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N* spectroscopy with meson photoproduction reactions

N* spectroscopy with meson photoproduction reactions. Hiroyuki Kamano (RCNP, Osaka U.). Collaborators ： T.-S. H. Lee （ Argonne Natl. Lab. ） S.X. Nakamura （ Osaka U. ） T. Sato （ Osaka U. ）. 東北 大 ELPH 研究会「 GeV 領域光子で探るメソン生成反応の物理」 Feb. 20-21, 2014. qqc (I=0) [q = u or d].

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N* spectroscopy with meson photoproduction reactions

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  1. N* spectroscopy withmeson photoproduction reactions Hiroyuki Kamano (RCNP, Osaka U.) Collaborators： T.-S. H. Lee（Argonne Natl. Lab.） S.X. Nakamura（Osaka U.） T. Sato（Osaka U.） 東北大ELPH研究会「GeV領域光子で探るメソン生成反応の物理」 Feb. 20-21, 2014

  2. qqc (I=0) [q = u or d] Baryon Spectroscopy: Understanding nature of baryons and their excitations Isospin qqc (I=1) [q = u or d] qqq (I=1/2) [q = u or d] qsc (I=1/2) [q = u or d] ssc (I=0) Mass, width, spin, parity …? Internal structure? How produced in reaction processes? How interact with other particles? qss (I=1/2) [q = u or d] qcc (I=1/2) [q = u or d] sss (I=0) qqb (I=0) [q = u or d] qqs (I=1) [q = u or d] qqq (I=3/2) [q = u or d] qqb (I=1) [q = u or d] qsb (I=1/2) [q = u or d] ssb (I=0) Baryons PDG (2012): http://pdg.lbl.gov qqs (I=0) [q = u or d]

  3. Meson photoproduction reactions in N*, Δ* resonance region πN, ηN, ππN KΛ, KΣ, ωN, … γ . Region our model covers . “Δ-region” Je.m. N . N*, Δ* • Study electromagnetic • interactions of N*、Δ* • Used also for establishing N*, Δ* • mass spectrum and searching for • new N*, Δ* resonances γp reaction total cross section in N*、Δ* region （Database is provided by Kanda-san）

  4. Approaches to N* spectroscopy Reaction Data JLab, ELSA, MAMI, SPring-8, ELPH,… Analysis based on reaction theory N* spectroscopy with multichannel unitary reaction models has made a significant progress. • Multichannel unitary condition: Mass, width, form factors, etc of N* & Δ* QCD-inspired Hadron Models Lattice QCD • Ensures conservation of probability. • Defines analytic structure (branch points, • cuts) of the amplitudes in complex-E plane. QCD ANL-Osaka/EBAC-JLab, Bonn-Gatchina, Carnegie Mellon-Berkely, Dubna-Mainz-Taipei, VPI/GWUGeorge, Giessen, Juelich, Karlsruhe-Helsinki, … Constituent quark models Soliton models Holographic QCD etc Our approach !!

  5. Unitary multichannel reaction model Dynamical coupled-channels model [Matsuyama, Sato, Lee, Phys. Rep. 439(2007)193] channel coupling effect e.g.）πN scattering η N π N K Λ π N π N V … Summing up all possible transitions between reaction channels in the intermediate processes !! ＋ ＝ ＋ ＋

  6. ANL-Osaka dynamical coupled-channels analysisof meson production reactions Physical N*s will be a “mixture” of the two pictures: meson cloud core (bare) baryon meson Transition potential t-channel contact u-channel s-channel p, r, s, w,.. Exchange potential N N, D Bare N* states Exchange potentials Formation of hadron resonances Bare N* states N*bare ＋ ＋ ＋ ＝ bare N* Bare N* states： Corresponding to N* states defined in static hadron models excluding meson-baryon continuums ＋ ＝ ＋ ＋

