Search for t(t)over-bar H/A->t(t)over-bart(t)over-bar production in proton-proton collisions at root s=13 TeV with the ATLAS detector

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F25%3A00388987" target="_blank" >RIV/68407700:21220/25:00388987 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21240/25:00388987 RIV/68407700:21340/25:00388987 RIV/68407700:21670/25:00388987

Výsledek na webu

<a href="https://doi.org/10.1140/epjc/s10052-025-14041-z" target="_blank" >https://doi.org/10.1140/epjc/s10052-025-14041-z</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1140/epjc/s10052-025-14041-z" target="_blank" >10.1140/epjc/s10052-025-14041-z</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Search for t(t)over-bar H/A->t(t)over-bart(t)over-bar production in proton-proton collisions at root s=13 TeV with the ATLAS detector

Popis výsledku v původním jazyce

A search is presented for a heavy scalar (H) or pseudo-scalar (A) predicted by the two-Higgs-doublet models, where the H/A is produced in association with a top-quark pair (t (t) over barH/A), and with the H/A decaying into a t (t) over bar pair. The full LHC Run 2 proton-proton collision data collected by the ATLAS experiment is used, corresponding to an integrated luminosity of 139 fb(-1). Events are selected requiring exactly one or two opposite-charge electrons or muons. Data-driven corrections are applied to improve the modelling of the t (t) over bar +jets background in the regime with high jet and b-jet multiplicities. These include a novel multi-dimensional kinematic reweighting based on a neural network trained using data and simulations. An H/A-mass parameterised graph neural network is trained to optimise the signal-to-background discrimination. In combination with the previous search performed by the ATLAS Collaboration in the multilepton final state, the observed upper limits on the t (t) over barH/A -> t (t) over bart (t) over bar production cross-section at 95% confidence level range between 14 fb and 5.0 fb for an H/A with mass between 400 GeV and 1000 GeV, respectively. Assuming that both the H and A contribute to the t (t) over bart (t) over bar cross-section, tan beta values below 1.7 or 0.7 are excluded for a mass of 400 GeV or 1000 GeV, respectively. The results are also used to constrain a model predicting the pair production of a colour-octet scalar, with the scalar decaying into a t (t) over bar pair.

Název v anglickém jazyce

Search for t(t)over-bar H/A->t(t)over-bart(t)over-bar production in proton-proton collisions at root s=13 TeV with the ATLAS detector

Popis výsledku anglicky

A search is presented for a heavy scalar (H) or pseudo-scalar (A) predicted by the two-Higgs-doublet models, where the H/A is produced in association with a top-quark pair (t (t) over barH/A), and with the H/A decaying into a t (t) over bar pair. The full LHC Run 2 proton-proton collision data collected by the ATLAS experiment is used, corresponding to an integrated luminosity of 139 fb(-1). Events are selected requiring exactly one or two opposite-charge electrons or muons. Data-driven corrections are applied to improve the modelling of the t (t) over bar +jets background in the regime with high jet and b-jet multiplicities. These include a novel multi-dimensional kinematic reweighting based on a neural network trained using data and simulations. An H/A-mass parameterised graph neural network is trained to optimise the signal-to-background discrimination. In combination with the previous search performed by the ATLAS Collaboration in the multilepton final state, the observed upper limits on the t (t) over barH/A -> t (t) over bart (t) over bar production cross-section at 95% confidence level range between 14 fb and 5.0 fb for an H/A with mass between 400 GeV and 1000 GeV, respectively. Assuming that both the H and A contribute to the t (t) over bart (t) over bar cross-section, tan beta values below 1.7 or 0.7 are excluded for a mass of 400 GeV or 1000 GeV, respectively. The results are also used to constrain a model predicting the pair production of a colour-octet scalar, with the scalar decaying into a t (t) over bar pair.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

<a href="/cs/project/EH22_008%2F0004632" target="_blank" >EH22_008/0004632: Výzkum základních stavebních kamenů hmoty s využitím špičkových technologií</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

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

1434-6052

Svazek periodika

85

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

36

Strana od-do

—

Kód UT WoS článku

001595525400006

EID výsledku v databázi Scopus

2-s2.0-105009301920