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Is Messier 74 a barred spiral galaxy?

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 نشر من قبل Marc Seigar
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Marc S. Seigar




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We have obtained ground-based I, J and K band images of the spiral galaxy, Messier 74 (NGC 628). This galaxy has been shown to possess a circumnuclear ring of star formation from both near-infrared spectroscopy of CO absorption and sub-millimetre imaging of CO emission. Circumnuclear rings of star formation are believed to exist only as a result of a bar potential. In this paper we show evidence for a weak oval distortion in the centre of M74. We use the results of Combes & Gerin (1985) to suggest that this weak oval potential is responsible for the circumnuclear ring of star formation observed in M74.



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