1. Workshop on “Extractions and interpretations of hadron resonances and multi-meson production reactions with 12 GeV upgrade”, May 27-28, 2010 Cascade Baryons: Spectrum and production in photon-nucleon reactions Yongseok Oh (Kyungpook National University, Korea)

2. 2010-05-27 EBAC Workshop, JLab 2 Overview

3. 2010-05-27 EBAC Workshop, JLab 3 1. Introduction

4. 2010-05-27 EBAC Workshop, JLab 4 Baryons in SU(3) Baryon octetBaryon decuplet

5. 2010-05-27 EBAC Workshop, JLab 5 1. Introduction

6. 2010-05-27 EBAC Workshop, JLab 6  in PDG What do we know about  baryons? Particle Data Group (2008): 11  ’ s P is not directly measured

7. 2010-05-27 EBAC Workshop, JLab 7 1. Introduction

8. 2010-05-27 EBAC Workshop, JLab 8 Advantages Difficulties PDG 2008

9. 2010-05-27 EBAC Workshop, JLab 9 1. Introduction

10. 2010-05-27 EBAC Workshop, JLab 10 Experiments WA89 (CERN-SPS) EPJC, 11 (1999), hep-ex/0406077 1690

11. 2010-05-27 EBAC Workshop, JLab 11 CLAS@JLab PRC 71 (2005)PRC 76 (2007)

12. 2010-05-27 EBAC Workshop, JLab 12 Questions PDG 2008 The 3 rd lowest state CLAS: PRC 76 (2007)

13. 2010-05-27 EBAC Workshop, JLab 13 Classify the states as members of octet or decuplet Use spin-parity (if known) and Gell-Mann—Okubo mass relation Works before 1975: reviewed by Samlos, Goldberg, Meadows RMP 46 (1974) Recent work along this line Guzey & Polyakov, hep-ph/0512355 (2005) No dynamics Direct extension of the classification in the quark model Hadron models for  baryons

14. 2010-05-27 EBAC Workshop, JLab 14 Nonrelativistic quark model Chao, Isgur, Karl PRD 23 (1981) from S. Capstick The 3 rd lowest state at 1695 MeV? The 3 rd lowest state at 1695 MeV?

15. 2010-05-27 EBAC Workshop, JLab 15 Relativistic quark model Capstick, Isgur PRD 34 (1986) from S. Capstick The 3 rd lowest state ?

16. 2010-05-27 EBAC Workshop, JLab 16 One-boson exchange model Glozman, Riska Phys. Rep 268 (1996) from S. Capstick The 3 rd lowest state ?

17. 2010-05-27 EBAC Workshop, JLab 17

18. 2010-05-27 EBAC Workshop, JLab 18 The 3 rd lowest state ? from J.L. Goity

19. 2010-05-27 EBAC Workshop, JLab 19 Summary QM (Pervin, Roberts) 1325 1891 2014 PRC 75 1520 1934 2020 1725 1811 1759 1826 1820 (expt.) 1320 (expt.) 1530 (expt.) : the 3 rd lowest state

20. 2010-05-27 EBAC Workshop, JLab 20 Summary Highly model-dependent !

21. 2010-05-27 EBAC Workshop, JLab 21 Skyrme model bound kaon SU(3) is badly broken Treat light flavors and strangeness on the different footing L = L SU(2) + L K/K* Soliton provides background potential which traps K/K* (or heavy) meson Bound state approach (Callan, Klebanov)

22. 2010-05-27 EBAC Workshop, JLab 22 Bound state model 270 MeV energy difference Includes parameters They should be computed with a given Lagrangian (dynamics). Or fix them to known masses and then predict. Mass formula

23. 2010-05-27 EBAC Workshop, JLab 23 Hyperon spectrum (expt.) 289 MeV 290 MeV 285 MeV positive parity negative parity parity undetermined

24. 2010-05-27 EBAC Workshop, JLab 24 Hyperon spectrum (Skyrme model) YO, PRD 75 (2007) spin-parity Recently confirmed by COSY PRL 96 (2006) High precision experiments are required!  ’s would be discovered in future.

25. 2010-05-27 EBAC Workshop, JLab 25 More comments Other approaches

26. 2010-05-27 EBAC Workshop, JLab 26

27. 2010-05-27 EBAC Workshop, JLab 27 Forbidden or suppressed mechanisms

28. 2010-05-27 EBAC Workshop, JLab 28 Considered diagrams + exchanged diagrams q 1 q 2

29. 2010-05-27 EBAC Workshop, JLab 29 Methods

30. 2010-05-27 EBAC Workshop, JLab 30 Intermediate hyperons Particle Data Group Decay widths (and couplings) are in a very wide range. No information for the other couplings.

31. 2010-05-27 EBAC Workshop, JLab 31 Total cross section CLAS: PRC 76 (2007)

32. 2010-05-27 EBAC Workshop, JLab 32 Differential cross sections

33. 2010-05-27 EBAC Workshop, JLab 33 No structure

34. 2010-05-27 EBAC Workshop, JLab 34 NOT from a resonance Needs higher-mass resonances More works are needed! Needs higher-mass resonances More works are needed!

35. 2010-05-27 EBAC Workshop, JLab 35 4. Outlook

36. 2010-05-27 EBAC Workshop, JLab 36 Preliminary