Letter to the Editor

VLBI observations of SN 2011dh: imaging of the youngest radio supernova

¹ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
e-mail: imartiv@mpifr-bonn.mpg.de
² Netherlands Institute for Radio Astronomy, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands
e-mail: tudose@astron.nl
³ Astronomical Institute of the Romanian Academy, Cutitul de Argint 5, 040557 Bucharest, Romania
⁴ Research Center for Atomic Physics and Astrophysics, Atomistilor 405, 077125 Bucharest, Romania
⁵ Joint Institute for VLBI in Europe, Postbus 2, 7990 AA Dwingeloo, The Netherlands
⁶ Dpt. Astronomia i Astrofísica, Univ. Valencia, C/ Dr. Moliner 50, 46100 Burjassot, Spain
⁷ Instituto de Astrofísica de Andalucía, CSIC, Apdo. Correos 3004, 18080 Granada, Spain
⁸ Universities Space Research Association, NSSTC, Huntsville, AL 35805, USA
⁹ Leiden Observatory, Leiden University, PO Box 9513, 2300RA Leiden, The Netherlands
¹⁰ Marquette University, Milwaukee, WI, USA
¹¹ Naval Research Laboratory, Washington DC, USA

Received: 3 October 2011
Accepted: 24 October 2011

Abstract

We report on the VLBI detection of supernova SN 2011dh at 22 GHz using a subset of the EVN array. The observations took place 14 days after the discovery of the supernova, thus resulting in a VLBI image of the youngest radio-loud supernova ever. We provide revised coordinates for the supernova with milli-arcsecond precision, linked to the ICRF. The recovered flux density is a factor  ~2 below the EVLA flux density reported by other authors at the same frequency and epoch of our observations. This discrepancy could be due to extended emission detected with the EVLA or to calibration problems in the VLBI and/or EVLA observations.