Hintze Centre for Astrophysical Surveys

Research group

Research theme

Sub department

About

The fundamental properties of early-type galaxies in the Coma Cluster

ASTROPHYSICS AND SPACE SCIENCE 277 (2001) 429-432

Authors:

SAW Moore, JR Lucey, H Kuntschner, RL Davies, M Colless
More details from the publisher

The peculiar motions of early-type galaxies in two distant regions - VI. The maximum-likelihood Gaussian algorithm

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 324:2 (2001) 389-419

Authors:

RP Saglia, M Colless, D Burstein, RL Davies, RK McMahan, G Wegner
More details from the publisher

The peculiar motions of early-type galaxies in two distant regions - VII. Peculiar velocities and bulk motions

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 321:2 (2001) 277-305

Authors:

M Colless, RP Saglia, D Burstein, RL Davies, RK Jr McMahan, G Wegner
More details from the publisher

VLBA Observations of the Superluminal Radio Jet from Cygnus X-1 in the Low/Hard X-Ray State

Chapter in Microquasars, Springer Nature (2001) 121-122

Authors:

Chris De La Force, Ralph Spencer, A Stirling, M Garrett, R Fender
More details from the publisher

Coupling of the X-ray and radio emission in the black hole candidate and compact jet source GX 339-4

Astronomy and Astrophysics 359:1 (2000) 251-268

Authors:

S Corbel, RP Fender, AK Tzioumis, M Nowak, V McIntyre, P Durouchoux, R Sood

Abstract:

We report the results of a long-term campaign of radio, soft- and hard- X-ray observations of the galactic black hole candidate GX 339-4. In the Low-Hard X-ray state the system displays a strong 3-way linear correlation between soft-and hard-X-rays and radio emission, implying a coupling between the Comptonising corona and a radio-emitting compact jet. In this state the radio emission is linearly polarised at a level of around 2%, with an almost constant polarisation angle, indicative of a favored axis in this system probably related to the compact jet and/or black hole spin axis. In the Off X-ray state the radio emission declines with the X-ray emission to below detectable levels, suggesting that it is simply a lower-luminosity version of the Low-Hard state. In the High-Soft state both the hard-X-ray and radio emission are suppressed. We also note that the transitions from the Low-Hard state to the High-Soft state (and the reverse) are possibly associated with discrete ejection(s) of expanding relativistic plasma.