336 citations · 5.5k across the 184 of their papers we have counts for
13 papers · 1 filter
The Nucleon and Roper Resonance in a Chiral Quark Diquark Model
Keitaro Nagata, Atsushi Hosaka
A description of the nucleon and Roper resonance in a quark-diquark approach is presented. We show that two states with the quantum number of the nucleon can appear in the ground s…
Phenomenological study of two-meson couplings of Theta+
Tetsuo Hyodo, Atsushi Hosaka
We evaluate two-meson couplings of Theta+, using experimental information of nucleon resonances decaying into pi pi N channels, in which the two pions are in scalar- and vector-typ…
Pentaquark Theta^+ production via gamma N ->K^*bar Theta^+(3/2^(+-))
Seung-Il Nam, Atsushi Hosaka, Hyun-Chul Kim
We study the photoproduction of the exotic pentaquark Theta^+ baryon with the vector kaon, assuming that the quantum numbers of the Theta^+ to be J^P=3/2^(+-) and J^P=1/2^+. Scalar…
Structure and reactions of pentaquark baryons
Atsushi Hosaka
We review the current status of the exotic pentaquark baryons. After a brief look at experiments of both positive and negative results, we discuss theoretical methods to study the…
Relation between the separable and one-boson-exchange potential for the covariant Bethe-Salpeter equation
Y. Manabe, A. Hosaka, H. Toki
We investigate the relation between the rank I separable potential for the covariant Bethe-Salpeter equation and the one-boson-exchange potential. After several trials of the param…
Two Nucleon-States in a Chiral Quark-Diquark Model
Keitaro Nagata, Atsushi Hosaka
We study the ground and first excited states of nucleons in a chiral quark-diquark model. We include two quark-diquark channels of the scalar-isoscalar and axial-vector-isovector t…
Non-interacting KN contribution in the QCD sum rule for the pentaquark Theta^+(1540)
Youngshin Kwon, Atsushi Hosaka, Su Houng Lee
We perform a QCD sum rule analysis for the pentaquark baryon Theta^+ with the non-interacting contribution treated carefully. The coupling of the Theta^+ current to the s…
Phenomenology of spin 3/2 baryons with pentaquarks
Tetsuo Hyodo, Atsushi Hosaka
We examine several assignments of spin and parity for the pentaquark Theta+ state (J^P=1/2^{+,-}, 3/2^{+,-}) in connection with known baryon resonances. Assuming that the Theta+ be…
Lambda(1520,3/2^-) photoproduction reaction via gamma N -> K Lambda(1520)
Seung-Il Nam, Atsushi Hosaka, Hyun-Chul Kim
We investigate Lambda(1520,3/2^-,D_03) photoproduction via the gamma N -> K Lambda^* reaction process. Using effective Lagrangians, we compute the total and differential cross sect…
Photoproduction of Lambda(1520,3/2^-)
Seung-Il Nam, Atsushi Hosaka, Hyun-Chul Kim
We investigate the photoproduction of Lambda(1520,3/2^-) via the gamma N -> K Lambda^* reaction using the Born approximation and the Rariata-Schwinger vector-spinor field for the s…
Dynamical baryon resonances from chiral unitarity
A. Ramos, C. Bennhold, A. Hosaka +6
We report on the latests developments in the field of baryonic resonances generated from the meson-baryon interaction in coupled channels using a chiral unitary approach. The colle…
Determination of the parity of the pentaquark baryons : Theta^+ and Xi_5
Seung-Il Nam, Atsushi Hosaka, Hyun-Chul Kim
We study determination of the parity of the pentaquark baryons in two different processes. First, we investigate the Theta^+ production via the vec{p} vec{p} -> Sigma^+ Theta^+ rea…
Two-meson cloud contribution to the baryon antidecuplet self-energy
T. Hyodo, A. Hosaka, F. J. Llanes-Estrada +3
We study the self-energy of the SU(3) antidecuplet coming from two-meson virtual clouds. Assuming that the exotic Theta+ belongs to an antidecuplet representation with N(1710) as n…