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Page 1: Exotics in meson-baryon dynamics with chiral symmetrytetsuo.hyodo/old/... · 1 00 200 300 "0# 200 150 100 50 0 1 00 200 30 0 "+$% 6 0 5 0 4 0 3 0 2 0 1 0 0! T [m b] 100 200 300 Pl

12006, Feb. 8th

Exotics in meson-baryon dynamics with chiral symmetry

Tetsuo Hyodoa

RCNP, Osakaa

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2

Introduction : QCD at low energy

At low energies... Color confinement Chiral symmetry breaking

Quantum chromodynamics (QCD): strong interaction of quarks and gluons

“exotics”Mesons, baryons (Hadrons)

: elementary excitations of QCD vacuum

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3

Introduction : Exotics

|B 〉 = | qqq 〉+| qqq(qq) 〉 + · · ·

|P 〉 = | qqqqq 〉+| qqqqq(qq) 〉 + · · ·

meson-baryonmolecule

two-meson cloud

Hadron structure meson-baryon dynamics

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4

Introduction : Hadronic description and symmetries

Guiding principle : symmetries of QCDChiral symmetry -> low energy theorem

mq → 0Flavor symmetry -> GMO formula

∆mq → 0

“exotics”Hadrons

Hadronic description • Observed in nature • Interaction can be measured in experiments

Symmetry

quark description

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5

IntroductionPart I : chiral unitary model

SU(3) breaking effectProduction of Λ(1405)Magnetic moments of N(1535)K* coupling to Λ(1520)

Part II : PentaquarksSpin parity determinationTwo-meson cloud8–10 representation mixingMeson induced Θ production

Summary

Contents

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6

Introduction : Λ(1405)

Λ(1405) : JP = 1/2−, I = 0

Mass : 1406.5 ± 4.0 MeVWidth : 50 ± 2 MeVDecay mode : 100%Λ(1405) → (πΣ)I=0

Coupled channel multi-scatteringR.H. Dalitz, T.C. Wong and G. Rajasekaran PR 153, 1617 (1967)

Quark model : p-wave, ~1600 MeV?N. Isgur, and G. Karl, PRD 18, 4187 (1978)

Part I : chiral unitary model

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7

Chiral unitary model

Unitarity of S-matrixChiral symmetry

Flavor SU(3) meson-baryon scatterings (s-wave)

Low energy behavior

Non-perturbativeresummation

JP = 1/2− resonances

Part I : chiral unitary model

• Theoretical foundation based on chiral symmetry• Analytically solvable —> information of the complex energy plane

Scattering amplitude

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8

Framework of the chiral unitary model : Interaction

LWT =1

4f2Tr(Biγµ[(Φ∂µΦ − ∂µΦΦ), B])

Chiral perturbation theory

Part I : chiral unitary model

chiral symmetry

V (WT )(KN → KN, I = 0) = − 34f2

(2√

s−MN−MN )√

EN + MN

2MN

√EN + MN

2MN

V (WT )(KN → πΣ, I = 0) =√

32

14f2

(2√

s−MN−MΣ)√

EN + MN

2MN

√EΣ + MΣ

2MΣ

Ex.)

Φ =

1√2π0 + 1√

6η π+ K+

π− − 1√2π0 + 1√

6η K0

K− K0 − 2√6η

B =

1√2Σ0 + 1√

6Λ Σ+ p

Σ− − 1√2Σ0 + 1√

6Λ n

Ξ− Ξ0 − 2√6Λ

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Framework of the chiral unitary model : Unitarization

Unitarization

Part I : chiral unitary model

T−1ij (

√s) = δij

(ai(s0) +

s − s0

∫ ∞

s+i

ds′ρi(s′)

(s′ − s)(s′ − s0)

)+ T −1

ij

T−1 = −G + (V (WT ))−1

T = V (WT ) + V (WT )GT

N/D method : general form of amplitude

V (WT )−Gi(√

s) = −i

∫d4q

(2π)42Mi

(P − q)2 − M2i + iε

1q2 − m2

i + iε

physical massesregularization of loop

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10T. Hyodo, Nam, Jido, Hosaka, PRC (2003), PTP (2004), Chap. 4.

200

150

100

50

0

!T [

mb

]

300200100

K-p

70

60

50

40

30

20

10

0300200100

"0#

200

150

100

50

0300200100

"+$%

60

50

40

30

20

10

0

!T [

mb

]

300200100Plab [MeV/c]

K0n

60

50

40

30

20

10

0300200100

Plab [MeV/c]

"0$0

80

60

40

20

0300200100

Plab [MeV/c]

"%$+

Total cross sections of K—p scatteringPart I : chiral unitary model

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Two poles?

