A measurement of material in the ATLAS tracker using secondary hadronic interactions in 7 TeV pp collisions

Abstract

Knowledge of the material in the ATLAS inner tracking detector is crucial in understanding the reconstruction of charged-particle tracks, the performance of algorithms that identify jets containing b-hadrons and is also essential to reduce background in searches for exotic particles that can decay within the inner detector volume. Interactions of primary hadrons produced in pp collisions with the material in the inner detector are used to map the location and amount of this material. The hadronic interactions of primary particles may result in secondary vertices, which in this analysis are reconstructed by an inclusive vertex-finding algorithm. Data were collected using minimum-bias triggers by the ATLAS detector operating at the LHC during 2010 at centre-of-mass energy $\sqrt{s}$ = 7 TeV, and correspond to an integrated luminosity of $19$ nb${}^{-1}$. Kinematic properties of these secondary vertices are used to study the validity of the modelling of hadronic interactions in simulation. Secondary-vertex yields are compared between data and simulation over a volume of about 0.7 m${}^3$ around the interaction point, and agreement is found within overall uncertainties.

arXiv comment28 pages plus author list + cover pages (45 pages total),14 figures, 8 tables, submitted to Journal of Instrum., All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/PERF-2015-06/

References in corpus (9)

• An Introduction to PYTHIA 8.2
• Parton distributions for the LHC
• The ATLAS Simulation Infrastructure
• EPOS LHC : test of collective hadronization with LHC data
• Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics
• Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC
• Search for massive, long-lived particles using multitrack displaced vertices or displaced lepton pairs in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• Search for long-lived, weakly interacting particles that decay to displaced hadronic jets in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• A measurement of the material in the ATLAS inner detector using secondary hadronic interactions

Cited by in corpus (11)

• Study of the material of the ATLAS inner detector for Run 2 of the LHC
• Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider
• Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in $\sqrt{s}$ = 13 TeV $pp$ collisions with the ATLAS detector
• Search for long-lived particles in final states with displaced dimuon vertices in $pp$ collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector
• Search for long-lived neutral particles produced in $pp$ collisions at $\sqrt{s}=13$ TeV decaying into displaced hadronic jets in the ATLAS inner detector and muon spectrometer
• Alignment of the ATLAS Inner Detector in Run-2
• Search for displaced vertices of oppositely charged leptons from decays of long-lived particles in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
• Precision measurement of the structure of the CMS inner tracking system using nuclear interactions
• Extending the LHC Reach for New Physics with Sub-Millimeter Displaced Vertices
• Searching for Metastable Particles with Sub-Millimeter Displaced Vertices at Hadron Colliders
• Measurements of charged-particle distributions with the ATLAS detector