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Quests for PANDA experiment

Quests for PANDA experiment. Eugene A. Strokovsky Joint Institute for Nuclear Research Veksler-Baldin Laboratory of High Energy for the  PANDA Collaboration. at Conference NEW TRENDS IN HIGH-ENERGY PHYSICS (experiment, phenomenology, theory)

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Quests for PANDA experiment

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  1. Quests forPANDA experiment Eugene A. Strokovsky Joint Institute for Nuclear Research Veksler-Baldin Laboratory of High Energy for the PANDA Collaboration at Conference NEW TRENDS IN HIGH-ENERGY PHYSICS (experiment, phenomenology, theory) Alushta, Crimea, Ukraine, September 3 - 10, 2011 E.A.S., Alushta, 09.09.11

  2. Plan of the talk • The FAIR complex (Facility for Antiproton and Ion Research) • The HESR (High Energy Storage Ring) and PANDA Detector • (dedicated talk: Tibor Keri for PANDA Collaboration) • PANDA for physics of strong interactions (main topics) • Selected points of thePANDA Physics Program • Conclusions E.A.S., Alushta, 09.09.11

  3. The FAIR complex (Facility for Antiproton and Ion Research) E.A.S., Alushta, 09.09.11

  4. E.A.S., Alushta, 09.09.11

  5. Research Communities at FAIR SIS 100/300 Nuclear Matter Physics with 35-45 GeV/u HI beams, x1000 CBM HADES HESR Rare Isotope Production Target Hadron Physics with antiprotons of1.5 - 15 GeV/c Super FRS Antiproton Production Target Plasma Physics: x600 higher target energy density 600kJ/g Nuclear Structure & Astrophysics withrare isotope beams, x10 000 and excellent cooling FLAIR CR- RESR • Special Features: • 50ns Bunched beams • Electron cooling of secondary beams • SC magnets fast ramping • Parallel operation NESR High EM Field (HI) _ Fundamental Studies(HI & p) Applications (HI) 100 m From talk by B. Sharkov (March 2010 at PANDA meeting)

  6. Planned beam parameter of the SIS100/300 facility E.A.S., Alushta, 09.09.11

  7. Planned for 2016-2017 Planned: after 2017 E.A.S., Alushta, 09.09.11

  8. The HESR (High Energy Storage Ring) and PANDA Detector • (dedicated talk: Tibor Keri for PANDA Collaboration) E.A.S., Alushta, 09.09.11

  9. Storage and acceleration of antiprotons • Production rate 2x107/sec • Pbeam = 1.5 - 15 GeV/c • (2.25 < s < 5.47 GeV) • Nstored= 5x1010antiprotons • Internal Target High resolution mode • dp/p ~ 10-5(electron cooling) • Luminosity: 1031 cm-2 s-1 PANDA High luminosity mode • Luminosity: 2 x 1032 cm-2s-1 • dp/p ~ 10-4(stochastic cooling) injection E.A.S., Alushta, 09.09.11

  10. At present collaboration has more than 430 physicists from 56 institutions of  17 countries Austria – Belarus - China - Finland - France - Germany –India - Italy – Netherlands Poland – Romania - Russia – Spain - Sweden – Switzerland - U.K. – U.S.A… Basel, Beijing, Bochum, Bonn, IFIN Bucharest, Catania, Cracow, Dresden, Edinburg, Erlangen, Ferrara, Frankfurt, Genova, Giessen, Glasgow, GSI, Inst. of Physics Helsinki, FZ Jülich, JINR Dubna, Katowice, Lanzhou, LNF, Mainz, Milano, Minsk, TU München, Münster, Northwestern, BINP Novosibirsk, Pavia, PiemonteOrientale, IPN Orsay, IHEP Protvino, PNPI St. Petersburg, Stockholm, U Torino, INFN Torino, Torino Politecnico, Trieste, TSL Uppsala, Tübingen, Uppsala, Valencia, SINS Warsaw, TU Warsaw, AAS Wien E.A.S., Alushta, 09.09.11 http://www.gsi.de/panda

