General concepts of laser spectroscopy

Photon detection methods are associated with absorption, emission or scattering of electromagnetic radiation by atoms and molecules (or atomic and molecular ions). 

Ion detection methods rely on the phenomenon that the interaction of photons with a neutral particle results in its ionization either the negatively charged electron or the positively charged atomic/molecular ion can be detected. 

A range of detection procedures exploit that the absorption of radiative energy changes the physical properties of the absorbing medium it is the change in the property of the medium that is measured to deduce the interaction process. 

Most of the detection methods summarized here, and described in more detail in the following sections. 

Laser Chemistry Spectroscopy, Dynamics and Applications Helmut H. Telle, Angel Gonzalez Urena Robert J. Donovan 2007 John WUey Sons, Ltd ISBN 978-0-471-48570-4 (HB) ISBN 978-0-471-48571-1 (PB) 

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