scholarly journals STUDY OF THE K+K- INTERACTION AT COSY-11

2011 ◽  
Vol 26 (03n04) ◽  
pp. 539-541 ◽  
Author(s):  
MICHAŁ SILARSKI

In this article we present studies of the near threshold pp → ppK+K- reaction in view of the K+K- final state interaction. The investigations include analysis of both the low-energy K+K- invariant mass distributions measured by COSY-11 collaboration at excess energies of Q = 10 MeV and Q = 28 MeV and the near threshold excitation function for the pp → ppK+K- reaction. As a result of these studies we have estimated the K+K- scattering length more precise compared to the previous analysis based only on the analysis of the differential cross sections.

2009 ◽  
Vol 18 (05n06) ◽  
pp. 1271-1281 ◽  
Author(s):  
B. K. JAIN ◽  
N. J. UPADHYAY ◽  
K. P. KHEMCHANDANI ◽  
N. G. KELKAR

We present a study of the η production at low energies in pd collision with 3He and pd nuclear systems in the final state. The η production mechanism is described by a two-step model and the final state interactions are included fully. The η - d and η - 3He final state interactions are incorporated through the solution of the Lippmann Schwinger equation for a half off-shell η - AT-matrix. For η - d this t -matrix is written in a factorized form, with an off-shell form factor multiplying an on-shell part having the scattering length representation. The p - d final state interaction is included by multiplying the production matrix element by the inverse of the Jost function which includes the strong as well as the Coulomb interaction. The total cross sections are found to be strongly affected by both the η - d and the p - d final state interactions. The η - 3HeT-matrix is obtained in the Finite Rank Approximation (FRA) by solving few-body equations. The calculated total cross sections are in good accord with the available experimental data. Through the time delay method of Wigner, we also explore the possibility of the existence of quasi-bound η-3 He mesic states in this η - 3He T -matrix. We find that the T -matrix which reproduces the low energy pd → 3He η data implies a quasi-bound eta state near threshold. This is in accord with experimental indications.


2009 ◽  
Vol 24 (29) ◽  
pp. 2319-2329 ◽  
Author(s):  
N. J. UPADHYAY ◽  
B. K. JAIN ◽  
K. P. KHEMCHANDANI ◽  
N. G. KELKAR

A model for the p d→p dη reaction published earlier, including the final state interaction (FSI) of all particles, is revisited to investigate the low energy data on this reaction. The three-body problem of p–d–η scattering in the final state is approximated in terms of pairwise interactions between the three particles in the final state. Apart from a comparison with some preliminary data, two new findings relevant to the near threshold data analysis are reported. The first one points toward the limitations of an FSI factor used conventionally to extract the eta-deuteron scattering length and infer subsequently on the existence of eta-mesic states. The second result emphasizes the role of the p–d FSI and the strong Coulomb repulsion near threshold. Finally, a comparison of the above model calculation with low energy data, excludes very large eta-nucleon scattering lengths.


2020 ◽  
Vol 29 (08) ◽  
pp. 2050056
Author(s):  
E. M. Darwish ◽  
H. M. Al-Ghamdi

Incoherent [Formula: see text]-photoproduction on the deuteron is investigated for photon energies near threshold with particular focus on beam-target double spin asymmetries. The analysis is based on a [Formula: see text] reaction model in which realistic elementary amplitudes for [Formula: see text], [Formula: see text] and [Formula: see text] are incorporated. Numerical results on all possible beam-target double spin asymmetries of the differential and total cross-sections in the photon energy region near threshold are presented. Effects of [Formula: see text] and [Formula: see text] final-state interactions are investigated and their roles are found to be important.


2005 ◽  
Vol 20 (02n03) ◽  
pp. 643-645 ◽  
Author(s):  
H.-H. ADAM ◽  
A. KHOUKAZ ◽  
N. LANG ◽  
T. LISTER ◽  
R. SANTO ◽  
...  

Measurements on the η meson production in proton-deuteron collisions have been performed using the COSY-11 facility at COSY (Jülich). Here we present preliminary results on total and differential cross sections for the pd→3 He η reaction at five excess energies between Q=5.1 and Q=40.6 MeV. The obtained angular distributions for the emitted η mesons in the center of mass system expose a transition from an almost isotropic emission to a highly anisotropic distribution. The extracted total cross sections support a strong η-3 He final state interaction and will be compared with model predictions.


2020 ◽  
Vol 56 (9) ◽  
Author(s):  
Gábor Balassa ◽  
György Wolf

Abstract In this work, we extended our statistical model with charmed and bottomed hadrons, and fit the quark creational probabilities for the heavy quarks, using low energy inclusive charmonium and bottomonium data. With the finalized fit for all the relevant types of quarks (up, down, strange, charm, bottom) at the energy range from a few GeV up to a few tens of GeV’s, the model is now considered complete. Some examples are also given for proton–proton, pion–proton, and proton–antiproton collisions with charmonium, bottomonium, and open charm hadrons in the final state.


1999 ◽  
Vol 14 (03) ◽  
pp. 223-230 ◽  
Author(s):  
O. V. SELYUGIN

A possibility to obtain restrictions of the magnitude of the elastic spin-flip hadron scattering amplitude from accurately measured experimental data on the differential cross-sections of elastic hadron–hadron scattering is shown. Appropriate estimations confirm the previous analysis of experimental data at [Formula: see text] GeV and a probable contribution of the hadron spin-flip amplitude.


Sign in / Sign up

Export Citation Format

Share Document