Pythia Analysis ver 2.4: Cuts on all setC4 jobs

Effect of Cuts on Trigger Patch ET

In this analysis I look at the effect the cuts I used in Ver 2.3, as well as two new cuts, have on the transverse energy spectrum of the 3x3 trigger patch. For this analysis I used all files in setC4 for the QCD background and I used setC2_Wprod_N for the W samples. Details here.  I weighted all events to 800 inverse pb. As before the first four cuts restrict the energy range and the area of the endcap we look at and the final eleven cuts are  endcap and isolation cuts. The black curves are the QCD events and the red curves are the W events. All ET and eta's are event eta.

 

Here are the cuts: (Note, ordering different from ver 2.3)

 

  • Cut One: This cut requires that a reconstructed vertex is found, that the vertex lies in the range z=[-70,-50] and that the trigger patch ET be at least 15GeV.
  • Cut Two: This cut requires that the Trigger patch ET be greater than 20GeV.
  • Cut Three: This cut requires that the ET weighted average eta value of the trigger patch be less than 1.7.
  • CutFour: This cut requires that the highest energy tower be in etabin 6, 7, 8, 9, 10, or 11.
  • Cut Five: This is a cut on the ratio of the trigger patch ET to the total ET of all towers within a radius of 0.45 of the high tower. The cut was > 0.96 to pass.
  • Cut Six: This is a cut on the transverse distance between where a track crossed the endcap and the high tower. Counts over all tracks above 1GeV within a radius of 0.70 of the high tower. The Cut was < 0.07 to pass (fixed from Ver 2.3)
  • Cut Seven: (new) This is a cut on the transverse energy found in all towers (barrel and endcap) which lie in a region +/- 0.7 radians from Phi(hightower) + Pi. The cut was < 6.0 to pass.
  • Cut Eight: (new) This is a cut on the transverse distance between where a track crossed the endcap and the high tower. Counts over all tracks above 0.5 GeV within a radius of 0.70 of the high tower. The cut was < 0.07 to pass.
  • Cut Nine: This is a cut on the number of tracks above 1GeV which cross the endcap within a radius of 0.70 of the hightower. There must be 0 or 1 tracks to pass.
  • Cut Ten: This is a cut on the ratio of the energy in the seven highest SMD strips in the U plane under the patch to the energy in all the U strips under the patch. The cut was > 0.7 to pass.
  • Cut Eleven: This is a cut on the ratio of the energy in the two highest towers in the trigger patch to the energy in all the towers of the trigger patch. The cut was > 0.9 to pass.
  • Cut Twelve: This is a cut on the number of towers above 800 MeV in the sector (or sectors) containing the trigger patch. The cut was < 6 to pass.
  • Cut Thirteen: This is a cut on the number of hit strips in the U plane in the sector containing the high tower. The cut was < 48 to pass.
  • Cut Fourteen: This is a cut on the ratio of the post-shower energy in the patch to the full energy in the patch. The cut was < 0.0005 to pass.
  • Cut Fifteen: This is a cut on the post-shower energy in the patch. The cut was < 0.04 to pass.

 

Fig 1: This plot show the effects of all 15 cuts. The black line is the spectrum before any cuts are applied, the red line is the spectrum after the phase space cuts (1-4) are made, and the green line is the spectrum after all 15 cuts have been applied. QCD events are on the left and W events are on the right. For the QCD sample: The raw spectrum contains 718100 events in the region 20-60, the spectrum after the phase space cuts contains 452000 events, and the spectrum after all cuts contains 5215 events. For the W sample: The raw spectrum contains 3476 events in the region 20-60, the spectrum after the phase space cuts contains 1933 events, and the spectrum after all cuts contains 1407 events.

 

 

Fig 2: This plot shows the the QCD spectrum(black) after cuts 1-15 and the W spectrum(red)  after cuts 1-15 on the same figure.