Related papers: A pentaquark picture of Lambda(1405)
We test a pentaquark model of the negative parity hyperon Lambda(1405). We use the model where valence four quarks and one antiquark move in a potential relativisticaly and interact with themselves and each other through gluon and NG boson.…
We study a pentaquark model of the negative parity hyperon Lambda(1405). We choose a specific quark configuration for trial, and use the perturbative chiral quark model extended to four quarks and one anti-quark system. We calculate a…
The splittings between positive parity pentaquarks containing a single heavy (c,b) antiquark and four light (u,d) quarks are investigated in models having spin-dependent interactions generated by either effective Goldstone boson exchange or…
We review briefly recent studies of the Lambda(1405) spectrum in Lattice QCD. Ordinary three-quark pictures of the Lambda(1405) in quenched Lattice QCD fail to reproduce the mass of the experimental value, which seems to support the…
The properties of the Lambda(1405) resonance are key ingredients for determining the antikaon-nucleon interaction in strangeness nuclear physics, and the novel internal structure of the Lambda(1405) is of great interest in hadron physics,…
Assuming the two diquark structure for the pentaquark state as advocated in the Jaffe-Wilczek model, we study the strong decays of light and heavy parity-even pentaquark states using the light-front quark model in conjunction with the…
Among the light baryons, the $J^\pi = \frac{1}{2}^-$ $\Lambda(1405)$ hyperon is an important special case as it sits just below the $N\bar{K}$ threshold and decays almost exclusively to $\Sigma\pi$. Some long-standing hypotheses for…
We have investigated uudd\sbar pentaquarks by employing quark models with the meson exchange and the effective gluon exchange as qq and q\qbar interactions. The system for five quarks is dynamically solved; two quarks are allowed to have a…
$\Lambda(1405)$ is one of the interesting particles with its unclear structure and distinct properties. It has a light mass compared to its non-strange counterpart, despite the strange quark it carries. This situation puts the investigation…
We have investigated negative-parity uudd\bar{s} pentaquarks by employing a quark model with the meson exchange and the effective gluon exchange as qq and q\bar{q} interactions. The system for the five quarks is dynamically solved; the…
The strong and electromagnetic properties of the Lambda(1405) hyperon are studied in the framework of the bound state soliton model. We explicitly evaluate the strong coupling constant g(Lambda^*-N-K), the Lambda^* magnetic moment, mean…
We investigate the negative-parity baryon spectra in quenched lattice QCD. We employ the anisotropic lattice with standard Wilson gauge and O(a) improved Wilson quark actions at three values of lattice spacings with renormalized anisotropy…
We explore how well one can probe the s quark chirality of the fundamental weak interaction of nonleptonic B decay using the spin-analyzing property of the Lambda hyperon. We present the prediction of the Standard Model as quantitatively as…
The strange-anticharmed Pentaquark is a $uud\bar{c}s$ or $udd\bar{c}s$ five-quark baryon that is expected to be either a narrow resonance, or possibly even stable against strong and electromagnetic decay. We describe this hyperon here, its…
We discuss certain general features of the pentaquark picture for the theta, its 10bar_F partner, Xi_{3/2}, and possible heavy quark analogues. Models employing spin-dependent interactions based on either effective Goldstone boson exchange…
Weak radiative hyperon decays are considered in the framework of a quark model. The phenomenological model includes 1-quark transitions with the effective $sd\gamma$-vertex and 2-quark ones with the W-exchange $s+u\to u+d+\gamma$ and turns…
We discuss the properties of the pentaquark in a collective stringlike model with a nonplanar configuration of the four quarks and the antiquark. In an application to the mass spectrum of exotic Theta baryons, we find that the ground state…
The Lambda(1405) baryon resonance plays an outstanding role in various aspects in hadron and nuclear physics. It has been considered that the Lambda(1405) resonance is generated by the attractive interaction of the antikaon and the nucleon,…
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 structure and reactions for the pentaquarks. First we…
$QQ^\prime qq\bar q$ pentaquarks are studied in a potential model, under the hypothesis that they are composite objects of two diquarks and one antiquark. The interaction between two colored objects includes two contributions, one based on…