Mileura Wide-Field Array Science and Technology Demonstrator

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LonsdaleAST 0457585This award will be used to apply the design of low frequency radio astronomy technologies, developed at MIT under a previous NSF grant, to the construction of the Mileura Widefield Array-Low Frequency Demonstrator (MWA-LFD). The MWA-LFD is a collaboration of the Massachusetts Institute of Technology (MIT), Harvard-Smithsonian Center for Astrophysics (CfA), the Australian University Consortium, the Australian Telescope National Facility (ATNF), and the Western Australia government. The MWA-LFD will be located at the Mileura radio quiet site in the Western Australian desert. This scientifically capable array, consisting of 500 phased-array antennas feeding sophisticated digital signal processing systems, will have high sensitivity, broad 80-300 MHz frequency coverage, very high spectral and temporal resolution, electronic pointing agility and multi-beaming capability. Most importantly, it will feature an inherently very wide ~30 degrees instantaneous field of view. This combination of properties allows the demonstration array to perform cutting-edge science experiments with much better sensitivity than any existing instrument. This science capability will be available two years after the start of funding, and the last two years of the program will focus on science investigations with the array.The science goals of the MWA-LFD are in three main areas of investigation. The highest priority is to detect and characterize redshifted neutral atomic hydrogen (HI) signals from the cosmological Epoch of Reionization. The array will be capable of measuring the power spectrum of fluctuations, as well as imaging structures created by Stromgren spheres around quasars at redshifts with z~6.5, providing the first view of the cosmic dark ages. and early structure formation in the Universe. Second, the wide field capabilities of the array will be exploited to perform a blind search for transient sources of radio emission which is 6 orders of magnitude more sensitive than any previous work in this frequency range. Third, the array will be used to probe the heliosphere with unprecedented precision using interplanetary scintillation (IPS) and Faraday rotation techniques. The Faraday rotation holds the unique promise of constraining the orientation of the magnetic field in coronal mass ejection (CME) events, which is essential for predicting the impact of solar storms on the earth. Several other scientific topics, such as pulsar studies, solar bursts, the local structure of the interstellar medium, and radio recombination lines, can also be effectively addressed with the array.The MWA-LFD will demonstrate a broad range of technologies and techniques that are essential for the future feasibility and performance of full-scale wide field arrays that are currently in a conceptual stage of development. The MWA-LFD is relevant to cyber-infrastructure and cyber-science initiatives in the development of an astronomical telescope with no moving parts, all "actions" are handled electronically, and in the demonstration of new data handling techniques, involving massive, near real-time processing and preliminary analysis, followed by data compression. The application of the MWA-LFD to heliospheric measurements will make an important contribution to the National Space Weather Program, and thus will have valuable societal benefits. The project will be executed by multiple national and international partners, which offer opportunities for student exchange, and promotion of international scientific relations. The grant will train postdoctoral researchers and graduate students, and will engage undergraduate students and teachers in the project at no cost to the grant, through existing Research Experiences for Undergraduates (REU) and Research Experiences for Teachers (RET) programs at MIT and the Harvard-Smithsonian Center for Astrophysics (CfA). There will be extensive outreach activities to local area schools and communities.