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Run 9 200GeV Dijet: Investigating Additional Runs

Updated on Fri, 2013-08-16 17:15. Originally created by pagebs on 2013-08-13 21:53.

Here I look at the effect of adding additional runs to the cross section and asymmetry analyses ...

The results shown so far have used a run list containing only runs which exist in both data and simulation, this is the so called Strict Matching sample. I have recently started using the rel lumi and beam polarization files that Pibero used for the final inclusive jet asymmetry results. These files include 206 more runs than were used previously. 115 of these runs are between days 120 and 180 where simulation also exists. The list of all runs between days 120 and 180 is called the 120+ sample. The runs before day 120 are all production2009_200Gev_Hi and do not have associated simulation. There are 91 of these runs. The list of all runs is called the All Runs sample.

  • The strict matching sample contains 773 data runs with 17.1 pb^-1
  • The unmatched sample for runs between days 120 and 180 contains 115 runs with 2.3 pb^-1
  • The sample of runs between days 114 and 120 contains 91 runs with 1.5 pb^-1


I want to compare the strict matching sample to the day 120-180 unmatched sample and to the 114-120 sample.

 

Figure 1: This figure shows the raw data yields for the strict matching (Black), the unmatched (Red), and the pre-120 (Blue) samples normalized by the respective integrated luminosities and scaled by the correct phase space factors. The top pannel shows the spectra and the bottom pannel shows the ratio unmatched/Strict Matching samples (Red) and the ratio pre-120/Strict Matching samples (Blue).


 

Figure 2: Same as figure 1 but now the additional runs are combined. The black curve again shows the strict matching sample, the red curve now shows all runs (strict and unmatched) between days 120 and 180, the blue curve shows all runs between days 114 and 180. The bottom pannel shows the ratio 120+/Strict Matching (Red) and 114+/Strict Matching (Blue)

Figure 3: This figure shows the dijet mass spectra for different groups of days. Each spectra is normalized by its relative luminosity. The spectra for days greater than 120 are for all runs (strict and unmatched)

Figure 4: In this figure, I calculate the full cross section and compare to UEH corrected theory. The black curve was created using the strict matching sample, the red curve was created by combining the strict matching sample with the sample of unmatched runs from days 120-180, and the blue curve was created from all runs between days 114 and 180. The strict matching embedding files were used for the corrections for the black curve and all embedding files were used for the corrections for the red and blue curves.

As can be seen in the above figures, the runs from days 114-120 show a large deviation in luminosity scaled yield as compared to other periods. The discrepency follows the previously observed trend, but is even greater in magnitude. The next section explores whether there are discrepencies in the asymmetry measurement as well.

Figure 5: This figure shows the ALL for the strict matching sample (Blue), the unmatched 120-180 sample (Green), and the 114-120 sample (Black).

Figure 6: This figure shows the ALL as well, but now the Red points show the combination of the unmatched 120-180 and the strict matching samples. The Blue points are again the pure strict matching sample and the Black points are the 114-120 sample.

Figure 7: This figure shows the ALL. The Red and Blue points are the same as in figure 5 but now the Black points are the combination of Black, Blue, and Red points from figure 5, ie they show all runs from day 114 to day 180.

Figure 8: This figure shows the A_LL and the four false asymmetries determined from different subsets of the total run period as a function of dijet mass.





As can be seen, the A_LL for days 114-120 seem systematically below the other periods, but the false asymmetries for 114-120 don't appear very different from the rest of the runs.

 

 
 

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