PKS 0537-441, a bright gamma -ray emitting blazar, was observed at radio, optical, UV and X-ray frequencies during various EGRET pointings, often quasi-simultaneously. In 1995 the object was found in an intense emission state at all wavelengths. BeppoSAX observations made in 1998, non-simultaneously with exposures at other frequencies, allow us to

Brown dwarfs are objects unable to sustain hydrogen burning in their interiors. Deep surveys and large scale infrared surveys have identified a few hundred candidates free-floating in star clusters and in the solar neighborhood. Several brown dwarf companions to low-mass stars have also been detected. In the absence of a direct mass determination

We present Keck Observatory 10 m telescope spectra of the two Pleiades brown dwarfs, Teide 1 and Calar 3, showing a clear detection of the Li 670.8 nm resonance line. In Teide 1, we have also obtained evidence for the presence of the subordinate line at 812.6 nm. A high Li abundance [log N(Li) >= 2.5], consistent with little if any depletion, is

Context: Analysis of bulges to redshifts of up to z ˜ 1 have provided ambiguous results as to whether bulges as a class are old structures akin to elliptical galaxies or younger products of the evolution of their host disks. Aims: We aim to define a sample of intermediate-z disk galaxies harbouring central bulges, and a complementary sample of disk

In an ongoing effort to study the formation and evolution of galactic bulges, we have investigated the position of 19 bulges of type S0-Sbc on the Fundamental Plane (FP). We find that bulges, in both B and K band, lie close to but slightly below the FP defined by ellipticals and S0s, i.e. are slightly brighter. There are hints that bulges of later

In the Minimal Supersymmetric Standard Model (MSSM) the existence of an upper bound on the mass of the $CP=+1$ lightest Higgs boson, equal to $m_Z$ at tree--level and $simlt 120 GeV$ after the inclusion of radiative corrections, has important phenomenological consequences for Higgs searches. A similar bound, independent of mass parameters other