scholarly journals Three-dimensional structure of the Sagittarius dwarf spheroidal core from RR Lyrae

2020 ◽  
Vol 495 (4) ◽  
pp. 4124-4134 ◽  
Author(s):  
Peter S Ferguson ◽  
Louis E Strigari
Keyword(s):  
Dark Matter ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Major Axis ◽  
Prolate Spheroid ◽  
Dimensional Structure ◽  
Galactic Centre ◽  
Matter Distribution ◽  
Rr Lyrae ◽  
Dark Matter Distribution

ABSTRACT We obtain distances to a sample of RR Lyrae in the central core of the Sagittarius dwarf spheroidal galaxy from OGLE data. We use these distances, along with RR Lyrae from Gaia DR2, to measure the shape of the stellar distribution within the central ∼2 kpc. The best-fitting stellar distribution is triaxial, with axis ratios 1 : 0.76 : 0.43. A prolate-spheroid model is ruled out at high statistical significance relative to the triaxial model. The major axis is aligned nearly parallel to the sky plane as seen by an Earth-based observer and is nearly perpendicular to the direction of the Galactic Centre. This result may be compared to cosmological simulations which generally predict that the major axis of the dark matter distribution of subhalos is aligned with the Galactic Centre. The triaxial structure that we obtain can provide important constraints on the Sagittarius progenitor, as well as the central dark matter distribution under the assumption of dynamical equilibrium.

scholarly journals Evolution of the dark matter distribution with three-dimensional weak lensing

2005 ◽  
Vol 363 (3) ◽  
pp. 723-733 ◽  
Author(s):  
D. J. Bacon ◽  
A. N. Taylor ◽  
M. L. Brown ◽  
M. E. Gray ◽  
C. Wolf ◽  
...  
Keyword(s):  
Dark Matter ◽  
Three Dimensional ◽  
Weak Lensing ◽  
Matter Distribution ◽  
Dark Matter Distribution

scholarly journals DARK MATTER DYNAMICS AND INDIRECT DETECTION

2005 ◽  
Vol 20 (14) ◽  
pp. 1021-1036 ◽  
Author(s):  
GIANFRANCO BERTONE ◽  
DAVID MERRITT
Keyword(s):  
Dark Matter ◽  
Total Mass ◽  
Galactic Center ◽  
Direct Detection ◽  
Indirect Detection ◽  
Matter Distribution ◽  
Dark Matter Distribution ◽  
Particle Dark Matter ◽  
The Universe ◽  
Rule Out

Non-baryonic, or "dark", matter is believed to be a major component of the total mass budget of the Universe. We review the candidates for particle dark matter and discuss the prospects for direct detection (via interaction of dark matter particles with laboratory detectors) and indirect detection (via observations of the products of dark matter self-annihilations), focusing in particular on the Galactic center, which is among the most promising targets for indirect detection studies. The gravitational potential at the Galactic center is dominated by stars and by the supermassive black hole, and the dark matter distribution is expected to evolve on sub-parsec scales due to interaction with these components. We discuss the dominant interaction mechanisms and show how they can be used to rule out certain extreme models for the dark matter distribution, thus increasing the information that can be gleaned from indirect detection searches.

scholarly journals Dark matter distribution induced by a cosmic string wake in the nonlinear regime

2018 ◽  
Vol 98 (8) ◽  
Author(s):  
Disrael Camargo Neves da Cunha ◽  
Joachim Harnois-Deraps ◽  
Robert Brandenberger ◽  
Adam Amara ◽  
Alexandre Refregier
Keyword(s):  
Dark Matter ◽  
Cosmic String ◽  
Nonlinear Regime ◽  
Matter Distribution ◽  
Dark Matter Distribution

scholarly journals The Dark Matter Distribution in the Central Regions of Galaxy Clusters: Implications for Cold Dark Matter

2004 ◽  
Vol 604 (1) ◽  
pp. 88-107 ◽  
Author(s):  
David J. Sand ◽  
Tommaso Treu ◽  
Graham P. Smith ◽  
Richard S. Ellis
Keyword(s):  
Dark Matter ◽  
Galaxy Clusters ◽  
Cold Dark Matter ◽  
Matter Distribution ◽  
Central Regions ◽  
Dark Matter Distribution

scholarly journals Analysis of the very inner Milky Way dark matter distribution and gamma-ray signals

2016 ◽  
Vol 94 (12) ◽  
Author(s):  
V. Gammaldi ◽  
V. Avila-Reese ◽  
O. Valenzuela ◽  
A. X. Gonzalez-Morales
Keyword(s):  
Dark Matter ◽  
Milky Way ◽  
Gamma Ray ◽  
Matter Distribution ◽  
Dark Matter Distribution

Dark matter distribution in superthin galaxies

2020 ◽  
Vol 495 (4) ◽  
pp. 3722-3726
Author(s):  
Ilia Kalashnikov
Keyword(s):  
Dark Matter ◽  
Surface Density ◽  
Distribution Density ◽  
Spherically Symmetric ◽  
Matter Distribution ◽  
Galactic Disc ◽  
Density Profiles ◽  
Visible Matter ◽  
Simple Physical Model ◽  
Dark Matter Distribution

ABSTRACT This paper presents a new method of calculating dark matter density profiles for superthin axial symmetric galaxies without a bulge. This method is based on a simple physical model, which includes an infinitely thin galactic disc immersed in a spherically symmetric halo of dark matter. To obtain the desired distribution density, it suffices to know a distribution of visible matter surface density in a galaxy and a dependence of angular velocity on the radius. As a byproduct, the well-known expression, which reproduces surface density of a superthin galaxy expressed through a rotation law, was obtained.

scholarly journals OGLE-ing the Magellanic System: Three-Dimensional Structure

2018 ◽  
Vol 14 (S344) ◽  
pp. 86-89
Author(s):  
Anna M. Jacyszyn-Dobrzeniecka ◽  
Keyword(s):  
Three Dimensional ◽  
Neutral Hydrogen ◽  
Variable Stars ◽  
Dimensional Structure ◽  
Rr Lyrae Stars ◽  
Three Dimensional Structure ◽  
Rr Lyrae ◽  
Classical Cepheids ◽  
Lyrae Stars ◽  
Magellanic System

AbstractWe present a three-dimensional structure of the Magellanic System using over 9 000 Classical Cepheids and almost 23 000 RR Lyrae stars from the OGLE Collection of Variable Stars. Given the vast coverage of the OGLE-IV data and very high completeness of the sample, we were able to study the Magellanic System in great details.We very carefully studied the distribution of both types of pulsators in the Magellanic Bridge area. We show that there is no evident physical connection between the Clouds in RR Lyrae stars distribution. We only see the two extended structures overlapping. There are few classical Cepheids in the Magellanic Bridge area that seem to form a genuine connection between the Clouds. Their on-sky locations match very well young stars and neutral hydrogen density contours. We also present three-dimensional distribution of classical pulsators in both Magellanic Clouds.

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