Echo-tomgraphy is an indirect imaging technique which uses multiwavelength observations of LMXBs to constrain the fundamental parameters of these binaries. In particular, it uses time delays between X-ray and UV/optical light-curves as a function of orbital phase in order to map the reprocessing sites in a binary. Since previous works probe that

We have used multi-band high resolution HST WFPC2 and ACS observations combined with wide field ground-based observations to study the blue straggler star (BSS) population in the galactic globular cluster NGC 6388. As in several other clusters we have studied, the BSS distribution is found to be bimodal: highly peaked in the cluster center, rapidly

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Extensive spectroscopic studies of stars with and without planetary systems have concluded that planet host stars are more metal-rich than those without detectable planets. More subtle trends of different chemical elements begin to appear as the number of detected extrasolar planetary systems continues to grow. I review our current knowledge

We present the [X/H] trends as a function of the elemental condensation temperature Tc in 88 planet-host stars and in a volume-limited comparison sample of 33 dwarfs without detected planetary companions. We gathered homogeneous abundance results for many volatile and refractory elements spanning a wide range of Tc, from a few dozen to several