Extrapolation Techniques and Systematic Uncertainties in the NO$\nu$A Muon Neutrino Disappearance Analysis

The NOvA long-baseline neutrino experiment consists of two highly active, finely segmented, liquid scintillator detectors located 14.6 mrad off Fermilab’s NuMI beam axis, with a Near Detector located at Fermilab, and a Far Detector located 810 km from the target at Ash River, MI. NO$\nu$A released it first preliminary results of the muon neutrino disappearance parameters, measuring ${\sin }^2({\theta }_{23})=0.51\pm 0.10$ and or the normal hierarchy $\mathrm{\Delta }{m}_{32}^2=2.37_{-0.15}^{+0.16}\times {10}^{-3}$ eV${}^2$ and for the inverted hierarchy $\mathrm{\Delta }{m}_{32}^2=-2.40_{-0.17}^{+0.14}\times {10}^{-3}$ eV${}^2$. This talk will present a discussion of the systematic uncertainties and extrapolation methods used for this first analysis which uses $2.74\times {10}^{20}$ POT-equivalent collected between July 2013 and March 2015.