Dynamical coupled-channels study of hadron resonances and strangeness production

Hiroyuki Kamano(RCNP, Osaka U.)

in collaboration withB. Julia-Diaz (Barcelona U.), T.-S. H. Lee (Argonne),A. Matsuyama (Shizuoka U.), S. Nakamura (JLab),

T. Sato (Osaka U./KEK), N. Suzuki (Osaka U.)

Workshop on “Future Prospects of Hadron Physics at J-PARC and Large Scale Computational Physics”, Tokai, Feb. 9-11, 2012

Outline

Results of 5-year project on nucleon resonance

extraction at EBAC@JLab

Theory projects for strangeness production

reactions on the nucleons and nuclei

N* spectroscopy : Physics of broad & overlapped resonances

N* : 1440, 1520, 1535, 1650, 1675, 1680, ...D : 1600, 1620, 1700, 1750, 1900, …

Δ (1232)

Width: a few hundred MeV. Resonances are highly overlapped　　 in energy except D(1232).

Width: ~10 keV to ~10 MeV Each resonance peak is clearly separated.

Since the late 90s, huge amount of high precision data of meson photo-production reactions on the nucleon target has been reported from electron/photon beam facilities.

JLab, MAMI, ELSA, GRAAL, LEPS/SPring-8, …

Experimental developments

From E. Pasyuk’s talk at Hall-B/EBAC meeting

Total cross sections of meson photoproductions

Opens a great opportunity to make quantitative study of the N* states !!

Objectives and goals:

Through the comprehensive analysis of world data of pN, gN, N(e,e’) reactions,

Determine N* spectrum (pole masses)

Extract N* form factors

(e.g., N-N* e.m. transition form factors)

Provide reaction mechanism information necessary for interpreting N* spectrum, structures and dynamical origins

Research project at Excited Baryon Analysis Center (EBAC) of Jefferson Lab

N* properties

QCD

Lattice QCDHadron Models

Dynamical Coupled-Channels Analysis

Reaction Data

“Dynamical coupled-channels model of meson production reactions”

A. Matsuyama, T. Sato, T.-S.H. Lee Phys. Rep. 439 (2007) 193

Partial wave (LSJ) amplitudes of a b reaction:

Reaction channels:

Transition Potentials:

coupled-channels effect

Exchange potentials bare N* states

For details see Matsuyama, Sato, Lee, Phys. Rep. 439,193 (2007)

Z-diagrams

Dynamical coupled-channels (DCC) model for meson production reactions

Meson-Baryon Green functions

Stable channels Quasi 2-body channels

N p

Dp

D

ppp

r, s r, s

N N

p, r, s, w,..

N N, D

s-channel u-channel t-channel contact

Exchange potentials

Z-diagrams

Bare N* statesN*bare

Dp

N p

p

DDNp

r, s

Can be related with the hadron states of the static hadron structure calculations. (quark models etc.)

core

meson cloud

meson

baryon

Physical N*s will be a “mixture” of the two pictures:

DCC analysis @ EBAC (2006-2009)

p N p N : Analyzed to construct a hadronic part of the model up to W = 2 GeVJulia-Diaz, Lee, Matsuyama, Sato, PRC76 065201 (2007)

p N h N : Analyzed to construct a hadronic part of the model up to W = 2 GeVDurand, Julia-Diaz, Lee, Saghai, Sato, PRC78 025204 (2008)

p N p p N : First fully dynamical coupled-channels calculation up to W = 2 GeVKamano, Julia-Diaz, Lee, Matsuyama, Sato, PRC79 025206 (2009)

g(*) N p N : Analyzed to construct a E.M. part of the model up to W = 1.6 GeV and Q2 = 1.5 GeV2

(photoproduction) Julia-Diaz, Lee, Matsuyama, Sato, Smith, PRC77 045205 (2008) (electroproduction) Julia-Diaz, Kamano, Lee, Matsuyama, Sato, Suzuki, PRC80 025207 (2009)

g N p p N : First fully dynamical coupled-channels calculation up to W = 1.5 GeV Kamano, Julia-Diaz, Lee, Matsuyama, Sato, PRC80 065203 (2009)

Extraction of N* pole positions & new interpretation on the dynamical origin of P11 resonancesSuzuki, Julia-Diaz, Kamano, Lee, Matsuyama, Sato, PRL104 065203 (2010)

Stability and model dependence of P11 resonance poles extracted from pi N pi N dataKamano, Nakamura, Lee, Sato, PRC81 065207 (2010)

Extraction of gN N* electromagnetic transition form factorsSuzuki, Sato, Lee, PRC79 025205 (2009); PRC82 045206 (2010)

Hadronic part

Electromagnetic part

Extraction of N* parameters

pN, hN, ppN (pD, rN, sN) coupled-channelscalculations were performed.

