1. PAC Meeting Proposal A2-7/05 Mainz, 29th September 2005 Andreas Thomas Helicity Dependence of Meson Photoproduction on the Proton 650h approved with A

2. Technical concept: Tagged CW photon beam 4  - detector Frozen spin target (30mKelvin, 0.4Tesla) Horizontal Dilution refrigerator Beam along cryostat axis  symmetric,   Thin internal holding coil on shield (longitudinal,transverse) Loading along cryostat axis The new Frozen Spin Target for Crystal Ball Similar to Bonn Target [C.Bradtke et al., NIM A436, 430 (1999)]

4. 2) More detailed information on resonance properties and multipole amplitudes by investigating the helicity structure of partial reaction channels 2) More detailed information on resonance properties and multipole amplitudes by investigating the helicity structure of partial reaction channels GDH-physics on the proton 1) Test of the GDH sum rule Circularly polarized photons on longitudinally polarized protons

6. E  (GeV)I GDH (mb) 0.14-0.20MAID03 SAID04 -29 -28 0.20-2.90Measured (Mainz+Bonn) 254±5±12 > 2.90 (Regge approach) Simula et al. Bianchi-Thomas ~ -13 ~ -14 Total ~ 212 GDH sum rule 205 GDH sum rule on the proton D.Drechsel et al. Phys. Rev. D 63, 114010 (2001) Gerasimov-Drell-Hearn sum rule and related integrals GDH sum rule verified for the proton

7. E  max =430MeV LEGS, A.Sandorfi, PWA BadHonnef: Good aggreement in measured range, But Problem:  0 extrapolation in Forward direction ??

8. 2) More detailed information on resonance properties and multipole amplitudes by investigating the helicity structure of partial reaction channels 2) More detailed information on resonance properties and multipole amplitudes by investigating the helicity structure of partial reaction channels status of present results and future goals: single   - production (D 13 (1520), F 15 (1680))  - production (F 15 (1680), P 11 (1710)) double   - production (D 13 (1520), P 11 (1440), P 11 (1710)) Helicity Dependence of Meson Photoproduction

9. Partial reaction channels Input for PWA to extract resonance parameters Measurements in 1998 and 2003 at MAMI with DAPHNE and Bonn PT

10. Quark Model Classification of Baryons qqq; only uds Oktett Dekuplett Simple Constituent quark picture: Proton p(938):|uud> ~ |  > Spin 1/2 Delta  (1232):|uud> ~ |  > Spin 3/2 M1-Transition (Small 2.5% E2)

11. Connection between and and Multipoles and Resonances  NN  -prod.   Ratio  p p   E  [MeV]  b] MAID2000 [Phys. Rev. Lett. 84, 5950 (2000)]  p n   E  [MeV]

12. Connection between and and Multipoles and Resonances  NN Resonanz D 13 (1520)

14. MAID2003

16.  Photoproduction DSGE MAID2003 Dominated by S 11 (1535) at low photon energy  E=1  calibration P B P T

17.  Photoproduction MAID2003 DSGE

18.    Photoproduction DSGE KAON-MAID e.g. Missing resonance D 13 (1900)

19. 2  0 Photoproduction

20. Physics Letters B 624 (2005) 173-180 Hirata et al., Phys. Rev. C 67, 034601 (2003) Nacher et al., Nucl. Phys. A 697, 372 (2002) Improve, extend to higher energies, angular distributions and invariant masses for    and   

22. E  min =700MeV

23. E  min ~400MeV E 0 =1200MeV Bonn [R.Beck]

27. Experimental equipment Standard CB-TAPS (mini-TAPS) Cerenkov-detector Polarized frozen-spin target under preparation (P.Pedroni, P. Bartolomez) Upgraded Tagger with Moeller Polarimeter

28. Beam time estimate Reactions: Helicity asymmetry:  = dilution, Background, P= P  P T Required beam time: Polarization: Efficiency (detection and reconstruction) Goal: Target: in 2 cm butanol (includ. dilution and filling factors) dilution factor background from butanol and walls, He Beam: Data acquisition capability: 1000 events/s (800 to 1400 MeV) in    MeV

29. Beam time estimate  t = 250 h (800 -1400 MeV) 250 h (500 - 800 MeV) 150 h (200 – 500 MeV) 100 h target polarization, flux, Moeller, etc. 800 h total (polarized) In addition about 200 h with liq. Hydrogen (in combination with other measurements) For  and      reduced binning and stat. accuracy

30. Summary helicity observables carry valuable information on resonance properties and reaction mechanisms Main goal: single  0 - production (D13 (1520), F15 (1680))  - production (F15 (1680), P11 (1710)) double  0 - production (D13 (1520), P11 (1440), P11 (1710)) In addition: charged  - production

