We present the first search for the lepton-flavor-violating decay modes <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>τ</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>∓</mo></mrow></msup></mrow></math> (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo>ℓ</mo><mo>=</mo><mi>μ</mi><mo>,</mo><mi>e</mi></mrow></math>) using the 711 and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>365</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> data samples recorded by the Belle and Belle II detectors, respectively. We use a hadronic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math>-tagging technique to fully reconstruct a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> meson and search for signal decays in the system recoiling against the tagged meson, considering <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>τ</mi></math> decays to either light leptons, one charged hadron, or one charged hadron and a neutral pion. We find no evidence for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>B</mi></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msubsup><mrow><mi>K</mi></mrow><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msubsup><msup><mrow><mi>τ</mi></mrow><mrow><mo>±</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>∓</mo></mrow></msup></mrow></math> decays and set 90% confidence level upper limits on the branching fractions in the range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">[</mo><mn>0.8</mn><mo>,</mo><mn>3.6</mn><mo stretchy="false">]</mo><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup></math>.

I. Adachi

K. Adamczyk

L. Aggarwal

H. Ahmed

H. Aihara

N. Akopov

M. Alhakami

A. Aloisio

N. Althubiti

N. Anh Ky

D.M. Asner

H. Atmacan

V. Aushev

M. Aversano

R. Ayad

V. Babu

H. Bae

N.K. Baghel

S. Bahinipati

P. Bambade

Sw. Banerjee

S. Bansal

M. Barrett

M. Bartl

J. Baudot

A. Baur

A. Beaubien

F. Becherer

J. Becker

J.V. Bennett

F.U. Bernlochner

V. Bertacchi

M. Bertemes

E. Bertholet

M. Bessner

S. Bettarini

V. Bhardwaj

B. Bhuyan

F. Bianchi

D. Biswas

A. Bobrov

D. Bodrov

A. Bolz

A. Boschetti

A. Bozek

M. Bračko

P. Branchini

R.A. Briere

T.E. Browder

A. Budano

S. Bussino

Q. Campagna

M. Campajola

L. Cao

G. Casarosa

C. Cecchi

J. Cerasoli

M.C. Chang

P. Chang

R. Cheaib

P. Cheema

B.G. Cheon

K. Chilikin

K. Chirapatpimol

H.E. Cho

K. Cho

S.J. Cho

S.K. Choi

S. Choudhury

J. Cochran

L. Corona

J.X. Cui

E. De La Cruz-Burelo

S.A. De La Motte

G. de Marino

G. De Nardo

G. De Pietro

R. de Sangro

M. Destefanis

S. Dey

R. Dhamija

A. Di Canto

F. Di Capua

J. Dingfelder

Z. Doležal

I. Domínguez Jiménez

T.V. Dong

X. Dong

M. Dorigo

D. Dossett

S. Dubey

K. Dugic

G. Dujany

P. Ecker

P. Feichtinger

T. Ferber

T. Fillinger

C. Finck

G. Finocchiaro

A. Fodor

Search for Lepton-Flavor-Violating Decay Modes <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mn>0</mn></msup><mo stretchy="false">→</mo><msubsup><mi>K</mi><mi>S</mi><mn>0</mn></msubsup><msup><mi>τ</mi><mo>±</mo></msup><msup><mo>ℓ</mo><mo>∓</mo></msup></math> with Hadronic <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> Tagging at Belle and Belle II

We formalize energy-scaling arguments in the standard model effective field theory (SMEFT) to estimate the effects of operators up to dimension ten. Our approach relies on weakly coupled UV completions with no presumed large hierarchies between the Wilson coefficients. We introduce a classification based on the number of external legs and an energy-counting parameter. We establish a dual expansion in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>v</mi><mo>/</mo><mi mathvariant="normal">Λ</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>E</mi><mo>/</mo><mi mathvariant="normal">Λ</mi></math>. Extending to four-, five-, and six-particle vertices, our framework highlights energy-enhanced operators that dominate high-energy processes at the High Luminosity-Large Hadron Collider. This organization streamlines experimental analyses to only include operators with energetic impact in their analyses and enhances the discoverability of new physics within the SMEFT framework.

