We study the strong decay of $$D_{s0}^*(2317)^+$$ to $$D_s^+ \pi ^0$$ considering the coupled channels of $$D^0 K^+, D^+ K^0, D_s^+ \eta $$ and $$D_s^+ \pi ^0$$ within a picture for the interaction based on the local hidden gauge approach. We also address the problem of the radiative decay to $$D_s^{*+} \gamma $$ , using the same information obtained from the molecular picture. We obtain a strong width of the $$D_{s0}^*(2317)^+$$ of about $$77 \,\mathrm keV$$ from coupled channels interaction and a radiative decay of about $$1.7 \,\mathrm keV$$ . We also show that the extra consideration of $$\pi ^0-\eta $$ mixing can double the strong decay width to values around $$140 \,\mathrm keV$$ . The anomalous terms for the radiative decay are considered for the first time, but they are found negligible. We make a thorough discussion of this and other results to the light of the recent measurement of Belle for the ratio of these two decay modes, and make a call for the precise measurement of the two decay widths independently to clarify the present situation concerning the nature of the $$D_{s0}^*(2317)^+$$ state.

China

Pei-Sen Su

Wen-Tao Lyu

Wei-Hong Liang

Spain

Eulogio Oset

The $$D_{s0}^*(2317)^+$$ decay to $$D_s^+\pi ^0$$ and $$D_s^{*+}\gamma $$

Focusing on the description of cosmic evolution at late times, this study examines a generalized holographic dark energy (HDE) framework constructed via a polynomial expansion in the Hubble parameter, which includes contributions proportional to $$H^{2},$$ $$H^{4},$$ and $$H^{6},$$ introduced through a variable parameter within the standard holographic formula. The analysis is carried out in the context of a spatially flat Friedmann–Lemaître–Robertson–Walker (FLRW) Universe, consisting of non-interacting matter together with the HDE fluid. We obtain the full set of Friedmann equations to investigate cosmic evolution and then analyze the system to determine whether thermodynamic $$P{-}v$$ type phase transitions can occur.

Mexico

Miguel Cruz

Chile

Joaquín Housset

Samuel Lepe

Joel Saavedra

Francisco Tello-Ortiz

First-order phase transitions and cosmic evolution: thermodynamic approach to generalized holographic dark energy

We propose a three-zero texture for the down-quark mass matrix within a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> grand unified theory (GUT)-inspired Standard Model, enforced by a noninvertible selection rule originating from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="double-struck">Z</mi><mn>2</mn></msub></math> gauging of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi mathvariant="double-struck">Z</mi><mi>N</mi></msub></math> symmetries. Assuming <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> invariance at the high-energy scale, our framework solves the strong <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> problem while reproducing a realistic quark mass matrix. The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> symmetry is spontaneously broken down at an intermediate scale via complex vacuum expectation values of new scalar fields <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>η</mi><mi>i</mi></msub></math>, which generate the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> phase in the Cabibbo-Kobayashi-Maskawa matrix without inducing the quantum chromodynamics (QCD) <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mover accent="true"><mi>θ</mi><mo stretchy="false">¯</mo></mover></math> term. The present model incorporates three generations of matter, Higgs, and additional scalars with a common structure under the noninvertible symmetry, which may be naturally embedded into <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>O</mi><mo stretchy="false">(</mo><mn>10</mn><mo stretchy="false">)</mo></math> GUTs at high energies.

Japan

Tatsuo Kobayashi

Hajime Otsuka

Tsutomu T. Yanagida

Noninvertible symmetry as a solution to the strong <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> problem in a GUT-inspired standard model

Following a proposal for an experiment with sensitivity to an electric dipole moment (EDM) of the muon $\textit{d}$ of order 6 × 10 $\textit{e}$ cm, three to four orders of magnitude below the current bound, but still seven orders of magnitude above the current bound on the EDM of the electron $\textit{d}$ , we explore the discovery potential of such an experiment. Within the dimension-six CP violating operators of the Standard Model effective field theory (SMEFT), we identify two dipole operators where $\textit{d}$ has the strongest sensitivity, and four classes of four-fermion operators where it has the best sensitivity for regions of parameter space that are far from minimal flavor violation. We further consider three UV completions: vector-like leptons (VLLs), heavy vector boson with off-diagonal leptonic couplings, and two Higgs doublet model. For each, we identify the region in parameter space that will be uniquely explored by the proposed $\textit{d}$ experiment. In case of VLLs, we also find measurements of Γ($\textit{h}$ → $\textit{μμ}$) offer competitive sensitivity, highlighting the complementary role of collider observables. Generically, the potential reach is to $$ \mathcal{O} $$ (10 TeV) scale of new physics.