There are two poles of the scattering amplitude around nominal Λ(1405) energy region.

1360

1380

1400

1420

1440

-20

-40

-60

-80

0.5

1.0

1.5

0.5

1.0

1.5

!(1405)

Re[z]Im[z]

|T|

• Chiral unitary model• Cloudy bag model

Part I : chiral unitary model

Tij(√

s) ∼ gigj√s − MR + iΓR/2

If there is a sufficient attraction, resonances can be dynamically generated.

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Λ(1405) in the chiral unitary model

800

600

400

200

01460144014201400138013601340

Ec.m.

[MeV]

200

150

100

50

0

_

KN -> !"!" #> !"

1390 - 66i ( )

1426 - 16i (KN)Re[z]

Im[z]

Part I : chiral unitary model

Real states? -> to be checked experimentally mass distribution

Shape of πΣ spectrum depends on initial state

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Production reaction for the Λ(1405)

In order to clarify the two-pole structure,we study two reactions.

Part I : chiral unitary model

π−p → K0Λ(1405) → K0πΣ

γp → K∗Λ(1405) → K0π+πΣ

dMI= C|tπΣ→πΣ|2pCM

dMI= |

∑i

Citi→πΣ|2pCM

• higher energy pole?T. Hyodo, Hosaka, Vacas, Oset, PLB (2004), Section 5.3

• Experimental result -> lower energy poleT. Hyodo, Hosaka, Oset, Ramos, Vacas, PRC (2003), Section 5.2

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Photoproduction of K* and Λ(1405)Part I : chiral unitary model

Σ(1385) is included <- background estimation

Only K p channel appears at the initial stage—> higher energy pole

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Advantage of this reaction

LK∗Kγ = gK∗Kγεµναβ∂µAν(∂αK∗−β K+ + ∂αK∗0

β K0) + h.c.

γ

LV PP = − igV PP√2

Tr(V µ[∂µP, P ])

π

With polarized photon beam, the exchangedparticle can be identified.

Part I : chiral unitary model

Clear mechanism

photon polarization —> K* polarization—> Kπ decay plane

For 0+ meson emission, is absent.εµναβ

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Isospin decomposition of final states

• Mixture of I=0 and I=1

• Pure I=0 amplitude <— Λ(1405)

Since initial state is KN, no I=2 component.

• Pure I=1 amplitude <— Σ(1385)

Part I : chiral unitary model

σ(π0Σ0) ∝ 13|T (0)|2

σ(π0Λ) ∝ |T (1)|2

σ(π±Σ∓) ∝ 13|T (0)|2 +

12|T (1)|2 ± 2√

6Re(T (0)T (1)∗)

} dσ

dMI

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Total cross sections0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

[b]

300028002600240022002000

s [MeV]

(I=0)

+ -

- +

(I=1)

K*K

Part I : chiral unitary model

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18

Invariant mass distributions

Plab = 2.5 GeV/csqrt s ~ 2.35 GeV

4

3

2

1

0

d/d

MI[

nb/M

eV

]

15001450140013501300

MI [MeV]

0 0

(I=0)

+ -

- +

(I=1)

Part I : chiral unitary model

Thomas et al., (1973)π−p → K0πΣ

• dominance of higher pole -> different shape

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Isospin decomposition of charged πΣ states

• Difference between charged states -> interference term of I=0 and 1

dσ(π±Σ∓)dMI

∝ 13|T (0)|2 +

12|T (1)|2 ± 2√

6Re(T (0)T (1)∗)

Charged πΣ states

Part I : chiral unitary model

Taking average of two states, this term vanishes.

dσ(π0Σ0)dMI

∝ 13|T (0)|2

Difference from neutral channel : I=1, Σ(1385)

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Invariant mass distributions 2

Plab = 2.5 GeV/csqrt s ~ 2.35 GeV

Part I : chiral unitary model

Σ(1385) contribution is small

4

3

2

1

0

d/d

MI[

nb

/MeV

]

15001450140013501300

MI [MeV]

0 0

(I=0)

( + -

+ - +

) / 2Thomas et al., (1973)π−p → K0πΣ

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21

In the chiral unitary model, Λ(1405) is generated as a quasi-bound state in coupled channel meson-baryon scattering.There are two poles of the scattering amplitude around nominal Λ(1405).

Conclusion for part I

Pole 1 (1426–16i) : strongly couples to KN statePole 2 (1390–66i) : strongly couples to π state

We study the structure of Λ(1405) using the chiral unitary model.

Part I : chiral unitary model

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22

We propose the reaction, which provides a different shape of spectrum from the nominal one. Observation of this feature give a support of the two-pole structure.We estimate the effect of Σ(1385) in I=1 channel, which is found to be small for the πΣ spectrum.

Conclusion for part I

γp → K∗Λ(1405)

Part I : chiral unitary model

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23

LEPS, T. Nakano, et al., Phys. Rev. Lett. 91, 012002 (2003)

|Θ 〉 = |uudds 〉S = +1, manifestly exotic

Properties of the ΘPart II : pentaquarks

light mass 1540 MeVMΘ ∼ 4mud + ms ∼ 1700 MeV

narrow width < 15 MeV (1 MeV)ΓB∗ ∼ 100 MeV

Is it possible to describe the Θ by hadrons?

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24

Hadronic description : Two-body molecule?

In order to have the narrow width, it must be in d-wave or higher.

Part II : pentaquarks

VWT = 0 for I = 0, S = +1

—> no interaction for s-wave—> Chiral unitary model ×

States in higher partial waves are expected to be heavy, and unnatural for the ground state.

It is difficult to reproduce the Θ properties.

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25

Three-body molecule

MK + Mπ + MN ∼ 1570 MeV

An attraction was found, but not strong enough to bind the system.

Part II : pentaquarks

Only 30 MeV attraction can form the Θ.Decay into KN requires the absorption of π—> p-wave excitation —> suppressed

P. Bicudo, et al., Phys. Rev. C69, 011503 (2004)T. Kishimoto, et al., hep-ex/0312003F. J. Llanes-Estrada, et al., Phys. Rev. C69, 055203 (2004)

Narrow and light state?

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Two-meson cloud effectPart II : pentaquarks

How large the πKN effects in Θ?Hosaka, Hyodo, Estrada, Oset, Peláez, Vacas, PRC (2005), Chap. 9.

Γ : small

coupling?

• Evaluate self-energy around “core”• Coupling constant <— antidecuplet + SU(3)

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Two-meson coupling

10–20 %Θ+ → KNN(1710) → πN

N(1710) → ππNΘ+ → KπN

40–90 %Forbidden

Very narrow

Effective interactions which account for the decayN(1710) → ππN

Part II : pentaquarks

N(1710) is assumed to be a partner of Θ.

Large??

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SU(3) structure of effective Lagrangian

8M 8M

8B10P

1 ∈ 10 ⊗ 10

Part II : pentaquarks

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Construction of interaction Lagrangians

Ex.) Construction of 8s LagrangianDi

j [8sMM ] = φi

aφaj + φi

aφaj − 2

3δi

jφabφb

a

= 2φiaφa

j − 23δi

jφabφb

a

T ijk[10BMM(8s)] = 2φlaφa

iBmjεlmk + (i, j, k symmetrized)

L8s =g8s

2fPijkεlmkφl

aφaiBm

j + h.c.

Part II : pentaquarks

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Interaction Lagrangians

N(1710) → ππ(p-wave, I = 1)NN(1710) → ππ(s-wave, I = 0)NExperimental information

L8s =g8s

2fPijkεlmkφl

aφaiBm

j + h.c.

L8a = 0

L10 = 0 <- symmetry under exchange of mesonsL27 =

g27

2f

[4Pijkεlbkφl

iφajBb

a − 45Pijkεlbkφl

aφajBb

i

]+ h.c.

8s

8a

Terms without derivative

L8a = ig8a

4f2Pijkεlmkγµ(∂µφl

aφai − φl

a∂µφai)Bm

j + h.c.

With one derivative

Part II : pentaquarks

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Diagrams for self-energy

g8s = 1.88 , g8a = 0.315N(1710) decay

8s 8s

Part II : pentaquarks

Imaginary partSU(3) breaking

: decay width: masses of particles

−∫

d4k

(2π)4

∫d4q

(2π)4|t(j)|2 1

k2 − m21 + iε

1q2 − m2

2 + iε

M

E

1p0 − k0 − q0 − E + iε

vertex=

∫d3k

(2π)3

∫d3q

(2π)3|t(j)|2 1

2ω1

12ω2

M

E

1p0 − ω1 − ω2 − E + iε

Evaluate in the rest frameN.R. approx. for baryon

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Diagrams for self-energy

Real part : Principle value integral for mass shift.

