High resolution rapid response observations of compact radio sources with the Ceduna Hobart Interferometer (CHI)
Context: Frequent, simultaneous observations across the electromagnetic spectrum are essential to the study of a range of astrophysical phenomena including active galactic nuclei. A key tool of such studies is the ability to observe an object when it flares i.e. exhibits a rapid and significant increase in its flux density.
Aims: We describe the specific observational procedures and the calibration techniques that have been developed and tested to create a single baseline radio interferometer that can rapidly observe a flaring object. This is the only facility that is dedicated to rapid high resolution radio observations of an object south of −30 degrees declination. An immediate application is to provide rapid contemporaneous radio coverage of AGN flaring at γ-ray frequencies detected by the Fermi Gamma-ray Space Telescope.
Methods: A single baseline interferometer, the Ceduna Hobart Interferometer (CHI), was formed with radio telescopes in Hobart, Tasmania and Ceduna, South Australia. A software correlator was set up at the University of Tasmania to correlate these data.
Results: Measurements of the flux densities of flaring objects can be made using our observing strategy within half an hour of a triggering event. These observations can be calibrated with amplitude errors better than 15%. Lower limits to the brightness temperatures of the sources can also be calculated using CHI.
History
Publication title
Astronomy & AstrophysicsVolume
538Article number
A150Number
A150Pagination
1-5ISSN
0004-6361Department/School
School of Natural SciencesPublisher
E D P SciencesPlace of publication
7, Ave Du Hoggar, Parc D Activites Courtaboeuf, Bp 112, Les Ulis Cedexa, France, F-91944Rights statement
Copyright 2012 ESORepository Status
- Open