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CLASS B0445+123: a new two-image gravitational lens system

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 نشر من قبل Neal Jackson
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف M.K. Argo




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A new two-image gravitational lens system has been discovered as a result of the Cosmic Lens All-Sky Survey (CLASS). Radio observations with the VLA, MERLIN and the VLBA at increasingly higher resolutions all show two components with a flux density ratio of ~7:1 and a separation of 1.34. Both components are compact and have the same spectral index. Followup observations made with the VLA at 8.4 GHz show evidence of a feature to the south-east of the brighter component and a corresponding extension of the weaker component to the north-west. Optical observations with the WHT show ~1.7 extended emission aligned in approximately the same direction as the separation between the radio components with an R-band magnitude of 21.8 +/- 0.4.



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