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arXiv · 1603.00983

The H$\alpha$ surface brightness $-$ radius plane as a diagnostic tool for photoionized nebulae

David J. Frew·Ivan S. Bojicic·Quentin A. Parker
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Abstract

The H$\alpha$ surface brightness $-$ radius ($S-r$) relation is a robust distance indicator for planetary nebulae (PNe), further enhanced by different populations of PNe having distinct loci in $S-r$ space. Other types of photoionized nebulae also plot in quite distinct regions in the $S-r$ plane, allowing its use as a diagnostic tool. In particular, the nova shells and massive star ejecta (MSE) plot on relatively tight loci illustrating their evolutionary sequences. For the MSE, there is potential to develop a distance indicator for these objects, based on their trend in $S-r$ space. As high-resolution, narrowband surveys of the nearest galaxies become more commonplace, the $S-r$ plane is a potentially useful diagnostic tool to help identify the various ionized nebulae in these systems.

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David J. Frew, Ivan S. Bojicic, Quentin A. Parker. 2016-03-03. The H$\alpha$ surface brightness $-$ radius plane as a diagnostic tool for photoionized nebulae. https://doi.org/10.1088/1742-6596%2F728%2F3%2F032015

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