Letter to the Editor

Collimated synchrotron threads linking the radio lobes of ESO 137-006

¹ Department of Physics and Electronics, Rhodes University, PO Box 94, Makhanda 6140, South Africa
e-mail: m.ramatsoku@ru.ac.za
² INAF – Osservatorio Astronomico di Cagliari, Via della Scienza 5, 09047 Selargius, CA, Italy
³ South African Radio Astronomy Observatory, 2 Fir Street, Black River Park, 7925 Observatory, South Africa
⁴ Argelander-Institut fur Astronomie, Auf dem Hugel 71, 53121 Bonn, Germany
⁵ ASTRON, Netherlands Institute for Radio Astronomy, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands
⁶ Department of Astronomy, University of Cape Town, Private Bag X3, 7701 Rondebosch, South Africa
⁷ Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen, The Netherlands
⁸ Department of Physics, University of Pretoria, Hatfield, Pretoria 0028, South Africa
⁹ Ruhr University Bochum, Faculty of Physics and Astronomy, Astronomical Institute, 44780 Bochum, Germany

Received: 23 February 2020
Accepted: 9 March 2020

Abstract

We present MeerKAT 1000 MHz and 1400 MHz observations of a bright radio galaxy in the southern hemisphere, ESO 137-006. The galaxy lies at the centre of the massive and merging Norma galaxy cluster. The MeerKAT continuum images (rms ∼0.02 mJy beam⁻¹ at ∼10″ resolution) reveal new features that have never been seen in a radio galaxy before: collimated synchrotron threads of yet unknown origin, which link the extended and bent radio lobes of ESO 137-006. The most prominent of these threads stretches in projection for about 80 kpc and is about 1 kpc in width. The radio spectrum of the threads is steep, with a spectral index of up to α ≃ 2 between 1000 and 1400 MHz.