Related papers: Study the exotic $\Theta^+$ with polarized photon …
We present an analysis of a Beam-Target double polarization asymmetry in $\gamma n\to \Theta^+ K^-$. We show that this quantity can serve as a filter for the determination of the $\Theta^+$'s spin-parity assignment near threshold. It is…
Spin observables in the photoproduction of the $\Theta^+$ are explored for the purpose of determining the parity of the $\Theta^+$. Based on reflection symmetry in the scattering plane, we show that certain spin observables in the…
We discuss the possibility of determining the parity of the $\Theta^+$ baryon from photoproduction $\gamma N\to K\Theta^+$ process near threshold. We utilize the conservation laws of parity and angular momentum for the analysis of angular…
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.…
We discuss model independent methods to measure the $P$-parity of the $\Theta^+$-pentaquark, in the simplest processes of photoproduction, $\gamma+N\to \bar{K}+\Theta^+$, using definite relations between T-even polarization observables,…
Angular distributions for production of the $\Theta^+$ pentaquark are calculated for the collisions of polarized protons with polarized target protons. We compare calculations based on different assumptions concerning spin and parity…
We present an analysis of the Beam-Target double polarization asymmetry for the photoproduction of $\Theta^+$ in $\gamma n\to \Theta^+ K^-$. We show that this quantity can serve as a filter for the determination of the $\Theta^+$'s…
We study photoproduction reactions for Theta^+, which was recently observed as a candidate of an exotic five quark state uudd(bar s). We employ effective lagrangian interactions in the linear and non-linear formalism of chiral symmetry and…
Spin structure of the reaction ${\vec p}{\vec n}\to {\vec \Lambda^0} {\vec \Theta}$ is analysed at the threshold in a model independent way under assumption that the $\Theta^+$ is an isosinglet. We found that the sign of the spin-spin…
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…
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…
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…
It is demonstrated that measurements of photon asymmetry in the $\gamma n \to K^- K^+ n$ reaction, can most likely determine the parity of the newly discovered $\Theta^+$ pentaquark. We predict that if the parity of $\Theta^+$ is positive,…
We study properties of the pentaquark particle Theta+ with emphasis on the role of chiral symmetry. It is shown that when chiral force is sufficiently strong, the positive parity Theta+ may be realized with a lower mass relative to the…
The photoproduction rate of pentaquark $\Theta^+$ is calculated in a hot and dense medium. At high temperature and density, due to the restoration of chiral symmetry, photoproduction energy threshold is increased. Above the thresold the…
We investigate the production of the pentaquark $\Theta^+$ baryon via the $\gamma n\to K^-\Theta^+$ and $\gamma p\to \bar{K}^0 \Theta^+$ processes, focusing on the parity of the $\Theta^+$. Using the effective Lagrangians, we calculate the…
We compute cross sections of $\Theta^+$ production near threshold for a polarized proton reaction, $\vec p \vec p \to \Sigma^+ \Theta^+$ which was recently proposed to determine unambiguously the parity of $\Theta^+$. Within theoretical…
We present constraints on the {\it relative} photoproduction cross sections of positive parity pentaquark states, $\Sigma_5$, $\Lambda_5$, and $N_5$, based on a minimum phenomenology gained in $\gamma N \to K \Theta^+$ and their…
We reinvestigate the photoproduction of the exotic pentaquark baryon Theta^+(1540,1/2^+) from the gamma N -> Kbar Theta^+ reaction process within the effective Lagrangian approach, taking into account new theoretical information on the…
The photoproduction processes of the exotic $\Theta^+(1540)$ baryon and the $\bar{K}^*$ meson from the nucleon targets, i.e., $\gamma n \to K^{*-} \Theta^+$ and $\gamma p \to \bar{K}^{*0} \Theta^+$, are investigated in a hadronic model. We…