Dynamical coupled-channels effect on N* spectrum

Pole positions and dynamical origin of P11 resonances

Suzuki, Julia-Diaz, Kamano, Lee, Matsuyama, Sato, PRL104 065203 (2010)

pole A: pD unphys. sheetpole B: pD phys. sheet

Dynamical Coupled-Channels analysis (current status)

pp pN

gp pN

p-p hn

gp hp

pp KL, KS

gp KL, KS

2006 ~ 2009

5 channels (pN,hN,pD,rN,sN)

< 2 GeV

< 1.6 GeV

< 2 GeV

―

―

―

2010 ~

7 channels (pN,hN,pD,rN,sN,KL,KS)

< 2.1 GeV

< 2 GeV

< 2 GeV

< 2 GeV

< 2.2 GeV

< 2.2 GeV

# of coupled channels

Fully combined analysis of gN , pN pN , hN , KL, KS reactions !!

Kamano, Nakamura, Lee, Sato, in preparation

Partial wave amplitudes of pi N scattering

Current model (fully combined analysis,

PRELIMINALY)

Previous model (fitted to pN pN data only)[PRC76 065201 (2007)]

Real part

Imaginary partKamano, Nakamura, Lee, Sato in preparation

KY production reactions

Preliminary!!

1732 MeV

1845 MeV

1985 MeV

2031 MeV

1757 MeV

1879 MeV

1966 MeV

2059 MeV

1792 MeV

1879 MeV

1966 MeV

2059 MeV

Kamano, Nakamura, Lee, Sato in preparation

1781 MeV 1785 MeV

Spectrum of N* resonancesReal parts of N* pole values

L2I 2J

PRELIMINARY!!

PDG Ours

N* with 3*, 4* 1816

N* with 1*, 2* 5PDG 4*

PDG 3*

Ours

Kamano, Nakamura, Lee, Sato in preparation

PRELIMINARY!!

Note: Some freedom exists on the definition of partial width from the residue of the amplitudes.

Width of N* resonances

Kamano, Nakamura, Lee, Sato in preparation

Theory Projects for Strangeness Production Reactions on the Nucleons and Nuclei

Participants: Hiroyuki Kamano (RCNP)T.-S. Harry Lee (Argonne Natl. Lab.)Yongseok Oh (Kyungpook U.)Toru Sato (Osaka U. / KEK)

Consistent description of production reactions of

hyperons and hypernuclei

1st discussion meeting:Dec. 4-10 2011 @ Kyungpook U., Korea

GOAL

1. Baryon spectroscopy of the strangeness sector

Extends DCC approach to analyze Y* production reactions and

establish L*, S*, and also X* spectroscopy.

KL*, S*

N

K, p, K

N, S, X

KL*, S*

N

K

X*M

B

(CLAS)L*, S*

N

K

X*

M

BN*, D*

KgIn photon-induced experiment, one has to analyze four-body production reactions.

2. Determination of YN and YY interactions via pion- and kaon-induced deuteron reactions

Y

p, K

N

K_

d

Yp

Y

K_

d

K

Y

K

Nd

p

Elemental meson-production amplitudes are provided fromour dynamical coupled-channels approach.

AY = L, S, X

p, KK_

A

ALL

K_

AL

L

K

3. Applications to production reactions of hypernuclei

Determined YN, YY interactions

Many-Body Theory

Properties of A Y,YY

back up

N, N*

Meson cloud effect in gamma N N* form factors

GM(Q2) for g N D (1232) transition

Note:Most of the available static hadron models give GM(Q2) close to “Bare” form factor.

Full

Bare

“Static” form factor fromDSE-model calculation.(C. Roberts et al)

A clue how to connect with static hadron models

“Bare” form factor determined fromour DCC analysis.

g p Roper e.m. transition

g N D(1232) form factors compared with Lattice QCD data

ours

Analysis Database

Pion-inducedreactions (purely strong reactions)

Photo-productionreactions

~ 28,000 data points to fit

The data have been taken by CLAS and will be published soon !!

