Search for production of four top quarks in final states with same-sign or multiple leptons in proton-proton collisions at √s=13 TeV

Bibliographic Details
Parent link:European Physical Journal C
Vol. 80, iss. 2.— 2020.— [75, 31 p.]
Corporate Author: Национальный исследовательский Томский политехнический университет Исследовательская школа физики высокоэнергетических процессов
Other Authors: Sirunyan A. M., Tumasyan A. R., Adam W. Wolfgang, Ambrogi F. Federico, Tyurin N. E. Nikolay Evgenjevich, Babaev A. A. Anton Anatoljevich
Summary:Title screen
The standard model (SM) production of four top quarks (tt¯tt¯) in proton-proton collisions is studied by the CMS Collaboration. The data sample, collected during the 2016-2018 data taking of the LHC, corresponds to an integrated luminosity of 137fb−1 at a center-of-mass energy of 13TeV. The events are required to contain two same-sign charged leptons (electrons or muons) or at least three leptons, and jets. The observed and expected significances for the tt¯tt¯ signal are respectively 2.6 and 2.7 standard deviations, and the tt¯tt¯ cross section is measured to be 12.6+5.8−5.2fb. The results are used to constrain the Yukawa coupling of the top quark to the Higgs boson, yt, yielding a limit of |yt/ySMt|<1.7|yt/ytSM|<1.7 at 95% confidence level, where ySMt is the SM value of yt. They are also used to constrain the oblique parameter of the Higgs boson in an effective field theory framework, H^<0.12H^<0.12. Limits are set on the production of a heavy scalar or pseudoscalar boson in Type-II two-Higgs-doublet and simplified dark matter models, with exclusion limits reaching 350-470GeV and 350-550GeV for scalar and pseudoscalar bosons, respectively. Upper bounds are also set on couplings of the top quark to new light particles.
Режим доступа: по договору с организацией-держателем ресурса
Published: 2020
Subjects:
Online Access:https://doi.org/10.1140/epjc/s10052-019-7593-7
Format: Electronic Book Chapter
KOHA link:https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=666360