Search for new phenomena in tt¯ events with large missing transverse momentum in proton-proton collisions at s√=7 TeV with the ATLAS detector

Barton, Adam and Borissov, Guennadi and Bouhova-Thacker, Eva and Brodbeck, Timothy and Catmore, James and Chilingarov, Alexandre and Davidson, Ruth and de Mora, Lee and Fox, Harald and Henderson, Robert and Hughes, Gareth and Jones, Roger William Lewis and Kartvelishvili, Vakhtang and Long, Robin and Love, Peter and Ratoff, Peter and Smizanska, Maria and Walder, James (2012) Search for new phenomena in tt¯ events with large missing transverse momentum in proton-proton collisions at s√=7  TeV with the ATLAS detector. Physical review letters, 108 (4). ISSN 1079-7114

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Abstract

A search for new phenomena in tt¯ events with large missing transverse momentum in proton-proton collisions at a center-of-mass energy of 7 TeV is presented. The measurement is based on 1.04  fb−1 of data collected with the ATLAS detector at the LHC. Contributions to this final state may arise from a number of standard model extensions. The results are interpreted in terms of a model where new top-quark partners are pair produced and each decay to an on-shell top (or antitop) quark and a long-lived undetected neutral particle. The data are found to be consistent with standard model expectations. A limit at 95% confidence level is set excluding a cross section times branching ratio of 1.1 pb for a top-partner mass of 420 GeV and a neutral particle mass less than 10 GeV. In a model of exotic fourth generation quarks, top-partner masses are excluded up to 420 GeV and neutral particle masses up to 140 GeV.

Item Type:
Journal Article
Journal or Publication Title:
Physical review letters
Additional Information:
Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. © 2012 CERN, for the ATLAS Collaboration
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3100
Subjects:
ID Code:
68230
Deposited By:
Deposited On:
04 Jan 2014 00:05
Refereed?:
Yes
Published?:
Published
Last Modified:
01 Apr 2020 03:30