Related papers: Phenomenological study for the Theta+ and two-meso…

We report on a study of the pentaquark Theta^+(1540), using a variety of different interpolating fields. We use Chirally Improved fermions in combination with Jacobi smeared quark sources to improve the signal and get reliable results even…

We study the decay of Theta+ in a non-relativistic quark model. The wave function of Theta+ is constructed for the two cases JP = 1/2+- as products of color, spin, flavor and orbital parts respecting total antisymmetrization among the four…

A strangeness +1 exotic baryon Theta^+ has recently been seen in a number of experiments. We demonstrate that in large N_c QCD the existence of such a state implies the existence of S = +1 partner states with various spins and isospins but…

We investigate the photoproduction of the $\Theta^+(1540)$ on a nucleon ($\gamma n \to K^- \Theta^+$, $\gamma p \to \bar{K}^0 \Theta^+$) and the pion-induced $\Theta^+$ production reaction on the proton ($\pi^- p \to K^- \Theta^+$). The…

Using the exisiting experimental data for hyperon semileptonic decays and the flavor-singlet axial-vector charge $g_{A}^{(0)}$ from polarized deep inelastic scattering of the proton, we derive the decay width of the $\Theta^{+}$ pentaquark…

We investigate the meson-baryon interaction in coupled channels with the quantum numbers of the pentaquarks $P_{bss}$ and $P_{bsss}$. The interaction is derived from an extension of the local hidden gauge approach to the heavy quark sector,…

Production cross sections of the pentaquark Theta+ baryon in the meson-induced reactions are calculated for JP=1/2+- and 3/2+- cases. Through the comparison with the previous measurements at KEK, several quantum numbers are excluded. The…

A narrow resonance peak was observed at 1.54 +/- 0.01 GeV as an exotic baryon with strangeness S = +1 in the gamma + n going to K^+ + K^- + n reaction on Carbon. The new state have a width smaller than 0.025 GeV and a Gaussian significance…

Baryon resonance state with strangeness $S = +1$ observed in systems $p K^0$ and $n K^+$ is interpreted as a result of the decay $N^{*+} \to p \eta$ of the well-known resonance $N^*(1535)$ (with spin-parity $j^P = {1/2}^-$ and mass $m…

If the narrow exotic baryon resonances $\Theta^+(1540)$ and $\Xi_{{3/2}(1862)$ are members of the $J^P = {1/2}1/2^+$ antidecuplet with $N^*(1710)$, the octet-antidecuplet mixing is required not only by the mass spectrum but also by the…

We present two possibilities to determine the P-parity of the pentaquark $\Theta^+$, in a model independent way, via the measurement of polarization observables in $p+p\to \Theta^+ +\Sigma^+$, or $n+p\to \Theta^+ +\Lambda^0$, in the near…

Given presently known empirical information about the exotic Theta+ baryon, we analyze possible properties of its SU(3)F partners, paying special attention to the nonstrange member of the antidecuplet N*. The modified PWA analysis presents…

We propose that the recently discovered \Theta baryon is a bound state of four quarks and an antiquark, containing two highly correlated ud-pairs. If so, the \Theta baryon has positive parity, and it lies in an near-ideally mixed SU(3)_{f}…

The pentaquark $\Theta^+$ has been searched for via the $\pi^-p \to K^-X$ reaction with beam momenta of 1.92 and 2.01 GeV/$c$ at J-PARC. A missing mass resolution of 2 MeV (FWHM) was achieved but no sharp peak structure was observed. The…

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 meson kappa(800)-exchange is also taken into account. In…

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…

We suggest to classify baryon resonances as single-quark states in a mean field, and/or as its collective excitations. Identifying the Roper resonance N(1440), the nucleon resonance N(1535), and the singlet hyperon Lambda(1405) as…

We compute the spectra of exotic pentaquarks and monopole excitations of the low--lying ${1/2}^+$ and ${3/2}^+$ baryons in a chiral soliton model. Once the low--lying baryon properties are fit, the other states are predicted without any…

Recently the so-called $\Theta^+$ resonance has been reported first from SPring8\cite{nakano} and many following experiments showed apparent confirmation of the state. Since $\Theta^+$ exclusively decays into either $K^+ n$ or $K^0 p$, it…

Motivated by the recent discovery of the exotic S=+1 narrow baryon resonance Theta^+ at 1540 MeV, with quark content {uudd sbar}, we conjecture the existence of its anti-charmed analogue Theta_c, with quark content {uudd cbar}, and compute…