We study the new $Z'$ boson as a portal for the production of Higgs bosons $h_0$ and $H_0$ predicted by the Bestest Little Higgs Model through Higgs-strahlung processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ . We focus on the resonant and nonresonant effects of the $Zh_0, ZH_0$ signals. In our analysis, we consider the center-of-mass energies of $\sqrt{s}=3, 4, 6, 10, 30$ TeV and integrated luminosities of ${\cal{L}}=2, 4, 6, 10, 30$ ${ {\rm{ab}}^{-1}}$ projected for a future muon collider. The possibility of performing precision measurements for Higgs bosons $h_0$ and $H_0$ is very promising for the future muon collider. Furthermore, our results may be useful to the High Energy Physics community. Complementarily, we generate and provide the Feynman rules necessary for studying processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ .

J.M. Martínez-Martínez

A. Gutiérrez-Rodríguez

E. Cruz-Albaro

M.A. Hernández-Ruíz

New $\textit{Z}$' boson of the bestest little Higgs model as a portal to signatures of Higgs bosons $\textit{h}$ $_{0}$ and $\textit{H}$ $_{0}$ at the future muon collider

We revisit the calculation of the evolution equations for four unpolarized twist-3 transverse momentum dependent (TMD) parton distribution functions (PDFs) at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msub><mi>α</mi><mi>s</mi></msub><mo stretchy="false">)</mo></math>. Unlike the existing calculations in the literature, which are based on the background field method, we derive the evolution equations directly through diagram expansion. Additionally, instead of using the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>δ</mi></math> regulator, we employ the exponential regulator to regularize the rapidity divergences. We find that the evolutions of the four twist-3 TMD PDFs are governed by eight homogeneous equations. Our evolution kernels agree with one set of results in the literature, but differ from another by a sign. Considering the advantages of the exponential regulator in high-order perturbative calculations, our results are crucial for computing the twist-3 TMD PDFs at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msubsup><mi>α</mi><mi>s</mi><mn>2</mn></msubsup><mo stretchy="false">)</mo></math>.

China

Xue-Tao Liu

Ping-An Liu

Yu-Lu Liu

An-Ping Chen

Evolution of unpolarized transverse momentum dependent parton distributions of twist-3

The nonlinear <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Σ</mi></math> model minimally coupled with Maxwell theory in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>3</mn><mo>+</mo><mn>1</mn></math> dimensions possesses a topologically nontrivial sector characterized by lasagnalike configurations. We demonstrate that, when a specific quantization condition is met, the associated second-order field equations admit a first-order Bogomol’nyi-Prasad-Sommerfield system. This discloses the existence of a (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>1</mn><mo>+</mo><mn>1</mn></mrow></math>)-dimensional supersymmetric extension with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">N</mi><mo>=</mo><mn>2</mn></math> supercharges. We examine its imprint on the time-dependent regime, with particular emphasis on the transition from integrability to chaos.

Chile

Fabrizio Canfora

Argentina

Nicolás Grandi

Italy

Marcelo Oyarzo

Existence of a supersymmetric extension of the gauged nonlinear <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="normal">Σ</mi></math> model and the transition from integrability to chaos

In this note, we derive and interpret hidden zeros of tree-level amplitudes of various theories, including Yang–Mills, non-linear sigma model, special Galileon, Dirac–Born–Infeld, and gravity, by utilizing universal expansions of tree-level amplitudes which expand amplitudes of different theories to those of bi-adjoint scalar theory. Hidden zeros of above amplitudes are attributed to zeros of bi-adjoint scalar amplitudes which can be easily proved. For unordered amplitudes such as gravitational ones, the kinematic condition for zeros causes potential divergences of propagators. We also show the detailed mechanism of eliminating such divergences.

Hao Huang

Ye Yang

Kang Zhou

Note on hidden zeros and expansions of tree-level amplitudes

We compute the branching fractions of vector quarkonia ( $$V_Q=J/\psi , \psi ', \Upsilon (nS)$$ ) decays into neutrino pairs, considering both Dirac and Majorana types, within the Standard Model (SM) and beyond. The vector nature of quarkonium states yields a decay width in the SM that depends upon the weak vector coupling of the heavy quark, offering the possibility to measure the weak mixing angle at the quarkonia mass scales. If neutrinos have non-standard neutral weak couplings, this could help to distinguish the nature of neutrinos in principle.

Mexico

G. Hernández-Tomé

South Korea

C. Kim

G. Castro

Invisible decays of vector Charmonia and Bottomonia to determine the weak mixing angle at quarkonia scale

Parametric deviations of quasinormal modes (QNMs) is a common feature of beyond General Relativity (GR) theories. For theories with additional degrees of freedom, such as scalars and vectors, new family of modes might appear, usually called scalar-led and vector-led modes. Although a power series expansion in terms of the new parameters entering the potential is usually suitable to describe the frequency of the modes, the time-evolution of signals might present a richer structure, with different behavior in the tail, the presence of new modes (such as massive modes), or even instabilities. All these features are not explicitly exposed by a pure frequency domain analysis and might give hints of new physics. In this paper, we investigate the time evolution of signals considering potentials that slightly deviate from the ones coming from GR, looking into scalar, vector and metric perturbations. We focus on deviations that can be parametrized by a sum of $$\sim 1/r^j$$ terms in the effective potential, analyzing the effect of each term on the time domain profile

