Publications (117)
The Onset of Color Transparency in Reactions on Nuclei
N. N. Nikolaev, A. Szczurek, J. Speth +3
Quantum filtering of the ejectile wave packet from hard scattering on bound nucleons puts stringent constraints on the onset of color transparency in reactions in nu…
Coherent photoproduction from nuclei and properties in nuclear matter
A. Sibirtsev, Ch. Elster, J. Speth
The coherent -meson photoproduction from nuclei is proposed as a phenomenological method to evaluate the momentum dependence of -meson mass shift and width in nuclear matte…
Dynamics of competition between collectivity and noise in the stock market
S. Drozdz, F. Gruemmer, F. Ruf +1
Detailed study of the financial empirical correlation matrix of the 30 companies comprised by DAX within the period of the last 11 years, using the time-window of 30 trading days,…
Exclusive high- electroproduction: light-cone wave functions and electromagnetic form factors of mesons,
J. Speth, V. R. Zoller
We apply the light-cone technique to electroproduction reaction long considered as a means of measuring the electromagnetic form factor of the pion. We show that the…
Polarization phenomena in the reaction NN to NNpi near threshold
C. Hanhart, J. Haidenbauer, O. Krehl +1
First calculations for spin-dependent observables of the reactions , and near threshold are presented, employing the Jülich model for…
eta' meson production in proton-proton collisions
K. Nakayama, H. F. Arellano, J. W. Durso +1
The pp -> pp eta' reaction is investigated within a relativistic meson-exchange model of hadronic interactions. We explore the role of nucleonic and mesonic, as well as the N* reso…
Threshold meson production in nucleon-nucleon collisions
J. Haidenbauer, Ch. Hanhart, J. Speth
A brief overview on recent model calculations for near threshold pion production in nucleon-nucleon collisions is given. Results from our own investigations of the reactions $pp \r…
Calculations of the isoscalar giant monopole resonance within the self-consistent RPA and its extensions
V. Tselyaev, S. Krewald, E. Litvinova +1
The strength distributions of the isoscalar giant monopole resonance have been calculated in O, Ca, Zr, Sn, Sm, and Pb nuclei withi…
On the missing momentum dependence of the color transparency effects in (e,e'p) scattering
O. Benhar, S. Fantoni, N. N. Nikolaev +3
We explore the missing momentum dependence of the CT effects in quasielastic (e,e'p) scattering. We develop the coupled-channel multiple-scattering theory (CCMST) description of fi…
Pseudovector vs. pseudoscalar coupling in one-boson exchange NN potentials
G. Caia, J. W. Durso, Ch. Elster +3
We examine the effects of pseudoscalar and pseudovector coupling of the pi and eta mesons in one-boson exchange models of the NN interaction using two approaches: time-ordered pert…
Optimizing phonon space in the phonon-coupling model
V. Tselyaev, N. Lyutorovich, J. Speth +1
We present a new scheme to select the most relevant phonons in the phonon-coupling model, named here time-blocking approximation (TBA). The new criterion, based on the phonon-nucle…
Final state interactions in He(e,ep)H at large proton energy
O. Benhar, N. N. Nikolaev, J. Speth +2
At large proton energy, the final state interactions of the knocked out nucleon in $\eep$ reactions off nuclear targets can be described within the eikonal approximation, treating…
Pion Content of the Nucleon as seen in the NA51 Drell-Yan experiment
H. Holtmann, N. N. Nikolaev, J. Speth +1
In a recent CERN Drell-Yan experiment the NA51 group found a strong asymmetry of and densities in the proton at . We interpret this result as a decis…
Aspects of a0-f0 mixing in the reaction pn->da0
A. E. Kudryavtsev, V. E. Tarasov, J. Haidenbauer +2
Some aspects of a0-f0 mixing effects in the reaction with perpendicular polarized proton beam are discussed. An angular--asymmetry parameter is defined t…
What is the structure of the Roper resonance?
