Ebook: The Interstellar Medium in Galaxies

It has been more than five decades ago that Henk van de Hulst predicted the observability of the 21-cm line of neutral hydrogen (HI ). Since then use of the 21-cm line has greatly improved our knowledge in many fields and has been used for galactic structure studies, studies of the interstellar medium (ISM) in the Milky Way and other galaxies, studies of the mass distribution of the Milky Way and other galaxies, studies of spiral struc­ ture, studies of high velocity gas in the Milky Way and other galaxies, for measuring distances using the Tully-Fisher relation etc. Regarding studies of the ISM, there have been a number of instrumen­ tal developments over the past decade: large CCD's became available on optical telescopes, radio synthesis offered sensitive imaging capabilities, not only in the classical 21-cm HI line but also in the mm-transitions of CO and other molecules, and X-ray imaging capabilities became available to measure the hot component of the ISM. These developments meant that Milky Way was no longer the exclusive playground for ISM studies and that by reaching out to other galaxies astronomy had gained the advantage of having an "outside" view, though at the expense of giving up some linear resolution. Studies of the ISM in other galaxies are intimately connected to studies of the ISM in the Milky Way.

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The Interstellar Medium in Galaxies is a collection of seven reviews covering the following constituents of the interstellar medium: dust, molecular gas, neutral atomic hydrogen, ionized hydrogen, and hot gas, and covering the abundances of heavy elements in the interstellar medium and the role of star formation. The reviews not only provide a good background in these subjects, but also describe in detail the most recent advances in the area and discuss the current problems in the field. The properties of the different constituents of the interstellar medium are discussed within the perspective of the difference in properties of the parent galaxies and the environment. The interplay between star formation and the characteristics of the interstellar medium is also discussed in detail.
This volume provides very up-to-date material on the subject of the interstellar medium in galaxies and is useful both as a basic reference for professional scientists in this field and as an introductory book for astronomers who want to familiarize themselves with this field. This volume can also serve as an accompanying text book for graduate courses on the interstellar medium.