arXiv subjects
Publications and source records attributed to J. Révai.
The first calculation of kaonic deuterium $1s$ level shift using Faddeev-type equations was performed. The obtained results were compared with commonly used approximate approaches.
We strongly doubt the claimed priority of this work as the first full three-body calculation of the considered reaction.
New strong coupled-channel $\bar{K}N - πΣ$ potential, reproducing all existing experimental data and suitable for using in an accurate few-body calculations, is constructed. Isospin breaking effects of direct inclusion of the Coulomb interaction and using of physical masses in calculations are investigated. The $1 s$ level shift and width of kaonic hydrogen, consistent with the scattering data, was obtained and the corresponding exact strong $K^- p$ scattering length was calculated. One- and two-pole form of $Λ(1405)$ resonance was considered.
It is argued, that adjusting strong potentials directly to observed hadronic atom level shifts may lead to significantly different scattering lengths, than those, predicted by the Deser formula. On the example of the 1s level shift of kaonic hydrogen it is demonstrated, that the usually adopted Deser values deduced from the two recent measurements in KEK and by the DEAR Collaboration $a_D({\rm KEK}) = 0.78 - 0.49i$ fm and $a_D({\rm DEAR}) = 0.47 - 0.3i$ fm should be replaced by $a_s({\rm KEK})\simeq 0.85 - 0.62i$ fm and $a_s({\rm DEAR})\simeq 0.49 - 0.35i$ fm, correspondingly.
Coupled-channel three-body calculations of an $I=1/2$, $J^π=0^-$ $\bar{K}NN$ quasi-bound state in the $\bar{K}NN - πΣN$ system were performed and the dependence of the resulting three-body energy on the two-body $\bar{K}N - πΣ$ interaction was investigated. Earlier results of binding energy $B_{K^-pp} \sim 50 -70$ MeV and width $Γ_{K^-pp} \sim 100$ MeV are confirmed [N.V. Shevchenko {\it et al.}, Phys. Rev. Lett. {\bf 98}, 082301 (2007)]. It is shown that a suitably constructed energy-independent complex $\bar{K}N$ potential gives a considerably shallower and narrower three-body quasi-bound state than the full coupled-channel calculation. Comparison with other calculations is made.
A full quantum mechanical calculation of partial cross-sections leading to different final states of antiprotonic helium atom was performed. Calculations were carried out for a wide range of antiprotonic helium states and incident (lab) energies of the antiproton.