O. Krehl, C. Hanhart, S. Krewald +1
We investigate the structure of the nucleon resonance N^*(1440) (Roper) within a coupled-channel meson exchange model for pion-nucleon scattering. The coupling to pipiN states is r…
Theoretical Interpretation of the NE18 Experiment on Nuclear Transparency in A(e,e'p) Scattering
N. N. Nikolaev, A. Szczurek, J. Speth +3
The spectral function, measured in reactions, is distorted by the final-state interaction of the struck proton with the residual nucleus. This causes a broadening of the…
Meson-Exchange Model for the YN Interaction
J. Haidenbauer, W. Melnitchouk, J. Speth
We report on progress in the development of a microscopic model for the hyperon-nucleon interaction within the meson-exchange framework, which incorporates both one-meson as well a…
On the Migdal-Watson approach to FSI effects in meson production in NN collisions
V. Baru, A. M. Gasparian, J. Haidenbauer +2
The influence of the nucleon-nucleon final state interaction (FSI) on properties of the meson production amplitude near threshold is discussed. For the nucleon-nucleon interaction…
Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in Coherent Photo- and Electroproduction: Coupled Channel Analysis
N. N. Nikolaev, J. Speth, B. G. Zakharov
We study medium modifications of the dilepton mass spectrum in coherent photo- and electroproduction of the Rho(1S)- and Rhoprim(2S)-meson resonances on nuclear targets. The analys…
Electric and Magnetic Moments and Transition Probabilities in Pb Nuclei
V. Tselyaev, N. Lyutorovich, J. Speth +3
We present moments and transition probabilities in the neighboring odd-mass nuclei of Pb calculated fully self-consistently from the s.p. properties of Pb with pola…
Leading proton spectrum from DIS at HERA
A. Szczurek, N. N. Nikolaev, J. Speth
The QCD hardness scale for secondary particles () production in semi-inclusive deep inelastic scattering (DIS), , gradually decreases from , the photon vi…
Log-periodic self-similarity: an emerging financial law?
S. Drozdz, F. Grummer, F. Ruf +1
A hypothesis that the financial log-periodicity, cascading self-similarity through various time scales, carries signatures of a law is pursued. It is shown that the most significan…
Microscopic description of the pygmy and giant electric dipole resonances in stable Ca isotopes
G. Tertychny, V. Tselyaev, S. Kamerdzhiev +5
The properties of the pygmy (PDR) and giant dipole resonance (GDR)in the stable , and isotopes have been calculated within the \emph{Extended Theory of…
Correlated $\bbox{ÏÏ}$ Exchange in the $\bbox{NN}$ Interaction
G. Janssen, K. Holinde, J. Speth
We evaluate the contribution to the nucleon-nucleon interaction due to correlated exchange in the , , and / channels by means of dispersion-theoretic metho…
Glauber theory of final-state interactions in scattering
N. N. Nikolaev, J. Speth, B. G. Zakharov
We develop the Glauber theory description of final-state interaction (FSI) in quasielastic scattering. The important new effect is an interaction between the two traject…
From soft to hard regime in elastic pion-pion scattering above resonances
A. Szczurek, N. N. Nikolaev, J. Speth
We discuss the onset of the dominance of the Glauber-Gribov-Landshoff (GGL) component of pQCD hard two-gluon (2G) exchange contribution to hard elastic scattering at moderat…
Collectivity Embedded in Complex Spectra of Finite Interacting Fermi Systems: Nuclear Example
S. Drozdz, S. Nishizaki, J. Speth +1
The mechanism of collectivity coexisting with chaos in a finite system of strongly interacting fermions is investigated. The complex spectra are represented in the basis of two-par…
Final state interactions and correlations: are the latter observable?
A. Bianconi, S. Jeschonnek, N. N. Nikolaev +2
Are effects of short range correlations in the ground state of the target nucleus (initial state correlations ISC) observable in experiments on quasielastic scattering a…
Do the E866 Drell Yan data change our picture of the chiral structure of the nucleon ?
