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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Solar-Terrestrial Physics</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Solar-Terrestrial Physics</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Солнечно-земная физика / Solnechno-Zemnaya Fizika / Solar-Terrestrial Physics</trans-title>
    </trans-title-group>
   </journal-title-group>
   <issn publication-format="online">2712-9640</issn>
  </journal-meta>
  <article-meta>
   <article-id pub-id-type="publisher-id">57147</article-id>
   <article-id pub-id-type="doi">10.12737/szf-93202305</article-id>
   <article-categories>
    <subj-group subj-group-type="toc-heading" xml:lang="ru">
     <subject>Результаты  исследований</subject>
    </subj-group>
    <subj-group subj-group-type="toc-heading" xml:lang="en">
     <subject>Results of current research</subject>
    </subj-group>
    <subj-group>
     <subject>Результаты  исследований</subject>
    </subj-group>
   </article-categories>
   <title-group>
    <article-title xml:lang="en">Influence of strong solar proton events on propagation of radio signals in the VLF range in a high-latitude region</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Влияние сильных солнечных протонных событий на распространение радиосигналов в диапазоне ОНЧ в области высоких широт</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6824-312X</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Ахметов</surname>
       <given-names>Олег Иршатович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Ahmetov</surname>
       <given-names>Oleg Irshatovich</given-names>
      </name>
     </name-alternatives>
     <email>Akhmetov.O.I@yandex.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-1"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Мингалев</surname>
       <given-names>Игорь Викторович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Mingalev</surname>
       <given-names>Igor Viktorovich</given-names>
      </name>
     </name-alternatives>
     <email>mingalev_i@pgia.ru</email>
     <bio xml:lang="ru">
      <p>доктор физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>doctor of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-2"/>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Мингалев</surname>
       <given-names>Олег Викторович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Mingalev</surname>
       <given-names>Oleg Viktorovich</given-names>
      </name>
     </name-alternatives>
     <email>mingalev_o@pgia.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-4"/>
     <xref ref-type="aff" rid="aff-5"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Белаховский</surname>
       <given-names>Владимир Борисович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Belahovskiy</surname>
       <given-names>Vladimir Borisovich</given-names>
      </name>
     </name-alternatives>
     <email>belakhov@mail.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-6"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Маурчев</surname>
       <given-names>Евгений Александрович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Maurchev</surname>
       <given-names>Evgeniy Aleksandrovich</given-names>
      </name>
     </name-alternatives>
     <email>maurchev@pgia.ru</email>
     <xref ref-type="aff" rid="aff-7"/>
    </contrib>
    <contrib contrib-type="author">
     <contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5001-9768</contrib-id>
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Ларченко</surname>
       <given-names>Алексей Викторович</given-names>
      </name>
      <name xml:lang="en">
       <surname>Larchenko</surname>
       <given-names>Aleksey Viktorovich</given-names>
      </name>
     </name-alternatives>
     <email>alexey.larchenko@gmail.com</email>
     <xref ref-type="aff" rid="aff-8"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Суворова</surname>
       <given-names>Зоя Викторовна</given-names>
      </name>
      <name xml:lang="en">
       <surname>Suvorova</surname>
       <given-names>Zoya Viktorovna</given-names>
      </name>
     </name-alternatives>
     <email>suvorova@pgia.ru</email>
     <xref ref-type="aff" rid="aff-9"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Балабин</surname>
       <given-names>Юрий Васильевич</given-names>
      </name>
      <name xml:lang="en">
       <surname>Balabin</surname>
       <given-names>Yuriy Vasilyevich</given-names>
      </name>
     </name-alternatives>
     <email>balabin@pgia.ru</email>
     <bio xml:lang="ru">
      <p>кандидат физико-математических наук;</p>
     </bio>
     <bio xml:lang="en">
      <p>candidate of physical and mathematical sciences;</p>
     </bio>
     <xref ref-type="aff" rid="aff-10"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">ФГБУН &quot;Полярный геофизический институт&quot;</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">ФГБУН &quot;Полярный геофизический институт&quot;</institution>
     <city>Апатиты</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт РАН</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute RAS</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">Мурманский арктический государственный университет</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Murmansk Arctic State University</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-4">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт РАН</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute RAS</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-5">
