English
Related papers

Related papers: Interference and nuclear medium effects on the eta…

200 papers

We study the structure and formation of the $\phi$ mesic nuclei to investigate the in-medium modification of the $\phi$-meson spectral function at finite density. We consider (${\bar p},\phi$), ($\gamma,p$) and ($\pi^-,n$) reactions to…

Nuclear Theory · Physics 2010-12-13 J. Yamagata-Sekihara , D. Cabrera , M. J. Vicente Vacas , S. Hirenzaki

An analysis of incoherent photoproduction of $\eta$ mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the $\gamma$N-$\eta$N amplitude, is described within an isobar model. Effects…

Nuclear Theory · Physics 2009-11-07 A. Sibirtsev , S. Schneider , Ch. Elster , J. Haidenbauer , S. Krewald , J. Speth

The $\gamma p \to \phi \eta p$ reaction is studied in the kinematic region where the $\eta p$ final state originates dominantly from the decay of the N*(1535) resonance. The threshold laboratory photon energy for this reaction (at the peak…

Nuclear Theory · Physics 2008-11-26 Matthias F. M. Lutz , Madeleine Soyeur

We study the $\eta N$ interactions in the hot and dense isospin asymmetric nuclear matter using two different approaches. In the first approach, the in-medium mass and optical potential of $\eta$-meson have been calculated in the chiral…

Nuclear Theory · Physics 2021-01-04 Rajesh Kumar , Arvind Kumar

The inclusive 12C(p,p') and exclusive 12C(p,p'X) reactions have been studied with a beam energy of 156 MeV and for X = p and alpha. The study focuses on the (p,p'X) reaction mechanism and on the structure of 12C just above the…

The self-energy of an eta meson in the nuclear medium is calculated in a chiral unitary approach. A coupled channel Bethe-Salpeter equation is solved to obtain the effective eta-N interaction in the medium. The base model reproduces well…

High Energy Physics - Phenomenology · Physics 2016-09-06 T. Inoue , E. Oset

We studied the effect of cross section on mass asymmetric systems. The mass asymmetry of a reaction can be defined by the asymmetry parameter {\eta} = |(AT - AP)/(AT + AP)|; [1] where AT and AP are the masses of the target and projectile,…

Nuclear Theory · Physics 2011-07-28 Deepinder Kaur , Varinderjit Kaur , Suneel Kumar

The upper limit of the total cross section for quasi-free pn -> pn eta-prime reaction has been determined in the excess energy range near the kinematic threshold. The measurement has been carried out at the COSY-11 detection setup using a…

Nuclear Experiment · Physics 2009-09-25 J. Klaja

The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV…

The isoscalar $\eta$ and $\eta'$ mesons are special in QCD, being linked both to chiral symmetry and to non-perturbative glue associated with the axial anomaly. The properties of these mesons in medium are sensitive to how these dynamics…

High Energy Physics - Phenomenology · Physics 2022-11-15 Steven D. Bass , Volker Metag , Pawel Moskal

The possible existence of $\eta$-mesic nuclei poses an interesting and still open issue of research. Since the occurence of such $\eta$-nucleus bound states is reflected in the corresponding $\eta$-nucleus scattering length, we critically…

Nuclear Theory · Physics 2009-11-10 A. Sibirtsev , J. Haidenbauer , C. Hanhart , J. A. Niskanen

We propose to use the recoilless (d,$^3$He) reaction to produce $\eta$-mesic nuclei. This reaction has been used to observe deeply bound pionic states and proven to be powerful recently. We calculate $\eta$-mesic bound states in the nucleus…

Nuclear Theory · Physics 2011-10-11 R. S. Hayano , S. Hirenzaki , A. Gillitzer

We discuss the possibility to produce the bound states of the $\eta'(958)$ meson in nuclei theoretically. We calculate the formation cross sections of the $\eta'$ bound states with the Green function method for ($\gamma$,p) reaction and…

High Energy Physics - Phenomenology · Physics 2009-11-10 Hideko Nagahiro , Satoru Hirenzaki

A relativistic model for the quasifree exclusive photoproduction of $\eta$ mesons on nuclei is extended to include both non-local and medium effects. The reaction is assumed to proceed via the dominant contribution of the S$_{11}$(1535)…

Nuclear Theory · Physics 2009-11-10 M. Hedayati-Poor , S. Bayegan , H. S. Sherif

With the eta-nucleon (eta N) interaction Lagrangian deduced from chiral perturbation theory, we study the possible eta-mesic nuclei in the framework of relativistic mean-field theory. The eta single-particle energies are sensitive to the…

Nuclear Theory · Physics 2008-11-26 C. Y. Song , X. H. Zhong , L. Li , P. Z. Ning

The nuclear states of \bar K and \eta are bound by a similar mechanism - the excitations of nucleons to \Lambda (1405) and N*(1535) resonant states. The observed large differences in binding energies are understood in terms of separation of…

Nuclear Theory · Physics 2011-04-14 S. Wycech

Interference effect of neutron capture cross section between the compound and direct processes is investigated. The compound process is calculated by resonance parameters and the direct process by the potential mode. The interference effect…

Nuclear Theory · Physics 2017-12-06 Futoshi Minato , Tokuro Fukui

The position and movement of poles of the amplitude for elastic eta-meson scattering off the light nuclei d, t, ^3He, and ^4He are studied. It is found that, within the existing uncertainties for the elementary eta-N interaction, all these…

Nuclear Theory · Physics 2007-05-23 S. A. Rakityansky , S. A. Sofianos , M. Braun , V. B. Belyaev , W. Sandhas

It is shown that the new data on the excitation energy Eex spectrum of the residual nuclear system in the Sigma-hypernuclear region in the reactions (K-,pi+-) on Be-9 and in the reaction (K-,pi+) on He-4 and C-12 can be described without…

Nuclear Theory · Physics 2009-10-31 O. D. Dalkarov , V. M. Kolybasov

In May-June 2014, the experiment devoted to the search for the bound state of the $\eta$ meson and $^3$$He$ nucleus has been performed at COSY accelerator in Research Center J\"ulich in Germany with WASA-at-COSY facility. The excitation…

High Energy Physics - Experiment · Physics 2019-05-22 Oleksandr Rundel