Bhandari et al. present the detection of fast radio burst, FRB 191001,
during commensal observations conducted with the Australian Square
Kilometre Array Pathfinder (ASKAP) as part of the Commensal Real-time
ASKAP Fast Transients (CRAFT) survey. The sub-arcsecond localisation
of the FRB provided by ASKAP reveals that the burst originated in the
outskirts of a highly star-forming spiral in a galaxy pair at redshift
z=0.23. FRB 191001 is the brightest of the bursts localized to its
host galaxy by ASKAP to date. Although the FRB only lasted several
milli-seconds, it was so bright it was also detected as a transient in
the single 10-s snapshot image from the low-time-resolution
visibilities obtained simultaneously with CRAFT data. The image above
shows the dynamic spectrum (brightness as a function of frequency and
time) of FRB 191001. The data were coherently de-dispersed at the DM
of 508 pc/cm^3 measured for the burst. The scintillation bandwidth for
the burst (i.e., the range of frequency over which the burst changes
from faint to bright) is ∼600 kHz at 824 MHz, which is consistent with
predictions for diffractive scintillation induced by the interstellar
medium of our Milky Way Galaxy along this line of sight.
The paper will be published in Astrophysical Journal Letters.
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