Bali, EPJA 1 (2004) 1 (PS) _ Hybrids J PC exotic Exotic J PC would be clear signal
Jim Ritman 19 How can PANDA contribute? simulation studies for several channels and √s : J/ψπ + π -, J/ψπ 0 π 0, χ c γ J/ψ γγ, J/ψ γ, J/ψ η, η c γ direct formation in pp: line shapes ! d target: pn with p spectator tagging, e.g. Z - (4430) ≈ 100 events/day ≈ 40 events/day S/N =25 ε = 32 % S/N = 2 _ _ C. Hanhart et al., PRD 76 (2007) J/ D 0 D *0 _ J/ D 0 D *0 _ E. Braaten, M. Lu, PRD 77 (2008) D0D00D0D00 _ Compare lineshapes in different final states!
Jim Ritman 20 Open Charm: The D s Spectrum Th./Expt. in qualitative agreement for D states, but some details open Many new D J mesons (LHCb) new narrow states (2003): D s * (2317) and D s * (2460), (and other broad states more recently) masses significantly lower than quark model expectation, and just below DK and D * K threshold Widths are only upper limits Interpretation unclear: DK / D * K molecules, tetraquarks, chiral doublers, …? Sensitive to width
Jim Ritman 21 D s0 * (2317) Theoretical Predictions Approach (D s0 *(2317) D s 0 ) (keV) M. Nielsen, Phys. Lett. B 634, 35 (2006) 6 2 P. Colangelo and F. De Fazio, Phys. Lett. B 570, 180 (2003) 7 1 S. Godfrey, Phys. Lett. B 568, 254 (2003) 10 Fayyazuddin and Riazuddin, Phys. Rev. D 69, (2004) 16 W. A. Bardeen, E. J. Eichten and C. T. Hill, Phys. Rev. D 68, (2003) 21.5 J. Lu, X. L. Chen, W. Z. Deng and S. L. Zhu, Phys. Rev. D 73, (2006) 32 W. Wei, P. Z. Huang and S. L. Zhu, Phys. Rev. D 73, (2006) 39 5 S. Ishida, M. Ishida, T. Komada, T. Maeda, M. Oda, K. Yamada and I. Yamauchi, AIP Conf. Proc. 717, 716 (2004) H. Y. Cheng and W. S. Hou, Phys. Lett. B 566, 193 (2003) A. Faessler, T. Gutsche, V.E. Lyubovitskij, Y.L. Ma, Phys. Rev. D 76 (2007) 32.6 Y. I. Azimov and K. Goeke, Eur. Phys. J. A 21, 501 (2004) 129 43 (109 16) M.F.M. Lutz, M. Soyeaur, arXiv: [hep-ph] 140 Feng-Kun Guo, Christoph Hanhart, Siegfried Krewald, Ulf-G. Meißner Phys Lett. B 666 (2008) 40 100 Pure cs state Tetraquark state DK had. molecule Dynamically gen. res.
Jim Ritman 22 Method: Threshold Scan reaction: excitation function only depends on m and Γ of D s (2317) experimental accuracy determined by beam quality (Δp, σ p /p), not by detector resolution
Jim Ritman 23 Simulation Results: Energy Scan M sum = M miss (D s ) + M(D s ) = 100 keV
Jim Ritman 24 16% 20% 9% 30% 60% 58% x100 Ds1'(2536)+Ds0(2317)+Ds1(2460)+ Ds+ D0 00 Summary of MC Simulations Work in progress...
Jim Ritman 25 Summary Many charmonium and open charm states recently discovered Nature of these states is not clear, for some it seems to be connected to the width Pbar-P also sensitive to exotic J PC states PANDA will be able to perform high resolution -Resonance scans and -Threshold scans FAIR and PANDA progressing well towards realization
Jim Ritman 26 Thank you for you attention and Goodbye to Nara
Jim Ritman 27 The PANDA Collaboration ~500 Members from 67 Institutes 18 Countries Australia, Austria, Belarus, China, France, Germany, India, Italy, Poland, Romania, Russia, Spain, Sweden, Switzerland, Thailand, The Netherlands, USA, UK
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