June 11, 2007 Calorimetry

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Dial-In Information


Attendess: George, Zisis, Blake, Simon, David,Elke, Elton, Richard, Alex, Mihalio, Beni

Alex: Bcal test data and numerical calculations.

     the numerical calculation depends on the critial energy Ec and the effective radiation length
     very heavily. The effective rad. length X0 will be recalculated at Regina. The critical energy 
     comes in two versions(parametrizations) and it is not completley clear which to choose.
     It becomes now important to have a good gain calibration of all PMTs. Alex is working on this
     and will together with the Regina group collect all the information of the Bcal test data, simulation
     and numcerical calculations. 
     The energy calibration and gain matching is the most important point now.
     Also the results from cosmic data and simulation needs to be consolidated. different values are
     in peoples minds and need to be verified.

Blake: Bcal simulation

     at energies above 100MeV the sampling fraction is completely flat accroding to the MC with a value
     of 0.1247 of the total deposited energy in the calorimeter. The resolution of the sampling fraction
     between 100 and 700 MeV is nicely described by the curve (0.0456 +/- 0.0009)/sqrt(E) + (0.0155+/-0.0016)
     At energies below 50MeV the sampling fraction deviates heavily from a constant. It drops by 0.8% absolute
     from 50 to 10 MeV. 
     George points out that at 50 MeV the maximum but that this effect reaches probably up to about 200MeV.
     While at small energies a poisson distribution is needed to fit the energy fractional deposition, at
     50 MeV a gaussion fit is adequate.

David: the timing of the tagger is an issue hence David introduced the Tcounter id into the data stream.

     George points out that the size of the molere radius has an influence on the timeing in the BCAL and
     is under investigation at Regina.

Mihalio: PID library using the FCAL cluster infomration is in developement for pi0 reconstruction. Similarly

        this is also done now for the BCAL. 

Elke: question about the geometry file to Richard

     he found some typoes etc. in the files he will shortly
     send information about this to the colaboration and eventually will update CVS.