Author/Authors :
S.J. Tingay، نويسنده , , D.L. Jauncey، نويسنده , , J.E. Reynolds، نويسنده , , A.K. Tzioumis، نويسنده , , E.A. King، نويسنده , , R.A. Preston، نويسنده , , D.W. Murphy، نويسنده , , D.L. Meier، نويسنده , , P.G. Edwards، نويسنده , , J.E.J. Lovell، نويسنده , , H. Hirabayashi، نويسنده , , H. Kobayashi، نويسنده , , K.M. Shibata، نويسنده , , P.M. McCulloch، نويسنده , , M.E. Costa، نويسنده , , P. Dewdney، نويسنده , , Grant W. Cannon، نويسنده , , G. Nicolson، نويسنده , , E. Valtaoja، نويسنده ,
Abstract :
We present the first results from our VSOP proposal, “γ-ray loud and quiet AGN with VSOP and SHEVE at 5 GHz”. This project is aimed at determining what, if anything, differentiates γ-ray-identified radio sources from similar strong, flat-spectrum radio sources which have not been identified as sources of greater than 100 MeV γ-rays. Five VSOP observations have been successfully completed as part of this project during VSOP AO1. One observation has been correlated thus far, a 4.970 GHz observation of PKS 0637-752 from 1997 November 21. We present the VSOP image for PKS 0637-752 and make comparisons between the space VLBI image and ground-based VLBI and Australia Telescope Compact Array (ATCA) images, as well as present ATCA flux density monitoring at 4.8 GHz. A brightness temperature for PKS 0637-752 of 0.7 × 1012 K has been determined from the VSOP data and a tentative apparent superluminal speed, from comparison to the ground-based VLBI image, of ∼9c.
