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Phase-resolved Hubble Space Telescope ultraviolet spectroscopy of V795 HER
Prinja, R. K.; Mason, K. O.; Howell, S. B. +2 more
We present highly time-resolved HST FOS UV spectroscopy of the nova-like binary V795 Her. Several key results emerge. For the first time we find a strong 2.6-h signature in the variability of the UV lines. The HST data reveal no evidence of a 4.8-h `period', in contrast to our previous IUE observations. This, and differences in the spectral line c…
The HIPPARCOS solar system objects catalogues
Lindegren, L.; Mignard, F.; Hestroffer, D. +3 more
Astrometric and photometric measurements of a number of solar system objects were performed by the Hipparcos satellite in both the Hipparcos main mission and the Tycho experiment. The results concern mainly asteroids but also the planetary satellites Europa, Ganymede, Callisto, Titan and Iapetus, and the major planets Uranus and Neptune. The speci…
Interstellar pickup hydrogen observations at large heliocentric distances
Gazis, P. R.; Mihalov, J. D.
Possible signatures of interstellar pickup hydrogen have been identified in data from the Pioneer 10 and 11 Ames plasma analyzers at locations out to beyond the orbit of Saturn, and at a wide range of longitudes in the heliosphere, both upstream and downstream in the interstellar wind. These signatures provide an extension of pickup ion observatio…
Atomic Data and Spectral Line Intensities for Mg VIII
Bhatia, A. K.; Thomas, Roger J.
EUV spectral lines of Mg VIII have been observed from the solar corona by Skylab, SERTS, and more recently by SOHO. Atomic data for this astrophysically important ion are presented in this paper. The atomic data include energy levels, oscillator strengths, transition rates, and electron-impact excitation collision strengths. Twenty levels are incl…
Galaxies with Spiral Structure up to Z ~ 0.87: Limits on M/L and the Stellar Velocity Dispersion
Quillen, A. C.; Sarajedini, V. L.
We consider seven distant galaxies with clearly evident spiral structure from Hubble Space Telescope images. We place upper limits on their mass-to-light ratios (M/L) by computing M/L_B for a maximal disk. We find that these galaxies have maximal-disk mass-to-light ratios M/L_B = 1.5-3.5 (M/L_B)_⊙ at the low end, but within the range seen in nearb…
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∞…
ORFEUS II Far-Ultraviolet Observations of the Lunar Atmosphere
Flynn, B.
In 1996 November and December, remote FUV observations of the lunar atmosphere were conducted using the Berkeley spectrograph aboard the ORFEUS-SPAS II satellite. The main goal of the observations was to measure the distribution of Ar above the lunar dayside for the first time and to search for another predicted atmospheric constituent, Ne. During…
Lower bound for electron core beta in the solar wind
Goldstein, Bruce E.; Gary, S. Peter; Newbury, Jennifer A.
Solar wind electrons, especially under conditions of relatively low speed flow, often can be represented as two bi-Maxwellian components, a cooler, more dense core (denoted by the subscript c) and a hotter, more tenuous halo. Solar wind observations from Ulysses between 1.5 and 2 AU further indicate that the β for electron core temperatures parall…
The Chamaeleon infrared nebula revisited. Infrared imaging and spectroscopy of a young stellar object
Henning, Thomas; Feldt, Markus; Lagage, Pierre O. +3 more
We are presenting spectroscopic and imaging data on the Chamaeleon Infrared Nebula (Cha IRN). Imaging was done between 1 and 2.5mu m and at 10mu m. Spectra of the object were obtained in the 2.1mu m - 4.6mu m range by ground-based measurements as well as using ISOPHOT-S in the 2.5mu m - 11.6mu m range. By combining these data with a K-band speckle…
Lyalpha absorbers at z<= 1: HST-CFHT imaging and spectroscopy in the field of 3C 286
Bergeron, J.; Le Brun, V.
We present further observational results on our Lyalpha -only absorber identification project at low and intermediate redshifts. We combine CFHT/MOS imaging and spectroscopic observations of 25 galaxies in the field of the quasar 3C 286 (z_e = 0.849) with HST/FOS spectrum of the quasar between 1600 and 3000 Angstroms and HST/WFPC2 high spatial res…