Measurements of top-quark pair spin correlations in the e mu channel at <mml:msqrt>s</mml:msqrt>=13 TeV using pp collisions in the ATLAS detector

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F20%3A73602323" target="_blank" >RIV/61989592:15310/20:73602323 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21220/20:00346699 RIV/68407700:21340/20:00346699 RIV/68407700:21670/20:00346699 RIV/00216208:11320/20:10423588

Výsledek na webu

<a href="https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-020-8181-6" target="_blank" >https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-020-8181-6</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1140/epjc/s10052-020-8181-6" target="_blank" >10.1140/epjc/s10052-020-8181-6</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Measurements of top-quark pair spin correlations in the e mu channel at <mml:msqrt>s</mml:msqrt>=13 TeV using pp collisions in the ATLAS detector

Popis výsledku v původním jazyce

A measurement of observables sensitive to spin correlations in tt&lt;overbar&gt;&lt;/mml:mover&gt; production is presented, using 36.1 fb-1 of pp collision data at &lt;mml:msqrt&gt;s&lt;/mml:msqrt&gt;=13 TeV recorded with the ATLAS detector at the Large Hadron Collider. Differential cross-sections are measured in events with exactly one electron and one muon with opposite-sign electric charge as a function of the azimuthal opening angle and the absolute difference in pseudorapidity between the electron and muon candidates in the laboratory frame. The azimuthal opening angle is also measured as a function of the invariant mass of the t&lt;mml:mover accent=&quot;true&quot;&gt;t&lt;mml:mo stretchy=&quot;false&quot;&gt;&lt;overbar&gt;&lt;/mml:mover&gt; system. The measured differential cross-sections are compared to predictions by several NLO Monte Carlo generators and fixed-order calculations. The observed degree of spin correlation is somewhat higher than predicted by the generators used. The data are consistent with the prediction of one of the fixed-order calculations at NLO, but agree less well with higher-order predictions. Using these leptonic observables, a search is performed for pair production of supersymmetric top squarks decaying into Standard Model top quarks and light neutralinos. Top squark masses between 170 and 230 GeV are largely excluded at the 95% confidence level for kinematically allowed values of the neutralino mass.

Název v anglickém jazyce

Measurements of top-quark pair spin correlations in the e mu channel at <mml:msqrt>s</mml:msqrt>=13 TeV using pp collisions in the ATLAS detector

Popis výsledku anglicky

A measurement of observables sensitive to spin correlations in tt&lt;overbar&gt;&lt;/mml:mover&gt; production is presented, using 36.1 fb-1 of pp collision data at &lt;mml:msqrt&gt;s&lt;/mml:msqrt&gt;=13 TeV recorded with the ATLAS detector at the Large Hadron Collider. Differential cross-sections are measured in events with exactly one electron and one muon with opposite-sign electric charge as a function of the azimuthal opening angle and the absolute difference in pseudorapidity between the electron and muon candidates in the laboratory frame. The azimuthal opening angle is also measured as a function of the invariant mass of the t&lt;mml:mover accent=&quot;true&quot;&gt;t&lt;mml:mo stretchy=&quot;false&quot;&gt;&lt;overbar&gt;&lt;/mml:mover&gt; system. The measured differential cross-sections are compared to predictions by several NLO Monte Carlo generators and fixed-order calculations. The observed degree of spin correlation is somewhat higher than predicted by the generators used. The data are consistent with the prediction of one of the fixed-order calculations at NLO, but agree less well with higher-order predictions. Using these leptonic observables, a search is performed for pair production of supersymmetric top squarks decaying into Standard Model top quarks and light neutralinos. Top squark masses between 170 and 230 GeV are largely excluded at the 95% confidence level for kinematically allowed values of the neutralino mass.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

EUROPEAN PHYSICAL JOURNAL C

ISSN

1434-6044

e-ISSN

—

Svazek periodika

80

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

43

Strana od-do

"754-1"-"754-43"

Kód UT WoS článku

000565271700001

EID výsledku v databázi Scopus

2-s2.0-85090083990