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Ultraviolet structure in the lensed QSOs 0957+561

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 نشر من قبل J. B. Hutchings
 تاريخ النشر 2003
  مجال البحث فيزياء
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 تأليف J. B. Hutchings




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Imaging and spectra of the lensed QSO pair 0957+561 are presented and discussed. The data are principally those from the STIS NUV MAMA, and cover rest wavelengths from 850A to 1350A. The QSOs are both extended over about 1 arcsec, with morphology that matches with a small rotation, and includes one feature aligned with the VLBI radio jets. This is the first evidence of lensed structure in the host galaxy. The off-nuclear spectra arise from emission line gas and a young stellar population. The gas has velocity components with radial velocities at least 1000 km/s with respect to the QSO BLR, and may be related to the damped Ly alpha absorber in the nuclear spectra.

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