Search Publications
The '10-hour' Modulation of the Jovian Electron Spectrum in Interplanetary Space-Ulysses Observations
Ferrando, P.; Raviart, A.; Ducros, R. +1 more
A global analysis method for astrolabe observations
Chollet, F.
In a previous paper (Chollet & Najid 1992), we gave the general principles of a new global method to analyze the astrolabe observations. The fundamental equation was obtained from the classical one in which the corrections to the star positions at the observational epoch are replaced by developments that contain the corrections to the star pos…
Observations of 0.3 to 2.0 MeV Protons in the 1 to 5 AU Region with Voyager 1 and Ulysses Compared to IMP 8
Armstrong, T.; Boufaida, M.
Calibration of Hipparcos Long Period Variable Start Fields Using Multi-Color CCD Observations
Howell, Steve B.; Mattei, Janet; Benson, Priscilla J. +1 more
The first set of 4-color AAVSO CCD finder charts has been prepared using the 0.9-m telescope at Kitt peak national Observatory in Arizona. The stars selected were northern long period variable stars observed with the Hipparcos astrometric satellite, since multicolor photometry was needed on these stars to calibrate and reduce the photometric and a…
Precise measurement of the right ascension of the Geminga pulsar using COS-B data.
Li, T. P.; Cheng, L. X.; Ma, Y. Q. +2 more
We have obtained a more precise value of the right ascension and a new spin evolution law of the Geminga pulsar using COS-B data on the assumption 0r high stability of the absolute phase. The new value is a(1950)=6h30m59s .057, with error about 0.5 arcsec, compared with the 3.2 arcsecs from the Einstein HRI result.…
Comparisons of IUE & HST ultraviolet spectra of extragalactic H II regions.
Terlevich, E.; Terlevich, R.; Garnett, D. R. +5 more
The authors compare recently obtained HST FOS and IUE SWP ultraviolet spectra of two extragalactic H II regions: SBS 0335-052 and 30 Doradus in the LMC. They also present IUE SWP NEWSIPS processed spectra of I Zw 18, which show significant improvements in the data quality, suggesting that reprocessed IUE archival spectra will offer enhanced scienc…
Model Atmospheres: Tool for Identifying Interstellar Features
Frisch, P. C.; Slojkowski, S. E.; Rodriguez-Bell, T. +1 more
Model atmosphere parameters are derived for 14 early A stars with rotation velocities, from optical spectra, in excess of 80 km/s. The models are compared with IUE observations of the stars in regions where interstellar lines are expected. In general, with the assumption of solar abundances, excellent fits are obtained in regions longward of 2580 …
The Ultraviolet Spectrum of the Binary System Ty-Pyxidis
Danezis, E.; Theodossiou, E.; Antonopoulou, E.
A detailed list and analysis of line identifications of five UV spectra of the RS CVn-type binary system TY Pyxidis are presented. These spectra are recorded at different phases with the International Ultraviolet Explorer (IUE). Two of them are in the wavelength rangeλλ1235–1950 Å while the other three in the rangeλλ2700–3110 Å. The far-UV spectru…
Anisotropy measurements and spectra from a solar proton event in March 1991
Balogh, A.; Forsyth, R. J.; Cowley, S. W. H. +2 more
We use observations from the Anisotropy Telescopes on the Ulysses spacecraft to determine the omnidirectional flux profile of protons in the energy range 0.7 - 1.3 MeV, during the solar proton event that began on 23 Mar 1991. We also show the spectral index throughout the event at 0.7 - 2.2 MeV and at 2.2 - 6.5 MeV, with three example spectra, one…
Gas dynamics of solar wind interaction with interstellar gas: theory and experiment.
Baranov, V. B.
A survey of the current situation in gas dynamic models of solar wind interaction with the local interstellar medium (LISM) is presented. The role of these models in interpreting a number of observed physical phenomena is investigated. Attention is concentrated on the self-consistent gas dynamic model of solar wind interaction with the supersonic …