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 <front>
  <journal-meta>
   <journal-id journal-id-type="publisher-id">Solnechno-Zemnaya Fizika</journal-id>
   <journal-title-group>
    <journal-title xml:lang="en">Solnechno-Zemnaya Fizika</journal-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Солнечно-земная физика</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">13890</article-id>
   <article-id pub-id-type="doi">10.12737/22597</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">Sporadic potassium layers and their connection to sporadic E layers in the mesopause region at Beijing, China</article-title>
    <trans-title-group xml:lang="ru">
     <trans-title>Спорадические калиевые слои и их связь со спорадическими Е-слоями в области мезопаузы над Пекином (Китай)</trans-title>
    </trans-title-group>
   </title-group>
   <contrib-group content-type="authors">
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Цзин</surname>
       <given-names>Цзяо </given-names>
      </name>
      <name xml:lang="en">
       <surname>Jing</surname>
       <given-names>Jiao </given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-1"/>
     <xref ref-type="aff" rid="aff-2"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Готао</surname>
       <given-names>Ян </given-names>
      </name>
      <name xml:lang="en">
       <surname>Guotao</surname>
       <given-names>Yang </given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-3"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Цзихун</surname>
       <given-names>Ван </given-names>
      </name>
      <name xml:lang="en">
       <surname>Jihong</surname>
       <given-names>Wang </given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-4"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Сюэу</surname>
       <given-names>Чэн </given-names>
      </name>
      <name xml:lang="en">
       <surname>Xuewu</surname>
       <given-names>Cheng </given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-5"/>
    </contrib>
    <contrib contrib-type="author">
     <name-alternatives>
      <name xml:lang="ru">
       <surname>Фацюнь</surname>
       <given-names>Ли </given-names>
      </name>
      <name xml:lang="en">
       <surname>Faqun</surname>
       <given-names>Li </given-names>
      </name>
     </name-alternatives>
     <xref ref-type="aff" rid="aff-6"/>
    </contrib>
   </contrib-group>
   <aff-alternatives id="aff-1">
    <aff>
     <institution xml:lang="ru">Главная государственная лаборатория исследования  космической погоды, Национальный центр космических  исследований, Китайская академия наук</institution>
     <city>Пекин</city>
     <country>Китайская Республика</country>
    </aff>
    <aff>
     <institution xml:lang="en">State Key Laboratory of Space Weather, National Space  Science Center, Chinese Academy of Sciences</institution>
     <city>Beijing</city>
     <country>Taiwan</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-2">
    <aff>
     <institution xml:lang="ru">Объединенная Китайско-Бразильская лаборатория  исследования космической погоды,  Китайская академия наук</institution>
     <city>Сан-Жозе-дус-Кампус</city>
     <country>Бразилия</country>
    </aff>
    <aff>
     <institution xml:lang="en">China-Brazil Joint Laboratory for Space Weather,  Chinese Academy of Sciences</institution>
     <city>8 São Jose dos Campos</city>
     <country>Brazil</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-3">
    <aff>
     <institution xml:lang="ru">Главная государственная лаборатория исследования  космической погоды, Национальный центр космических  исследований, Китайская академия наук</institution>
     <city>Пекин</city>
     <country>Китайская Республика</country>
    </aff>
    <aff>
     <institution xml:lang="en">State Key Laboratory of Space Weather, National Space  Science Center, Chinese Academy of Sciences</institution>
     <city>Beijing</city>
     <country>Taiwan</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-4">
    <aff>
     <institution xml:lang="ru">Национальный центр науки о космосе, Академия наук КНР</institution>
     <city>Пекин</city>
     <country>Китайская Республика</country>
    </aff>
    <aff>
     <institution xml:lang="en">National Astronomical Observatories of Chinese Academy of Sciences</institution>
     <city>Beijing</city>
     <country>Taiwan</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-5">
    <aff>
     <institution xml:lang="ru">Уханьский Институт физики и математики,  Китайская академия наук</institution>
     <city>Ухань</city>
     <country>Китайская Республика</country>
    </aff>
    <aff>
     <institution xml:lang="en">Wuhan Institute of Physics and Mathematics,  Chinese Academy of Sciences</institution>
     <city>Wuhan</city>
