more on event classifications...

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From: W.J. Llope (llope_at_physics.rice.edu)
Date: Fri Jan 24 2003 - 17:10:52 EST

this is from the runs last night where i saw the relatively
lower "local trigger efficiency" of ~13%... there are ~20.1k
localmon events in this file....

see http://mac8.rice.edu/~TOF/TOFp/hfcondition.gif

plotted is # of events versus a bitpattern filled via:
        for(int i=0;i<5;i++){ conditions[i]=false;}
        if (sca[09] ){ conditions[0]=true; }
        if (sca[10] ){ conditions[1]=true; }
        if (tdc0[0]>970&&tdc0[0]<1110){ conditions[2]=true; }
        if (sca[00] ){ conditions[3]=true; }
        if (tdc0[0]>3799
           ||tdc0[1]>3799
           ||tdc0[2]>3799 ) {conditions[4]=true; }
        fcondition = 0.;
        for(int i=0;i<5;i++){
                if (conditions[i]){ fcondition += (Float_t)(2**i); }
// cout <<" "<<(Int_t)conditions[i];
        }
// cout <<" "<<(Int_t)fcondition << endl;
        hfcondition->Fill(fcondition);

from which:

fcondition no. of events
    0 2
    7 ~8k
    8 1
   12 5
   15 ~9k
   25 ~3k <--<< "physics events"

fcondition=7 (11100) means
        scaler[9] = scaler[10] = 1
        tdcs are at "test-stop" values near 1000
        scaler[0] (pvpd singles) = 0

fcondition=15 (11110) means
        scaler[9] = scaler[10] = 1
        tdcs are at "test-stop" values near 1000
        scaler[0] (pvpd singles) is >0

fcondition=25 (10011) means
        scaler[0] is >0
        tdc overflows seen
        scaler[9] = 1, scaler[10] = 0

i've been calling the fcondition=25 events
the physics events, and that 3k/20k is the ~13%
'local trigger efficiency' i've been quoting...

i guess what i'm not clear on is what exactly are these
(approximately equal amounts) of fcondition=7 and =15
events???
they are the same in that all the tdcs are near 1000
and all adcs at pedestal, yet for the =7 case
the pvpd singles scalers are zero, and for the =15 case
they are non-zero.....

comments?
        bill 

-- 

  W.J. Llope, Ph.D.                      Res. Assoc. Professor
  T.W. Bonner Nuclear Laboratory         phone:  713-348-4741
  Rice University, MS-315                fax:    713-348-5215
  6100 S. Main St.
  Houston, TX 77005-1892
             e-mail:     llope_at_physics.rice.edu
             WWW home:   http://wjllope.rice.edu/default.html

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