Search Publications

PAH's and Crystalline Silicates in Planetary Nebulae

Beintema, D. A.

An overview is given of the PAH and crystalline silicate emissions seen in the SWS guaranteed-time programme on planetary nebulae. Of the 9 objects on which good continuum measurements were obtained above 29 µm, 7 show evidence of olivine emission at 33.5 µm. PAH emission is seen in 5 of these objects, 3 objects show both PAH's and olivines. The p…

Molecules in AGB Stars Observed with ISO

Cernicharo, J.

I present in this review the recent results obtained with ISO concerning gas phase molecules in evolved stars. The near, medium and far-infrared spectrum of C-rich and O-rich stars can provide a very important information on the molecular content of these objects. Detailed models for the envelopes of AGB stars are also presented. I also report the…

ISO Observations of Wolf-Rayet Dust Shells

Morris, P. W.; van der Hucht, K. A.; Williams, P. M.

Observations of circumstellar dust clouds of Wolf-Rayet stars made with the Short Wavelength Spectrometer on ISO reveal a subtle variety of spectral energy distributions not evident from ground-based observations. The modelling of these using the radiative transfer code "Dusty" by Ivezić, Nenkova & Elitzur is reported. The results are used to …

ISO-SWS Observations of the Time Variability of Oxygen-righ Mira Variables

Izumiura, H.; Onaka, T.; Tanabé, T. +3 more

We present the first observation of variation of the infrared spectrum of circumstellar dust emission around an oxygen-rich Mira variable star, Z Cyg, over an entire light variation cycle, based on the periodic SWS01 observations. The 10 µm and 20 µm ‘silicate features’ become stronger relative to the photospheric emission at maximum that at minim…

ISO SWS Spectroscopy of WR 146 (WC6+O)

Crowther, P. A.; Willis, A. J.; Morris, P. W. +2 more

We have obtained ISO SWS spectroscopy of WR 146 (WC6+O) covering the wavelength range 2.6-20 µm. WC6 wind emission is observed in numerous lines of He II and C IV, as well as in the [Ne III] 15.5 µm line, but not in [Ne II] 12.81 or [Ne V] 14.32 µm. An analysis of these spectra (and complementary radio and optical data) yields for the WC6 star: v∞…

Search for H2 Emission from Disks around T Tauri and Herbig AE Stars

Thi, W. F.; van Dishoeck, E. F.; Blake, G. A. +4 more

Preliminary results are presented of observations of the pure rotational lines of H2 toward T Tauri and Herbig Ae stars using the Short Wavelength Spectrometer (SWS) on the Infrared Space Observatory (ISO). The sources are selected to be isolated low- and intermediate-mass young stellar objects, for which the presence of a circumstellar disk has b…

ISOCAM Imaging of LBVS

Waters, L. B. F. M.; Trams, N. R.; Voors, R. H. M.

PDRS and Shocks in S106 IR and CEP a East

Waters, L. B. F. M.; Tielens, A. G. G. M.; van den Ancker, M. E. +1 more

We present SWS grating scans of pure H2 rotational lines, as well as several infrared fine-structure lines for two embedded Young Stellar Objects, S106 IR and Cep A East. Excitation temperatures and masses were derived from the low-lying pure rotational levels of H2 and are 490 and 740 K and 0.04 and 0.007 M⊙ for S106 and Cep A, respectively. The …

Dramatic change in Sakurai's Object

Roth, M.; Kimeswenger, S.; Kerber, F. +1 more

Vega-like Stars: Grain Removal, Replenishment and Recent ISO Observations

Dominik, C.; Hjhvega Consortium