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Observations
First discovered as a strong and variable X-ray source (Cooke et al. 1978), MR 2251-178 was subsequently identified as a quasar at a redshift of
(Canizares et al. 1978). Optical imagery and spectroscopy
have detected two ionized gas components around the quasar: an
elongated, highly-ionized circum-nuclear component of diameter
kpc, and an extended envelope of faint H- and
[OIII]-emitting filaments out to a radius of kpc (e.g.,
Bergeron et al. 1983; Macchetto et al. 1990). Spectroscopic
observations have determined that the extended ionized gas component,
while undoubtedly associated with the quasar, is not following its
rotation pattern (Nørgaard-Nielsen et al. 1986; Mulder & Valentijn
1992).
Figure 1 presents our H imagery of MR 2251-178. In the
discussion that follows, we assume km s Mpc
and a corresponding image scale of 1.9 kpc arcsec.
Figure 1:
Deep imagery of the field surrounding the quasar MR 2251-178. Panels
and are 1200 second exposures of H at redshifts of 0.0640
and 0.0645, respectively. Panel is an I-band continuum image of
the same field, illustrating a number of galaxies in the
cluster. Panel is a summed H image. All panels are 3 in
size, with north up and east to the left.
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Subsections
Next: Morphology
Up: A Very Extended Ionized
Previous: Introduction
Patrick Shopbell
2000-11-28