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Related papers: Testing modified gravity with dwarf spheroidal gal…

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We perform a test of John Moffat's Modified Gravity theory (MOG) within the Milky Way, adopting the well known "Rotation Curve" method. We use the dynamics of observed tracers within the disk to determine the gravitational potential as a…

Astrophysics of Galaxies · Physics 2018-12-10 Carolina Negrelli , Maria Benito , Susana Landau , Fabio Iocco , Lucila Kraiselburd

A number of mechanisms have been proposed to connect star-forming dwarf irregular galaxies with the formation of non-star-forming dwarf spheroidal galaxies, but distinguishing between these mechanisms has been difficult. We use the Via…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Colin T. Slater , Eric F. Bell

Modifications to GR generically predict time and scale-dependent effects which may be probed by observations of strong lensing by galaxies. Measurements of the stellar velocity dispersion determine the dynamical mass whereas measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-14 Tristan L. Smith

Making use of public spectra from Cimatti et al (2008), we measure for the first time the velocity dispersion of spheroid-like massive (M_star ~ 10^11 M_sun) galaxies at z ~ 1.6. By comparing with galaxies of similar stellar mass at lower…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. Javier Cenarro , Ignacio Trujillo

We introduce a method for measuring the slopes of mass profiles within dwarf spheroidal (dSph) galaxies directly from stellar spectroscopic data and without adopting a dark matter halo model. Our method combines two recent results: 1)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Matthew G. Walker , Jorge Peñarrubia

The observed stellar kinematics of dispersion-supported galaxies are often used to measure dynamical masses. Recently, several analytical relationships between the stellar line-of-sight velocity dispersion, the projected (2D) or deprojected…

The Galactic dwarf spheroidal galaxies (dSphs) provide valuable insight into dark matter (DM) properties and its role in galaxy formation. Their close proximity enables the measurement of line-of-sight velocities for resolved stars, which…

As an alternative to dark matter models, MOdified Gravity (MOG) theory can compensate for dark matter by a covariant modification of Einstein gravity. The theory introduces two additional scalar fields and one vector field. The aim is to…

Astrophysics of Galaxies · Physics 2015-06-16 J. W. Moffat , S. Rahvar

We predict the metallicity distribution of stars and the age-metallicity relation for 6 Dwarf Spheroidal (dSph) galaxies of the Local Group by means of a chemical evolution model which is able to reproduce several observed abundance ratios…

Astrophysics · Physics 2009-11-10 Gustavo A. Lanfranchi , Francesca Matteucci

The equation of motion in the generally covariant modified gravity (MOG) theory leads for weak gravitational fields and the non-relativistic limit to a modification of the Newtonian gravitational acceleration law, expressed in terms of two…

Astrophysics of Galaxies · Physics 2016-10-31 J. W. Moffat

Dwarf satellite galaxies of the Milky Way appear to be gravitationally bound, but their stars' orbital motion seems too fast to allow this given their visible mass. This is akin to the larger-scale galaxy rotation problem. In this paper, a…

General Physics · Physics 2017-03-06 M. E. McCulloch

Alternative gravitations of Milgrom (MOND), Moffat (MOG), and CDM scenarios all simulate rotation curves of spirals with reasonable details. They display significant disparities however in predicting the stellar mass-to-light ($M_*/L$)…

Astrophysics of Galaxies · Physics 2015-05-19 Akram Hasani Zonoozi , Hosein Haghi

We study galaxy evolution from z=1 to z=0 as a function of velocity dispersion sigma for galaxies with sigma > 95 km/s based on the measured and Monte Carlo realised local velocity dispersion functions (VDFs) of galaxies and the revised…

Astrophysics · Physics 2015-05-13 Kyu-Hyun Chae

This article explores the agreement between the predictions of Modified Newtonian Dynamics (MOND) and the rotation curves and stellar velocity dispersion profiles measured by the DiskMass Survey. A bulge-disk decomposition was made for each…

We analyzed 10 dwarf spheroidal galaxies (dSphs) in the Local Group, and found two distinct sequences on the $M_{\rm vir} / L$ -- $M_{\rm vir}$ plane: $M_{\rm vir} / L \propto M_{\rm vir}^{1.6}$ for $M_{\rm vir} < 10^8 M_\odot$ whereas…

Astrophysics · Physics 2007-05-23 Tsutomu T. Takeuchi , Hiroyuki Hirashita

We use a specific form of the interpolation function in the MOND formalism, which optimally accounts for the internal structure of dwarf spheroidal (dSph) galaxies, to explore the consequences it has on the scaling relations seen in these…

Astrophysics of Galaxies · Physics 2010-03-04 X. Hernandez , S. Mendoza , T. Suarez , T. Bernal

Precise measurements of mass in dark matter dominated dwarf spheroidal galaxies are of great importance for testing the theories of structure formation. We use $N$-body simulations of the tidal evolution of a dwarf galaxy orbiting the Milky…

Astrophysics of Galaxies · Physics 2014-08-25 Klaudia Kowalczyk , Ewa L. Lokas

We derive the distribution of the phantom dark matter in the eight classical dwarf galaxies surrounding the Milky Way, under the assumption that modified Newtonian dynamics (MOND) is the correct theory of gravity. According to their…

Astrophysics of Galaxies · Physics 2020-10-02 Alistair O. Hodson , Antonaldo Diaferio , Luisa Ostorero

We propose a cosmological scenario for the formation and evolution of dwarf spheroidal galaxies (dSphs), satellites of the Milky Way (MW). An improved version of the semi-analytical code GAMETE (GAlaxy Merger Tree & Evolution) is used to…

Astrophysics · Physics 2009-11-13 S. Salvadori , A. Ferrara , R. Schneider

Mass models of 15 nearby dwarf and spiral galaxies are presented. The galaxies are selected to be homogeneous in terms of the method used to determine their distances, the sampling of their rotation curves (RCs) and the mass-to-light ratio…

Astrophysics of Galaxies · Physics 2015-06-18 Toky Randriamampandry , Claude Carignan