ar X iv : a st ro - p h / 03 02 58 7 v 1 2 8 Fe b 20 03 Semi – linear gravitational lens inversion

ar X iv : a st ro - p h / 03 02 17 7 v 1 1 0 Fe b 20 03 Polarization in GRB Afterglows

ar X iv : a st ro - p h / 03 02 42 4 v 1 2 0 Fe b 20 03 Stochastic appearance in stars and high energy sources

Many phenomena such as stellar variability, stellar explosions, behavior of different kind of X-ray and gamma-ray sources, processes in active galactic nuclei and other astrophysical objects show stochastic features. Brief description of these phenomena is given in this review.

ar X iv : a st ro - p h / 03 02 48 0 v 1 2 4 Fe b 20 03 23 Field and cluster RR Lyrae stars as stellar tracers

We present an overview on pulsation properties of RR Lyrae stars in the Galaxy and in Local Group dwarf galaxies. We discuss the key information that RR Lyrae might provide on their parent population, and in particular on their metallicity distribution.

ar X iv : m at h / 03 02 33 9 v 1 [ m at h . A P ] 2 7 Fe b 20 03 NONLINEAR SCHRÖDINGER EQUATIONS WITH STARK POTENTIAL

We study the nonlinear Schrödinger equations with a linear potential. A change of variables makes it possible to deduce results concerning finite time blow up and scattering theory from the case with no potential.

ar X iv : a st ro - p h / 03 02 30 7 v 1 1 6 Fe b 20 03 The Local Interstellar Spectrum of Cosmic Ray Electrons . Direct measurements

The local interstellar spectrum of cosmic ray electrons is derived by correcting the data from balloon and space measurements for the solar modulation effect. The resulting spectrum, after the renormalization of some experimental data set, can be fitted with a single power law from about 3 GeV to 2 TeV with spectral index γ = 3.42± 0.02. On the other hand, at low energies the measurements by CA...