Contents

Bulletin of the Lebedev Physics Institute

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Vol. 52, No. 5, 2025

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Low-Energy Background Events in the Horizon-T Experiment at the Tien Shan High-Altitude Scientific Station of the Lebedev Physical Institute

M. I. Vildanova, A. M. Anokhina, V. S. Aseikin, K. A. Baigarin, E. A. Beisembaeva, V. V. Zhukov, V. A. Ryabov, M. A. Samoilov, T. Kh. Sadykov, and S. B. Shaulov p. 191  abstract

Well-Type Xenon Gamma-Ray Spectrometer

R. R. Egorov, V. V. Dmitrenko, V. M. Grachev, A. I. Madzhidov, A. E. Shustov, N. M. Sveshnikov, K. F. Vlasik, S. E. Ulin, and Z. M. Uteshev p. 200  abstract

Synthesis of CaRbFe₄As₄ and EuCsFe₄As₄ Stoichiometric Superconductors by Mechanical Alloying

A. S. Medvedev, A. D. Denishchenko, V. A. Vlasenko, and K. S. Pervakov p. 208  abstract

On the Parameters of the Cathode Plasma Arising during the Breakdown of Millimeter Air Gaps at Low Pressures

E. V. Parkevich, A. I. Khirianova, and K. V. Shpakov p. 213  abstract

Initial Stage of an Arc Discharge in Vacuum and Ectonic Model

A. N. Dolgov, N. A. Klyachin, A. A. Rodionov, F. K. Gasratov, and A. V. Oginov p. 219  abstract

On the K⁺ → π⁰π⁰π⁰e⁺ν Decay

E. K. Karkaryan, K. V. Kiselev, V. F. Obraztsov, I. V. Surkov, and M. I. Vysotsky p. 228  abstract

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