Anish A. Roshi

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| The Murchison Widefield Array is a dipole-based aperture array synthesis telescope designed to operate in the 80–300 MHz frequency range. It is capable of a wide range of science investigations but is initially focused on three key science projects: detection and characterization of threedimensional brightness temperature fluctuations in the 21 cm line of(More)
The Murchison Widefield Array (MWA) is one of three Square Kilometre Array Precursor telescopes and is located at the Murchison Radio-astronomy Observatory in the Murchison Shire of the mid-west of Western Australia, a location chosen for its extremely low levels of radio frequency interference. The MWA operates at low radio frequencies, 80−300 MHz, with a(More)
The Murchison Widefield Array (MWA) is a Square Kilometre Array (SKA) Precursor. The telescope is located at the Murchison Radio–astronomy Observatory (MRO) in Western Australia (WA). The MWA consists of 4096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256(More)
We present the first spectroscopic images of solar radio transients from the prototype for the Murchison Widefield Array (MWA), observed on 2010 March 27. Our observations span the instantaneous frequency band 170.9– 201.6 MHz. Though our observing period is characterized as a period of ‘low’ to ‘medium’ activity, one broadband emission feature and numerous(More)
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will(More)
GLEAM, the GaLactic and Extragalactic All-sky MWA survey, is a survey of the entire radio sky south of declination +25◦ at frequencies between 72 and 231 MHz, made with the MWA using a drift scan method that makes efficient use of the MWA’s very large field-of-view. We present the observation details, imaging strategies, and theoretical sensitivity for(More)
A collaboration has been underway for the last several years to develop an L-band multipixel phased array feed for the Green Bank Telescope. These efforts will culminate in the deployment of a new wide-field observing instrument, Focal L-band Array for the GBT (FLAG).We report on progress on the cryogenic front end receiver system and real-time digital(More)
We present the results of an approximately 6,100 deg 104–196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the Murchison Widefield Array Commissioning Survey (MWACS). The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were(More)
We present a search for transient and variable radio sources at 154 MHz with the Murchison Widefield Array 32-tile prototype. Fifty-one images were obtained that cover a field of view of 1430 deg centred on Hydra A. The observations were obtained over three days in 2010 March and three days in 2011 April and May. The mean cadence of the observations was 26(More)