We suggest a dynamical mechanism which explains why, in the supersymmetric Ishibashi-Kawai-Kitazawa-Tsuchiya matrix model, the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>9</mn><mo stretchy="false">)</mo></math> symmetry of the Lagrangian is spontaneously broken to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo><mo>×</mo><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>6</mn><mo stretchy="false">)</mo></math>, allowing only three large classical spatial dimensions to emerge. The argument relies on the identification of D-strings as stable excitations of the matrices about the cosmological background and the absence of forces between parallel D-string excitations. A spatial dimension can only become large if the D-strings winding in that direction can annihilate. In the absence of forces, this requires the string-world sheets to intersect, a process which is highly suppressed if more than three dimensions of space are large. Implications for a recently proposed matrix cosmology scenario are discussed.

Canada

Robert Brandenberger

Julia Pasiecznik

Origin of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>9</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo><mo>×</mo><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>6</mn><mo stretchy="false">)</mo></math> symmetry breaking in the type IIB matrix model

High precision single-differential $$W^\pm $$ -boson production cross-sections as a function of electron or muon transverse momentum $$p_\textrm{T}$$ or their pseudorapity $$\eta $$ , as well as double-differential cross-sections as functions of these variables, are measured in proton–proton collisions at centre-of-mass energies $$\sqrt{s}=5.02$$ TeV and 13 TeV. The $\textit{W}$-boson charge asymmetry as a function of lepton $$\eta $$ is also measured. The data, collected in dedicated runs at reduced instantaneous luminosity with the ATLAS detector at the Large Hadron Collider, correspond to integrated luminosities of 255 pb $$^{-1}$$ at 5.02 TeV and 338 pb $$^{-1}$$ at 13 TeV. The measurements are in agreement with Standard-Model predictions calculated at next-to-next-to-leading-order in the strong coupling constant $$\alpha _s$$ including transverse-momentum resummation at next-to-next-to-leading logarithmic accuracy using several parton distribution functions. The impact of the measured differential cross-sections as a function of lepton $$\eta $$ on the determination of these functions is studied using a profiling technique.

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. 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. Ait Tamlihat

B. Aitbenchikh

M. Akbiyik

Sweden

T. Åkesson

A. Akimov

Japan

D. Akiyama

N. Akolkar

S. Aktas

G. Alberghi

J. Albert

P. Albicocco

G. Albouy

S. Alderweireldt

Z. Alegria

Switzerland

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

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

D. Amidei

B. Amini

K. Amirie

A. Amirkhanov

Portugal

S. Amor Dos Santos

K. Amos

D. Amperiadou

S. An

V. Ananiev

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

M. Aoki

T. Aoki

Measurement of $$W^{\pm }$$ -boson differential cross-sections in proton–proton collisions with low pile-up data at $$\sqrt{s} = 5.02$$ TeV and $$13\,\hbox {TeV}$$ with the ATLAS detector

We compute a complete set of the two-loop Feynman integrals that are required for the next-to-next-to-leading order QCD corrections to on-shell top-pair production in association with a $\textit{W}$ boson at hadron colliders in the leading colour approximation. These Feynman integrals also contribute to Higgs or $\textit{Z}$-boson production in association with a top pair. We employ the method of differential equations (DEs), facilitated by the use of finite field methods to handle the algebraic complexity stemming from the seven-scale kinematics. The presence of the top quark in the virtual propagators, in addition to the mass of the external $\textit{W}$ boson, gives rise to nested square roots and three elliptic curves. We obtain DEs that depend at most quadratically on the dimensional regulator $\textit{ϵ}$ for sectors where these analytic structures appear, and are $\textit{ϵ}$-factorised otherwise. We express the DEs in terms of a minimal set of differential one-forms, separating the logarithmic ones. We solve the DEs numerically in the physical kinematic region, with the method of generalised power series expansions.

Matteo Becchetti

Dhimiter Canko

Vsevolod Chestnov

Tiziano Peraro

Mattia Pozzoli

Simone Zoia

Two-loop Feynman integrals for leading colour $$ t\overline{t}W $$ production at hadron colliders

We consider a bulk plus boundary extension of Jackiw-Teitelboim gravity coupled with non-Abelian gauge fields. The generalization is performed in the Poisson sigma model formulation and it is derived as a dimensional reduction of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>AdS</mi><mn>3</mn></msub></math> Chern-Simons theory with Wess-Zumino-Witten (WZW) boundary terms. We discuss the role of boundary conditions in relation to the symmetries of the boundary dynamics and we show that the boundary action can be written in terms of coadjoint orbits of an appropriate Virasoro-Kac-Moody group. We obtain a Schwarzian action and interaction terms with additional edge modes that match the effective low-energy action of recent Sachdev–Ye–Kitaev-like tensor models.

