Difference between revisions of "BCAL Beam Test Plots, November 20, 2006"

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*Compare North 8 over all spectra when cutting on adcsumN > Ch1000 ~ 140MeV to previous
 
*Compare North 8 over all spectra when cutting on adcsumN > Ch1000 ~ 140MeV to previous
 
[[Image:EnergyN8 adcsumcut.gif|320px|left|with cut]] [[Image:EnergyN8.gif|320px|none|previously]]
 
[[Image:EnergyN8 adcsumcut.gif|320px|left|with cut]] [[Image:EnergyN8.gif|320px|none|previously]]
−
[[Image:Energysum 2.gif|480px]]
+
: <math>  \frac{MC 8}{North 8} = 0.0167 \frac{MeV}{Channel}</math>
 +
[[Image:Energysum 2.gif|none|480px]]
 +
<br>
 
Looks reasonably closer except for the excess at the front of the spectra. I expect this is the contribution of the electrons or whatnot, the "junk", that we need to cut out.
 
Looks reasonably closer except for the excess at the front of the spectra. I expect this is the contribution of the electrons or whatnot, the "junk", that we need to cut out.

Revision as of 19:26, 19 November 2006

First go

  • Gain Correction:
    1. Establish the means of each cell in the Monte Carlo and find the ratio wrt MC Cell 8 over whole tagger spectra
    2. Find the current ratio of each ADC in the beamtest data wrt to North 8
    3. Correct the ADC ratio to match the Monte Carlo Ratios
      • The ratio of MC Cell 8 to North 8 defines the MeV/Channel
North 7
North 8
North 9
North 12
{\frac {MC8}{North8}}=0.018{\frac {MeV}{Channel}}



How does this look over the entire tagger spectrum?
Energysum 1.gif

The 0.151 MeV/Ch is for a tagger photon (digregard this). The others are for energy deposit in the scintillator.

What if we look at MC 8 vs North 8 with Tagger Energy cuts?
North8 300<Ephoton<400
MC8 300<Ephoton<400
({\frac {MC8}{North8}})_{{300<Ephoton<400}}=0.0177{\frac {MeV}{Channel}}


North8 500<Ephoton<600
MC8 500<Ephoton<600
({\frac {MC8}{North8}})_{{500<Ephoton<600}}=0.0165{\frac {MeV}{Channel}}


  • Very Strange: Apparent Energy Dependence

Adccalib2.gif


How do we see what's going on?
  1. Cuts: Trig==8 (MOR and BCal OR), Nphotons==1
    • Possibly there are e+e-, maybe. Need to check the veto but it doesn't seem to be in the Root Trees
    1. Cut out the lower hump from the ADC sum.
ADCsum South 200<Ephoton<300
ADCsum South 300<Ephoton<400
ADCsum South 500<Ephoton<600


  • This seems to remove the "junk" from the left of the spectra, and will flatten out the MC8/North8 ratio. But what is the "junk?
North8 junk 300to400.gif
  • -This has a 2% or more effect on the mean for 300<Ephoton<400. Probably much larger effect for the lower energies.



  • Compare North 8 over all spectra when cutting on adcsumN > Ch1000 ~ 140MeV to previous
with cut
previously
{\frac {MC8}{North8}}=0.0167{\frac {MeV}{Channel}}
Energysum 2.gif


Looks reasonably closer except for the excess at the front of the spectra. I expect this is the contribution of the electrons or whatnot, the "junk", that we need to cut out.

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