Open AccessOptimizing the signal‐to‐noise ratio for X‐ray photon correlation spectroscopy
Author(s) -
Falus P.,
Lurio L. B.,
Mochrie S. G. J.
Publication year - 2006
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049506006789
Subject(s) - detector , physics , optics , pixel , collimated light , coherence (philosophical gambling strategy) , signal to noise ratio (imaging) , photon , energy (signal processing) , spectroscopy , signal (programming language) , coherence length , computer science , laser , superconductivity , quantum mechanics , programming language
An analysis is presented of how to optimize the experimental beamline configuration for achieving the best possible signal‐to‐noise ratio (SNR) in X‐ray photon correlation spectroscopy experiments using area detectors. It is shown that there exists an optimum detector distance; namely, the highest SNR is achieved by matching the angular pixel size with the angular source size. Binning several pixels together can increase the SNR by permitting to match the shape of a detector pixel to the shape of the source. It is also shown that collimating slits several times wider than the effective transverse coherence length are optimal; further, it is demonstrated that the energy dependence of the SNR is dictated by the energy dependence of detector efficiency and source brilliance. Ultimately the effects of focusing and low longitudinal coherence are discussed.