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arXiv · 1907.12593

The Next Generation Fornax Survey (NGFS): VI. The Alignment of Dwarf Galaxies in The Fornax Cluster

Yu Rong·Thomas H. Puzia·Paul Eigenthaler·Yasna Ordenes-Briceno·Matthew A. Taylor·Roberto P. Munoz·Hongxin Zhang·Gaspar Galaz·Karla Alamo-Martinez·Karen X. Ribbeck·Evak. Grebel·Simon Angel·Patrick Cote·Laura Ferrarese·Michael Hilker·Steffen Mieske·Bryan W. Miller·Ruben Sanchez-Janssen·Evelyn J. Johnston
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Abstract

Using the photometric data from the Next Generation Fornax Survey, we find a significant radial alignment signal among the Fornax dwarf galaxies. For the first time, we report that the radial alignment signal of nucleated dwarfs is stronger than that of non-nucleated ones at 2.4$\sigma$ confidence level, and the dwarfs located in the outer region ($R>R_{\rm{vir}}/3$; $R_{\rm{vir}}$ is the Fornax virial radius) show slightly stronger radial alignment signal than those in the inner region ($R<R_{\rm{vir}}/3$) at $1.5\sigma$ level. We also find that the significance of radial alignment signal is independent of the luminosities or sizes of the dwarfs.

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Yu Rong, Thomas H. Puzia, Paul Eigenthaler, Yasna Ordenes-Briceno, Matthew A. Taylor, Roberto P. Munoz, Hongxin Zhang, Gaspar Galaz, Karla Alamo-Martinez, Karen X. Ribbeck, Evak. Grebel, Simon Angel, Patrick Cote, Laura Ferrarese, Michael Hilker, Steffen Mieske, Bryan W. Miller, Ruben Sanchez-Janssen, Evelyn J. Johnston. 2019-07-29. The Next Generation Fornax Survey (NGFS): VI. The Alignment of Dwarf Galaxies in The Fornax Cluster. https://doi.org/10.3847/1538-4357/ab3725

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