Hiroyuki Kamano

Energy Dependence of K̅N Interactions and Resonance Pole of Strange Dibaryons

We study the resonance energy of the strange dibaryons using two models with the energy-independent and energy-dependent potentials for the s-wave ¯ KN interaction, both of which are derived by certain reductions from the leading order term of the effective chiral Lagrangian. These potential models produce rather different off-shell behaviors of the two-body ¯ KN - πΣ amplitudes in I = 0 channel, i.e., the model with energy-independent (energy-dependent) potential predicts one (two) resonance pole in the Λ(1405) region, while they describe the available data equally well. We find that the energy-independent potential model predicts one resonance pole of the strange dibaryons, whereas the energy-dependent potential model predicts two resonance poles: one is the shallow quasi-bound state of the ¯ KNN , and the other is the resonance of the πY N with large width. An investigation of the binding energy of the strange dibaryons will make a significant contribution to clarify resonance structure of s-wave ¯ KN - πΣ around the Λ(1405) region. Subject Index: 232

Disentangling the Dynamical Origin of P11 Nucleon Resonances

We show that two almost degenerate poles near the piDelta threshold and the next higher mass pole in the P11 partial wave of piN scattering evolve from a single bare state through its coupling with piN, etaN, and pipiN reaction channels. This finding provides new information on understanding the dynamical origins of the Roper N{*}(1440) and N{*}(1710) resonances listed by Particle Data Group. Our results for the resonance poles in other piN partial waves are also presented.

Dynamical coupled-channels analysis of {sup 1}H(e,e{prime}{pi})N reactions.

We have performed a dynamical coupled-channels analysis of available p(e,e{sup }{pi})N data in the region of W{<=}1.6 GeV and Q{sup 2}{<=}1.45 (GeV/c){sup 2}. The channels included are {gamma}*N, {pi}N, {eta}N, and {pi}{pi}N that has {pi}{delta}, {rho}N, and {sigma}N components. With the hadronic parameters of the model determined in our previous investigations of {pi}N{yields}{pi}N, {pi}{pi}N reactions, we have found that the available data in the considered W{<=}1.6 GeV region can be fitted well by only adjusting the bare {gamma}*N{yields}N* helicity amplitudes for the lowest N* states in P{sub 33}, P{sub 11}, S{sub 11}, and D{sub 13} partial waves. The sensitivity of the resulting parameters to the amount of data included in the analysis is investigated. The importance of coupled-channels effect on the p(e,e{sup }{pi})N cross sections is demonstrated. The meson cloud effect, as required by the unitarity conditions, on the {gamma}*N{yields}N* form factors are also examined. Necessary future developments, both experimentally and theoretically, are discussed.

Structure of Λ(1405) and Threshold Behavior of πΣ Scattering

The scattering length and effective range of the πΣ channel are studied in order to characterize the strangeness S = −1 meson-baryon scattering and the Λ(1405) resonance. We examine various off-shell dependence of the amplitude in dynamical chiral models to evaluate the threshold quantities with the constraint at the ¯ KN threshold. We find that the πΣ threshold parameters are important to the structure of the Λ(1405) resonance and provide further constraints on the subthreshold extrapolation of the ¯ KN interaction. Subject Index: 232

Double and single pion photoproduction within a dynamical coupled-channels model

Within a dynamical coupled-channels model that has already been fixed by analyzing the data of the

Neutrino-induced forward meson-production reactions in nucleon resonance region

ensuremath{pi}Nensuremath{rightarrow}ensuremath{pi}N

On the extraction of P11 resonances from pi N data

and

Dynamical coupled-channels study of πN → ππN reactions

ensuremath{gamma}Nensuremath{rightarrow}ensuremath{pi}N

Extraction of nucleon resonances from global analysis of meson production reactions at EBAC

reactions, we present the predicted double pion photoproduction cross sections up to the second resonance region,

Dynamical coupled‐channels study of meson production reactions from EBAC@JLab

Wl1.7