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arXiv · 1903.07285

A tidal tale: detection of multiple stellar streams in the environment of NGC1052

Oliver Müller·R. Michael Rich·Javier Román·Mustafa K. Yıldız·Michal Bílek·Pierre-Alain Duc·Jérémy Fensch·Ignacio Trujillo·Andreas Koch
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Abstract

The possible existence of two dark matter free galaxies (NGC1052-DF2 and NGC1052-DF4) in the field of the early-type galaxy NGC1052 presents a challenge to theories of dwarf galaxy formation according to the current cosmological paradigm. We carried out a search for signatures of past interactions connected to the putative hosts of NGC1052-DF2 and NGC1052-DF4 using a very deep L-band image obtained with the 0.7m Jeanne Rich telescope that reach a surface brightness limit of 28.5 mag arcsec-2 in the r band. We found several low-surface brightness features, possibly consistent with an ongoing merger history in this group. We find a tidal interaction between NGC1052 and NGC1047, confirming a physical association. Furthermore we find a stellar loop around NGC1052 in the direction of NGC1042 and a stellar stream pointing in the direction of NGC1052-DF2 - but both are not directly connected. We find no evidence for a recent tidal interaction for NGC1052-DF2 and NGC1052-DF4. No low surface brightness features have been uncovered around the spiral galaxy NGC1042, which leaves the association (physical or projected) between NGC1052 and NGC1042 ambiguous, though they have similar radial velocities. Their association will only be established once accurate distances to both objects have been measured.

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Oliver Müller, R. Michael Rich, Javier Román, Mustafa K. Yıldız, Michal Bílek, Pierre-Alain Duc, Jérémy Fensch, Ignacio Trujillo, Andreas Koch. 2019-03-18. A tidal tale: detection of multiple stellar streams in the environment of NGC1052. https://doi.org/10.1051/0004-6361/201935463

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