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arXiv · 2004.03203

Collimated synchrotron threads linking the radio lobes of ESO137-006

M. Ramatsoku·M. Murgia·V. Vacca·P. Serra·S. Makhathini·F. Govoni·O. Smirnov·L. A. L. Andati·E. de Blok·G. I. G. Józsa·P. Kamphuis·D. Kleiner·F. M. Maccagni·D. Cs. Molnár·A. J. T. Ramaila·K. Thorat·S. V. White
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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 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 $\alpha\simeq 2$ between 1000 MHz and 1400 MHz.

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M. Ramatsoku, M. Murgia, V. Vacca, P. Serra, S. Makhathini, F. Govoni, O. Smirnov, L. A. L. Andati, E. de Blok, G. I. G. Józsa, P. Kamphuis, D. Kleiner, F. M. Maccagni, D. Cs. Molnár, A. J. T. Ramaila, K. Thorat, S. V. White. 2020-04-07. Collimated synchrotron threads linking the radio lobes of ESO137-006. https://doi.org/10.1051/0004-6361/202037800

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