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G359.87+0.18: A Young SNR Candidate Near the Galactic Center?

F. Yusef-Zadeh·W. D. Cotton·S. P. Reynolds
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Abstract

Sub-arcsecond radio continuum observations of the Galactic center region at $λ$6 and 2cm reveal a 0.5$^{\prime\prime}$ diameter source with a shell-like morphology. This source is linearly polarized at a level of 16% at $λ$6cm and has a steep nonthermal spectrum with spectral index 1.6 between $λ$6 and 2 cm. The distance to this source is not known but the large rotation measure value of 3000 rad m$^{-2}$ suggests that G359.87+0.18 is likely to be located in the inner Galaxy or at an extragalactic distance. We discuss possible interpretations of this object as a recent supernova, a very young supernova remnant, a nova remnant, or an extragalactic source. All possibilities are highly problematic.

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F. Yusef-Zadeh, W. D. Cotton, S. P. Reynolds. 1998-02-27. G359.87+0.18: A Young SNR Candidate Near the Galactic Center?. https://doi.org/10.1086/311294

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