Journal article
Low radio frequency observations and spectral modelling of the remnant of Supernova 1987A
JR Callingham, BM Gaensler, G Zanardo, L Staveley-Smith, PJ Hancock, N Hurley-Walker, ME Bell, KS Dwarakanath, TMO Franzen, L Hindson, M Johnston-Hollitt, A Kapińska, BQ For, E Lenc, B McKinley, J Morgan, AR Offringa, P Procopio, RB Wayth, C Wu Show all
Monthly Notices of the Royal Astronomical Society | OXFORD UNIV PRESS | Published : 2016
Abstract
We present Murchison Widefield Array observations of the supernova remnant (SNR) 1987A between 72 and 230 MHz, representing the lowest frequency observations of the source to date. This large lever arm in frequency space constrains the properties of the circumstellar medium created by the progenitor of SNR 1987A when it was in its red supergiant phase. As of late 2013, the radio spectrum of SNR 1987A between 72 MHz and 8.64 GHz does not show any deviation from a non-thermal power law with a spectral index of -0.74 ± 0.02. This spectral index is consistent with that derived at higher frequencies, beneath 100 GHz, and with a shock in its adiabatic phase. A spectral turnover due to free-free ab..
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Awarded by Australian Research Council
Awarded by Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)
Awarded by STFC
Funding Acknowledgements
JRC wishes to thank Peter Tuthill for useful discussions about the composition of red supergiant winds, and acknowledges the support of the Australian Postgraduate Award. BMG acknowledges the support of the Australian Research Council through grant FL100100114. The Dunlap Institute is funded through an endowment established by the David Dunlap family and the University of Toronto. This scientific work makes use of the Murchison Radio-astronomy Observatory, operated by CSIRO. We acknowledge the Wajarri Yamatji people as the traditional owners of the Observatory site. Support for the operation of the MWA is provided by the Australian Government Department of Industry and Science and Department of Education (National Collaborative Research Infrastructure Strategy: NCRIS), under a contract to Curtin University administered by Astronomy Australia Limited. We also acknowledge the iVEC Petabyte Data Store and the Initiative in Innovative Computing and the CUDA Center for Excellence sponsored by NVIDIA at Harvard University. This research was conducted by the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO), through project number CE110001020. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO.