Comparison between uu and dd productions by the p - ++ and + 0 reactions at forward angles at E = GeV Oct/5/2015 RCNP, Osaka University Hideki Kohri 1 Contents SPring-8 LEPS facility New pion data Development of polarized HD target Development of LEPS2 beam line Summary 2 SPring-8 LEPS facility 3 Electron storage ring 8 GeV electron beam Diameter 457 m RF 508 MHz 1bunch spread is within 12 psec Beam Current = 100 mA 120 km distant from Osaka Super Photon ring GeV 4 SPring-8 beamline map LEPS 5 LEPS facility LEPS experiment started in 2000 b) Laser hutch a) SPring-8 SR ring c) Experimental hutch Inverse Compton -ray Laser light 8 GeV electron Recoil electron Tagging counter Collision Energy spectrum of BCS photons Bremsstrahlung Backward-Compton scattering 36m 70m SSD + Sc hodoscope ScFi + Sc hodoscope Beam intensity < 2.5 x 10 6 for E = GeV (355 nm laser) < 3.0 x 10 5 for E = GeV (266 nm laser) 6 LEPS detector setup 1m1m TOF wall MWDC 2 MWDC 3 MWDC 1 Dipole Magnet (0.7 T) Target Silicon Vertex Detector Aerogel Cerenkov (n=1.03) Start counter LEPS detector was optimized to detect meson decaying to K + K - at forward angles for removing e + e - BG also removed pions 7 LEPS publication Strangeness p -> K + , p -> K + 0 R.G.T. Zegers et al. Phys. Rev. Lett. 91 (2003) p -> K + , p -> K + 0 M. Sumihama et al. Phys. Rev. C 73 (2006) n -> K + - H. Kohri et al. Phys. Rev. Lett. 97 (2006) p -> K + K. Hicks et al. Phys. Rev. C 76 (2007) (R) p -> K + - (1385) K. Hicks et al. Phys. Rev. Lett. 102 (2009) p -> K + (1405), (1385) M. Niiyama et al. Phys. Rev. C 78 (2008) p -> K + (1520) N. Muramatsu et al. Phys. Rev. Lett. 103 (2009) p -> K + (1520) H. Kohri et al. Phys. Rev. Lett. 104 (2010) p -> K *0 + S.H. Hwang et al. Phys. Rev. Lett. 108 (2012) d -> K + - X A.O. Tokiyasu et al. Phys. Lett. B 728 (2014) 616 meson meson production on Li, C, Al, Cu T. Ishikawa et al. Phys. Lett. B 608 (2005) 215 p p T. Mibe et al. Phys. Rev. Lett. 95 (2005) d -> d W.C. Chang et al. Phys. Lett. B 658 (2008) 209 n -> n W.C. Chang et al. Phys. Lett. B 684 (2010) 6 p -> p, n -> n W.C. Chang et al. Phys Rev. C 82 (2010) Pseudoscaler p -> 0 p M. Sumihama et al. Phys. Lett B 657 (2007) 32 p -> p M. Sumihama et al. Phys. Rev. C 80 (2009) (R) p -> p, p Y. Morino et al. Prog. Theor. Exp. Phys. (2015) 013D01 Exotic Pentaquark search T. Nakano et al. Phys. Rev. Lett. 91 (2003) Pentaquark search T. Nakano et al. Phys. Rev. C 79 (2009) LEPS publication Strangeness p -> K + , p -> K + 0 R.G.T. Zegers et al. Phys. Rev. Lett. 91 (2003) p -> K + , p -> K + 0 M. Sumihama et al. Phys. Rev. C 73 (2006) n -> K + - H. Kohri et al. Phys. Rev. Lett. 97 (2006) p -> K + K. Hicks et al. Phys. Rev. C 76 (2007) (R) p -> K + - (1385) K. Hicks et al. Phys. Rev. Lett. 102 (2009) p -> K + (1405), (1385) M. Niiyama et al. Phys. Rev. C 78 (2008) p -> K + (1520) N. Muramatsu et al. Phys. Rev. Lett. 103 (2009) p -> K + (1520) H. Kohri et al. Phys. Rev. Lett. 104 (2010) p -> K *0 + S.H. Hwang et al. Phys. Rev. Lett. 108 (2012) d -> K + - X A.O. Tokiyasu et al. Phys. Lett. B 728 (2014) 616 meson meson production on Li, C, Al, Cu T. Ishikawa et al. Phys. Lett. B 608 (2005) 215 p p T. Mibe et al. Phys. Rev. Lett. 95 (2005) d -> d W.C. Chang et al. Phys. Lett. B 658 (2008) 209 n -> n W.C. Chang et al. Phys. Lett. B 684 (2010) 6 p -> p, n -> n W.C. Chang et al. Phys Rev. C 82 (2010) Pseudoscaler p -> 0 p M. Sumihama et al. Phys. Lett B 657 (2007) 32 p -> p M. Sumihama et al. Phys. Rev. C 80 (2009) (R) p -> p, p Y. Morino et al. Prog. Theor. Exp. Phys. (2015) 013D01 Exotic Pentaquark search T. Nakano et al. Phys. Rev. Lett. 91 (2003) Pentaquark search T. Nakano et al. Phys. Rev. C 79 (2009) New pion data 10 New LEPS detector setup for taking pion data 1m1m TOF wall MWDC 2 MWDC 3 MWDC 1 Dipole Magnet (0.7 T) Target Silicon Vertex Detector Start counter LEPS detector was optimized to detect meson decaying to K + K - at forward angles Aerogel Cerenkov counter was removed 11 High momentum data taken in 2007 p( , + )X p( , - )X E = GeV 0.7 3 - ++ : 1 + 0 * -> 3 - ++ : 4 + 0 Resonance effect t-channel LEPS energy No d /dcos Physics motivation of reactions at E = GeV Low energy E =1.5 GeV Missing resonance search s- channel High energy E =3.0 GeV Precision of isospin rule is checked. Any other effect ? t- channel p p p p N*N* Isospin=1 Isospin=2 ( + 0 )/ ( - ++ ) = 1/3 ( + 0 )/ ( - ++ ) = 4/3 ( + 0 )/ ( - ++ ) = 1/3 ( + 0 )/ ( - ++ ) = 3 15 ( )/ ( ) ratio expected from Clebsch-Gordan coefficients I=1 ( or ) exchange in the t-channel should be dominant at forward angles. Deviation from 1/3 might suggest I=2 exotic meson exchange. Dominant 16 High momentum data taken in 2007 p( , + )X p( , - )X E = GeV 0.7