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Transonic Decretion Discs Around be Stars

Okazaki, A. T.

ISO-SWS Observations of Stars with Unusual IRAS LRS Characteristics

Deguchi, S.; Mizutani, M.; Yamamura, Y.

Observations of 5 stellar sources with unusual characteristics of IRAS Low Resolution Spectra were made with the SWS on ISO. Observed stars are 4 late-type stars with silicate bands and one planetary nebula. Their IRAS LRS contain somewhat unusual features in respect of the 10/18 µm intensity ratio or narrow emission feature from unknown molecular…

Absorption Features of Ices Toward NGC7538 IRS1

Leto, G.; Strazzulla, G.; Nisini, B. +2 more

In this paper we present a comparison of the observed absorption band at about 660 cm-1 (15.1 µm) toward NGC7538 IRS1 attributed to the bending mode of solid CO2 with laboratory spectra of ion irradiated mixtures.

Bi-Dimensional Spectrography at HST-Like Spatial Resolution: [OIII] Kinematics and Ionization in the NLR of NGC 1068

Binette, L.; Wilson, A. S.; Ferruit, P. +1 more

We present a study at HST-like spatial resolution of the gas kinematics in the innermost part of NGC 1068. This work is based on observations with the integral field spectrograph TIGER mounted on the CFH Telescope. We first derived the final spatial PSF of our data and checked its photometric integrity by comparison with two independent [OIII] HST…

ISO-SWS Observations of NGC 1068

Lutz, D.; Genzel, R.; Sturm, E. +2 more

We present a first analysis of 2.4-45µm spectra of NGC 1068 obtained with the Short Wavelength Spectrometer SWS on board the Infrared Space Observatory ISO. The measured fine-structure line fluxes can be fit successfully by a simple photoionization model invoking an EUV bump in the ionizing continuum, similar to the case of the Circinus galaxy. Di…

The Location of the Nucleus of NGC 1068 from HST Imaging Polarimetry and Absolute Astrometry

Macchetto, F. D.; Capetti, A.; Lattanzi, M. G.

We present the results of a program to obtain an accurate (better than 100 mas) astrometry of HST images of NGC 1068 and consequently a direct registration with radio images. The optical peak seen in the HST images is located at α = 02h42m40.711s, δ = -00°00'47.81 (J2000, FK5), with an error of 80 mas. The hidden nucleus, as determined by HST imag…

Circumstellar PAHs and Carbon Stardust

Tielens, A. G. G. M.

The SWS on ISO has revealed the incredible richness of IR emission features in the spectra of post-AGB objects and planetary nebulae. Besides the well known features at 3.3, 6.2, 7.7, 8.6, and 11.3 µm, a wealth of weaker features is present as well. These studies also reveal detailed variations from source to source, which may be of key impo…

The Jet Driven Motions in the Narrow Line Region of NGC 1068

Robinson, Andrew; Axon, David J.; Marconi, A. +2 more

We have obtained HST FOC f/48 long-slit spectroscopy of the central 2 arcseconds of the Narrow Line Region of NGC 1068 between 3500-5400\OA with a spectral resolution of 1.78\OA/pixel. At a spatial scale of 0″.0287 per pixel these data provide an order of magnitude improvement in resolution over previous ground based spectra and allow us to trace …

ISO LWS Observations of Evolved Stars and Nebulae

Barlow, M. J.

Synthetic Spectra of Long-Period Variables: A First Comparison with ISO Observations

Aringer, Bernhard; Loidl, Rita; Hron, Josef +3 more

Exploratory synthetic spectra were computed for carbon-rich long-period variables. We used dynamic model atmospheres of Höfner & Dorfi (1997) and calculated partial pressures, absorption- and scattering coefficients as input for the spectral synthesis code of Jørgensen et al. (1992). First ISO SWS-observations of the carbon-Mira T Dra are comp…