  11. PANDA for physics of strong interactions (main topics) E.A.S., Alushta, 09.09.11

  12. PANDA Physics Program • QCD BOUND STATES • CHARMONIUM • Gluonic excitations (hybrids, glueballs) • Strange and charmed baryons • NON-PERTURBATIVE QCD DYNAMICS • HADRONS IN THE NUCLEAR MEDIUM • PHYSICS OF HYPERNUCLEI • NUCLEON STRUCTURE • Generalized distribution amplitudes (GDA) • Matveev-Muradyan-Tavkhelidze-Drell-Yan • Electromagnetic formfactors (time-like region)viapp  e+e- (or +-) • ELECTROWEAK PHYSICS • CP-Violation and Mixing in the Charm-Sector • CP-Violation in Hyperon Decays • Rare Decays The study of QCD bound states is of fundamental importance for quantitative understanding of QCD. Precision measurements are needed to distinguish between the different approaches and identify the relevant degrees of freedom. Example of hard exclusive meson production FAIR/PANDA/Physics Book hep-ex0903-3905v1 E.A.S., Alushta, 09.09.11

  13. QCD Systems to be studied in Panda E.A.S., Alushta, 09.09.11

  14. CHARMONIUM NOTE: open problems and questions concerning charmonium were presented by I.Denisenko in his talk on Sept. 4 (Sunday) about BES-III results. Therefore here only main PANDA specific features are considered. E.A.S., Alushta, 09.09.11

  15. Charmonium Spectroscopy E.A.S., Alushta, 09.09.11

  16. Resonance formation cross section Measured rate (yield) CM Energy Beam profile Resonance Scan in pp Annihilation The cross section for the resonance formation processpp cc  final state is given by the Breit-Wigner formula: The number of detected final state events (Nevent) is a convolution of the BW cross section and the beam energy spread function f(Ecm,Ecm): The resonance mass MR , total width R and the product BrinBrout of branching ratios into the initial and final state can be extracted by measuring the formation rate Nevent for that resonance as a function of the cm energy Ecm. E.A.S., Alushta, 09.09.11

  17. CBall E835 100 cc1 1000 _ • in pp annihilation all • mesons can be formed CBall ev./2 MeV E 835 ev./pb ECM 3500 3510 3520 MeV Cball: Edwards et al. PRL 48 (1982) 70 E835: Ambrogiani et al., PRD 62 (2000) 052002 Mass resolution with PANDA: factor ~ 10 better: Dp/p = 10-5  DM < 20 keV • In e+e- annihilation via • virtual photon: only • states with JPC = 1-- • Other states: only via radiative • transitions, 2-photon processes etc. • Good mass resolution for JPC = 1--; • Other states - detector is limited. • Measurement of sub-MeV widths: • impossible. From A.Gillitzer, talk at “QCD exotics”, Bad Honnef, Jan. 2005 E.A.S., Alushta, 09.09.11

  18. Charmonium at PANDA • At 21032cm-2s-1 accumulate 8 pb-1/day (assuming 50% overall efficiency)  104107 (cc) states/day. Total integrated luminosity: 1.5 fb-1/year (at 21032cm-2s-1, assuming 6 months/year data taking). • Improvements with respect to Fermilab E760/E835: • - Up to 10 times higher instantaneous luminosity. • - Better beam monochromaticity: p/p = 10-5(FAIR) vs 210-4 (FNAL) • - Better detector (higher angular acceptance, magnetic field, ability to detect hadronic decay modes). • Fine scans to measure masses to  100 KeV, widths to  10 %. • Explore entire region below and above open charm threshold. • Decay channels: J/+X , J/  e+e-, J/  +-  hadrons DD • Precision measurement of known states • Find missing states (e.g. D states) • Understand newly discovered states • Get a complete picture of the dynamics of • the cc system. E.A.S., Alushta, 09.09.11

