The inclusive top quark pair ( $$t\bar{t}$$ ) cross-section $$\sigma _{t\bar{t}}$$ has been measured in proton–proton collisions at $$\sqrt{s}=13\,\text {TeV}$$ , using $$140\,{\text {fb}^{-1}} $$ of data collected by the ATLAS experiment at the Large Hadron Collider. Using events with an opposite-charge $$e\mu $$ pair and $\textit{b}$-tagged jets, the cross-section is measured to be: where the uncertainties reflect the limited size of the data sample, experimental and theoretical systematic effects, the integrated luminosity, and the proton beam energy, giving a total uncertainty of 1.3%. The result is used to determine the top quark pole mass via the dependence of the predicted cross-section on $${m_{t}^\textrm{pole}}$$ , giving $${m_{t}^\textrm{pole}}=172.8^{+1.5}_{-1.7}$$ $$\text {GeV}$$ . The same event sample is used to measure absolute and normalised differential cross-sections for the $$t\bar{t} \rightarrow e\mu \nu \bar{\nu }b\bar{b} $$ process as a function of single-lepton and dilepton kinematic variables. Complementary measurements of $$e\mu b\bar{b} $$ production, treating both $$t\bar{t}$$ and $\textit{Wt}$ events as signal, are also provided. Both sets of differential cross-sections are compared to the predictions of various Monte Carlo event generators, demonstrating that the state-of-the-art generators and $\textit{bb}$4$\textit{l}$ describe the data better than .

France

G. Aad

Norway

E. Aakvaag

United States

B. Abbott

United Arab Emirates

S. Abdelhameed

Germany

K. Abeling

N. Abicht

S. Abidi

M. Aboelela

Morocco

A. Aboulhorma

Israel

H. Abramowicz

Y. Abulaiti

Italy

United Kingdom

B. Acharya

A. Ackermann

C. Adam Bourdarios

Poland

L. Adamczyk

S. Addepalli

M. Addison

J. Adelman

Türkiye

A. Adiguzel

T. Adye

A. Affolder

Y. Afik

Spain

M. Agaras

A. Aggarwal

Romania

C. Agheorghiesei

Azerbaijan

F. Ahmadov

S. Ahuja

China

X. Ai

G. Aielli

A. Aikot

M. Tamlihat

B. Aitbenchikh

Sweden

T. Åkesson

A. Akimov

Japan

D. Akiyama

N. Akolkar

S. Aktas

G. Alberghi

Canada

J. Albert

Switzerland

U. Alberti

P. Albicocco

G. Albouy

S. Alderweireldt

Z. Alegria

M. Aleksa

I. Aleksandrov

C. Alexa

Greece

T. Alexopoulos

F. Alfonsi

M. Algren

M. Alhroob

Czechia

B. Ali

Saudi Arabia

H. Ali

S. Ali

S. Alibocus

South Africa

M. Aliev

G. Alimonti

W. Alkakhi

C. Allaire

B. Allbrooke

D. Allen

J. Allen

P. Allport

A. Aloisio

Argentina

F. Alonso

C. Alpigiani

Z. Alsolami

A. Alvarez Fernandez

M. Alves Cardoso

M. Alviggi

M. Aly

Brazil

Y. Amaral Coutinho

A. Ambler

C. Amelung

M. Amerl

C. Ames

T. Amezza

D. Amidei

B. Amini

K. Amirie

A. Amirkhanov

Portugal

S. Amor Dos Santos

K. Amos

D. Amperiadou

S. An

C. Anastopoulos

T. Andeen

J. Anders

A. Anderson

A. Andreazza

S. Angelidakis

A. Angerami

A. Anisenkov

A. Annovi

C. Antel

E. Antipov

M. Antonelli

F. Anulli

Precise measurement of the $$t\bar{t}$$ production cross-section and lepton differential distributions in $$ e\mu $$ dilepton events from $$\sqrt{s}=13\,\text {TeV}$$ $\textit{pp}$ collisions with the ATLAS detector

<p>In the present work, I explore the production of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo>¯</mo></mover><mn>0</mn></msup></mrow></math> using <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></mrow></math> collision data at ten center-of-mass energies between 3.51 and 4.95 GeV collected with the BESIII detector at the BEPCII collider and corresponding to an integrated luminosity of 30 <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mrow><mi>fb</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> to study the structure of baryons. The data collected by the BESIII detector are useful for the study of XYZ states, and this collaboration continues the exploration of these exotic charmoniumlike states. At higher center-of-mass energies the baryon-antibaryon pair production in electron-positron annihilation provides a powerful tool. In this paper, I investigate a hyperon pair produced in the electron-positron annihilation reactions, and I present the phenomenological results for the process using the BESIII detector at the BEPCII collider. In the reaction <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo>→</mo><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo>¯</mo></mover><mn>0</mn></msup></mrow></math>, I consider two different contributions: one from the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>D</mi></math>-meson loop and the other from the three-gluon charmonium annihilation. In this process I calculate the total cross section including the contributions of the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>D</mi></math>-meson loop and three-gluon loops as well as the interference of all diagrams. In the case of a purely electromagnetic mechanism for these contributions, large relative phases are generated. For a large momentum transferred region I get as a byproduct a fit of the electromagnetic form factor of the <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup></math> hyperon. In the present work, in addition to the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ψ</mi><mo>(</mo><mn>3770</mn><mo>)</mo></mrow></math> charmonium, I also take into account the contributions of other charmonium (-like) states, such as <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ψ</mi><mo>(</mo><mn>4040</mn><mo>)</mo></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ψ</mi><mo>(</mo><mn>4160</mn><mo>)</mo></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Y</mi><mo>(</mo><mn>4230</mn><mo>)</mo></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Y</mi><mo>(</mo><mn>4360</mn><mo>)</mo></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ψ</mi><mo>(</mo><mn>4415</mn><mo>)</mo></mrow></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Y</mi><mo>(</mo><mn>4660</mn><mo>)</mo></mrow></math>. On the whole my results are in good agreement with the available experimental data.</p>

