The first measurements of the top- and antitop-quark differential production cross sections and the top-quark charge asymmetry in the forward region are presented, using proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>5.4</mn><mtext> </mtext><mtext> </mtext><msup><mrow><mi>fb</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math>. The total production cross sections of top and antitop quarks are also determined. Measurements are performed using the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>μ</mi><mo>+</mo><mrow><mi>b</mi><mtext>-jet</mtext></mrow></mrow></math> final state within a fiducial region defined by <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>b</mi></mrow></math>-jet <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi mathvariant="normal">T</mi><mo>,</mo><mtext>jet</mtext></mrow></msub><mo>&gt;</mo><mn>50</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></mrow></math> and pseudorapidity <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>2.2</mn><mo>&lt;</mo><msub><mrow><mi>η</mi></mrow><mrow><mtext>jet</mtext></mrow></msub><mo>&lt;</mo><mn>4.0</mn></mrow></math>, with the muon from the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi></math>-boson decay required to have <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi mathvariant="normal">T</mi><mo>,</mo><mi>μ</mi></mrow></msub><mo>&gt;</mo><mn>25</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2.0</mn><mo>&lt;</mo><msub><mi>η</mi><mi>μ</mi></msub><mo>&lt;</mo><mn>4.5</mn></math>. The muon and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>b</mi></mrow></math>-jet system must satisfy <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>p</mi></mrow><mrow><mi mathvariant="normal">T</mi></mrow></msub><mo stretchy="false">(</mo><mi>μ</mi><mo>+</mo><mtext>jet</mtext><mo stretchy="false">)</mo><mo>&gt;</mo><mn>20</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></mrow></math>. The measured integrated production cross sections for the top and antitop quarks are <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>σ</mi></mrow><mrow><mi>t</mi></mrow></msub><mo>=</mo><mn>0.95</mn><mo>±</mo><mn>0.04</mn><mo>±</mo><mn>0.08</mn><mo>±</mo><mn>0.02</mn><mtext> </mtext><mtext> </mtext><mi>pb</mi></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>σ</mi></mrow><mrow><mover accent="true"><mrow><mi>t</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow></msub><mo>=</mo><mn>0.81</mn><mo>±</mo><mn>0.03</mn><mo>±</mo><mn>0.07</mn><mo>±</mo><mn>0.02</mn><mtext> </mtext><mtext> </mtext><mi>pb</mi></mrow></math>, where the first uncertainty is statistical, the second systematic, and the third accounts for the luminosity uncertainty. The top-quark charge asymmetry is measured to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi>A</mi></mrow><mrow><mi>C</mi></mrow><mrow><mi>t</mi></mrow></msubsup><mo>=</mo><mn>0.08</mn><mo>±</mo><mn>0.03</mn><mo>±</mo><mn>0.01</mn></mrow></math>, where the first uncertainty is statistical and the second is systematic. These results are consistent with next-to-leading order Standard Model predictions.

