| 1. |
- Booth, R. S., et al.
(författare)
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High-resolution observations of quasars from the Parkes +/- 4 deg. sample
- 1979
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Ingår i: Monthly notices of the Royal Astronomical Society. - Oxford : Oxford University Press. - 0035-8711 .- 1365-2966. ; 188, s. 159-163
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Tidskriftsartikel (refereegranskat)abstract
- VLBI observations of 20 compact quasars have been made between Jodrell Bank and Onsala at a frequency of 1666 MHz. Twelve of the quasars have inverted or peaked spectra at centimetre wavelengths and these are all unresolved, having angular diameters of less than 0.015 arcsec. Two out of five quasars with overall flat spectra are partially resolved on this scale size, as are three steep-spectrum quasars.
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| 2. |
- Chu, H.S., et al.
(författare)
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AO 0235+164 - A "Heretic" BL Lac
- 1994
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Ingår i: VLBI TECHNOLOGY. - Tokyo : Terra Scientific Publishing Company. ; , s. 146-155
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Bokkapitel (refereegranskat)
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| 3. |
- Stannard, D., et al.
(författare)
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VLBI Observations of 3C345 at 1.67 GHz
- 1980
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Ingår i: Monthly notices of the Royal Astronomical Society. - Oxford : Oxford University Press. - 0035-8711 .- 1365-2966. ; 192:4, s. 555-560
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Tidskriftsartikel (refereegranskat)abstract
- VLBI observations of the quasar 3C 345 suggest that the milliarcsec subcomponents in the core have approximately equal intensities at 1.67 GHz. A new compact feature is detected in the inner jet structure at a distance of ∼ 12 m.arcsec from the core. © 1980 Royal Astronomical Society. Provided by the NASA Astrophysics Data System
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| 4. |
- Zhang, F. J., et al.
(författare)
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1404+286 : A non-ideal calibrator for VLBI observations
- 1994
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Ingår i: Astronomy and Astrophysics. - Les Ulis : EDP Sciences. - 0004-6361 .- 1432-0746. ; 281:3, s. 649-652
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Tidskriftsartikel (refereegranskat)abstract
- The radio source 1404+286 was observed with global VLBI arrays at 5 and 1.67 GHz in 1990.88 and 1991.45 respectively. High quality maps are presented in this paper, and show the source to be resolved at both frequencies with a core-jet like structure extending approximately 6 mas in position angle approximately -145-degrees. The jet direction is similar in both maps. 1404+286 has often been used in the past as a flux density calibrator or a phase referencing source. Our results show that this source is not an ideal calibrator on VLBI scales.
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| 5. |
- Zhang, F.J., et al.
(författare)
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Are there two engines at the center of 3C 286?
- 1994
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Ingår i: Astronomy and Astrophysics. - Les Ulis : EDP Sciences. - 0004-6361 .- 1432-0746. ; 287:1, s. 32-37
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents images of the compact steep-spectrum quasar 3C 286 obtained with global VLBI arrays at 4.99 and 1.66 GHz. The morphology appears to be intermediate between the core-jet types and grossly distorted objects. The central portion is resolved into two components of almost equal peak brightnesses and spectral indices. On the 1.66 GHz map, the jet extends in position angle approximately -136-degrees, up to a knot (W1) (approximately 75 mas from the component C2) from which it curves rapidly towards the west to form another knot (W2). It is possible that the VLBI jet bends further towards the secondary component separated from the core by approximately 2.6'' in p.a. -115-degrees seen in high dynamic range VLA or Merlin maps. The jet has a sinuous feature shown clearly on the 5 GHz map. There is a low brightness extension at the North (designated N1) shown on both the 1.66 and 5 GHz maps, which is connected to the component C1 and bends towards the east.
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