4.2 Previously identified inverted-spectrum sources
B1145-071: is a binary quasar with radio faint and radio bright
components (Djorgovski et al. 1987) Its redshift is 1.342. The spectrum
in Fig. 4 is rather flat with slightly convex upper envelope.
The core region extends westward toward the extended emission seen in
the VLBApls, USNO, and VLBA2cm1 images.
1145-071: Djorgovski et al. (1987) and Kochanek, Falco, &
Munoz (1999) reported the source as a probable binary quasar,
with two optical features at the same redshift and separated
by 4.2" in projection. Our image shows a secondary component
at the same distance (2.1 mas) and position (P.A. = -63^deg^)
as in the RRFID image.
B1145-071 (z = 1.342). - This source was among the first discovered real
binary quasars and the very first binary in which one quasar is radio
bright and the other is radio faint (Djorgovski et al. 1987). Our radio
spectrum is inverted up to 5 GHz. The source exhibits variability at least
in the centimeter region. The 5 GHz data were obtained during two epochs
only, whereas the 8 GHz data set spans over 18 yr of time, and thus the
flux minima at 5 GHz may not represent the true quiescent state. The source
probably is a variable source with a flat spectrum that becomes inverted