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Related papers: First Observation of the $\Lambda(1405)$ Line Shap…

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We investigate the photoproduction of Lambda(1405,1/2^-) = Lambda* off the proton target using the effective Lagrangian in the Born approximation. We observed that, depending on the choice of the K* N Lambda* coupling strength, the total…

High Energy Physics - Phenomenology · Physics 2011-07-01 Seung-il Nam , Ji-Hyoung Park , Atsushi Hosaka , Hyun-Chul Kim

Recently we presented a successful strategy to extract the position of the two $\Lambda(1405)$ poles from experimental photoproduction data on the $\gamma p \to K^+ \pi^0 \Sigma^0 $ reaction at Jefferson Lab. Following a similar strategy,…

Nuclear Theory · Physics 2015-06-16 L. Roca , E. Oset

Recent CLAS data for the pi Sigma invariant mass distributions (line-shapes) in the gamma p -> K^+ pi Sigma reaction are theoretically investigated. The line-shapes have peaks associated with the Lambda(1405) excitation. Our model consists…

Nuclear Theory · Physics 2014-02-04 S. X. Nakamura , D. Jido

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

The pp -> p K+ Y0 reaction has been studied for hyperon masses m(Y0)<1540 MeV/c2 at COSY-Juelich by using a 3.65 GeV/c circulating proton beam incident on an internal hydrogen target. Final states comprising two protons, one positively…

The reaction $ep \to e'K^+\Lambda(1520)$ with $\Lambda(1520) \to p'K^-$ was studied at electron beam energies of 4.05, 4.25, and 4.46 GeV, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The cos$\theta_{K^+}$,…

High Energy Physics - Experiment · Physics 2010-04-06 S. P. Barrow

Using the CLAS detector system in Hall B at Jefferson Lab, we have done a high statistics measurement of the photoproduction of K+ Lambda(1405) using a proton target. The reconstructed invariant mass seen in the various Sigma pi decay modes…

Nuclear Experiment · Physics 2014-11-20 Kei Moriya , Reinhard Schumacher

We investigate the $\Lambda(1405,1/2^-)\equiv\Lambda^*$ photoproduction off the proton target, i.e. $\gamma p\to K^+\Lambda^*$, considering explicitly its two-pole structure, the higher ($\Lambda^*_H:\,1430\,\mathrm{MeV}$) and lower…

High Energy Physics - Phenomenology · Physics 2015-03-03 Seung-il Nam , Hyun-Kyu Jo

Since the discovery of the $\Lambda(1405)$, it remains poorly described by conventional constituent quark models, and it is a candidate for having an "exotic" meson-baryon or "penta-quark" structure, similar to states recently reported in…

In this work, we perform a \textit{toy-model} analysis for the unpolarized photo- and electroproduction of $\Lambda(1405)\equiv\Lambda^*$ via $\gamma^{(*)}p\to K^+\pi^+\Sigma^-$ by employing the effective Lagrangian approach at the tree…

High Energy Physics - Phenomenology · Physics 2017-11-22 Seung-il Nam

The properties of the $\Lambda(1405)$ resonance have been investigated from radiative decay of $K^- p\to Y\gamma$ and photoproduction $\gamma p\to K^+\Lambda(1405)$ within the framework of the isobar model. For a consistent result with…

Nuclear Theory · Physics 2009-11-03 Tae Keun Choi , Kyung Sik Kim , Byung Geel Yu

We present an analysis of the Lambda(1405) resonance produced in the reaction p+p->Sigma^{pm}+pi^{mp}+K+p at 3.5 GeV kinetic beam energy measured with HADES at GSI. The two charged decay channels Lambda(1405) -> Sigma^{\pm}+pi^{\mp} have…

The $\Lambda(1405)$ resonance production reaction is investigated within the framework of the coupled-channels Alt-Grassberger-Sandhas (AGS) equations. We perform full three-body calculations for the $\bar{K}NN-\pi YN$ amplitudes on the…

Nuclear Theory · Physics 2016-03-08 Shota Ohnishi , Yoichi Ikeda , Tetsuo Hyodo , Wolfram Weise

Exploiting the isobar model, kaon photo- and electroproduction on the proton in the resonance region comes under scrutiny. An upgrade of our previous model, comprising higher-spin nucleon and hyperon exchanges in the consistent formalism,…

Nuclear Theory · Physics 2018-03-02 D. Skoupil , P. Bydžovský

We have carried a theoretical study of the K^- p\to M B \gamma reaction with M B = K^-p, \bar{K}^0 n, \pi^- \Sigma^+, \pi^+ \Sigma^-, \pi^0 \Sigma^0, \pi^0 \Lambda, for K^- lab. momenta between 200 and 500 MeV/c, using a chiral unitary…

Nuclear Theory · Physics 2009-10-31 J. C. Nacher , E. Oset , H. Toki , A. Ramos

Cross section measurements of the exclusive p(e,e'K+)Lambda,Sigma^0 electroproduction reactions have been performed at the Mainz Microtron MAMI in the A1 spectrometer facility using for the first time the Kaos spectrometer for kaon…

Among the light baryons, the $J^\pi = \frac{1}{2}^-$ $\Lambda(1405)$ hyperon is an important special case as it sits just below the $N\bar{K}$ threshold and decays almost exclusively to $\Sigma\pi$. Some long-standing hypotheses for…

Nuclear Experiment · Physics 2022-11-30 Nilanga Wickramaarachchi , Reinhard A. Schumacher , Grzegorz Kalicy

The aim of the present analysis is to determine the relative production cross sections of the $\Lambda$(1405) and $\Sigma(1385)^{0}$ resonances in p+p collisions at E$_{kin}$=3.5 GeV measured with HADES. Upper and lower limits have been…

We present a strategy to extract the position of the two $\Lambda(1405)$ poles from experimental photoproduction data measured recently at different energies in the $\gamma p \to K^+ \pi^0 \Sigma^0 $ reaction at Jefferson Lab. By means of a…

Nuclear Theory · Physics 2013-05-08 L. Roca , E. Oset