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<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">647559</article-id><article-id pub-id-type="doi">10.31857/S0004629923080017</article-id><article-id pub-id-type="edn">HIQYGP</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">NEUTRON STARS IN A UNIFORM DENSITY APPROXIMATION</article-title><trans-title-group xml:lang="ru"><trans-title>Нейтронные звезды в приближении однородного шара</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Bisnovatyi-Kogan</surname><given-names>G. S.</given-names></name><name xml:lang="ru"><surname>Бисноватый-Коган</surname><given-names>Г. С.</given-names></name></name-alternatives><email>gkogan@mx.iki.rssi.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/><xref ref-type="aff" rid="aff3"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Patraman</surname><given-names>E. A.</given-names></name><name xml:lang="ru"><surname>Патраман</surname><given-names>Е. А.</given-names></name></name-alternatives><email>gkogan@mx.iki.rssi.ru</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff3"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Space Research Institute of the Russian Academy of Sciences</institution></aff><aff><institution xml:lang="ru">Институт космических исследований РАН</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">National Research Nuclear University MEPhI</institution></aff><aff><institution xml:lang="ru">Национальный исследовательский ядерный университет МИФИ</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">Moscow Institute of Physics and Technology</institution></aff><aff><institution xml:lang="ru">Московский физико-технический институт МФТИ</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2023-08-01" publication-format="electronic"><day>01</day><month>08</month><year>2023</year></pub-date><volume>100</volume><issue>8</issue><fpage>721</fpage><lpage>734</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, Г.С. Бисноватый-Коган, Е.А. Патраман</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2023, Г.С. Бисноватый-Коган, Е.А. Патраман</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="en">Г.С. Бисноватый-Коган, Е.А. Патраман</copyright-holder><copyright-holder xml:lang="ru">Г.С. Бисноватый-Коган, Е.А. Патраман</copyright-holder></permissions><self-uri xlink:href="https://journals.eco-vector.com/0004-6299/article/view/647559">https://journals.eco-vector.com/0004-6299/article/view/647559</self-uri><abstract xml:lang="en"><p id="idm45181324623968">Models of neutron stars are considered in the case of a uniform density distribution. A universal algebraic equation is obtained that is valid for any equation of state. This equation allows us to find the approximate mass of a star of a given density without resorting to the integration of differential equations. Solutions for various equations of state, including more realistic ones, are presented in the paper and differ from the exact solutions obtained by numerical integration of differential equations by no more than 20%.</p></abstract><trans-abstract xml:lang="ru"><p id="idm45181324622240">Рассмотрены модели нейтронных звезд в случае однородного распределения плотности. Получено алгебраическое уравнение равновесия, справедливое для любого уравнения состояния. Данное уравнение позволяет приближенно оценить массу звезды заданной плотности, не прибегая к интегрированию дифференциальных уравнений. Модели однородных нейтронных звезд для разных уравнений состояния, представленные в работе, отличаются в области максимума массы от точных решений, получаемых при численном интегрировании дифференциальных уравнений, не более, чем на \( \sim \)20%.</p></trans-abstract><kwd-group xml:lang="en"><kwd>neutron stars</kwd><kwd>uniform model</kwd><kwd>general theory of relativity</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>нейтронные звезды</kwd><kwd>однородная модель</kwd><kwd>Общая теория относительности (ОТО)</kwd></kwd-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>E. C. Stoner, London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Ser. 7 9 (60), 944 (1930).</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>R. H. Fowler, Monthly Not. Roy. Astron. Soc. 87, 114 (1926).</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>J. 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