Search Publications
The vertical disc structure of U Geminorum in outburst
Naylor, T.; La Dous, C.
We have obtained phase-resolved UV spectroscopy from the International Ultraviolet Explorer, and V-band CCD photometry of U Gem in outburst. Our data show little or no orbital modulation outside eclipse, in contrast to the X-ray light curves during outburst, which show large dips. We find that a consistent model of the optical, UV and X-ray light …
A multiwavelength study of the starburst galaxy NGC7771
Alonso-Herrero, Almudena; Davies, Richard I.; Ward, Martin J.
We present a multiwavelength study of the interacting starburst galaxy NGC7771, including new optical and ultraviolet spectra and a previously unpublished soft X-ray ROSAT image and spectrum. The far-infrared, radio and X-ray fluxes suggest that a massive burst of star formation is currently in progress, but the small equivalent width of the Balme…
Redshifts of galaxies close to bright QSO lines of sight
Bowen, David V.; Blades, J. Chris; Osmer, Samantha J. +1 more
To expand the known number of low-redshift galaxies lying close to bright (V<17.2) QSO lines of sight, we have identified 24 galaxies within 11 arcmin of nine QSOs which have been observed with the Hubble Space Telescope (HST). Galaxies are found between redshifts of 0.0114 and 0.145 and lie between 39 and 749h^-1kpc from QSO sightlines. Knowin…
The chemical composition and binarity of beta Crateris
Stickland, D. J.; Kellett, B. J.; Smalley, B. +1 more
A detailed abundance analysis of the bright A-type star betaCrt is presented. It is found that most of the abundances are essentially solar, indicating that the star is not a hot Am star. The only prominent anomalies are an underabundance of Al and overabundances of S, Sr and Ba. The barium overabundance is the most prominent and has important imp…
Spin and beat phenomena in time-resolved Hubble Space Telescope UV spectroscopy of PQ GEM
Watson, M. G.; Mason, K. O.; Howell, S. B. +2 more
Results of the first low-resolution (6 Angstroms), time-resolved Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) observation of the prototypical strong-field intermediate polar system, PQ Gem, are presented. The lambdalambda1150-2600 continuum light curve is dominated by the 13.9-min rotational signature of the white dwarf at all UV w…
Comments on the amplification bias in lens statistics
Hamana, Takashi; Futamase, Toshifumi; Futamase, Kayoko +1 more
Amplification bias selection effects play an important role in lens statistics. We carefully examine the effect of amplification bias on lens statistics taking the following points into account. First, because each lens model has its own amplification bias, it must be estimated self-consistently. Secondly, in general, because the bias depends not …
A survey of vacuum-ultraviolet extinction curves based on International Ultraviolet Explorer spectra
Patriarchi, P.; Megier, A.; Aiello, S. +1 more
This paper presents the interstellar extinction curves derived from the International Ultraviolet Explorer (IUE) spectra with the aid of the already published `artificial standards'. The variety of possible shapes of the curves, demonstrated earlier on spectra from the TD/1 satellite, is fully confirmed.
HST observations of IP Pegasi in quiescence: the pre-eclipse spectrum
Eracleous, Michael; Szkody, Paula; Horne, Keith +5 more
We present time-resolved HST ultraviolet (UV) spectroscopy and ground-based optical photometry of the dwarf nova IP Pegasi in a quiescent state. The observations were obtained prior to an eclipse, when the bright spot caused by the impact of the accretion stream with the edge of the disc dominates the light output. The optical light curve is fairl…