<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE root>
<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="other" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Astronomy Reports</journal-id><journal-title-group><journal-title xml:lang="en">Astronomy Reports</journal-title><trans-title-group xml:lang="ru"><trans-title>Астрономический журнал</trans-title></trans-title-group></journal-title-group><issn publication-format="print">0004-6299</issn><issn publication-format="electronic">3034-5170</issn><publisher><publisher-name xml:lang="en">The Russian Academy of Sciences</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">647577</article-id><article-id pub-id-type="doi">10.31857/S0004629923090086</article-id><article-id pub-id-type="edn">HSIWCM</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Articles</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>СТАТЬИ</subject></subj-group><subj-group subj-group-type="article-type"><subject></subject></subj-group></article-categories><title-group><article-title xml:lang="en">PECULIARITIES OF LONG-TERM SPOT ACTIVITY OF SOME LATE SPECTRAL-TYPE STARS</article-title><trans-title-group xml:lang="ru"><trans-title>Особенности долговременной пятенной активности ряда звезд поздних спектральных классов</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kozhevnikova</surname><given-names>A. V.</given-names></name><name xml:lang="ru"><surname>Кожевникова</surname><given-names>А. В.</given-names></name></name-alternatives><email>alla.kozhevnikova@urfu.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Alekseev</surname><given-names>I. Yu.</given-names></name><name xml:lang="ru"><surname>Алексеев</surname><given-names>И. Ю.</given-names></name></name-alternatives><email>alla.kozhevnikova@urfu.ru</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kozhevnikov</surname><given-names>V. P.</given-names></name><name xml:lang="ru"><surname>Кожевников</surname><given-names>В. П.</given-names></name></name-alternatives><email>alla.kozhevnikova@urfu.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Ural Federal University named after the first President of Russia B.N. Yeltsin</institution></aff><aff><institution xml:lang="ru">Уральский федеральный университет им. Первого президента России Б.Н. Ельцина</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Research Institute “Crimean Astrophysical Observatory”</institution></aff><aff><institution xml:lang="ru">Научно-исследовательский институт “Крымская астрофизическая обсерватория”</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2023-09-01" publication-format="electronic"><day>01</day><month>09</month><year>2023</year></pub-date><volume>100</volume><issue>9</issue><fpage>811</fpage><lpage>819</lpage><history><date date-type="received" iso-8601-date="2025-01-28"><day>28</day><month>01</month><year>2025</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2023, А.В. Кожевникова, И.Ю. Алексеев, В.П. Кожевников</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2023, А.В. Кожевникова, И.Ю. Алексеев, В.П. Кожевников</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="en">А.В. Кожевникова, И.Ю. Алексеев, В.П. Кожевников</copyright-holder><copyright-holder xml:lang="ru">А.В. Кожевникова, И.Ю. Алексеев, В.П. Кожевников</copyright-holder></permissions><self-uri xlink:href="https://journals.eco-vector.com/0004-6299/article/view/647577">https://journals.eco-vector.com/0004-6299/article/view/647577</self-uri><abstract xml:lang="en"><p id="idm45257551483952">We present an analysis of long-term photometric observations of several dozen chromospherically active stars with solar-type activity (both from our own observations and from data available in the literature). The distribution of cold photospheric spots has been modeled based on a zonal model – several hundred models have been obtained. It has been found that the majority of stars have spots located at middle and moderate latitudes, the maximum spot areas can occupy from 7 to 58% of the star’s surface. It is shown that for some stars we can suspect the drift of spots in latitude, both towards the equator and towards the pole. However, the speed of such a drift is several times lower than that of sunspots. The presence of stellar activity cycles in 15 stars was revealed: cycles last from 3 to 28 years and expressed in changes in the brightness of the system, as well as in changes in the total spottedness of the star. The paper is based on a talk presented at the astrophysical memorial seminar “Novelties in Understanding the Evolution of Binary Stars”, dedicated to the 90th anniversary of Professor M.A. Svechnikov.