Contents

JETP Letters

Vol. 123, No. 12, 2026

FIELDS, PARTICLES, AND NUCLEI

Study of K+ → π+π–π+γ Decay in the OKA Experiment

A. Artamonov, A. Gorin, Ye. Gushchin, S. Donskov, B. Zalikhanov, A. Inyakin, G. Kekelidze, V. Kolosov, A. Konoplyannikov, V. Kravtsov, Yu. Kudenko, A. Kulik, V. Kurshetsov, V. Lishin, V. Lysan, M. Medynskyi, A. Okhotnikov, V. Obraztsov, V. Polyakov, V. Rykalin, A. Sadovskiy, V. Samoilenko, S. Slabospitskiy, I. Tiurin, V. Uvarov, A. Filin, S. Filippov, G. Khaustov, S. Kholodenko, A. Khudyakov, M. Shapkin, and O. Yushchenko p. 803  abstract

OPTICS AND LASER PHYSICS

On Measurement of the Second-Order Coherence of Light–Matter Bose–Einstein Condensates with a Single Detector

I. V. Panyukov and E. S. Andrianov p. 808  abstract

OPTICS AND LASER PHYSICS

Criteria for the Formation of Laser-Induced Periodic Surface Structures in Phase-Change Materials under Femtosecond Irradiation

O. I. Sokolovskaya, D. V. Shuleiko, M. P. Smayev, Ya. S. Lebedeva, S. V. Zabotnov, L. A. Golovan, P. K. Kashkarov, and S. A. Kozyukhin p. 816  abstract

OPTICS AND LASER PHYSICS

Correlations of Optical Wave Phase Gradients in a Stratified Turbulent Atmosphere

A. V. Nemtseva and F. A. Starikov p. 824  abstract

OPTICS AND LASER PHYSICS

Dynamics of Photoinduced Lattice Heating and Electron–Phonon Relaxation in Gold Single Crystals According to Ultrafast Electron Diffraction Data

B. N. Mironov, D. G. Poydashev, S. A. Aseyev, and E. A. Ryabov p. 832  abstract

OPTICS AND LASER PHYSICS

Smith–Purcell Radiation from a Discrete Target Located on the Axis of a Hollow Electron Beam

D. Yu. Sergeeva and A. A. Tishchenko p. 838  abstract

PLASMA, HYDRO- AND GAS DYNAMICS

Effect of a Supercritical CO2 Microstructure on Clustering in the Process of Expansion into a Vacuum

T. A. Semenov, G. V. Mishakov, A. V. Lazarev, E. O. Epifanov, N. V. Minaev, and E. I. Mareev p. 843  abstract

CONDENSED MATTER

Stable Modes in a Magnon Bose–Einstein Condensate Self-Generator

Yu. M. Bunkov, P. M. Vetoshko, A. N. Kuzmichev, D. S. Novokreshchenov, and D. A. Samodelkin p. 851  abstract

CONDENSED MATTER

Two-Stage Coalescence of Droplets in the Confined Geometry of Hele–Shaw Cells

P. V. Dolganov and N. A. Spiridenko p. 857  abstract

METHODS OF PHYSICAL RESEARCH

Increasing the Modulation Instability Threshold in a Direct-Diode-Pumped Kerr-Lens Mode-Locked Ti:Sa Oscillator

K. E. Reznikov, A. O. Mavritskiy, M. N. Esaulkov, and A. V. Naumov p. 864  abstract

QUANTUM INFORMATICS

States Dressing Analysis in a Transmon–Transmon–Bus System

P. A. Gladilovich, R. A. Migdisov, A. V. Sabluk, P. S. Burtsev, N. N. Abramov, N. Yu. Rudenko, V. I. Chichkov, and N. A. Maleeva p. 873  abstract