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arXiv · 1911.00009

Phase-space correlation in stellar streams of the Milky Way halo: The clash of Kshir and GD-1

Khyati Malhan·Rodrigo A. Ibata·Raymond G. Carlberg·Michele Bellazzini·Benoit Famaey·Nicolas F. Martin
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Abstract

We report the discovery of a 70-degree long stellar stream in the Milky Way halo, which criss-crosses the well known "GD-1" stream. We show that this new stellar structure ("Kshir") and GD-1 lie at similar distance, and are remarkably correlated in kinematics. We propose several explanations for the nature of this new structure and its possible association with GD-1. However, a scenario in which these two streams were accreted onto the Milky Way within the same dark matter sub-halo seems to provide a natural explanation for their phase-space entanglement, and other complexities of this coupled-system.

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Khyati Malhan, Rodrigo A. Ibata, Raymond G. Carlberg, Michele Bellazzini, Benoit Famaey, Nicolas F. Martin. 2019-10-31. Phase-space correlation in stellar streams of the Milky Way halo: The clash of Kshir and GD-1. https://doi.org/10.3847/2041-8213%2Fab530e

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