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Status N* photoproduction with CLAS

CLAS 3 rd Euroworkshop Glasgow, UK, June 20-22, 2013. Status N* photoproduction with CLAS. Eugene Pasyuk Jefferson Lab. Resonance status for N * and Δ *. Nearly half the states have only fair or poor evidence! Most states need more work to learn details Are there missing states?.

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Status N* photoproduction with CLAS

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  1. CLAS 3rdEuroworkshop Glasgow, UK, June 20-22, 2013 Status N* photoproductionwith CLAS Eugene Pasyuk Jefferson Lab

  2. Resonance status for N* and Δ* • Nearly half the states have only fair or poor evidence! • Most states need more work to learn details • Are there missing states? E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  3. Baryon Resonance Spectrum N* S. Capstik and W. Roberts R.G. Edwards et al. Phys. Rev. D84 074508 (2011) Lattice QCD Mass(π) = 396 MeV Masses, widths, and coupling constants not well known for many resonances Most models predict more resonance states than observed E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  4. From the Experiment to Theory Experiment cross section, spin observables (single) dσ/dΩ,Σ,P,T (beam-target) E,F,G,H, (beam-recoil)Cx,Cz,Ox,Oz, (target-recoil)Lx,Lz, Tx,Tz, Amplitude analysis →multipole amplitudes →phase shifts Reaction Theory dynamical frameworks Theory LQCD, quark models, QCD sum rules, … E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  5. Polarization observables in pseudoscalar meson production 4Complex amplitudes: 16real polarization observables. Complete measurement from 8carefully chosen observables. πN has large cross section but in KY recoil is self-analysing ☻ πN KY recoil targγ γ targrecoil ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ ☻☻☻ I. S. Barker, A. Donnachie, J. K. Storrow, Nucl. Phys. B95 347 (1975). Complete, and over-determined circ polarized photons longitudinally polarized target linearly polarized photons transversely polarized target E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  6. CEBAF Large Acceptance Spectrometer 1997-2012 Torus magnet 6 superconducting coils Electromagnetic calorimeters Lead/scintillator, 1296 photomultipliers target + start counter Drift chambers 35,000 cells Time-of-flight counters plastic scintillators, 684 photomultipliers Gas Cherenkov counters e/ separation, 256 PMTs E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  7. 12/18/2012 E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  8. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  9. Polarized pohoton beam Circular polarization from 100% polarized electron beam Circular polarization H. Olsen and L.C. Maximon, Phys. Rev. 114, 887 (1959) Circularly polarized beam produced by longitudinally polarized electrons Linearly polarized photons: coherent bremsstrahlung on oriented diamond crystal E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  10. FROST E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  11. HDIce polarized target Polarized at very high magnetic field and very low temperature Transferred to in-beam cryostat Spin can be moved between H and D with RF transitions All material can be polarized with small background E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  12. What we measure with CLAS γp→π0p, π+n γp→ηp γp→η’p γp→KY (K+Λ, K+Σ0, K0Σ+) γp→π+π-p ωp, ρp, ϕp …. γn→π-p γn→π+π-n γn→Σ-K+ , ΛK0 ….. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  13. Single pion production E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  14. Σ for γp →nπ+ g8b DU12 CM12 MAID BbGa 60 60 0 0 120 120 M. Dugger et al. Paper under collaboration review E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  15. Σ for γ p → p π0 g8b DU12 CM12 MAID BbGa M. Dugger et al. Paper under collaboration review E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  16. Changes in couplings Those are both **** states! E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  17. E for γ p → p π0 g9a (new) • Early stage results • Predictions agree better at lower energies M. Dugger et al. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  18. E for γ p → n π+ g9a SAID SAID (new fit) MAID W = 1.25 GeV W = 1.27 GeV W = 1.29 GeV W = 1.31 GeV W = 1.33 GeV W = 1.35 GeV PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY W = 1.45 GeV W = 1.47 GeV W = 1.37 GeV W = 1.39 GeV W = 1.41 GeV W = 1.43 GeV Predictions worse at higher energies above 1.7 GeV PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY W = 1.51 GeV W = 1.49 GeV W = 1.53 GeV W = 1.55 GeV W = 1.57 GeV W = 1.59 GeV PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY W = 1.63 GeV W = 1.61 GeV W = 1.69 GeV W = 1.71 GeV W = 1.65 GeV W = 1.67 GeV W=1.73 GeV W = 1.9 GeV W = 1.75 GeV W = 1.77 GeV W = 1.81 GeV W = 1.83 GeV PRELIMINARY W = 1.73 GeV PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY W = 1.94 GeV W = 1.98 GeV W = 2.02 GeV PRELIMINARY PRELIMINARY PRELIMINARY W = 2.07 GeV W = 2.13 GeV W = 2.19 GeV PRELIMINARY PRELIMINARY PRELIMINARY Cos(θπc.m.) S. Strauch Analysis note is being written E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  19. T for γ p → n π+ g9b (new) (new) (new) M. Dugger et al. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  20. F for γ p → n π+ g9b (new) (new) • Agreement with predictions get much worse at higher energies • SAID13 are predictions based on preliminary fits to CLAS pion Σ measurements (new) M. Dugger et al. