(q/p) / (σ q/p) 0 < Planes < 3030 <= Planes < 6060 <= Planes < <= Planes < <= Planes < 153  Separation is better for longer events ! 1) NuBarPID improvement with 2D histogram

 So tried the following 2D PDFs for the NuBarPID (in addition to #planes, y, and dcosz) neutrinosantineutrinos Note: Every “row”, or slice of planes (for instance from 0 to 30) is normalized to unity, as seen in previous slide. This is to keep the effect of the #planes PDF separate (and not be E dependent)

 A slight improvement is observed ! Why two peaks for neutrinos? After Before After Purity Efficiency nu nubar

First Checked that subroutine used to determine whether a muon stopped or not in the detector is working. Looked at track end position: Things that stop  Things that do not stop  y (m) x (m) y (m) x (m) z (m) 2) Effect of a cut on

In order to analyze performance of making a cut on stoppers, the following was done: Use 4 NuBarPID with 4PDFs: 1) the 2D q/p/(σ q/p) vs. planes histogram 2) planes 3) y 4) cosz The pdfs were made with no cuts required, except basic track quality ones: At least 1 track Trk.fit.pass==1 U-V asym < 6 /ndf < 20 Plots of Purity vs. Efficiency were made. The efficiency now includes all cuts (including the basic track quality ones, and the one). In other words, efficiency is measured with respect to all CC nubar events.

No extra cut x=1.0 x=0.5 x=0.3 x=0.15

3) Effect of other cuts Attempted Jeff H’s cut of Prob(, ndf) > 0.1. It works pretty good for high purity!!!!  Any other cuts to try? No extra cut x=0.15 cut Prob(chi2,ndf)>0.1 cut