Related papers: Naive parton picture for kaon color transparency i…
The study of color transparency (CT) in elastic electroproduction of vector mesons off nuclei encounters the problem of the onset of coherence length (CL) effects. The problem of CT-CL separation arises especially at medium energies,…
Relativistic and unfactorized calculations for the nuclear transparency extracted from exclusive A(e,e'p) reactions for 0.3 \leq Q^2 \leq 10 (GeV/c)^2 are presented for the target nuclei C, Si, Fe and Pb. For Q^2 \geq 0.6 (GeV/c)^2, the…
We provide a perspective on studies aimed at observing the transition between hadronic and quark-gluonic descriptions of reactions involving light nuclei. We begin by summarizing the results for relatively simple reactions such as the pion…
The use of nuclear transparency effect of \pi^{-}-mesons in proton, and deuteron induced interactions with carbon nuclei at 4.2A GeV/c, to get information about the properties of nuclear matter, is presented in this work. Half angle…
High-resolution in-beam $\gamma$-ray spectroscopy was used to study excited states of the neutron-deficient nucleus $^{32}$Ar populated in fast-beam induced four- and six-nucleon removal reactions from $^{36,38}$Ca. One new $\gamma$-ray…
New preliminary results on kaon and pion production in central 30AGeV Pb+Pb collisions are presented. The data are compared to data at lower and higher energies to examine the energy dependence of the kaon to pion ratios and the inverse…
We re-examine the predictions of a two-phase model of shadowing in nuclear deep-inelastic scattering in light of new NMC data on the x, A and Q**2 dependence of the ratios of structure functions. The model, which combines vector meson…
The formation and excitation of hypernuclei through kaon photoproduction is reviewed. Basic features of the production process are emphasized. The possibility of extracting new information on hypernuclear structure and on the wave function…
We derive the non-abelian generalization of the Furry approximation which describes the transverse dynamical evolution of a hard projectile parton inside a spatially extended colour target field. This provides a unified starting point for…
The transparency of the hadrons produced in the $\gamma (n,p) \pi^-$ reaction in nuclei is calculated using the Glauber model modified by including the Fermi motion of the nucleon in the nucleus. Since the calculated results underestimates…
Spectra of positively charged kaons in p+C interactions at 31 GeV/c were measured with the NA61/SHINE spectrometer at the CERN SPS. The analysis is based on the full set of data collected in 2007 with a graphite target with a thickness of…
We evaluate the shadowing effect in deeply virtual and real Compton scattering on nuclei in the framework of the color dipole model. We rely on the soft photon wave function derived in the instanton vacuum model, and employ the impact…
Color Transparency refers to the vanishing of the hadron-nucleon interaction for hadrons produced inside a nucleus in high momentum exclusive processes. We briefly review the concept behind this unique Quantum Chromo Dynamics' phenomenon,…
Rare leptonic kaon and pion decays $K^+(\pi^+) \to \mu^+\, \nu_{\mu}\, e^+ e^-$ can be used to probe a dark photon of mass ${\cal O}(10)$~MeV, with the background coming from the mediation of a virtual photon. This is most relevant for the…
Color transparency CT depends on the formation of a wavepacket of small spatial extent. It is useful to interpret experimental searches for CT with a multiple scattering scattering series based on wavepacket-nucleon scattering instead of…
The dependence of K+ production on the nuclear equation of state is investigated in heavy ion collisions. An increase of the excitation function of K+ multiplicities obtained in heavy (Au+Au) over light (C+C) systems when going far below…
We study the kaon nuclear optical potential including the effect of the \Theta^+ pentaquark in a self-consistent approach, starting from an extension of the Juelich meson-exchange potential as bare kaon-nucleon interaction. Significant…
We investigate the $\phi$ meson nuclear transparency using some recent theoretical developments on the $\phi$ in medium self-energy. The inclusion of direct resonant $\phi N$-scattering and the kaon decay mechanisms leads to a $\phi$ width…
The kaon number density in nucleus+nucleus and p+p reactions is investigated for the first time as a function of the initial energy density $\epsilon$ and is found to exhibit a discontinuity around $\epsilon$=1.3 GeV/fm$^3$. This suggests a…
We present our results for the exclusive electroproduction of pions off nucleons and nuclei at high values of $Q^2$. In electroproduction of nuclei $A(e,e'\pi)$ we consider the Color Transparency (CT) effect recently observed at JLAB. It is…