Papers by Johann Haidenbauer
Physical review C: Nuclear physics, 1985
We give a modified separable representation of the Paris potential, which is to remedy shortcomin... more We give a modified separable representation of the Paris potential, which is to remedy shortcomings of an earlier parametrization in the 1S0 and 3P0 partial waves. In particular, the present parametrization does not lead to the unphysical bound states at very large negative energies as encountered previously. Still, it provides for a good approximation of the on-shell as well as
Physics Letters B, 1992
It is shown that, due to gross uncertainties in the description of the annihilation interaction d... more It is shown that, due to gross uncertainties in the description of the annihilation interaction dominating the NN scattering process, N/q data cannot determine at present specific features of the short-ranged elastic N~I interaction.
Physical Review C, 1986
... II II II II ceMOMMM cement ~~OMChOW~MChl Oct mt m~ce~chch~ch~Ol Merce ~t ~toOM~~Ch~MOO~~ ~ChC... more ... II II II II ceMOMMM cement ~~OMChOW~MChl Oct mt m~ce~chch~ch~Ol Merce ~t ~toOM~~Ch~MOO~~ ~ChCh~ceChMM~4)egal ~Ch~~ ~ ~ ~ Ch W oOM~e4~oo ~ ~ m ~ ~ e4 m m e4 m e4 ~ W M ~ ~ II II II II II II Il II II II II II II ll II II C4 M W ~ M M g ~ CV Page 4. ...
Physical Review C, 1983
We perform a critical discussion of the efficiency of the Ernst-Shakin-Thaler method for a separa... more We perform a critical discussion of the efficiency of the Ernst-Shakin-Thaler method for a separable approximation of arbitrary two-body interactions by a careful examination of separable S&-D & N-N potentials that were constructed via this method by Pieper. Not only the on-shell properties of these potentials are considered, but also a comparison is made of their off-shell characteristics relative to the Reid soft-core potential. We point out a peculiarity in Pieper s application of the Ernst-Shakin-Thaler method, which leads to a resonantlike behavior of his potential 3SD1D. It is indicated where care has to be taken in order to circumvent drawbacks inherent in the Ernst-Shakin-Thaler separable approximation scheme.
Physical Review C, 1990
Two different approaches for solving three-nucleon scattering are compared. The one relies on sep... more Two different approaches for solving three-nucleon scattering are compared. The one relies on separable subsystem interactions, while the other one can use any two-nucleon potential and solves the three-body integral equations directly. Both approaches are tested in the ...
The European Physical …, 2004
Page 1. DOI 10.1140/epja/i2003-10236-6 Eur. Phys. J. A 22, 293299 (2004) THE EUROPEAN PHYSICAL J... more Page 1. DOI 10.1140/epja/i2003-10236-6 Eur. Phys. J. A 22, 293299 (2004) THE EUROPEAN PHYSICAL JOURNAL A Energy dependence of the Λ/Σ0 production cross-section ratio in pp interactions P. Kowina1,5,a, M. Wolke1 ...
Physical Review C, 2003
It is shown that most of the available data on the pp → ppη reaction, including the invariant mas... more It is shown that most of the available data on the pp → ppη reaction, including the invariant mass distributions in the pp → ppη reaction recently measured at COSY, can be understood in terms of the partial-wave amplitudes involving final pp S and P states and the η meson s-wave.
Acta Physica Polonica Series B
Some features of the NN final state interaction (FSI) and its role in near-threshold meson produc... more Some features of the NN final state interaction (FSI) and its role in near-threshold meson production in NN collisions are investigated using realistic NN potentials. It is shown that the FSI effects should not be factorized from the production amplitude. The issue of the universality of the NN FSI for the production of mesons with different masses is discussed.
Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon... more Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon-nucleon interaction is taken from chiral effective field theory at next-to-leading order with SU(3) symmetric low-energy constants. Furthermore, the underlying nucleon-nucleon interaction is also derived within chiral effective field theory. We present the single-particle potentials of Λ and Σ hyperons in symmetric and asymmetric nuclear matter computed with the continuous choice for intermediate spectra. The results are in good agreement with the empirical information. In particular, our calculation gives a repulsive Σ-nuclear potential and a weak Λ-nuclear spin-orbit force.
