We incorporate a contribution to reionization from X-rays within analytic and semi-numerical simulations of the 21-cm signal arising from neutral hydrogen during the epoch of reionization. The relatively long X-ray mean free path (MFP) means that ionizations due to X-rays are not subject to the same density bias as UV ionizations, resulting in a substantive modification to the statistics of the...

Implicit surfaces obtained by convolution of multi-dimensional primitives with some potential function, are a generalisation of popular implicit surface models: blobs, metaballs and soft objects. These models di er in their choice of potential functions but agree upon the use of underlying modelling primitives, namely, points. In this paper a method is described for modelling and rendering impl...

Chandra or XMM-Newton observations of quiescent low–mass X–ray binaries can provide important constraints on the equation of state of neutron stars. The mass and radius of the neutron star can potentially be determined from fitting a neutron star atmosphere model to the observed X–ray spectrum. For a radius measurement it is of critical importance that the distance to the source is well constra...

Assuming a naive star formation history, we construct the synthetic X-ray source populations for comparison with the X-ray luminosity function (XLF) of the interacting galaxies NGC 4038/4039 using a population synthesis code. We have considered highand intermediate-mass X-ray binaries, young rotation-powered pulsars and fallback disc-fed black holes in modelling the bright X-ray sources detecte...

This paper concerns a new sub-field of computer graphics, namely volume graphics, which aims to develop voxel-based modelling and rendering techniques for general purpose graphics in addition to its original playing field, volume visualisation. Building upon our recent work on the modelling of graphics scenes composed of multiple volumetric datasets, we present three different algorithms for re...

Multi-frequency (X-ray, optical and radio) observations of galaxy clusters indicate that the atmospheres of these cosmic structures consist of a complex structure of thermal (hot and warm) and non-thermal (with different origin and spectra) distribution of electrons (and protons) which is, therefore, far from its modelling as a single, thermal electronic gas. This evidence requires to go beyond...