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ASKAP is playing a pivotal role in FRB localisations, enabling the
identification of their host galaxies. The Very Large Telescope (VLT)
has been used to image the host galaxies of ASKAP FRBs. The four precisely localised busts
came from the outskirts of their host galaxies, ruling out models
involving supermassive black holes. Additional follow-up observations
conducted with optical telescope such as Keck II and Gemini South
established the distance to the host galaxies and studied properties
such as colour magnitudes, mass, size and star formation rate. All
four FRB hosts are massive galaxies, roughly the same size as the
Milky Way and moderately making stars. Radio follow-up observations
using the the Australia Compact Array Telescope (ATCA) and Very Large
Array (VLA) studied the radio environment of these FRBs in their host
galaxies and found that none were embedded in a dense radio
nebula. Thus, FRBs can originate in more diverse environments than
previously thought. Some earlier work suggested that most FRBs could
be a by-product of a special class of exploding stars known as
'super-luminous supernovae' that are mainly found in very small
'dwarf' galaxies. This latest research shows that while one FRB (the
'repeating' FRB 121102) is known to lie in a dwarf galaxy, this is
rather unusual in terms of the general FRB population.
More details are given in
the paper by Bhandari et al.,
published in Astrophysical Journal Letters.
(Image credit: Sam Moorfield)
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