Goffredo Chirco

Lucio Vacchiano

Patrizia Vitale

<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="fraktur">s</mi><mi mathvariant="fraktur">o</mi></mrow><mo stretchy="false">(</mo><mn>2</mn><mo>,</mo><mn>2</mn><mo stretchy="false">)</mo></math> extension of Jackiw-Teitelboim gravity via the Virasoro-Kac-Moody semidirect product

We discuss prompt production of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>J</mi><mo>/</mo><mi>ψ</mi></math> mesons in proton-proton collisions at the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mrow><mn>68.5</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></mrow></math> energy within the nonrelativistic quantum chromodynamics <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>k</mi><mi>t</mi></msub></math>-factorization approach using different unintegrated gluon distribution functions (UGDFs). We include both direct color-singlet production (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mi>g</mi><mo stretchy="false">→</mo><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>g</mi></math>) as well as a feed-down from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>χ</mi><mi>c</mi></msub><mo stretchy="false">→</mo><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>γ</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>ψ</mi><mo>′</mo></msup><mo stretchy="false">→</mo><mi>J</mi><mo>/</mo><mi>ψ</mi><mi>X</mi></math> decays. The production of the decaying mesons <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>χ</mi><mi>c</mi></msub></math> or <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>ψ</mi><mo>′</mo></msup></math> is also calculated within the nonrelativistic quantum chromodynamics <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>k</mi><mi>t</mi></msub></math>-factorization approach. Differential distributions in the rapidity and transverse momentum of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>J</mi><mo>/</mo><mi>ψ</mi></math> are calculated and compared with experimental data of LHCb collaboration. The LHCb fixed target data allow us to test UGDFs in a new range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>x</mi></math>.

Anna Cisek

Antoni Szczurek

Prompt inclusive production of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>J</mi><mo>/</mo><mi>ψ</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>ψ</mi><mo>′</mo></msup></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>χ</mi><mi>c</mi></msub></math> mesons at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>68.5</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> energy within the NRQCD <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>k</mi><mi>t</mi></msub></math>-factorization approach

We perform a model-independent measurement of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>D</mi></mrow><mrow><mn>0</mn></mrow></msup><mtext>−</mtext><msup><mrow><mover accent="true"><mrow><mi>D</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mn>0</mn></mrow></msup></mrow></math> mixing parameters using samples 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></math> -collision data collected by the Belle and Belle II experiments that have integrated luminosities of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>951</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>408</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>, respectively. Approximately <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2.05</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></math> neutral <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi></math> mesons are reconstructed in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msubsup><mi>K</mi><mi mathvariant="normal">S</mi><mn>0</mn></msubsup><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup></math> channel, with the neutral <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi></math> flavor tagged by the charge of the pion in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mrow><mo>*</mo><mo>+</mo></mrow></msup><mo stretchy="false">→</mo><msup><mi>D</mi><mn>0</mn></msup><msup><mi>π</mi><mo>+</mo></msup></math> decay. Assuming charge-parity symmetry, the mixing parameters are measured to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>x</mi><mo>=</mo><mo stretchy="false">(</mo><mn>4.0</mn><mo>±</mo><mn>1.7</mn><mo>±</mo><mn>0.4</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>y</mi><mo>=</mo><mo stretchy="false">(</mo><mn>2.9</mn><mo>±</mo><mn>1.4</mn><mo>±</mo><mn>0.3</mn><mo stretchy="false">)</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>3</mn></mrow></msup></math>, where the first uncertainties are statistical and the second systematic. The results are consistent with previous determinations.

I. Adachi

L. Aggarwal

H. Ahmed

H. Aihara

N. Akopov

N. Althubiti

N. Anh Ky

D.M. Asner

H. Atmacan

V. Aushev

M. Aversano

R. Ayad

N.K. Baghel

P. Bambade

Sw. Banerjee

S. Bansal

M. Barrett

M. Bartl

J. Baudot

A. Beaubien

J. Becker

J.V. Bennett

V. Bertacchi

M. Bertemes

E. Bertholet

M. Bessner

S. Bettarini

B. Bhuyan

D. Biswas

D. Bodrov

A. Bolz

A. Bondar

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

R.A. Briere

T.E. Browder

A. Budano

S. Bussino

Q. Campagna

M. Campajola

G. Casarosa

C. Cecchi

P. Chang

R. Cheaib

P. Cheema

B.G. Cheon

K. Chilikin

K. Chirapatpimol

H.E. Cho

K. Cho

Model-independent measurement of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mtext>−</mtext><msup><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mn>0</mn></msup></math> mixing parameters in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>D</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>π</mi><mo>+</mo></msup><msup><mi>π</mi><mo>−</mo></msup></math> decays at Belle and Belle II