<?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>S0185-11012017000200003</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[On the Feasibility of Photon-Limited Tip-Tilt Correction in Very Small Telescopes]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Popowicz]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Orlov]]></surname>
<given-names><![CDATA[V. G.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Silesian University of Technology Institute of Automatic Control ]]></institution>
<addr-line><![CDATA[Gliwice ]]></addr-line>
<country>Poland</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Astronomía ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<volume>53</volume>
<numero>2</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0185-11012017000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0185-11012017000200003&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0185-11012017000200003&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT The resolution of astronomical images taken from the ground is severely degraded by the atmosphere. One of the simplest methods for overcoming this problem is tip-tilt (TT) correction. This method is especially valuable for small telescopes, as it enables them to reach their diffraction limit. Unfortunately, the method requires a bright guide star to asses the blurring of astronomical images. In this study we show how various factors influence the feasibility of tip-tilt correction in very small telescopes (&#8804; 1 m). We evaluate the effect of: (1) the intensity of the guide star, (2) seeing conditions, (3) telescope size and (4) sky background. The results are obtained from data simulated using the Random Wave Vector method. The dependencies presented in this paper can be used to predict the sky coverage of small telescopes with TT correction for a wide range of observational conditions.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN La resolución de las imágenes astronómicas obtenidas desde la superficie terrestre se ve fuertemente degradada por la atmósfera. Uno de los métodos más sencillos para superar este problema es la corrección ladeo-inclinación (TT por sus siglas en inglés: Tip-Tilt). Este método es valioso especialmente para telescopios pequeños, pues permite que alcancen su límite de difracción. Sin embargo, el método requiere de una estrella guía brillante para evaluar la degradación de las imágenes. Estudiamos la manera en que varios factores afectan la viabilidad de la corrección TT para telescopios pequeños (&#8804; 1 m). Evaluamos los efectos de: (1) la magnitud de la estrella guía; (2) la turbulencia atmosférica (el &#8220;seeing&#8221;); (3) el tamaño del telescopio; y (4) el fondo celeste. Los resultados se obtienen con datos simulados usando el m´etodo del vector de onda al azar. Las dependencias que encontramos pueden ser usadas para predecir la cobertura celeste de telescopios pequeños con corrección TT para una gran variedad de condiciones observacionales.]]></p></abstract>
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<kwd lng="en"><![CDATA[atmospheric effects]]></kwd>
<kwd lng="en"><![CDATA[instrumentation]]></kwd>
<kwd lng="en"><![CDATA[high angular resolution]]></kwd>
<kwd lng="en"><![CDATA[techniques: image processing]]></kwd>
</kwd-group>
</article-meta>
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