Hydrogen Line Profiles

Modelling of Nebular Line Profiles

RESUMEN El resumen será traducido al español por los editores. We present a tool, VELNEB 3D, which can be applied to the results of 3D photoionization codes to generate emission line profiles, position-velocity maps and 3D maps in any emission line by assuming an arbitrary velocity field. We give a few examples, based on our pseudo-3D photoionization code NEBU 3D (Morisset, Stasi´nska & Peña 20...

Molecular Line Profiles of Collapsing Gas Clouds

Emission line profiles of tracer molecule H2CO 140 GHz transition from gravitational core collapsing clouds in the dynamic process of forming protostars are calculated, using a simple ray-tracing radiative transfer model. Three self-similar dynamic insideout core collapse models – the conventional polytropic model, the empirical hybrid model and the isothermal model – for star-forming molecular...

Astrophysical water masers : Line profiles analysis

The changes in the spectral line profile of the 22 GHz H 2 O maser are calculated as a function of emerging maser flux. We address not only the narrowing and re-broadening of the maser lines, but also the deviations of Gaussian symmetry as a result of the various hyperfine components of the 22 GHz maser line. Non-LTE models of the H 2 O maser transition, including hyperfine structure and cross-...

Alkali Line Profiles in Degenerate Dwarfs

Ultracool stellar atmospheres show absorption by alkali resonance lines severely broadened by collisions with neutral perturbers. In the coolest and densest atmospheres, such as those of T dwarfs, Na I and K I broadened by molecular hydrogen and helium can come to dominate the entire optical spectrum. Their profiles have been successfully modelled with accurate interaction potentials in the adi...

Research Investigation of Laser Line Profiles