<?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>0185-1101</journal-id>
<journal-title><![CDATA[Revista mexicana de astronomía y astrofísica]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. astron. astrofis]]></abbrev-journal-title>
<issn>0185-1101</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Astronomía]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0185-11012016000200329</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[NGC 2440: a morpho-kinematical model]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lago]]></surname>
<given-names><![CDATA[P.J.A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Costa]]></surname>
<given-names><![CDATA[R.D.D.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,USP IAG ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Brazil</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2016</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2016</year>
</pub-date>
<volume>52</volume>
<numero>2</numero>
<fpage>329</fpage>
<lpage>337</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0185-11012016000200329&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0185-11012016000200329&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0185-11012016000200329&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: The 3D structure and position-velocity (P-V) diagrams of NGC 2440 were modeled aiming to describe the morphology of this object, specially its core. High resolution spectra, HST images and P-V diagrams were used to reproduce the 3D structure of the nebula using SHAPE. The best model for the nebula is a torus torn apart in three pieces by interaction with the surrounding medium, either winds or the radiation field. Orientation angles of 27 ± 5 and &#8722;5 ± 3 degrees were derived for the bipolar components at PA of 85 and 35 degrees respectively. No additional bipolar lobes were required to model the observed features. Using our velocity field, a distance of 1.8 ± 0.5 kpc was derived for the nebula. These results are the first obtained for NGC 2440 from modeling in a 3D environment.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Modelamos la estructura en 3D y los diagramas posición-velocidad de NGC 2440, con el objeto de describir la morfología de este objeto, especialmente la de su región central. Empleamos espectros de alta resolución, imágenes del HST y diagramas P-V para reproducir la estructura en 3D de la nebulosa, usando SHAPE. El mejor modelo es un toro rasgado en tres sitios por la interacción con el medio circundante, ya sea vientos o campos radiativos. Se obtuvieron ángulos de orientación de 27 ± 5 y &#8722;5 ± 3 grados para las componentes bipolares situadas en ángulos de posición de 85 y 35 grados, respectivamente. No fueron necesarias otras componentes bipolares para modelar las características observadas. Con el campo de velocidades que derivamos se obtiene una distancia de 1.8 ± 0.5 kpc para esta nebulosa. Estos son los primeros resultados obtenidos para NGC 2440 mediante modelos en un entorno 3D.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[ISM: kinematics and dynamics]]></kwd>
<kwd lng="en"><![CDATA[methods: numerical]]></kwd>
<kwd lng="en"><![CDATA[planetary nebulae: individual (NGC 2440)]]></kwd>
<kwd lng="en"><![CDATA[techniques: spectroscopic.]]></kwd>
</kwd-group>
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