Dodson, R.

The future of cm and m-wave astronomy lies with the Square Kilometre Array (SKA), a telescope under development by a consortium of 17 countries. The SKA will be 50 times more sensitive than any existing radio facility. A majority of the key science for the SKA will be addressed through large-area imaging of the Universe at frequencies from 300 MHz to a few GHz.

The Australian SKA Pathfinder (ASKAP) is aimed squarely in this frequency range, and achieves instantaneous wide-area imaging through the development and deployment of phase-array feed systems on parabolic reflectors. This large field-of-view makes ASKAP an unprecedented synoptic telescope poised to achieve substantial advances in SKA key science.

The central core of ASKAP will be located at the Murchison Radio Observatory in inland Western Australia, one of the most radio-quiet locations on the Earth and one of the sites selected by the international community as a potential location for the SKA. Following an introductory description of ASKAP, this document contains 7 chapters describing specific science programmes for ASKAP.

In summary, the goals of these programmes are as follows

The detection of a million galaxies in atomic hydrogen emission across 75% of the sky out to a redshift of 0.2 to understand galaxy formation and gas evolution in the nearby Universe.

The detection of synchrotron radiation from 60 million galaxies to determine the evolution, formation and population of galaxies across cosmic time and enabling key cosmological tests.

The detection of polarized radiation from over 500,000 galaxies, allowing a grid of rotation measures at 10′ to explore the evolution of magnetic fields in galaxies over cosmic time.

The understanding of the evolution of the interstellar medium of our own Galaxy and the processes that drive its chemical and physical evolution.

The high-resolution imaging of intense, energetic phenomena by enlarging the Australian and global Very Long Baseline networks.

The discovery and timing of a thousand new radio pulsars.

The characterization of the radio transient sky through detection and monitoring of transient sources such as gamma ray bursts, radio supernovae and intra-day variables.

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The Mauritius Radio Telescope (MRT) has been built with the main objective of surveying the southern sky at meter wavelengths. MRT is a Fourier synthesis, T-shaped non-coplanar array. It consists of a2048 m long East-West arm with 1024 fixed helices and a 880 m long South arm with 15 trolleys. Each trolley has four helices. A 512 channel, 2-bit 3-level complex correlation receiver is used to process the data from the EW and S group outputs. At least 60 days of observing are required for obtaining the Fourier components of the brightness distribution of the sky required to complete the survey. The MRT survey will be one of the most extensive survey at low frequencies providing a moderately deep radio catalog reaching a source density of about 2 × 10⁴ sr^-1 over most of the sky south of δ=-10^°with an angular resolution of 4' × 4.6' sec (δ) and a limiting flux density of 200 mJy (3 σ level) at 151 MHz. This paper will describe the telescope, the observations carried out so far, challenges of imaging with the data acquired over a period exceeding four years with a non-coplanar array, and summarises the results obtained so far.

A new, meter-wave radio telesco