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Related papers: The faintest galaxies

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This paper introduces new phase-space models of dwarf spheroidal galaxies (dSphs). The stellar component has an isotropic, lowered isothermal (or King) distribution function. A physical basis for the isotropization of stellar velocities is…

Astrophysics of Galaxies · Physics 2015-05-19 N. C. Amorisco , N. W. Evans

Maximum disk mass models fitted to galaxy rotation curves are used to show that dark matter (DM) halos in late-type and dwarf spheroidal (dSph) galaxies satisfy well defined scaling laws. Halos in less luminous galaxies have smaller core…

Astrophysics · Physics 2007-05-23 John Kormendy , K. C. Freeman

In the last decade, we have been able to probe further down the galaxy luminosity function than ever before and expand into the regime of ultra-faint dwarfs (UFDs), which are some of the best probes we have of small-scale cosmology and…

The dwarf galaxy companions to the Milky Way are unique cosmological laboratories. With luminosities as low as 10^-7 L_MW, they inhabit the lowest mass dark matter halos known to host stars and are presently the most direct tracers of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Beth Willman

The recently discovered Ursa Major dwarf spheroidal (dSph) galaxy candidate is about five to eight times less luminous than the faintest previously known dSphs And IX, Draco, and UMi. In this Letter, we present velocity measurements of…

Astrophysics · Physics 2009-11-13 J. T. Kleyna , M. I. Wilkinson , N. W. Evans , G. Gilmore

We argue that, at least a fraction of the newly discovered population of ultra-faint dwarf spheroidal galaxies in the Local Group constitute the fossil relic of a once ubiquitous population of dwarf galaxies formed before reionization with…

Astrophysics · Physics 2011-02-11 Mia S. Bovill , Massimo Ricotti

Ultra-faint dwarf galaxies (UFDs) are newcomers among galaxies, and are the faintest galaxies in the observed universe. To date, they have only been found around the Milky Way Galaxy and M31 in the Local Group. We present the discovery of…

Astrophysics of Galaxies · Physics 2015-06-23 In Sung Jang , Myung Gyoon Lee

Low mass galaxies in the Local Group are dominated by dark matter and comprise the well studied ``dwarf Spheroidal" (dSph) class, with typical masses of $10^{9-10}M_\odot$ and also the equally numerous ``ultra faint dwarfs" (UFD),…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-20 Alvaro Pozo , Tom Broadhurst , George F. Smoot , Tzihong Chiueh , Hoang Nhan Luu , Mark Vogelsberger , Philip Mocz

Dwarf spheroidal galaxies are the smallest known stellar systems where under Newtonian interpretations, a significant amount of dark matter is required to explain observed kinematics. In fact, they are in this sense the most heavily dark…

Astrophysics of Galaxies · Physics 2016-08-31 X. Hernandez

Ultra-faint dwarf galaxies (UFDs) are promising observable proxies to building blocks of galaxies formed in the early Universe. We study the formation and evolution of UFDs using cosmological hydrodynamic simulations. In particular, we show…

Astrophysics of Galaxies · Physics 2021-06-23 Yuta Tarumi , Naoki Yoshida , Anna Frebel

We provide new constraints on the dark matter halo density profile of Milky Way (MW) dwarf spheroidal galaxies (dSphs) using the phase-space distribution function (DF) method. After assessing the systematics of the approach against mock…

Astrophysics of Galaxies · Physics 2024-05-31 Kevin E. Andrade , Manoj Kaplinghat , Mauro Valli

In recent years the Sloan Digital Sky Survey has unraveled a new population of ultra-faint dwarf galaxies (UFDs) in the vicinity of the Milky Way (MW) whose origin remains a puzzle. Using a suite of collisionless N-body simulations, we…

Astrophysics of Galaxies · Physics 2015-06-03 Ewa L. Lokas , Stelios Kazantzidis , Lucio Mayer

The scenario consistent with a wealth of observations for the missing mass problem is that of weakly interacting dark matter particles. However, arguments or proposals for a Newtonian or relativistic modified gravity scenario continue to be…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-21 Weikang Lin , Mustapha Ishak

We study a suite of extremely high-resolution cosmological FIRE simulations of dwarf galaxies ($M_{\rm halo} \lesssim 10^{10}$$M_{\odot}$), run to $z=0$ with $30 M_{\odot}$ resolution, sufficient (for the first time) to resolve the internal…

Motivated by the stellar fossil record of Local Group (LG) dwarf galaxies, we show that the star-forming ancestors of the faintest ultra-faint dwarf galaxies (UFDs; ${\rm M}_{\rm V}$ $\sim -2$ or ${\rm M}_{\star}$ $\sim 10^{2}$ at $z=0$)…

Astrophysics of Galaxies · Physics 2017-05-31 Daniel R. Weisz , Michael Boylan-Kolchin

Reproducing the physical characteristics of ultra-faint dwarf galaxies (UFDs) in cosmological simulations is challenging, particularly with respect to stellar metallicity and galaxy size. To investigate these difficulties in detail, we…

Ultra-faint dwarf (UFD) galaxies are a promising probe for dark matter (DM) physics as they are the most DM-dominated systems known. The Milky Way (MW) hosts many UFDs for which the properties of their DM distribution have been inferred…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-06 Moritz S. Fischer , Hai-Bo Yu

The discovery of Ultra-Faint Dwarf (UFD) galaxies in the halo of the Milky Way extends the faint end of the galaxy luminosity function to a few hundred solar luminosities. This extremely low luminosity regime poses a significant challenge…

Astrophysics of Galaxies · Physics 2015-05-30 R. R. Munoz , N. Padmanabhan , M. Geha

Ultra-faint dwarf galaxies (UFDs, $M_* < 10^5 M_\odot$) offer unique insights into early chemical evolution in low-mass systems. However, interpreting their metallicity distribution functions (MDFs) has been challenging due to limited…

The stellar initial mass function at high redshift is an important defining property of the first stellar systems to form and may also play a role in various dark matter problems. We here determine the faint stellar luminosity function in…