e/  Final state Jaewon Park University of Rochester

2 Overview Have been trying to separate nu_e event from b ackground event with various techniques.  Just check each variable seperately Electron track showers.  Ratio of nStrip of track  Primary vertex to track distance Pt imbalance  Transverse momentum will be close to zero in nu_e eve nt. Try to combine altogether to get overall rejection power.  Currently only done with nu_e data sample.

3 Ratio of track end’s nSt rip over track begin’s n Strip Track begin=first 2/3 of track Track end =last 1/3 of t rack electronproton True primary vertex to t rack distance Reco primary vertex to track distance It requires at least two r econstructed tracks

4 Fraction of reconstructed electron track Fraction of reconstructed electron track when nStrip ratio > 1.2

5 True primary vertex to track distance < 10cm Fraction of reconstructed electron track when number of reconstructed track >= 2

6 Fraction of reconstructed proton track Fraction of reconstructed electron track: nRecon >= 2, nStrip ratio>1.2 and reco PV to track dist <10cm

7 Pt imbalance When at least t wo tracks are r econstructed Pt sum of first t wo track out of all tracks(>=2). Pt using true v alue. Nu_e Nu_mu Cut: Pt<250MeV/c

8 nRecon>2 nStrip ratio>1.2 pT < 250 MeV nRecon>2 nStrip ratio>1.2 Reco PV to track<10cm pT < 250 MeV