1. Tracking systematics:new routine ready for tests Andrea Venturi INFN Pisa Tracking systematics - Andrea Venturi - WW meeting in Pisa

2. Status Report • Target: • new routine to apply biases and smearing to all charged tracks momenta and direction in a realistic and correlated way. • What has been done so far: • Showing that momentum and azimuth biases are, indeed, correlated • (W meeting on April 1st) • Measuring momentum biases with the standard “sagitta correction” technique • finer binning in theta and phi • di-muons at Z peak for absolute biases • bhabha’s at HE for relative biases as a function of the azimuth • Estimating the azimuth bias from the momentum bias • Preparing a routine which applies these biases in an ALPHA job • Produce the ntuples of 200k WW events (207 GeV) with these biases • momentum and azimuth biases • momentum and azimuth biases + sagitta corrections Tracking systematics - Andrea Venturi - WW meeting in Pisa

3. Momentum bias: p/p2 (GeV-1): 2000 data Tracking systematics - Andrea Venturi - WW meeting in Pisa

4. Azimuth bias:  p/p2 (rad) Tracking systematics - Andrea Venturi - WW meeting in Pisa

5.  2000 Z data  biased  MC Tracking systematics - Andrea Venturi - WW meeting in Pisa

6. electron Eb/p positron Eb/p  2000 Bhabha data  biased Bhabha MC very forward regions acoplanarity Tracking systematics - Andrea Venturi - WW meeting in Pisa

7. Conclusions • Preliminary results: • 4q (Ann) • M=-0.5+/-0.8 MeV • eqq (Guillaume) • M 2 MeV • this should replace both sagitta correction systematics and lepton azimuth bias systematics • To be tested/checked • Am I really biasing charged eflow objects as well ? (not tested yet…) • why are biases from bhabha and muons different in forward region ? • another set of biases ? • To be done • 1997 data biases have to be rebinned (low statistics) • add momentum and azimuth resolution simulation • add polar angle bias and resolution simulation • check data vs MC jet/lepton discrepancies used for ad hoc shaking/smearing Tracking systematics - Andrea Venturi - WW meeting in Pisa