United States

Benoît Assi

Adam Martin

Energy-enhanced expansion of the standard model effective field theory

Recent work introduced a new framework for analyzing correlation functions with improved convergence and signal-to-noise properties, as well as rigorous quantification of excited-state effects, based on the Lanczos algorithm and spurious eigenvalue filtering with the Cullum-Willoughby test. Here, we extend this framework to the analysis of correlation-function matrices built from multiple interpolating operators in lattice quantum chromodynamics (QCD) by constructing an oblique generalization of the block Lanczos algorithm, as well as a new physically motivated reformulation of the Cullum-Willoughby test that generalizes to block Lanczos straightforwardly. The resulting block Lanczos method directly extends generalized eigenvalue problem (GEVP) methods, which can be viewed as applying a single iteration of block Lanczos. Block Lanczos provides qualitative and quantitative advantages over GEVP methods analogous to the benefits of Lanczos over the standard effective mass, including faster convergence to ground- and excited-state energies, explicitly computable two-sided error bounds, straightforward extraction of matrix elements of external currents, and asymptotically constant signal-to-noise. No fits or statistical inference are required. Proof-of-principle calculations are performed for noiseless mock-data examples as well as two-by-two proton correlation-function matrices in lattice QCD.

Daniel C. Hackett

Michael L. Wagman

Block Lanczos algorithm for lattice QCD spectroscopy and matrix elements

We investigate tree-level scattering processes involving quarks (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>q</mi></math>) and gluons (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi></math>) mediated by graviton exchange in the framework of agravity, a dimensionless and renormalizable theory of quadratic quantum gravity. Focusing on the ultra-Planckian regime, characterized by the Mandelstam variable <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>s</mi><mo>=</mo><mo stretchy="false">(</mo><msub><mi>p</mi><mn>1</mn></msub><mo>+</mo><msub><mi>p</mi><mn>2</mn></msub><msup><mo stretchy="false">)</mo><mn>2</mn></msup></math>, which corresponds to the total energy squared in the center-of-momentum frame, being much larger than any particle mass scale, we compute the squared amplitudes and analyze the differential cross sections for the processes <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mi>g</mi><mo stretchy="false">→</mo><mi>g</mi><mi>g</mi></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mi>g</mi><mo stretchy="false">→</mo><mi>q</mi><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mi>q</mi><mo stretchy="false">→</mo><mi>g</mi><mi>q</mi></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>q</mi><mi>q</mi><mo stretchy="false">→</mo><mi>q</mi><mi>q</mi></math>. We demonstrate that all amplitudes scale as <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mo>/</mo><mi>s</mi></math> at high energies, in agreement with expectations for a UV-complete theory of gravity. In addition, we explore the issue of unitarity in the presence of higher-derivative ghost modes by analyzing the positivity properties of the squared amplitudes. While IR divergences appear in the forward scattering of massless particles, we show that these are regularized by finite quark masses. Our findings support the viability of agravity as a perturbatively unitary and UV-complete extension of general relativity, capable of consistently describing gravitational interactions among elementary matter fields at trans-Planckian energies.

Brazil

I.F. Cunha

A.C. Lehum

Ultra-Planckian quark and gluon scattering in agravity

In this work we have considered two minimal versions of scotogenic models, where neutrinos acquire masses through a radiative mechanism. We call these two models as Majorana and Dirac scotogenic models. In the former model, neutrinos have Majorana nature, and in the later one, neutrinos are Dirac particles. These two models are related to each other in terms of additional fields and symmetries of the model. Hence, to compare these two models in future experiments, we have analyzed lepton flavor violating (LFV) processes in both of them, in the charged lepton sector. We have found that the 3-body LFV decays in both these models can get different contributions. Among all the LFV decays and after satisfying relevant constraints, we have found that $$\tau \rightarrow 3\mu $$ can have a branching ratio as high as $$10^{-10}(10^{-11})$$ in the Majorana(Dirac) scotogenic model.

India

Raghavendra Hundi

Lepton flavor violation in the Majorana and Dirac scotogenic models

We employ the functional renormalization group flow equations to investigate the phase structure of the two-flavor quark-meson model in the presence of a finite isospin chemical potential, incorporating interactions with omega and rho vector mesons. For comparison, we also compute the phase diagram in the chiral limit using the mean-field approximation. Our findings demonstrate that omega and rho mesons affect the phase structure in markedly distinct ways, and the introduction of an isospin chemical potential leads to significant modifications in the phase boundaries and critical region. Increasing the isospin chemical potential lowers the tricritical points temperature, and tends to suppress the unphysical “back-bending” of the FRG phase boundary at low temperature.

