ZZ->4l – Differential Binning

1. ZZ->4l – Differential Binning Nick Edwards, University of Glasgow Nick Edwards

2. Introduction • Want to measure differential cross sections in pT(Leading Z), pT(Leading Lepton), m(ZZ). • With 62 events we’re still pretty limited in statistics. • In each bin we need CZZ, Nobs, Nbkg. • For TGC limits, we want a binning coarse enough to give information about events (or lack of) in the high tails of the spectrums, but we need enough stats in MC to predict what we expect to see there (and the systematic). • Suggested binning: • M(4l)               : 0-240, 240-300, 300-400, 400-600, 600+ • Pt(lead Z)        : 0-60   , 60-100,  100-200, 200-400, 400+   • Pt(lead lepton) : 0-60,    60-100,   100-150, 150-250, 250+ Nick Edwards

3. MZZ • Left: Coarsely binned, Right: Proposed differential binning Nick Edwards

4. PT (Leading lepton) • Left: Coarsely binned, Right: Proposed differential binning Nick Edwards

5. PT(Leading Z) • Left: Coarsely binned, Right: Proposed differential binning Nick Edwards

6. CZZ in differential bins - MZZ • From Sherpa 1parton MC11c sample (126148). • Errors are stat only. Apart from 4e channel, error is 3% in highest bin (cf 2% overall in published analysis). For 4e, ~8% in highest bin (cf 8% in published analysis) Nick Edwards

7. CZZ in differential bins PT(Leading Lepton) • From Sherpa 1parton MC11c sample (126148). • Errors are stat only. For all channels combined, error is ~ 6% in highest bin (cf 3% overall in published analysis). For 4e, ~17% in highest bin (cf 8% in published analysis) Nick Edwards

8. CZZ in differential bins – Z1(PT) • From Sherpa 1parton MC11c sample (126148). • Errors are stat only. For channels combined, error is ~15% in highest bin (cf 3% overall in published analysis). For 4e, ~35% in highest bin (cf 8% in published analysis) • Need to rethink binning here maybe! Nick Edwards