HR: 0800h
AN: SH41A-1076    [Abstracts]
TI: Heliospheric Experiments Planned with the Mileura Widefield Array Demonstrator
AU: * Oberoi, D
EM: doberoi@haystack.mit.edu
AF: MIT Haystack Observatory, Off Route 40, Westford, MA 01886 United States
AU: Kasper, J C
EM: jck@space.mit.edu
AF: MIT Center for Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139 United States
AU: Salah, J E
EM: jes@haystack.mit.edu
AF: MIT Haystack Observatory, Off Route 40, Westford, MA 01886 United States
AU: Lonsdale, C J
EM: cjl@haystack.mit.edu
AF: MIT Haystack Observatory, Off Route 40, Westford, MA 01886 United States
AU: Cappallo, R J
EM: rjc@haystack.mit.edu
AF: MIT Haystack Observatory, Off Route 40, Westford, MA 01886 United States
AU: Morales, M
EM: mmorales@space.mit.edu
AF: MIT Center for Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139 United States
AU: Lazarus, A J
EM: ajl@space.mit.edu
AF: MIT Center for Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139 United States
AB: Low frequency radio telescopes, like the Mileura Widefield Array (MWA), are expected to grow into important tools for space weather and heliospheric studies because of their ability to conduct observations in the vast inner heliosphere and their potentially unique ability to constrain the heliospheric magnetic field. As a first step towards MWA a demonstrator array is being constructed at an exquisitely radio quiet site in Mileura, Western Australia. The demonstrator for the MWA will cover the frequency range from 80 to 300 MHz with 32 MHz bandwidth and will consist of ~500 stations, each comprising 16 dual polarization dipoles. The demonstrator will be 1.5 km in diameter, have a field of view of ~20 and 60 deg, and provide a resolution of 2.3 and 6.9 arcmin at 300 and 100 MHz respectively. It will have a collecting area of 8600 m$^2$ and a point source sensitivity of 0.03 Jy at 200 MHz (32 MHz bandwidth and 1 sec time integration). The primary backends of the demonstrator will be a Full Field of view Imager, which will provide a full polarization image of the entire field of view every second, and a beamformer capable of providing 8-16 independent beams per polarization which can be placed anywhere within the large field of view. The MWA demonstrator will have enough collecting area and sufficiently sophisticated backends to conduct significant scientific investigations. This paper will present the plans for heliospheric science applications planned for the demonstrator. These comprise Interplanetary Scintillations (IPS) and Faraday Rotation (FR) observations. IPS measurements yield information about the solar wind velocity, density and turbulence, and FR observations constrain the magnetic field strength and orientation in both the quiescent heliosphere and transients like Coronal Mass Ejections. The first scientific observations will be a survey of the southern skies to identify sources suitable for IPS and FR observations. IPS and FR observations of Coronal Mass Ejections and the quiescent heliosphere, and the subsequent analysis to estimate their plasma properties and magnetic field orientation will be conducted on a campaign basis.
DE: 6924 Interferometry
DE: 6954 Radio astronomy
DE: 6982 Tomography and imaging
DE: 6994 Instruments and techniques
DE: 2199 General or miscellaneous
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting