This Letter presents a combination of searches for Higgs boson pair (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math>) production performed by the ATLAS and CMS Collaborations using proton-proton collision datasets recorded at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> during the Large Hadron Collider Run 2, corresponding to integrated luminosities ranging between 126 and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>140</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. The upper limit at the 95% confidence level on the total <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> signal strength, defined as the ratio of the measured cross section to the standard model (SM) prediction, corresponds to 2.5, with an expected value of 1.7 (2.8) assuming the absence (presence) of the SM <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> signal. The strength of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> signal is measured to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mn>0.8</mn><mrow><mo>−</mo><mn>0.7</mn></mrow><mrow><mo>+</mo><mn>0.9</mn></mrow></msubsup></math> relative to the SM prediction. The observed significance is found to be 1.1 standard deviations whereas 1.3 are expected for the SM <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> signal. Constraints are set on the Higgs boson trilinear self-coupling and on the couplings of two Higgs bosons to two vector bosons, both normalized to the SM predictions and denoted as <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>κ</mi><mi>λ</mi></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>κ</mi><mrow><mn>2</mn><mi>V</mi></mrow></msub></math>, respectively. The observed individual constraints at the 95% confidence level are <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo>−</mo><mn>0.71</mn><mo>&lt;</mo><msub><mrow><mi>κ</mi></mrow><mrow><mi>λ</mi></mrow></msub><mo>&lt;</mo><mn>6.1</mn></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>0.73</mn><mo>&lt;</mo><msub><mi>κ</mi><mrow><mn>2</mn><mi>V</mi></mrow></msub><mo>&lt;</mo><mn>1.3</mn></math>, while the expected constraints assuming the presence of the SM <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>H</mi><mi>H</mi></math> signal are <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>−</mo><mn>1.3</mn><mo>&lt;</mo><msub><mi>κ</mi><mi>λ</mi></msub><mo>&lt;</mo><mn>6.7</mn></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>0.66</mn><mo>&lt;</mo><msub><mi>κ</mi><mrow><mn>2</mn><mi>V</mi></mrow></msub><mo>&lt;</mo><mn>1.4</mn></math>.