N. N. Nikolaev, W. Schäfer, A. Szczurek +1
We revisit the evaluation of the pionic mechanism of the -asymmetry in the proton structure function. Our analysis is based on the extended AGK unitarity relation…
Extended Theory of Finite Fermi Systems (Collective Vibrations in Closed Shell Nuclei)
S. Kamerdzhiev, J. Speth, G. Tertychny
We review an extension of Migdal's Theory of Finite Fermi Systems which has been developed and applied to collective vibrations in closed shell nuclei in the past ten years. This m…
A meson exchange model for the YN interaction
J. Haidenbauer, W. Melnitchouk, J. Speth
We present a new model for the hyperon-nucleon (Lambda N, Sigma N) interaction, derived within the meson exchange framework. The model incorporates the standard one boson exchange…
Financial multifractality and its subtleties: an example of DAX
A. Z. Gorski, S. Drozdz, J. Speth
Detailed study of multifractal characteristics of the financial time series of asset values and of its returns is performed using a collection of the high frequency Deutsche Aktien…
Glauber theory of initial- and final-state interactions in (p,2p) scattering
O. Benhar, S. Fantoni, N. N. Nikolaev +3
We develop the Glauber theory description of initial- and final-state interactions (IFSI) in quasielastic A(p,2p) scattering. We study the IFSI-distortion effects both for the incl…
Photoproduction of the Eta Meson from the Deuteron Near Threshold
Ch. Elster, A. Sibirtsev, S. Schneider +3
Very recent data for the reaction gamma{d} --> eta{np} are analyzed within a model that includes contributions from the impulse approximation and next order corrections due to the…
The reaction near threshold
C. Hanhart, J. Haidenbauer, A. Reuber +2
We perform a momentum-space calculation of the reaction near threshold. Direct production and pion rescattering are taken into account. For the latter a T-m…
Eta-N Final State Interaction in incoherent Photoproduction of Eta-mesons from the Deuteron near Threshold
A. Sibirtsev, S. Schneider, Ch. Elster +3
An analysis of incoherent photoproduction of mesons off the deuteron for photon energies from threshold to 800 MeV is presented. The dominant contribution, the N-N amp…
The reactions and at threshold: The role of the isoscalar scattering amplitude
C. Hanhart, J. Haidenbauer, M. Hoffmann +2
We examine the role of the elementary isoscalar pion--nucleon scattering amplitude in the description of the processes and at threshold. We argue that…
Correlated and exchange in the baryon-baryon interaction
A. Reuber, K. Holinde, H. -C. Kim +1
A dynamical model for correlated two-pion and two-kaon exchange in the baryon- baryon interaction is presented, both in the scalar-isoscalar () and the vector-isovector ()…
Eta and eta-prime meson production in the reaction pn -> dM near threshold
V. Yu. Grishina, L. A. Kondratyuk, M. Buescher +3
The two-step model with pi-, rho- and omega- exchanges taken into account is applied to investigate the reactions pn -> d eta and pn -> d eta-prime. The existing experimental data…
Semi-inclusive production of pions in DIS and asymmetry
V. Uleshchenko, A. Szczurek, J. Speth
We discuss the role of some nonpartonic effects which lead to and and may therefore modify the conclusionon the $\bar d - \b…
Mapping the proton unintegrated gluon distribution in dijets correlations in real and virtual photoproduction at HERA
A. Szczurek, N. N. Nikolaev, W. Schäfer +1
We discuss how the dijet azimuthal correlations in DIS and real photoproduction at HERA probe the differential (unintegrated) gluon distribution in the proton. We find a strong dep…
On the determination of double diffraction dissociation cross section at HERA
H. Holtmann, N. N. Nikolaev, A. Szczurek +2
The excitation of the proton into undetected multiparticle states (double diffraction dissociation) is an important background to single diffractive deep-inelastic processes $ep \r…
Time scales involved in market emergence
J. Kwapien, S. Drozdz, J. Speth
In addressing the question of the time scales characteristic for the market formation, we analyze high frequency tick-by-tick data from the NYSE and from the German market. By usin…
Exclusive and semi-inclusive strangeness and charm production in and reactions
A. M. Gasparyan, V. Yu. Grishina, L. A. Kondratyuk +2
Using the Quark-Gluon Strings Model (QGSM) combined with Regge phenomenology we consider the reactions and which are dominated by the co…
The longitudinal asymmetry of the missing momentum distribution as a signal of color transparency
O. Benhar, S. Fantoni, N. N. Nikolaev +3
We use multiple scattering theory to evaluate the dependence of the forward-backward asymmetry, , of the missing momentum distribution in quasielstic scat…
Flavour and Spin of the Proton and the Meson Cloud
H. Holtmann, A. Szczurek, J. Speth
We present a complete set of formulas for longitudinal momentum distribution functions (splitting functions) of mesons in the nucleon. It can be applied in the framework of convolu…
What does `rho-exchange' in piN scattering mean?