Netherlands

R. Aaij

United Kingdom

A.S.W. Abdelmotteleb

Switzerland

C. Abellan Beteta

F. Abudinén

T. Ackernley

United States

A.A. Adefisoye

Spain

B. Adeva

M. Adinolfi

P. Adlarson

France

C. Agapopoulou

C.A. Aidala

Z. Ajaltouni

S. Akar

K. Akiba

Poland

M. Akthar

Italy

P. Albicocco

Germany

J. Albrecht

R. Aleksiejunas

CERN

F. Alessio

P. Alvarez Cartelle

R. Amalric

Brazil

S. Amato

J.L. Amey

Y. Amhis

China

L. An

L. Anderlini

M. Andersson

P. Andreola

M. Andreotti

S. Andres Estrada

A. Anelli

D. Ao

C. Arata

F. Archilli

Z. Areg

M. Argenton

Costa Rica

S. Arguedas Cuendis

L. Arnone

A. Artamonov

M. Artuso

E. Aslanides

R. Ataíde Da Silva

M. Atzeni

B. Audurier

J.A. Authier

D. Bacher

I. Bachiller Perea

S. Bachmann

M. Bachmayer

J.J. Back

P. Baladron Rodriguez

V. Balagura

A. Balboni

W. Baldini

Z. Baldwin

L. Balzani

H. Bao

J. Baptista de Souza Leite

C. Barbero Pretel

M. Barbetti

I.R. Barbosa

R.J. Barlow

M. Barnyakov

S. Barsuk

W. Barter

J. Bartz

S. Bashir

B. Batsukh

P.B. Battista

A. Bavarchee

A. Bay

A. Beck

M. Becker

F. Bedeschi

I.B. Bediaga

N.A. Behling

S. Belin

A. Bellavista

K. Belous

I. Belov

I. Belyaev

G. Benane

G. Bencivenni

E. Ben-Haim

A. Berezhnoy

R. Bernet

S. Bernet Andres

A. Bertolin

F. Betti

J. Bex

O. Bezshyyko

S. Bhattacharya

M.S. Bieker

N.V. Biesuz

A. Biolchini

M. Birch

F.C.R. Bishop

A. Bitadze

A. Bizzeti

T. Blake

Measurement of the Top-Quark Production Cross Section and Charge Asymmetry at LHCb

The Coherent Neutrino-Nucleus Interaction Experiment (CONNIE) aims to detect the coherent scattering (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math>) of reactor antineutrinos off silicon nuclei using thick fully depleted high-resistivity silicon CCDs. Two Skipper-CCD sensors with subelectron readout noise capability were installed at the experiment next to the Angra-2 reactor in 2021, making CONNIE the first experiment to employ Skipper-CCDs for reactor neutrino detection. We report on the performance of the Skipper-CCDs, the new data processing, data quality, and event selection for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math> interactions, which enable CONNIE to reach a record low detection threshold of 15 eV. The data were collected over 300 days in 2021–2022 and correspond to exposures of 14.9 g-days with the reactor-on and 3.5 g-days with the reactor-off. The difference between the reactor-on and off event rates shows no excess and yields upper limits for the neutrino interaction rates, comparable with previous CONNIE limits from standard CCDs and higher exposures. Searches for new neutrino interactions beyond the Standard Model improve the previous CONNIE limit on a simplified model with light vector mediators. A first dark matter (DM) search by diurnal modulation by CONNIE obtains the best limits on the DM-electron scattering cross section by a surface-level experiment. These promising results, obtained using a very small-mass sensor, illustrate the potential of Skipper-CCDs to probe rare neutrino interactions and motivate the plans to increase the detector mass in the near future.

Mexico

Alexis A. Aguilar-Arevalo

Juan Carlos D’Olivo

Y. Sarkis

Argentina

Nicolas Avalos

Xavier Bertou

Carla Bonifazi

Gustavo Cancelo

Juan Estrada

Richard Ford

Kevin Kuk

Andrew Lathrop

Javier Tiffenberg

Sho Uemura

Brenda A. Cervantes-Vergara

Paraguay

Claudio Chavez

Fernando Chierchie

Gustavo Coelho Corrêa

João dos Anjos

Herman P. Lima

Guillermo Fernandez Moroni

Aldo R. Fernandes Neto

Ben Kilminster

Patrick Lemos

Katherine Maslova

Irina Nasteva

Ana Carolina Oliveira

Pedro Ventura

Martin Makler

Franciole Marinho

Jorge Molina

Diego Stalder

Laura Paulucci

Dario Rodrigues

Miguel Sofo Haro

Searches for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>CE</mi><mi>ν</mi><mi>NS</mi></mrow></math> and physics beyond the standard model using Skipper-CCDs at CONNIE