France

G. Aad

Norway

E. Aakvaag

United States

B. Abbott

United Arab Emirates

S. Abdelhameed

Germany

K. Abeling

N.J. Abicht

S.H. Abidi

M. Aboelela

Morocco

A. Aboulhorma

Israel

H. Abramowicz

Italy

B.S. Acharya

A. Ackermann

C. Adam Bourdarios

Poland

L. Adamczyk

S.V. Addepalli

United Kingdom

M.J. Addison

J. Adelman

Türkiye

A. Adiguzel

T. Adye

A.A. Affolder

Y. Afik

Spain

M.N. Agaras

A. Aggarwal

Romania

C. Agheorghiesei

A. Ahmad

F. Ahmadov

S. Ahuja

China

X. Ai

G. Aielli

A. Aikot

M. Ait Tamlihat

B. Aitbenchikh

Sweden

T.P.A. Åkesson

Japan

D. Akiyama

N.N. Akolkar

S. Aktas

G.L. Alberghi

Canada

J. Albert

Switzerland

U. Alberti

P. Albicocco

G.L. Albouy

S. Alderweireldt

Z.L. Alegria

CERN

M. Aleksa

I.N. Aleksandrov

C. Alexa

Greece

T. Alexopoulos

F. Alfonsi

M. Algren

M. Alhroob

Czechia

B. Ali

H.M.J. Ali

S. Ali

S.W. Alibocus

South Africa

M. Aliev

G. Alimonti

C. Allaire

B.M.M. Allbrooke

D.R. Allen

J.S. Allen

J.F. Allen

Australia

C.S. Alley

E.R. Almazan

A. Aloisio

Argentina

F. Alonso

C. Alpigiani

Z.M.K. Alsolami

A. Alvarez Fernandez

M. Alves Cardoso

M.G. Alviggi

M. Aly

Brazil

Y. Amaral Coutinho

A. Ambler

C. Amelung

M. Amerl

T. Amezza

B. Amini

K. Amirie

A. Amirkhanov

Portugal

S.P. Amor Dos Santos

D. Amperiadou

S. An

C. Anastopoulos

T. Andeen

J.K. Anders

A.C. Anderson

A. Andreazza

S. Angelidakis

A. Angerami

A.V. Anisenkov

A. Annovi

C. Antel

E. Antipov

M. Antonelli

F. Anulli

M. Aoki

T. Aoki

M.A. Aparo

L. Aperio Bella

Combination of ATLAS and CMS Searches for Higgs Boson Pair Production at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></mrow></math>

M-theory geometric engineering on manifolds of special holonomy yields a rich class of novel field theories. In this paper, we construct new 3d 𝒩 = 2 and 𝒩 = 4 gauge theories, realized as mass-deformations of theories with 16 supercharges, within this framework. These arise from non-compact 8d geometries given by fibrations of ℝ /Γ over Bieberbach 4-manifolds. The existence of consistent Spin(7)-structures on the 8d spaces requires the rotational holonomy of the Bieberbach spaces to act on the Sp(1)-structure of the fibers. Furthermore, we analyze Higgsing the 7d 𝒩 = 1 ADE gauge theories induced by the action of a permutation group on the centres of the corresponding ℝ /Γ spaces. We show that this operation admits a natural interpretation in terms of nilpotent, upper-triangular, Higgsing, although it breaks supersymmetry. Supersymmetry is restored by fibering the singular geometry over a compact internal space, whose structure group is chosen to coincide with the permutation group to implement the nilpotent Higgsing. We refer to such backgrounds as T-geometries, where “T” denotes the triangular nature of the nilpotent Higgsing. Within this framework, we investigate the nilpotent Higgsing of the 3d 𝒩 = 2 and 4d 𝒩 = 1 theories, where the rotational holonomy groups of the Bieberbach spaces realize the permutation groups. We demonstrate that the Higgs branch moduli are encoded by specific elements of the Slodowy slices associated with nilpotent elements. Moreover, we demonstrate that additional elements of the same slice give rise to non-chiral charged matter under the unbroken gauge algebra. We establish that both the Higgs branch moduli and the charged matter are massless and admit a natural interpretation as localized matter.

Marwan Najjar

M-theory and T-geometry: Higgs branch moduli and charged matter

This Letter presents a measurement of prompt charged-particle production in proton-oxygen interactions at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><msub><mi>s</mi><mi>NN</mi></msub></msqrt><mo>=</mo><mn>9.62</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> center-of-mass energy with the ATLAS detector, corresponding to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>634</mn><mtext> </mtext><mtext> </mtext><mi>μ</mi><mrow><msup><mrow><mi mathvariant="normal">b</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></mrow></math> of integrated luminosity. A total of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>246</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></math> selected events have at least one track with transverse momentum <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>p</mi><mi mathvariant="normal">T</mi></msub><mo>&gt;</mo><mn>500</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math> and 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>2.5</mn></math>. The measured fiducial proton-oxygen cross section is <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>σ</mi><mrow><mi>fid</mi><mo>.</mo></mrow><mrow><mi>p</mi><mi mathvariant="normal">O</mi></mrow></msubsup><mo>=</mo><mn>396</mn><mo>±</mo><mn>6</mn><mo stretchy="false">(</mo><mrow><mi>exp</mi><mo>.</mo></mrow><mo stretchy="false">)</mo><mo>±</mo><mn>9</mn><mo stretchy="false">(</mo><mrow><mi>lumi</mi><mo>.</mo></mrow><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>mb</mi></math> and the extrapolated inelastic proton-air cross section is <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>σ</mi><mrow><mi>inel</mi><mo>.</mo></mrow><mrow><mi>p</mi><mo>+</mo><mi>air</mi></mrow></msubsup><mo>=</mo><mn>406</mn><mo>±</mo><mn>6</mn><mo stretchy="false">(</mo><mrow><mi>exp</mi><mo>.</mo></mrow><mo stretchy="false">)</mo><mo>±</mo><mn>9</mn><mo stretchy="false">(</mo><mrow><mi>lumi</mi><mo>.</mo></mrow><mo stretchy="false">)</mo><mo>±</mo><mn>28</mn><mo stretchy="false">(</mo><mrow><mi>th</mi><mo>.</mo></mrow><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>mb</mi></math>. Measurements of charged-particle multiplicity, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>p</mi><mi mathvariant="normal">T</mi></msub></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>η</mi></math> distributions are an order-of-magnitude more precise than differences between hadronic-interaction models. These results enable improved modeling of cosmic-ray air showers, which is important for astroparticle physics.

