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Related papers: Discrete dynamical modelling of omega Centauri

200 papers

We investigate the anisotropy of the stellar velocity dispersions within the effective radius, $R_{\rm e}$, in 24 ATLAS$^{\rm 3D}$ pure-bulge galaxies, 16 of which are kinematic slow rotators (SRs). We allow the spherical anisotropy…

Astrophysics of Galaxies · Physics 2019-04-03 Kyu-Hyun Chae , Mariangela Bernardi , Ravi K. Sheth

Photometry and kinematics of the giant elliptical galaxy NGC~5128 (Centaurus~A) based on planetary nebulae observations (Hui~\etal 1995) are used to build dynamical models which allow us to infer the presence of a dark matter halo. To this…

Astrophysics · Physics 2007-05-23 A. Mathieu , H. Dejonghe , X. Hui

We explore the possibility of detecting and characterizing the warp of the stellar disc of our Galaxy using synthetic Gaia data. The availability of proper motions and, for the brightest stars radial velocities, adds a new dimension to this…

Astrophysics of Galaxies · Physics 2015-06-19 H. Abedi , C. Mateu , L. A. Aguilar , F. Figueras , M. Romero-Gomez

We measure the line-of-sight accelerations of 26 binary pulsars due to the Milky Way's gravitational potential, and produce a 3-dimensional map of the acceleration field of the Galaxy. Acceleration measurements directly give us the change…

Astrophysics of Galaxies · Physics 2024-05-22 Thomas Donlon , Sukanya Chakrabarti , Lawrence M. Widrow , Michael T. Lam , Philip Chang , Alice C. Quillen

We present a method for fitting orbit-superposition models to the kinematics of discrete stellar systems when the available stellar sample has been filtered by a known selection function. The fitting method can be applied to any model in…

Astrophysics of Galaxies · Physics 2019-01-23 John Magorrian

We investigate the stellar and dynamical mass profiles in the centres of 25 brightest cluster galaxies (BCGs) at redshifts of 0.05 $\leq z \leq$ 0.30. Our spectroscopy enables us to robustly measure the Gauss-Hermite higher order velocity…

Astrophysics of Galaxies · Physics 2020-06-17 S. I. Loubser , A. Babul , H. Hoekstra , Y. M. Bahé , E. O'Sullivan , M. Donahue

NGC 5139 ($\omega$ Cen), is the closest candidate of a Nuclear Star Cluster that has been stripped of its host galaxy in the Milky Way. Despite extensive studies through the last decades, many open questions about the cluster remain,…

Astrophysics of Galaxies · Physics 2024-11-11 F. Wragg , S. Kamann , S. Saracino , M. Latour , S. Dreizler , S. Martens , A. Seth , D. Vaz , G. van de Ven

The structural and dynamical properties of star clusters are generally derived by means of the comparison between steady-state analytic models and the available observables. With the aim of studying the biases of this approach, we fitted…

Solar and Stellar Astrophysics · Physics 2015-05-12 A. Sollima , H. Baumgardt , A. Zocchi , E. Balbinot , M. Gieles , V. Henault-Brunet , A. L. Varri

We present a new empirical model for galaxy rotation curves that introduces a velocity correction term {\omega}, derived from observed stellar motion and anchored to Keplerian baselines. Unlike parametric halo models or modified gravity…

Astrophysics of Galaxies · Physics 2026-01-05 David C. Flynn , Jim Cannaliato

We construct a simple dynamical model of the massive globular cluster Omega Cen. The model includes simple treatments of dynamical evolution in a galactic tide, and evolution of single stars. Binary stars and rotation are neglected. The…

Astrophysics · Physics 2009-11-07 Mirek Giersz , Douglas C. Heggie

One of the biggest challenges in cosmology, the Hubble Tension, requires independent measurements of $H_0$, and strong lensing with time-delay cosmography is a promising avenue. The inclusion of spatially resolved kinematic data helps break…

Astrophysics of Galaxies · Physics 2026-02-10 Vishal Verma , Quinn Minor

We propose a method for measuring the cosmological density parameter $\Omega$ from the statistics of the divergence field, $\theta \equiv H^{-1} \div v$, the divergence of peculiar velocity, expressed in units of the Hubble constant, $H…

Astrophysics · Physics 2015-06-24 F. Bernardeau , R. Juszkiewicz , A. Dekel , F. R. bouchet

We analyze the velocity anisotropy of stars in real and energy space for a sample of Milky Way-like galaxies in the TNG50 simulation. We employ different selection criteria, including spatial, kinematic and metallicity cuts, and make three…

We compare dynamical mass estimates based on spatially extended stellar and ionized gas kinematics ($\mathrm{M_{dyn,*}}$ and $\mathrm{M_{dyn,eml}}$, respectively) of 157 star forming galaxies at $0.6\leq z<1$. Compared to $z\sim0$, these…

We present a variable star catalog of an extensive ground-based wide-field variability survey in the globular cluster omega Centauri. Using the ANU 40-inch (1m) telescope at Siding Spring Observatory, the cluster was observed with a 52'x52'…

Astrophysics · Physics 2008-11-26 David T. F Weldrake , Penny D Sackett , Terry J Bridges

We present a new discrete chemo-dynamical axisymmetric modeling technique, which we apply to the dwarf spheroidal galaxy Sculptor. The major improvement over previous Jeans models is that realistic chemical distributions are included…

Astrophysics of Galaxies · Physics 2016-09-07 Ling Zhu , Glenn van de Ven , Laura L. Watkins , Lorenzo Posti

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

We use masses, radii, and luminosities of the detached eclipsing binary OGLEGC17 derived from photometric and spectroscopic observations to calculate the age and distance of the globular cluster omega Cen. Age versus turnoff mass and age…

The motions of galaxies can be used to constrain the cosmological density parameter Omega and the clustering amplitude of matter on large scales. The mean relative velocity of galaxy pairs, estimated from the Mark III survey, indicates that…

Astrophysics · Physics 2009-10-31 R. Juszkiewicz , P. G. Ferreira , H. A. Feldman , A. H. Jaffe , M. Davis

The peripheral regions of globular clusters (GCs) are extremely challenging to study due to their low surface brightness nature and the dominance of Milky Way contaminant populations along their sightlines. We have developed a probabilistic…

Astrophysics of Galaxies · Physics 2021-08-18 Pete B. Kuzma , Annette M. N. Ferguson , Jorge Peñarrubia