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arXiv · 1805.00017

The Maybe Stream: A Possible Cold Stellar Stream in the Ultra-Diffuse Galaxy NGC1052-DF2

Roberto Abraham·Shany Danieli·Pieter van Dokkum·Charlie Conroy·J. M. Diederik Kruijssen·Yotam Cohen·Allison Merritt·Jielai Zhang·Deborah Lokhorst·Lamiya Mowla·Jean Brodie·Aaron J. Romanowsky·Steven Janssens
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Abstract

We report tentative evidence for a cold stellar stream in the ultra-diffuse galaxy NGC1052-DF2. If confirmed, this stream (which we refer to as "The Maybe Stream") would be the first cold stellar stream detected outside of the Local Group. The candidate stream is very narrow and has an unusual and highly curved shape.

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Roberto Abraham, Shany Danieli, Pieter van Dokkum, Charlie Conroy, J. M. Diederik Kruijssen, Yotam Cohen, Allison Merritt, Jielai Zhang, Deborah Lokhorst, Lamiya Mowla, Jean Brodie, Aaron J. Romanowsky, Steven Janssens. 2018-04-30. The Maybe Stream: A Possible Cold Stellar Stream in the Ultra-Diffuse Galaxy NGC1052-DF2. https://arxiv.org/abs/1805.00017

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