Photoproduction of charged pions on deuteron Yuncheng HAN(韩运成) for the NKS2 Collaboration School of Nuclear Science and Technology, Lanzhou University Department of Physics, Tohoku University A workshop on Hadron Physics@LZU, Lanzhou 7/31- 8/1, 2009

A workshop on hadron physics@LZU, Lanzhou Collaboration List Department of Nuclear Science, Lanzhou University, China , Y.C. Han , T.S. Wang Department of Physics, Tohoku University, Japan N. Chiga, Y. Fujii, T.Fujibayashi, K. Futatsukawa, O. Hashimoto, K. Hosomi, A. Iguchi, H. Kanda, M. Kaneta, M. Kawai, D. Kawama, T. Kawasaki, S. Kiyokawa, T. Koike, Y. Ma, K. Maeda, N. Maruyama, M. Matsuzawa, A. Matsumura, M. Mimori, Y. Miyagi, K. Miwa, S.N. Nakamura, Y. Okayasu, T. Otani, K. Shirotori, H. Tamura, N. Terada, K. Tsukada, T. Yamamoto, K. Yokota Laboratory of Nuclear Science, Tohoku University K. Hirose, T. Ishikawa, H. Shimizu, K. Suzuki, T. Tamae, H. Yamazaki Ichinoseki National College of Technology O. Konno Department of Electrical and Electric Engineering, Akita University, A. Sasaki 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

A workshop on hadron physics@LZU, Lanzhou Content Introduction Experimental setups Analysis and results Summary 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Study of pion photoproduction Photoproduction on proton: Locate and identify pion nucleon resonances. Photoproduction on neutron (deuteron): Elementary production amplitude, isospin symmetry. Photoproduction on nuclei: Modifications of the resonance excitation and their subsequent propagation and decay, brought by the nuclear medium. 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Motivation: gd→p-pp, esp. NQF process Quasi-Free process Non Quasi-Free process 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Motivation: Study of gd→npp+p- reaction D++ (uuu) D- (ddd) 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Tagged Photon Beam at LNS-Tohoku Neutral Kaon Spectrometer 2 200 MeV electron beam from LINAC Sweep magnet Photon tagging system Stretcher-Booster Ring Emax=1.2 GeV Radiator 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

A workshop on hadron physics@LZU, Lanzhou Photon Tagging System Photon beam Electron beam on carbon fiber Tagged by scattering electron E=0.8-1.1 GeV from 1.2 GeV mood electron beam mode 6 MeV coverage per tagging counter Tagger Backup Tagger Finger Radiator 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

A workshop on hadron physics@LZU, Lanzhou NKS2 Setup Electron Veto Counter (EV) 680 Dipole Magnet Inner Hodoscope (IH) & Outer Hodoscope (OH) 20 cm LD2Target Photon beam 1 m Cylindrical Drift Chamber (CDC) & Straw Drift Chamber (SDC) Photon beam 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

A workshop on hadron physics@LZU, Lanzhou Analysis Time selection Track selection Vertex position Particle Identify Channel selection for gd→p-pp and gd→ np p+p- → suppress accidental coincidence → suppress noisy of Drift Chamber → target region select 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Channel selection of gd→(p-pp)3Tr For reconstructed gd→p-pX mass Mmissing , 0.8<Mmissing<1.1 (GeV/c2); For reconstructed gX→p-pp mass Mtarget , 1.75<Mtarget<2.1 (GeV/c2); 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Channel selection of gd→npp+p- Px<0.2 GeV/c: quasi-free; Px>0.3 GeV/c: non-quasi-free process; mx ~ mpeak±3s; 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Sub-channel fitting for gd→(npp+p-)NQF 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Calculation and various parameters The cross section is obtained as, Y is the yield, Ng is the number of photon, Nt is the effective deuteron target thickness, εDAQ is efficiency of data acquisition system, εaccptance is the acceptance decided by simulation. εtrack is the efficiency of track reconstructing. 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Cross section of gd→(p-pp)QF Author Eg Bin/ MeV Benz 100 Scheffler 25 Hirose 24 This work 6 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Cross section of gd→(p-pp)NQF Errors are 10% 300 MeV 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Eg calibration by gd→(p-pp)3Tr 4-momentum conservation: Lg=Lp+Lp1+Lp2-Ld HAN Yun-Cheng, Wang Tie-Shan, et. al., Chin. Phys. C, Accepted 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Comparison of s(gd→ D++D-) 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

A workshop on hadron physics@LZU, Lanzhou Summary Photoproduction gd→p-pp and gd→npp+p- are studied with tagged photons by using NKS2@LNS-Tohoku. s (gd→(p-pp)QF) agrees well with the previous obtained data. we get s (gd→(p-pp)NQF),and used to calibrate Eg; s (gd→D++D- ) are smaller than the previous obtained data and theory study; In the future, differential cross sections will be studied, and experiments in the lower energy region are scheduled. 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou

Thanks for your attention! 7/31- 8/1, 2009 A workshop on hadron physics@LZU, Lanzhou