<?xml version="1.0" encoding="ISO-8859-1"?><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">
<front>
<journal-meta>
<journal-id>0016-7169</journal-id>
<journal-title><![CDATA[Geofísica internacional]]></journal-title>
<abbrev-journal-title><![CDATA[Geofís. Intl]]></abbrev-journal-title>
<issn>0016-7169</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Geofísica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0016-71692022000200144</article-id>
<article-id pub-id-type="doi">10.22201/igeof.00167169p.2022.61.2.2201</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Voyager&#8217;s Observations in the Vicinity of the Heliopause]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Caballero-López]]></surname>
<given-names><![CDATA[R. A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Richardson]]></surname>
<given-names><![CDATA[J. D.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Geofísica ]]></institution>
<addr-line><![CDATA[ CDMX]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Massachusetts Institute of Technology Kavli Institute for Astrophysics and Space Research ]]></institution>
<addr-line><![CDATA[Cambridge MA]]></addr-line>
<country>USA</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2022</year>
</pub-date>
<volume>61</volume>
<numero>2</numero>
<fpage>144</fpage>
<lpage>152</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0016-71692022000200144&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0016-71692022000200144&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0016-71692022000200144&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT This work analyzes Voyager 2 observations on November 2018 and compares them with Voyager 1 data at the vicinity of the heliopause in July-August 2012. We describe the plasma and cosmic-ray variations at the radial distance of &#8776; 1 astronomical unit (AU) from the heliopause. We use a simple convection-diffusion cosmic-ray modulation model to qualitatively explain the particle observations. We found a thin layer, with a thickness of &#8776; 0.04 AU where the radial component of the solar wind speed vanished, the galactic cosmic ray intensity rapidly increased to reach its heliosphere boundary level, and low-energy heliospheric ion intensity drooped. We called this layer the &#8220;skin of the heliosphere&#8221;. Plasma data suggest that Voyager 2 crossed the heliopause on November 5, 2018, at the radial distance of 119.03 AU. We apply our analysis to Voyager 1 observations and conclude that similar behavior in solar wind speed could qualitatively explain the GCR counting rate and that the &#8220;skin of the heliosphere&#8221; maybe a global characteristic along the heliopause.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Este trabajo analiza las observaciones del Voyager 2 en noviembre de 2018 y las compara con lo detectado por el Voyager 1 en las proximidades de la heliopausa en julio-agosto de 2012. Describimos las variaciones del plasma y los rayos cósmicos a la distancia radial de &#8776; 1 unidad astronómica (AU) de la heliopausa. Usamos un modelo simple de modulación de los rayos cósmicos por convección-difusión para explicar cualitativamente las observaciones de partículas. Encontramos una capa delgada, con un espesor de 0.04 AU en la cual desaparece la componente radial de la velocidad del viento solar, la intensidad de los rayos cósmicos galácticos aumenta rápidamente para alcanzar su nivel en la frontera de la heliosfera, y disminuye la intensidad de los iones heliosféricos de baja energía. Llamamos a esta capa la &#8220;piel de la heliosfera&#8221;. Los datos de plasma sugieren que el Voyager 2 cruzó la heliopausa el 5 de noviembre de 2018, a la distancia radial de 119.03 AU. Aplicamos nuestro análisis a las observaciones del Voyager 1 y concluimos que un comportamiento similar en la velocidad del viento solar podría cualitativamente explicar la intensidad observada de los rayos cósmicos galácticos y que la &#8220;piel de la heliosfera&#8221; puede ser una característica global a lo largo de la heliopausa.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Sol]]></kwd>
<kwd lng="es"><![CDATA[heliosfera]]></kwd>
<kwd lng="es"><![CDATA[heliopausa]]></kwd>
<kwd lng="es"><![CDATA[viento solar y rayos cósmicos]]></kwd>
<kwd lng="en"><![CDATA[Sun]]></kwd>
<kwd lng="en"><![CDATA[heliosphere]]></kwd>
<kwd lng="en"><![CDATA[heliopause]]></kwd>
<kwd lng="en"><![CDATA[solar wind and cosmic rays]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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