O. Krehl, C. Hanhart, S. Krewald +1
We present an alternative method for calculating amplitudes for correlated pi pi exchange in the ``sigma'' and rho channel in piN scattering. Starting from a fixed mass meson excha…
Towards identifying the world stock market cross-correlations: DAX versus Dow Jones
S. Drozdz, F. Gruemmer, F. Ruf +1
Effects connected with the world globalization affect also the financial markets. On a way towards quantifying the related characteristics we study the financial empirical correlat…
Self-consistency in the phonon space of the particle-phonon coupling model
V. Tselyaev, N. Lyutorovich, J. Speth +1
In the paper the non-linear generalization of the time blocking approximation (TBA) is presented. The TBA is one of the versions of the extended random-phase approximation (RPA) de…
Dynamics of correlations in the stock market
S. Drozdz, F. Gruemmer, F. Ruf +1
Financial empirical correlation matrices of all the companies which both, the Deutsche Aktienindex (DAX) and the Dow Jones comprised during the time period 1990-1999 are studied us…
On the structure of the scalar mesons and
G. Janssen, B. C. Pearce, K. Holinde +1
We investigate the structure of the scalar mesons and within realistic meson-exchange models of the and interactions. Starting from a modified v…
Testing the meson cloud in the nucleon in Drell-Yan processes
A. Szczurek, M. Ericson, H. Holtmann +1
We discuss the present status of the \bar u-\bar d asymmetry in the nucleon and analize the quantities which are best suited to verify the asymmetry. We find that the Drell-Yan asy…
Skyrme RPA for nuclear resonances: trouble with magnetic modes
J. Speth, P. -G. Reinhard, V. Tselyaev +1
We discuss major differences between electric and magnetic excitations in nuclei appearing in self-consistent calculation based on Skyrme energy-density functionals. Tools of analy…
Extended Theory of Finite Fermi Systems: Application to the collective and non-collective E1 strength in Pb
V. Tselyaev, J. Speth, F. Gruemmer +4
The Extended Theory of Finite Fermi Systems is based on the conventional Landau-Migdal theory and includes the coupling to the low-lying phonons in a consistent way. The phonons gi…
Role of Meson-Meson Correlation Effects in the $\NNb\toÏÏ$ Annihilation Process
V. Mull, G. Janssen, J. Speth +1
Meson-meson correlation effects are investigated in the $\NNb\toÏÏ$ annihilation process using a realistic meson-exchange model for the interaction determined previously,…
asymmetry and semi-inclusive production of pions in DIS
A. Szczurek, V. Uleshchenko, J. Speth
We investigate unambiguities in the extraction of the asymmetry from semi-inclusive production of pions in DIS. The role of several effects beyond the quark-parto…
Role of correlated two-pion exchange in scattering
M. Hoffmann, J. W. Durso, K. Holinde +2
A dynamical model for S-- and P--wave correlated (and ) exchange between a kaon and a nucleon is presented, starting from corresponding $N \bar N \rightarrow K \ba…
A dynamical model for correlated two-pion-exchange in the pion-nucleon interaction
C. Schütz, J. W. Durso, K. Holinde +2
A microscopic model for the process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical informati…
Self-consistent calculations within the Green's function method including particle-phonon coupling and the single-particle continuum
N. Lyutorovich, J. Speth, A. Avdeenkov +4
The Green's function method in the \emph{Quasiparticle Time Blocking Approximation} is applied to nuclear excitations in Sn and Pb. The calculations are performed s…
M1 resonance in Pb within the self-consistent phonon-coupling model
V. Tselyaev, N. Lyutorovich, J. Speth +1
The main goal of the paper is to investigate theoretically the experimentally observed fragmentation of the isovector resonance in Pb within a self-consistent model ba…
