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A massive star-forming region in a very early stage of evolution

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 نشر من قبل K. J. Brooks
 تاريخ النشر 2002
  مجال البحث فيزياء
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 تأليف K. J. Brooks




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We present results from a study of two luminous IRAS sources thought to be young massive star-forming regions and which have no previously detected radio continuum emission: IRAS 15596-5301 and IRAS 16272-4837. Our study incorporates sensitive ATCA radio continuum data, SEST 1.2-mm continuum (using the new SIMBA bolometer) and line data, as well as data taken from the MSX database. The results show that both sources are associated with dense molecular cores which appear to host recently formed massive stars. We argue that IRAS16272 is in a very early stage of evolution, prior to the formation of an ultra compact HII region and that IRAS15596 is in a more advanced stage and hosts a cluster of B-type stars.



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