31. Hyperon Photoproduction  p  K + +  p +  - (~ 64%) n +  0 (~ 36%)   p  K + +    Important for investigations of nucleon resonances A crucial test of QCD based chiral perturbation theories in the strange quark sector T C Jude, The University of Edinburgh, Strangeness Photoproduction A2 Collaboration meeting, Mainz, September 2008 Threshold Energy ~ 911 MeV Threshold Energy ~ 1046 MeV

32. Identifying strange mesons K +     (~ 63%) Mean lifetime of K + ~ 12 ns     (~ 21%) First cluster from K + < 3ns Secondary cluster from K +      decay > 10ns A new method of tagging a strange meson reaction channel Identify the K + decay within the crystals of the Crystal Ball T C Jude, The University of Edinburgh, Strangeness Photoproduction A2 Collaboration meeting, Mainz, September 2008

33. J.Brudvik, J.Goetz, B.M.K.Nefkens, S.N.Prakhov, A.Starostin, and I.Suarez, University of California, Los Angeles, CA, USA P.Aguar, J.Ahrens, H.J.Arends, D.Drechsel, E.Heid, O.Jahn, D.Krambrich, M.Martinez, M.Rost, S.Scherer, A.Thomas, L.Tiator, D. von Harrach and Th.Walcher, Institut für Kernphysik, University of Mainz, Germany R.Beck, M.Lang, A.Nikolaev, S.Schumann, and M.Unverzagt, Helmholtz--Institut für Strahlen- und Kernphysik, Universität Bonn, Germany S.Altieri, A.Braghieri, A.Panzeri, P.Pedroni, T.Pinelli, and T.Rostomyan, INFN Sezione di Pavia, Pavia, Italy J.R.M.Annand, R.Codling, E.Downie, D.Glazier, J.Kellie, K.Livingston, J.C.McGeorge, I.J.D.MacGregor, R.O.Owens, D.Protopopescu, G.Rosner, Department of Physics and Astronomy, University of Glasgow, Glasgow, UK C.Bennhold, W.Briscoe, H.Haberzettl, Y.Ilieve, A.Kudryavtsev, and I.Strakovsky, George Washington University, Washington, USA S.N.Cherepnya, L.V.Fil'kov, and V.L.Kashevarov, B.N. Lebedev Physical Institute, Moscow, Russia V.Bekrenev, S.Kruglov, A.Kulbardis, and N.Kozlenko, Petersburg Nuclear Physics Institute, Gatchina, Russia B.Boillat, C.Carasco, B.Krusche, F.Pheron, and F.Zehr, Institut für Physik University of Basel, Basel, Ch P.Drexler, F.Hjelm, M.Kotulla, K.Makonyi, V.Metag, R.Novotny, M.Thiel, and D.Trnka, II. Physikalisches Institut, University of Giessen, Germany D.Branford, K.Foehl, C.M.Tarbert and D.P.Watts, School of Physics, University of Edinburgh, Edinburgh, UK G.M.Gurevich, V.Lisin, R.Kondratiev and A.Polonski, Institute for Nuclear Research, Moscow, Russia J.W.Price, California State University, Dominguez Hills, Carson, CA, USA D.Hornidge, Mount Allison University, Sackville, NB, Canada P.Grabmayr and T.Hehl, Physikalisches Institut, Universität Tübingen, Tübingen, Germany N.S.Borisov, S.B.Gerasimov, and Yu.A.Usov, JINR, Dubna, Russia H.Staudenmaier, Universität Karlsruhe, Karlsruhe, Germany D.M.Manley, K.Bantawa, Kent State University, Kent, USA A.Knezevic, M.Korolija, M. Mekterovic and I.Supek, Rudjer Boskovic Institute, Zagreb, Croatia D.Sober, Catholic University, Washington DC M.Vanderhaeghen, College of Williams and Mary, Williamsburg, USA The CB/TAPS@MAMI collaboration

