143 citations · 1k across the 39 of their papers we have counts for
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Extraction of baryonia from the lightest anti-protonic atoms
B. Loiseau, S. Wycech
Anti-protonic hydrogen and helium atoms are analyzed. Level shifts and width are expressed in terms of -nucleon sub-threshold scattering lengths and volumes. Experimental…
On Gamov states of hyperons
Slawomir Wycech, Kristian Piscicchia
Both the FINUDA and AMADEUS experiments evidenced a low momentum component when investigating pairs produced in K nuclear capture. This component is interpreted…
Antinucleon-nucleus interaction near threshold from the Paris potential
E. Friedman, A. Gal, B. Loiseau +1
A general algorithm for handling the energy dependence of hadron-nucleon amplitudes in the nuclear medium, consistently with their density dependence, has been recently applied to…
Baryonium, a common ground for atomic and high energy physics
S. Wycech, J. P. Dedonder, B. Loiseau
Indications of the existence of quasi-bound states in the N-Nbar system are presented. Measurements by BES discovered a broad enhancement close to the p-pbar threshold in the S wav…
Search for baryonium and the physics at FAIR
Slawomir Wycech, Jean-Pierre Dedonder, Benoit Loiseau
The existence of nucleon-antinucleon quasi-bound state is indicated in two decay modes of the J/psi meson studied by BES. We discuss an explanation in a fairly traditional Paris-po…
Studies of mesic nuclei via decay reactions
Slawomir Wycech, Wojciech Krzemien
Collisions in a system of two particles at energies close to a bound state in different channels are discussed. Next, the bound state decays into a third coupled channel. A phenome…
K-Mesic Nuclei Versus eta -Mesic Nuclei
S. Wycech
The nuclear states of \bar K and ηare bound by a similar mechanism - the excitations of nucleons to Λ(1405) and N*(1535) resonant states. The observed large differences in binding…
On the structure of the X(1835) baryonium
J. -P. Dedonder, B. Loiseau, B. El-Bennich +1
The measurement by the BES collaboration of J/psi -> gamma p pbar decays indicates an enhancement at the p-pbar threshold. In another experiment BES finds a peak in the invariant m…
Variational calculations for K-few-nucleon systems
S. Wycech, A. M. Green
Deeply bound KNN, KNNN and KNNNN states are discussed. The effective force exerted by the K meson on the nucleons is calculated with static nucleons. Next the binding energies are…
Paris nucleon-antinucleon potential constrained by recent antiprotonic-atom data and antineutron-proton total cross sections
B. El-Bennich, M. Lacombe, B. Loiseau +1
We report on an updated Paris nucleon-antinucleon optical potential. The long- and intermediate-range real parts are obtained by G-parity transformation of the Paris nucleon-nucleo…
Nuclear surface studies with antiprotonic atom X-rays
S. Wycech, F. J. Hartmann, J. Jastrzebski +3
The recent and older level shifts and widths in pbar atoms are analyzed. The results are fitted by an antiproton-nucleus optical potential with two basic complex strength parameter…
The physical interest in kaonic- and antiprotonic-deuterium atoms
S. Wycech, B. Loiseau
Exotic deuterium and helium are discussed. The S, P and D levels of antiprotonic and kaonic atoms are calculated. Absorptive, subthreshold antiproton-nucleon amplitudes are extract…
On the nuclear states of K^- mesons
S. Wycech, A. M. Green
The KNNN bound states recently discovered at KEK are studied. It is shown that the Lambda(1405) and Sigma(1385) resonant states coupled to the KN system may generate an attraction…
eta-Nucleon Scattering Length and Effective Range uncertainties
A. M. Green, S. Wycech
The coupled eta-N, pi-N, gamma-N, 2pi-N system is described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to pi-N-->pi-N, pi-N-->eta-N, gamm…
On eta-pi mixing close to the eta-Helium threshold
A. M. Green, S. Wycech
A K-matrix formalism is used to relate the amplitudes for the three reactions pd --> 3He eta, pi- 3H --> 3He eta and pd --> 3H pi+. Free parameters are fitted to the available expe…
Final state interactions in the eta-d system
S. Wycech, A. M. Green
The eta-deuteron scattering amplitude is calculated with a recent K-matrix model of eta-N interactions. The existence of a narrow virtual state in the eta-deuteron system is inferr…
Optical potentials for the antiproton nucleus interactions
S. Wycech
The nuclear interactions of atomic and low energy antiprotons are studied. Measurements of level shifts and widths in the lightest elements are analyzed and compared with new resul…
Pion-Lambda-Sigma Coupling Extracted from Hyperonic Atoms
B. Loiseau, S. Wycech
The latest measurements of the atomic level width in Sigma-hyperonic Pb atom offer the most accurate datum in the region of low-energy Sigma-hyperon physics. Atomic widths are due…
Uncertainties in the eta-Nucleon Scattering Length and Effective Range
A. M. Green, S. Wycech
The coupled eta-N, pi-N, gamma-N system is described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to pi-N --->pi- N, gamm…
A coupled K-matrix description of the reactions pi+N -> pi+N, pi+N -> eta+N, gamma+N -> pi+N and gamma+N -> eta+N
A. M. Green, S. Wycech
The coupled pi+N, eta+N, gamma+N systems are described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to pi+N -> pi+N, pi+N -> eta+N, gamma+N…
The energies and residues of the nucleon resonances N(1535) and N(1650)
R. A. Arndt, A. M. Green, R. L. Workman +1
We extract pole positions for the N(1535) and N(1650) resonances using two different models. The positions are determined from fits to different subsets of the existing ,…
The Eta-Nucleon Scattering Length and Effective Range
A. M. Green, S. Wycech
The coupled eta N, pi N system is described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to pi N -> pi N, pi N -> eta N and gamma N -> eta…
Antiprotonic studies of nuclear neutron haloes
S. Wycech, J. Skalski, R. Smolanczuk +2
Nuclear capture of antiprotons from atomic states is studied. Partial widths for single nucleon capture events leading to cold residual nuclei are calculated. Recent CERN experimen…
Exotic Atom Formation in External Electric Fields
Jaroslaw Kulpa, Slawomir Wycech
Validity of the coalescence model of exotic atom formation in the ion collisions is studied . An estimate is given for the rates of P state production in the electric fields of the…