    <aff>
     <institution xml:lang="ru">Мурманский арктический государственный университет</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Murmansk Arctic State University</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-6">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-7">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт КНЦ РАН</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute KSC RAS</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-8">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-9">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт РАН</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute RAS</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-10">
    <aff>
     <institution xml:lang="ru">Полярный геофизический институт КНЦ РАН</institution>
     <city>Апатиты</city>
     <country>Россия</country>
    </aff>
    <aff>
     <institution xml:lang="en">Polar Geophysical Institute KSC RAS</institution>
     <city>Apatity</city>
     <country>Russian Federation</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2023-09-29T17:23:49+03:00">
    <day>29</day>
    <month>09</month>
    <year>2023</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2023-09-29T17:23:49+03:00">
    <day>29</day>
    <month>09</month>
    <year>2023</year>
   </pub-date>
   <volume>9</volume>
   <issue>3</issue>
   <fpage>33</fpage>
   <lpage>46</lpage>
   <history>
    <date date-type="received" iso-8601-date="2023-02-11T00:00:00+03:00">
     <day>11</day>
     <month>02</month>
     <year>2023</year>
    </date>
    <date date-type="accepted" iso-8601-date="2023-06-27T00:00:00+03:00">
     <day>27</day>
     <month>06</month>
     <year>2023</year>
    </date>
   </history>
   <self-uri xlink:href="https://zh-szf.ru/en/nauka/article/57147/view">https://zh-szf.ru/en/nauka/article/57147/view</self-uri>
   <abstract xml:lang="ru">
    <p>Методами вычислительного эксперимента исследованы особенности распространения сигналов радиотехнической системы дальней навигации РСДН-20 в высокоширотном участке волновода Земля–ионосфера во время солнечных протонных событий. В работе рассмотрены два протонных события GLE (Ground Level Enhancement) — 13 декабря 2006 г. (GLE70) и 10 сентября 2017 г. (GLE72). Профили концентрации электронов строились по моделям GDMI (Global Dynamic Model of Ionosphere)   и RUSCOSMICS, разработанной в Полярном геофизическом институте. Приведены оценки изменений фазы и амплитуды сигналов РСДН-20 во время высыпаний высокоэнергичных протонов в высокоширотной области волновода Земля–ионосфера. По результатам вычислительных экспериментов и анализа затухания электромагнитного сигнала на основе аналитических решений уравнений Максвелла в замагниченной ионосферной плазме обнаружена закономерность в частотной зависимости затухания сигнала, связанная одновременно с высотой отражения сигнала, профилями электронной концентрации и частотой столкновений электронов с нейтральными частицами и с ионами. Обсуждаются ограничения метода вычислительного эксперимента, приведено сравнение результатов моделирования с данными обсерваторий ПГИ «Ловозеро» и «Тулома».</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>In this paper, we examine the features of RSDN-20 signal propagation in a high-latitude Earth–ionosphere waveguide during solar proton events, using computational experiment methods. We have analyzed two proton ground-level enhancement (GLE) events of December 13, 2006 (GLE70) and September 10, 2017 (GLE72). Electron density profiles were constructed using the Global Dynamic Model of Ionosphere (GDMI) and the RUSCOSMICS model, developed at PGI. We present estimated phase and amplitude changes in RSDN-20 signals during precipitation of high-energy protons in the high-latitude region of the Earth–ionosphere waveguide. From the results of computational experiments and the analysis of the electromagnetic signal attenuation based on analytical Maxwell’s equation system solution in magnetized ionospheric plasma, we have found a pattern in the signal attenuation frequency dependence associated simultaneously with the signal reflection height, electron density profiles, and the collision frequency of electrons with neutral particles and ions. We discuss limitations of the computational experiment method and compare simulation results with data from Lovozero and Tuloma observatories.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>численное моделирование</kwd>
    <kwd>распространение радиоволн</kwd>
    <kwd>ионосфера</kwd>
    <kwd>высокие широты</kwd>
    <kwd>GLE</kwd>
    <kwd>ОНЧ</kwd>
    <kwd>РСДН-20</kwd>
    <kwd>GDMI</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>numerical modeling</kwd>
    <kwd>radio wave propagation</kwd>
    <kwd>ionosphere</kwd>
    <kwd>high latitudes</kwd>
    <kwd>GLE</kwd>
    <kwd>VLF</kwd>
    <kwd>RSDN-20</kwd>
    <kwd>GDMI</kwd>
   </kwd-group>
   <funding-group>
    <funding-statement xml:lang="ru">Исследование выполнено за счет гранта Российского научного фонда (проект № 18-77-10018) (Ахметов О.И., Белаховский В.Б., Маурчев Е.А., Балабин Ю.В.) [https://rscf.ru/project/18-77-10018/]</funding-statement>
    <funding-statement xml:lang="en">The work was financially supported by RSF Grant (Project No. 18-77-10018) (Akhmetov O.I., Belakhovsky V.B., Maurchev E.A., Balabin Yu.V.) [https://rscf.ru/project/18-77-10018 /]</funding-statement>
   </funding-group>
  </article-meta>
 </front>
 <body>
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