MuDst based track investigation ...

I have developed some code which looks at the high pt track problem using the MuDsts. This will allow me to look at the high pt tracks without any biases which may be introduced by running the jet finder. It will also allow me to do QA checks on MuDsts from any upcomming reproduction without having to run the jet finder.

The plots below show tracks from the first primary vertex. The z position of the vertex was required to be between +/- 90 cm. I have also imposed the track cuts used in the jet finder:

• track flag > 0
• # of Hits > 12
• # Hits / # Possible Hits >= 0.51
• 0 <= chi2 <= 4.0
• pt > 0.2 GeV
• -2.5 <= eta <= 2.5
• 0.0 <= TDCA <= 3.0
• Pt Dependant DCA cut

I have also divided the tracks by trigger. I look at events which fire the BBCMB trigger and events which fire either the L2JetHigh or JP1 trigger. I also looked at ZDCMB events, but there where far fewer ZDCMB tracks than for the other triggers, I am not sure why that is. 

Figure 1: This figure shows the track distribution in eta and phi for RFF runs (left column) and FF runs (right column). Events which fired the BBCMB trigger are on top and events which fired the L2JetHigh or JP1 triggers are on bottom.

Figure 2: This figure shows the track pt spectra from all sectors. The pannels show RFF runs (left column) and FF runs (right column). Events which fired the BBCMB trigger are on top and events which fired the L2JetHigh or JP1 triggers are on bottom.

Figure 3: This figure shows the track Phi vs the track Pt for events which fired the L2JetHigh or JP1 triggers. The sector 20 enhancement is evident between phi = 0 and phi = -1.

Figure 4: This figure shows the first (top) and last (bottom) track hit point in the TPC for tracks in certain pt ranges. The events are from the L2JetHigh and JP1 triggers

Figure 5: This figure shows the positive (red) and negative (blue) charge sign track pt spectra for the RFF runs (upper left) and the FF runs (upper right). The bottom pannels show the h-/h+ ratios for the RFF and FF runs. The spectra include all TPC sectors.

Figure 6: This figure again shows the h-/h+ spectra and ratios, but now the spectra are divided into East and West TPC sectors. The top pannels show the RFF runs and the bottom pannels show the FF runs. The left pannels are the East TPC sectors, the middle pannels are the West TPC sectors and the right pannels are the h-/h+ ratios. The black curves are the East TPC ratios and the green curves are the West TPC ratios.

I have also created plots of the h-/h+ spectra and ratios for each TPC sector seperately. The plots can be found in this pdf. Plots showing the RFF and FF positive and negative track pts for each sector can be seen in this pdf. These plots are for events which fired the L2JetHigh or JP1 triggers.