相关论文: Photoproduction of the doubly-strange Xi Hyperons
We report on the first measurement of exclusive Xi-(1321) hyperon photoproduction in gamma p --> K+ K+ Xi- for 3.2 < E(gamma) < 3.9 GeV. The final state is identified by the missing mass in p(gamma,K+ K+)X measured with the CLAS detector at…
The doubly-strange Xi baryons provide an effective way to study a puzzle called the missing-baryons problem, where both quark models and lattice gauge theory predict more baryon excited states than are seen experimentally. However, few of…
The E885 collaboration utilized the 1.8 GeV/c K^- beam line at the AGS to accumulate 3 x 10^5 (K^-,K^+) events. Xi hypernuclear states are expected to be produced through the reaction K^- + ^{12}C -> K^+ + ^{12}_{Xi}Be. The measured…
The photoproduction reaction $\gamma N \to K K \Xi$ is investigated based on a relativistic meson-exchange model of hadronic interactions. The production amplitude is calculated in the tree-level approximation from relevant effective…
The exclusive reactions $\gamma p \to K^{*0} \Sigma^+(1189)$ and $\gamma p \to K^{0} \pi^{0}\Sigma^+(1189)$, leading to the p 4$\pi^{0}$ final state, have been measured with a tagged photon beam for incident energies from threshold up to…
Photoproduction of the cascade resonances has been investigated in the reactions $\gamma p \to K^+ K^+ (X)$ and $\gamma p \to K^+ K^+ \pi^- (X)$. The mass split of the $\Xi$ doublet is measured to be $5.4\pm 1.8$ MeV/c$^2$, consistent with…
The search for missing nucleon resonances using coupled channel analysis has mostly been concentrated on $N\pi$ and $KY$ channels, while the contributions of $K^*Y$ and $KY^*$ channels have not been investigated thoroughly mostly due to the…
Within the framework of NRQCD, the photoproduction of doubly heavy baryons $\Xi_{cc}$, $\Xi_{bc}$, $\Xi_{bb}$ and their $P$-wave excited states has been systematically investigated. The production mechanism is that a color anti-triplet or…
Impressive progress achieved in the past decade in experimental studies of exclusive meson photoproduction off protons and global multi-channel amplitude analyses has resulted in the discovery of several long-awaited new nucleon resonances,…
Despite decades of studies of the photoproduction of hyperons, both their production mechanisms and their spectra of excited states are still largely unknown. While the parity-violating weak decay of hyperons offers a means of measuring…
The CLAS Collaboration at Jefferson Lab conducted a photoproduction experiment on a proton target using a tagged photon beam with an energy range of 1.5-3.8 GeV during May-July 2004. With an integrated luminosity of about 75 $pb^{-1}$, this…
We consider the reactions gamma p --> M B, with M B being either K+ Lambda, K+ Sigma0, or Pi n, within a diquark model which is based on perturbative QCD. The model parameters and the quark-diquark distribution amplitudes of the baryons are…
The exclusive reaction $\gamma p \to p K^+ K^-$ was studied in the photon energy range $3.0 - 3.8 \mbox{ GeV}$ and momentum transfer range $0.6<-t<1.3 \mbox{ GeV}^2$. Data were collected with the CLAS detector at the Thomas Jefferson…
The exclusive reaction $\gamma p \to p \pi^+ \pi^-$ was studied in the photon energy range 3.0 - 3.8 GeV and momentum transfer range $0.4<-t<1.0$ GeV$^2$. Data were collected with the CLAS detector at the Thomas Jefferson National…
Based on 334 pb$^{-1}$ of photoproduction data collected with the GlueX detector at Jefferson Lab, we have measured for the first time the cross section of the exclusive reaction $\gamma + p \to \phi(1020) \pi^+\pi^- p$ by reconstructing…
We report the first measurement of the photoproduction cross section of the $\phi$ meson in its neutral decay mode in the reaction $\gamma p \to p\phi(K_SK_L)$. The experiment was performed with a tagged photon beam of energy $1.6 \le…
Indications for the production of a neutral excited hyperon in the reaction pp -> p K^+ Y^{0*} are observed in an experiment performed with the ANKE spectrometer at COSY-J\"ulich at a beam momentum of 3.65 GeV/c. Two final states were…
We report here differential cross sections for the reaction $\gamma p \to K^{*0}\Sigma^+$ for the first time with high statistics. The measurements were done using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were…
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 present an inclusive search for strange pentaquark production in e+e- interactions at a center-of-mass energy of 10.58 GeV using 123 fb-1 of data collected with the BaBar detector. We look for the states that have been reported…