Hi Bernhard,
On Wed, Oct 13, 2010 at 08:07:04PM -0700, Bernhard Rupp wrote:
[...]
> BR
>
> PS: Just in case it might come up - there is NO destructive interference
> between F000 and direct beam - the required coherence that leads to
> extinction/summation of 'partial waves' is limited to a single photon.
> Standard (non-FEL) X-ray sources are (with minor exceptions in special
> situations) not coherent. Has been discussed many times on bb.
This sounds as though you are saying that a single photon interacts with several
electrons to give rise to a reflection. If I understand Feynman diagrams
correctly, this does not conform with current notion of photons. If your
statement refers to a chapter in your book, please point that out before we
discuss this on the bb so that I can set myself right.
Cheers, Tim
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Tim Gruene
Institut fuer anorganische Chemie
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D-37077 Goettingen
phone: +49 (0)551 39 22149
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