Excitation spectra of exotic nuclei in a self-consistent phonon-coupling model
N. Lyutorovich, V. Tselyaev, J. Speth +1
We explore giant resonance spectra and low-lying dipole strength in the Ni and Sn chains from proton rich to very neutron rich isotopes, relevant in astrophysical reaction chains.…
Decomposing the stock market intraday dynamics
J. Kwapien, S. Drozdz, F. Gruemmer +2
The correlation matrix formalism is used to study temporal aspects of the stock market evolution. This formalism allows to decompose the financial dynamics into noise as well as in…
Photoproduction of eta-prime-mesons from the Proton
A. Sibirtsev, Ch. Elster, S. Krewald +1
The presently available data for the reaction are analyzed in terms of a model in which the dominant production mechanism is the exchange of the vector meson…
Quantifying dynamics of the financial correlations
S. Drozdz, J. Kwapien, F. Gruemmer +2
A novel application of the correlation matrix formalism to study dynamics of the financial evolution is presented. This formalism allows to quantify the memory effects as well as s…
The phonon-coupling model for Skyrme forces
N. Lyutorovich, V. Tselyaev, J. Speth +2
A short review on the self-consistent RPA based on a energy-density functional of the Skyrme type is given. We also present an extension of the RPA where the coupling of phonons to…
How to extract the scattering length from production reactions
A. Gasparyan, J. Haidenbauer, C. Hanhart +1
A dispersion integral is derived that allows one to relate directly (spin dependent) invariant mass spectra, measured in a large-momentum transfer reaction such as $pp\to K^+…
Pion-nucleon scattering in a meson-exchange model
A. M. Gasparyan, J. Haidenbauer, C. Hanhart +1
The pi-N interaction is studied within a meson-exchange model and in a coupled-channels approach which includes the channels pi-N, eta-N, as well as three effective pi-pi-N channel…
Incoherent Eta Photoproduction from the Deuteron near Threshold
A. Sibirtsev, S. Schneider, Ch. Elster +3
Very recent data for the reaction gamma+d ->eta np, namely total cross sections, angular and momentum spectra, are analyzed within a model that includes contributions from the impu…
-meson production in proton-proton collisions
K. Nakayama, J. W. Durso, J. Haidenbauer +2
The production of -mesons in proton-proton collisions is investigated within a relativistic meson-exchange model of hadronic interactions. The experimental prerequisites for ex…
Prediction oriented variant of financial log-periodicity and speculating about the stock market development until 2010
S. Drozdz, F. Gruemmer, F. Ruf +1
A phenomenon of the financial log-periodicity is discussed and the characteristics that amplify its predictive potential are elaborated. The principal one is self-similarity that o…
Predicitions for high-energy real and virtual photon-photon scattering from color dipole BFKL-Regge factorization
N. N. Nikolaev, J. Speth, V. R. Zoller
High-energy virtual photon-virtual photon scattering can be viewed as interaction of small size color dipoles from the beam and target photons, which makes $γ^{*}γ^{*}, γ^{*}γ$…
Perturbative QCD versus pion exchange and hadronic FSI effects in the gamma gamma --> pi^+ pi^- reaction
A. Szczurek, J. Speth
The interplay of pQCD, pion exchange and FSI effects is studied for the gamma gamma --> pi^+ pi^- reaction in the region of 2 GeV < W_{gamma gamma} < 6 GeV. We find strong interfer…
Incoherent Photoproduction of -mesons from the Deuteron near Threshold
A. Sibirtsev, Ch. Elster, J. Haidenbauer +1
Incoherent photoproduction of the -meson on the deuteron is studied for photon energies from threshold to 800 MeV. The dominant contribution, the N-N amplitude, is desc…
