FRB 150418: clues to its nature from European VLBI Network and e-MERLIN observations
Artikel i vetenskaplig tidskrift, 2016

Aims: We investigate the nature of the compact and possibly variable nuclear radio source in the centre of WISE J0716-19, the proposed host galaxy of the fast radio burst FRB 150418. Methods: We observed WISE J0716-19 at 5.0 GHz with the European VLBI Network (EVN) four times between 2016 March 16 and June 2. At three epochs, we simultaneously observed the source with e-MERLIN at the same frequency. Results: We detected a compact source in the EVN data in each epoch with a significance of up to ~8σ. The four epochs yielded consistent results within their uncertainties for the peak surface intensity and positions. The mean values for these quantities are Ipeak = (115 ± 9)μJy beam-1 and RA = 07h16m34.55496(7)s, Dec = -19°00'39.4754(8)''. The e-MERLIN data provided ~3-5σ detections at a position consistent with those of the EVN data. The emission on angular scales intermediate between the EVN and e-MERLIN is consistent with being null. The brightness temperature of the EVN core is Tb ≳ 108.5 K, close to the value previously required to explain the short-term radio variability properties of WISE J0716-19 in terms of interstellar scintillation. Conclusions: Our observations provide direct and independent evidence of a nuclear compact source in WISE J0716-19, a physical scenario without evident connection with FRB 150418. However, the EVN data do not indicate the variability observed with the VLA.

galaxies: active / galaxies: individual: WISE J071634.59-190039.2 / radio continuum: galaxies / scattering


M. Ciroletti

Istituto Di Radioastronomia, Bologna

B. Marcote

Joint Institute for VLBI ERIC

M.A. Garrett

Netherlands Foundation for Research in Astronomy

Z. Paragi

Joint Institute for VLBI ERIC

Jun Yang

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

K. Hada

National Institutes of Natural Sciences - National Astronomical Observatory of Japan

T .W. B. Muxlow

University of Manchester

C.C. Cheung

Naval Research Laboratory

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 593 L16-L19 L16


Astronomi, astrofysik och kosmologi


Grundläggande vetenskaper


Onsala rymdobservatorium