J. Ackerschott

M. Apicella

C. Appelt

A. Apyan

M. Arampatzi

Measurement of Charged-Particle Production in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><msub><mi>s</mi><mrow><mi>NN</mi></mrow></msub></msqrt><mo>=</mo><mn>9.62</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> Proton-Oxygen Collisions as a Probe of Cosmic-Ray Air Showers with the ATLAS Detector

We investigate DC transport in a top-down construction of thermal QGP-like theories using a holographic $$ \mathcal{M} $$ -theoretic background, incorporating quartic curvature corrections. The DC and Hall conductivities are computed from the Dirac-Born-Infeld (DBI) action of the corresponding type-IIA probe $\textit{D}$6 flavor branes via the reality condition method proposed in [1, 2]. We further analyze pair-production contributions in the presence and absence of an external magnetic field and work out regimes where thermal pair production dominates over charge carrier transport. These findings extend earlier AdS/CFT results to non-conformal, higher-derivative settings relevant to thermal QGP-like theories.

India

Shivam Kushwah

Charge transport in magnetized holographic $$ \mathcal{M} $$ -QGP

Entanglement is a key property of quantum systems. In this Letter the first measurements of quantum entanglement between spins in pairs of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math> bosons are reported, using proton-proton collision data from the Large Hadron Collider (LHC) at center-of-mass energies of 13 and 13.6 TeV, recorded with the ATLAS detector. Measurements of angular observables sensitive to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi><msup><mi>Z</mi><mo>*</mo></msup></math> spin-density-matrix elements in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>H</mi><mo stretchy="false">→</mo><mi>Z</mi><msup><mrow><mi>Z</mi></mrow><mrow><mo>*</mo></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>−</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> process yield coefficients <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>C</mi></mrow><mrow><mn>2</mn><mo>,</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>,</mo><mo>−</mo><mn>1</mn></mrow></msub><mo>=</mo><mo>−</mo><mn>0.71</mn><mo>±</mo><mn>0.45</mn></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>C</mi><mrow><mn>2</mn><mo>,</mo><mn>2</mn><mo>,</mo><mn>2</mn><mo>,</mo><mo>−</mo><mn>2</mn></mrow></msub><mo>=</mo><mn>0.08</mn><mo>±</mo><mn>0.44</mn></math>, consistent with their Standard Model predictions. A complementary hypothesis test using the full angular distribution, and relying on several Standard Model assumptions in the decays, provides substantially higher sensitivity to quantum correlations and disfavors the separable-state hypothesis at a significance of 4.7 standard deviations (expected <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4.9</mn><mi>σ</mi></math>) relative to the entangled Standard Model hypothesis. These results provide strong evidence of quantum entanglement between massive bosons (spin qutrits) at the electroweak scale.

