User name Templon
Log entry time 18:40:46 on October 9,2000
Entry number 49935
This entry is a followup to: 49931
Followups:
keyword=notes for trigger setting at D,E,F kinematicsFor D,E,F kinematics, it may be more challenging to discover the correct
timing peak. One tack you can take is (for E and F kinematics) to take
a 10 cm dummy run very early in the program, and use this to refine your
reactz difference cut (see ek/checkc.kumac). However this may still
not be enough. So here is a guide for how to set the delay:
.
for Py-2C,2D,2E,2F -- the last setting (1700-4000) should be OK.
For Py-2B,2A will likely have to change. Also, we may have to do
something at the hardware level for the highest setting, since we are
getting a bit too close to the edge for the highest momenta that will be
encountered at these kinematics.
.
The plot below illustrates the problem. The second peak in tc spectrum
is at about channel 193, and Bob predicts that the peaks will slide to
the right by 9.2 ns as we move to PY-1F. This puts the satellite peak
centroid at 202.5, with 3sigma at 206.7. 208 looks like the edge of
the flat portion. Bob, can you make the good part of the bucket slide
over a bit to the right (like 8 ns or so?).
.
Here is a table of predicted peak positions, based on the current setting
and on bob's program:
setting mom(p) peak hdelay
py-2A 1105 [173.9] 26.5
py-2B 1249 [179.1] 21.3
py-2C 1419 183.5 16.9
py-2D 1627 [187.3] 13.1
py-2E 1899 [190.6] 9.8
py-2F 2154 [192.7] 7.7
The peak positions in brackets are predicted values.
FIGURE 1
