| Type | Single pair | Double pair | Single w/had | Double w/had |
| BMU-only | .3821 | .06949 | .008444 | .001720 |
| Front | .0009507 | .0001132 | .0001811 | .00004527 |
| Rear either | .002037 | .0002716 | .0002943 | .00009055 |
| Rear both | .0001132 | .00004527 | .00002264 | 0 |
Looked at another way, if I require two pair in the trigger I get reduction rates as follows:
| Type | w/o had | w/ had trigger |
| BMU-only | 45.3 | 40.4 |
| Front | 8.4 | 4.0 |
| Rear either | 7.5 | 3.25 |
| Rear both | 2.5 | 0. |
"Rear either" is an alternative trigger requiring either rear BSU or rear TSU, "rear both" is the standard requiring both scintillators to fire.
Remember that this particular trigger cuts the Z sample in half, so reduction ratios of 2.5 are not very helpful in reducing the background.
Modified 20-July-2006 at 09:15
http://hep.physics.wisc.edu/~jnb/imu/20Jul2006