Performance of the ATLAS Detector using First Collision Data

TL;DR

This paper evaluates the initial performance of the ATLAS detector using early collision data from the LHC at 0.9 and 2.36 TeV, demonstrating good detector operation and agreement with predictions.

Contribution

It provides the first performance assessment of the ATLAS detector with real collision data, validating its readiness for higher energy runs.

Findings

Detector performance matches Monte Carlo simulations

Good data quality and detector stability confirmed

Confidence established for future high-energy collisions

Abstract

More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-of-mass energies of 0.9 TeV and 2.36 TeV. This paper reports on studies of the initial performance of the ATLAS detector from these data. Comparisons between data and Monte Carlo predictions are shown for distributions of several track- and calorimeter-based quantities. The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies.