TY - JOUR A1 - Vollmer, Michael T1 - Hot gases : transition from line spectra to thermal radiation T2 - In: American journal of physics 73 (2005), 215-223 N2 - The question of how the line spectrum of atoms is transformed into the continuous spectrum of thermal radiation of a gas by repeated absorption and emission of photons is addressed. We consider a simple model of a hydrogen-like gas in thermal equilibrium where only the Lyman-α transition is allowed and calculate the spectra for increasing thickness of the gas. The transition from line spectra for optically thin samples to the spectra of thermal radiation for optically thick samples is demonstrated. We estimate the emissivities for hot gases and study the line width of spectral lines due to self-absorption processes. Y1 - 2013 UR - https://opus4.kobv.de/opus4-fhbrb/frontdoor/index/index/docId/418 SP - 215 EP - 223 ER -