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arXiv · 1702.02539

Absence of an X-shaped Structure in the Milky Way Bulge Using Mira Variable Stars

Martin Lopez-Corredoira
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Abstract

The stellar density distribution of the bulge is analyzed through one of its tracers. We use oxygen-rich Miras variables from the Catchpole et al. (2016) survey and OGLE-III survey as standard candles. The average age of these stars is around 9 Gyr. The population traced by Mira variables matches a boxy bulge prediction, not an X-shaped one, because only one peak is observed in the density along the analyzed lines of sight, whereas the prediction of an X-shape gives two clear peaks.

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Martin Lopez-Corredoira. 2017-02-08. Absence of an X-shaped Structure in the Milky Way Bulge Using Mira Variable Stars. https://doi.org/10.3847/1538-4357%2F836%2F2%2F218

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