30th of January 2019 |
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A (relatively) nearby Fast Radio Burst |
by Petroff et al. |
Fast radio bursts (FRBs) are millisecond pulses of radio emission that
appear to have extragalactic origins. More than 50 FRBs have now been
detected, with only one seen to repeat. Petroff et al. have recently
discovered a new FRB in archival Parkes data from the high-latitude
portion of the High Time Resolution Universe South survey. FRB 110214
has one of the lowest dispersion measures of any known FRB (DM = 169
pc/cm^3), and was detected in two beams of the Parkes multibeam
receiver. A triangulation of the burst origin on the sky identified
three possible regions in the beam pattern where it may have
originated, all in sidelobes of the primary detection beam. Depending
on the true location of the burst the intrinsic fluence is estimated
to fall in the range of 50--2000 Jy ms, making FRB 110214 one of the
highest fluence FRBs detected with the Parkes telescope. No repeating
pulses were seen in almost 100 hours of follow-up observations.
The image above shows the dynamic spectrum of FRB 110214 detected in Beam 2 of the Parkes multibeam receiver. The effects of dispersion have been removed and the integrated timeseries are shown over the top half (top), the bottom half (middle), and the entire range (bottom) of the bandwidth. The frequency channels between 1522 − 1582 MHz have been masked in both beams due to persistent RFI. The lack of a strong signal in the top half of the band may be intrinsic to the burst, or due to Galactic scintillation, though the fact that the source location is far off-axis may also contribute. More details are given in the paper published in Monthly Notices of the Royal Astronomical Society. |