Run 9 200GeV Dijet Data Test

Here I look at the full RFF+FF reproduced run 9 data sample ...

One new feature I implemented in the last round of detector/particle level jet comparisons was that I relaxed the condition that jets in the barrel must have a neutral fraction less than 0.95. In its place I required that both jets could not have a neutral fraction of 1.0. There was some concern that this cut would discard a large number of events in which both jets were far forward. If both jets have det Eta >= 1.5 for example, this cut removes 434 events while 2727 events remain, so we lose roughly 13.7% (434/(434+2727)) of the total events in this region. The losses in all other regions of the detector are less than 1%.

Figure 1: This plot shows the low pt vs high pt jet detector eta. The top pannel shows dijet events for which both jets have a neutral fraction of 1.0 and are therefor discarded. The bottom pannel shows dijet events for which at least one jet had a neutral fraction less than 1.0 and are therefor analyzed. 

Some other cuts I am considering are a limit on the maximum pt a jet is allowed to have as well as a possible pt balance cut. Figure 2 below shows that there are some obvious high pt tails which should be discarded. It is not currently obvious if a pt balance cut is needed.

Figure 2: This figure shows the away side vs same side jet pts for the eight valid trigger combinations for dijet events. (The same side jet is the triggered jet, if both jets are triggered it is the jet with higher pt. The away side jet is the jet which is not the same side jet.)

I also have a pdf which shows the away vs same side jet pt divided by topology and by topology and trigger category simultaneously.