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<article article-type="research-article" dtd-version="1.3" 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" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cheb</journal-id><journal-title-group><journal-title xml:lang="ru">Чебышевский сборник</journal-title><trans-title-group xml:lang="en"><trans-title>Chebyshevskii Sbornik</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-8383</issn><publisher><publisher-name>Tula State Lev Tolstoy  Pedagogical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.22405/2226-8383-2026-27-2-48-59</article-id><article-id custom-type="elpub" pub-id-type="custom">cheb-2225</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Статьи</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Article</subject></subj-group></article-categories><title-group><article-title>Регуляризованная асимптотика решения сингулярно возмущенной задачи Коши для однородного уравнения Шредингера с потенциалом 𝑄 = 𝑋2, содержащей фокальные точки и сингулярные начальные условия</article-title><trans-title-group xml:lang="en"><trans-title>Regularized asymptotics of the solution of a singularly perturbed Cauchy problem for the homogeneous Schr¨odinger equation with potential 𝑄 = 𝑋2, containing focal points and singular initial conditions</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Елисеев</surname><given-names>Александр Георгиевич</given-names></name><name name-style="western" xml:lang="en"><surname>Eliseev</surname><given-names>Alexander Georgievich</given-names></name></name-alternatives><bio xml:lang="ru"><p>доктор физико-математических наук, профессор</p></bio><bio xml:lang="en"><p>doctor of physical and mathematical science, professor</p></bio><email xlink:type="simple">yeliseevag@mpei.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ратникова</surname><given-names>Татьяна Анатольевна</given-names></name><name name-style="western" xml:lang="en"><surname>Ratnikova</surname><given-names>Tatyana Anatolyevna</given-names></name></name-alternatives><bio xml:lang="ru"><p>кандидат физико-математических наук</p></bio><bio xml:lang="en"><p>candidate of physical and mathematical sciences</p></bio><email xlink:type="simple">ratnikovata@mpei.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шапошникова</surname><given-names>Дарья Алексеевна</given-names></name><name name-style="western" xml:lang="en"><surname>Shaposhnikova</surname><given-names>Daria Alekseevna</given-names></name></name-alternatives><bio xml:lang="ru"><p>кандидат физико-математических наук</p></bio><bio xml:lang="en"><p>candidate of physical and mathematical sciences</p></bio><email xlink:type="simple">shaposhnikovda@mpei.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Национальный исследовательский университет «МЭИ»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>National Research University “MPEI”</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>13</day><month>07</month><year>2026</year></pub-date><volume>27</volume><issue>2</issue><fpage>48</fpage><lpage>59</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Елисеев А.Г., Ратникова Т.А., Шапошникова Д.А., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Елисеев А.Г., Ратникова Т.А., Шапошникова Д.А.</copyright-holder><copyright-holder xml:lang="en">Eliseev A.G., Ratnikova T.A., Shaposhnikova D.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.chebsbornik.ru/jour/article/view/2225">https://www.chebsbornik.ru/jour/article/view/2225</self-uri><abstract><p>В работе строится регуляризованное асимптотическое решение сингулярно возмущенной задачи Коши для уравнения Шредингера на промежутках времени, содержащих фокальные точки. Опираясь на идеи асимптотического интегрирования задач с нестабильнымспектром указано, каким образом следует вводить регуляризирующие функции, подробно описан формализм метода регуляризации для указанного вида особенности, проведено обоснование этого алгоритма и построено асимптотической решение любого порядка по малому параметру.</p></abstract><trans-abstract xml:lang="en"><p>The article is devoted to the development of S. A. Lomov’s regularization method for singularly perturbed problems in the presence of spectral singularities in the limit operator. In particular, a regularized asymptotic solution to the singularly perturbed Cauchy problem for the Schr¨odinger equation is constructed on time intervals containing focal points. Based on the ideas of asymptotic integration of problems with an unstable spectrum, it is indicated how regularizing functions should be introduced, the formalism of the regularization method for the specified type of singularity is described in detail, the justification of this algorithm is carried out and an asymptotic solution of any order with respect to a small parameter is constructed.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>сингулярно возмущенная задача</kwd><kwd>асимптотическое решение</kwd><kwd>метод регуляризации</kwd><kwd>фокальные точки.</kwd></kwd-group><kwd-group xml:lang="en"><kwd>singularly perturbed problem</kwd><kwd>asymptotic solution</kwd><kwd>regularization method</kwd><kwd>focal points.</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Результаты А. Г. 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