English
Related papers

Related papers: The velocity dispersion and mass function of the o…

200 papers

We use the distant outer halo globular cluster Palomar 14 as a test case for classical vs. modified Newtonian dynamics (MOND). Previous theoretical calculations have shown that the line-of-sight velocity dispersion predicted by these…

Astrophysics of Galaxies · Physics 2009-11-13 K. Jordi , E. K. Grebel , M. Hilker , H. Baumgardt , M. Frank , P. Kroupa , H. Haghi , P. Côté , S. G. Djorgovski

Precise radial velocity measurements from HIRES on the Keck I telescope are presented for 40 stars in the outer halo globular cluster NGC 2419. These data are used to probe the cluster's stellar mass function and search for the presence of…

Astrophysics of Galaxies · Physics 2015-05-13 H. Baumgardt , P. Cote , M. Hilker , M. Rejkuba , S. Mieske , S. G. Djorgovski , P. Stetson

We present an analysis of the radial dependence of the stellar mass function in the diffuse outer-halo globular cluster Palomar 14. Using archival HST/WFPC2 data of the cluster's central 39 pc (corresponding to ~0.85*r_h) we find that the…

Astrophysics of Galaxies · Physics 2013-01-23 Matthias J. Frank , Eva K. Grebel , Andreas H. W. Küpper

Palomar 4 is a low-density globular cluster with a current mass $\approx30000 M_{\odot}$ in the outer halo of the Milky Way with a two-body relaxation time of the order of a Hubble time. Yet, it is strongly mass segregated and contains a…

Astrophysics of Galaxies · Physics 2017-01-24 Akram Hasani Zonoozi , Hosein Haghi , Pavel Kroupa , Andreas H. W. Küpper , Holger Baumgardt

We present evidence for mass segregation in the outer-halo globular cluster Palomar 14, which is intuitively unexpected since its present-day two-body relaxation time significantly exceeds the Hubble time. Based on archival Hubble Space…

Astrophysics of Galaxies · Physics 2014-07-29 Matthias J. Frank , Eva K. Grebel , Andreas H. W. Kuepper

We have measured Keck/HIRES radial velocities for 30 candidate red giants in the direction of Palomar 13: an object traditionally cataloged as a compact, low-luminosity globular cluster. From a sample of 21 confirmed members, we find a…

Astrophysics · Physics 2009-11-07 Patrick Cote , S. G. Djorgovski , Georges Meylan , S. Castro , J. K. McCarthy

We investigate the velocity dispersion of Pal 14, an outer Milky-Way globular cluster at Galactocentric distance of 71 kpc with a very low stellar density (central density 0.1-0.2 Msun/pc^3). Due to this low stellar density the binary…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas H. W. Kuepper , Pavel Kroupa

We present Keck/DEIMOS spectroscopy and CFHT/MegaCam photometry for the Milky Way globular cluster Palomar 13. We triple the number of spectroscopically confirmed members, including many repeat velocity measurements. Palomar 13 is the only…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 J. D. Bradford , M. Geha , R. Munoz , F. A. Santana , J. D. Simon , P. Cote , P. B. Stetson , E. Kirby , S. G. Djorgovski

We use direct $N$-body calculations to study the evolution of the unusually extended outer halo globular cluster Palomar 4 (Pal~4) over its entire lifetime in order to reproduce its observed mass, half-light radius, velocity dispersion and…

Wide-field photometric data from the Sloan Digital Sky Survey have recently revealed that the Galactic globular cluster Palomar 5 is in the process of being tidally disrupted (Odenkirchen et al. 2001). Here we investigate the kinematics of…

Recently, combining radial velocities from Keck/HIRES echelle spectra with published proper motion membership probabilities, Cote et al (2002) observed a sample of 21 stars, probable members of Palomar 13, a globular cluster in the Galactic…

Astrophysics · Physics 2011-08-23 A. Blecha , G. Meylan , P. North , F. Royer

We determine the mean velocity dispersion of six Galactic outer halo globular clusters, AM 1, Eridanus, Pal 3, Pal 4, Pal 15, and Arp 2 in the weak acceleration regime to test classical vs. modified Newtonian dynamics (MOND). Owing to the…

Astrophysics of Galaxies · Physics 2015-05-27 Hosein Haghi , Holger Baumgardt , Pavel Kroupa

We investigate the mean velocity dispersion and the velocity dispersion profile of stellar systems in MOND, using the N-body code N-MODY, which is a particle-mesh based code with a numerical MOND potential solver developed by Ciotti,…

Astrophysics of Galaxies · Physics 2014-11-18 Hosein Haghi , Holger Baumgardt , Pavel Kroupa , Eva K. Grebel , Michael Hilker , Katrin Jordi

The proper motions of stars in the outskirts of globular clusters are used to estimate cluster velocity dispersion profiles as far as possible within their tidal radii. We use individual color-magnitude diagrams to select high probability…

Astrophysics of Galaxies · Physics 2021-12-08 Raymond G. Carlberg , Carl J. Grillmair

We have determined masses, stellar mass functions and structural parameters of 112 Milky Way globular clusters by fitting a large set of N-body simulations to their velocity dispersion and surface density profiles. The velocity dispersion…

Astrophysics of Galaxies · Physics 2018-07-03 H. Baumgardt , M. Hilker

An analysis of large-area CO J=3-2 maps from the James Clerk Maxwell Telescope for 12 nearby spiral galaxies reveals low velocity dispersions in the molecular component of the interstellar medium. The three lowest luminosity galaxies show a…

We report the determination of high-accuracy radial velocities for 299 members of the globular cluster M92 using the Hydra multi-object spectrograph on the WIYN telescope. We have concentrated on stars outside of the central region of the…

Astrophysics · Physics 2008-11-26 G. A. Drukier , H. N. Cohn , P. M. Lugger , S. D. Slavin , R. C. Berrington , B. W. Murphy

We present a new determination of the cluster mass function and velocity dispersion function in a volume $\sim10^7 h^3$Mpc$^{-3}$ using the Fourth Data Release of the Sloan Digital Sky Survey (SDSS). We use the caustic technique to remove…

Astrophysics · Physics 2008-11-26 Kenneth Rines , Antonaldo Diaferio , Priyamvada Natarajan

We recently published velocity measurements of luminous globular clusters in the galaxy NGC1052-DF2, concluding that it lies far off the canonical stellar mass - halo mass relation. Here we present a revised velocity for one of the globular…

We present a detailed kinematic analysis of the outer halo globular cluster (GC) system of M31. Our basis for this is a set of new spectroscopic observations for 78 clusters lying at projected distances between Rproj ~20-140 kpc from the…

‹ Prev 1 2 3 10 Next ›