We study the relativistic limit of the worldsheet S-matrix of $\textit{AdS}$ × $\textit{S}$ × $\textit{S}$ × $\textit{S}$ strings in the presence of mixed Ramond-Ramond (RR) and Neveu-Schwarz-Neveu-Schwarz (NS-NS) flux and complete the S-matrix bootstrap including the dressing factors for fundamental particles and bound states. Our results agree with the relativistic limit of the recent proposal arXiv:2512.07721.

Italy

Emanuele Cattaneo

Germany

Davide Polvara

United Kingdom

Alessandro Sfondrini

Relativistic limit on the $\textit{AdS}$ 3 × $\textit{S}$ 3 × $\textit{S}$ 3 × $\textit{S}$ 1 string worldsheet

In light of ongoing issues with the first-row unitarity test of the Cabibbo-Kobayashi-Maskawa matrix, we showcase a global fit to measurements of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mo>ℓ</mo><mi>ν</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mi>π</mi><mo>ℓ</mo><mi>ν</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi><mo stretchy="false">→</mo><mi>K</mi><mi>ν</mi></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi><mo stretchy="false">→</mo><mi>K</mi><mi>π</mi><mi>ν</mi></math> decays for the first time. Fitting the semileptonic and three-body <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> decay data simultaneously becomes computationally feasible because we employ a simple form factor parametrization for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> form factor that manifestly connects the semileptonic and pair-production regions. We find good agreement with the data and use our analyses to infer <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> and the parameters for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> form factors. Our result for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><msub><mi>V</mi><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></math> sits close to the results extracted from exclusive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>K</mi><mrow><mo>ℓ</mo><mn>2</mn></mrow></msub></math> and somewhat above the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>K</mi><mrow><mo>ℓ</mo><mn>3</mn></mrow></msub></math> decay and inclusive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> decay result. Moreover, our results for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mo stretchy="false">→</mo><mi>π</mi></math> vector form factor at zero momentum transfer are compatible with lattice QCD determinations, despite not using lattice QCD inputs for this quantity in our fit of the hadronic matrix elements. We are further able to determine some of the pole parameters of the individual scalar and vector <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> resonances with masses below the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> mass. We caution that our results account only for short-distance electromagnetic corrections but not long-distance contributions; this is due to the lack of a consistent description of long-distance corrections to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>K</mi><mi>π</mi></math> matrix elements both above and below threshold for an arbitrary model of the form factors.

Matthew Kirk

Danny van Dyk

Global determination of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo stretchy="false">|</mo><msub><mrow><mi>V</mi></mrow><mrow><mi>u</mi><mi>s</mi></mrow></msub><mo stretchy="false">|</mo></mrow></math>

We investigate S-wave kaon-nucleon (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>K</mi><mi>N</mi></mrow></math>) interactions with strangeness <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mo>=</mo><mo>+</mo><mn>1</mn></math> in lattice QCD using the time-dependent HAL QCD method. Employing the (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>2</mn><mo>+</mo><mn>1</mn></mrow></math>)-flavor gauge configuration with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>π</mi></msub><mo>≈</mo><mn>137</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>K</mi></msub><mo>≈</mo><mn>502</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, we calculate the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>K</mi><mi>N</mi></mrow></math> potentials at the leading order in the derivative expansion. The potentials in both isospin channels (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>I</mi><mo>=</mo><mn>1</mn></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>I</mi><mo>=</mo><mn>0</mn></math>) exhibit repulsion at short distances, while only the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>I</mi><mo>=</mo><mn>0</mn></math> potential has a small attractive pocket at intermediate distances. The phase shifts computed from these potentials show no signals corresponding to resonances or bound states in both isospin channels, suggesting the absence of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi mathvariant="normal">Θ</mi><mo>+</mo></msup><mo stretchy="false">(</mo><mn>1540</mn><mo stretchy="false">)</mo></math> pentaquark in the S-wave <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>K</mi><mi>N</mi></mrow></math> systems. The scattering lengths result in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msubsup><mrow><mi>a</mi></mrow><mrow><mn>0</mn></mrow><mrow><mi>I</mi><mo>=</mo><mn>1</mn></mrow></msubsup><mo>=</mo><mo>−</mo><mn>0.226</mn><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo><msubsup><mrow><mo stretchy="false">(</mo></mrow><mrow><mo>−</mo><mn>0</mn></mrow><mrow><mo>+</mo><mn>5</mn></mrow></msubsup><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>fm</mi></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mi>a</mi><mn>0</mn><mrow><mi>I</mi><mo>=</mo><mn>0</mn></mrow></msubsup><mo>=</mo><mo>+</mo><mn>0.028</mn><mo stretchy="false">(</mo><mn>61</mn><mo stretchy="false">)</mo><msubsup><mo stretchy="false">(</mo><mrow><mo>−</mo><mn>26</mn></mrow><mrow><mo>+</mo><mn>3</mn></mrow></msubsup><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>fm</mi></math>. Our results of the S-wave cross sections for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>I</mi><mo>=</mo><mn>1</mn></math> are consistent with some of the experimental data within <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mi>–</mi><mn>3</mn><mi>σ</mi></math>, while they deviate from others. The results for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>I</mi><mo>=</mo><mn>0</mn></math>, combined with recent studies on chiral perturbation theory, suggest that the scattering amplitudes in this channel are dominated by P-wave components rather than S-wave.

