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Related papers: Kinematic properties of the field elliptical NGC 7…

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Previous studies have shown that the kinematics of the field elliptical galaxy NGC 7507 do not necessarily require dark matter. This is troubling because, in the context of LCDM cosmologies, all galaxies should have a large dark matter…

Astrophysics of Galaxies · Physics 2015-06-23 Richard R. Lane , Ricardo Salinas , Tom Richtler

We present new Planetary Nebula Spectrograph observations of the ordinary elliptical galaxy NGC 4494, resulting in positions and velocities of 255 PNe out to 7 effective radii (25 kpc). We also present new wide-field surface photometry from…

As part of our current programme to test LCDM predictions for dark matter (DM) haloes using extended kinematical observations of early-type galaxies, we present a dynamical analysis of the bright elliptical galaxy NGC 4374 (M84) based on…

Recent results from the Planetary Nebula Spectrograph (PN.S) survey have revealed a rapidly falling velocity dispersion profile in the nearby elliptical galaxy NGC 3379, casting doubts on whether this intermediate-luminosity galaxy has the…

There exist isolated elliptical galaxies, whose dynamics can be modelled without resorting to dark matter or MOND, e.g. NGC 7507. The isolated elliptical NGC 5812 is another object to investigate a possible role of isolation. We use…

Astrophysics of Galaxies · Physics 2023-11-22 Tom Richtler , Ricardo Salinas , Richard Lane , Michael Hilker

We investigate the distribution of the luminous and the dark matter components in the isolated ellipticals NGC 7052 and NGC 7785, embedded in an emitting hot gas halo, by means of relevant X-ray and photometric data. In order to calculate…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Elisabetta Memola , Paolo Salucci , Ana Babic

We describe a non-parametric method for determining both the anisotropy and mass profiles of elliptical galaxies from velocity dispersions and velocity profile shapes along the line of sight. In this way, mass-to-light ratios out to 2-3…

Astrophysics · Physics 2007-05-23 Andi Kronawitter , Ortwin E. Gerhard , R. P. Saglia , Ralf Bender

We have obtained two-dimensional velocity fields of the dwarf spiral galaxy NGC 2976 in Halpha and CO. The high spatial (~75 pc) and spectral (13 km/s and 2 km/s, respectively) resolution of these observations, along with our multicolor…

Astrophysics · Physics 2009-11-10 Joshua D. Simon , Alberto D. Bolatto , Adam Leroy , Leo Blitz

We present HI observations of the elliptical galaxy NGC 2974, obtained with the Very Large Array. These observations reveal that the previously detected HI disc in this galaxy (Kim et al. 1988) is in fact a ring. By studying the harmonic…

(Abridged) We present an analysis of a Chandra ACIS-S observation of the elliptical galaxy NGC 720 to verify the existence of a dark matter (DM) halo and to measure its ellipticity. The ACIS-S3 image reveals over 60 point sources. For…

Astrophysics · Physics 2009-11-07 David A. Buote , Tesla E. Jeltema , Claude R. Canizares , Gordon P. Garmire

(abridged) We have measured line-of-sight velocity profiles (VPs) in the E0 galaxy NGC 6703 out to 2.6 R_e. From these data we constrain the mass distribution and the anisotropy of the stellar orbits in this galaxy. We have developed a…

Astrophysics · Physics 2015-06-24 Ortwin Gerhard , Gunther Jeske , R. P. Saglia , Ralf Bender

Elliptical galaxies are modelled as Sersic luminosity distributions with density profiles (DPs) for the total mass adopted from the DPs of haloes within dissipationless LambdaCDM N-body simulations. Ellipticals turn out to be inconsistent…

Astrophysics · Physics 2014-12-15 Gary A. Mamon , Ewa L. Lokas

We study the mass distribution in the late-type dwarf galaxy NGC 2976 through stellar kinematics obtained with the VIRUS-P integral-field spectrograph and anisotropic Jeans models as a test of cosmological simulations and baryonic processes…

New photometric and long-slit spectroscopic observations are presented for NGC 7113, PGC 1852, and PGC 67207 which are three bright galaxies residing in low-density environments. The surface-brightness distribution is analysed from the…

Astrophysics of Galaxies · Physics 2017-01-16 E. M. Corsini , G. A. Wegner , J. Thomas , R. P. Saglia , R. Bender

We construct a suite of discrete chemo-dynamical models of the giant elliptical galaxy NGC 5846. These models are a powerful tool to constrain both the mass distribution and internal dynamics of multiple tracer populations. We use Jeans…

We present new constraints on the density profiles of dark matter (DM) halos in seven nearby dwarf galaxies from measurements of their integrated stellar light and gas kinematics. The gas kinematics of low mass galaxies frequently suggest…

The thickness of the neutral hydrogen layer, coupled with the rotation curve, traces the outer dark matter potential. We estimate the amplitude of the flaring in spiral galaxies from a 3D model of the HI gas. Warps in particular are…

Astrophysics · Physics 2007-05-23 J. -F. Becquaert , F. Combes

We present line-of-sight stellar velocity distributions of elliptical galaxy NGC 821 obtained to approximately 100 arcsec (over 2 effective radii) with long-slit spectroscopy from the Hobby-Eberly Telescope. Our measured stellar…

Astrophysics · Physics 2011-01-20 Amy Forestell , Karl Gebhardt

We present the results of a study of weak lensing by galaxies based on 45.5 deg$^2$ of $R_C$ band imaging data from the Red-Sequence Cluster Survey (RCS). We present the first weak lensing detection of the flattening of galaxy dark matter…

Astrophysics · Physics 2008-11-26 Henk Hoekstra , Howard K. C. Yee , Michael D. Gladders

We estimated the dynamical surface mass density Sigma at the solar position between Z=1.5 and 4 kpc from the Galactic plane, as inferred from the kinematics of thick disk stars. The formulation is exact within the limit of validity of a few…

Astrophysics of Galaxies · Physics 2015-06-04 C. Moni Bidin , G. Carraro , R. A. Mendez , R. Smith
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