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Related papers: The information content in cold stellar streams

200 papers

Stellar streams retain a memory of their gravitational interactions with small-scale perturbations. While perturbative models for streams have been formulated in action-angle coordinates, a direct transformation to these coordinates is only…

Stellar streams result from the tidal disruption of satellites and star clusters as they orbit a host galaxy, and can be very sensitive probes of the gravitational potential of the host system. We select and study narrow stellar streams…

Astrophysics of Galaxies · Physics 2017-03-08 Robyn E. Sanderson , Johanna Hartke , Amina Helmi

We use N-body simulations to model the tidal disruption of a star cluster in a Milky-Way-sized dark matter halo, which results in a narrow stream comparable to (but slightly wider than) Pal-5 or GD-1. The mean Galactic dark matter halo is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Wai-Hin Wayne Ngan , Raymond G. Carlberg

Nearly a hundred progenitor-less, thin stellar streams have been discovered in the Milky Way, thanks to Gaia and related surveys. Most streams are believed to have formed from star clusters and it was recently proposed that extended star…

Astrophysics of Galaxies · Physics 2025-02-24 Daniel Roberts , Mark Gieles , Denis Erkal , Jason L. Sanders

Simulations are run with and without a normal cold dark matter sub-halo population below 4x10^8 M_sun to examine the role of the lower mass sub-halos in the creation of density variations, "gaps", within thin tidal star streams. Dense star…

Astrophysics of Galaxies · Physics 2021-01-20 Raymond G. Carlberg

We present the results of fitting a flexible stellar stream density model to a collection of thirteen streams around the Milky Way, using photometric data from DES, DECaLS, and Pan-STARRS. We construct density maps for each stream and…

Astrophysics of Galaxies · Physics 2022-06-22 Jeffrey M. Patrick , Sergey E. Koposov , Matthew G. Walker

Upcoming ground and space-based surveys are poised to illuminate low surface brightness tidal features, providing a new observable connection to dark matter physics. From imaging of tidal debris, the morphology of stellar streams can be…

Astrophysics of Galaxies · Physics 2026-04-08 Jacob Nibauer , Sarah Pearson

Recent analyses of the Pal 5 and GD-1 tidal streams suggest that the inner dark matter halo of the Milky Way is close to spherical, in tension with predictions from collisionless N-body simulations of cosmological structure formation. We…

Astrophysics of Galaxies · Physics 2018-05-23 Biwei Dai , Brant E. Robertson , Piero Madau

Stellar streams, the debris of tidally disrupted satellites, trace their host's gravitational potential and thus probe dark matter halo structure. While six-dimensional phase-space data of Galactic streams enable precise dark matter halo…

Astrophysics of Galaxies · Physics 2026-01-27 David Chemaly , Elisabeth Sola , Vasily Belokurov , Sergey Koposov , GyuChul Meyong , HanYuan Zhang , Denis Erkal

Stellar streams trace the gravitational potential of their host galaxies and offer a direct probe of dark matter halo geometry. Cosmological simulations predict that halo shapes depend on both baryonic physics and the nature of dark matter,…

Astrophysics of Galaxies · Physics 2026-05-11 Sirui Wu , Nathaniel Starkman , Sarah Pearson , Jacob Nibauer , Juan Miro-Carretero , David Martinez-Delgado

The positions and velocities of stellar streams have been used to constrain the mass and shape of the Milky Way's dark matter halo. Several extragalactic streams have already been detected, though it has remained unclear what can be…

Astrophysics of Galaxies · Physics 2023-09-21 Jacob Nibauer , Ana Bonaca , Kathryn V. Johnston

Cold or Warm, the Dark Matter substructure spectrum must extend to objects with masses as low as $10^7 M_\odot$, according to the most recent Lyman-$\alpha$ measurements. Around a Milky Way-like galaxy, more than a thousand of these…

Astrophysics of Galaxies · Physics 2015-10-28 Denis Erkal , Vasily Belokurov

Co-moving groups of stars (streams) are well known in the velocity space of the disc near the Sun. Many are thought to arise from resonances with the Galactic bar or spiral arms. In this work, we search for similar moving groups in the…

Astrophysics of Galaxies · Physics 2025-07-16 Adam M. Dillamore , Jason L. Sanders , Vasily Belokurov , Hanyuan Zhang

The GD-1 star stream is currently the best available for identifying density fluctuations, "gaps", along its length as a test of the LCDM prediction of large numbers of dark matter sub-halos orbiting in the halo. Density variations of some…

Astrophysics of Galaxies · Physics 2016-03-23 Raymond G. Carlberg

Dark matter sub-halos that pass near or through a thin tidal star stream locally increase its velocity dispersion. Subsequent orbital evolution further increases the velocity dispersion and stream width, lowering the surface density of a…

Astrophysics of Galaxies · Physics 2023-07-06 Raymond G. Carlberg , Hayley Agler

We study the formation of the Milky Way's halo in a $\Lambda$CDM cosmology by scaling down a high resolution simulation of the formation of a cluster of galaxies. We determine how much phase-space substructure is left over from the objects…

Astrophysics · Physics 2009-09-25 Amina Helmi , Simon D. M. White , Volker Springel

Recent years have seen the discovery of an ever growing number of stellar debris streams and clouds. These structures are typically detected as extended and often curvilinear overdensities of metal-poor stars that stand out from the…

Astrophysics of Galaxies · Physics 2016-04-06 Carl J. Grillmair , Jeffrey L. Carlin

Stellar streams from disrupted globular clusters are dynamically cold structures that are sensitive to perturbations from dark matter subhalos, allowing them in principle to trace the dark matter substructure in the Milky Way. We model,…

Astrophysics of Galaxies · Physics 2026-05-13 Duncan K. Adams , Aditya Parikh , Oren Slone , Rouven Essig , Manoj Kaplinghat , Adrian M. Price-Whelan

We use the very high resolution, fully cosmological simulations from the Aquarius project, coupled to a semi-analytical model of galaxy formation, to study the phase-space distribution of halo stars in "solar neighbourhood"-like volumes. We…

Astrophysics of Galaxies · Physics 2015-06-16 Facundo A. Gómez , Amina Helmi , Andrew P. Cooper , Carlos S. Frenk , Julio F. Navarro , Simon D. M. White

Tidal debris streams from galaxy satellites can provide insight into the dark matter distribution in halos. This is because we have more information about stars in a debris structure than about a purely random population of stars: we know…

Astrophysics of Galaxies · Physics 2016-03-30 Kathryn V. Johnston , Raymond G. Carlberg