Measurements of top quark spin observables in tt events using dilepton final states in root s=8 TeV pp collisions with the ATLAS detector

M. Aaboud, G. Aad, B. Abbott, J. Abdallah, O. Abdinov, B Abeloos, O.S. AbouZeid, NL Abraham, H. Abramowicz, H. Abreu, R. Abreu, Y. Abulaiti, B.S. Acharya, Shin-ichi Adachi, L. Adamczyk, David L. Adams, J P Adelman, S. Adomeit, A. A. Affolder, Mogens DamJørn Dines Hansen, Jørgen Beck Hansen, Stefania Xella, Peter Henrik Hansen, Troels Christian Petersen, Ask Emil Løvschall-Jensen, Alejandro Alonso Diaz, James William Monk, Lars Egholm Pedersen, Graig Wiglesworth, Gorm Aske Gram Krohn Galster, Simon Holm Stark, Geert-Jan Besjes, Fabian Alexander Jürgen Thiele, Flavia de Almeida Dias, Milena Bajic

12 Citationer (Scopus)
36 Downloads (Pure)

Abstract

Measurements of top quark spin observables in tt¯ events are presented based on 20.2 fb−1 of s=8 TeV proton-proton collisions recorded with the ATLAS detector at the LHC. The analysis is performed in the dilepton final state, characterised by the presence of two isolated leptons (electrons or muons). There are 15 observables, each sensitive to a different coefficient of the spin density matrix of tt¯ production, which are measured independently. Ten of these observables are measured for the first time. All of them are corrected for detector resolution and acceptance effects back to the parton and stable-particle levels. The measured values of the observables at parton level are compared to Standard Model predictions at next-to-leading order in QCD. The corrected distributions at stable-particle level are presented and the means of the distributions are compared to Monte Carlo predictions. No significant deviation from the Standard Model is observed for any observable.[Figure not available: see fulltext.]

OriginalsprogEngelsk
Artikelnummer113
TidsskriftJournal of High Energy Physics
Vol/bind2017
Udgave nummer3
ISSN1126-6708
DOI
StatusUdgivet - 1 mar. 2017

Fingeraftryk

Dyk ned i forskningsemnerne om 'Measurements of top quark spin observables in tt events using dilepton final states in root s=8 TeV pp collisions with the ATLAS detector'. Sammen danner de et unikt fingeraftryk.

Citationsformater