Search Publications
Infrared mapping of the dust disc around VEGA
Walker, H. J.; Klaas, U.; Heinrichsen, I.
ISOPHOT has been used to perform high-resolution 60-µm scans of Vega, and these have been compared with those from gammaDra, to obtain a Gaussian width of 22+/-2 arcsec. The dust disc around Vega has been mapped, resolving it at 60 and 90 µm with ISOPHOT. At 90 µm a Gaussian width of 36+/-3 arsec has been derived. In addition, mu…
A multiwavelength study of the early evolution of the classical nova LMC 1988 1
Sonneborn, G.; Baron, E.; Hauschildt, Peter H. +3 more
LMC 1988 1 was a moderately fast, CO, dust-forming classical nova. It was observed extensively in many different wavelength regions during its early evolution. The UV, optical and infrared light curves of LMC 1988 1 are very similar to those of the Galactic Nova V1668 Cyg 1978. As in V1668 Cyg, LMC 1988 1 showed the presence of an optically thin d…
Spectral analysis of the high-gravity extreme helium star LSIV+6 deg2
Jeffery, C. S.
The optical spectrum of the early B hydrogen-deficient star LSIV+6 deg2 has been analysed. With T_eff=31000K, logg=4.05, n_H~10^-4 and n_c~0.1 (relative abundances by number), it is the hottest high-gravity extreme helium star (EHe) yet studied. The Hei spectrum shows all predicted permitted and forbidden transitions in absorption. LSIV+6 deg2 is …
Late-type dwarf galaxies in the Virgo cluster - I. The samples
Brosch, Noah; Almoznino, Elchanan
We selected samples of late-type dwarf galaxies in the Virgo cluster with HI information. The galaxies were observed at the Wise Observatory using several broad-band and Hα bandpasses. UV measurements were carried out with the IUE Observatory from VILSPA, and with the FAUST shuttle-borne UV telescope. We describe the observations in detail, paying…
Planetary nebulae with ISO: A58 and A78 - nebulae with hydrogen-poor ejecta
Kimeswenger, S.; Kerber, F.; Weinberger, R.
We present ISO observations of A58 and A78. Both objects are suspected to have undergone late He flashes (`born-again' nebulae). With ISOCAM we have been able to obtain data of much higher spatial resolution over the wavelength range 4.5-18 µm than has been possible in the past. In order to extract full information from our data we have deve…
Confirmation of previous ground-based Cepheid P-L zero-points using HIPPARCOS trigonometric parallaxes
Sandage, Allan; Tammann, G. A.
Comparisons show agreement at the 0.1-mag level between the calibration of the Cepheid period-luminosity (P-L) relation by Feast & Catchpole (FC) using the early release of Hipparcos data and four previous ground-based calibrations, three of which are either largely or totally independent of the distance to the Large Magellanic Cloud (LMC). Ea…
The physical parameters of the evolving population of faint galaxies
Ellis, Richard; Glazebrook, Karl; Abraham, Roberto +2 more
The excess number of blue galaxies at faint magnitudes is a subject of much controversy. Recent Hubble Space Telescope results have revealed a plethora of galaxies with peculiar morphologies tentatively identified as the evolving population. We report the results of optical spectroscopy and near-infrared photometry of a sample of faint HST galaxie…
The ultraviolet spectrum of the narrow-line Seyfert 1 galaxy RE J1034+396
Siemiginowska, A.; Mason, K. O.; Puchnarewicz, E. M.
RE J1034+396 has one of the hottest big blue bumps of any Seyfert 1 (kT_BB~120 eV) and thus provides a valuable insight into the physics in the nuclei of active galaxies. In this paper, we present UV spectroscopy of RE J1034+396, taken with the Faint Object Spectrograph on the Hubble Space Telescope. With a spectral resolution of ~1-2 Angstroms FW…
A radio-jet-galaxy interaction in 3C 441
Rawlings, Steve; Lacy, Mark; Ridgway, Susan E. +1 more
Multiwavelength imaging and spectroscopy of the z=0.708 radio galaxy 3C 441 and a red aligned optical/infrared component are used to show that the most striking aspect of the radio-optical `alignment effect' in this object is due to the interaction of the radio jet with a companion galaxy in the same group or cluster. The stellar population of the…
Modelling the 10-image lensed system B1933+503
Nair, S.
A gravitational lens model is presented for the newly discovered 10-image system B1933+503. The underlying object, revealed by modelling, is a triple radio source on the scale of a couple of hundred mas that is well-aligned along the line of sight with a foreground and somewhat flattened lensing galaxy, the orientation and location of which match …