JINR

Azad I. Ahmadov

Cross section of the process <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>e</mi><mo>+</mo></msup><mo>+</mo><msup><mi>e</mi><mo>−</mo></msup><mo>→</mo><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mo>+</mo><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo>¯</mo></mover><mn>0</mn></msup></mrow></math> in the vicinity of charmonium <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ψ</mi><mo>(</mo><mn>3770</mn><mo>)</mo></mrow></math> and in the charmonium (-like) state including the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>D</mi></math>-meson loop and three-gluon contributions

<p>Using <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> collision data collected with the BESIII detector corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>44.2</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, we measure the Born cross sections for the process <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mi mathvariant="normal">Ξ</mi><mo stretchy="false">(</mo><mn>1530</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo stretchy="false">¯</mo></mover><mn>0</mn></msup><mo>+</mo><mi mathvariant="normal">c</mi><mo>.</mo><mi mathvariant="normal">c</mi><mo>.</mo></math> at 48 center-of-mass energies between 3.51 and 4.95 GeV. The potential signal from non-<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover></math> decays for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ψ</mi><mo stretchy="false">(</mo><mn>3770</mn><mo stretchy="false">)</mo></math>, i.e., <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>ψ</mi><mo stretchy="false">(</mo><mn>3770</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><mi mathvariant="normal">Ξ</mi><mo stretchy="false">(</mo><mn>1530</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo stretchy="false">¯</mo></mover><mn>0</mn></msup><mo>+</mo><mi>c</mi><mo>.</mo><mi>c</mi></mrow></math>., is investigated by fitting the dressed cross section, no obvious signal is found. The upper limit of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">B</mi><mo stretchy="false">(</mo><mi>ψ</mi><mo stretchy="false">(</mo><mn>3770</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><mi mathvariant="normal">Ξ</mi><mo stretchy="false">(</mo><mn>1530</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo stretchy="false">¯</mo></mover><mn>0</mn></msup></math>) at 90% confidence level is given.</p>

M. Ablikim

Russia

M.N. Achasov

P. Adlarson

X.C. Ai

R. Aliberti

A. Amoroso

Q. An

Y. Bai

O. Bakina

Y. Ban

H.R. Bao

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M.B. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

R.A. Briere

A. Brueggemann

H. Cai

M.H. Cai

X. Cai

A. Calcaterra

G.F. Cao

N. Cao

S.A. Cetin

X.Y. Chai

J.F. Chang

T.T. Chang

G.R. Che

Y.Z. Che

C.H. Chen

Chao Chen

G. Chen

H.S. Chen

H.Y. Chen

M.L. Chen

S.J. Chen

S.M. Chen

T. Chen

X.R. Chen

X.T. Chen

X.Y. Chen

Y.B. Chen

Y.Q. Chen

Z.K. Chen

J.C. Cheng

L.N. Cheng

South Korea

S.K. Choi

X. Chu

G. Cibinetto

F. Cossio

J. Cottee-Meldrum

H.L. Dai

J.P. Dai

X.C. Dai

A. Dbeyssi

R.E. de Boer

D. Dedovich

C.Q. Deng

Z.Y. Deng

A. Denig

I. Denisenko

Cross sections measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mi mathvariant="normal">Ξ</mi><mo stretchy="false">(</mo><mn>1530</mn><msup><mo stretchy="false">)</mo><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo stretchy="false">¯</mo></mover><mn>0</mn></msup><mo>+</mo><mi mathvariant="normal">c</mi><mo>.</mo><mi mathvariant="normal">c</mi><mo>.</mo></math> and search for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>ψ</mi><mo stretchy="false">(</mo><mn>3770</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><mi mathvariant="normal">Ξ</mi><mo stretchy="false">(</mo><mn>1530</mn><msup><mrow><mo stretchy="false">)</mo></mrow><mrow><mn>0</mn></mrow></msup><msup><mrow><mover accent="true"><mrow><mi mathvariant="normal">Ξ</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mn>0</mn></mrow></msup><mo>+</mo><mi mathvariant="normal">c</mi><mo>.</mo><mi mathvariant="normal">c</mi><mo>.</mo></mrow></math>