Pentaquark 04 - Proceedings of the International Workshop, 2005
Recently several proposals were put forward to determine the parity of narrow baryonic resonances... more Recently several proposals were put forward to determine the parity of narrow baryonic resonances, in particular the Θ + . In these proceedings we will briefly comment on the general problems in this task and then discuss in detail the potential of reactions of the type N N → Θ + Y , where Y denotes a hyperon (either Σ or Λ) and the arrows indicate that a polarized initial state is required. Besides reiterating the model-independent properties of this class of reactions we discuss the physics content of some model calculations.
Nuclear Physics A, 2000
ABSTRACT
The European Physical Journal A, 2015
The existence of baryon-baryon bound states in the strangeness sector is examined in the framewor... more The existence of baryon-baryon bound states in the strangeness sector is examined in the framework of SU(3) chiral effective field theory. Specifically, the role of SU(3) symmetry breaking contact terms that arise at next-to-leading order in the employed Weinberg power counting scheme is explored. We focus on the 1 S0 partial wave and on baryon-baryon channels with maximal isospin since in this case there are only two independent SU(3) symmetry breaking contact terms. At the same time, those are the channels where most of the bound states have been predicted in the past. Utilizing pp phase shifts and Σ + p cross section data allows us to pin down one of the SU(3) symmetry breaking contact terms and a clear indication for the decrease of attraction when going from the N N system to strangeness S = −2 is found, which rules out a bound state for ΣΣ with isospin I = 2. Assuming that the trend observed for S = 0 to S = −2 is not reversed when going to ΞΣ and ΞΞ makes also bound states in those systems rather unlikely.
The possibility to determine the pΛ scattering length from the final-state interaction in the rea... more The possibility to determine the pΛ scattering length from the final-state interaction in the reaction pp → pK + Λ is investigated experimentally. From a transversely polarized measurement, the K + analyzing power (AN ) which, in principle, allows one to extract the spin triplet scattering length is studied. An unexpected energy dependence of the forward/backward symmetric part of AN is found. The influence of N * resonances on the pΛ invariant mass spectrum is investigated by exploiting the large acceptance for the process pp → pK + Λ → pK + pπ − and is found to be the main source of uncertainty for determining the pΛ scattering length.
NSTAR 2007, 2008
ABSTRACT The Jülich meson-exchange model is applied to two-pion production near threshold. The po... more ABSTRACT The Jülich meson-exchange model is applied to two-pion production near threshold. The pole structure of the S11(1650) and the P11(1440) is discussed.
Physical Review D, 2006
The near-threshold enhancement in the pp invariant mass spectrum from the B + →K + pp decay repor... more The near-threshold enhancement in the pp invariant mass spectrum from the B + →K + pp decay reported recently by the BaBar Collaboration is studied within the Jülich NN model. We illustrate that the invariant mass dependence of the pp spectrum close to the threshold can be reproduced by the final state interactions. This explanation is in line with our previous analysis of the pp invariant mass spectrum from the J/Ψ→γpp decay measured by the BES Collaboration. We also comment on a structure found recently in the π + π − η ′ mass spectrum of the radiative J/Ψ decay by the BES Collaboration. In particular we argue that one should be rather cautions in bringing this structure in connection with the enhancement found in the pp invariant mass spectrum or with the existence of NN bound states.
We investigate the impact of the Θ + (1540) resonance on differential and integrated cross sectio... more We investigate the impact of the Θ + (1540) resonance on differential and integrated cross sections for the reaction K + d→K 0 pp, where experimental information is available at kaon momenta below 640 MeV/c. The calculation utilizes the Jülich KN model and extensions of it that include contributions from a Θ + (1540) state with different widths. The evaluation of the reaction K + d→K 0 pp takes into account effects due to the Fermi motion of the nucleons within the deuteron and the final three-body kinematics. We conclude that the available data constrain the width of the Θ + (1540) to be less than 1 MeV.
Topics in Strangeness Nuclear Physics, 2007
Hyperon-nucleon interactions are presented that are derived either in the conventional meson-exch... more Hyperon-nucleon interactions are presented that are derived either in the conventional meson-exchange picture or within leading order chiral effective field theory. The chiral potential consists of one-pseudoscalar-meson exchanges and non-derivative four-baryon contact terms. With regard to meson-exchange hyperon-nucleon models we focus on the new potential of the Jülich group, whose most salient feature is that the contributions in the scalar-isoscalar (σ) and vector-isovector (ρ) exchange channels are constrained by a microscopic model of correlated ππ and KK exchange.
Nucleon-Nucleon and Nucleon-Antinucleon Interactions, 1985
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Papers by Johann Haidenbauer