The Streams of the Gaping Abyss: A population of entangled stellar streams surrounding the Inner Galaxy. (arXiv:1901.07566v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Ibata_R/0/1/0/all/0/1">Rodrigo Ibata</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Malhan_K/0/1/0/all/0/1">Khyati Malhan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Martin_N/0/1/0/all/0/1">Nicolas Martin</a>
We present the discovery of a large population of stellar streams that
surround the inner Galaxy, found in the Gaia DR2 catalog using the new
STREAMFINDER algorithm. Here we focus on the properties of eight new
high-significance structures found at Heliocentric distances between 1 and 10
kpc and at Galactic latitudes $|b|>20deg$, named Slidr, Sylgr, Ylgr,
Fimbulthul, Sv”ol, Fj”orm, Gj”oll and Leiptr. Spectroscopic measurements of
seven of the streams confirm the detections, which are based on Gaia astrometry
and photometry alone, and show that these streams are predominantly metal-poor.
The sample possesses diverse orbital properties, although most of the streams
appear to be debris of inner-halo globular clusters. Many more candidate
streams are visible in our maps, but require follow-up spectroscopy to confirm
their nature. We also explain in detail the workings of the algorithm, and
gauge the incidence of false detections by running the algorithm on a smooth
model of the Gaia catalog.
We present the discovery of a large population of stellar streams that
surround the inner Galaxy, found in the Gaia DR2 catalog using the new
STREAMFINDER algorithm. Here we focus on the properties of eight new
high-significance structures found at Heliocentric distances between 1 and 10
kpc and at Galactic latitudes $|b|>20deg$, named Slidr, Sylgr, Ylgr,
Fimbulthul, Sv”ol, Fj”orm, Gj”oll and Leiptr. Spectroscopic measurements of
seven of the streams confirm the detections, which are based on Gaia astrometry
and photometry alone, and show that these streams are predominantly metal-poor.
The sample possesses diverse orbital properties, although most of the streams
appear to be debris of inner-halo globular clusters. Many more candidate
streams are visible in our maps, but require follow-up spectroscopy to confirm
their nature. We also explain in detail the workings of the algorithm, and
gauge the incidence of false detections by running the algorithm on a smooth
model of the Gaia catalog.
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