China

Mohammed Osman

Defu Hou

Wentao Wang

Hui Zhang

Functional renormalization group study of the quark-meson model with $$\omega $$ and $$\rho $$ vector mesons

In this paper, we investigate the effects of $\textit{ν}$ and $$ {\overline{\nu}}_{\tau } $$ detection at the DUNE far detector on the experiment’s sensitivity to Non-Standard Interactions (NSI) in neutrino propagation. We show that the strongest observable NSI effect in the $\textit{ν}$ and $$ {\overline{\nu}}_{\tau } $$ appearance probabilities arises from $\textit{ϵ}$ . We have studied the hierarchy sensitivity, CP violation sensitivity and octant sensitivity of DUNE from $\textit{ν}$ and $$ {\overline{\nu}}_{\tau } $$ appearance channels in presence of NSI. We have also studied the detection sensitivity of NSI phases and the future constaints on NSI parameters from the tau neutrino appearance channels in DUNE. Additionally, we examine the role of $\textit{ν}$ detection in constraining the unitary nature of the PMNS matrix. These studies emphasize the importance of incorporating $\textit{ν}$ detection in long-baseline neutrino experiments such as DUNE.

Canada

Xin Yu

Zishen Guan

William Dallaway

Ushak Rahaman

Nikolina Ilic

Effects of tau-neutrino detection on non-standard interactions at DUNE with a short discussion on the nature of neutrino mixing

The island paradigm for an AdS eternal black hole in the Hartle-Hawking state coupled to a finite temperature non-gravitating bath asserts that after the Page time the operators in the black hole interior can be reconstructed using the bath degrees of freedom. We demonstrate this assertion by consideing a special operator $$ {\mathbbm{U}}_{\textrm{bath}} $$ that has nontrivial action only on the bath degrees of freedom. We show via the gravitational Euclidean path integral analysis that though before the Page time $$ {\mathbbm{U}}_{\textrm{bath}} $$ does not translate the operators in the bath to the black hole interior, after the Page time it takes them to the black hole interior.

Krishna Jalan

Roji Pius

Manish Ramchander

Island paradigm and information recovery from radiation

We present predictions for the DIS 1-jettiness event shape $$ {\tau}_1^b $$ , or DIS thrust, using the framework of Soft Collinear Effective Theory (SCET) for factorization, resummation of large logarithms, and rigorous treatment of nonperturbative power corrections, matched to fixed-order QCD away from the resummation region. Our predictions reach next-to-next-to-next-to-leading-logarithmic (N LL) accuracy in resummed perturbation theory, matched to $$ \mathcal{O} $$ ( $$ {\alpha}_s^2 $$ ) fixed-order QCD calculations obtained using the program NLOJet++. We include a rigorous treatment of hadronization corrections, which are universal across different event shapes and kinematic variables $\textit{x}$ and $\textit{Q}$ at leading power, and supplement them with a systematic scheme to remove $$ \mathcal{O} $$ (Λ ) renormalon ambiguities in their definition. The framework of SCET allows us to connect smoothly the nonperturbative, resummation, and fixed-order regions, whose relative importance varies with $\textit{x}$ and $\textit{Q}$, and to rigorously estimate theoretical uncertainties, across a broad range of $\textit{x}$ and $\textit{Q}$ covering existing experimental results from HERA as well as expected new measurements from the upcoming Electron- Ion-Collider (EIC). Our predictions will serve as an important benchmark for the EIC program, enabling the precise determination of the QCD strong coupling $\textit{α}$ and the universal nonperturbative first moment parameter Ω .

June-Haak Ee

South Korea

Daekyoung Kang

Christopher Lee

Austria

Iain Stewart

Precision DIS thrust predictions for HERA and EIC

We study the chiral condensate at finite temperature in AdS/QCD in a time-dependent background, in which the position of the black hole horizon <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>z</mi></mrow><mrow><mi>h</mi></mrow></msub></mrow></math> changes with time, producing an increasing or decreasing temperature. Conformal invariance is broken, as in the soft-wall model, by a static quadratic dilaton. Two different scenarios are analyzed; in the first a general power-law time dependence is assumed for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>z</mi><mi>h</mi></msub></math>, while in the second the energy-momentum tensor at late times reproduces the one found in viscous hydrodynamics. Depending on the rate at which the system evolves, the transition shifts toward lower temperatures. If the chiral condensate is far from equilibrium at low temperatures, oscillations around its equilibrium value are observed before thermalization. A prethermalization stage is found in the chiral limit if the initial condition is set at a temperature close to the critical one. In the hydrodynamic setup the evolution of the medium is slow enough, and the chiral condensate soon matches the equilibrium curve.

Italy

Floriana Giannuzzi

Stefano Nicotri

Out-of-equilibrium chiral condensate in AdS/QCD