We consider planar $$ \mathcal{N} $$ = 4 super Yang-Mills at finite temperature with chemical potentials that couple either to the $\textit{R}$-charges or the spins of the operators. We find expressions for the Hagedorn temperatures at both zero coupling by explicitly counting states, and at strong coupling using the string theory dual. We then apply the quantum spectral curve (QSC) to this problem, which adds additional twists to the $\textit{Q}$-functions. For a single chemical potential $\textit{μ}$ coupled to one of the $\textit{R}$-charges, we find the analytic weak-coupling Hagedorn temperature to one-loop order for any value of $\textit{μ}$, and to two-loop order for $\textit{μ}$ = 1/2. We then solve the QSC numerically, showing that at strong coupling there is good agreement with the string theory prediction to order 1/$\textit{λ}$ . This provides further evidence for a recent conjecture of Harmark for the form of the world-sheet zero-point shift. We also use the QSC to find the analytic one-loop correction to the Hagedorn temperature with non-zero chemical potentials coupled to the spins.

Sweden

Simon Ekhammar

Joseph Minahan

Charles Thull

Twisting the Hagedorn temperature in planar $$ \mathcal{N} $$ = 4 super Yang-Mills

An amplitude analysis of the $${{{B} ^0} \!\rightarrow {\eta _{c}} (1S) {{K} ^+} {{\pi } ^-}} $$ decays with $${\eta _{c}} (1S) \rightarrow {p} {\overline{{p}}} $$ is performed using a sample corresponding to an integrated luminosity of 9 $$\,\text {fb} ^{-1}$$ of $$p $$ $$p $$ collision data collected by the LHCb detector at centre-of-mass energies of $$\sqrt{s}$$ = 7, 8 and 13 $$\,\text {Te\hspace{-1.00006pt}V}$$ . The data are described with a model including only intermediate contributions from known $${K} ^{*0}$$ resonances. Evidence for an exotic resonance in the $${\eta _{c}} (1S) {{\pi } ^-} $$ system, reported in a previous analysis of this decay channel, is not confirmed. The inclusive branching fraction of the $${{B} ^0} \rightarrow {\eta _{c}} (1S) {{K} ^+} {{\pi } ^-} $$ decays is measured to be where the first uncertainty is statistical, the second systematic, and the third arises from the limited knowledge of external branching fractions.

C. Beteta

A. Adefisoye

C. Aidala

Lithuania

P. Cartelle

J. Amey

S. Estrada

S. Cuendis

R. Silva

J. Authier

I. Perea

J. Back

P. Rodriguez

J. Souza Leite

C. Pretel

I. Barbosa

R. Barlow

P. Battista

I. Bediaga

N. Behling

S. Andres

C. Betancourt

Ia. Bezshyiko

Ukraine

J. Bhom

M. Bieker

N. Biesuz

P. Billoir

F. Bishop

Amplitude analysis of $$B^0 \rightarrow \eta _c(1S) K^+ \pi ^- $$ decays

We present the first measurements of the forward and midrapidity <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi></math>-meson cross sections from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mo>+</mo><mi>p</mi></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>500</mn></math> and 510 GeV, respectively. We also report the midrapidity <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi><mo>/</mo><msup><mi>π</mi><mn>0</mn></msup></math> ratio at 510 GeV. The forward cross section is measured differentially in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi></math>-meson transverse momentum (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>p</mi><mi>T</mi></msub></math>) from 1.0 to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>6.5</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>c</mi></mrow></math> for pseudorapidity <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3.0</mn><mo>&lt;</mo><mo stretchy="false">|</mo><mi>η</mi><mo stretchy="false">|</mo><mo>&lt;</mo><mn>3.8</mn></math>. The midrapidity cross section is measured from 3.5 to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>44</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>c</mi></mrow></math> for pseudorapidity <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><mi>η</mi><mo stretchy="false">|</mo><mo>&lt;</mo><mn>0.35</mn></math>. Both cross sections serve as critical inputs to an updated global analysis of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi></math>-meson fragmentation functions.

Hungary

N.J. Abdulameer

U. Acharya

A. Adare

N.N. Ajitanand

Japan

Y. Akiba

R. Akimoto

H. Al-Ta’ani

Cross sections of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi></math> mesons in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mo>+</mo><mi>p</mi></math> collisions at forward rapidity at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>500</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math> and central rapidity at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>510</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>