Difference between revisions of "A kind of analysis"

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We should define how many peaks to use.
 
We should define how many peaks to use.
  
If the calculation of <math>\frac{N_\gamma}{N_n}</math> I will use just integration of area under the curve (I got 0.36% difference between areas calculated in these two ways).
+
If the calculation of <math>\frac{N_\gamma}{N_n}</math> I will use just integration of area under the curve (I got about 0.36% difference between areas calculated in these two ways).

Revision as of 01:48, 2 January 2009

[math]\gamma[/math]-peak positions are shifted w.r.t. each other due to the difference in TOF conversion (electronics amplification). If we wanna calculate the asymmetry as a function of TOF for each channel (neutron energy) it is necessary to match the positions of centroids of [math]\gamma[/math]-peaks. However, one needs to take into account the difference between channel-to-TOF calibration coefficients for each detector.

This is what we have if we superimpose TOF-spectra within one plot. It was used used the average channel-to-TOF calibration coefficient (0.179+0.186+0.19)/3 = 0.185 ns/channel (Is it okay to do that?).

Asym 0.jpg


Asym 11.jpg

Channel-to-TOF calibration coefficients used was 0.19 ns/channel. [math]\gamma[/math]-peak positions were matched manually by cutting out the shift in the spectra w.r.t. Ref Det.


The following plot was drawn using upper plot and formula for calculation of asymmetry placed at [[1]]


Asym 2.jpg


Separation of TOF.jpg


Separation of TOF2.jpg

We should define how many peaks to use.

If the calculation of [math]\frac{N_\gamma}{N_n}[/math] I will use just integration of area under the curve (I got about 0.36% difference between areas calculated in these two ways).