A polarized fast radio burst at low Galactic latitude

作者：Petroff E^*; Burke Spolaor S; Keane E F; McLaughlin M A; Miller R; Andreoni I; Bailes M; Barr E D; Bernard S R; Bhandari S; Bhat N D R; Burgay M; Caleb M; Champion D; Chandra P; Cooke J; Dhillon V S; Farnes J S; Hardy L K; Jaroenjittichai P; Johnston S; Kasliwal M; Kramer M; Littlefair S P; Macquart J P; Mickaliger M; Possenti A; Pritchard T; Ravi V; Rest A; Rowlinson A; Sawangwit U; Stappers B; Sullivan M; Tiburzi C

来源：Monthly Notices of the Royal Astronomical Society, 2017, 469(4): 4465-4482.

DOI：10.1093/mnras/stx1098

• polarization
• methods: data analysis
• surveys
• ISM: structure

We report on the discovery of a new fast radio burst (FRB), FRB 150215, with the Parkes radio telescope on 2015 February 15. The burst was detected in real time with a dispersion measure (DM) of 1105.6 +/- 0.8 pc cm(-3), a pulse duration of 2.8(-0.5)(+1.2) ms, and a measured peak flux density assuming that the burst was at beam centre of 0.7(-0.1)(+0.2) Jy. The FRB originated at a Galactic longitude and latitude of 24.66 degrees, 5.28 degrees and 25 degrees away from the Galactic Center. The burst was found to be 43 +/- 5 per cent linearly polarized with a rotation measure (RM) in the range -9 < RM < 12 rad m(-2) (95 per cent confidence level), consistent with zero. The burst was followed up with 11 telescopes to search for radio, optical, X-ray, gamma-ray and neutrino emission. Neither transient nor variable emission was found to be associated with the burst and no repeat pulses have been observed in 17.25 h of observing. The sightline to the burst is close to the Galactic plane and the observed physical properties of FRB 150215 demonstrate the existence of sight lines of anomalously low RM for a given electron column density. The Galactic RM foreground may approach a null value due to magnetic field reversals along the line of sight, a decreased total electron column density from the Milky Way, or some combination of these effects. A lower Galactic DM contribution might explain why this burst was detectable whereas previous searches at low latitude have had lower detection rates than those out of the plane.

• 出版日期2017-8
• 单位西北大学; 中国地震局; CSIRO