Contents

Astronomy Letters

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Vol. 47, No. 6, 2021

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Constructing a Stäckel Model of the Galaxy: Solving the Problem of Whether the Vertical Density Distribution Is Realistic

A. O. Gromov and I. I. Nikiforov p. 357  abstract

Change in the Orbital Period of a Binary System Due to an Outburst in a Windy Accretion Disk

A. L. Avakyan, G. V. Lipunova, K. L. Malanchev, and N. I. Shakura p. 377  abstract

Study of the X-ray Pulsar XTE J1946+274 with NuSTAR

A. S. Gorban, S. V. Molkov, S. S. Tsygankov, and A. A. Lutovinov p. 390  abstract

The First Light Curve Solutions and Period Study of BQ Ari

A. Poro, F. Davoudi, F. Alicavus, S. Khakpash, E. M. Esmer, O. Basturk, E. Lashgari, J. Rahimi, Y. Aladag, N. Aksaker, A. Boudesh, M. Ghanbarzadehchaleshtori, A. Akyuz, S. Modarres, A. Sojoudizadeh, M. Tekes, and A. Solmaz p. 402  abstract

Effects of Metallicity on Mode Switching in Cepheids

Yu. A. Fadeyev p. 411  abstract

Search for Evolutionary Changes in the Period of the Classical Cepheid CE Pup

L. N. Berdnikov p. 420  abstract

Search for Evolutionary Changes in the Periods of the Double-Mode Cepheid AS Cas

L. N. Berdnikov, A. A. Belinskii, E. N. Pastukhova, M. A. Burlak, N. P. Ikonnikova, E. O. Mishin, and N. I. Shatskii p. 430  abstract

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