Michael Glazer wrote the following on 19/02/2008 09:42:
Or else one could take the peak intensity divided by the square root of the
background: this at least would improve with measurement time.
For instance suppose we have a peak above background of 10000 counts and a
background of 1000 counts, this would give a signal to noise ratio of roughly
322. If we measure ten times longer, the peak intensity becomes 100000 and the
background becomes 10000, giving a signal to noise ratio of 1000, an
improvement!
So my question remains: what is the definition of signal to noise ratio that
is accepted for powder diffraction?
This at least coincides with data collection practice in single crystal
diffraction: there it is said that in order to improve the 'signal to
noise' ratio with a factor of two you have to count 4 times longer, or,
alternatively, double the generator power.
Arie
