We report CGRO, RXTE, ASCA, ROSAT, IUE, HST and ground-based observations of a large flare in 3C 279 in February 1996. X-rays and γ-rays peaked simultaneously (within one day). We show simultaneous spectral energy distributions prior to and near the flare peak. The γ-ray flare was the brightest ever observed in this source.

Since its discovery in 1992, the superluminal X-ray transient GRS 1915+105 has been extensively observed in an attempt to understand its behaviour. We present here preliminary results from a multi-wavelength campaign undertaken from July to September 1996. This study includes X-ray data from the RXTE All Sky Monitor and BATSE, two-frequency data

In this Letter, we show that the optically bright stars above the tip of the first red giant branch (TRGB) in the color-magnitude diagrams (CMDs) of nearby dwarf elliptical (dE) galaxies, commonly interpreted as indication of the existence of an intermediate-age population, may be, in certain circumstances, an artifact of observational effects on a

Gravitational lenses are a consequence of the bending of light rays, which is one of the "classical" tests of Einsteins' General Relativity. This phenomenon appears when a large amount of mass, one or several galaxies, is located near the line-of-sight connecting the observer with a remote bright source, a quasar, far-off from both objects. In this

We included 2 tables containing photometric data, together equivalent width of LiI6708 A, for a sample of dwarf components of Chromospherically Active Binaries (CABs). (3 data files).

Background information is presented on the T Tauri stars observed with the IUE until the end of 1994. The log of observations and the UV spectrum are provided for all the objects as well as the FES light curves until November 1992. This information is completed with basic data on the individual sources.