Contents

Astronomy Letters

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Vol. 51, No. 1, 2025

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SRG/ART-XC Discovery of Pulsations from RX J0535.0-6700: Another X-ray Pulsar in the LMC

I. A. Mereminskiy, A. S. Gorban, Yu. S. Klein, E. A. Ushakova, A. N. Semena, A. A. Lutovinov, A. Yu. Tkachenko, and S. V. Molkov p. 1  abstract

Non-LTE Abundance Analysis of Main-Sequence A–B Stars. III. Normal-Star Criteria

A. M. Romanovskaya, T. A. Ryabchikova, L. I. Mashonkina, T. M. Sitnova, and N. Serebryakova p. 9  abstract

Elusive Helium Stars in the Gap between Subdwarfs and Wolf–Rayet Stars II. Nonlinear Pulsations of Stripped Helium Stars

Yu. A. Fadeyev, A. G. Kuranov, and L. R. Yungelson p. 25  abstract

To the Origin of the Fast X-ray Precursors of Solar Flares

V. V. Zaitsev, and A. V. Stepanov p. 34  abstract

A Method for Estimating the Spatial Period of Energy Release in Solar Flares II

L. S. Ledentsov p. 38  abstract

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