  7. Extraction of baryon resonances via comprehensive analysis of meson production reactions Construct the reaction model by making a comprehensive analysis of πN  πN, ππN, ηN, KΛ, KΣ, ωN,… γ(*)N  πN, ππN, ηN, KΛ, KΣ, ωN,… Mass spectrum Making analytic continuation of amplitudes to complex E-plane (Suzuki, Sato, Lee PRC79(2009)025205; PRC82(2010)045206) DCS π+ p  K+ Σ+ poles of amplitude= baryon resonance!! Decay width Ours PDG 4* PDG 3* • mass、width pole posiiton • coupling constants •  “(residues)1/2” at the pole P

  8. Our analyses of meson production reactions Fully combinedanalysis of pN, gN N , hN , KL, KSreactions !! 2010 – 2013 (ANL-Osaka) 8channels (gN,pN,hN,pD,rN,sN,KL,KS) < 2.3 GeV < 2.1 GeV < 2.1 GeV < 2.1 GeV < 2.1 GeV < 2.1 GeV 2006 – 2009 (EBAC/JLab) 6channels (gN,pN,hN,pD,rN,sN) < 2 GeV < 1.6 GeV < 2 GeV ― ― ― • # of coupled channels • p  N • gp N • phN • gphp • ppKL, KS • gpK+L, KS Julia-Diaz, Lee, Matsuyama, Sato, PRC76 (2007) 065201; Julia-Diaz, et al., PRC77 (2008) 045205 HK, Nakamura, Lee, Sato PRC88 (2013) 035209

  9. Database for ANL-Osaka DCC analysis πN  πN PWA from SAID πp  ηN, KΛ, KΣ observables Pseudoscalar meson photoproductions have 1 + 15 observables !! unpolarized diff. crs. sec. single pol. beam-target beam-recoil target-recoil “(Over-) complete” experiments has been achieved by CLAS for KΛand KΣ photoproductions !!! HK, Nakamura, Lee, Sato PRC88 (2013) 035209 22,348 data ofunpolarized& polarized observables to fit !! γp πN, ηp, KΛ, KΣ observables

  10. γ p  π0 p reaction Differential cross section (W = 1.08-2.1 GeV) 1.9 GeV 1.6 GeV previous 6ch DCC-analysis (fitted to gN pNdata onlyup to W = 1.6 GeV) [Julia-Diaz et al., PRC77 (2008) 045205] 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209]

  11. γ p  π0 p reaction (2/3) Σ Note: In computing polarization obs. of pseudoscalar-meson photoproductions, we followed convention defined in Sandorfi, Hoblit, Kamano, Lee, J. Phys. G38 (2011) 053001. (See arXiv:1108.5411 for comparison of conventions used in different analysis groups.)

  12. γ p  π0 p reaction (3/3) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] P H T G hat E

  13. Mass spectrum

  14. Transition form factors and baryon structure Measurement of p(e,e’π)N & p(e,e’ππ)N for 5 < Q2 < 10 (GeV/c)2.  JLab CLAS12experiment (E12-09-003) e’ e γ* “partonic” picture “hadronic” picture N meson clouds baryon N*, Δ* meson ？ “bare”baryon g* (q2 = -Q2) q Q2: large Q2: small N N*, Δ* N-N* electromagnetic transition form facctor How effective d.o.f.’s describing baryon change with Q2 ?

  15. Transition form factors and baryon structure N D (1232) M1 transition form factor Transverse (transition) charge densities Tiator et al., EPJST 198 (2011) 141 light：＋charge dark：０or －charge proton  proton Lattice QCD Alexandrou et al., PRD83 (2011) 014501 by [fm] by [fm] polarized in x-dir. unpolarized density bx [fm] bx [fm] proton  N*(1440)[Roper resonance] Δ(1232) at low Q2 Full Bare Julia-Diaz et al, PRC75 015205 (2007) unpolarized density polarized in x-dir.

