Search Publications
The starburst galaxy NGC 6090: from 2.5µm to 200µm.
Schulz, B.; Laureijs, R. J.; Abraham, P. +10 more
We have carried out broad band photometry of the interacting galaxy system NGC 6090 from 3.6 to 200µm using ISOPHOT. This is complemented by a low resolution spectrum in the wavelength range 2.5-11.5µm. The IR spectral energy distribution of a starburst galaxy is shown with unprecedented detail. From our Far Infrared measurements we ca…
Multifrequency monitoring of RU Lupi. II. The model.
Rossi, C.; Giovannelli, F.; Vittone, A. A. +4 more
The data obtained during multifrequency monitoring of extreme T Tauri star RU Lupi and presented in Giovannelli et al. (1995), are explained by a model in which a young star with a moderately strong global magnetic field is actively accreting mass from a circumstellar disk. We argue that the magnetic field pressure stops the accretion disk at the …
The chemical compositions of three main-sequence B-type stars in the Large Magellanic Cloud.
Howarth, I. D.; Dufton, P. L.; Brown, P. J. F. +1 more
High-resolution observations of three B-type main-sequence stars in the Large Magellanic Cloud (LMC) have been obtained with the UCL echelle spectrograph on the 3.9-m Anglo-Australian Telescope. These spectra and IUE low-resolution spectroscopic data have been analysed using LTE model-atmosphere techniques, to derive stellar atmospheric parameters…
Eclipses in the symbiotic system CH CYG
Bode, M. F.; Skopal, A.; Lloyd, H. M. +1 more
In this Letter we describe observational evidence of eclipses which strongly suggest that CH Cyg is a triple system with a very high inclination. We present U and V photoelectric photometry, along with optical and ultraviolet low- and high-resolution spectroscopy taken around the inferior spectroscopic conjunctions of the red giant in the symbioti…
High resolution spectroscopy of symbiotic stars. II. RW Hydrae: orbit, eclipses, and stellar parameters.
Schmutz, W.; Schild, H.; Muerset, U.
With IUE spectra and published optical photometry, we show that the symbiotic star RW Hya is an eclipsing binary. We use a series of high resolution optical spectra to determine the orbital elements and basic parameters of the stellar components in the system. We measure the orbital velocity amplitude of the red star and determine the binary mass …
Elemental abundances in normal late-B and HgMn stars from co-added IUE spectra. IV. Gallium.
Smith, K. C.
An analysis is presented of the ultraviolet gallium resonance lines in International Ultraviolet Explorer (IUE) spectra of 40 normal, superficially normal, and HgMn-type late-B stars. Gallium abundances are derived by fitting the GaIIλ1414, and GaIIIλλ1495, 1534 lines with synthetic spectra computed under the conventional assumptions of local ther…
The ISO-SWS spectrum of P Cygni.
Waters, L. B. F. M.; Hillier, D. J.; Kudritzki, R. P. +8 more
The free-free IR excess and the IR emission lines of H and He I of the Luminous Blue Variable P Cygni are observed with the ISO-SWS instrument. The observed profiles and the free-free emission are compared with predictions from a non-LTE model atmosphere with a stellar wind. The observations agree very well with a model that has the following prop…
LWS-spectroscopy of Herbig Haro objects and molecular outflows in the Cha II dark cloud.
Ade, P. A. R.; Liseau, R.; White, G. J. +34 more
We present the first far infrared spectra of the Herbig Haro objects HH 52-53-54 and of IRAS 12496-7650, all located in the nearby star forming region known as Chamaleon II dark cloud, obtained with the Long Wavelength Spectrometer (LWS) onboard the Infrared Space Observatory (ISO). The richest spectrum is found in HH 54, showing molecular transit…
HST and groundbased observations of the `Hubble-Sandage' variables in M 31 and M 33.
Stahl, O.; Davidson, K.; Humphreys, R. M. +4 more
The small group of peculiar stars known as the Hubble-Sandage variables in M 31 and M 33 belong to the class of stars we now call the Luminous Blue Variables - highly unstable, evolved massive stars found in many spiral and irregular galaxies. We have used the Hubble Space Telescope to obtain UV imaging and spectroscopy of several of the LBVs in M…
Photoionization resonances of SiII in stellar spectra.
Lanz, T.; Artru, M. -C.; Hubeny, I. +1 more
We have studied the influence of the Si^+^ photoionization on stellar atmospheres. Recent calculations using the R-matrix code provide detailed cross-sections with autoionization resonances for the first 50 energy levels of Si^+^. These photoionization cross-sections are included in the calculation of the far ultraviolet synthetic spectrum of A an…