Search Publications
Probing small scale structure in the atmosphere of V471 Tauri
Walter, F. M.
The white dwarf in the eclipsing binary system V471 Tau is viewed through the atmosphere of the active K star prior to ingress and after egress. In the far UV the surface brightness of the hot white dwarf far outshines the K star emission. We can use this to probe the structure of the extended K star atmosphere along one line of sight, in absorpti…
Doppler Tomography of X-ray binaries
Boroson, B.; Vrtílek, S. D.; Quaintrell, H. +1 more
The Space Telescope Imaging Spectrograph (STIS) on HST provides the first ultraviolet data that are of sufficient spectral and temporal resolution to generate Doppler tomograms of X-ray binaries. We show both optical and ultraviolet maps constructed for the intermediate mass system Hercules X-1/HZ Her and the massive wind-fed system SMC X-1/SK160.…
Age-dating a star-burst with GEMINI/CIRPASS observations of the core of M83
Knapen, J. H.; Sharp, R. G.; Ryder, S. D. +2 more
We present preliminary results from a set of near-IR integral field spectroscopic observations of the central, star-burst, regions of the barred spiral galaxy M83, obtained with CIRPASS on Gemini-S. We present maps in the Paβ and [Fe{II}] ,1.257 µm emission lines which appear surprisingly different. We outline the procedure in which we will …
The central region of NGC 3077: ground-based photometry and age of bright `starlike' objects
Karachentsev, I. D.; Makarova, L. N.; Notni, P.
We present UBVI_C photometry of starlike objects in the central region of NGC 3077. The colour-colour and colour-magnitude diagrams of the objects are discussed. Many of the objects under consideration, starlike from the ground, are probably dense young star clusters (super star clusters, SSC). Ages spreading over ∼4 to ∼150 Myr are estimated for …
Stellar kinematics in the centers of globular clusters
Gerssen, J.
The high central stellar densities in globular clusters provide a unique environment to study the fundamental dynamical process of two-body relaxation. This process is the main driver of the dynamical evolution in the center of a globular cluster and has a profound effect on the structure of the cluster and on its stellar environment. We have obta…
HST/FOS Eclipse mapping of IP Pegasi in outburst
Horne, K.; Saito, R. K.; Baptista, R.
IP Pegasi is a deeply eclipsing dwarf nova (Porb= 3.8 hr) which shows 1-2 weeks-long, ≃ 2 mag outbursts every 60-120 days. During outbursts, tidally induced spiral shocks form in its accretion disc as the disc expands and its outer parts feel more effectively the gravitational attraction of the companion star (Steeghs, Harlaftis & H…