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Related papers: Shape of the Galactic Orbits in Clusters

200 papers

We present a preliminary analysis of the effect of dynamical friction on the orbits of part of the globular clusters in our Galaxy. Our study considers an anisotropic velocity dispersion field approximated using the results of studies in…

(abridged) In this paper we derive observed and modelled shape parameters (apparent ellipticity and orientation of the ellipse) of 650 Galactic open clusters identified in the ASCC-2.5 catalogue. We provide the observed shape parameters of…

By using the ENACS data, we have studied the properties of emission-line galaxies (ELG) in clusters. The fraction of ELG in clusters is 16~%; this fraction is slightly dependent on the cluster velocity dispersion, being larger for…

Astrophysics · Physics 2007-05-23 A. Biviano , P. Katgert , A. Mazure , M. Moles , R. den Hartog , P. Focardi

Rotation curves are often used to estimate the mass distribution of spiral galaxies, assuming circular rotation of disks. However, non-circular motions caused by a non-axisymmetric gravitational potential, such as a stellar bar, may disturb…

Astrophysics · Physics 2009-11-07 Jin Koda , Keiichi Wada

The mass and anisotropy of an elliptical galaxy can be simultaneously determined from velocity dispersion and line profile shape measurements. We describe the principles, techniques, and limitations of this approach, and the results…

Astrophysics · Physics 2007-05-23 Ortwin Gerhard , Gunther Jeske , R. P. Saglia , Ralf Bender

We present an analysis of the spatial orientations of galaxies in the 247 optically selected rich Abell clusters, having in the considered area at least 100 members. We investigated the relation between angles giving information about…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Wlodzimierz Godlowski , Paulina Piwowarska , Elena Panko , Piotr Flin

We quantify the evolution of the spiral, S0 and elliptical fractions in galaxy clusters as a function of cluster velocity dispersion ($\sigma$) and X-ray luminosity ($L_X$) using a new database of 72 nearby clusters from the WIde-Field…

We estimate the distribution of intrinsic shapes of the APM galaxy clusters from their corresponding distribution of projected shapes. We smooth the discrete galaxy distribution and define the cluster shape by fitting the best ellipse to…

Astrophysics · Physics 2007-05-23 Spyros Basilakos , Manolis Plionis , Steve Maddox

We present the results of a study for galaxy orbits in galaxy clusters using a spectroscopic sample of galaxies in Sloan Digital Sky Survey (SDSS) and 2dF Galaxy Redshift Survey (2dFGRS). We have determined the member galaxies of Abell…

Astrophysics · Physics 2008-11-26 Ho Seong Hwang , Myung Gyoon Lee

We study the motion of stars in a star cluster which revolves in a circular orbit about its parent galaxy. The star cluster is modelled as an ellipsoid of uniform spatial density. We exhibit two 2-parameter families of self-consistent…

Astrophysics · Physics 2008-11-26 David G. M. Mitchell , Douglas C. Heggie

The intrinsic shape of galaxy clusters can be obtained through a combination of X-ray and Sunyaev-Zeldovich effect observations once cosmological parameters are assumed to be known. In this paper we discuss the feasibility of modelling…

Astrophysics · Physics 2009-11-11 M. Sereno , E. De Filippis , G. Longo , M. W. Bautz

Globular clusters are valuable fossil records of the formation and evolution of their host galaxies. The color distribution of elliptical galaxy globular cluster systems indicates an episodic formation history, consistent with a merger…

Astrophysics · Physics 2007-05-23 Stephen E. Zepf

We present a simple model for the shape of the distribution function of galaxy peculiar velocities. We show how both nonlinear and linear theory terms combine to produce a distribution which has an approximately Gaussian core with…

Astrophysics · Physics 2009-10-31 Ravi K. Sheth , Antonaldo Diaferio

The rotation velocity of the spiral pattern of the Galaxy is determined by direct observation of the birthplaces of open clusters of stars in the galactic disk as a function of their age. Our measurement does not depend on any specific…

Astrophysics · Physics 2009-11-10 W. S. Dias , J. R. D. Lépine

In light of recent findings from the kinematic morphology-density relation, we investigate whether the same trends exist in the original morphology density relation, using the same data as Dressler. In addition to Dressler's canonical…

Astrophysics of Galaxies · Physics 2015-05-20 R. C. W. Houghton

We investigate the internal dynamics of anisotropic, rotating globular clusters with a multimass stellar population by performing new direct N-body simulations. In addition to the well-known radial mass segregation effect, where heavy stars…

Astrophysics of Galaxies · Physics 2019-12-18 Ákos Szölgyén , Yohai Meiron , Bence Kocsis

Variations in the number of globular clusters per unit galaxy luminosity, which is the specific frequency, and the mass of globular clusters per unit total available mass, are reviewed. Correlations with galaxy luminosity and morphology,…

Astrophysics · Physics 2009-10-31 Bruce G. Elmegreen

We test the hypothesis that globular clusters form in supergiant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that such large, dense, and cold gas clouds assemble naturally in current hierarchical models…

Astrophysics · Physics 2010-07-27 Oleg Y. Gnedin , Jose L. Prieto

The stellar velocity fields of elliptical galaxies hold clues to their dynamical structure and origin. The construction of velocity field models is greatly simplified by assuming an approximate geometrical form for the streamlines of the…

Astrophysics · Physics 2009-10-30 R. F. Anderson , Thomas S. Statler

I review the field of globular cluster system (GCS) kinematics, including a brief primer on observational methods. The kinematical structures of spiral galaxy GCSs so far appear to be broadly similar. The inferred rotation and mass profiles…

Astrophysics · Physics 2007-05-23 Aaron J. Romanowsky