User name R. Michaels
Log entry time 19:35:49 on February27,2006
Entry number 164278
Followups:
keyword=helicity info in datastreamSomebody asked, "is the helicity info in datastream ?
Answer is "yes and it looks ok -- nearly all the time."
Rich Holmes has been writing GenHelicity class and checking data.
I'll let him provide more details, but here is a quick look at
run 2400. The first ~3600 events are used to load the helicity
prediction algorithm. After that, an expected 1.6% of data have
"helicity==0" which is expected because the Pockel Cell flips in
500 microsec in a 30 msec helicity period (and helicity==0 means
we don't know the helicity). The GenHelicity did not report any
errors for this run (1st 20K events, analyzer is SLOW). Hopefully
this result is typical. And btw, to fill
this plot one should exclude T9, since they come at the helicity
transition (helicity==0) so it would increase the middle peak.
The histogram in fig 1 was filled for all other triggers which are
random w.r.t. helicity.
As for the disclaimer about "nearly all the time" I'll let Rich
update on this.
FIGURE 1