  16. What we expect ELPH? • Establish N*, Δ* spectrum in s1/2 = 1450 - 1750 MeV • The data we expect: • New N*, Δ* could exist behind large N* (1535) 1/2-、N*(1650) 1/2-、 • N*(1520) 3/2-resonances !! • (Many channels open in 1.6-1.7 GeV region) ππN (~ 1220 MeV)、πηN(~ 1620 MeV)、 ηN (~ 1490 MeV)、KΛ (~ 1610 MeV)、 KΣ (~ 1680 MeV)、ωN (~ 1720 MeV) Δ(1600) 3/2+ : Roper-likestate of Δ baryon mass is still uncertain (1450-1700 MeV) N(1685) ?? : Seen in γd (ηn) p Double meson productions &Deuteron(neutron) target reactions

  17. Our tasks • Reducing computing time • Extension to deuteron-target reactions （Computing time for double meson productions） （Computing time for singlemeson productions） π, η, K, ππ,… γ = O(101) d Computation of cross section O(106-107) times are needed in χ2 -fitting. + …

  18. γ “n”  π- p dσ/dΩ Σ P T VERY PRELIMINARY !!

  19. γ “n”  π0 n Σ dσ/dΩ VERY PRELIMINARY !!

  20. γ “n”  ηn dσ/dΩ VERY PRELIMINARY !! Σ

  21. Predicted results for γ “n”  K0Λ ALL observables @ W = 1.8 GeV Sensitive to F17 wave? VERY PRELIMINARY !!

  22. Double-pion production cross sections(current situation) Predicted πp  ππN cross sections πNπΔ πNπΔ, ρN πNπΔ, ρN,σN πNπΔ, σN πNπΔ, ρN 8ch. model [HK, PRC88 (2013) 045208] 6ch. model [HK, Julia-Diaz, Lee, Matsuyama, Sato, PRC79 (2008) 025206]

  23. Double-pion production cross sections(current situation) Predicted γp ππN cross sections γNπΔ, σN γNπΔ, ρN,σN 8ch. model [HK, Nakamura, Lee, Sato PRC88 (2013) 035209] 6ch. model [HK, Julia-Diaz, Lee, Matsuyama, Sato, PRC80 (2009) 065203] γNπΔ, ρN

  24. What we expect LEPS/LEPS2 ? • Establish high-mass N*, Δ* mass spectrum • The data we expect & our tasks • Poorly established • Very large width Approaches based on reaction theory • will become more important. • In the future, we aim at establishing N*, Δ* spectrum up to s1/2 = 2.5 GeV • that can access with LEPS/LEPS2. Differential cross section and polarizations of γN η’N, ΦN, K*Y, KΣ*,… Our tasks： Reducing computation time treatment of 4-body channel（πππN）（ρΔchannel）

  25. Other topics • meson productions with electron beam?? e+d reactions are necessary for extracting Q2 dependence of neutron target n-N* transition form factors. Transition form factors are crucial not only for N* structure study, but also for neutrino-induced reactions !! Collaboration@J-PARC Branch of KEK Theory Center & 新学術領域研究「ニュートリノフロンティアの融合と進化」C02班 Construction of unified neutrino reaction model describing overlapping regions between QE, RES, and DISregions !! http://nuint.kek.jp Y. Hayato (ICRR, U. of Tokyo), M. Hirai (Tokyo U.of Sci.) H. Kamano (RCNP, Osaka U.), S. Kumano (KEK) S. Nakamura (YITP, Kyoto U.), K. Saito (Tokyo U. of Sci.) M. Sakuda (Okayama U.), T. Sato (Osaka U.) [ arXiv:1303.6032] QE region RES region DIS region CP phase & mass hierarchy studies with atmospheric exp. T2K

  26. back up

  27. γ p  π+n reaction (1/3) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] DCS Σ

  28. γ p  π+ n reaction (2/3) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] P T

  29. γ p  π+ n reaction (3/3) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] hat E G H

  30. γ p  ηp reaction (1/2) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] DCS

  31. γ p  ηp reaction (2/2) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] T Σ

  32. γ p  K+ Λ reaction (1/2) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] Σ DCS P

  33. γ p  K+ Λ reaction (2/2) 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] T Cx’ Cz’ Ox’ Oz’

  34. γ p  K+ Σ0 reaction 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] DCS P Cx’ Cz’ Σ

  35. γ p  K0 Σ+ reaction 8ch DCC-analysis [HK, Nakamura, Lee, Sato, PRC88 (2013) 035209] DCS P Σ

  36. 質量スペクトル

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