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We present new, low-frequency images of the powerful FR I radio galaxy Hydra A (3C 218). Images were made with the Very Large Array (VLA) at frequencies of 1415, 330, and 74 MHz, with resolutions on the order of 20. The morphology of the source is seen to be more complex and even larger than previously known, and extends nearly 8 (530 kpc) in a North-South direction. The southern lobe is bent to the east and extends in that direction for nearly 3 (200 kpc). In addition, we find that the northern lobe has a flatter spectral slope than the southern lobe, consistent with the appearance of greater confinement to the south. We measure overall spectral indices alpha^{330}_{74} = -0.83 and alpha^{1415}_{330} = -0.89.
The central region of the Galaxy has been observed at 580, 620 and 1010 MHz with the Giant Metrewave Radio Telescope (GMRT). We detect emission from Sgr-A*, the compact object at the dynamical centre of the Galaxy, and estimate its flux density at 62
We have used archival 74 MHz VLA data spanning the last 15 years in combination with new data from the Long Wavelength Demonstrator Array (LWDA) and data from the literature covering the last 50 years to explore the evolution of Cas A at low radio fr
We present a sample of 1,483 sources that display spectral peaks between 72 MHz and 1.4 GHz, selected from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey. The GLEAM survey is the widest fractional bandwidth all-sky su
Spectral variability of radio sources encodes information about the conditions of intervening media, source structure, and emission processes. With new low-frequency radio interferometers observing over wide fractional bandwidths, studies of spectral
The radio sky at lower frequencies, particularly below 20 MHz, is expected to be a combination of increasingly bright non-thermal emission and significant absorption from intervening thermal plasma. The sky maps at these frequencies cannot therefore