</p></abstract><trans-abstract xml:lang="ru"><p id="idm45257551481840">В работе представлен анализ многолетних фотометрических наблюдений нескольких десятков хромосферно-активных звезд, обладающих активностью солнечного типа (как по нашим собственным наблюдениям, так и по имеющимся в литературе данным). Выполнено моделирование распределения холодных фотосферных пятен на основе зональной модели – получено несколько сотен моделей. Получено, что у большинства звезд пятна расположены на средних и умеренных широтах, максимальные площади пятен могут занимать от 7 до 58% поверхности звезды. Показано, что у ряда звезд можно заподозрить дрейф пятен по широте, как в сторону экватора, так и в сторону полюса, однако скорость такого дрейфа ниже в несколько раз, чем у солнечных пятен. Выявлено наличие циклов звездной активности у 15 звезд длительностью от 3 до 28 лет, выраженных в изменениях блеска системы, а также в изменениях общей запятненности звезды. Статья основана на докладе, сделанном на астрофизическом мемориальном семинаре “Новое в понимании эволюции двойных звезд”, приуроченном к 90-летию профессора М.А. Свечникова.</p></trans-abstract><kwd-group xml:lang="en"><kwd>variable stars</kwd><kwd>stellar activity</kwd><kwd>star spots</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>переменные звезды</kwd><kwd>звездная активность</kwd><kwd>звездные пятна</kwd></kwd-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>A. S. Brun and M. K. Browning, Liv. Rev. in Sol. Phys. 14, 133 (2017).</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>M. M. Katsova, L. L. Kitchatinov, D. Moss, K. Oláh, and D. D. Sokoloff, Astron. Rep. 62, 513 (2018).</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>V. N. Obridko, M. M. Katsova, and D. D. Sokoloff, Monthly Not. Roy. Astron. Soc. 516, 1251 (2022).</mixed-citation></ref><ref id="B4"><label>4.</label><mixed-citation>K. G. Strassmeier, Astron. and Astrophys. Rev. 17, 308 (2009).</mixed-citation></ref><ref id="B5"><label>5.</label><mixed-citation>S. V. Berdyugina, Liv. Rev. in Solar Phys. 2, 1 (2005).</mixed-citation></ref><ref id="B6"><label>6.</label><mixed-citation>Р. Е. Гершберг, Активность солнечного типа звезд главной последовательности (Одесса: АстроПринт, 2002).</mixed-citation></ref><ref id="B7"><label>7.</label><mixed-citation>А. В. Кожевникова, В. П. Кожевников, И. Ю. Алексеев, И. А. Юшков, А. А. Дорогов, Астрон. журн. 89, 318 (2012).</mixed-citation></ref><ref id="B8"><label>8.</label><mixed-citation>А. В. Кожевникова, И. Ю. Алексеев, Астрон. журн. 92, 818 (2015).</mixed-citation></ref><ref id="B9"><label>9.</label><mixed-citation>I. Yu. Alekseev and A. V. Kozhevnikova, Astron. Rep. 62, 396 (2018).</mixed-citation></ref><ref id="B10"><label>10.</label><mixed-citation>M. Zeilik, S. Gordon, E. Juderlund, et al., Astrophys. J. 421, 303 (1994).</mixed-citation></ref><ref id="B11"><label>11.</label><mixed-citation>S. A. Naftilan and E. F. Milone, Astron. J. 84, 1218 (1979).</mixed-citation></ref><ref id="B12"><label>12.</label><mixed-citation>C. Lazaro and M. J. Arevalo, Astron. J. 113, 2283 (1997).</mixed-citation></ref><ref id="B13"><label>13.</label><mixed-citation>M. Afsar, P. A. Heckert, and C. Ibanoglu, Astron. and Astrophys. 420, 595 (2004).</mixed-citation></ref><ref id="B14"><label>14.</label><mixed-citation>S. Messina and E. F. Guinan, Astron. and Astrophys. 393, 225 (2002).</mixed-citation></ref><ref id="B15"><label>15.</label><mixed-citation>S. Messina and E. F. Guinan, Astron. and Astrophys. 409, 1017 (2003).</mixed-citation></ref><ref id="B16"><label>16.</label><mixed-citation>S. P. Jarvinen, S. V. Berdyugina, and K. G. Strassmeier, Astron. and Astrophys. 440, 735 (2005).</mixed-citation></ref><ref id="B17"><label>17.</label><mixed-citation>K. G. Strassmeier and J. B. Rice, Astron. and Astrophys. 330, 685 (1998).</mixed-citation></ref><ref id="B18"><label>18.</label><mixed-citation>J. D. Dorren, M. Güdel, and E. F. Guinan, Astrophys. J. 448, 431 (1995).</mixed-citation></ref><ref id="B19"><label>19.</label><mixed-citation>G. Cutispoto, S. Messina, and M. Rodonó, Astron. and Astrophys. 400, 659 (2003).</mixed-citation></ref><ref id="B20"><label>20.</label><mixed-citation>A. Udalski and E. H. Geyer, Inform. Bull. Var. Stars. 