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A new method to distinguish hadronically decaying boosted Z bosons from W bosons using the ATLAS detector

Aad, G; Abbott, B.; Abdallah, J.; Abdinov, O; Aben, R; Abolins, M; Åkesson, Torsten LU ; Bocchetta, Simona LU ; Bryngemark, Lene LU and Doglioni, Caterina LU , et al. (2016) In European Physical Journal C 76(5).
Abstract
The distribution of particles inside hadronic jets produced in the decay of boosted W and Z bosons can be used to discriminate such jets from the continuum background. Given that a jet has been identified as likely resulting from the hadronic decay of a boosted W or Z boson, this paper presents a technique for further differentiating Z bosons from W bosons. The variables used are jet mass, jet charge, and a b-tagging discriminant. A likelihood tagger is constructed from these variables and tested in the simulation of W′→ WZ for bosons in the transverse momentum range 200 GeV < pT< 400 GeV in s= 8 TeV pp collisions with the ATLAS detector at the LHC. For Z-boson tagging efficiencies of ϵZ= 90 , 50, and 10 % , one can achieve W+-boson... (More)
The distribution of particles inside hadronic jets produced in the decay of boosted W and Z bosons can be used to discriminate such jets from the continuum background. Given that a jet has been identified as likely resulting from the hadronic decay of a boosted W or Z boson, this paper presents a technique for further differentiating Z bosons from W bosons. The variables used are jet mass, jet charge, and a b-tagging discriminant. A likelihood tagger is constructed from these variables and tested in the simulation of W′→ WZ for bosons in the transverse momentum range 200 GeV < pT< 400 GeV in s= 8 TeV pp collisions with the ATLAS detector at the LHC. For Z-boson tagging efficiencies of ϵZ= 90 , 50, and 10 % , one can achieve W+-boson tagging rejection factors (1 / ϵW+) of 1.7, 8.3 and 1000, respectively. It is not possible to measure these efficiencies in the data due to the lack of a pure sample of high pT, hadronically decaying Z bosons. However, the modelling of the tagger inputs for boosted W bosons is studied in data using a tt¯ -enriched sample of events in 20.3 fb- 1 of data at s= 8 TeV. The inputs are well modelled within uncertainties, which builds confidence in the expected tagger performance. © 2016, CERN for the benefit of the ATLAS collaboration. (Less)
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European Physical Journal C
volume
76
issue
5
publisher
Springer
external identifiers
  • scopus:84964889939
ISSN
1434-6044
DOI
10.1140/epjc/s10052-016-4065-1
language
English
LU publication?
yes
id
78cd86d6-6430-4fb3-8b6d-0c498e8b2c44
date added to LUP
2018-05-24 11:36:25
date last changed
2019-10-15 06:38:41
@article{78cd86d6-6430-4fb3-8b6d-0c498e8b2c44,
  abstract     = {The distribution of particles inside hadronic jets produced in the decay of boosted W and Z bosons can be used to discriminate such jets from the continuum background. Given that a jet has been identified as likely resulting from the hadronic decay of a boosted W or Z boson, this paper presents a technique for further differentiating Z bosons from W bosons. The variables used are jet mass, jet charge, and a b-tagging discriminant. A likelihood tagger is constructed from these variables and tested in the simulation of W′→ WZ for bosons in the transverse momentum range 200 GeV &lt; pT&lt; 400 GeV in s= 8 TeV pp collisions with the ATLAS detector at the LHC. For Z-boson tagging efficiencies of ϵZ= 90 , 50, and 10 % , one can achieve W+-boson tagging rejection factors (1 / ϵW+) of 1.7, 8.3 and 1000, respectively. It is not possible to measure these efficiencies in the data due to the lack of a pure sample of high pT, hadronically decaying Z bosons. However, the modelling of the tagger inputs for boosted W bosons is studied in data using a tt¯ -enriched sample of events in 20.3 fb- 1 of data at s= 8 TeV. The inputs are well modelled within uncertainties, which builds confidence in the expected tagger performance. © 2016, CERN for the benefit of the ATLAS collaboration.},
  author       = {Aad, G and Abbott, B. and Abdallah, J. and Abdinov, O and Aben, R and Abolins, M and Åkesson, Torsten and Bocchetta, Simona and Bryngemark, Lene and Doglioni, Caterina and Floderus, Anders and Hawkins, Anthony and Hedberg, Vincent and Ivarsson, Jenny and Jarlskog, Göran and Lytken, Else and Mjörnmark, Ulf and Smirnova, Oxana and Viazlo, Oleksandr and , },
  issn         = {1434-6044},
  language     = {eng},
  number       = {5},
  publisher    = {Springer},
  series       = {European Physical Journal C},
  title        = {A new method to distinguish hadronically decaying boosted Z bosons from W bosons using the ATLAS detector},
  url          = {http://dx.doi.org/10.1140/epjc/s10052-016-4065-1},
  volume       = {76},
  year         = {2016},
}