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Related papers: Discrete dynamical modelling of omega Centauri

200 papers

We use more than a decade of radial velocity measurements for $\alpha$ Cen A, B, and Proxima Centauri from HARPS, CHIRON, and UVES to identify the $M \sin i$ and orbital periods of planets that could have been detected if they existed. At…

Earth and Planetary Astrophysics · Physics 2017-12-27 Lily L. Zhao , Debra A. Fischer , John M. Brewer , Matt Giguere , Bárbara Rojas-Ayala

Omega Centauri ($\omega$ Cen) is one of the most complex star clusters in the Milky Way, and likely the stripped nucleus of an accreted dwarf galaxy. Being the subject of debate between it hosting an intermediate-mass black hole (IMBH) or a…

Astrophysics of Galaxies · Physics 2025-03-26 S. Saracino , S. Kamann , F. Wragg , S. Dreizler , K. Kremer , M. Latour , J. Müller-Horn , N. Neumayer , A. C. Seth , G. van de Ven , M. Häberle

We present a new geometrical method which uses weak gravitational lensing effects in clusters to constrain the cosmological parameters Omega and Lambda. On each background galaxy, a cluster induces a convergence and a shear terms, which…

Astrophysics · Physics 2007-05-23 L. Gautret , B. Fort , Y. Mellier

The aim of this paper is to study the efficiency of different approaches to interloper treatment in dynamical modelling of galaxy clusters. Using cosmological N-body simulation of standard LCDM model, we select 10 massive dark matter haloes…

We present a theoretical model which aims at predicting the clustering properties of X-ray clusters in flux-limited surveys for different cosmological scenarios. The model uses the theoretical and empirical relations between mass,…

Time-delay distance measurements from strongly lensed quasars provide a robust, independent method for determining the Hubble constant ($H_0$). This approach cross-checks $H_0$ estimates from the distance ladder in the late universe and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-18 Han Wang , Sherry H. Suyu , Aymeric Galan , Aleksi Halkola , Michele Cappellari , Anowar J. Shajib , Miha Cernetic

We have analyzed the kinematics of OB stars from the list by Xiang et al. (2021) that contains $\sim$13 000 single OB stars. For these stars there are photometric distance estimates and proper motions from the Gaia catalogue and…

Astrophysics of Galaxies · Physics 2022-07-06 V. V. Bobylev , A. T. Bajkova , G. M. Karelin

We report the discovery of a double-lined, spectroscopic, eclipsing binary in the Orion star-forming region. We analyze the system spectroscopically and photometrically to empirically determine precise, distance-independent masses, radii,…

We estimate the mass of the Milky Way (MW) within 21.1 kpc using the kinematics of halo globular clusters (GCs) determined by Gaia. The second Gaia data release (DR2) contained a catalogue of absolute proper motions (PMs) for a set of…

Astrophysics of Galaxies · Physics 2019-03-20 Laura L. Watkins , Roeland P. van der Marel , Sangmo Tony Sohn , N. Wyn Evans

(abridged) We estimate the cluster-galaxy cross-correlation function (Xi_cg), from the APM galaxy and galaxy cluster surveys, both in real space from the inversion of projected statistics and in redshift space using the galaxy and cluster…

Astrophysics · Physics 2009-10-30 Rupert Croft , Gavin Dalton , George Efstathiou

The Halo Assembly in Lambda-CDM: Observations in 7 Dimensions (HALO7D) dataset consists of Keck II/DEIMOS spectroscopy and Hubble Space Telescope-measured proper motions of Milky Way (MW) halo main sequence turnoff stars in the CANDELS…

We quantify the expected observed statistical and systematic uncertainties of the escape velocity as a measure of the gravitational potential and total mass of galaxy clusters. We focus our attention on low redshift (z < 0.15) clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Daniel Gifford , Christopher J. Miller , Nicholas Kern

The Fourier decomposition was applied to the light curves of the short period variable stars discovered by the OGLE team in Omega Cen. The phi_21 parameters are confined in a narrow strip for periods between 0.042 d and 0.07 d. Toward…

Astrophysics · Physics 2007-05-23 Ennio Poretti

The morphology of galaxy clusters reflects the epoch at which they formed and hence depends on the value of the mean cosmological density, Omega. Recent studies have shown that the distribution of dark matter in clusters can be mapped from…

Astrophysics · Physics 2015-06-24 Gillian Wilson , Shaun Cole , Carlos S. Frenk

We present stellar specific angular momentum $j_*$ measurements of two $z\sim 1.5$ galaxies in the KGES sample and 12 DYNAMO $z\sim 0.1$ analogues of high-redshift galaxies. We combine natural seeing integral field spectroscopic data to…

For many classes of astronomical and astrophysical binary systems, long observational records of their radial velocity $V$, which is their directly observable quantity, are available. For exoplanets close to their parent stars, they cover…

General Relativity and Quantum Cosmology · Physics 2022-08-26 Lorenzo Iorio , Matteo Luca Ruggiero

We herein determine the average integrated mass loss from stars stars belonging to the dominant metal-poor population ([Fe/H] ~ --1.7) of the Galactic globular cluster omega Centauri (NGC 5139) during their red giant and horizontal branch…

Solar and Stellar Astrophysics · Physics 2015-05-28 Iain McDonald , Christian I. Johnson , Albert A. Zijlstra

Context. Omega Cen is the largest known globular cluster in the Milky Way. It is also quite a complex object with a large metallicity spread and multiple stellar populations. Despite a number of studies over the past several decades, the…

Astrophysics of Galaxies · Physics 2025-04-23 Nagaraj Vernekar , Sara Lucatello , Pete Kuzma , Lorenzo Spina

We introduce a new methodology to robustly determine the mass profile, as well as the overall distribution, of Local Group satellite galaxies. Specifically we employ a statistical multilevel modelling technique, Bayesian hierarchical…

Astrophysics of Galaxies · Physics 2015-06-23 Gregory D. Martinez

We report the results of an extensive VLT high-resolution imaging campaign of the central region of the giant globular cluster omega Centauri. More than 100,000 stars have been measured in the inner 9'x 9' region of the cluster. On the…

Astrophysics · Physics 2011-07-18 A. Sollima , F. R. Ferraro , E. Pancino , M. Bellazzini