2525 (1984).</mixed-citation></ref><ref id="B21"><label>21.</label><mixed-citation>A. Udalski and E. H. Geyer, Inform. Bull. Var. Stars. 2691 (1985).</mixed-citation></ref><ref id="B22"><label>22.</label><mixed-citation>G. Cutispoto, Astron. and Astrophys. Suppl. Ser. 131, 321 (1998).</mixed-citation></ref><ref id="B23"><label>23.</label><mixed-citation>S. V. Berdyugina, J. Pelt, and I. Tuominen, Astron. and Astrophys. 394, 505 (2002).</mixed-citation></ref><ref id="B24"><label>24.</label><mixed-citation>S. L. Baliunas, R. A. Donahue, W. H. Soon, et al., Astrophys. J. 438, 269 (1995).</mixed-citation></ref><ref id="B25"><label>25.</label><mixed-citation>S. Messina, E. F. Guinan, A. F. Lanza, and C. Ambruster, Astron. and Astrophys. 347, 249 (1999).</mixed-citation></ref><ref id="B26"><label>26.</label><mixed-citation>G. W. Lockwood, B. A. Skiff, G. W. Henry, S. M. Henry, R. R. Radick, et al., Astrophys. J. Suppl. Ser. 171, 260 (2007).</mixed-citation></ref><ref id="B27"><label>27.</label><mixed-citation>T. Lloyd-Evans and M. C. J. Koen, South. Afr. Astron. Obs. Circ. 11, 21 (1987).</mixed-citation></ref><ref id="B28"><label>28.</label><mixed-citation>G. Cutispoto, S. Messina, M. Rodonó, Astron. and Astrophys. 367, 810 (2001).</mixed-citation></ref><ref id="B29"><label>29.</label><mixed-citation>И. Ю. Алексеев, Изв. Крым. Астрофиз. Обс. 104, 272 (2008).</mixed-citation></ref><ref id="B30"><label>30.</label><mixed-citation>И. Ю. Алексеев, Р. Е. Гершберг, Астрон. журн. 73, 589 (1996).</mixed-citation></ref><ref id="B31"><label>31.</label><mixed-citation>K. Olah, Astrophys. and Space Science 304, 1–4, 145 (2006).</mixed-citation></ref><ref id="B32"><label>32.</label><mixed-citation>И. Ю. Алексеев, Запятненные звезды малых масс (Одесса: АстроПринт, 2001).</mixed-citation></ref><ref id="B33"><label>33.</label><mixed-citation>D. P. Kjurkchieva, D. V. Marchev, and W. Ogloza, Astron. and Astrophys. 400, 623 (2003).</mixed-citation></ref><ref id="B34"><label>34.</label><mixed-citation>D. P. Kjurkchieva, D. V. Marchev, P. A. Heckert, and C. A. Shower, Astron. and Astrophys. 424, 993 (2004).</mixed-citation></ref><ref id="B35"><label>35.</label><mixed-citation>M. Zeilik, M. Ledlow, M. Rhodes, et al., Astrophys. J. 354, 352 (1990).</mixed-citation></ref><ref id="B36"><label>36.</label><mixed-citation>D. Kjurkchieva, D. Marchev, and W. Ogloza, Astron. and Astrophys. 415, 231 (2004).</mixed-citation></ref><ref id="B37"><label>37.</label><mixed-citation>E. Budding and M. Zeilik, Astrophys. J. 319, 827 (1987).</mixed-citation></ref><ref id="B38"><label>38.</label><mixed-citation>P. Vivekananda Rao, M. B. R. Sarma, and B. V. N. S. Praksa Rao, J. Astrophys. Astron. 12, 225 (1991).</mixed-citation></ref><ref id="B39"><label>39.</label><mixed-citation>I. Yu. Alekseev and O. V. Kozlova, Astron. and Astrophys. 396, 203 (2003).</mixed-citation></ref><ref id="B40"><label>40.</label><mixed-citation>S. V. Berdyugina, A. V. Berdyugin, I. V. Ilyin, and I. Tuominen, Astron. and Astrophys. 360, 272 (2000).</mixed-citation></ref><ref id="B41"><label>41.</label><mixed-citation>S. V. Berdyugina, I. V. Berdyugin, I. V. Ilyin, and I. Tuominen, Astron. and Astrophys. 350, 626 (1999).</mixed-citation></ref><ref id="B42"><label>42.</label><mixed-citation>S. S. Vogt, A. Hatzes, A. Misch, and M. Kürster, Astrophys. J. Supp. 121, 547 (1999).</mixed-citation></ref><ref id="B43"><label>43.</label><mixed-citation>K. G. Strassmeier, J. B. Rice, W. Wehlau, et al., Astron. and Astrophys. 268, 671 (1993).</mixed-citation></ref><ref id="B44"><label>44.</label><mixed-citation>М. А. Лившиц, И. Ю. Алексеев, М. М. Кацова, Астрон. журн. 80, 613 (2003).</mixed-citation></ref><ref id="B45"><label>45.</label><mixed-citation>M. M. Katsova, M. A. Livshits, and G. Belvedere, Solar Phys. 216, 353 (2003).</mixed-citation></ref><ref id="B46"><label>46.</label><mixed-citation>S. V. Berdyugina and I. Tuominen, Astron. and Astrophys. 336, 25 (1998).</mixed-citation></ref><ref id="B47"><label>47.</label><mixed-citation>Е. А. Бруевич, М. М. Кацова, Д. Д. Соколов, Астрон. журн. 78, 827 (2001).</mixed-citation></ref><ref id="B48"><label>48.</label><mixed-citation>D. S. Hall, Astrophys. J. 380, L85 (1991).</mixed-citation></ref><ref id="B49"><label>49.</label><mixed-citation>K. Oláh, Z. Kolláth, and K. G. Strassmeier, Astron. and Astrophys. 356, 643 (2000).</mixed-citation></ref></ref-list></back></article>
