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Redshifts of 10 quasar candidates in the field of the rich absorption line quasar QSO 0122-380

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 نشر من قبل Rolf Jansen
 تاريخ النشر 2000
  مجال البحث فيزياء
والبحث باللغة English




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We have obtained low resolution (~20 Angstrom FWHM) slit spectra of 10 quasar candidates located within one degree of the z = 2.181 quasar Q0122-380 with the objective of searching for signs of large scale structure matching the intervening rich absorption complexes seen over the redshift range 1.81<z<1.97 toward this object. Of the 8 confirmed quasars, 4 turn out to have redshifts z < 1.8, placing them well in front of the redshift range of interest. Two of the three confirmed quasars at redshift z > 1.8 show no obvious absorption matching that of Q0122-380 at our spectral resolution and signal-to-noise ratio. The third object at a redshift of z = 1.868 displays strong z_{abs} sim z_{em} absorption systems at z = 1.84 and z = 1.86 and a possibly BAL-like trough at z = 1.76. If not intrinsic in nature, the former two systems could potentially be related to the absorption seen in Q0122-380, albeit over a distance of 50.2 arcmin (D_perp simeq 15 h^{-1} Mpc at z = 1.9).



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