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Some Luminosity Statistics

Updated on Wed, 2007-08-01 15:45. Originally created by kocolosk on 2007-07-29 22:23.
===========================================================================================
trigId L_int_mb ε_vtx ε_mb vz vz_mb L_samp_mb < ps > L_sampled
-------------------------------------------------------------------------------------------
117001 4.794 pb^-1 0.505 0.505 0.678 0.678 6.191 μb^-1 1.0 6.191 μb^-1
137221 111.932 nb^-1 0.876 0.475 0.622 0.679 360.330 mb^-1 24894.4 8.970 nb^-1
137222 4.682 pb^-1 0.936 0.507 0.616 0.678 5.830 μb^-1 35544.9 207.237 nb^-1
137611 3.606 pb^-1 0.896 0.500 0.641 0.675 2.620 μb^-1 39894.6 104.544 nb^-1
137622 4.682 pb^-1 0.977 0.507 0.637 0.678 5.830 μb^-1 24114.8 140.597 nb^-1
===========================================================================================

where

  • L_int_mb is the integrated luminosity seen by the minbias trigger for runs in which the specified trigger was active
  • eps_vtx is the vertex finding efficiency for this trigger
  • eps_mb is the vertex finding efficiency for mb-triggered events in runs in which the specified trigger was active
  • vz is the fraction of events with a reco vertex that had fabs(vz) < 60 cm
  • vz_mb is the same quantity for mb triggered events
  • L_samp_mb is N_good_vertex_mb / (eps_mb * sigmaBBC))
  • < ps > is sum_{runs} (ps_mb * n_mb) / sum_{runs} (ps_trig * n_trig)
  • L_sampled is L_samp_mb * < ps >

Data were obtained from the 289 spinTree runs without any additional QA selection.  If I restrict to the 188 runs in the latest jet runlist I get

===========================================================================================
trigId L_int_mb ε_vtx ε_mb vz vz_mb L_samp_mb < ps > L_sampled
-------------------------------------------------------------------------------------------
117001 003.286 pb^-1 0.513 0.513 0.676 0.676 4.757 μb^-1 1.0 4.757 μb^-1
137221 065.594 nb^-1 0.957 0.518 0.625 0.683 208.913 mb^-1 24838.9 5.189 nb^-1
137222 003.220 pb^-1 0.942 0.512 0.613 0.676 4.548 μb^-1 36362.2 165.371 nb^-1
137611 002.253 pb^-1 0.905 0.510 0.636 0.669 1.649 μb^-1 40234.9 066.358 nb^-1
137622 003.220 pb^-1 0.981 0.512 0.637 0.676 4.548 μb^-1 24376.0 110.859 nb^-1
===========================================================================================

The vertex finding efficiency for minbias triggers climbs a little bit, but it's still only 51%.  After doing a little digging it seems this is consistent with Jan's findings in his evaluation of PPV for 2006:

http://www.star.bnl.gov/HyperNews-star/protected/get/starspin/2820.html

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