6th of March 2024 |
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ATNF Colloquium |
The Frontier in Low Frequency Radio Astrophysics from the Farside of the Moon |
Nivedita Mahesh (California Institute of Technology) |
Abstract:
The Farside Array for Radio Science Investigations of the Dark ages
and Exoplanets (FARSIDE) is a NASA Probe-class concept to place a
low-frequency radio interferometric array on the far side of the
Moon. FARSIDE will look for radio emissions from magnetospheres of
stars and exoplanets, which affect exoplanet habitability and serve as
a pathfinder for studying the Dark Ages of the Universe. The FARSIDE
architecture employs a novel design consisting of 128 pairs of
antennas and receiver nodes distributed over a 10 km × 10 km area in a
four-arm spiral configuration that will operate from 200 kHz to 40
MHz. I will present the planned mission architecture, array layout,
antenna packaging, and deployment trade study. In addition, this talk
will cover the projected performance and sensitivity of the array for
the two primary sciences cases. Given the novel deployment strategy
for the FARSIDE array, we have developed a forward modeling pipeline
to simulate its polarization performance. This lunar array concept is
developed a lot on the heritage of a similar low frequency telescope
on ground - the OVRO Long Wavelength Array. And I will briefly discuss
the current status and pipeline development efforts of the newly
upgraded OVRO-LWA. The talk will end with an overview of one of
humanities’ next “great” observatories - FarView - a NASA Innovative
Advanced Concepts. Farview will be an observatory built in-situ on the
lunar farside using materials from regolith.
The image above gives an overview of the proposed FARSIDE mission architecture. The central base station will be located in the lander and will provide the central processing, power, and communications. From the lander, there will be four two-wheeled axel rovers that will get deployed. The rovers in turn will have the tethers with antennas embedded in them. Inset images show the processing done to access the polarization performance of the planned array layout. A pure Stokes I input sky model is processed to the custom FARSIDE pipeline. The FARSIDE beam and array layout results in non-zero Stokes V images. There is considerable Stokes V leakage when there is a spatial offset. |