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arXiv · 1908.09269

A Supernova Remnant Counterpart for HESS J1832-085

Nigel I. Maxted·M. D. Filipovic·N. Hurley-Walker·I. Bojicic·G. P. Rowell·F. Haberl·A. J. Ruiter·I. R. Seitenzahl·F. Panther·G. F. Wong·C. Braiding·M. Burton·G. Puhlhofer·H. Sano·Y. Fukui·M. Sasaki·W. Tian·H. Su·X. Cui·D. Leahy·P. J. Hancock
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Abstract

We examine the new Galactic supernova remnant (SNR) candidate, G23.11+0.18, as seen by the Murchison Widefield Array (MWA) radio telescope. We describe the morphology of the candidate and find a spectral index of -0.63+/-0.05 in the 70-170MHz domain. A coincident TeV gamma-ray detection in High-Energy Stereoscopic System (HESS) data supports the SNR nature of G23.11+0.18 and suggests that G23.11+0.18 is accelerating particles beyond TeV energies, thus making this object a promising new cosmic ray hadron source candidate. The remnant cannot be seen in current optical, infrared and X-ray data-sets. We do find, however, a dip in CO-traced molecular gas at a line-of-sight velocity of ~85 km/s, suggesting the existence of a G23.11+0.18 progenitor wind-blown bubble. Furthermore, the discovery of molecular gas clumps at a neighbouring velocity towards HESS J1832-085 adheres to the notion that a hadronic gamma-ray production mechanism is plausible towards the north of the remnant. Based on these morphological arguments, we propose an interstellar medium association for G23.11+0.18 at a kinematic distance of 4.6+/-0.8 kpc.

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Nigel I. Maxted, M. D. Filipovic, N. Hurley-Walker, I. Bojicic, G. P. Rowell, F. Haberl, A. J. Ruiter, I. R. Seitenzahl, F. Panther, G. F. Wong, C. Braiding, M. Burton, G. Puhlhofer, H. Sano, Y. Fukui, M. Sasaki, W. Tian, H. Su, X. Cui, D. Leahy, P. J. Hancock. 2019-08-25. A Supernova Remnant Counterpart for HESS J1832-085. https://doi.org/10.3847/1538-4357/ab3e3f

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