Dynamical coupled-channels - PowerPoint Presentation

Slide1

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, 2012Slide2

OutlineResults of 5-year project on nucleon resonance extraction at EBAC@JLab

Theory projects for strangeness production reactions on the nucleons and nuclei Slide3

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

k

eV

to

~10 MeV

Each resonance peak is

clearly separated

.Slide4

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

photoproduction

s

Opens a great opportunity to make

quantitative

study of

the N* states !! Slide5

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

Q

C

D

Lattice QCD

Hadron 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) 193Slide6

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

D

p

D

p

p

p

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* states

N*

bare

D

p

N

p

p

D

D

N

p

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:Slide7

DCC analysis @ EBAC (2006-2009)

p N  p N : Analyzed to construct a hadronic part of the model

up

to W = 2

GeV

Julia-Diaz, Lee, Matsuyama, Sato, PRC76 065201 (2007)

p

N 

h

N :

Analyzed to construct a hadronic part of the model

up to W = 2

GeV Durand, Julia-Diaz, Lee, Saghai, Sato, PRC78 025204 (2008)

p

N 

p

p

N : First fully dynamical coupled-channels calculation

up to W = 2 GeV

Kamano, 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 Q

2

= 1.5 GeV

2

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

Stability and model dependence of P11 resonance poles extracted from pi N  pi N data

Kamano

, Nakamura, Lee, Sato, PRC81 065207 (2010) Extraction of gN  N* electromagnetic transition form factors Suzuki, Sato, Lee,

PRC79 025205 (2009); PRC82 045206 (2010)

Hadronic part

Electromagnetic part

Extraction of N* parameters

p

N

, hN

,

pp

N

(

pD

,

r

N

,

s

N

)

coupled-channels

calculations

were performed.Slide8

Dynamical coupled-channels effect on N* spectrum

Pole positions and dynamical origin of P11 resonancesSuzuki, Julia-Diaz, Kamano, Lee, Matsuyama, Sato, PRL104 065203 (2010)

pole A:

pD

unphys. sheet

pole B:

pD

phys. sheetSlide9

Dynamical Coupled-Channels analysis (current status)



p





N

g

p

 

N 

-p  h

n

gp  hp pp 

K

L

, K

S

g

p



K

L

, KS

2006 ~ 2009

5 channels

(

p

N,

h

N,

pD

,rN,s

N)< 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 , N



N , hN ,

KL, K

S

reactions !!

Kamano, Nakamura, Lee, Sato, in preparationSlide10

Partial wave amplitudes of pi N scattering

Current model

(

fully combined

analysis,

PRELIMINALY

)

Previous model

(fitted to

p

N



p

N data

only

)

[PRC76 065201 (2007)]

Real part

Imaginary part

Kamano, Nakamura, Lee, Sato

in preparationSlide11

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

MeVSlide12

Spectrum of N* resonances

Real parts of N* pole values L2I 2JPRELIMINARY!!

PDG

Ours

N* with 3*,

4*

18

16

N* with 1*, 2*

5

PDG 4*

PDG 3*

Ours

Kamano, Nakamura, Lee, Sato in preparationSlide13

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

Width of N* resonancesKamano, Nakamura, Lee, Sato in preparationSlide14

Theory Projects for Strangeness Production

Reactions on the Nucleons and NucleiParticipants: 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

1

st

discussion meeting:

Dec. 4-10 2011 @

Kyungpook

U., Korea

GOALSlide15

1. Baryon spectroscopy of the strangeness sectorExtends DCC approach to analyze

Y* production reactions andestablish L*, S*, and also X* spectroscopy.

K

L

*,

S

*

N

K,

p

, K

N,

S

,

X

K

L

*,

S

*

N

K

X*

M

B

(CLAS)

L

*,

S

*

N

K

X*

M

B

N

*,

D

*

K

g

In photon-induced

experiment, one has to

analyze

four

-body

production reactions.Slide16

2. Determination of YN and YY interactions via

pion- and kaon-induced deuteron reactions

Y

p

,

K

N

K

_

d

Y

p

Y

K

_

d

K

Y

K

N

d

p

Elemental meson-production

amplitudes are provided

from

our dynamical coupled-channels

approach.Slide17

A

Y = L, S, X

p

, K

K

_

A

A

LL

K

_

A

L

L

K

3

. Applications to production reactions of

hypernuclei

Determined

YN, YY

interactions

Many-Body Theory

Properties of A

Y,YYSlide18

back upSlide19

N, N*

Meson cloud effect in gamma N  N* form factorsGM(Q2) for

g

N



D

(1232) transition

Note:

Most of the available static

hadron models give

G

M(Q

2) close to “Bare” form factor.

Full

BareSlide20

“Static” form factor from

DSE-model calculation.

(C. Roberts et al)

A clue how to connect with static hadron models

“Bare” form factor

determined from

our

DCC analysis.

g

p

 Roper

e.m

. transitionSlide21

g N

 D(1232) form factors compared with Lattice QCD dataoursSlide22

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 !!Slide23

Partial wave amplitudes of pi N scattering

Current model

(

fully combined

analysis,

PRELIMINALY

)

Previous model

(fitted to

p

N



p

N data

only

)

[PRC76 065201 (2007)]

Real part

Imaginary partSlide24

gamma p  K+ Lambda, K+ Sigma0

Preliminary!!

1781 MeV

2041 MeV

P

olarization 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 preparationSlide25

Pion-nucleon elastic scattering

Current model (fully combined analysis, preliminary)

Previous model (fitted to

p

N



p

N data

only

)

[PRC76 065201 (2007)]

Target polarization

1234 MeV

1449 MeV

1678 MeV

1900 MeV

Angular distribution Slide26

Single pion photoproduction

Current model (fully combined analysis, preliminary

)

Previous model (fitted to

g

N



p

N 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 preparationSlide27

Data handled with

the help of R. Arndtpi N  pi pi N reaction

Parameters used in the calculation are from

p

N



p

N analysis.

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

Full result

Phase space

Full result

W (GeV)

s

(mb)

(# of

p

N



pp

N

data) /

(# of

p

N



p

N

data)

~ 1200 / 24000

Above

W = 1.5

GeV

,

All

p

N



pp

N

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

!!Slide28

Double pion photoproduction

Kamano, Julia-Diaz, Lee, Matsuyama, Sato, PRC80 065203 (2009)

Parameters used in the calculation are from

p

N



p

N &

g

N 

p

N analyses.

Good description near threshold

Reasonable shape of invariant

mass distributions

Above 1.5 GeV, the total cross

sections of

p



0



0

and

p

+



-

overestimate the data. Slide29

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 asymmetrySlide30

Single pion photoproduction

Current model (fully combined analysis, preliminary

)

Previous model (fitted to

g

N



p

N 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 MeVSlide31

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 preparationSlide32

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’

p

0

) p

W

<

1.6

GeV

Q

2

<

1.5

(GeV/c)

2

is determined

at each Q

2

.

N*

N

g

(q

2

= -Q

2

)

q

N-N*

e.m

. transition

form factorSlide33

Single pion electroproduction (Q2 > 0)

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

p (e,

e’

p

0

) p

p (e,

e’

p

+

) n

Five-fold differential cross sections at Q

2

= 0.4 (GeV/c)

2