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  21. Σ forγ n → p π- g13 • preliminary D. Sokhan Curve - SAID Red GRAAL Magenta and Blue - Erevan 9 out of 40 angular bins are shown Bins 0.04 in cos and 20 MeV in W E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  22. E forγn(p) →pπ-(p) g14 T. Kagea E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  23. ηphotoproduction E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  24. Σ forγp →pη g8b PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY • preliminary PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY SAID MAID PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY PRELIMINARY P. Collins Analysis under working group review E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  25. E forforγp →pη g9a I. Senderovich E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  26. Gforforγp →pη g9a I. Senderovich E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  27. T forforγp → pη R. Tucker E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  28. F forforγp → pη R. Tucker E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  29. KY production E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  30. Σ , Ox , Oz for γp→ K+Λ g8b D. G. Ireland, K. Livingston, B. McKinnon, C. A. Paterson E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  31. Σ , Ox , Oz for γp→ K+Σ0 g8b D. G. Ireland, K. Livingston, B. McKinnon, C. A. Paterson E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  32. T for γp→ K+Λ and γ p → K+Σ0 g8b Due to the self-analyzing nature of the , determine many observables using only a linearly polarized beam Direct measurements of T A4 – N. Walford D. G. Ireland, K. Livingston, B. McKinnon, C. A. Paterson E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  33. T for γp→K+Λ g9b W=1725 MeV Eγ=1117 MeV W=1675 MeV Eγ=1027 MeV W=1775 MeV Eγ=1210 MeV W=1825 MeV Eγ=1306 MeV ★-CLAS BnGa kaonMAID W=1975 MeV Eγ=1610 MeV W=2025 MeV Eγ=1717 MeV W=1875 MeV Eγ=1405 MeV W=1925 MeV Eγ=1506 MeV • preliminary W=2175 MeV Eγ=2053 MeV W=2275 MeV Eγ=2290 MeV W=2225 MeV Eγ=2170 MeV W=2125 MeV Eγ=1938 MeV N. Walford E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  34. T for γp → K+Σ0 g9b ★-CLAS BnGa kaonMAID W=1725 MeV Eγ=1117 MeV W=1775 MeV Eγ=1210 MeV W=1875 MeV Eγ=1405 MeV W=1825 MeV Eγ=1306 MeV • preliminary W=1975 MeV Eγ=1610 MeV W=2025 MeV Eγ=1717 MeV W=2075 MeV Eγ=1826 MeV W=1925 MeV Eγ=1506 MeV W=2125 MeV Eγ=1938 MeV W=2175 MeV Eγ=2053 MeV W=2225 MeV Eγ=2170 MeV W=2275 MeV Eγ=2290 MeV N. Walford E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  35. Ffor γp→K+Λ g9b ★-CLAS BnGa kaonMAID • preliminary N. Walford E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  36. p+p-photoproduction E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  37. Photoproduction of π+π-p states • Dominates photoproduction cross section for W >1.6 GeV • 64 observables • 28 independent relations related to helicity amplitude magnitudes • 21 independent relations related to helicity amplitude phases • Results in 15 independent numbers Could be used for search of resonances that decay into other resonances E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  38. Cross section for γp →pπ+π- E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  39. IS for pπ+π- g8b Linearly polarized photons, unpolarized target E=1900-1950 MeV W=2120 MeV Charles Hanretty One of 20 energy bins E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  40. Ifor pπ+π- g9a W. Roberts and T. Oed,PRC 71, 055201 (2005) S. Strauch et al., PRL. 95, 162003 (2005) S. Park A. Fix and H. Arenhovel,EPJA 25, 115 (2005) E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  41. Pzfor pπ+π- g9a W. Roberts and T. Oed,PRC 71, 055201 (2005) S. Park A. Fix and H. Arenhovel,EPJA 25, 115 (2005) E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  42. Pzfor pπ+π- g9a W. Roberts and T. Oed,PRC 71, 055201 (2005) S. Park A. Fix and H. Arenhovel,EPJA 25, 115 (2005) E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  43. Comparison with model: Pcz g9a preliminary A. Fix and H. Arenhovel,EPJA 25, 115 (2005) Y. Mao E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  44. Comparison with model: Psz g9a preliminary A. Fix and H. Arenhovel,EPJA 25, 115 (2005) Y. Mao E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  45. Summary of meson photoproduction ✔ -published✔- acquired E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  46. Summary Data collection with proton and deuteron targets is complete “complete (or nearly complete) measurement” in pseudoscalar meson photoproductionis in the can In many cases these are the first measurements. In most cases model predictions do not agree with the data at higher energies Phenomenological and theoretical analyses will have to deal with tenths of thousands of data points for various observables in different final states. Setting up close collaboration with Bonn-Gatchina group. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  47. Extras E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  48. Polarization observables in pseudoscalar meson production E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

  49. • Circular and Linear polarized photons • flux up to 108 s-1 tagged (low bkg) • Longitudinally polarized solid HD • P(D) ~ 22%; lifetimes ~ 2 yr • Nov/11 – May/12: 14 billion triggers g14 – E06-101: polarized gamma beams on polarized HD

  50. E. Pasyuk CLAS 3rd Euroworkshop Glasgow, UK, June 20-22, 2013

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