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Evidence for Absorption in NGC 1068

Boksenberg, A.; Catchpole, R. M.

We present evidence that interstellar absorption is responsible for producing much of the complex morphology seen in the inner few arcseconds of NGC 1068.

HST WFPC2 Line and Continuum Images of NGC 1068

Ford, H. C.; Kriss, G. A.; Tsvetanov, Z. I. +1 more

ISO-SWS Spectra of AGB Stars

Waters, L. B. F. M.; Justtanont, K.; Yamamura, I. +1 more

In this contribution, we present a few highlights of the guaranteed time program to observe AGB stars with differing chemical compositions and mass loss rates using ISO¹ SWS. We briefly discuss C₂H₂ absorption in C-stars and O-rich stars with the 13 µm dust emission.

A Compact Circumstellar Dust Envelope of an Evolved AGB Star IRC-10529

Izumiura, H.; Hashimoto, O.

We have made far-infrared mapping observations around a heavily mass losing evolved star IRC-10529 with ISO. It is found that IRC-10529 shows a very compact circumstellar dust envelope in the 60 and 90 µm images obtained by ISOPHOT. Such a small size of the circumstellar dust envelope indicates very short history of the present strong mass loss. I…

Clumpy Structure and Polarization in NGC 1068

Kishimoto, M.

The polarization map from the HST archival data of the imaging polarimetry for NGC 1068 is analyzed. In the HST images, the central few arcsecond region seems to consist of several clumps, and if we extract the polarization of the clumps separately, the viewing angle of each clump can be determined. This enables us to have a three-dimensional view…

Dust Features of Visually Bright AGB Variables as Seen by ISO and IRAS

Loidl, Rita; Hron, Josef; Kerschbaum, Franz

ISO-SWS spectra of two Mira variables (R Cas and T Dra), taken at two different pulsational phases, are presented. We describe the reduction of the data and the encountered problems. The dust features observed by ISO at different phases and with the Low Resolution Spectrometer of IRAS are compared. We briefly discuss the results in terms of curren…

IUE observations of star formation in a cooling flow

Hansen, L.; JØrgensen, H. E.; NØrgaard-Nielsen, H. U.

Star formation in cooling flows is usually found to have an initial mass function deficient in massive stars, but the center of the cooling flow in Hydra A has been shown to contain a significant number of early type stars. Here we use UV-spectra obtained with the IUE satellite together with ground based data to constrain the nature of this young …

Giantic Roundchroms of Binary Systems SX CAS and 22 VUL

Gurzadyan, G. A.

The IUE observations do not favor the chromospheric origin of typical chromospheric emission lines, of the doublet 2800 MgII first of all, in close binary systems SX Cas and 22 Vul, both with a cool giant-supergiant as primary, and a hot B7–B8 star as secondary. Here, it is shown that the concept of common chromospheres – roundchroms can explain t…

Revised chemical models of ζ Oph based on HST data

Williams, D. A.; Wagenblast, R.

Hubble Space Telescope observations by Savage, Cardelli and Sofia (1992) and Cardelliet al. (1993) have led to improved gas phase abundances for many elements in the diffuse cloud towards the star ζ Oph. Most remarkably, it was found that oxygen is much more strongly depleted than previousCopernicus observations indicated. As a consequence, chemic…

Detection of langmuir solitons: implications for type III burst emission mechanisms at 2ω _PE

Goldstein, M. L.; Stone, R. G.; Thejappa, G.

We present the experimental verification of existing theoretical models of emission mechanisms of solar type III bursts at the second harmonic of the plasma frequency, ω_pe. This study is based on the detection of Langmuir and envelope solitons by the Ulysses spacecraft inside three type III burst source regions. We show that the oscilla…