Measurement of the ttbar Interaction Cross Section in the tau+jets Decay Channel via Multivariable Template Fitting of 4.6 fb^{-1} of data collected at √s = 7 TeV by the ATLAS Detector

This analysis measured the entire ttbar cross section through the specific decay channel to a tau, tau neutrino and four quark jets utilizing the full 2011 ATLAS collected data sample of 4.6fb^{-1}. Measurement was achieved by creating templates based on Monte Carlo samples for the various well-modeled background and signal in conjunction with a data-driven derived template for QCD multijet samples. Signal separation was achieved by utilizing Boosted Decision Tree multi-variables designed to identify true from fake taus. The final result was determined to be 165.8 ±9.9 (𝑠𝑡𝑎𝑡.)− 30.0+ 29.7(𝑠𝑦𝑠𝑡.)±3.0(𝑙𝑢𝑚𝑖.) pb which is in agreement with previous measurements of this cross section both within and beyond this decay channel as well as Standard Model predictions.