Difference between revisions of "BCAL Beam Test Plots, November 20, 2006"
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;Can anyone explain why Ephoton vs tphoton has this pattern? Is it uncertainty in the timing offsets for the tagger t-counters? Is this fixable or something we have to live with? The tphoton scale is blown up but it's still curious. | ;Can anyone explain why Ephoton vs tphoton has this pattern? Is it uncertainty in the timing offsets for the tagger t-counters? Is this fixable or something we have to live with? The tphoton scale is blown up but it's still curious. | ||
[[Image:Ephoton vs tphoton.gif|left|480px]] | [[Image:Ephoton vs tphoton.gif|left|480px]] | ||
− | [[Image:AdcsumN vs tphoton.gif| | + | [[Image:AdcsumN vs tphoton.gif|none|480px]] |
+ | <br> | ||
+ | And if you cut on 500<Ephoton<550 you get | ||
+ | [[Image:Tphoton adcsumN 500to550.gif|480px]] |
Revision as of 18:36, 23 November 2006
First go
- Gain Correction:
- Establish the means of each cell in the Monte Carlo and find the ratio wrt MC Cell 8 over whole tagger spectra
- Find the current ratio of each ADC in the beamtest data wrt to North 8
- Correct the ADC ratio to match the Monte Carlo Ratios
- The ratio of MC Cell 8 to North 8 defines the MeV/Channel
- How does this look over the entire tagger spectrum?
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?
- Very Strange: Apparent Energy Dependence
- How do we see what's going on?
- 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
- Cut out the lower hump from the ADC sum.
- 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?
- -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
It was suggested I start looking at tdc information for making cuts.
- The veto almost has no information for run 2334
- Can anyone explain why Ephoton vs tphoton has this pattern? Is it uncertainty in the timing offsets for the tagger t-counters? Is this fixable or something we have to live with? The tphoton scale is blown up but it's still curious.