Related papers: Determining the $\Theta^+$ quantum numbers through…
We study the $K^+p\to \pi^+K^+n$ reaction with some kinematics suited to the production of the $\Theta^+$ resonance recently observed. We show that, independently of the quantum numbers of the $\Theta^+$, a resonance signal is always…
We study the $K^+p\to \pi^+K^+n$ reaction with some kinematics suited to the production of the $\Theta^+$ resonance recently observed and show that the measurement of cross sections and polarization observables can shed light on the…
We have searched for a bound state of kaon and pion denoted by $X$. The $X$ was conjectured to explain the so-called $\Theta^+$ resonance as a bound state of kaon, pion and nucleon. This model explains almost all properties of the…
In this talk I look into three different topics, addressing first a method to determine the quantum numbers of the $\Theta^+$, then exploiting the possibility that the $\Theta^+$ is a bound state of $K \pi N$ and in the third place I…
We present results on the production of bound states of $\Theta^+$ in nuclei using the $(K^+,\pi^+)$ reaction. By taking into account the states obtained within a wide range of strength of the $\Theta^+$ nucleus optical potential, plus the…
We study $\Theta^+(1540)$ productions in kaon-nucleon ($KN$) and nucleon-nucleon ($NN$) interactions by assuming that the $\Theta^+$ is an isosinglet with $J^P = \frac12^+$. Possible $t$-channel diagrams with $K^*$ exchange are considered…
The cross section for $\Theta^+$ production from the reaction $\gamma p\to\pi^+K^-\Theta^+$, which was observed in the CLAS experiment at the Jefferson National Laboratory, is evaluated in a hadronic model that includes couplings of…
The \gamma d \to K^+K^-pn reaction has been studied to search for the evidence of the \Theta^+ by detecting K^+K^- pairs at forward angles. The Fermi-motion corrected nK^+ invariant mass distribution shows a narrow peak at 1.524 +- 0.002 +…
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…
We estimate the reaction mechanisms for the photoproduction of the Theta^+(1540) resonance on the nucleon, through K and K^* Regge exchanges. We compare the size of the cross sections for the gamma n -> K^- Theta^+ and gamma p -> K^0 bar…
Following a recent suggestion that the $\Theta ^+$ could be a $K \pi N$ bound state we perform an investigation under the light of the meson meson and meson baryon dynamics provided by the chiral Lagrangians and using methods currently…
We investigate the impact of the \Theta^+(1540) resonance on differential and integrated cross sections for the reaction K^+d{\to}K^0pp, where experimental information is available at kaon momenta below 640 MeV/c. The calculation utilizes…
We have searched for $\Theta^{+}$ via $\pi^{-}p \to K^{-}X$ reaction using 1.87 and 1.92 GeV/c $\pi^{-}$ beam at the K2 beam line of the KEK 12 GeV Proton Synchrotron. In the missing mass spectrum at beam momentum of 1.92 GeV/$c$, a bump…
The strength of the kaon--antikaon interaction is a crucial quantity for many physics topics. It is for example, an important parameter in the discussion on the nature of the scalar resonances $a_{0}(980)$ and $f_{0}(980)$, in particular…
We derive, in model independent way, the spin structure of the matrix element for the reaction of associative $\Theta^+$ pentaquark production, $\pi^{\pm}+D\to \Theta^+ +\Sigma^{\pm}, $ in the threshold region and in collinear kinematics.…
The reaction $\gamma p \to pK^+K^-$ was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a $\Theta^{++}$ pentaquark, a narrow doubly charged baryon state having…
The differential and total cross sections for kaon pair production in the pp->ppK+K- reaction have been measured at three beam energies of 2.65, 2.70, and 2.83 GeV using the ANKE magnetic spectrometer at the COSY-Juelich accelerator. These…
We present a calculation of the $\gamma d \to K^+ K^- n p $ reaction with the aim of seeing if the experimental peak observed in the $K^+ n$ invariant mass around 1526 MeV, from where evidence for the existence of the $\Theta^+$ has been…
We investigate Theta^+ production via photon and nucleon induced reactions. We observe that the positive parity Theta^+ production provides about ten times larger total cross sections than those of the negative parity one in both photon and…
We make a study of the (pi^- p --> K^0 pi^0 Lambda), (pi^+ p --> K^+ pi^+ Lambda), (K^+\bar{K}^0 p), (K^+ pi^+ Sigma^0), (K^+ pi^0 Sigma^+), and (eta pi^+ p) reactions, in which the basic dynamics is given by the excitation of the…