Raga A.C., Cantó J. et al. The physics of the interstellar medium

ICN-UNAM, 2020 — 261p. The book "The physics of the interstellar medium" (auth. A.C. Raga, J. Cantó, A., & Rodríguez-González) reflects the content of and is based on notes for the ISM course which has been given at the UNAM by Jorge Canto and Alejandro Raga for over 25 years. In the more recent years, the lectures of this course are being taken over by members of the “new generation” of our group: Alejandro Esquivel, Ary Rodrıguez Gonzalez and Pablo Velazquez. The course (as well as the book) is divided into four main parts: I. a general introduction (in which this chapter is included), II. the physical processes in the ionised ISM and models of static photoionised regions. This part of the course is in the style of the classical books of Aller and Osterbrock (the latter in its multiple editions) and includes discussions of the basic processes, the ionisation and excitation state of the gas, and the prediction of the observed line and continuum spectrum, III. the dynamics of the ISM. This part starts with a derivation of the gas dynamic equations and simple, general solutions of astrophysical interest (sound waves, instabilities and shock waves). This is followed by a selection of problems of ISM dynamics (e.g., expansion of HII regions, SN remnants and winds), IV. astrophysical jets.