Transcript 2012-05-30 Extract the x-ray energy spectrum based response to applied filters

2012-05-30
Extract the x-ray energy spectrum based response to applied filters
Expanded program has 7 energy bins. First bin edge 0.500, increment 0.667, last bin edge 5.169 .
Have the ability to take the 6 μm carbon filter in or out in the program
The high energy behavior is described by synchrotron radiation.
We do not know the efficiency effects of the diode passivation layer, or the diode junction.
There may be a low energy efficiency loss.
Start with a flat efficiency above 0.500 keV.
The resultant binned input energy distribution is shown.
Pinhole images for “no_filter” and “carbon filter” are
shown below.
The relative transmitted power is 0.144,
when considering the diffraction at lowest energy
but the observed relative transmission is 0.52 .
The loss is greater at low energy.
The conclusion is that the input spectrum
has less low energy component than
described by the synchrotron radiation
distribution.
The predicted unfiltered image
is wider than observed.
2012-05-30
If the first 2 energy bins have an
applied transmission of 0.052 , (a co-incidence in the numbers)
the relative transmitted power is 0.52 ,
in agreement with
the observed relative transmission is 0.52 .
2012-05-30
Similarly, if the first 3 energy bins have an
applied transmission of 0.026 ,
the relative transmitted power is 0.52 ,
in agreement with
the observed relative transmission is 0.52 .
These can not be distinguished with the carbon alone.
2012-05-30
With the molybdenum filter, and the pinhole optic,
the observed relative transmitted power 0.049 ±20%,
With flat efficiency above 0.500 keV,
the relative transmitted power is 0.014 (too low) .
With 0.052 applied transmission in the first 2 bins
(as before)
the relative transmission is 0.080 (too high).
And ,with 0.026 applied transmission in the first 3 bins
(as before)
the relative transmission is 0.029 (again, to low).
With 0.030 applied transmission in the first 2 bins
and 0.23 applied transmission in the 3rd bin,
the relative transmission is 0.050 .
The carbon filter, with the above applied transmission
has relative transmission 0.53 , still in agreement.