Japan

Kotaro Murakami

Sinya Aoki

Takumi Doi

Yan Lyu

Wren Yamada

<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>S</mi></mrow></math>-wave kaon-nucleon interactions from lattice QCD at the physical point

An analysis of the flavour structure of dimension-6 effective field theory (EFT) operators in multilepton final states is presented, focusing on the interactions of quarks with Z bosons. For the first time, the flavour structure of these operators is disentangled by simultaneously probing the interactions with different quark generations. The analysis targets the associated production of a top quark pair and a Z boson, as well as diboson processes in final states with at least three leptons, which can be electrons or muons. The data were recorded by the CMS experiment in the years 2016–2018 in proton-proton collisions at a centre-of-mass energy of 13 TeV and correspond to an integrated luminosity of 138 fb . Consistency with the standard model of particle physics is observed and limits are set on the selected Wilson coefficients, split into couplings to light- and heavy-quark generations.

Armenia

A. Hayrapetyan

V. Makarenko

A. Tumasyan

Austria

W. Adam

J. Andrejkovic

L. Benato

T. Bergauer

M. Dragicevic

C. Giordano

P. Hussain

M. Jeitler

N. Krammer

A. Li

D. Liko

M. Matthewman

I. Mikulec

J. Schieck

D. Schwarz

R. Schöfbeck

M. Shooshtari

M. Sonawane

W. Waltenberger

C.E. Wulz

Belgium

T. Janssen

H. Kwon

D. Ocampo Henao

T. Laer

P. Mechelen

J. Bierkens

N. Breugelmans

J. D’Hondt

S. Dansana

A. Moor

M. Delcourt

F. Heyen

Y. Hong

P. Kashko

S. Lowette

I. Makarenko

D. Müller

J. Song

S. Tavernier

M. Tytgat

G. Onsem

S. Putte

D. Vannerom

B. Bilin

B. Clerbaux

A. Das

I. Bruyn

G. Lentdecker

H. Evard

L. Favart

P. Gianneios

A. Khalilzadeh

F. Khan

A. Malara

M. Shahzad

L. Thomas

M. Bemden

C. Vander Velde

P. Vanlaer

F. Zhang

M. Coen

D. Dobur

G. Gokbulut

J. Knolle

L. Lambrecht

D. Marckx

K. Skovpen

N. Bossche

J. Linden

J. Vandenbroeck

L. Wezenbeek

S. Bein

A. Benecke

A. Bethani

G. Bruno

A. Cappati

J. De Favereau De Jeneret

C. Delaere

A. Giammanco

A. Guzel

V. Lemaitre

J. Lidrych

P. Malek

P. Mastrapasqua

S. Turkcapar

Brazil

G. Alves

M. Barroso Ferreira Filho

E. Coelho

C. Hensel

T. Menezes De Oliveira

C. Mora Herrera

P. Rebello Teles

M. Soeiro

E. Tonelli Manganote

A. Vilela Pereira

W. Aldá Júnior

H. Brandao Malbouisson

Probing the flavour structure of dimension-6 EFT operators in multilepton final states in proton-proton collisions at $$ \sqrt{s}=13 $$ TeV

Within the framework of nonrelativistic quantum chromodynamics (NRQCD) factorization, we compute the $$ \mathcal{O}\left({v}^4\right) $$ relativistic corrections to the fragmentation of a heavy quark into the color-singlet $$ {}^1{S}_0^{\left[1\right]} $$ and $$ {}^3{S}_1^{\left[1\right]} $$ quarkonium states. Using the Collins-Soper definition of the fragmentation function, we reproduce the known $$ \mathcal{O}\left({v}^2\right) $$ results. We find that the $$ \mathcal{O}\left({v}^4\right) $$ correction gives a positive contribution relative to the leading order result over a wide range of the light-cone momentum fraction $\textit{z}$, while its magnitude remains much smaller than that of the $$ \mathcal{O}\left({v}^2\right) $$ correction. This behavior indicates a good convergence of the NRQCD relativistic expansion in this process. We further extend the calculation to the fragmentation functions in the unequal-mass case at $$ \mathcal{O}\left({v}^4\right) $$ and obtain the corresponding analytical expressions.

