>From memory, correlation length is the length during which the phase of the electric field is preserved. It's typically computed by applying time (pulse width)- frequency (converted to length) uncertainty principle.
V. Nagarajan JAN Scientific, Inc. -----Original Message----- From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of Bernhard Rupp Sent: Thursday, January 29, 2009 9:51 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] X-ray photon correlation length I always wondered - how is the X-ray photon correlation length defined and where do I find it? This is not the interaction length, I assume. So, to the physicists: How large is the 'X-ray photon correlation length' for a given wavelength in a given material? I had the impression that the term photon correlation refers to the time correlation of the scattering such as in photon correlation spectroscopy. Best regards, BR