ATLAS measurements of the properties of jets for boosted particle searches

TL;DR

This paper reports measurements of high transverse momentum jet properties in proton-proton collisions at 7 TeV, comparing results to Monte Carlo simulations to evaluate their accuracy in modeling jet characteristics.

Contribution

It provides the first detailed measurements of jet substructure variables for boosted jets at 7 TeV, testing and highlighting discrepancies in Monte Carlo models.

Findings

Generators generally match jet features but show discrepancies in some distributions.

Jet mass, width, eccentricity, planar flow, and angularity are measured for R=0.6 and 1.0.

Results help improve modeling of high-pT jets in collider experiments.

Abstract

Measurements are presented of the properties of high transverse momentum jets, produced in proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV. The data correspond to an integrated luminosity of 35 pb^-1 and were collected with the ATLAS detector in 2010. Jet mass, width, eccentricity, planar flow and angularity are measured for jets reconstructed using the anti-kt algorithm with distance parameters R = 0.6 and 1.0, with transverse momentum pT > 300 GeV and pseudorapidity |eta| < 2. The measurements are compared to the expectations of Monte Carlo generators that match leading-logarithmic parton showers to leading-order, or next-to-leading-order, matrix elements. The generators describe the general features of the jets, although discrepancies are observed in some distributions.