Vol. 123, No. 2, 2026

JETP Letters

FIELDS, PARTICLES, AND NUCLEI

Correction to CP-Asymmetry in \(\Upsilon {\text{(}}4S{\text{)}}\) Decays Due to the Admixture of \({{B}^{0}}{{\bar {B}}^{0}}\) in a C-Even State

N. A. Panchenko and S. I. Godunov p. 67 abstract

ASTROPHYSICS, SPACE PHYSICS, COSMOLOGY, AND GRAVITY

Testing New-Physics Scenarios with the Combined LHAASO and Carpet-3 Fluence Spectrum of GRB 221009A: Axion-Like Particles and Lorentz-Invariance Violation

P. S. Satunin and S. V. Troitsky p. 73 abstract

Search for Ultraviolet Signals from Fast Radio Bursts

M. S. Pshirkov and I. V. Tyurin p. 80 abstract

OPTICS AND LASER PHYSICS

Design Features of Optical Diffraction Neural Networks

A. V. Konovalova, A. A. Popkova, T. G. Baluian, and A. A. Fedyanin p. 85 abstract

Numerical Simulation of Light Structures in Bulk Epsilon-Near-Zero Media with Kerr Nonlinearity

V. P. Ruban p. 93 abstract

CONDENSED MATTER

Surface Axionic Magnon–Polaritons in Two-Dimensional Antiferromagnets

A. K. Zvezdin, K. A. Zvezdin, and A. P. Pyatakov p. 100 abstract

Anisotropy of the Electron Mobility of Two-Dimensional Biphenylene Structures

V. L. Katkov and V. A. Osipov p. 106 abstract

On the Validity of the One-Dimensional Description for Ring Polariton Bose–Einstein Condensates

K. D. Dyad’kin, M. A. Posazhenkov, and N. S. Voronova p. 113 abstract

Permanent Bose–Einstein Condensate

Yu. M. Bunkov, P. M. Vetoshko, G. A. Knyazev, A. N. Kuzmichev, and D. A. Samodelkin p. 119 abstract

Permittivity of Antiferromagnetic Multiferroics with a Cycloidal Spin Order in the Presence of the Magnetoelectric Effect Related to a Collinear Spin Component

P. Andreev p. 124 abstract

METHODS OF PHYSICAL RESEARCH

Experimental Investigation of Acoustic Kerker Effect in Labyrinthine Resonators