34. The GDH collaboration J.Ahrens 9,S.Altieri 15,16,J.R.M.Annand 6,G.Anton 3,H.-J.Arends 9,K.Aulenbacher 9,R.Beck 9, C.Bradtke 1,A.Braghieri 15,N.Degrande 4, N.d'Hose 5, H.Dutz 2, S.Goertz 1, P.Grabmayr 17, K.Hansen 8, J.Harmsen 1, S.Hasegawa 13,T.Hasegawa 11, E.Heid 9, K.Helbing 3, H.Holvoet 4, L.VanHoorebeke 4, N.Horikawa 14,T.Iwata 13, P.Jennewein 9, T.Kageya 14, B.Kiel 2,F.Klein 2, R.Kondratiev 12,K.Kossert 7,J.Krimmer 17,M.Lang 9,B.Lannoy 4,R.Leukel 9,V.Lisin 12,T.Matsuda 11,J.C. McGeorge 6,A.Meier 1,D.Menze 2,W.Meyer 1,T.Michel 3,J.Naumann 3, A.Panzeri 15,16, P.Pedroni 15,T.Pinelli 15,16,I.Preobrajenski 9,12,E.Radtke 1,E.Reichert 10,G.Reicherz 1,Ch.Rohlof 2, G.Rosner 6, D.Ryckbosch 4,F.Sadiq 6,M.Sauer 17,B.Schoch 2, M.Schumacher 7, B.Seitz 7, T.Speckner 3,M.Steigerwald 9, N.Takabayashi 13, G.Tamas 9, A.Thomas 9, R.van de Vyver 4, A.Wakai 14, W.Weihofen 7, F.Wissmann 7, F.Zapadtka 7, G.Zeitler 3 1 Institute of Experimental Physics, Ruhr-University, Bochum, Germany 2 Physics Institute, University of Bonn, Germany 3 Physics Institute, University of Erlangen-Nuernberg, Erlangen, Germany 4 Nuclear Physics Laboratory, Gent, Belgium 5 CEA Saclay, DSM/DAPNIA/SPhN, Gif-sur-Yvette, France 6 Department of Physics & Astronomy, University of Glasgow, U.K. 7 II.Physics Institute, University of Goettingen, Germany 8 Department of Physics, University of Lund, Sweden 9,10 Institute of Nucl. Physics and Inst. of Physics, University of Mainz, Germany 11 Faculty of Engineering, Miyazaki University, Miyazaki, Japan 12 INR, Academy of Science, Moscow, Russia 13,14 Department of Physics and CIRSE, Nagoya University, Nagoya, Japan 15,16 INFN Sezione di Pavia and Dept. of Nucl. Physics of the University, Pavia, Italy 17 Physics Institute, University of Tuebingen, Germany

36. A. Fix and H. Arenhövel, MKPH-T-05-1

43.  Photoproduction DSG E MAID2003

45. Assafiri et al., PRL 90 (2003) 222001

46. A2 Time-Schedule for parallel running in the years 2006-2007 -12/2005 Tagger upgrade, Magnet installation 01/2006Calibration and commissioning Tagger, test goniometer 04/2006Detector tests with H2-Target and Crystal Ball 04/2006Experiments with unpolarized Targets:total: 3805h MAMI BA2-7/03 3 He 885MeV  mesic nuclei300h MAMI CA2-2/05H 2 1500MeVrare  -decay950h MAMI CA2-4/05H 2 1500MeVMagnetic moment S 11(550h)* MAMI CA2-1/05H 2 1500MeVin medium  (100h)* MAMI BA2-5/05H 2 885MeVRecoil (400h)* MAMI CA2-5/05H 2 1500MeVRecoil (500h)* MAMI CA2-3/05H 2 1500MeVrare  ´-decay700h MAMI CA2-4/05D 2 1500MeVMagnetic moment S 11 550h MAMI CA2-10/05D 2 1500MeV  -Prod. (200h)* MAMI CA2-1/05D 2 1500MeVin medium  (100h)* MAMI CA2-11/05D 2 1500MeVd  d  (350h)* MAMI CA2-6/05 16 O, C1500MeVAsym. 2 proton205h MAMI CA2-1/05 12 C1500MeVin medium  100h MAMI CA2-1/05 nat Ca1500MeVin medium  100h MAMI CA2-1/05 93 Nb1500MeVin medium  400h MAMI CA2-1/05 nat Pb1500MeVin medium  500h 05/20072 month for installation frozen spin target, CB on rails 07/2007Experiments with polarized Targets:total: 885h in 2007 MAMI BA2-7/05H-But. 885MeVGDH proton250h MAMI CA2-7/05H-But.1500MeVGDH proton (250h)* MAMI CA2-8/05H-But.1500MeVG-Asymmetry635h 2008 MAMI BA2-9/05D-But. 885MeVGDH neutron350h MAMI CA2-9/05D-But.1500MeVGDH neutron (450h)* MAMI CA2-10/05D-But.1500MeVE-Observ.  -Prod.700h MAMI CA2-11/05D-But.1500MeV ,G,E-Observ.,  600h MAMI CA2-12/05D-But.1500MeVTransvers. PT Coherent  0 1200h ( )* Experiments in frames can be done parallel