The observed antlcorrelation between diffuse soft X-ray flux and H I column density has been explained as absorption of soft X-rays produced in a hot galactic halo, assuming that the neutral interstellar material is sufficiently clumped to reduce the soft X-ray absorption cross section by a factor of two to three. We have extended a 21 cm emission line study of H I column density variations at ...

A detailed knowledge of the formation of carbon-bearing molecules in interstellar ices and in the gas phase of the interstellar medium is of paramount interest to understand the astrochemical evolution of cold molecular clouds, circumstellar envelopes, and of star-forming regions. Since the present composition of each interstellar environment reflects the matter from which it was formed and the...

Relic neutralinos produced after the Big Bang are favoured candidates for Dark Matter. They can accumulate at the centre of massive celestial objects like our Sun. Their annihilation can result in a high-energy neutrino flux that could be detectable as a localised emission with earthbased neutrino telescopes like ANTARES. In this paper a brief overview of the prospects of the indirect search fo...

This contribution addresses the different approaches that are developed in our laboratory to study the chemical evolution of organic matter in stellar or interplanetary environments. In the first approach, starting from interstellar or cometary ice analogs subjected to different energy processes (thermal, photochemical), we aim to explain the mechanism of formation of key molecules (RING projec...

We discuss the connection between the chemistry of dense interstellar clouds and those characteristics of cometary matter that could be remnants of it. The chemical evolution observed to occur in molecular clouds is summarized and a model for dense core collapse that can plausibly account for the isotopic fractionation of hydrogen, nitrogen, oxygen and carbon measured in primitive solar system ...

Introduction: Organic matter in primitive meteorites may have mostly been formed in the interstellar medium [e.g. 1-3]. After formation of the solar system these molecules have been incorporated into the parent bodies of the various primitive meteorites [2]. Subsequent aqueous alteration and thermal metamorphism have altered the initially similar set of compounds including their carbonaceous mi...

This paper presents a possible way to understand dissolution of OB associations (or groups). Assuming rapid escape of parental cloud gas from associations, we show that the shadow of the formation environment for associations can be partially imprinted on the velocity dispersion at their dissolution. This conclusion is not surprising as long as associations are formed in a multiphase interstell...

Organic materials isolated from carbonaceous meteorites provide us with a record of pre-biotic chemistry in the early Solar System. Molecular, isotopic and in situ studies of these materials suggest that a number of extraterrestrial environments have contributed to the inventory of organic matter in the early Solar System including interstellar space, the Solar nebula and meteorite parent bodie...