We investigate the frame dependence of distribution functions within the framework of generalized chiral kinetic theory. Based on the derived transformation rules governing the choice of frame, we analytically obtain the global equilibrium solutions in the presence of vorticity and electromagnetic fields. Our results show that, under the assumption of varying electromagnetic fields, these equilibrium solutions can be uniquely determined.

China

Shu-Xiang Ma

Jian-Hua Gao

Frame dependence in generalized chiral kinetic theory * Supported in part by the National Natural Science Foundation of China (12575147, 12321005, 12175123)

Within a Bethe-Salpeter model, we investigate the production of possible <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mi>s</mi></msub><msub><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mi>s</mi></msub></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><msub><mi>X</mi><mrow><mi>s</mi><mover accent="true"><mi>s</mi><mo stretchy="false">¯</mo></mover></mrow></msub><mo stretchy="false">)</mo></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover></math> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><msub><mi>X</mi><mrow><mi>q</mi><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover></mrow></msub><mo stretchy="false">)</mo></math> bound states in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decays. The bound state properties of the two heavy meson systems are studied in the one-boson-exchange kernel, and the resulting normalized Bethe-Salpeter wave functions are used to calculate the branching fractions of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msub><mi>X</mi><mrow><mi>s</mi><mover accent="true"><mi>s</mi><mo stretchy="false">¯</mo></mover></mrow></msub><msup><mi>K</mi><mo>+</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>B</mi><mo>+</mo></msup><mo stretchy="false">→</mo><msub><mi>X</mi><mrow><mi>q</mi><mover accent="true"><mi>q</mi><mo stretchy="false">¯</mo></mover></mrow></msub><msup><mi>K</mi><mo>+</mo></msup></math>. We find that bound-state solutions for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover></math> system exist for all three coupling sets considered, whereas the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mi>s</mi></msub><msub><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mi>s</mi></msub></math> system supports a bound state solution only in a restricted parameter region. The predicted branching fractions are in the ranges of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1.09</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup><mi>–</mi><mn>20.06</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math> for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mi>s</mi></msub><msub><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mi>s</mi></msub></math> bound state and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1.56</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>6</mn></mrow></msup><mi>–</mi><mn>4.14</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math> for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover></math> bound state. In particular, if <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>X</mi><mo stretchy="false">(</mo><mn>3915</mn><mo stretchy="false">)</mo></math> is interpreted as a predominantly <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mi>s</mi></msub><msub><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mi>s</mi></msub></math> bound state, its production branching fraction in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decay is found to be <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5.79</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math>.

Zhen-Yang Wang

Jing-Juan Qi

Zhen-Hua Zhang

Xin-Heng Guo

Production of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>D</mi><mi>s</mi></msub><msub><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover><mi>s</mi></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>D</mi><mover accent="true"><mi>D</mi><mo stretchy="false">¯</mo></mover></math> bound states in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>B</mi></math> decays within the Bethe-Salpeter framework

Quarks and gluons, as quantum particles, are subject to various effects that go beyond the naive parton picture and are not captured by ordinary parton densities. In this work, we investigate the twist-three parton distribution functions, which encode quantum interference between quark-gluon-quark states, and for the first time, determine them directly from experimental data. The analysis combines observables described by collinear and transverse-momentum–dependent factorization theorems within a unified global fit, incorporating a complete leading-order QCD evolution at the twist-three level. The extracted distributions reveal clear flavor-dependent patterns and are distinct from zero at a statistically significant level (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>2</mn><mo>−</mo><mn>3</mn><mi>σ</mi></mrow></math>). These findings provide the first quantitative evidence for quark-gluon-quark correlations within the proton, revealing its genuinely quantum nature and opening a new direction for precision studies of partonic correlations.

Spain

Alexey Vladimirov

Guillermo Portela

Germany

Italy

Simone Rodini

Determination of Quark-Gluon-Quark Interference within the Proton

A search for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> violation in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mrow><msup><mrow><mover accent="true"><mrow><mi>B</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mn>0</mn></mrow></msup></mrow><mo stretchy="false">→</mo><mrow><mrow><msup><mrow><mover accent="true"><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mo>*</mo><mn>0</mn></mrow></msup></mrow><msup><mrow><mi>μ</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>μ</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></mrow></math> decay is performed using proton-proton collision data collected by the LHCb experiment during Run 1 and Run 2, corresponding to an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>8.4</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. The analysis exploits the full angular distribution of the decay, providing sensitivity to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math>-violating effects in both vector and axial-vector contributions to this flavor-changing neutral-current process. The complex Wilson coefficients are determined within the weak effective theory through an unbinned maximum-likelihood fit to the angular observables, incorporating nonlocal hadronic amplitudes across the full dimuon mass spectrum. The precision of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math>-violation observables is improved by an order of magnitude relative to previous measurements, with the imaginary parts of the Wilson coefficients now determined more precisely than the real parts. No significant <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>C</mi><mi>P</mi></math> violation is observed, and the results are consistent with the standard model.

Netherlands

R. Aaij

United States

M. Abdelfatah

United Kingdom

A.S.W. Abdelmotteleb

Switzerland

C. Abellan Beteta

F. Abudinén

T. Ackernley

A.A. Adefisoye

B. Adeva

M. Adinolfi

Poland

P. Adlarson

France

C. Agapopoulou

C.A. Aidala

S. Akar

K. Akiba

P. Albicocco

J. Albrecht

R. Aleksiejunas

CERN

F. Alessio

P. Alvarez Cartelle

Brazil

S. Amato

J.L. Amey

Y. Amhis

L. An

L. Anderlini

M. Andersson

P. Andreola

M. Andreotti

S. Andres Estrada

A. Anelli

D. Ao

C. Arata

F. Archilli

Z. Areg

M. Argenton

Costa Rica

S. Arguedas Cuendis

L. Arnone

M. Artuso

E. Aslanides

R. Ataíde Da Silva

M. Atzeni

B. Audurier

J.A. Authier

D. Bacher

I. Bachiller Perea

S. Bachmann

M. Bachmayer

J.J. Back

Z.B. Bai

V. Balagura

A. Balboni

W. Baldini

Z. Baldwin

L. Balzani

H. Bao

J. Baptista de Souza Leite

C. Barbero Pretel

M. Barbetti

I.R. Barbosa

R.J. Barlow

M. Barnyakov

S. Baron

S. Barsuk

W. Barter

J. Bartz

S. Bashir

B. Batsukh

P.B. Battista

A. Bavarchee

A. Bay

A. Beck

M. Becker

F. Bedeschi

I.B. Bediaga

N.A. Behling

S. Belin

A. Bellavista

I. Belov

I. Belyaev

G. Bencivenni

E. Ben-Haim

R. Bernet

A. Bertolin

F. Betti

J. Bex

O. Bezshyyko

S. Bhattacharya

M.S. Bieker

N.V. Biesuz

A. Biolchini

M. Birch

F.C.R. Bishop

A. Bitadze

A. Bizzeti

T. Blake

F. Blanc

J.E. Blank

S. Blusk

J.A. Boelhauve

O. Boente Garcia

T. Boettcher

<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>C</mi><mi>P</mi></mrow></math> Violation Analysis of Local and Nonlocal Amplitudes in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mover accent="true"><mrow><mi>B</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mn>0</mn></mrow></msup><mo stretchy="false">→</mo><msup><mrow><mover accent="true"><mrow><mi>K</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mrow><mi>μ</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>μ</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> Decay

We systematically investigate the scaling properties of the transverse momentum spectra for pions, kaons, and protons in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Au</mi><mo>+</mo><mi>Au</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>7.7</mn></mrow></math>, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV, as well as in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi mathvariant="normal">U</mi><mo>+</mo><mi mathvariant="normal">U</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>193</mn><mspace width="0.16em"></mspace><mi>GeV</mi></mrow></math>, across different centrality classes, using experimental data from the collaborations at the Relativistic Heavy Ion Collider (RHIC). Universal scaling emerges when the particle transverse momentum spectra are scaled by global physical quantities, i.e., the average total particle multiplicity and mean transverse momentum, confirming recent scaling findings from the data at the Large Hadron Collider (LHC) by the ExTrEMe Collaboration. The scaling behavior breaks down in the high <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>p</mi><mi mathvariant="normal">T</mi></msub></math> region and in peripheral collisions. We provide a natural explanation for these observations in the framework of a blast-wave-type model built upon the Cooper-Frye formula. Furthermore, we demonstrate the equivalence between the scaling found by the ExTrEMe Collaboration and the Hwa-Yang scaling, which was proposed two decades ago.

Xi-Yao Guo

Hua Zheng

Wen-Chao Zhang

Li-Lin Zhu

Xing-Quan Liu

Zhi-Guang Tan

Dai-Mei Zhou

Ben-Hao Sa

Deciphering the universal scaling of particle transverse momentum spectra in heavy-ion collisions

In this work, we systematically assess the performance of a new method from [H. Shah et al., <a href="http://dx.doi.org/10.1103/cbwj-4jfl">Phys. Rev. C 113, L012201 (2026)</a>] for locating the QCD critical point using constant-entropy contours by testing it against various effective QCD approaches. We demonstrate that, while the method yields spurious critical points in purely hadronic models (HRG) due to nonparabolic contour behavior at low temperatures (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mo>≲</mo><mn>120</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>), it accurately reproduces the critical point location in frameworks that feature a genuine phase transition and benchmarked against lattice QCD, such as holographic Einstein-Maxwell-dilaton, and functional QCD approaches. Building on our previous determination of constant entropy contours using lattice data, we extend that analysis to construct a complete lattice-based equation of state (EoS) at finite density, which features a critical point at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">(</mo><mi>T</mi><mo>,</mo><msub><mi>μ</mi><mi>B</mi></msub><mo stretchy="false">)</mo><mo>≈</mo><mo stretchy="false">(</mo><mn>114</mn><mo>,</mo><mn>602</mn><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>. By integrating the extrapolated entropy density with respect to temperature, we reconstruct the pressure, baryon density, susceptibility, and speed of sound in the critical region, and analyze the focusing behavior of isentropic trajectories in the vicinity of the critical point.

Hitansh Shah

Mauricio Hippert

Jorge Noronha

Claudia Ratti

Volodymyr Vovchenko

Lattice-based equation of state with a critical point from constant entropy contours and its comparison to effective QCD approaches

We study in the bottom-up framework the possibility to generate the quark mass hierarchies without severe fine-tuning, the quark mixing and CP-violation (CPV) in a flavour model with $$S^\prime _4$$ modular symmetry having minimal number of parameters. The model is considered in the vicinity of the fixed point $$\tau _\text {T}= i\infty $$ , $$\tau _\text {vev} \sim \tau _\text {T}$$ , $$\tau _\text {vev}$$ being the vacuum expectation value (VEV) of the modulus $$\tau $$ , which allows to explain the hierarchies of the quark masses. The ten quark observables are described effectively by nine real parameters. The CP-symmetry is broken explicitly since, as is well known, reproducing the observed CPV in the quark sector in the case of spontaneous breaking of CP-symmetry by $$\tau _\text {vev}$$ is highly problematic in the class of minimal modular quark flavour models (explaining the quark mass hierarchies without fine-tuning) of the type we consider. We perform a statistical analysis of the model and show that it is phenomenologically viable and consistent, in particular, with the “inclusive” decay data on the $$|V_{ub}|$$ and $$|V_{cb}|$$ elements of the CKM matrix and, in the case of a very high scale of supersymmetry breaking, with the current “average” experimental values of $$|V_{ub}|$$ and $$|V_{cb}|$$ .

Japan

S. Petcov

M. Tanimoto

$$S^\prime _4$$ quark flavour model in the vicinity of the fixed point $$\tau = i\infty $$

We present an investigation into beam steering and radiation emission by sub-GeV electrons traversing a bent silicon crystal. Using 855, 600, and 300 MeV electron beams at the Mainz Microtron (MAMI), we explored orientational coherent effects in a 15- $$\upmu $$ m-thick silicon crystal bent along the (111) planes. Combined experimental and simulation analyses enabled the classification and quantitative assessment of the contributions from channeling, dechanneling, rechanneling, and volume capture to both beam deflection and radiation emission. Crystal steering remained effective even at 300 MeV, with measured channeling efficiencies exceeding 50%, a record at such low energies. Channeling and volume reflection enhanced radiation emission by up to a factor of six compared to the misaligned orientation, highlighting strong orientational coherence effects in the sub-GeV regime. These findings confirm the feasibility of using bent crystals for efficient beam manipulation and high-intensity photon generation at low energies, supporting the development of novel light sources and beam control strategies at accelerator facilities operating in this energy range.

R. Negrello

M. Romagnoni

A. Sytov

N. Canale

D. De Salvador

P. Fedeli

V. Guidi

V. Haurylavets

P. Klag

W. Lauth

L. Malagutti

A. Mazzolari

G. Paternó

F. Sgarbossa

M. Soldani

V. Tikhomirov

D. Valzani

L. Bandiera

Beam steering and radiation generation of electrons in bent crystals in the sub-GeV domain

Within the framework of light-front holographic QCD, where transverse confinement is inherently realized through holography, the structure and mass spectrum of the light scalar meson $$K_0^{*}(1430)$$ are investigated by employing the invariant mass ansatz and enhancing the model with a longitudinal confinement potential (specifically, the ’t Hooft equation and the analytically solvable LMZV potential). The combined transverse and longitudinal confinement dynamics lead to more reliable calculations of key observables, including decay constants, parton distribution function, $$\xi $$ -moments, and twist-2 and twist-3 distribution amplitudes. Transition form factors for the semileptonic decay $$B \rightarrow K_0^{*} \ell ^+ \ell ^-$$ are computed from these amplitudes, yielding predictions for differential branching ratios and longitudinal lepton polarization asymmetries as functions of $$q^2$$ . The results are compared with other theoretical models, offering valuable insights into the non-perturbative dynamics of QCD. The predicted observables provide theoretically motivated benchmarks for future experimental investigations of $$B\rightarrow K_0^*(1430)\ell ^+\ell ^-$$ decays at LHCb and Belle II.

Iran

O. Hemmati

R. Khosravi

Holographic study of the scalar meson $$K_0^*(1430)$$ with dynamical longitudinal confinement

The Dark Energy Spectroscopic Instrument (DESI) measurements of baryon acoustic oscillations (BAO) have recently shown a mild preference for dynamical dark energy over the standard $$\mathrm \Lambda $$ CDM model. In this paper, we analyze the $$w_0w_a$$ CDM model using DESI BAO DR2, Pantheon+ SNe Ia, and Planck 2018 CMB distance prior data. To examine how different parts of the data affect the apparent deviation from $$\mathrm \Lambda $$ CDM, we adopt two complementary redshift-cut strategies, dividing the dataset into $$z<z_\textrm{cut}$$ and $$z>z_\textrm{cut}$$ subsamples. We find that the most noticeable shifts occur when BAO and SNe Ia data in the redshift range $$z\sim 0.4$$ –0.8 are included, reaching a significance of about $$\sim 2\sigma $$ . Within this framework, the inclusion of higher-redshift measurements progressively weakens this deviation and brings the constraints closer to the $$\mathrm \Lambda $$ CDM expectation. Moreover, the information criteria show no statistically significant preference between the $$w_0w_a$$ CDM and $$\mathrm \Lambda $$ CDM models, while the Bayesian information criterion consistently favors the $$\mathrm \Lambda $$ CDM model. In addition, a parameter-shift consistency test reveals no statistically significant tension between complementary redshift subsamples. Within the DESI BAO DR2, Pantheon+, and CMB distance prior framework adopted here, these results do not provide statistically robust evidence favoring the $$w_0w_a$$ CDM model over $$\mathrm \Lambda $$ CDM. They instead indicate that the apparent parameter shifts under different redshift cuts may be affected by statistical fluctuations and by the limited precision and number of datapoints in the current subsamples. Our analysis provides a complementary redshift-dependent diagnostic for assessing how the inferred cosmological constraints vary under different redshift selections.

Jie Zheng

Da-Chun Qiang

Zhi-Qiang You

Darshan Kumar

Revisiting the equation of state of dark energy from DESI BAO with SNe Ia and CMB