English
Related papers

Related papers: Deep HST Imaging in 47 Tucanae: A Global Dynamical…

200 papers

This is the second of three papers that search for the predicted stellar cusp around the Milky Way's central black hole, Sagittarius A*, with new data and methods. We aim to infer the distribution of the faintest stellar population…

Astrophysics of Galaxies · Physics 2017-12-27 R. Schödel , E. Gallego-Cano , H. Dong , F. Nogueras-Lara , A. T. Gallego-Calvente , P. Amaro-Seoane , H. Baumgardt

The properties of globular cluster systems (GCSs) in the core of the nearby galaxy clusters Fornax and Hydra I are presented. In the Fornax cluster we have gathered the largest radial velocity sample of a GCS system so far, which enables us…

Astrophysics of Galaxies · Physics 2015-12-24 Michael Hilker , Tom Richtler

As part of a radial velocity survey of low Galactic latitude structures that we undertook with the 2dF spectrograph on the AAT, we present the radial velocities of more than 1500 Red Giant Branch and Red Clump stars towards the centre of…

Astrophysics · Physics 2009-11-10 N. F. Martin , R. A. Ibata , B. C. Conn , G. F. Lewis , M. Bellazzini , M. J. Irwin

Context. Open clusters are very good tracers of the evolution of the Galactic disc. Thanks to Gaia, their kinematics can be investigated with an unprecedented precision and accuracy. Aims. The distribution of open clusters in the 6D phase…

Internal rotation is considered to play a major role in determining the structure and dynamics of some globular clusters. We present a dynamical analysis of the photometry and three-dimensional kinematics of 47 Tuc and omega Cen, by means…

Astrophysics of Galaxies · Physics 2013-02-05 Paolo Bianchini , Anna Lisa Varri , Giuseppe Bertin , Alice Zocchi

We establish an extragalactic, zero-motion frame of reference within the deepest optical image of a globular star cluster, an HST 123-orbit exposure of M4 (GO 8679, cycle 9). The line of sight beyond M4 (l,b (deg) = 351,16) intersects the…

The study of the kinematics of globular clusters (GCs) offers the possibility of unveiling their long term evolution and uncovering their yet unknown formation mechanism. Gaia DR2 has strongly revitalized this field and enabled the…

Astrophysics of Galaxies · Physics 2020-03-18 P. Bianchini

Aims. We present the first three-dimensional internal motions for individual stars in the Draco dwarf spheroidal galaxy. Methods. By combining first-epoch $Hubble$ $Space$ $Telescope$ observations and second-epoch $Gaia$ Data Release 2…

Astrophysics of Galaxies · Physics 2020-01-08 Davide Massari , Amina Helmi , Alessio Mucciarelli , Laura V. Sales , Lorenzo Spina , Eline Tolstoy

Aims: We present the first measurement of the proper motion and orbit of the very distant and intriguing globular cluster NCG 2419. Methods: We have combined data from HST and Gaia DR1 to derive the relative proper motions of stars in the…

Astrophysics of Galaxies · Physics 2017-02-22 Davide Massari , Lorenzo Posti , Amina Helmi , Giuliana Fiorentino , Eline Tolstoy

We use stellar proper motions (PM) from Gaia Data Release 2 for studying the internal kinematics of Milky Way globular clusters. In addition to statistical measurement errors, there are significant spatially correlated systematic errors,…

Astrophysics of Galaxies · Physics 2019-08-07 Eugene Vasiliev

This paper presents the detailed results obtained in the search of density- velocity inhomogeneities in a volume limited and absolute magnitude limited sample of A-F type dwarfs within 125 parsecs of the Sun. A 3-D wavelet analysis is used…

Astrophysics · Physics 2009-10-30 E. Chereul , M. Crézé , O. Bienaymé

We present central velocity dispersions, masses, mass to light ratios ($M/L$s), and rotation strengths for 25 Galactic globular clusters. We derive radial velocities of 1951 stars in 12 globular clusters from single order spectra taken with…

Astrophysics of Galaxies · Physics 2015-06-23 Brian Kimmig , Anil Seth , Inese I. Ivans , Jay Strader , Nelson Caldwell , Tim Anderton , Dylan Gregersen

We present new B, V and I-band photometry for a sample of 43 local subdwarfs with HIPPARCOS parallax errors < 13%, in the metallicity range -1.0 < [Fe/H] < -0.3, which we use to perform main sequence (MS) fitting to the Galactic globular…

Astrophysics · Physics 2009-11-07 Susan M. Percival , Maurizio Salaris , Francois van Wyk , David Kilkenny

The stellar dynamics of Omega Centauri are inferred from the radial velocities of 469 stars measured with CORAVEL (Mayor et al. 1997). Rather than fit the data to a family of models, we generate estimates of all dynamical functions…

Astrophysics · Physics 2009-10-28 David Merritt , G. Meylan , M. Mayor

Isolated Local Group (LG) dwarf galaxies have evolved most or all of their life unaffected by interactions with the large LG spirals and therefore offer the opportunity to learn about the intrinsic characteristics of this class of objects.…

Astrophysics of Galaxies · Physics 2020-04-01 S. Taibi , G. Battaglia , M. Rejkuba , R. Leaman , N. Kacharov , G. Iorio , P. Jablonka , M. Zoccali

We present Hubble Space Telescope observations of the upper part (T_eff> 10 000 K) of the white dwarf cooling sequence in the globular cluster 47 Tucanae and measure a luminosity function of hot white dwarfs. Comparison with previous…

Solar and Stellar Astrophysics · Physics 2015-08-26 Bradley Hansen , Harvey Richer , Jason Kalirai , Ryan Goldsbury , Shane Frewen , Jeremy Heyl

We present an analysis of Galactic bulge stars from Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) observations of the Stanek window (l,b=[0.25,-2.15]) from two epochs approximately two years apart. This dataset is adjacent to the…

Solar and Stellar Astrophysics · Physics 2020-02-12 Sean K. Terry , Richard K. Barry , David P. Bennett , Aparna Bhattacharya , Jay Anderson , Matthew T. Penny

It is generally accepted today that Galactic globular clusters (GGCs) consist of at least two generations of stars that are different in their chemical composition and perhaps age. However, knowledge about the kinematical properties of…

Solar and Stellar Astrophysics · Physics 2014-09-05 A. Kucinskas , V. Dobrovolskas , P. Bonifacio

We present a spectroscopic analysis of HST/STIS and FOS low- and intermediate-resolution spectroscopy of 55 stars (turn-off stars, horizontal branch stars and blue stragglers) in four globular clusters (47 Tucanae, M3, NGC6752, and…

Stars in globular clusters formed and evolved in the most extreme environment: high density and low metallicity. If the formation of stars and planets are at all sensitive to environmental conditions, this should therefore be evident in…

Solar and Stellar Astrophysics · Physics 2021-11-24 Andrew J. Winter , Giovanni P. Rosotti , Cathie Clarke , Mirek Giersz
‹ Prev 1 8 9 10 Next ›