Spectrometry of nebulae

Observatoire de Strasbourg, 11 rue de l’Université, 67000 Strasbourg, France

e-mail: agnes.acker@astro.unistra.fr

Abstract

Nebular emission lines are easy to observe, and their spectrum contains a lot of information. We explain the mechanisms of production of the emissions, and the relation between the intensity of the recombination and forbidden lines, and the physical parameters of the objects. A gallery of emission lines spectra is presented, and a rough analysis will clarify their differences. The case of Planetary Nebulae will be developed, in order to determine the extinction constant, the plasma parameters (electron density and temperature), the chemical abundances, and also the properties of the central star (temperature, mass, stellar wind velocity, age).