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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 …

On the use of HIPPARCOS data for the determination of astrometric positions of outer planets

Fienga, Agnes

We investigated the improvement of observed astrometric positions of outer planets by use of Hipparcos Catalogue stars and satellite measurements. Positions of Jupiter from photographic plates were obtained, indirectly, from measurements of the Galilean satellites, using the G5 ephemerides of Bureau des Longitudes. The use of Hipparcos data in the…

Fe II emission lines in the UV spectrum of Sirius-A and VEGA

Ferlet, R.; Vidal-Madjar, A.; Lanz, T. +4 more

We present high-quality HST/GHRS spectra in the Hydrogen Lalpha spectral region of Vega and Sirius-A. Thanks to the signal-to-noise ratio achieved in these observations and to the similarity of the two spectra, we found clear evidence of emission features in the low flux region, lambda lambda 1190-1222 Angstroms. These emission lines can be attrib…

The IUE Spectrum, Electron Density, and Terminal Wind Velocity of the ``O VI Sequence'' Planetary Nebula NGC 5315

Feibelman, Walter A.

Extensive archival and new IUE data obtained during the last (19th) year episode of the ``O VI sequence'' planetary nebula NGC 5315 and its central star have been analyzed. A large number of high-excitation emission lines have been identified, and their fluxes were determined. These yield electron densities from C III], Si III], and N III], and te…

Ulysses observations of field-perpendicular plasma flows in the Jovian magnetosphere: comparison of ExB velocity vectors derived from energetic ion and thermal electron data

Balogh, A.; McComas, D. J.; Dunlop, M. W. +4 more

The ExB velocity vectors which correspond to the field-perpendicular flow of the low-energy plasma have been independently derived for the Ulysses flyby of Jupiter using energetic ion and thermal electron data. In this paper these measurements are compared. It is shown that reasonable quantitative agreement exists during the prenoon inbound pass, …

The O V 1213.9 Angstroms forbidden line in the quiet Sun

Curdt, W.; Mathioudakis, M.; Keenan, F. P. +2 more

We present the first unambiguous detection of the O v 1213.9 Angstrom (2s(2) (1) S_0 -> 2s2p (3) P_2) forbidden line in the solar spectrum, using observations obtained with the SUMER instrument on board SOHO. The wavelength separation of the forbidden to the (2s(2) (1) S_0 -> 2s2p (3) P_1) intercombination line at 1218.35 Angstroms is 4.5+/-…

IUE low-resolution observations of the triple system CHCygni: the mass transfer in the symbiotic pair

Bode, M. F.; Drechsel, H.; Skopal, A. +1 more

We present and analyse UV low-resolution spectra of CHCyg taken during the whole period of the International Ultraviolet Explorer (IUE) mission. Our analysis of the variation in the UV/optical hot star continuum confirmed the basic scenario of sporadic accretion in the symbiotic pair of the triple-star system as being responsible for maintaining i…

Analysis Methods for Multi-Spacecraft Data. ISSI Scientific Reports Series SR-001, ESA/ISSI, Vol. 1. ISBN 1608-280X, 1998

Daly, Patrick W.; Paschmann, Götz

[\ion(C)(ii)] 158 and [\ion(O)(i)] 63 MU M ISO-Observations of L1457

Timmermann, Ralf; Koester, Benedikt; Stutzki, Juergen

We report here the results of [C Ii] 158 and [O I] 63 mu m fine-structure line observations along two cuts across a molecular clump of L1457 (MBM 12) carried out with ISO-LWS. [C Ii] emission was detected at all positions observed. It can be assigned to the cooling of the diffuse atomic interstellar medium. We observed excess [C Ii] emission from …

A Nearby Galaxy in the Deep-Ultraviolet: Voyager 2 Observations of M33 from Lyα to the Lyman Limit

Keel, William C.

Observations of high-redshift galaxies in the emitted-wavelength regime around Lyα have renewed interest in the appearance of normal galaxies in the deep ultraviolet. This paper presents an analysis of spectrophotometry of the local Sc galaxy Messier 33 (NGC 598) obtained by Voyager 2, covering the range from below the Lyman limit to about 1250 Å.…