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相关论文: Galaxy mass distributions for some extreme orbital…

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The measured rotation velocity profiles of mature spiral galaxies are successfully described with a gravitational model consisting of a thin axisymmetric disk of finte radius. The disk is assumed uniformly thin but with variable radial mass…

天体物理学 · 物理学 2008-03-06 James Q. Feng , C. F. Gallo

Given the dimensions (including thickness) and rotation speeds for an axisymmetric galaxy, a closed-loop iterative method is designed to find the total mass, density, and surface-mass density (SMD)distributions. There is no need for…

天体物理学 · 物理学 2016-08-30 Kenneth F. Nicholson

The Hypervelocity Star survey presents the currently largest sample of radial velocity measurements of halo stars out to 80 kpc. We apply spherical Jeans modeling to these data in order to derive the mass profile of the Galaxy. We restrict…

星系天体物理 · 物理学 2010-08-31 Oleg Y. Gnedin , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

Given the dimensions (including thickness) of a galaxy, and its rotation profile, a method is shown that finds the mass and density distributions in the defined envelope that will cause that rotation profile with near-exact speed matches.…

天体物理学 · 物理学 2007-05-23 Kenneth F. Nicholson

We model a spiral galaxy by a thin axially symmetric disk that includes both visible and dark matter. The surface mass density of the disk is calculated directly from the rotational velocity curve without extra assumptions. We simplify the…

天体物理学 · 物理学 2007-05-23 Valentin Kostov

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…

天体物理学 · 物理学 2009-11-07 Jin Koda , Keiichi Wada

A unified parametrization of the circular velocity, which accurately fits 850 galaxy rotation curves without needing in advance the knowledge of the luminous matter components, nor a fixed dark matter halo model, is proposed. A notable…

星系天体物理 · 物理学 2018-03-14 E. Lopez Fune

The accuracy and robustness of a simple method to estimate the total mass profile of a galaxy is tested using a sample of 65 cosmological zoom-simulations of individual galaxies. The method only requires information on the optical surface…

宇宙学与河外天体物理 · 物理学 2015-06-04 N. Lyskova , E. Churazov , I. Zhuravleva , T. Naab , L. Oser , O. Gerhard , X. Wu

A powerful method to measure the mass profile of a galaxy is through the velocities of tracer particles distributed through its halo. Transforming this kind of data accurately to a mass profile M(r), however, is not a trivial problem. In…

星系天体物理 · 物理学 2016-05-03 Gwendolyn M. Eadie , William E. Harris , Lawrence M. Widrow

In this work, two new axisymmetric models for the Galactic mass distribution are presented. Motivated by recent results, these two models include the contribution of a stellar thin disc and of a thick disc, as massive as the thin…

星系天体物理 · 物理学 2017-02-01 Ektoras Pouliasis , Paola Di Matteo , Misha Haywood

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…

天体物理学 · 物理学 2007-05-23 Andi Kronawitter , Ortwin E. Gerhard , R. P. Saglia , Ralf Bender

We estimate the mass of the central black hole in our Galaxy from stellar kinematical data published by Ghez et al. (1998) and Genzel et al. (2000). For this we develop a method, related to Merritt (1993), for non-parametrically…

天体物理学 · 物理学 2009-11-06 Dalia Chakrabarty , Prasenjit Saha

We develop a novel way of finding total mass density profiles in Sersic ellipticals, to about 3 times the major axis effective radius, using no other information other than what is typically available for distant galaxies, namely the…

天体物理仪器与方法 · 物理学 2015-05-13 Dalia Chakrabarty , Brendan Jackson

An efficient method is developed which allows the calculation of distributions of the surface density in the equilibrium disk configurations with an isolated point mass at the center corresponding to known distributions of the angular…

天体物理学 · 物理学 2009-11-07 N. R. Sibgatullin , A. Garcia , V. S. Manko

Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large…

天体物理学 · 物理学 2009-10-30 A. M. Ghez , B. L. Klein , M. Morris , E. E. Becklin

Determining the dynamical mass profiles of dispersion-supported galaxies is particularly challenging due to projection effects and the unknown shape of their velocity anisotropy profile. Our goal is to develop a machine learning algorithm…

The stellar density profile a galaxy is typically summarised with two numbers: total stellar mass and half-light radius. The total mass of a galaxy, however, is not a well-defined quantity, due to the finite depth of photometric…

星系天体物理 · 物理学 2020-09-23 Alessandro Sonnenfeld

We collected radial velocities of more than 50.000 individual stars in 156 Galactic globular clusters (GGC) and matched them with HST photometry and Gaia DR2 proper motions. This allowed us to derive the GGC's mean proper motions and space…

星系天体物理 · 物理学 2020-03-18 Michael Hilker , Holger Baumgardt , Antonio Sollima , Andrea Bellini

Given the dimensions(including thickness) of an axisymmetric galaxy, Newton's law is used in integral form to find the density distributions required to match a wide range of orbital speed profiles. Newton's law is not modified and no…

天体物理学 · 物理学 2007-05-23 Kenneth F. Nicholson

This paper describes how the non-gravitational contribution to Galactic Velocity Rotation Curves can be explained in terms of a negative Cosmological Constant ($\Lambda$). It will be shown that the Cosmological Constant leads to a velocity…

天体物理学 · 物理学 2007-05-23 S. B. Whitehouse , G. V. Kraniotis
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