Pressure Broadening of Spectral Lines

This is a book about pressure broadening the shape of spectral lines. It is primarily aimed at atmospheric physicists concerned with gas phase radiative transfer, but reaches out, more generally, to anyone who is interested in line broadening by neutralperturbers. The only conditions I have imposed are that the pressure of the gas must be sufficiently low, as in the atmosphere, to ensure that collisions may be regarded as binary in nature, yet sufficiently high to establish local thermodynamic equilibrium, which will be true of the atmosphere except at very high altitudes. To the extent that these conditions are still met, the book will be useful to astrophysicists concerned with broadening of this kind within the atmospheres of other planets, stars even, and I give some pointers at the very end to show in what way the theories discussed here may be used when the gas is ionized. It may also appeal to students of quantum mechanics or spectroscopy more generally. This is because it proceeds from acorn tooak tree in an explanatory and accessible manner, and will show how quantum interactions that are hidden at the molecular level lead to ows of energy that may be observed at any time at the level of common experience--