Related papers: The massive elliptical galaxy NGC 4649 from the pe…
We create dynamical models of the massive elliptical galaxy, NGC 4649, using the N-body made-to-measure code, NMAGIC, and kinematic constraints from long-slit and planetary nebula (PN) data. We explore a range of potentials based on…
We present the first dynamical study of the globular cluster system of NGC 4636. This giant elliptical galaxy is claimed to be extremely dark matter dominated, according to X-ray observations. Using the VLT with FORS2/MXU, we obtained…
From observations with the GMOS multi-slit spectrograph on the Gemini North telescope, we have obtained spectra for 39 globular cluster candidates in the Virgo giant elliptical galaxy NGC 4649 (M60), of which 38 are confirmed globular…
The renormalization group framework can be applied to Quantum Field Theory on curved space-time, but there is no proof whether the beta-function of the gravitational coupling indeed goes to zero in the far infrared or not. In a recent paper…
We compare optical and high quality x-ray data for three bright ellipticals in the Virgo cluster, NGC 4472, 4649, and 4636. The distribution of total mass in NGC 4472 and 4649 determined from x-ray data is sensitive to the stellar mass over…
We determine the total enclosed mass profile from 0.7 to 35 kpc in the elliptical galaxy NGC 4636 based on the hot interstellar medium temperature profile measured using the Chandra X-ray Observatory, and other X-ray and optical data. The…
Context: Regarding the significant interest in both dark matter and the application of MOND to early-type galaxies, we investigate the MOND theory by comparing its predictions, for models of constant mass-to-light ratio, with observational…
Using a slitless spectroscopy method with (a) the 8.2 m Subaru telescope and its FOCAS Cassegrain spectrograph, and (b) the ESO Very Large Telescope (VLT) unit 1 (Antu) and its FORS2 Cassegrain spectrograph, we have detected 326 planetary…
We determine the total enclosed mass profile from 0.7 to 35 kpc in the elliptical galaxy NGC 4636 based on the hot interstellar medium temperature profile measured using the Chandra X-ray Observatory, and other X-ray and optical data. The…
We present a kinematic analysis of the globular cluster(GC) system in the giant elliptical galaxy (gE) NGC 4636 in the Virgo cluster. Using the photometric and spectroscopic database of 238 GCs, we have investigated the kinematics of the GC…
We present new radial velocities for 289 globular clusters around NGC 4636, the southernmost giant elliptical galaxy of the Virgo cluster. The data were obtained with FORS2/MXU at the Very Large Telescope. Together with data analysed in an…
We present new Planetary Nebula Spectrograph observations of the ordinary elliptical galaxy NGC 4494, resulting in positions and velocities of 255 PNe out to 7 effective radii (25 kpc). We also present new wide-field surface photometry from…
There exist isolated elliptical galaxies, whose dynamics can be modelled without resorting to dark matter or MOND, e.g. NGC 7507. The isolated elliptical NGC 5812 is another object to investigate a possible role of isolation. We use…
ASCA observations of NGC 4636 and a southern region have revealed extended X-ray emission to a radius of about 300 kpc from the galaxy. The symmetric nature of the observed surface brightness around NGC 4636 indicates its association to…
NGC 4649 (M60) is one of a handful of giant Virgo ellipticals. We have obtained Gemini/GMOS spectra for 38 GCs associated with this galaxy. Applying the multi-index chi^2 minimisation technique of Proctor & Sansom (2002) with the single…
We present a spectroscopic study of the globular clusters (GCs) in the giant elliptical galaxy NGC 4636 in the Virgo cluster. We selected target GC candidates using the Washington photometry derived from the deep CCD images taken at the…
We investigate the unusually rich cluster system of NGC4636 with wide-field Washington photometry. The globular cluster luminosity function can be followed roughly 1 mag beyond the turn-over magnitude. This corresponds to a distance modulus…
We present new wide-field photometry and spectroscopy of the globular clusters (GCs) around NGC 4649 (M60), the third brightest galaxy in the Virgo cluster. Imaging of NGC 4649 was assembled from a recently-obtained HST/ACS mosaic, and new…
We present analysis of a Chandra observation of the elliptical galaxy NGC 4555. The galaxy lies in a very low density environment, either isolated from all galaxies of similar mass or on the outskirts of a group. Despite this, NGC 4555 has…
We present new radial velocities for 87 globular clusters around the elliptical galaxy NGC 4472, and combine these with our previously published data to create a data set of velocities for 144 globular clusters around NGC 4472. We utilize…