United Arab Emirates

Kuldeep Deka

Marta Losada

Israel

Yosef Nir

Chasing the muon EDM to constrain the SMEFT and UV models

We develop a Heisenberg-picture $\textit{kinematical}$ framework in which (i) time is treated as a quantum observable, admitting both a relational POVM construction for semibounded spectra and a fully self-adjoint realization on an enlarged (conjugate-energy) Hilbert space enabled by a gravitational conjugation symmetry $$\mathcal {C}_g$$ , and (ii) the generators of spacetime translations need not commute in curved backgrounds. The central postulate, $$[\,\hat{x}_\mu ,\hat{P}_\nu ]=\textrm{i}\hbar \,\hat{g}_{\mu \nu }(\hat{x})$$ , makes the spacetime metric a $\textit{metric operator}$ defined by the symmetrized commutator. Jacobi identities close the algebra and imply an operator form of metric compatibility; in a worked example we obtain $$[\,\hat{P}_0,\hat{P}_i]=2\textrm{i}\hbar \,N^2(t)\,H(t)\,\hat{P}_i$$ , which reduces to $$2\textrm{i}\hbar \,H\,\hat{P}_i$$ in cosmic-time gauge $$N=1$$ , exhibiting Hubble–controlled non-commuting “translations.” A key structural ingredient is the symmetry $$\mathcal {C}_g$$ : an antiunitary map that flips all translation generators, $$\hat{P}_\mu \!\rightarrow \!-\Theta \hat{P}_\mu \Theta ^{-1}$$ , while covariantly transforming the metric and Lorentz sectors, leaving the canonical commutators and the [$\textit{P}$, $\textit{P}$] algebra invariant. We discuss uncertainty relations and show how metric-operator fluctuations can rescale primordial amplitudes; an explicitly labeled $\textit{toy}$ propagation of such a rescaling to high-$\textit{z}$ halo abundances is given in Appendix $\textit{D}$.

Canada

Iran

Vahid Kamali

Quantum geometry from commutators: a Heisenberg-picture framework and a toy application to early structure

We address the equilibrium configurations and stability properties of anisotropic compact stars whose interior is described by a modified Chaplygin gas (MCG) equation of state in the framework of the regularized four-dimensional Einstein–Gauss–Bonnet (4DEGB) theory. Applying a quasi-local prescription for the pressure anisotropy, we derive the modified Tolman–Oppenheimer–Volkoff (TOV) equations and integrate them numerically over a large parameter space in the Gauss–Bonnet coupling $$\alpha $$ and the degree of anisotropy $$\beta $$ . We provide mass–radius sequences, mass-compactness, energy density, and pressure profiles, and perform a full stability analysis based on the turning-point criterion, the radial adiabatic index $$\gamma _r$$ , and the radial and transverse sound speeds $$v_r^2$$ and $$v_t^2$$ . Our results show that positive $$\alpha $$ and positive anisotropy $$(\beta > 0)$$ systematically increase the maximum mass and radius, enabling then configurations that exceed $$2\,M_\odot $$ while still obeying causality and the modified Buchdahl bound in 4DEGB gravity. A comparison with the latest astrophysical constraints (NICER, GW170817, GW190814, and massive-pulsar measurements) identifies regions of the $$(\alpha ,\beta )$$ parameter space that are observationally allowable. In conclusion, anisotropic dark-energy stars in 4DEGB gravity provide viable, observationally testable ultra-compact alternatives to normal neutron stars and black holes, and also potentially open rich avenues for further multi-messenger searches for higher-curvature effects.

India

Anirudh Pradhan

Thailand

Takol Tangphati

South Africa

Ayan Banerjee

Uzbekistan

Javlon Rayimbaev

Dark-energy anisotropic compact configurations in 4D Einstein–Gauss–Bonnet gravity: from structure to observational viability

We propose a novel, data-driven method for determining total charm cross sections in proton–proton collisions by extrapolating measured fiducial cross sections without assuming any particular fragmentation model. The recently observed charm fragmentation non-universality at the LHC experimentally establishes strongly increased baryon production fractions and correspondingly decreased meson production fractions compared to electron–positron collisions, with a very significant $$p_T$$ dependence. The novel method accounts for this non-universality and its $$p_T$$ -dependence through a data-driven extrapolation function called ddFONLL. Applied to $$D^0$$ production at 5 and 13 TeV, this approach yields total charm cross sections that fully incorporate the fragmentation non-universality and increase significantly compared to the previous measurements still based on fragmentation universality. The results are consistent with NNLO QCD predictions and enable direct comparisons free from fragmentation assumptions. We use this to evaluate the sensitivity of total cross-section measurements to parton distribution functions and the charm-quark mass. An outlook is given on the potential of further expanding the use of the ddFONLL method.

