Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Search for a scalar partner of the top quark in the all-hadronic tt¯ plus missing transverse momentum final state at √s=13 TeV with the ATLAS detector

Aad, G ; Åkesson, Torsten LU orcid ; Bocchetta, Simona LU ; Corrigan, Eric Edward LU ; Doglioni, Caterina LU ; Geisen, Jannik LU orcid ; Gregersen, Kristian LU ; Brottmann Hansen, Eva LU ; Hedberg, Vincent LU and Jarlskog, Göran LU , et al. (2020) In European Physical Journal C 80(8).
Abstract
A search for direct pair production of scalar partners of the top quark (top squarks or scalar third-generation up-type leptoquarks) in the all-hadronic tt¯ plus missing transverse momentum final state is presented. The analysis of 139 fb - 1 of s=13 TeV proton–proton collision data collected using the ATLAS detector at the LHC yields no significant excess over the Standard Model background expectation. To interpret the results, a supersymmetric model is used where the top squark decays via t~→t(∗)χ~10, with t(∗) denoting an on-shell (off-shell) top quark and χ~10 the lightest neutralino. Three specific event selections are optimised for the following scenarios. In the scenario where mt~>mt+mχ~10, top squark masses are excluded in the... (More)
A search for direct pair production of scalar partners of the top quark (top squarks or scalar third-generation up-type leptoquarks) in the all-hadronic tt¯ plus missing transverse momentum final state is presented. The analysis of 139 fb - 1 of s=13 TeV proton–proton collision data collected using the ATLAS detector at the LHC yields no significant excess over the Standard Model background expectation. To interpret the results, a supersymmetric model is used where the top squark decays via t~→t(∗)χ~10, with t(∗) denoting an on-shell (off-shell) top quark and χ~10 the lightest neutralino. Three specific event selections are optimised for the following scenarios. In the scenario where mt~>mt+mχ~10, top squark masses are excluded in the range 400–1250 GeV for χ~10 masses below 200 GeV at 95% confidence level. In the situation where mt~∼mt+mχ~10, top squark masses in the range 300–630 GeV are excluded, while in the case where mt~<mW+mb+mχ~10 (with mt~-mχ~10≥5 GeV), considered for the first time in an ATLAS all-hadronic search, top squark masses in the range 300–660 GeV are excluded. Limits are also set for scalar third-generation up-type leptoquarks, excluding leptoquarks with masses below 1240 GeV when considering only leptoquark decays into a top quark and a neutrino. © 2020, CERN for the benefit of the ATLAS collaboration. (Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; ; ; and , et al. (More)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; and (Less)
author collaboration
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
European Physical Journal C
volume
80
issue
8
article number
737
publisher
Springer
external identifiers
  • scopus:85090049230
ISSN
1434-6044
DOI
10.1140/epjc/s10052-020-8102-8
language
English
LU publication?
yes
id
dd6b70a5-75dc-4325-9678-f050eaf214b0
date added to LUP
2020-09-28 09:57:46
date last changed
2023-04-10 20:36:12
@article{dd6b70a5-75dc-4325-9678-f050eaf214b0,
  abstract     = {{A search for direct pair production of scalar partners of the top quark (top squarks or scalar third-generation up-type leptoquarks) in the all-hadronic tt¯ plus missing transverse momentum final state is presented. The analysis of 139 fb - 1 of s=13 TeV proton–proton collision data collected using the ATLAS detector at the LHC yields no significant excess over the Standard Model background expectation. To interpret the results, a supersymmetric model is used where the top squark decays via t~→t(∗)χ~10, with t(∗) denoting an on-shell (off-shell) top quark and χ~10 the lightest neutralino. Three specific event selections are optimised for the following scenarios. In the scenario where mt~&gt;mt+mχ~10, top squark masses are excluded in the range 400–1250 GeV for χ~10 masses below 200 GeV at 95% confidence level. In the situation where mt~∼mt+mχ~10, top squark masses in the range 300–630 GeV are excluded, while in the case where mt~&lt;mW+mb+mχ~10 (with mt~-mχ~10≥5 GeV), considered for the first time in an ATLAS all-hadronic search, top squark masses in the range 300–660 GeV are excluded. Limits are also set for scalar third-generation up-type leptoquarks, excluding leptoquarks with masses below 1240 GeV when considering only leptoquark decays into a top quark and a neutrino. © 2020, CERN for the benefit of the ATLAS collaboration.}},
  author       = {{Aad, G and Åkesson, Torsten and Bocchetta, Simona and Corrigan, Eric Edward and Doglioni, Caterina and Geisen, Jannik and Gregersen, Kristian and Brottmann Hansen, Eva and Hedberg, Vincent and Jarlskog, Göran and Kellermann, Edgar and Konya, Balazs and Lytken, Else and Mankinen, Katja and Marcon, Caterina and Mjörnmark, Ulf and Mullier, Geoffrey André Adrien and Pöttgen, Ruth and Poulsen, Trine and Skorda, Eleni and Smirnova, Oxana and Zwalinski, L.}},
  issn         = {{1434-6044}},
  language     = {{eng}},
  number       = {{8}},
  publisher    = {{Springer}},
  series       = {{European Physical Journal C}},
  title        = {{Search for a scalar partner of the top quark in the all-hadronic tt¯ plus missing transverse momentum final state at √s=13 TeV with the ATLAS detector}},
  url          = {{http://dx.doi.org/10.1140/epjc/s10052-020-8102-8}},
  doi          = {{10.1140/epjc/s10052-020-8102-8}},
  volume       = {{80}},
  year         = {{2020}},
}