Performance of the E789 Processor for the D data sample
                  mjl - 3/16/94
               corrected - 4/14/94

Processor Rejection Factor:

   Data      Tape   Trg   Evts    Fthru   Pass   Rej.
  -------   ------  ----  -----   -----   ----   ----
  900A Be   ln4214  all   99991   27672   1169   23.7
   "  "      "  "   h+h-  71463   14044    921   15.2
  900A Au   ln4225  all   99992    7684   1440    5.3
   "  "      "  "   h+h-  88233    5515   1286    4.3
  1000A Au  ln3214  all   99999   16704   1280   13.1
   "  "      "  "   h+h-  85165   10792   1128    9.6

(The overall rejections from the scalers including force-thrus
for the complete data samples are 900A Be: 18, 900A Au: 5, and
1000A Au: 4.7. These are different because they average over
the entire data samples, not just part of one tape.)


Efficiency for D's:

  Processor force-thru events from most of data were analyzed with the same
  cuts used for the normal D analysis including vertex cuts. Then
  a mass cut to select events near the D mass was made. If we assume that
  these events are representative of the real D events (i.e. they have
  similar momentum resolution and vertex) then the processor efficiency is
  given by the number of these events which also pass the processor.
                        efficiency        lost due to hardware errors
                     -------------------  ---------------------------
          900A Be    200/270 = .74+/-.05             4
          900A Au    250/356 = .70+/-.04            30
         1000A Au    514/719 = .71+/-.04             ?
         1000A Au
   (no proc. cut)    31/49   = .66       (real D's)
                       same              (all events at D mass)
   Simulation of the processor with Ron Jeppeson's simulation program
   (works with the regular Monte Carlo) using drift chamber and silicon
   efficiencies determined above yields about .79, not too far from the
   values measured above. Comparison of the simulation on real data with
   the hardware processors results show that for parts of the data the
   processor was not working properly (see the last column above). This
   presumably explains some of the remaining discrepancy between the
   simulation and the real processor.

   After varying the mass cut and the Tau/sig cut I have concluded that
   the uncertainty on the processor efficiency is indeed smaller than
   I had previously quoted, e.g. about .02/.74 for 900A Be.
 
   mass             900A Be                    900A Au
   cut(GeV) 1.82-1.90 1.66-2.06   none     1.82-1.90 1.66-2.06   none
            --------- --------- --------   --------- --------- --------
   >6.25    .74(.05)  .73(.03)  .74(.02)   .70(.05)  .72(.03)  .71(.02)
   >9.5     .81(.11)  .77(.06)  .75(.04)   .66(.09)  .70(.05)  .72(.03)
   >12.5    .86(.18)  .78(.09)  .75(.07)   .78(.18)  .72(.08)  .74(.06)
   >15.5    .88(.24)  .76(.12)  .75(.10)   .73(.22)  .70(.11)  .71(.08)




Multiplicity for D data - Rates (per event):

               L(/cm2/sec)
                 on tgt.
     Target     instant.   Silicon     DC1      DC2      DC3
     --------   ---------    -------   -------  -------  -------
     900A Be     1.9e32      5.7-7.5   6.3-9.9  4.2-4.5  6.4-7
     900A Au     3.2e32      7.9-11.9  4.8-8.7  3.5-3.7  4.9-5.1
     1000A Au    3.4e32      7.0-12.6  5.2-9.9  4.3-4.5  6.1-6.8

Compare hardware and software processor for downstream events:

      Data     Pfile   Correct
     -------   -----  ---------------
     900A Be    705   330/341 = 0.968
      "  "      706   939/954 = 0.984
     900A Au    702   849/872 = 0.974
      "  "      706  1426/1483 = 0.962