  19. NON-PERTURBATIVE QCD DYNAMICS In the quark picture hyperon pair production either involves the creation of a quark-antiquark pair or the knock-out of such pairs out of the nucleon sea. Hence, the creation mechanism of qq pairs and their arrangement to hadrons can be studied by measuring the reactions of the type pp  YY, where Y is a hyperon. By comparing several reactions involving different quark flavours, the OZI rule (and it's possible violation) can be tested for different levels of disconnected quark-line diagrams separately. In particlular, the reactions are interesting. Here some spin observables can be measured, including those for the case. E.A.S., Alushta, 09.09.11

  20. MC simulation Polarization of  from E.A.S., Alushta, 09.09.11

  21. Study of the OZI rule violation at PANDA Study of the LEAR unresolved puzzles: Annihilation into , , , f’2(1525),  Pontecorvo reactions pdn, K+-, K0  (high 4-momentum transfer squared!) Search for effects of nucleon polarized strangeness COMPASS: • If it were a normal quark reaction • ()exp~ 4 b • why is it so large? • () is not measured From talk by M.G.Sapozhnikov (ITEP, 2008) E.A.S., Alushta, 09.09.11

  22. In experiments at LEAR • Strong violation of the OZI rule • was found in: • pp • pp, • pp (3S1) • pdn (Pontecorvo reaction) • Does it depend upon: • spin • orbital angular momentum • momentum transfer • Isospin? (M.G.S. (ITEP, 2008)) E.A.S., Alushta, 09.09.11

  23. Pontecorvo reactions (lightest nuclei case) pd n : highest momentum transfer to meson produced inpp or pd interactions. R(n/n) = (15629) 10-3 How will it change with energy? Two-step model: pd n  1) pp  2)  N  N R(n/n) - decreases with energy Is it the correct model? pd K+- , K0  R(K+- / K0  )=0.920.15 (exp) = 0.012 (theory) M.G.S. (ITEP, 2008) E.A.S., Alushta, 09.09.11

  24. pp    at PANDA Luminosity of HESR: L =2  1032 cm-2 s-1 Cross section  = 4 b at 1.4 GeV/c BR of charged mode =0.25 Registration efficiency = 0.01 N = L   = 2 1032 4 10-300.25  0.01 = 2 s-1 Best world statistics – 1.5 hours pp    (K* K*, ) must be measured Search for the tensor glueball pp,   , K* K*,  as well M.G.S. (ITEP, 2008) E.A.S., Alushta, 09.09.11

  25. HADRONS IN THE NUCLEAR MEDIUM E.A.S., Alushta, 09.09.11

  26. The topic “hadrons in medium” has rather long history. The pre-historical examples: life-time of neutron in stable nuclei drastically differs from it's life-time in the empty space; life-time of the -hyperon in free state differs from it's life-time in hypernuclei and depends on the atomic number of a nuclei. Next stage came with pions in nuclei and with the problem of the pion condensate. Here the contributions by A.Migdal, G.Brown, T.Ericsson and M.Ericsson, W.Weise must be mentioned. Good lessons were obtained in inclusive and exclusive experiments on excitation of the -isobar in nuclei (end of ‘80-begin of ‘90). They stimulated theorists; contributions by E.Oset, V.Dmitriev, S.Fayans, S.Hirenzaki and others must be mentioned with respect to the topic under discussion. One of the approaches appeared at that time was partial restoration of the SU(4) symmetryin nuclear medium. Another approach was based on collective phenomena when pion propagates in (finite !) nuclear medium. At last decades new aspect was found by theorists and experimentalists. That was related with the deeply bound pionic atoms and with the subthreshold (or cumulative) production of K+ and K-. It resulted in concept of the partial restoration of the chiral symmetry in nuclear medium. It is this concept which is in use at modern discussions of the topic. E.A.S., Alushta, 09.09.11

  27. -propagation and  in nuclear matter Change of the -peak position and width in nuclei (also in (t,3He), (p,p’)) A>6 Total cross section (3He,t) free proton (p,n) photoabsorption Fermi-motion of a nucleon Deuteron target E.A.S., Alushta, 09.09.11