Brazil

Orival de Medeiros

Mateus Corrêa

Caio Macedo

Time evolution of perturbations in quasi-Schwarzschild black holes

On the basis of computer simulation, the ionization energy loss distributions (spectra) of high-energy positrons impinging on a silicon crystal at various angles $$\psi $$ with respect to the axis $$\langle 100\rangle $$ are considered. The method of simulation of high-energy particle ionization loss in oriented crystals is presented in detail. It is demonstrated that along with the probability of particle close collisions with atoms, the probability of distant collisions can be also sensitive to the particle position in the crystal lattice. Evolution of the ionization loss spectra with the change of crystal orientation relative to the incident particle momentum from the axial $$\langle 100\rangle $$ to the planar (100) and (110) with the increase of $$\psi $$ is investigated. It is shown that in the transition $$\langle 100\rangle \rightarrow (100)$$ the most probable energy loss $$E_\mathrm{{MP}}$$ experiences a sharp maximum and discontinuity, while in the transition $$\langle 100\rangle \rightarrow (110)$$ the amplitude of its variation is much smaller. Behavior of the average restricted energy loss $$E_\mathrm{{AV}}$$ in these transitions is investigated as well. Correlation of the dependences of $$E_\mathrm{{MP}}$$ and $$E_\mathrm{{AV}}$$ on $$\psi $$ with the change of the particle motion regime is discussed.

Ukraine

S. Trofymenko

I. Kyryllin

Evolution of high-energy positron ionization loss spectra in a silicon crystal with the change of its orientation from axial to planar

The goal of our work is to explore the topology classifications of black holes in Massive gravity. We use Duan's <italic>&#981;</italic>-mapping theory to study the topology classes. This tool helps us to compute the integer numbers to characterize the topological features of the black hole. Our analysis is carried out across two different thermodynamic ensembles. These statistical ensembles are the canonical ensemble and the mixed canonical ensemble. Every ensemble corresponds to a different thermodynamic condition, allowing us to investigate how the black holes respond to other physical conditions. Thus, employing these analytical techniques, it is expected that further insights into topological and thermodynamic aspects of black holes in these modified gravity frameworks can be explored. This work helps to shed light on black hole dependencies on gravitational theories and conditions in thermal processes and thus expands the knowledge, proposing a new essence of black holes.

Pakistan

Tehreem Aslam

Muhammad Yasir

Shahid Qaisar

Azerbaijan

Faisal Javed

Saudi Arabia

Bander Almutairi

Thermodynamic topology of black hole in Massive gravity with generalized Barrow modification of entropy

A precise determination of the CKM angle $\textit{γ}$ from $$ {B}_s^0 $$ oscillations in $$ {B}_s^0\to {D}_s^{\mp }{K}^{\pm } $$ decays offers a critical test of the Standard Model and probes for new physics. We present a comprehensive study on the prospects of measuring $\textit{γ}$ at a future Tera-$\textit{Z}$ factory, utilizing the baseline detector concept of the Circular Electron Positron Collider (CEPC). A two-dimensional simultaneous fit framework, incorporating flavor tagging, decay time resolution modeling, and acceptance corrections, is developed using full Monte Carlo simulations of $$ {B}_s^0\to {D}_s^{\mp}\left(\to {K}^{\mp }{K}^{\pm }{\pi}^{\mp}\right){K}^{\pm } $$ decays and inclusive background processes. The effective flavor tagging power reaches 23.6%, while the decay time resolution is determined to be 26 fs. Projecting to full statistics of signal events across three dominant $$ {D}_s^{-} $$ decay channels, we estimate a statistical precision of $\textit{σ}$($\textit{γ}$) = 0$\textit{.}$69 , which corresponds to 4.1 Tera-$\textit{Z}$ boson equivalent data. This study has established the feasibility of sub-degree level $\textit{γ}$ measurements at a $\textit{Z}$ factory, highlighting its unique advantages in time-dependent $\textit{CP}$ violation studies through ultra-precise vertexing and background suppression capabilities.

Ji Peng

Mingrui Zhao

Xiaolin Wang

Manqi Ruan

Hengne Li

Shanzhen Chen

Prospect for measurement of $\textit{CP}$-violating observables in $$ {B}_s^0\to {D}_s^{\mp }{K}^{\pm } $$ decays at a future $\textit{Z}$ factory

We show that the Mathieu groups $\textit{M}$ and $\textit{M}$ in the isometry group of the odd Leech lattice do not lift to subgroups of the automorphism group of its lattice vertex operator (super)algebra. In other words, the subgroups 2 .$\textit{M}$ and 2 .$\textit{M}$ of the automorphism group of the odd Leech lattice vertex operator algebra are non-split extensions. Our method can also confirm a similar result for the Conway group Co and the Leech lattice, which was already shown by Griess in [1]. This study is motivated by the moonshine-type observation on the $$ \mathcal{N} $$ = 2 extremal elliptic genus of central charge 24 by Benjamin, Dyer, Fitzpatrick, and Kachru [2]. We also investigate weight-1 and weight- $$ \frac{3}{2} $$ currents invariant under the subgroup 2 .$\textit{M}$ or 2 .$\textit{M}$ of the automorphism group of the odd Leech lattice vertex operator algebra, and revisit an $$ \mathcal{N} $$ = 2 superconformal algebra in it.

Japan

Masaki Okada

On the symmetry of odd Leech lattice CFT