J.A. Aguilar Saavedra

Measurements of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math>-Boson Pair Entanglement in Decays of Higgs Bosons at the ATLAS Experiment

Currently, the kinetic mass is defined in terms of the pole mass and operators at order $$1/{m}_{Q}^{2}$$ , which are known to N LO accuracy in $\textit{α}$ . At the same time, the Heavy Quark Expansion (HQE) for inclusive semileptonic decays is known up to and including terms of order $$1/{m}_{Q}^{5}$$ . Therefore, it is desirable to extend the definition of the kinetic mass to higher orders in 1/$\textit{m}$ . The original kinetic mass is based on the hadron-mass formula in Heavy Quark Effective Theory (HQET). However, the HQE is formulated in terms of matrix elements defined in full QCD to avoid the appearance of non-local matrix elements. To match this, we develop a definition of the kinetic mass rooted in full QCD. Starting from the hadron-mass formula derived from the energy-momentum tensor of full QCD, we define a relation between a general mass and the pole mass. Using a simple cut-off scheme, we compute a generalized kinetic mass at one loop to all powers of 1/$\textit{m}$ , which reproduces the well-known results for the kinetic mass up to $$1/{m}_{Q}^{2}$$ . Our approach opens the road to a consistent use of the kinetic mass at higher-orders in the heavy quark expansion.

Thomas Mannel

Ilija Milutin

Netherlands

Rens Verkade

K. Keri Vos

Extending the kinetic mass to higher orders in 1$\textit{/m}$ $\textit{Q}$

A search is performed for the electroweak pair production of charginos and associated production of a chargino and neutralino, each of which decays through an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>R</mi></math>-parity-violating coupling into a lepton and a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>W</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>Z</mi></math>, or Higgs boson. This search targets the Higgs boson decay channel of the charginos and neutralinos, using events with three or more <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi></math>-tagged jets and one or two electrons or muons. The analyzed data corresponds to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>140</mn><mtext> </mtext><mtext> </mtext><msup><mrow><mi>fb</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>56</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> of proton-proton collision data produced by the Large Hadron Collider at center-of-mass energies of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13.6</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>, respectively, collected by the ATLAS experiment between 2015 and 2023. The data are found to be consistent with predictions from the Standard Model. The results are interpreted as limits at 95% confidence level on model-independent cross sections for processes beyond the Standard Model. Limits are also set on the production of charginos and neutralinos for a minimal supersymmetric Standard Model with an additional <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mo>−</mo><mi>L</mi></math> gauge symmetry that is spontaneously broken. Charginos and neutralinos with masses between 150 GeV and 1100 GeV are excluded at 95% confidence level for a scenario in which they decay via Higgs bosons, assuming equal decay branching fractions to each lepton flavor. Additional limits on chargino and neutralino production are derived for flavor-specific decay scenarios where the charginos decay into a single lepton flavor.

Search for charginos and neutralinos with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi><mo>−</mo><mi>L</mi></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>R</mi></math>-parity violating decays in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> and 13.6 TeV <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>p</mi><mi>p</mi></math> collisions with the ATLAS detector

