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Related papers: On the $\Lambda$ to $\Sigma^0$ ratio from proton-p…

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We report on a theoretical study of the pp->p Lambda K+ and pp->p Sigma0 K+ reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state…

Nuclear Theory · Physics 2011-09-15 Ju-Jun Xie , Hua-Xing Chen , E. Oset

Exclusive data on both the elementary kaon and antikaon production channels have been taken at the cooler synchrotron COSY in proton-proton scattering. In the kaon--hyperon production an enhancement by one order of magnitude of the…

We calculate the cross sections for the $p(p,n\pi^{+})p$ and $p(p,p\pi^{0})p$ reactions for proton beam energies near threshold in a covariant one-boson-exchange model, which incorporates the exchange of $\pi$, $\rho$, $\sigma$ and $\omega$…

Nuclear Theory · Physics 2009-10-30 R. Shyam , U. Mosel

Experimental data from the 2m propane bubble chamber for production of $\Lambda$, $K^0_s$ have been used to search of exotic baryon states, in the $K_s^0 p$, $K_s^0 \Lambda$ and $\Lambda p$ decay mode for the reaction p+propane at 10 GeV/c.…

High Energy Physics - Experiment · Physics 2007-05-23 P. Zh. Aslanyan

We study the production of hyperon resonances in the $p\bar{p}\to\bar{\Lambda}\Sigma\eta$ reaction within an effective Lagrangian approach. The model includes the production of $\Sigma(1750)$ and $\Lambda(1670)$ in the intermediate state…

High Energy Physics - Phenomenology · Physics 2024-11-13 Aojia Xu , Ruitian Li , Xuan Luo , Hao Sun

We have measured inclusive data on $K^+$-meson production in $pp$ collisions at COSY J\"ulich close to the hyperon production threshold and determined the hyperon-nucleon invariant mass spectra. The spectra were decomposed into three parts:…

The $\Lambda(1520)$ resonance has been recently studied in a unitarized coupled channel formalism with $\pi\Sigma(1385)$, $K\Xi(1530)$, $\bar{K}N$ and $\pi\Sigma$ as constituents blocks. We provide a theoretical study of the predictions of…

Nuclear Theory · Physics 2009-11-11 L. Roca , C. Hanhart , E. Oset , Ulf-G. Meißner

The pp -> ppK+K- reaction was measured below the phi threshold at a beam energy of 2.568 GeV using the COSY-ANKE magnetic spectrometer. By assuming that the four-body phase space is distorted only by the product of two-body final state…

The $\gamma p \to K^+ \pi^0 \Lambda$ and $\gamma p \to K^+ \pi \Sigma $ reactions are studied in the kinematic region where the $\pi^0 \Lambda$(1116) and $\pi\Sigma$(1192) pairs originate dominantly from the decay of the $\Sigma$(1385) and…

Nuclear Theory · Physics 2010-12-16 Matthias F. M. Lutz , Madeleine Soyeur

The $\Lambda p \to \Lambda p \pi^0$ reaction near threshold is studied within an effective Lagrangian method. The production process is described by single-pion and single-kaon exchange. In addition to the role played by the…

Nuclear Theory · Physics 2014-11-19 Ju-Jun Xie , Jia-Jun Wu , Bing-Song Zou

We study for the first time the $p\Sigma^-\to K^-d$ and $K^-d\to p\Sigma^-$ reactions close to threshold and show that they are driven by a triangle mechanism, with the $\Lambda(1405)$, a proton and a neutron as intermediate states, which…

Nuclear Theory · Physics 2022-11-30 Albert Feijoo , Raquel Molina , Lian Rong Dai , Eulogio Oset

The particle production and their ratios for $\pi$, $K$, $p$, and $\Lambda$ are studied in Pb + Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV based on a blast-wave model with thermal equilibrium mechanism. The transverse momentum spectra of…

Nuclear Theory · Physics 2014-04-02 S. Zhang , L. X. Han , Y. G. Ma , J. H. Chen , C. Zhong

We present here some results supporting the nature of the $\Lambda(1405)$ resonance as dynamically generated from the meson baryon interaction in coupled channels and resulting from the superposition of two close-by poles. We find support…

Nuclear Theory · Physics 2015-05-13 E. Oset , L. S. Geng , M. Döring

We calculate the shape of the $\pi\Sigma$ and $\bar K N$ invariant mass distributions in the $\Lambda_b \to J/\psi\, \pi\Sigma$ and $\Lambda_b \to J/\psi \,\bar K N$ decays that are dominated by the $\Lambda(1405)$ resonance. The weak…

High Energy Physics - Phenomenology · Physics 2015-06-02 Luis Roca , Maxim Mai , Eulogio Oset , Ulf-G. Meißner

High-statistics cross sections for the reactions gamma + p --> K^+ + Lambda and gamma + p --> K^+ + Sigma^0 have been measured using CLAS at Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 < cos…

Nuclear Experiment · Physics 2019-08-14 R. Bradford , R. A. Schumacher , J. W. C. McNabb , L. Todor

A comprehensive analysis of all available data on cross sections and spin-dependent observables for the $\gamma p \to K^+ \Sigma^0(1385)$, $\gamma n \to K^+ \Sigma^-(1385)$, and $\pi^+ p \to K^+ \Sigma^+(1385)$ reactions is performed within…

High Energy Physics - Phenomenology · Physics 2025-03-21 Ai-Chao Wang , Neng-Chang Wei , Fei Huang

We investigate the exclusive proton-induced $K^+$ production near the kaon threshold. Compared are two models: a meson-exchange model, which includes $\pi$, \rho$, $K$ and $K^\ast$ exchange, together with the dominant baryon resonances, and…

Nuclear Theory · Physics 2011-03-17 Frieder Kleefeld , Fernando Pilotto , Manfred Dillig

We investigate the $K^- p \to \gamma \Sigma$ reaction using an effective Lagrangian approach within an isobar model framework. The model includes contributions from $s$-channel hyperon and hyperon resonance, $t$-channel $K$ and $K^*$,…

High Energy Physics - Phenomenology · Physics 2025-11-18 Yi Pan , Bo-Chao Liu

The pp -> pp eta and pp -> pLambda K^+ reactions near threshold are dominated by the first and second S_11 resonance respectively. It is shown that a one-pion-exchange model exciting these isobars reproduces well the ratio of the production…

Nuclear Theory · Physics 2015-06-26 Goran Faldt , Colin Wilkin