Partial wave amplitudes of pi N scattering

Current model (fully combined analysis,

PRELIMINALY)

Previous model (fitted to pN pN data only)[PRC76 065201 (2007)]

Real part

Imaginary part

gamma p K+ Lambda, K+ Sigma0

Preliminary!!

1781 MeV 2041 MeV

Polarization observables are calculated using the formulae in Sandorfi, Hoblit, Kamano, Lee, J. Phys. G 38, 053001 (2011)

1785 MeV 1985 MeV

Kamano, Nakamura, Lee, Sato in preparation

Pion-nucleon elastic scattering

Current model

(fully combined analysis, preliminary)

Previous model (fitted to pN pN data only)[PRC76 065201 (2007)]

Target polarization

1234 MeV

1449 MeV

1678 MeV

1900 MeV

Angular distribution

Single pion photoproduction

Current model (fully combined analysis, preliminary)

Previous model (fitted to gN pN data up to 1.6 GeV) [PRC77 045205 (2008)]

Angular distribution Photon asymmetry

1137 MeV 1232 MeV

1334 MeV

1462 MeV 1527 MeV 1617 MeV

1729 MeV 1834 MeV 1958 MeV

1137 MeV 1232 MeV 1334 MeV

1462 MeV 1527 MeV 1617 MeV

1729 MeV 1834 MeV 1958 MeV

Preliminary!!Kamano, Nakamura, Lee, Sato in preparation

Data handled with the help of R. Arndt

pi N pi pi N reaction

Parameters used in the calculation are from pN pN analysis.

Kamano, Julia-Diaz, Lee, Matsuyama, Sato, PRC79 025206 (2009)

Full result

Phase spaceFull result

W (GeV)

s (m

b)

(# of pN ppN data) / (# of pN pN data) ~ 1200 / 24000

Above W = 1.5 GeV,

All pN ppN data were measured more than 3 decades ago.

No differential cross section data are available for quantitative fits (only the data without error bar exist).

Need help of hadron beam facilities such as J-PARC !!

Double pion photoproductionKamano, Julia-Diaz, Lee, Matsuyama, Sato, PRC80 065203 (2009)

Parameters used in the calculation are from pN pN & gN pN analyses.

Good description near threshold

Reasonable shape of invariant mass distributions

Above 1.5 GeV, the total cross sections of pp0p0 and pp+p-

overestimate the data.

1535 MeV

1674 MeV

1811 MeV

1930 MeV

1549 MeV

1657 MeV

1787 MeV

1896 MeV

Eta production reactions

Preliminary!!

Analyzed data up to W = 2 GeV. p- p h n data are selected following Durand et al. PRC78 025204.

Photon asymmetry

Single pion photoproduction

Current model (fully combined analysis, preliminary)

Previous model (fitted to gN pN data up to 1.6 GeV) [PRC77 045205 (2008)]

Angular distribution Photon asymmetry

Preliminary!!

1154 MeV 1232 MeV 1313 MeV

1416 MeV 1519 MeV 1617 MeV

1690 MeV 1798 MeV 1899 MeV

1154 MeV 1232 MeV 1313 MeV

1416 MeV 1519 MeV 1617 MeV

1690 MeV

1798 MeV 1899 MeV

pi N KY reactions

Preliminary!!Angular distribution Recoil polarization

1732 MeV

1845 MeV

1985 MeV

2031 MeV

1757 MeV

1879 MeV

1966 MeV

2059 MeV

1792 MeV

1879 MeV

1966 MeV

2059 MeV

1732 MeV

1845 MeV

1985 MeV

2031 MeV

1757 MeV

1879 MeV

1966 MeV

2059 MeV

1792 MeV

1879 MeV

1966 MeV

2059 MeV

Kamano, Nakamura, Lee, Sato in preparation

Single pion electroproduction (Q2 > 0)

Fit to the structure function data (~ 20000) from CLAS

Julia-Diaz, Kamano, Lee, Matsuyama, Sato, Suzuki, PRC80 025207 (2009)

p (e,e’ p0) p

W < 1.6 GeVQ2 < 1.5 (GeV/c)2

is determinedat each Q2.

N*N

g (q2 = -Q2)q

N-N* e.m. transitionform factor

Single pion electroproduction (Q2 > 0)Julia-Diaz, Kamano, Lee, Matsuyama, Sato, Suzuki, PRC80 025207 (2009)

p (e,e’ p0) p

p (e,e’ p+) n

Five-fold differential cross sections at Q2 = 0.4 (GeV/c)2