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arXiv · 1901.00762

Bar properties and photometry of barred low surface brightness disc galaxies

Wesley Peters·Rachel Kuzio de Naray
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Abstract

We measure the bar properties (length, strength, and corotation radius) of a sample of barred low surface brightness (LSBs) galaxies and compare to previous results for both LSBs and high surface brightness galaxy (HSBs) samples. In addition, we present new optical $\textit{B}$- and $\textit{I}$-band surface brightness profiles, magnitudes, and colours. We find that bars in LSBs are shorter and weaker when compared with those in HSBs galaxies. Based on analysis of four different bar length measures on simulated galaxy images, we find our bar length measure based on azimuthal light profiles is the most accurate out of the four tested here when seeing effects are taken into account. We also find that bars in LSBs have comparable relative bar pattern speeds to those in HSBs, the majority of which we find to be `fast' (i.e. $\mathcal{R} <$ 1.4). In general, we find that our barred LSBs have comparable central surface brightnesses and total magnitudes to unbarred LSBs, albeit slightly brighter. Our barred LSBs fall on a shallower disc scale length (h) vs $M_{B}^{T}$ relation than unbarred LSBs. Finally, we find our barred LSBs to be just as gas rich as unbarred LSBs (i.e. $M_{gas}/(M_{gas} + M_{*}) > 0.5$).

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Wesley Peters, Rachel Kuzio de Naray. 2019-01-03. Bar properties and photometry of barred low surface brightness disc galaxies. https://doi.org/10.1093/mnras%2Fsty3505

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