Proposal code

w059

Proposal title

A Complete Sample of Strong Extragalactic Intra-Day Variable Sources.

The

Investigators and their

Affiliations

P.I. L. L. Kedziora-Chudczer RCfTA, Sydney University \& ATNF, Australia
D.L. Jauncey, J.E. Reynolds ATNF, Australia
A.K. Tzioumis, M.H. Wieringa ATNF, Australia
G.D. Nicolson, J.F.H.Quick HartRAO, SOUTH AFRICA
M.A. Walker RCfTA, Sydney University, Australia
P.M. McCulloch, M.E. Costa University of Tasmania, Australia
R.A. Preston, D.L. Meier, D.W. Murphy JPL, USA
S.J. Tingay, D.L. Jones JPL, USA
P.G. Edwards, J.E.J. Lovell ISAS, JAPAN

Proposal Abstract

We propose to image at 5 GHz and at two epochs, the ten strong compact, flat-spectrum, high-amplitude, intra-day variable Parkes sources that we have discovered in our IDV Survey. We specifically wish to constrain the models and Doppler factors for the radiating material through a determination of (or limits to) the brightness temperatures and the determination of structural changes, particularly in the core, between the two epochs. We plan to follow the total flux density variability with ground-based monitoring during the course of the VSOP observations, since these sources can vary by up to 50\ flux density monitoring is essential to separate intensity changes that occur during the course of one HALCA observation from apparent structure. Regardless of whether the observed flux density variations are due to intrinsic or extrinsic mechanisms, these IDV sources are likely to possess the smallest angular size and hence the highest brightness temperatures of any extragalactic radio sources known. As such, the VSOP observations proposed here are essential for the planning for future Space VLBI missions.

The full Cover Sheets (compressed post-script, typically 50kbytes) can be retrieved. Note that many proposals were reduced in extent by the Scientific Review Committee (e.g. by reducing the number of experiments), however the Cover Sheets contain the full proposal as submitted. Also note that AO2 proposals were submitted in May 1998, and information such as affiliations and contact details has changed for some proposers since that time. The Cover Sheets (and the details on this page, which were derived from the Cover Sheets) may therefore have changed.