English

EMU Detection of a Large and Low Surface Brightness Galactic SNR G288.8-6.3

High Energy Astrophysical Phenomena 2023-08-21 v1 Astrophysics of Galaxies

Abstract

We present the serendipitous detection of a new Galactic Supernova Remnant (SNR), G288.8-6.3 using data from the Australian Square Kilometre Array Pathfinder (ASKAP)-Evolutionary Map of the Universe (EMU) survey. Using multi-frequency analysis, we confirm this object as an evolved Galactic SNR at high Galactic latitude with low radio surface brightness and typical SNR spectral index of α=0.41±0.12\alpha = -0.41\pm0.12. To determine the magnetic field strength in SNR G288.8-6.3, we present the first derivation of the equipartition formulae for SNRs with spectral indices α>0.5\alpha>-0.5. The angular size is 1. ⁣8×1. ⁣61.\!^\circ 8\times 1.\!^\circ 6 (107. ⁣6×98. ⁣4)(107.\!^\prime 6 \times 98.\!^\prime 4) and we estimate that its intrinsic size is 40\sim40pc which implies a distance of 1.3\sim1.3kpc and a position of 140\sim140pc above the Galactic plane. This is one of the largest angular size and closest Galactic SNRs. Given its low radio surface brightness, we suggest that it is about 13000 years old.

Keywords

Cite

@article{arxiv.2308.08716,
  title  = {EMU Detection of a Large and Low Surface Brightness Galactic SNR G288.8-6.3},
  author = {Miroslav D. Filipović and Shi Dai and Bojan Arbutina and Natasha Hurley-Walker and Robert Brose and Werner Becker and Hidetoshi Sano and Dejan Urošević and T. H. Jarrett and Andrew M. Hopkins and Rami Z. E. Alsaberi and R. Alsulami and Cristobal Bordiu and Brianna Ball and Filomena Bufano and Christopher Burger-Scheidlin and Evan Crawford and Jayanne English and Frank Haberl and Adriano Ingallinera and Anna D. Kapinska and Patrick J. Kavanagh and Bärbel S. Koribalski and Roland Kothes and Sanja Lazarević and Jonathan Mackey and Gavin Rowell and Denis Leahy and Sara Loru and Peter J. Macgregor and Luciano Nicastro and Ray P. Norris and Simone Riggi and Manami Sasaki and Milorad Stupar and Corrado Trigilio and Grazia Umana and Tessa Vernstrom and Branislav Vukotić},
  journal= {arXiv preprint arXiv:2308.08716},
  year   = {2023}
}

Comments

Accepted for publication in The Astrophysical Journal