Part II : pentaquarks

p0 = energy of antidecuplet

Σ(j)P (p0) =

∑B,m1,m2

(F (j)C(j)

P,B,m1,m2

)I(j)(p0;B,m1,m2)

(F (j)C(j)

P,B,m1,m2

)

Σ8aΘ (p0) =

(F 8a

)2 [18I8a(p0;N,K,π) + 18I8a(p0;N,K, η)]

divergent <— cutoff

I(j)(p0;B,m1,m2) =∫

d3k

(2π)3

∫d3q

(2π)3|t(j)|2 1

2ω1

12ω2

M

E

1p0 − ω1 − ω2 − E + iε

qmax = kmax = 700–800 MeV

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Coupled channel summationPart II : pentaquarks

Σ

ΛΛπηΛππΣΣππΣπηΣηηΞΞ

Θ

ΛΛΣΣ

Ξ ΣΣΞΞπηΞππ

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Results of self-energy : Real part (mass shift)

-140

-120

-100

-80

-60

-40

-20

0

Re

[M

eV]

p0 = 1700 MeV

cutoff = 700 MeV

N

8s

8s + 8a

-140

-120

-100

-80

-60

-40

-20

0

Re

[M

eV]

p0 = 1700 MeV

cutoff = 800 MeV

N

8s

8s + 8a

Mass splitting is nearly equal spacing.All mass shifts are attractive (~100 MeV for Θ).

Mass difference between Ξ and Θ -> 60 MeV : ~20% of 320 = 1860–1540 MeV

Part II : pentaquarks

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Discussion

All mass shifts are attractive.

Part II : pentaquarks

-> Existence of attraction is consistent with previous attempts.

Mass splitting is nearly equal spacing.-> Deviation from GMO formula due to two-meson cloud is not very large.

Two-meson cloud also provides substantial effect for N and Σ.

-> It originates in the large coupling of the N(1710) to the three-body channels.

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Conclusion for part II

We study the two-meson virtual cloud effect to the self-energy of baryon antidecuplet.

Two types of interaction Lagrangians (8s, 8a) are derived in order to estimate the two-meson cloud.

L8s =g8s

2fPijkεlmkφl

aφaiBm

j + h.c.

L8a = ig8a

4f2Pijkεlmkγµ(∂µφl

aφai − φl

a∂µφai)Bm

j + h.c.

Part II : pentaquarks

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37

Two-meson cloud effects are always attractive, of the order of 100 MeV for the Θ. It plays an important role to understand the nature of the Θ.Mass difference shows nearly equal spacing, and two-meson cloud provides 20% of the empirical one.

Part II : pentaquarksConclusion for part II

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38

SummaryWe study the “exotics” in hadron dynamics based on chiral and flavor symmetries.

Chiral unitary model provides a good description of the Λ(1405) as meson-baryon molecule.The two-pole structure of the Λ(1405) can be tested experimentally.The two-meson cloud provides ~100 MeV attraction for the Θ and about 20% of the mass splitting for 10.

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39

Summary

There are appreciable meson cloud (higher Fock components) effects in baryons and pentaquarks due to meson-baryon dynamics, which complement the valence quarks.It is important to test the hadron properties experimentally.Symmetries provide a way to study hadrons systematically.

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40

Appendix

ChU

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41

Appendix : ChPT Lagrangian

B =

1√2Σ0 + 1√

6Λ Σ+ p

Σ− − 1√2Σ0 + 1√

6Λ n

Ξ− Ξ0 − 2√6Λ

L(1) = Tr(B(i/D − M0)B − D(Bγµγ5{Aµ, B}) − F (Bγµγ5[Aµ, B])

)DµB = ∂µB + i[Vµ, B]

D + F = gA

=i

4f2(Φ∂µΦ − ∂µΦΦ) + · · ·

= − 1f

∂µΦ + · · ·

ξ(Φ) = exp{iΦ/√

2f}

Φ =

1√2π0 + 1√

6η π+ K+

π− − 1√2π0 + 1√

6η K0

K− K0 − 2√6η.

