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arXiv · 1707.04700

Measuring the X-shaped structures in edge-on galaxies

S. S. Savchenko·N. Ya. Sotnikova·A. V. Mosenkov·V. P. Reshetnikov·D. V. Bizyaev
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Abstract

We present a detailed photometric study of a sample of 22 edge-on galaxies with clearly visible X-shaped structures. We propose a novel method to derive geometrical parameters of these features, along with the parameters of their host galaxies based on the multi-component photometric decomposition of galactic images. To include the X-shaped structure into our photometric model, we use the IMFIT package, in which we implement a new component describing the X-shaped structure. This method is applied for a sample of galaxies with available SDSS and Spitzer IRAC 3.6 $μ$m observations. In order to explain our results, we perform realistic $N$-body simulations of a Milky Way-type galaxy and compare the observed and the model X-shaped structures. Our main conclusions are as follows: (1) galaxies with strong X-shaped structures reside in approximately the same local environments as field galaxies; (2) the characteristic size of the X-shaped structures is about 2/3 of the bar size; (3) there is a correlation between the X-shaped structure size and its observed flatness: the larger structures are more flattened; (4) our $N$-body simulations qualitatively confirm the observational results and support the bar-driven scenario for the X-shaped structure formation.

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S. S. Savchenko, N. Ya. Sotnikova, A. V. Mosenkov, V. P. Reshetnikov, D. V. Bizyaev. 2017-07-15. Measuring the X-shaped structures in edge-on galaxies. https://doi.org/10.1093/mnras%2Fstx1802

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