China

Sai Cui

Yi-Jie Li

Guang-Zhi Xu

Kui-Yong Liu

Order-$\textit{v}$ 4 corrections to heavy quark fragmentation to $\textit{S}$-wave heavy quarkonium

Measurements of the spin correlation coefficients in the beam basis are presented for top quark-antiquark (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi><mover accent="true"><mi>t</mi><mo stretchy="false">¯</mo></mover></math>) systems produced in proton-proton collisions 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> collected by the CMS experiment in 2016–2018, and corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi><mover accent="true"><mi>t</mi><mo stretchy="false">¯</mo></mover></math> system is reconstructed from final states containing an electron or muon and jets. Together with the previously reported results in the helicity basis, these measurements are used to decompose the system into the Bell and spin eigenstates in various kinematic regions. The spin correlation coefficients are also used to evaluate properties of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>t</mi><mover accent="true"><mi>t</mi><mo stretchy="false">¯</mo></mover></math> quantum state, such as the purity, von Neumann entropy, and entanglement. All results are consistent with standard model predictions.

P.S. Hussain

T. Van Laer

P. Van Mechelen

A. De Moor

G.P. Van Onsem

S. Van Putte

A.K. Das

I. De Bruyn

G. De Lentdecker

F.A. Khan

M.A. Shahzad

A. Sharma

M. Vanden Bemden

M. De Coen

K. Kaspar

D. Kavtaradze

A.M. Tomaru

N. Van Den Bossche

J. van der Linden

H. Aarup Petersen

F. Gameiro Casalinho

A.O. Guzel

G.A. Alves

D. Matos Figueiredo

E.J. Tonelli Manganote

W.L. Aldá Júnior

Characterization of the quantum state of top quark pairs produced in proton-proton collisions 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> using the beam and helicity bases

We study spacetime four-point functions of chiral primary operators for superstrings propagating in AdS $\textit{× S}$ $\textit{× T}$ from the worldsheet perspective, allowing for external states with arbitrary spectral flow charges. We work at small boundary cross-ratio and consider both extremal (supersymmetry-protected) and non-extremal configurations. The string correlators involve a non-trivial integration over the worldsheet moduli, and we demonstrate how the exchange of short and long strings is encoded in distinct integration regions. We interpret our results in terms of the operator product expansion in the boundary theory, and make explicit the precise matching with the available data for the relevant holographic correlators.

Argentina

Emiliano Barone

Sergio Iguri

Nicolas Kovensky

Julián Toro

Superstring four-point functions in AdS3 $\textit{× S}$ 3 $\textit{× T}$ 4

In this work, a charged fluid system is studied by employing the complexity factor formalism for a static spherical spacetime. We proceed by calculating two distinct mass functions and obtaining the Einstein field equations for the anisotropic fluid. Following Herrera’s methodology, we designate $${Y}_{TF}$$ as the complexity factor as it integrates the two fundamental dynamic components like the density inhomogeneity and pressure anisotropy. Additionally, the field equations are addressed by applying a few constraints, with the first being the condition of zero complexity. By implementing two distinct forms for the radial metric potential, we derive two independent solutions. The unknowns involved in these models are then found using the junction conditions by taking into account the Reissner–Nordström exterior metric. Subsequently, observed data from multiple stars is used to generate a visual depiction of the obtained solutions. Our analysis demonstrates that both proposed models maintain physically stable and viable profiles, highlighting the critical role of the vanishing complexity condition in constructing anisotropic fluid solutions under the presence of an electric charge.

Pakistan

Azerbaijan

Tayyab Naseer

M. Sharif

Javeria Javid

Saudi Arabia

Jordan

Kottakkaran Nisar

Mohammed Zakarya

Orthogonal splitting of the Riemann curvature tensor and implications of resulting scalar(s) on compact stellar evolution

A model-agnostic search for Beyond the Standard Model physics is presented, targeting final states with at least four light leptons (electrons or muons). The search regions are separated by event topology and unsupervised machine learning is used to identify anomalous events in the full 140 fb $$^{-1}$$ of proton–proton collision data collected with the ATLAS detector during Run 2. No significant excess above the Standard Model background expectation is observed. Model-agnostic limits are presented in each topology, along with limits on several benchmark models including vector-like leptons, wino-like charginos and neutralinos, or smuons. Limits are set on the flavourful vector-like lepton model for the first time.

France

G. Aad

Norway

E. Aakvaag

United States

B. Abbott

United Arab Emirates

S. Abdelhameed

K. Abeling

N. Abicht

S. Abidi

M. Aboelela

Morocco

A. Aboulhorma

Israel

H. Abramowicz

Y. Abulaiti

B. Acharya

A. Ackermann

C. Adam Bourdarios

Poland

L. Adamczyk

Search for Beyond the Standard Model physics with anomaly detection in multilepton final states in $\textit{pp}$ collisions at $$\sqrt{s}=13~\textrm{TeV}$$ with the ATLAS detector