A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV

<jats:title>Abstract</jats:title> <jats:p>Many measurements at the LHC require efficient identification of heavy-flavour jets, i.e. jets originating from bottom (b) or charm (c) quarks. An overview of the algorithms used to identify c jets is described and...

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Main Author: Harris, Philip
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:English
Published: IOP Publishing 2022
Online Access:https://hdl.handle.net/1721.1/142121
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author Harris, Philip
author2 Massachusetts Institute of Technology. Department of Physics
author_facet Massachusetts Institute of Technology. Department of Physics
Harris, Philip
author_sort Harris, Philip
collection MIT
description <jats:title>Abstract</jats:title> <jats:p>Many measurements at the LHC require efficient identification of heavy-flavour jets, i.e. jets originating from bottom (b) or charm (c) quarks. An overview of the algorithms used to identify c jets is described and a novel method to calibrate them is presented. This new method adjusts the entire distributions of the outputs obtained when the algorithms are applied to jets of different flavours. It is based on an iterative approach exploiting three distinct control regions that are enriched with either b jets, c jets, or light-flavour and gluon jets. Results are presented in the form of correction factors evaluated using proton-proton collision data with an integrated luminosity of 41.5 fb<jats:sup>-1</jats:sup> at  <jats:italic>√s</jats:italic> = 13 TeV, collected by the CMS experiment in 2017. The closure of the method is tested by applying the measured correction factors on simulated data sets and checking the agreement between the adjusted simulation and collision data. Furthermore, a validation is performed by testing the method on pseudodata, which emulate various mismodelling conditions. The calibrated results enable the use of the full distributions of heavy-flavour identification algorithm outputs, e.g. as inputs to machine-learning models. Thus, they are expected to increase the sensitivity of future physics analyses.</jats:p>
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spelling mit-1721.1/1421212024-01-02T20:49:39Z A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV Harris, Philip Massachusetts Institute of Technology. Department of Physics <jats:title>Abstract</jats:title> <jats:p>Many measurements at the LHC require efficient identification of heavy-flavour jets, i.e. jets originating from bottom (b) or charm (c) quarks. An overview of the algorithms used to identify c jets is described and a novel method to calibrate them is presented. This new method adjusts the entire distributions of the outputs obtained when the algorithms are applied to jets of different flavours. It is based on an iterative approach exploiting three distinct control regions that are enriched with either b jets, c jets, or light-flavour and gluon jets. Results are presented in the form of correction factors evaluated using proton-proton collision data with an integrated luminosity of 41.5 fb<jats:sup>-1</jats:sup> at  <jats:italic>√s</jats:italic> = 13 TeV, collected by the CMS experiment in 2017. The closure of the method is tested by applying the measured correction factors on simulated data sets and checking the agreement between the adjusted simulation and collision data. Furthermore, a validation is performed by testing the method on pseudodata, which emulate various mismodelling conditions. The calibrated results enable the use of the full distributions of heavy-flavour identification algorithm outputs, e.g. as inputs to machine-learning models. Thus, they are expected to increase the sensitivity of future physics analyses.</jats:p> 2022-04-27T14:13:30Z 2022-04-27T14:13:30Z 2022-03-01 2022-04-27T14:05:43Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/142121 Harris, Philip. 2022. "A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV." Journal of Instrumentation, 17 (03). en 10.1088/1748-0221/17/03/p03014 Journal of Instrumentation Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf IOP Publishing IOP Publishing
spellingShingle Harris, Philip
A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title_full A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title_fullStr A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title_full_unstemmed A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title_short A new calibration method for charm jet identification validated with proton-proton collision events at √s = 13 TeV
title_sort new calibration method for charm jet identification validated with proton proton collision events at √s 13 tev
url https://hdl.handle.net/1721.1/142121
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