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

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.

5 pages, accepted for publication in ApJ

References in corpus (4)

• Modelling the Galactic bar using OGLE-II Red Clump Giant Stars
• The X-Shaped Milky Way Bulge in OGLE-III Photometry and in N-Body Models
• Common Origin of Two RR Lyrae Populations and the Double Red Clump in the Milky Way Bulge
• A case against an X-shaped structure in the Milky Way young bulge

Cited by in corpus (15)

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• HERBS I: Metallicity and alpha enhancement along the Galactic bulge minor axis
• Mira Variable Stars From LAMOST DR4 Data: Emission Features, Temperature Types, and Candidate Selection
• The structure of the Milky Way based on unWISE 3.4$\mu$m integrated photometry
• The VVV survey: Long-period variable stars I. Photometric catalog of ten VVV/OGLE tiles
• Age-morphology dependence of the Milky Way boxy/peanut bulge seen in Mira variables
• 3D Parameter Maps of Red Clump Stars in the Milky Way -- Absolute Magnitudes and Intrinsic Colors
• Distribution of red clump stars does not support the X-shaped Galactic bulge
• Analysing the structure of the bulge with Mira variables
• Blanco DECam Bulge Survey (BDBS) IV: Metallicity Distributions and Bulge Structure from 2.6 Million Red Clump Stars