Search Publications
Evolution of X-ray emission from young massive star clusters
Oskinova, L. M.
The evolution of X-ray emission from young massive star clusters is modelled, taking into account the emission from the stars as well as from the cluster wind. It is shown that the level and character of the soft (0.2-10 keV) X-ray emission change drastically with cluster age and are tightly linked with stellar evolution. Using the modern X-ray ob…
The evolution of the galaxy B-band rest-frame morphology to z~ 2: new clues from the K20/GOODS sample
Cimatti, A.; Daddi, E.; Rodighiero, G. +7 more
We present a detailed analysis of the evolution of the rest-frame B-band morphology of K-selected galaxies with 0 < z < 2.5. This work is based on the K20 spectroscopic sample (Ks < 20) located within the Chandra Deep Field South area, coupled with the public deep GOODS (Great Observatories Origins Deep Surveys) Hubble Space Telescope (HS…
Dynamical modelling of stars and gas in NGC 2974: determination of mass-to-light ratio, inclination and orbital structure using the Schwarzschild method
Krajnović, Davor; Emsellem, Eric; Cappellari, Michele +2 more
We study the large-scale stellar and gaseous kinematics of the E4 galaxy NGC 2974, based on panoramic integral-field data obtained with SAURON. We quantify the velocity maps with Fourier methods (kinemetry), and show that the large-scale kinematics is largely consistent with axisymmetry. We construct general axisymmetric dynamical models for the s…
Cosmological weak lensing with the HST GEMS survey
Bell, Eric F.; Wisotzki, Lutz; Wolf, Christian +16 more
We present our cosmic shear analysis of GEMS, one of the largest wide-field surveys ever undertaken by the Hubble Space Telescope. Imaged with the Advanced Camera for Surveys (ACS), GEMS spans 795 arcmin2 in the Chandra Deep Field South. We detect weak lensing by large-scale structure in high-resolution F606W GEMS data from ~60 resolved…
New constraints on modified Newtonian dynamics from galaxy clusters
Silk, Joseph; Pointecouteau, Etienne
We revisit the application of modified Newtonian dynamics (MOND) to galaxy clusters. We confront the high-quality X-ray data for eight clusters of galaxies observed by the XMM-Newton satellite with the predictions of MOND. We obtain a ratio of the MOND dynamical mass to the baryonic mass of Mm/Mb= 4.94 +/- 0.50 in the outer p…
Physics of accretion in the millisecond pulsar XTE J1751-305
Gierliński, Marek; Poutanen, Juri
We have undertaken an extensive study of X-ray data from the accreting millisecond pulsar XTE J1751-305 observed by RXTE and XMM-Newton during its 2002 outburst. In all aspects this source is similar to the prototypical millisecond pulsar SAX J1808.4-3658, except for the higher peak luminosity of 13 per cent of Eddington, and the optical depth of …
Density-potential pairs for spherical stellar systems with Sérsic light profiles and (optional) power-law cores
Graham, Alister W.; Terzić, Balša
Popular models for describing the luminosity-density profiles of dynamically hot stellar systems (e.g. Jaffe, Hernquist, Dehnen) were constructed with the desire to match the deprojected form of an R1/4 light profile. Real galaxies, however, are now known to have a range of different light-profile shapes that scale with mass. Consequent…
Ly-α and ultraviolet emission from high-redshift gamma-ray burst hosts: to what extent do gamma-ray bursts trace star formation?
Östlin, G.; Jóhannesson, G.; Watson, D. +9 more
We report the result of a search for Lyα emission from the host galaxies of the gamma-ray bursts (GRBs) 030226 (z= 1.986), 021004 (z= 2.335) and 020124 (z= 3.198). We find that the host galaxy of GRB 021004 is an extended (around 8 kpc) strong Lyα emitter with a rest-frame equivalent width (EW) of 68+12-11Å, and a star format…
The nature of the molecular gas system in the core of NGC 1275
Edge, A. C.; Johnstone, R. M.; Wilman, R. J.
We present near-infrared integral field spectroscopy of the central kiloparsec of NGC 1275 at the heart of the Perseus cluster of galaxies, obtained with the Integral Field Unit (IFU) of the United Kingdom Infrared Telescope (UKIRT) Imaging Spectrometer (UIST). The nuclear ro-vibrational H2 emission is spatially resolved and is likely t…
A submillimetre survey of Lyman α haloes in the SA22 protocluster at z= 3.1
Ivison, R. J.; Taniguchi, Y.; Smail, Ian +7 more
We present the results from a submillimetre (submm) survey of a sample of 23 giant Lyman α (Lyα) emitting nebulae in the overdensity at z= 3.09 in the SA22 field. These objects, which have become known as Lyα Blobs (LABs), have a diverse range of morphology and surface brightness, but the nature of their power source remains unclear, with both coo…