Aµ = − i

2(ξ†∂µξ − ξ∂µξ†)

Vµ = − i

2(ξ†∂µξ + ξ∂µξ†)

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42

Two-pole structure

Are they real states? —> need to check experimentally

Part I : chiral unitary model

π−p → K0Λ(1405) → K0πΣ

• Experimental results available so far:Thomas et al., (1973)

Hemingway et al., (1984)

Σ∗(1660)+ → π+Λ(1405) → π+πΣ• PDG : analysis based on the Hemingway data assuming one state

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43

Trajectories of the poles with SU(3) breaking (S = -1)

D. Jido, et al., Nucl. Phys. A 723, 205 (2003)

8×8 ~ 1,8,8,10,10,27attractive (WT term)250

200

150

100

50

0

Im z

R [

Me

V]

17001600150014001300

Re zR [MeV]

1390

(I=0) 1426

(I=0) 1680

(I=0)

1580

(I=1)

disappear

(I=1)

Singlet Octet

=0.5

x=1.0

x=0.5 x=1.0

=1.0

x=0.5

x=0.5

x=1.0

x=0.5

x=0.6

x

x

Part I : chiral unitary model

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44

Application to the reaction

V.K. Magas, et al., hep-ph/0503043

1.3 1.35 1.4 1.45 1.5 1.550

0.5

1

1.5

2

2.5x 10

!12

MI, GeV

d/d

MI,

arb

. u

nits K

! p !!>

0

0

0

! p !!> K

0

M =1395 MeV

M =1420 MeV

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45

Improvement of mass distributionsPart I : chiral unitary model

Inv

ari

an

t m

ass

dis

trib

uti

on

[arb

. u

nit

s]

150014801460144014201400138013601340

MI [MeV]

Total Chiral term Resonance term

Invari

ant

mass

dis

trib

uti

on [

arb

. unit

s]

150014801460144014201400138013601340

MI [MeV]

Total Chiral term Resonance term

Plab = 1.66 GeV/c Plab = 1.55 GeV/c

• Consistency between amplitude and phase space• Σ(1385) contribution• Approximation for loop

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46

Controversial?

B. Borasoy., et al., hep-ph/0505239

Inclusion of O(p2) terms: one pole moves far away from the real axis

Similar study butwith O(p2) terms

DEAR experiment: kaonic hydrogen

1380 1400 1420 1440 1460

-160

-140

-120

-100

-80

-60

-40

-20

0

O(p2)

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47

I=1, s-wave amplitude

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

d/d

MI[

nb/M

eV]

15001450140013501300

MI [MeV]

+ - - +

(I=1, s) (I=1, s and p)

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48

Appendix

PENTA

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49

Test for inter-quark correlation

multi-quark states, quark matter, ...

Part II : pentaquarksPentaquarks : Importance

QCD does not forbid it.

pentaquark (qqqqq) ∋ qq(color 6), ...

meson (qq) ∋ only qqbaryon (qqq) ∋ only qq(color 3)

Heavy pentaquark <- large Nc and heavy MQ

Exotics <- Duality in scattering theoryRather, existence was implied;

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50

|Θ 〉 = |uudds 〉light mass 1540 MeV

narrow width < 15 MeV (1 MeV)

MΘ ∼ 4mud + ms ∼ 1700 MeV

ΓB∗ ∼ 100 MeVΓΛ(1520) ∼ 20 MeV <— spin 3/2 (d-wave)

MK + MN ∼ 1430 MeV <— qq correlation

Properties of the ΘPart II : pentaquarks

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51

Motivations

γd -> Λ*Θ+ at SPring-8

Anomalies in production experiments

Possibility of Θ+~KπN bound stateP. Bicudo, et al., Phys. Rev. C69, 011503 (2004)T. Kishimoto, et al., hep-ex/0312003F. J. Llanes-Estrada, et al., Phys. Rev. C69, 055203 (2004)

p Θ+

π-p -> K-Θ+ at KEK

π−(K+) K−(π+)

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52

Criteria to construct the Lagrangian

Interaction is flavor SU(3) symmetric

T.D. Cohen, Phys. Rev. D70, 074023 (2004)S. Pakvasa and M. Suzuki, Phys. Rev. D70, 036002 (2004)T. H. and A. Hosaka, Phys. Rev. D71, 054017 (2005)

Assumptions for Θ+N(1710) is the S=0 partner of antidecuplet-> JP = 1/2+

No mixing with 8, 27,... <- decay width

Small number of derivativesChiral symmetric? -> later

low energy : OK

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53

Two-meson cloud effect

Let us assume Θ belongs to the antidecuplet, and evaluate the self-enrgy coming from the two-meson cloud.