Phase-Space Exploration in Nuclear Giant Resonance Decay
S. Drozdz, S. Nishizaki, J. Speth +1
The rate of phase-space exploration in the decay of isovector and isoscalar giant quadrupole resonances in Ca is analyzed. The study is based on the time dependence of the s…
Near threshold Lambda and Sigma production in pp collisions
A. M. Gasparian, J. Haidenbauer, C. Hanhart +2
A model calculation for the reactions and near their thresholds is presented. It is argued that the experimentally observed strong suppression of …
Production of -mesons in proton-proton collisions
K. Nakayama, A. Szczurek, C. Hanhart +2
The production of -mesons in proton-proton collisions for proton incident energies up to 2.2 GeV is investigated within a meson-exchange model of hadronic interactions. We find…
Identifying Complexity by Means of Matrices
S. Drozdz, J. Kwapien, J. Speth +1
Complexity is an interdisciplinary concept which, first of all, addresses the question of how order emerges out of randomness. For many reasons matrices provide a very practical an…
M1 Resonances in Unstable Magic Nuclei
S. Kamerdzhiev, J. Speth, G. Tertychny +1
Within a microscopic approach which takes into account RPA configurations, the single-particle continuum and more complex configurations isoscalar and isovecto…
Low-energy M1 excitations in Pb and the spin channel of the Skyrme energy-density functional
V. Tselyaev, N. Lyutorovich, J. Speth +2
We investigate the spin dependent part of the Skyrme energy-density functional, in particular its impact on the residual particle-hole interaction in self-consistent calculations o…
Landau-Migdal vs. Skyrme
J. Speth, S. Krewald, F. Grümmer +3
The magnitude and density-dependence of the non-spin dependent Landau-Migdal parameters are derived from Skyrme energy functionals and compared with the phenomenological ones. We p…
Strange vector currents and the OZI-rule
Ulf-G. MeiÃner, V. Mull, J. Speth +1
We investigate the role of correlated exchange in the extraction of matrix elements of the strange vector current in the proton. We show that a realistic isoscalar spectral…
The color dipole BFKL-Regge expansion: from DIS on protons to pions to rise of hadronic cross sections
N. N. Nikolaev, J. Speth, V. R. Zoller
As noticed by Fadin, Kuraev and Lipatov in 1975 incorporation of asymptotic freedom into the BFKL equation splits the QCD pomeron into a series of isolated poles in complex angular…
Production of eta mesons in nucleon-nucleon collisions
V. Baru, A. M. Gasparyan, J. Haidenbauer +3
A microscopic calculation of near-threshold eta-meson production in the reaction NN -> NNeta is presented. It is assumed that the eta meson is produced via direct emission and via…
Alternation of different fluctuation regimes in the stock market dynamics
J. Kwapien, S. Drozdz, J. Speth
Based on the tick-by-tick stock prices from the German and American stock markets, we study the statistical properties of the distribution of the individual stocks and the index re…
Application of an Extended Random Phase Approximation on Giant Resonances in Light, Medium and Heavy Mass Nuclei
V. Tselyaev, N. Lyutorovich, J. Speth +2
We present results of the time blocking approximation (TBA) on giant resonances in light, medium and heavy mass nuclei. The TBA is an extension of the widely used random-phase appr…
Role of the isobar in the reaction near threshold
C. Hanhart, J. Haidenbauer, O. Krehl +1
A model calculation for pion production in nucleon-nucleon collisions is presented. Direct production, pion rescattering and contributions from pair diagrams are taken into account…
An analysis of the reaction pp --> ppηnear threshold
K. Nakayama, J. Haidenbauer, C. Hanhart +1