     <country>Taiwan</country>
    </aff>
   </aff-alternatives>
   <aff-alternatives id="aff-6">
    <aff>
     <institution xml:lang="ru">Уханьский Институт физики и математики,  Китайская академия наук</institution>
     <city>Ухань</city>
     <country>Китайская Республика</country>
    </aff>
    <aff>
     <institution xml:lang="en">Wuhan Institute of Physics and Mathematics,  Chinese Academy of Sciences</institution>
     <city>Wuhan</city>
     <country>Taiwan</country>
    </aff>
   </aff-alternatives>
   <pub-date publication-format="print" date-type="pub" iso-8601-date="2016-11-15T00:00:00+03:00">
    <day>15</day>
    <month>11</month>
    <year>2016</year>
   </pub-date>
   <pub-date publication-format="electronic" date-type="pub" iso-8601-date="2016-11-15T00:00:00+03:00">
    <day>15</day>
    <month>11</month>
    <year>2016</year>
   </pub-date>
   <volume>3</volume>
   <issue>2</issue>
   <fpage>64</fpage>
   <lpage>69</lpage>
   <self-uri xlink:href="https://naukaru.ru/en/nauka/article/13890/view">https://naukaru.ru/en/nauka/article/13890/view</self-uri>
   <abstract xml:lang="ru">
    <p>Разработка двухлучевого лазерного лидара для измерения калиевого (K) слоя над Пекином (40.5° N, 116.2° E) была успешно осуществлена в 2010 г. Приведены параметры спорадических Ks-слоев и их распределения. Получено сезонное распределение частоты появления слоя Ks с двумя максимумами в июле и январе. Сезонное распределение частоты появления слоя Es над Пекином отличается от Ks. Тем не менее, хорошая корреляция Es и Ks в отдельных исследованиях подтверждает механизм нейтрализации ионов металла в опускающемся Е-слое.</p>
   </abstract>
   <trans-abstract xml:lang="en">
    <p>A double-laser beam lidar to measure potassium (K) layer at Beijing (40.5° N, 116.2° E) was successfully developed in 2010. The parameters of sporadic Ks layers and their distributions were given. The seasonal distribution of Ks occurrence frequency was obtained, with two maxima in July and January. The seasonal distributions of sporadic Es layer occurrence frequency over Beijing differ from those of Ks. However, the good correlation between Es and Ks in the case-by-case studies supports the mechanism of neutralization of metal ions in a descending Es layer.</p>
   </trans-abstract>
   <kwd-group xml:lang="ru">
    <kwd>лидар</kwd>
    <kwd>спорадические калиевые слои</kwd>
    <kwd>спорадические Е-слои</kwd>
   </kwd-group>
   <kwd-group xml:lang="en">
    <kwd>lidar</kwd>
    <kwd>sporadic potassium layers</kwd>
    <kwd>sporadic E layers</kwd>
   </kwd-group>
  </article-meta>
 </front>
 <body>
  <p>1. INTRODUCTIONMeteoric metal (Na, K, Ca, Mg, etc.) layers between 80 and 110 km originate from meteor ablation [Plane, 1991; Kane et al., 2001]. Lidar observations and studies of metal layers have been carried out for about 40 years, promoting better understanding of chemical and dynamic processes in the mesopause region. Sporadic or narrow metal layers (Ns) were often observed in lidar data.There are fewer lidar observations of the K layer than the sodium (Na) one. This is because the density of the K layer is approximately two orders of magnitude lower than that of the Na layer [Megie et al., 1978]. While several lidar observations of K layers over dif-ferent regions were made [Eska, Hoffner, 1988; Eska et al., 1998; von Zahn et al., 1999; Friedman et al., 2002], reports on Ks layers were limited in number: two dif-ferent sporadic layer events were analyzed by Delgado et al. [2012], and the Ks layers were observed in both neutral K and Ca+ layers with a lidar. A temperature-dependent chemical model was also developed to simulate the observations: one event that occurred be-tween June 12 and 13, 2002 was successfully reproduced. Raizada et al. [2004] found that sudden increases in both K and Ca densities were often observed during early morning hours or at night when meteor showers occurred.Among many mechanisms for interpreting the Ns formation, the most promising is the neutralization of ions, as evidenced by the high temporal and spatial correlation between enhanced metal atoms and Es layers [Gardner et al., 1993; Friedman et al., 2000; Williams et al., 2007; Delgado et al., 2012; Dou et al., 2012]. However, no reports examined the relationship between the Ks and Es layers.In this paper, using lidar and digital ionosonde observations from the newly launched Meridian Project, the aim of which is to help researchers better understand and predict space weather conditions over China, we statistically analyzed the Ks and Es layer events at Beijing. The observational data were obtained by the Na-K lidar at Beijing from November 2010 to October 2011 and from May 2013 to April 2014.</p>
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