Part II : pentaquarks

How much the three-body components in Θ?

MΘ = M0 + ReΣΘ

MN = M0 + ∆ + ReΣN

MΣ = M0 + 2∆ + ReΣΣ

MΞ3/2 = M0 + 3∆ + ReΣΞ3/2

GMO rule

Two-meson cloud

A. Hosaka, T. H., et al., Phys. Rev. C71, 045205 (2005), Section 9.

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54

π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Interaction Lagrangians 1

P 333 =√

6Θ+10

P 133 =√

2 N010 P 233 = −√

2 N+10

P 113 =√

2Σ−10 P 123 = −Σ0

10 P 223 = −√2 Σ+

10

P 111 =√

6Ξ−−10 P 112 = −√

2 Ξ−10 P 122 =

√2Ξ0

10 P 222 = −√6Ξ+

10

Antidecuplet field

Meson and baryon fields

B =

1√2Σ0 + 1√

6Λ Σ+ p

Σ− − 1√2Σ0 + 1√

6Λ n

Ξ− Ξ0 − 2√6Λ

Φ =

1√2π0 + 1√

6η π+ K+

π− − 1√2π0 + 1√

6η K0

K− K0 − 2√6η

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Other possible Lagrangians : detail

L8s =g8s

2fPijkεlmkφl

aφaiBm

j + h.c.

Two-meson 27 interactionL27 =

g27

2f

[4Pijkεlbkφl

iφajBb

a − 45Pijkεlbkφl

aφajBb

i]

+ h.c.

Lχ =gχ

2fPijkεlmk(Aµ)l

a(Aµ)aiBm

j + h.c.

Aµ =i

2(ξ†∂µξ − ξ∂µξ†

)= − ∂µφ√

2f+ O(p3)

(Aµ)la(Aµ)a

i → 12f2

∂µφla∂µφa

i

Chiral symmetric interaction

ξ = eiφ/√

2f

LM =gM

2fPijkεlmkSl

iBmj

S = ξMξ + ξ†Mξ† = O(φ0) − 12f2

(2φMφ + φφM + Mφφ) + O(φ4)

SU(3) breaking interaction M = diag(m, m,ms)

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Chiral symmetric Lagrangian

L8s =g8s

2fPijkεlmkφl

aφaiBm

j + h.c.

Lχ(2) =gχ

2fPijkεlmk 1

2f2∂µφl

a∂µφaiBm

j + h.c.

SU(3) structure : Identical !Only loop integral is changed<- adjusting the cutoff, we would have the same results

gχ = 0.218N(1710) decay ->

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Results of chiral Lagrangian

Re{Σ} 8s χ(2)Θ -100 -99N -87 -83Σ -79 -70Ξ -63 -57cutoff 800 525

Decay 8s χ(2)N(1710) → Nππ 25 25N(1710) → Nηπ 0.58 0.32Σ(1770) → NKπ 4.7 4.5Σ(1770) → Σππ 10 3.6Ξ(1860) → ΣKπ 0.57 0.40

Almost the same resultsDifference comes from the SU(3) breaking of momenta at the vertex

[MeV]

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

27 and mass Lagrangians

Fitting couplings to the N(1710) decay -> large binding energy of 1 GeV : unrealisticTreat them as a small perturbation to the 8s.

L27 =g27

2f

[4Pijkεlbkφl

iφajBb

a − 45Pijkεlbkφl

aφajBb

i]

+ h.c.

Lint = aL8s + b27,ML27,M

Deviation from a = 1 : weight of new terms

g27 = gM = g8s = 1.88 , b27 = −54(1 − a) , bM =

f2

m2π

(1 − a)

LM =gM

2fPijkεlmk(− 1

2f2)(2φMφ + φφM + Mφφ)l

iBmj + h.c.

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π−p

K+

n

K+

π+

p

K+

n

K+

π+

∆+

ρ0

p

K+

n

π+

K+

Results of 27 and mass Lagrangians

Contributions of these terms are considered as a theoretical uncertainty in the analysis.

-250

-200

-150

-100

-50

0

Re

[M

eV]

p0 = 1700 MeV

cutoff = 800 MeV

N-120

-100

-80

-60

-40

-20

0

Re

[M

eV]

p0 = 1700 MeV

cutoff = 800 MeV

N

27 M0.90 < a < 1.06 0.76 < a < 1.06