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Date and Time of the Query: 2019-08-25 T13:54:09 PDT
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Notes for object [HB89] 0607-157

6 note(s) found in NED.


1. 2006AJ....131.1262H
Re:[HB89] 0607-157
0607-157: We find a limit of |m_c_| < 0.21% in the core at 15 GHz in 2003
March. Homan & Wardle (2003) measured only m_c_ = -0.23% +- 0.12% in the
core at 15 GHz in 1998 January, but they simultaneously detected m_c_ =
-0.65% +- 0.07% in the core at 8 GHz. Homan et al. (2001) detected
circular polarization in the core of m_c_ = -0.18% +- 0.05% at 5 GHz 13
months earlier, in 1996 December. Aller et al. (2003) found strong
circular polarization, m_c_ = -0.23% +- 0.04%, at 4.8 GHz in integrated
measurements with the University of Michigan Radio Astronomy Observatory
(UMRAO) during the period 2001-2002.

2. 2004ApJS..155...33S
Re:VSOP J0609-1542
The core, as seen in the VLBApls image, is now clearly resolved out
into two distinct components. Emission in the core region, as seen in
the VSOP image as well as higher frequency USNO ground images, is
mostly in an easterly direction. Lower resolution images show the jet
taking a more northeasterly tack farther from the core. The area
subtended by the core is less than 0.05 mas^2^.

3. 1999A&A...348..653S
Re:[HB89] 0607-157
0607-157 is close to a star of approximately the same magnitude at
position 6:9:41.1,-15:42:42.8. In fact many of the images of this field
could not be used because the seeing was such that the image of the star
and the QSO blended. This contaminates the centroiding and the
difference is consistent with a "pull" of the QSO image center towards
the star.

4. 1996A&A...308..415B
Re:[HB89] 0607-157
0607-157: core-jet structure. The angular extension of the jet is about the
same at all three epochs, but the core and jet components are brighter at
epoch 3. Fig. 9 shows the amplitudes in position angle 90^deg^ from epoch 3
and epoch 2.5. In this plot a minimum is clearly visible at about
10 M{lambda}. It is slightly displaced between the two epochs, and corresponds
to a separation, at position angle 90^deg^, of {theta}_90^deg^_ ~10 mas for
epoch 3 and {theta}_90^deg^_ ~8.6 mas for epoch 2.5. This implies a proper
motion of {mu} ~0.3 mas/year. The parameters in Table 3 indicates this proper
motion with a new component N separated by about 9 mas at p.a. 59^deg^. In the
previous observations it was not considered to be separate from the C
component.

5. 1978MNRAS.185..149H
Re:[HB89] 0607-157
0607-157
This was a difficult observation, despite 1 arcsec seeing, due to the
proximity (3.7 arcsec) of the neighbouring red object to the southeast. The
two objects are blended on the Palomar Sky Survey. The identified NW member
appears neutral in colour and is probably stellar. An attempted spectrographic
observation of these objects by Wills & Wills (1976) showed only the red
object with a stellar spectrum and Mg I absorption. Wills & Wills estimate
that the neutral stellar object was >~20 mag at 1974.2, about 2 mag fainter
than on the Sky Survey and they suggest it as the identification. Our scanner
magnitude of 20.2 for epoch 1976.9 confirms the optical variability of
0607-157. This object is also a well-known radio variable (Altschuler & Wardle
1976).

6. 1976ApJS...31..143W
Re:[HB89] 0607-157
0607-157: Wills, Wills, and Douglas (1973) mention that on the Sky Survey
prints there are two objects; the north-preceding is neutral, the
south-following is red, and they have roughly the same apparent magnitudes
there. At the telescope (1974 February) only one object was seen; its spectrum
appears stellar, with Mg I absorption. An image-tube plate with a scale of
25" mm^-1^ (2.7 times larger than the Sky Survey scale), taken a few nights
later in good seeing, also shows only one, the south-following object. It is
interesting to note that the radio source is rapidly variable (Dent, Kapitzky,
and Kojoian 1974; Altschuler and Wardle, private communication), and we
suggest that the north-preceding NSO of the pair discussed by Wills, Wills,
and Douglas (1973) is the source identification, and is optically variable
(17-18 mag on the Sky Survey, >~20 mag in 1974.2).


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