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Cosmic: Microarcsecond Resolution with a 30 Meter Radio Telescope


McCulloch, PM and Ellingsen, SP and Jauncey, DL and Carter, SJB and Cimo, G and Lovell, JEJ and Dodson, R, Cosmic: Microarcsecond Resolution with a 30 Meter Radio Telescope, The Astronomical Journal, 129, (4) pp. 2034-2040. ISSN 0004-6256 (2005) [Refereed Article]

DOI: doi:10.1086/428374


Interstellar scintillation has been conclusively demonstrated to be the principal cause of the intraday variability (IDV) observed in the centimeter-wavelength emission of many active galactic nuclei. A few sources show large amplitude modulation in their flux density on a timescale of hours. However, the majority of IDV sources exhibit variability on timescales of a day or more. Some sources have been found to show an annual cycle in the pattern of their variability. Such an annual cycle occurs because the relative speeds of the Earth and the interstellar medium change as the Earth orbits the Sun. To search for these annual variations, as well as to follow the source evolution, requires a dedicated instrument; the necessary amounts of observing time are beyond the capability of the National Facility instruments. Here we describe the scientific motivation for and present an outline of the COSMIC (Continuous Single-Dish Monitoring of Intraday Variability at Ceduna) project, which uses the University of Tasmania's 30m diameter radio telescope at Ceduna, which has been monitoring the flux density of a number of the stronger southern scintillators at 6.65 GHz since 2003 March. © 2005. The American Astronomical Society. All rights reserved.

Item Details

Item Type:Refereed Article
Research Division:Physical Sciences
Research Group:Astronomical sciences
Research Field:Galactic astronomy
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the physical sciences
UTAS Author:McCulloch, PM (Professor Peter McCulloch)
UTAS Author:Ellingsen, SP (Professor Simon Ellingsen)
UTAS Author:Carter, SJB (Dr Steven Carter)
UTAS Author:Cimo, G (Mr Giuseppe Cimo)
UTAS Author:Dodson, R (Mr Richard Dodson)
ID Code:32630
Year Published:2005
Web of Science® Times Cited:21
Deposited By:Engineering
Deposited On:2005-08-01
Last Modified:2007-11-06

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