It is shown that most of the available data on the reaction, including the invariant mass distributions in the reaction recently measured at COSY, can be…
Modeling Complex Nuclear Spectra - Regularity versus Chaos
S. Drozdz, S. Nishizaki, J. Speth +1
A statistical analysis of the spectrum of two particle - two hole doorway states in a finite nucleus is performed. On the unperturbed mean-field level sizable attractive correlatio…
Angular asymmetries in the reactions pp \to dÏ^+ηand pn \to dÏ^0ηand a_0-f_0 mixing
A. E. Kudryavtsev, V. E. Tarasov, J. Haidenbauer +2
The reactions pp\to dÏ^+ηand pn\to dÏ^0ηare of special interest for investigating the a_0(980) (J^P=0^+) resonance in the process NN \to da_0 \to dÏη. We study some aspects o…
How to measure the pion structure function at HERA
H. Holtmann, G. Levman, N. N. Nikolaev +2
We suggest a method of determination of the pion structure function down to x \simeq 10^{-4} based on semi-exclusive deep inelastic scattering off protons. The idea is to exploit t…
The Reaction and the Validity of the OZI Rule
J. Haidenbauer, K. Nakayama, J. W. Durso +2
The reaction is investigated within a relativistic meson-exchange model of hadronic interactions. The possibility of extracting the coupling constant from a s…
Meson-meson scattering: -thresholds and mixing
O. Krehl, R. Rapp, J. Speth
We study the influence of mass splitting between the charged and neutral pions and kaons in the Juelich meson exchange model for and scattering. The calculations are…
Eta Meson Production in NN Collisions
K. Nakayama, J. Speth, T. -S. H. Lee
Eta meson production in both proton-proton and proton-neutron collisions is investigated within a relativistic meson exchange model of hadronic interactions. It is found that the a…
Absorptive corrections to the one pion exchange and measurablity of the small-x pion structure function at HERA
N. N. Nikolaev, J. Speth, B. G. Zakharov +1
We compaWe compare the absorptive corrections to the one pion exchange in and reactions. It is shown that the absorption is stronger in the case of col…
The reactions and near their thresholds
A. Gasparian, J. Haidenbauer, C. Hanhart +2
The reactions and are studied near their thresholds. The strangeness production process is described by the - and exchange mechanisms. Effec…
Correlation Effects in the Final-State Interaction for Quasielastic Scattering
N. N. Nikolaev, A. Szczurek, J. Speth +3
Color transparency predicts that, in reactions at large , the final-state interaction becomes weaker than the reference value predicted from the free-nucleon cross s…
Phenomenological analysis of K+ meson production in proton-nucleus collisions
M. Buescher, B. L. Ioffe, V. Koptev +5
Total and differential cross sections from literature, on the production of K+ mesons in pA interactions at projectile energies between T=0.8 and 2.9 GeV, covering the transition a…
The piNN vertex function in a meson-theoretical model
R. Boeckmann, C. Hanhart, O. Krehl +2
The piNN vertex function is calculated within a dispersion theoretical approach, including both pi-rho and pi-sigma intermediate states, where the sigma meson is an abbreviation fo…
Are the contemporary financial fluctuations sooner converging to normal?
S. Drozdz, J. Kwapien, F. Gruemmer +2
Based on the tick-by-tick price changes of the companies from the U.S. and from the German stock markets over the period 1998-99 we reanalyse several characteristics established by…
Self-consistent calculations of the electric giant dipole resonances in light and heavy mass nuclei
N. Lyutorovich, V. Tselyaev, J. Speth +3
While bulk properties of stable nuclei are successfully reproduced by mean-field theories employing effective interactions, the dependence of the centroid energy of the electric gi…