Alberto A. Vittone – författare

In the last few years great improvements in the study of stellar jets and bipolar outflows have been achieved, both observationally and theoretically. High resolution observations at various frequencies (radio, IR, optical and X-ray) of these features in different types of objects have shown a large variety of morphologies at all scales often revealing contrasting symmetries which do not allow straightforward kinematic interpretations valid for all cases. In particular, at present, it seems very difficult to give a statistical definition of what the "standard properties" of jets and bipolar outflows are. On the theoretical side, the identification of physical processes capable of producing the observed rich morphological variety of jets and bipolar outflows and supporting them over long lifetimes is still controversial. Furthermore several models are actively discussed in an attempt of reaching a complete understanding of the phenomenon. The workshop provided an unique opportunity for both observers and theoreticians to gather together and produce an updated and exhaustive picture of the field. In addition the meeting has been enriched by the presentation of some works on jets in external galaxies. This topic was focused on what people working on stellar jets could learn from colleagues working on extragalactic jets and vice versa. Invited papers were prepared with the aim of giving the state of the art about scientific subjects; contributed papers and some selected poster papers presented, on the contrary, very recent results in the various fields.

Solid matter in space is crucial in accounting for many processes. In these last years a great improvement of the general knowledge of the problem has been possible due to the increase, in number and quality, of observations and of the laboratory efforts to simulate "cosmic" dust. Theoreticians have also given their contribution in solving some questions and in posing others. Continuing an effort started in 1987, the Astrophysical Groups operating in Naples th th have considered it useful to organize a Workshop in Capri from September 8 to 13 1989 in order to assess the state of the art in such an interesting field as that of "Dusty Objects in the Universe". The subject is, obviously, too wide to be discussed in detail. However, the presence of many experts in different areas provided an updated general picture. Laboratory work has been reviewed, as well as recent observations and theoretical interpretations which concern processes occurring in our Galaxy and in external galaxies. The Workshop gave to participants the unique opportunity of exchanging ideas and of discussing on different themes. In addition, the meeting has been enriched by the presentation of the major technological projects related to ongoing airborne and space mlSSlons. the aim of giving the state of the art about specific Invited papers were prepared with subjects; contributed papers and some selected poster papers presented, on the contrary, the various fields.

The same kind of physics is frequently common to very different fields of Astrophysics, so experts in each of these fields have often much to learn from each others. It was therefore logical that the International Astronomical Union should sponsor a colloquium about an ion which pro­ duces many spectral lines that can be used as a diagnostic for many sorts of objects, and which may sometimes have a major influence on physical processes occurring in astro­ physical sources. The lines of singly ionized iron (FeII) are present in absorption and emission in the spectra of objects such as the Sun, cool stars, circumstellar envelopes of hot stars, novae, diffuse nebulae including the supernova remnants, and active galactic nuclei. These lines are very often formed far from LTE, and their interpretation is not easy in view of the complex Grotrian diagram for FeII, and the gaps in the knowledge of various physical parameters. In addition, the density of very strong FeII lines becomes very large in the ultraviolet, and the lines can play a major role in the line blanketing. They need therefore to be taken into account in any energy balance argument.

In the last few years great improvements in the study of stellar jets and bipolar outflows have been achieved, both observationally and theoretically. High resolution observations at various frequencies (radio, IR, optical and X-ray) of these features in different types of objects have shown a large variety of morphologies at all scales often revealing contrasting symmetries which do not allow straightforward kinematic interpretations valid for all cases. In particular, at present, it seems very difficult to give a statistical definition of what the "standard properties" of jets and bipolar outflows are. On the theoretical side, the identification of physical processes capable of producing the observed rich morphological variety of jets and bipolar outflows and supporting them over long lifetimes is still controversial. Furthermore several models are actively discussed in an attempt of reaching a complete understanding of the phenomenon. The workshop provided an unique opportunity for both observers and theoreticians to gather together and produce an updated and exhaustive picture of the field. In addition the meeting has been enriched by the presentation of some works on jets in external galaxies. This topic was focused on what people working on stellar jets could learn from colleagues working on extragalactic jets and vice versa. Invited papers were prepared with the aim of giving the state of the art about scientific subjects; contributed papers and some selected poster papers presented, on the contrary, very recent results in the various fields.

Solid matter in space is crucial in accounting for many processes. In these last years a great improvement of the general knowledge of the problem has been possible due to the increase, in number and quality, of observations and of the laboratory efforts to simulate "cosmic" dust. Theoreticians have also given their contribution in solving some questions and in posing others. Continuing an effort started in 1987, the Astrophysical Groups operating in Naples th th have considered it useful to organize a Workshop in Capri from September 8 to 13 1989 in order to assess the state of the art in such an interesting field as that of "Dusty Objects in the Universe". The subject is, obviously, too wide to be discussed in detail. However, the presence of many experts in different areas provided an updated general picture. Laboratory work has been reviewed, as well as recent observations and theoretical interpretations which concern processes occurring in our Galaxy and in external galaxies. The Workshop gave to participants the unique opportunity of exchanging ideas and of discussing on different themes. In addition, the meeting has been enriched by the presentation of the major technological projects related to ongoing airborne and space mlSSlons. the aim of giving the state of the art about specific Invited papers were prepared with subjects; contributed papers and some selected poster papers presented, on the contrary, the various fields.

The same kind of physics is frequently common to very different fields of Astrophysics, so experts in each of these fields have often much to learn from each others. It was therefore logical that the International Astronomical Union should sponsor a colloquium about an ion which pro­ duces many spectral lines that can be used as a diagnostic for many sorts of objects, and which may sometimes have a major influence on physical processes occurring in astro­ physical sources. The lines of singly ionized iron (FeII) are present in absorption and emission in the spectra of objects such as the Sun, cool stars, circumstellar envelopes of hot stars, novae, diffuse nebulae including the supernova remnants, and active galactic nuclei. These lines are very often formed far from LTE, and their interpretation is not easy in view of the complex Grotrian diagram for FeII, and the gaps in the knowledge of various physical parameters. In addition, the density of very strong FeII lines becomes very large in the ultraviolet, and the lines can play a major role in the line blanketing. They need therefore to be taken into account in any energy balance argument.