Upper plot (fig 1) shows Ws reconstructed from ~100% of Run9 data with algo ver 4.1 , now using away ET veto.

 CUTS ver 4.1  algo params: trigID: bht3=230531 L2W=230601  isMC=0
 TPC: nPileupVert>3, vertex |Z|<100.0cm, globEleTrack: nFit>15, hitFrac>0.51 Rin<90.0cm, Rout>170.0cm, PT>10.0GeV/c
 BTOW ADC: kSigPed=3 maxAdc>200 clustET>15.0 GeV  ET2x2/ET4x4>0.95  ET2x2/nearJetET>0.90
  dist(track-clust)<7.0cm,
 W selection highET>28.0 awayTotET<8.0GeV
 Z selection: highET>35.0GeV

Yellow histo contains both signs of W, blue histo is for negative sign.

Bottom plots shows charge sign discrimination based on global track component is decent up to ET~35 GeV, then degrades. Reconstruction of W+ & W- from separated M-C samples gives hint what should we expect for the data

The Jacobian peak  shown in Fig 1 is result of tuning of the W-algo. From now on only moderate  progress is expected. You can view it as preliminary result from Run9.

Charge sign discrimination will be better once vertex (and BSMD?) is used.

Run9 and  M-C results from W-algo ver 4.1

Fig 1	Fig 2	Fig 3	Fig 4	Fig 5
Run 9 data LT=~10/pb,  L2 trigger thresh>13 GeV	MC : QCD-Pythia, LT=6.3/pb, filter ET>20 GeV	MC : W-Pythia, LT=320/pb	MC : W plus ,Pythia, arb norm.	MC : W minus ,Pythia, arb norm.

Fig 6. 'Just' more data (recovered corrupted muDst) - now total input ~1.55M eve. The lower right shows e+/e- separation if the sign of primary track is used.  Integrals of yields on the right panels cover ET [30,50] GeV.

Fig 7. Subtracting exponential background , the same 1.5M events

Fig 8. DCA of glob track component to vertex. Top left: 3D. The other 2 shows charge separated signed DCA. The primary track charge was used. Run9 data from setB+C+D.

Fig 9. dEdX for all TPC tracks with PT>1 GeV on the left. For final W selection on the right. No evidence for e+e- pair from conversion of high pT gamma reconstructed as single TPC track with double dEdx. Run9 data from setB+C+D.

Fig 10. Repeated (and cleaned up) Q/PT analysis w/o ET cut on 2x2 cluster energy.

plot bottom right shows that in the 15-20 GeV region we see _no_ significant yield difference between charge states, and that this +/- enhancement really kicks in just where Fig. 7 suggests we are starting to be dominated by W's rather than QCD bkgd.

Scott comments: I agree that we have a rapidly falling pt spectrum - but what is plotted is 1/pt vs the E_T measured in the calorimeter, and the latter shouldn't care if the particle is + or -. So the fact that we still see about 50% more yield for + charge than for - charge, in a given E_T bin below 25 GeV, bothers me. Even if the pt extracted from the TPC is systematically shifted up for + and down for -, this will shift the 'locus' of points up and down on the plots, but should not shift particles in or out of a given E_T bin. So I'm glad Jan stayed up late and made the plots, though it is not as encouraging as I had hoped. If we can't understand the +/- ratio below 20 GeV, we shouldn't believe we understand the W+/W- ratio above 30 GeV.
It's still possible, and maybe even likely, that this is real physics. Though we believe the yield below 20 GeV is dominated by di-jets, these are di-jets where the near-side jet contains a single particle with a large fraction of the jet energy - after all, it must satisfy all of the W cuts. In a pp collision, it may be that if a jet has a very high-z leading particle, that particle is more likely to be positive than negative. This is something we need to look at closely in simulation ... but not before tomorrow.

Fig 11. COmparison of near jet ET cut for run9 data (left), M-C QCD (middle) , and M-C W-events (right)

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Fig 12. Background study. Run 9 data show. Change only gate on the nearCone ET ratio (shown on fig 11) to be: left=[0.9,1.], middle=[0.8,0.9], right=[0.7,0.8]