Light-quark and gluon jet discrimination in collisions at root s=7 TeV with the ATLAS detector
Number of Authors: 2880
2014 (English)In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 74, no 8, UNSP 3023- p.Article in journal (Refereed) Published
A likelihood-based discriminant for the identification of quark- and gluon-initiated jets is built and validated using 4.7 fb −1 of proton–proton collision data at s√=7 TeV collected with the ATLAS detector at the LHC. Data samples with enriched quark or gluon content are used in the construction and validation of templates of jet properties that are the input to the likelihood-based discriminant. The discriminating power of the jet tagger is established in both data and Monte Carlo samples within a systematic uncertainty of ≈ 10–20 %. In data, light-quark jets can be tagged with an efficiency of ≈50% while achieving a gluon-jet mis-tag rate of ≈25% in a pT range between 40 GeV and 360 GeV for jets in the acceptance of the tracker. The rejection of gluon-jets found in the data is significantly below what is attainable using a Pythia 6 Monte Carlo simulation, where gluon-jet mis-tag rates of 10 % can be reached for a 50 % selection efficiency of light-quark jets using the same jet properties.
Place, publisher, year, edition, pages
2014. Vol. 74, no 8, UNSP 3023- p.
IdentifiersURN: urn:nbn:se:uu:diva-233697DOI: 10.1140/epjc/s10052-014-3023-zISI: 000340948500001OAI: oai:DiVA.org:uu-233697DiVA: diva2:753660
ATLAS Collaboration, for complete list of authors see http://dx.doi.org/10.1140/epjc/s10052-014-3023-z2014-10-082014-10-082014-10-08Bibliographically approved