L(1405) production in the p-p -> K0pS reaction

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L(1405) production in the p-p -gt K0pS reaction

• Tetsuo Hyodoa

A. Hosakaa, E. Osetb, A. Ramosc and M. J. Vicente
Vacasb
a RCNP, Osaka b IFIC, Valencia c Barcelona
Univ.
2003, July 31st
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Contents
MB scattering

1. Motivation
2. Chiral unitary model
3. L(1405) in the chiral unitary model
4. Model for p-p -gt K0pS
5. Results
6. Conclusions
7. Experiments a

T. Hyodo, et al., nucl-th/0307005
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Motivations Two poles?
There are two poles of the scattering
amplitude around nominal L(1405) energy region.
L(1405) JP1/2-, I0

• Cloudy bag model
• (1990)
• Fink et al. PRC41, 2720
• Chiral unitary model
• (2001)
• Oller et al. PLB500, 263
• Oset et al. PLB527, 99
• Jido et al. PRC66, 025203
• Hyodo et al. PRC68, 018201

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Chiral unitary model
Flavor SU(3) meson-baryon scatterings (s-wave)
Unitarity of S-matrix
Chiral symmetry
Low energy behavior
Non-perturbative resummation
Dynamical generation
Resonances
L(1405), L(1670), N(1535), S(1620), X(1620)
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Framework of the chiral unitary model
Chiral perturbation theory
Unitarization
Generated resonances are expressed as poles of
the scattering amplitude.
Resonances
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L(1405) in the chiral unitary model
Two poles 1390 66i (pS), 1426 16i (KN)
pS mass distribution
D. Jido, et al., nucl-th/0303062
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Mechanism of p-p -gt K0pS
? at rest
p-p c.m. frame ? pS c.m. frame
Channel MB KN, pS, pL, hL, hS, KX
Chiral unitary model
pS invariant mass distribution -gt L(1405)
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Chiral amplitude for p-p -gt K0pS
Construct the initial stage interaction from ChPT.
Meson 4-point vertex
Yukawa vertex
Generalized Yukawa vertex
At low energies, these two diagrams are relevant.
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Chiral amplitude for p-p -gt K0pS results
Do not agree!!
Experiment D. W. Tomas, et al., NPB56, 15(1973)
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N(1710) contribution for p-p -gt K0pS
Initial c.m. energy of p-p system ? 1.9GeV -gt
resonance excitation in the initial stage P11
resonance s-wave coupling to MMB
N(1710) -gt p N (10-20 ) -gt p p
N (40-90 ) -gt h p N (no)
Extrapolation of ppN decay
pN decay
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Final results for p-p -gt K0pS
Good retult!!
N(1710)
Chiral terms
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Conclusions
We calculate the p-p -gt K0pS reaction using the
chiral unitary model.

• There are two mechanisms in the initial
• stage interaction.
• They filter each one of the resonances.
• Combination of the two mechanisms
• gives a good description of data.

higher pole (142616i) lower pole (139066i)
chiral term N(1710) contribution
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Experiments pS mass distribution
gp -gt K-pS
J.C. Nacher, et al., PLB445, 55(1999)
Spring-8
K-p -gt gpS
J.C. Nacher, et al., PLB461, 299(1999)
J-PARC?
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a Q production in Kp -gt pKn
Q 5-quark (4 quark 1 anti-quark)
LEPS, T. Nakano et al., Phys. Rev. Lett. 91
(2003) 012002
Parity 1/2 ? 1/2- ?
Kp -gt pKn
Polarization test
T. Hyodo, A. Hosaka, and E. Oset, nucl-th/0307105