Difference between revisions of "Tegan's HDGEANT and mcsmear questions"

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(Created page with "= New code = * Poisson statistics smearing still needs a value for the energy of one dark hit. * What should we use for an energy threshold to write out events? A 4 mV thres...")
 
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= New code =  
 
= New code =  
 
* Poisson statistics smearing still needs a value for the energy of one dark hit.
 
* Poisson statistics smearing still needs a value for the energy of one dark hit.
−
* What should we use for an energy threshold to write out events?  A 4 mV threshold was used before.  4 MeV?
+
**Elton: 0.31 MeV, deposited at the center of the module, per pixel fired.  For 10 degrees, 1.0 V OB, and attenuated to the end of the module, 0.11 MeV or so.  This is [current code value]/6.
 
* The change to the data structure will be just adding 'incident_id="int"' to 'bcalTruthHit.'
 
* The change to the data structure will be just adding 'incident_id="int"' to 'bcalTruthHit.'
−
** If we don't change the data structure, we'll change bcal_index in the code and get rid of the incident particle filling.
+
**Should we also add EUP/EDN, tUP/tDN to the data structure?
−
** I'd prefer changing the data structure, since we'll eventually want to implement incident particle dependent smearing (I assume), and it seems relatively easy to do it now.
+
**If we do not, we'll have to grab C_EFFECTIVE and ATTEN_LENGTH from the ccdb in mcsmear instead of doing it in hdgeant like usual.
−
* Time smearing: the time resolution in the code for the fADC is stated as 4 ns / sqrt(12).  This was used before because we were using 0.1 ns bins rather than 4 ns bins.
+
 
−
** Is this value what we'd want to use for smearing a single truth time?
+
*I've changed the data structure and tested the output of the new code.  With the old code, a hit would be up to 1 GeV or so, usually around 50 - 300 MeV.
 +
**With the new code, I'm seeing numbers like 0.1 - 5 MeV. I'm trying to figure out where in the code I might have messed up.
  
 
= Old code =
 
= Old code =
 
* We need to decide whether or not we want to keep this method available for people to choose to use.
 
* We need to decide whether or not we want to keep this method available for people to choose to use.
−
* If we do keep it:
 
−
** Need to find a value for the energy of one dark hit that causes waveforms to more closely resemble data and also that gives reasonable pedestal variation.
 
−
** By fixing an electronic noise smearing, then altering the dark hit energy, it looks like we want something like the current energy divided by 10 or so.
 
−
** It should be easy to set the dark hit energy based on what amplitude in mV we want the dark pulses to have, if we have any feeling for that (1 mV amplitude ~ 1 MeV energy deposition).
 

Revision as of 16:38, 6 May 2015

New code

  • Poisson statistics smearing still needs a value for the energy of one dark hit.
    • Elton: 0.31 MeV, deposited at the center of the module, per pixel fired. For 10 degrees, 1.0 V OB, and attenuated to the end of the module, 0.11 MeV or so. This is [current code value]/6.
  • The change to the data structure will be just adding 'incident_id="int"' to 'bcalTruthHit.'
    • Should we also add EUP/EDN, tUP/tDN to the data structure?
    • If we do not, we'll have to grab C_EFFECTIVE and ATTEN_LENGTH from the ccdb in mcsmear instead of doing it in hdgeant like usual.
  • I've changed the data structure and tested the output of the new code. With the old code, a hit would be up to 1 GeV or so, usually around 50 - 300 MeV.
    • With the new code, I'm seeing numbers like 0.1 - 5 MeV. I'm trying to figure out where in the code I might have messed up.

Old code

  • We need to decide whether or not we want to keep this method available for people to choose to use.
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