Run 9 Vernier Scan BBC Cross Section: Second Look
Updated on Sat, 2014-10-18 14:42. Originally created by pagebs on 2014-10-02 23:16.
A more detailed look at the BBC cross section from Angelika and how it affects the normalized dijet yields ...
Figure 1: The BBC cross section values found by Angelika from the six vernier scans taken during the nominal 2009 200 GeV running. The points are plotted at the day the vernier scan was taken.
Figure 2: The ratios of the dijet mass spectra from days 120-129, 130-139, 140-149, 150-159, 160-169, and 170-179 to the mass spectra from day 170-179. In the top two panels, the mass spectra from each period are scaled by the number of BBCMB-Cat2 triggers recorded during that period. In the bottom two panels, the mass spectra from each period are scaled by the integrated luminosity (taking into account the changing BBC cross section, see explanation below) for that period. The left hand panels show the result using both the TPC and calorimeters, and the right hand panels show the result using only the calorimeters.
For the bottom panels of figure 2, the normalized yield in each period is calculated as follows:
Norm Dijet Yield = Raw Dijet Yield / Integrated Luminosity
Integrated Luminosity = Number of BBCMB-Cat2 Triggers / BBC Cross Section
The BBC cross section is calculated as a function of day using the form: 30.4-0.04736*Day. So the integrated luminosity is calculated for each day and then summed for each 10 day period.
For the above, I use the BBCMB-Cat2 trigger, but presumably, Angelika uses the scalar rates to calculate the cross sections. To make sure the trigger faithfully follows the trigger rates, I compare the BBCMB-Cat2 trigger counts to the accidentals and multiples corrected (using the modified TAC scheme) BBCX counts.
Figure 3: The ratio of BBCMB-Cat2 triggers to accidentals and multiples corrected (mod TAC scheme) BBCX vs runnumber for four fills. The red points are from day 128 (May 8), the blue points are from day 134 (May 14), the light green points are from day 146 (May 26), and the dark green points are from day 175 (June 24).
Figure 4: The ratio of accidentals and multiples corrected (mod TAC scheme) BBCX to VPDX vs runnumber for four fills.
Figure 1: The BBC cross section values found by Angelika from the six vernier scans taken during the nominal 2009 200 GeV running. The points are plotted at the day the vernier scan was taken.
Figure 2: The ratios of the dijet mass spectra from days 120-129, 130-139, 140-149, 150-159, 160-169, and 170-179 to the mass spectra from day 170-179. In the top two panels, the mass spectra from each period are scaled by the number of BBCMB-Cat2 triggers recorded during that period. In the bottom two panels, the mass spectra from each period are scaled by the integrated luminosity (taking into account the changing BBC cross section, see explanation below) for that period. The left hand panels show the result using both the TPC and calorimeters, and the right hand panels show the result using only the calorimeters.
For the bottom panels of figure 2, the normalized yield in each period is calculated as follows:
Norm Dijet Yield = Raw Dijet Yield / Integrated Luminosity
Integrated Luminosity = Number of BBCMB-Cat2 Triggers / BBC Cross Section
The BBC cross section is calculated as a function of day using the form: 30.4-0.04736*Day. So the integrated luminosity is calculated for each day and then summed for each 10 day period.
For the above, I use the BBCMB-Cat2 trigger, but presumably, Angelika uses the scalar rates to calculate the cross sections. To make sure the trigger faithfully follows the trigger rates, I compare the BBCMB-Cat2 trigger counts to the accidentals and multiples corrected (using the modified TAC scheme) BBCX counts.
Figure 3: The ratio of BBCMB-Cat2 triggers to accidentals and multiples corrected (mod TAC scheme) BBCX vs runnumber for four fills. The red points are from day 128 (May 8), the blue points are from day 134 (May 14), the light green points are from day 146 (May 26), and the dark green points are from day 175 (June 24).
Figure 4: The ratio of accidentals and multiples corrected (mod TAC scheme) BBCX to VPDX vs runnumber for four fills.
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