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Related papers: Counting Dark Sub-halos with Star Stream Gaps

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The steepness of the central density profiles of dark matter (DM) in low-mass galaxy halos (e.g. dwarf galaxies) is a powerful probe of the nature of DM. We propose a novel scheme to probe the inner profiles of galaxy subhalos using stellar…

Astrophysics of Galaxies · Physics 2020-12-17 Khyati Malhan , Monica Valluri , Katherine Freese

The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models. Too small to host galaxies themselves, these subhaloes may still be detected…

We use a cosmological simulation of the Local Group to make quantitative and speculative predictions for direct detection experiments. Cold dark matter (CDM) halos form via a complex series of mergers, accretion events and violent…

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

The free-streaming length of dark matter depends on fundamental dark matter physics, and determines the abundance and concentration of dark matter halos on sub-galactic scales. Using the image positions and flux ratios from eight…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Daniel Gilman , Simon Birrer , Anna Nierenberg , Tommaso Treu , Xiaolong Du , Andrew Benson

Mysterious dark matter constitutes about 85% of all mass in the Universe. Clustering of dark matter plays the dominant role in the formation of all observed structures on scales from a fraction to a few hundreds of Mega-parsecs. Galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Nesar S. Ramachandra , Sergei F. Shandarin

The cold dark matter scenario predicts that a large number of dark subhalos should be located within the halo of each Milky-way sized galaxy. One tell-tale signature of such dark subhalos could be additional milliarcsecond-scale image…

Astrophysics · Physics 2009-11-13 E. Zackrisson , T. Riehm , O. Moeller , K. Wiik , P. Nurmi

The Pan Andromeda Archeological Survey (PAndAS) CFHT Megaprime survey of the M31-M33 system has found a star stream which extends about 120 kpc NW from the center of M31. The great length of the stream, and the likelihood that it does not…

The central density profiles in dwarf galaxy halos depend strongly on the nature of dark matter. Recently, in Malhan et al. (2021), we employed N-body simulations to show that the cuspy cold dark matter (CDM) subhalos predicted by…

Astrophysics of Galaxies · Physics 2023-01-04 Khyati Malhan , Monica Valluri , Katherine Freese , Rodrigo A. Ibata

We provide new constraints on the connection between galaxies in the local universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the $\Lambda$CDM model using WMAP7…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-20 Rachel M. Reddick , Risa H. Wechsler , Jeremy L. Tinker , Peter S. Behroozi

We study the amount and distribution of dark matter substructures within dark matter haloes, using a large set of high-resolution simulations ranging from group size to cluster size haloes, and carried our within a cosmological model…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 E. Contini , G. De Lucia , S. Borgani

To place the highly substructured stellar halos of the Milky Way and M31 in a larger context of hierarchical galaxy formation, it is necessary to understand the prevalence and properties of tidal substructure around external galaxies. This…

Astrophysics of Galaxies · Physics 2016-03-23 Jeffrey L. Carlin , Rachael L. Beaton , David Martinez-Delgado , R. Jay Gabany

Standard LCDM predicts that the major merger rate of galaxy-size dark matter halos rises rapidly with redshift. The average number of close companions per galaxy, Nc, is often used to infer the galaxy merger rate, however, recent…

We obtain predictions for the properties of cold dark matter annihilation radiation using high resolution hydrodynamic zoom-in cosmological simulations of Milky Way-like galaxies (APOSTLE project) carried out as part of the "Evolution and…

The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter 'halos' provide the scaffolding for all luminous…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-26 James E. Taylor

Stellar streams are sensitive tracers of low-mass dark matter subhalos and provide a means to test the Cold Dark Matter (CDM) paradigm on small scales. In this work, we connect the intrinsic velocity dispersion of the GD-1 stream to the…

Astrophysics of Galaxies · Physics 2025-10-03 Jacob Nibauer , Ana Bonaca , Adrian M. Price-Whelan , David N. Spergel , Jenny E. Greene

Measurements of velocity and density perturbations along stellar streams in the Milky Way provide a time integrated measure of dark matter substructure at larger galactic radius than the complementary instantaneous inner halo strong lensing…

Astrophysics of Galaxies · Physics 2016-10-26 Raymond Carlberg , Carl Grillmair

Several long, dynamically cold stellar streams have been observed around the Milky Way Galaxy, presumably formed from the tidal disruption of globular clusters. In integrable potentials---where all orbits are regular---tidal debris…

The free streaming length of dark matter particles determines the abundance of structure on sub-galactic scales. We present a statistical technique, amendable to any parameterization of subhalo density profile and mass function, to probe…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 Daniel Gilman , Simon Birrer , Tommaso Treu , Charles R. Keeton , Anna Nierenberg

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