Oct 2017 - Sep 2018

Precision EW Measurements from ATLAS - Towards Extracting sin^2 theta_eff

by Eram Rizvi (Queen Mary)


The phenomenal operation of the LHC in Run-1 has allowed high
precision measurements to be attained for single vector boson
production in pp collisions. A new measurement of the cross section
for Z\gamma production at \sqrt{s}=8 TeV will be presented triple
differentially in dilepton invariant mass, |y| and \cos\theta covering
the region 46<m<200 GeV; 0<|y|<3.6; and -1<cos\theta<+1. The
measurement is designed to be simultaneously sensitive to the proton
PDFs and to the weak mixing angle. A precision of better than 0.5% in
the region m~mZ (excluding luminosity uncertainty) is achieved. An
unfolded measurement of the Z forward-backward asymmetry is presented,
and a novel method of extracting the effective weak mixing angle using
this data will be discussed, together with plans from ATLAS to test
the consistency of the EW sector of the Standard Model.