Germany

Hungary

Yewon Yang

Achim Geiser

Sven-Olaf Moch

Oleksandr Zenaiev

A novel phenomenological approach to total charm cross-section measurements at the LHC

We study the continuum limit of branched polymers (BPs) with loops coupled to Ising spins at the zero-temperature critical point. It is known that the continuum partition function can be represented by a Hermitian two-matrix model, and we propose a string field theory whose Dyson-Schwinger equation coincides with the loop equation of this continuum matrix model. By setting the matrix size to one, we analyze a convergent nonperturbative partition function expressed as a two-dimensional integral, and show that it satisfies a third-order linear differential equation. In contrast, in the absence of coupling to the critical Ising model, the continuum partition function of pure BPs with loops is known to satisfy the Airy equation. From the viewpoint of two-dimensional quantum gravity, we introduce a nonperturbative loop amplitude that serves as a solution to the Wheeler-DeWitt equation incorporating contributions from all genera. Furthermore, we demonstrate that the same Wheeler-DeWitt equation can also be derived through the stochastic quantization.

Denmark

Netherlands

Jan Ambjørn

Yukimura Izawa

Yuki Sato

Branched polymers with loops coupled to the critical Ising model

In the recent years, argon-based experiments looking for Dark Matter in the Universe have explored the non-standard scenario in which Dark Matter is made by low-mass Weakly Interacting Massive Particles, of mass in the range of 1–10 GeV instead of the canonical hundreds of GeV. Detecting such particles is challenging, as their expected signatures are nuclear recoils with energies below 10 keV, observable solely via ionization. This necessitates a precise understanding of the detector response in this energy regime, which remains incomplete for argon. To address this, the ReD experiment was developed within the framework of the DarkSide-20k Collaboration to produce and characterize few-keV nuclear recoils. A compact dual-phase argon Time Projection Chamber (TPC) was irradiated with neutrons from a $$^{252}$$ Cf source, to produce Ar recoils in the energy range of interest via (n,n’) elastic scattering. A downstream spectrometer composed of 18 plastic scintillators detected the neutrons scattered off Ar nuclei, enabling recoil energy reconstruction via two-body kinematics. The ionization yield $$Q_{y}$$ of argon, defined as the number of electrons produced per unit energy deposit, was measured in a model-independent way between 2 and 10 keV. These measurements extend direct experimental coverage well below the previous limit of approximately 7 keV. The results are consistent with existing data above 7 keV, while they indicate a higher $$Q_{y}$$ at lower energies.

Italy

P. Agnes

Poland

I. Ahmad

S. Albergo

Brazil

I. Albuquerque

M. Corona

M. Ave

B. Bottino

M. Cadeddu

A. Caminata

N. Canci

M. Caravati

L. Consiglio

S. Davini

L. Dias

Russia

G. Dolganov

G. Fiorillo

France

D. Franco

M. Gulino

T. Hessel

N. Kemmerich

M. Kimura

M. Kuźniak

M. La Commara

J. Machts

G. Matteucci

E. Santos

E. Nikoloudaki

V. Oleynikov

L. Pandola

R. Varona

N. Pino

S. Puglia

M. Rescigno

B. Costa

S. Sanfilippo

United States

A. Sung

C. Sunny

Y. Suvorov

R. Tartaglia

G. Testera

A. Tricomi

M. Wada

Y. Wang

R. Wojaczyński

P. Zakhary

Characterization of the ionization response of argon to nuclear recoils at the keV scale with the ReD experiment

We propose that the broad architecture of the renormalization group flow in quantum field theories is, at least in part, fixed by unitarity. The precise statement is summarized in the unitarity flow conjecture, which states that the nonlinear <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>S</mi></mrow></math>-matrix identities obtained by imposing unitarity imply those needed to derive the renormalization group equations. As a proof of principle, we verify this conjecture to all loops at the leading and subleading logarithmic order in the four-dimensional massless <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>λ</mi><msup><mrow><mi>ϕ</mi></mrow><mrow><mn>4</mn></mrow></msup></mrow></math> theory using on-shell techniques, without reference to any counterterms or Feynman diagrams.