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arXiv · 1203.4982

The remnant of Supernova 1987A resolved at 3 mm wavelength

Masha Lakicevic·Giovanna Zanardo·Jacco Th. van Loon·Lister Staveley-Smith·Toby Potter·C. -Y. Ng·B. M. Gaensler
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Abstract

The proximity of core-collapse Supernova 1987A (SN1987A) in the Large Magellanic Cloud (LMC) and its rapid evolution make it a unique case study of the development of a young supernova remnant. We aim at resolving the remnant of SN1987A for the first time in the 3-mm band (at 94 GHz). We observed the source at 3-mm wavelength with a 750-m configuration of the Australia Telescope Compact Array (ATCA). We compare the image with a recent 3-cm image and with archival X-ray images. We present a diffraction-limited image with a resolution of 0.7", revealing the ring structure seen at lower frequencies and at other wavebands. The emission peaks in the eastern part of the ring. The 3-mm image bears resemblance to early X-ray images (from 1999-2000). We place an upper limit of 1 mJy (2 σ) on any discrete source of emission in the centre (inside of the ring). The integrated flux density at 3 mm has doubled over the six years since the previous observations at 3 mm. At 3 mm - i.e. within the operational domain of the Atacama Large Millimeter/submillimeter Array (ALMA) - SN1987A appears to be dominated by synchrotron radiation from the inner rim of the equatorial ring, characterised by moderately-weak shocks. There is no clear sign of emission of a different nature, but the current limits do not rule out such component altogether.

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Masha Lakicevic, Giovanna Zanardo, Jacco Th. van Loon, Lister Staveley-Smith, Toby Potter, C. -Y. Ng, B. M. Gaensler. 2012-03-22. The remnant of Supernova 1987A resolved at 3 mm wavelength. https://doi.org/10.1051/0004-6361%2F201218902

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