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Accurate Redshifts and Classifications for 110 Radio-Loud AGNs

Michael Eracleous·Jules P. Halpern
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Abstract

We report accurate redshifts of 110 active galaxies (mostly radio-loud objects at z<0.4) observed in the course of a survey to find broad, double-peaked emission lines. These redshifts are measured from the narrow emission lines of these objects and are accurate to at least one part in 10^4 . For each object we determine a redshift from high- and low-ionization lines separately, as well as an average redshift from all the available lines. We find that in about 15% of cases, the low-ionization lines yield a slightly higher redshift than the high-ionization lines; the average redshift difference amounts to a velocity difference of approximately 80 km/s. In addition to the redshift measurements we also report revised redshifts for two objects as well as new classifications for three narrow-line objects.

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Michael Eracleous, Jules P. Halpern. 2003-09-17. Accurate Redshifts and Classifications for 110 Radio-Loud AGNs. https://doi.org/10.1086/379823

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