<?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>2222-145X</journal-id>
<journal-title><![CDATA[Reportes científicos de la FACEN]]></journal-title>
<abbrev-journal-title><![CDATA[Rep. cient. FACEN]]></abbrev-journal-title>
<issn>2222-145X</issn>
<publisher>
<publisher-name><![CDATA[Facultad de Ciencias Exactas y Naturales]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2222-145X2018000200088</article-id>
<article-id pub-id-type="doi">10.18004/rcfacen.2018.9.2.88</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Estudio multifrecuencia de la galaxia IZw18]]></article-title>
<article-title xml:lang="en"><![CDATA[Multifrecuency study of galaxy IZw18]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gómez]]></surname>
<given-names><![CDATA[José María]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Kehrig]]></surname>
<given-names><![CDATA[Carolina]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional de Asunción Facultad de Ciencias Exactas y Naturales Departamento de Física]]></institution>
<addr-line><![CDATA[San Lorenzo ]]></addr-line>
<country>Paraguay</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Instituto de Astrofísica de Andalucía  ]]></institution>
<addr-line><![CDATA[Andalucía ]]></addr-line>
<country>España</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Consejo Superior de Investigaciones Científicas  ]]></institution>
<addr-line><![CDATA[Madrid ]]></addr-line>
<country>España</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<volume>9</volume>
<numero>2</numero>
<fpage>88</fpage>
<lpage>98</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.iics.una.py/scielo.php?script=sci_arttext&amp;pid=S2222-145X2018000200088&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.iics.una.py/scielo.php?script=sci_abstract&amp;pid=S2222-145X2018000200088&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.iics.una.py/scielo.php?script=sci_pdf&amp;pid=S2222-145X2018000200088&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: En este trabajo se ha realizado un estudio multifrecuencia de la galaxia enana compacta azul IZw18. Se la considera una galaxia con características similares a las galaxias primitivas del universo lejano, dada su baja metalicidad y su importante eficiencia de formación estelar. Se utilizaron imágenes del WISE (infrarrojo cercano/medio) [California Institute of Technology, 2015] 2MASS (infrarrojo cercano) ;Skrutskie et al., 2006, SDSS (visible) ;Gal &amp; Evans, 2004; y GALEX (ultravioleta) V; Neff &amp; Myers, 2012; de forma a cubrir un amplio rango de longitudes de onda. De cada imagen se obtuvo la densidad de flujo de forma a ajustarlas a las salidas del código de modelado de galaxias GRASIL. El modelo de mejor ajuste muestra una Densidad Espectral de Energía con altos valores de densidad de flujo para longitudes de onda menores. La historia de la tasa de formación estelar obtenida muestra una formación estelar temprana desde hace unos 14 Gyr a una tasa del orden de los 1x10-4 MSol/yr, que creciendo lentamente alcanza una tasa de 0.094 MSol/yr.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: This paper has done a multifrequency study of the blue compact dwarf galaxy IZw18. It is considered a galaxy similar to primitive galaxies in the distant universe features, given their low metallicity and high rate of star formation. WISE images (near infrared / medium), 2MASS (near infrared), SDSS (visible) and GALEX (ultraviolet) so as to cover a wide range of wavelengths were used. Each image flux density so as to adjust to the outputs of code modeling GRASIL galaxies was obtained the best fit model shows a Spectral Energy Distribution with high flux density values for shorter wavelengths. The history of star formation rate obtained shows an early star formation since about 14 Gyr at a rate of the order of 1x10-4 Msol /yr, which grow slowly reaching a rate of 0.094 Msol / yr.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Multifrecuencia]]></kwd>
<kwd lng="es"><![CDATA[densidad de flujo]]></kwd>
<kwd lng="es"><![CDATA[densidad espectral de energía]]></kwd>
<kwd lng="en"><![CDATA[Multfrecuency]]></kwd>
<kwd lng="en"><![CDATA[flux density]]></kwd>
<kwd lng="en"><![CDATA[spectral energy distribution.]]></kwd>
</kwd-group>
</article-meta>
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