  28. Measure J/ and D production cross section in p annihilation on nuclear targets. Lowering of the D+D- mass would allow charmonium states to decay into this channel, thus resulting in increase of width: (1D) 20 MeV  40 MeV (2S) .28 MeV  2.7 MeV Study relative changes of yield and width of the charmonium states. In medium mass to be reconstructed from dilepton (cc) or hadronic decays (D) Example of mass spectra calculations • Light quarks are sensitive to quark condensate • (cc) states are sensitive to gluon condensate • D mesons are the QCD analog of the H-atom. • chiral symmetry to be studied on a single light quark • theoretical calculations disagree in size and sign • of mass shift (50 MeV/c2 attractive – 160 MeV/c2 repulsive) E.A.S., Alushta, 09.09.11

  29. Other points concerning hadrons in the nuclear medium Charmonium dissociation The goal is to measure total cross section of the J/ - nucleon interaction. The method: measuring A-dependence of the J/ yield, detecting J/ by e+e-or +- modes. Similarly (with some differences) ’ dissociation can be studied. Production of antibaryons and antikaons off nuclei The goal is to extract information about antiproton and anti- (as well as anti-kaon) nuclear potential by implanting these particles into the interior of a nucleus. This can be done at kinematics close to the recoiless kinematical condition by choosing proper antiproton energy. Colour transparency The idea is to compare yields of exclusive production of hadron pairs at large angles (close to 90 degr. c.m.) on proton and nuclear target and extract the so-called transparency ratio . The reactions are: For details see FAIR/PANDA/Physics Book (hep-ex0903-3905v1) E.A.S., Alushta, 09.09.11

  30. PHYSICS OF HYPERNUCLEI E.A.S., Alushta, 09.09.11

  31. Hypernuclei, systems where at least one nucleon is replaced by at least one hyperon (Y), allow access to a whole set of nuclear states with extra degree of freedom: the strangeness. • Probe of nuclear structure and it's possible modifications due to the hyperon. • Test and define shell model parameters. • Description in term of quantum field theories and EFT. • Study of the YN and YY forces; baryon-baryon interaction. • Weak decays (N suppressed, NNN and NN allowed  weak interaction of 4-baryons) • Hyperatoms (or multi-strange atoms) • Hypernuclei as doorway to exotic quark states (like H-dibaryon). • Experimentally: more than 50 years of study  35 single, 6 double • hypernuclei established E.A.S., Alushta, 09.09.11

  32. Production of Double Hypernuclei 2. Slowing down and capture of X- in secondary target nucleus Kaons _ trigger _ X p X-capture: X-p  LL +28 MeV 3 GeV/c X- g X-(dss) p(uud) L(uds) L(uds) 1. Hyperon- antihyperon production at threshold L g L +28MeV 3. g-spectroscopy with Ge-detectors E.A.S., Alushta, 09.09.11

  33. The PANDA experiment will use the antiproton beam from the HESR colliding with an internal proton (for a number of topics – nuclear) target and a general purpose spectrometer to carry out a rich and diversified hadron physics program. The experiment is being designed to fully exploit the extraordinary physics potential arising from the availability of high-intensity, cooled antiproton beams. The aim of the rich experimental program is to improve our knowledge of the strong interaction and of hadron structure. Significant progress beyond the present understanding of the field is expected due to improvements in statistics and precision of the data. For details see FAIR/PANDA/Physics Book (hep-ex0903-3905v1) Start of the physics is planned from end of 2017 (i.e. in 6 years) E.A.S., Alushta, 09.09.11

  34. PANDA Detector The detector description: in dedicated talk by Tibor Keri E.A.S., Alushta, 09.09.11

  35. THANK YOU! E.A.S., Alushta, 09.09.11

  36. Backups E.A.S., Alushta, 09.09.11

  37. DVCS can be described by the handbag diagram, as there is factorisation between the upper `hard' part of the diagram which is described by perturbative QCD and QED, and a lower `soft' part that is described by GPDs. The handbag diagram may describe the inverted WACS process pp at PANDA energies. E.A.S., Alushta, 09.09.11

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