Seminari:"On the origin of Fast Radio Bursts and sub-milliarcsecond localization"

Conferenciant: Dr. Benito Marcote (JIVE, Països Baixos)

Data/Hora: 18-10-2016, 12:00h

Lloc: Sala de Graus Eduard Fontseré

Contactejmparedes@ub.edu

Resum:            

Fast Radio Bursts (FRBs) are radio transient sources that emit a single pulse with a duration of only a few milliseconds. They were firstly discovered in 2007, and nowadays we have detected tens of these events. However, their physical origin remains completely unknown. Both, Galactic or extragalactic origins have been proposed. The observed pulses resemble the ones observed in pulsars, and thus preferring a Galactic origin. However, the large dispersion measures observed in these pulses point to an extragalactic origin. Only an accurate localization of these events would lead us to identify their counterparts and thus unveil the origin of the FRBs. Interferometric radio detections are thus required. Two different approaches are being conducted with the European VLBI Network (EVN): identify their possible afterglows and image the single pulses of the FRBs.

The second one presents important technical challenges and has never been done at the moment. We have performed a project to demonstrate its feasibility imaging single pulses from known pulsars and Rotating Radio Transients (RRATs). This project leads into a new EVN observing mode that can be used to reach milliarsecond astrometry on these objects (the localization of most RRATs is currently limited to few arcminutes).

Concerning the possible afterglows produced by FRBs, Keane et al. (2016) reported for the first time the localization of an FRB. A transient source coincident with the galaxy WISE J0716–1900 was observed right after the detection of FRB 150418. This association would confirm the extragalactic origin of the FRBs. However, these results have been widely discussed during the last months. We have monitored the associated galaxy, WISE J0716−1900, with the EVN in order to unveil its origin and its possible association with FRB 150418.