The Lorentz-contracted electromagnetic fields of the ions in ultra-relativistic heavy-ion collisions generate intense quasi-real photon fluxes. These lead to photon-induced interactions that are observed in ultra-peripheral collisions (UPCs), such as vector meson and lepton-pair production. The high photon flux also enables the occurrence of multiple photon-induced processes in a single collision. Presented is the first measurement of the coincident production of <math altimg='si2.svg'><mrow><mi>&#947;</mi><mi>&#947;</mi><mo>&#8594;</mo><msup><mi>&#956;</mi><mo>+</mo></msup><msup><mi>&#956;</mi><mo>&#8722;</mo></msup></mrow></math> and <math altimg='si4.svg'><mrow><mi>&#947;</mi><mo linebreak='goodbreak'>+</mo><mi>A</mi><mo>&#8594;</mo><msup><mi>&#961;</mi><mn>0</mn></msup><mo linebreak='goodbreak'>+</mo><mi>A</mi></mrow></math> in UPC Pb+Pb collisions at centre-of-mass energies of 5.02 TeV and 5.36 TeV with the ATLAS detector at the Large Hadron Collider. The coincident <italic>&#961;</italic> 0 is identified via its decay into a <math altimg='si5.svg'><mrow><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup></mrow></math> pair, with the selected <math altimg='si5.svg'><mrow><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup></mrow></math> sample also containing the non-resonant continuum contribution. The rate of the coincident process relative to the exclusive <math altimg='si2.svg'><mrow><mi>&#947;</mi><mi>&#947;</mi><mo>&#8594;</mo><msup><mi>&#956;</mi><mo>+</mo></msup><msup><mi>&#956;</mi><mo>&#8722;</mo></msup></mrow></math> process is measured differentially in intervals of forward event activity, quantified by the Zero Degree Calorimeters. The relative rate of coincident <italic>&#961;</italic> 0 production, including non-resonant <math altimg='si5.svg'><mrow><msup><mi>&#960;</mi><mo>+</mo></msup><msup><mi>&#960;</mi><mo>&#8722;</mo></msup></mrow></math> contributions, is measured to be <math altimg='si6.svg'><mrow><mrow><mo>(</mo><mn>9.3</mn><mspace width='0.16em' /><mo>&#177;</mo><mn>0.4</mn><mspace width='0.16em' /><mrow><mo mathvariant='normal'>(</mo><mtext>stat</mtext><mo>.</mo><mo>)</mo></mrow><mspace width='0.16em' /><mo>&#177;</mo><mn>0.2</mn><mspace width='0.16em' /><mrow><mo mathvariant='normal'>(</mo><mtext>syst</mtext><mo>.</mo><mo>)</mo></mrow><mo>)</mo></mrow><mo linebreak='goodbreak'>&#215;</mo><msup><mn>10</mn><mrow><mo>&#8722;</mo><mn>3</mn></mrow></msup></mrow></math>, summed over forward event activity. Correlations between the dimuon kinematic properties, such as its mass, and the coincident <italic>&#961;</italic> 0 meson production rate, are also presented. These measurements confirm the presence of multi photon-induced processes in UPC collisions, and can provide new insight into the impact parameter dependence of photon-induced vector meson production.

Y. Abulaiti

M. Akbiyik

A.V. Akimov

W. Alkakhi

P.P. Allport

C.G. Ames

D. Amidei

K.R. Amos

Measurement of coincident photon-initiated processes in ultra-peripheral Pb+Pb collisions with the ATLAS detector

A search for quantum black holes in electron+jet or muon+jet final states with high invariant mass is performed. The analysis uses data from <math altimg='si13.svg'><mrow><msqrt><mi>s</mi></msqrt><mo linebreak='goodbreak'>=</mo><mn>13.6</mn><mspace width='0.33em' /><mtext>TeV</mtext></mrow></math> <italic>pp</italic> collisions recorded by the ATLAS detector between 2022 and 2024 during Run 3 of the Large Hadron Collider, corresponding to an integrated luminosity of <math altimg='si14.svg'><mrow><mn>164</mn><mspace width='0.33em' /><msup><mrow><mtext>fb</mtext></mrow><mrow><mo>&#8722;</mo><mn>1</mn></mrow></msup></mrow></math>. This search is strongly motivated by a dramatic increase of the production cross-section by up to an order of magnitude for the highest masses considered, thanks to the small increase of 0.6&#8201;TeV in centre-of-mass energy between Run 2 and Run 3. No significant excess above the Standard Model background is observed, and 95% CL upper limits are set on the production cross-section times branching ratio in several benchmark models, reaching a mass scale of 9.4&#8201;TeV. These represent the strongest exclusion limits to date on quantum black hole production.

S.J. Arbiol Val

Search for quantum black holes in lepton+jet final states using proton–proton collisions at <math altimg='si13.svg'><mrow><msqrt><mi>s</mi></msqrt><mo linebreak='goodbreak'>=</mo><mn>13.6</mn><mspace width='0.33em' /><mtext>TeV</mtext></mrow></math> with the ATLAS detector

We apply the localization method to the BFSS matrix model with a particular class of boundary conditions, that is related to a scattering problem of 11-dimensional M-theory. For the boundary condition that corresponds to the three-point amplitude of gravitons, we exactly compute the partition function of the model based on the localization method. We find that the result correctly reproduces the expected momentum dependence of the three point amplitude.

Yuhma Asano

Goro Ishiki

Yoshua Murayama

Localization of the BFSS matrix model and three-point amplitude in M-theory