Search Publications
HD 129333: The Sun in Its Infancy
Guinan, Edward F.; Dorren, J. David
HD 129333 is a remarkable young, nearby solar-type G star which offers a unique opportunity of studying the properties of the Sun at a time very shortly after in arrived on the main sequence. Its space motion suggest that it is a member of the Pleiades moving group, with an age of approximately 70 Myr; its lithium abundance is consistent with this…
Direction finding study of Jovian hectometric and broadband kilometric radio emissions: evidence for their auroral origin
Zarka, P.; Ladreiter, H. P.; Lacacheux, A.
Taking advantage of the direction finding capabilities of the Ulysses unified radio and plasma wave (URAP) experiment we derive the source locations and emission characteristics of the Jovian hectometric (HOM) and broadband kilometric (bKOM) emissions. Unlike previous studies we additionally determine the systematic error of the source direction d…
Galaxies with Extreme Infrared and Fe II Emission. II. IRAS 07598+6508: A Starburst/Young Broad Absorption Line QSO
Lipari, Sebastian
In this paper we investigate the nuclear properties of the extreme IR- Fe II emitters IRAS 07598+6508 by means of UV-optical spectroscopy, and IR photometry. The features shown in the UV region (by the IUE spectrum of IRAS 07598+6508) are very similar to those obtained for high-redshift low-ionization BAL QSOs (i.e., they show a strong blend of br…
Photometric and spectroscopic studies of cool stars discovered in EXOSAT X-ray images II. Lithium abundances
Tagliaferri, G.; Pasquini, L.; Pallavicini, R. +2 more
We present high-resolution spectra in the Li I 6708 A region, and multicolor photometry, for a sample of active stars detected serendipitously by the EXOSAT satellite. We analyse the spectral data with a spectral synthesis code and derive Li abundances, rotation rates and metallicities. We use our multicolor photometry to infer the spectral classi…
Tomographic Separation of Composite Spectra. II. The Components of 29 UW Canis Majoris
Wiggs, Michael S.; Gies, Douglas R.; Bagnuolo, William G., Jr. +2 more
We have analyzed the UV photospheric lines of 29 CMa, a 4.39 day period, double-lined O-type spectroscopic binary. Archival data from International Ultraviolet Explorer (IUE)(28 spectra well distributed in oribital phase) were analyzed with several techniques. We find that the mass ratio is q = 1.20 +/- 0.16 (secondary more massive) based on three…
Sub-arcsecond 2D photometry and spectroscopy of the nucleus of M 31 : the supermassive black hole revisited.
Emsellem, E.; Bacon, R.; Monnet, G. +1 more
Sub-arcsecond imagery (HRCAM, 0.35" - 0.57" FWHM) and two- dimensional spectrography (TIGER, 0.9" FWHM) of the central nucleus of M 31 have been obtained at CFHT. The photometric data clearly show the double-peaked nucleus, in excellent agreement with a recent HST image by Lauer et al. (1993). We built deconvolved surface brightness models, using …
3-D Simulation of high-latitude interaction regions: Comparison with Ulysses results
Gosling, J. T.; Pizzo, V. J.
A three-dimensional (3-D) magnetohydrodynamic (MHD) numerical model is used to simulate the global evolution of a steady, tilted-dipole solar wind flow configuration similar to that prevalent in interplanetary space in 1993. Systematic latitudinal changes in the structure of a corotating interaction region (CIR) near 5 AU is shown to agree well wi…
The Abundance of Interstellar Oxygen toward Orion: Evidence for Recent Infall?
Meyer, David M.; Jura, M.; Cardelli, Jason A. +1 more
We present high S/N (greater than 800) Goddard High-Resolution Spectrograph (GHRS) observations of the weak interstellar O I lambda 1356 absorption in the low-density sight lines toward iota Ori and kappa Ori. By comparing these data with observations toward more reddened stars, we find no evidence of density-dependent depletion from the gas phase…
Methanol and hydrogen sulfide in comet P/Halley.
Eberhardt, P.; Meier, R.; Krankowsky, D. +1 more
The Neutral Mass Spectrometer on the Giotto spacecraft measured the gas and ion composition in the coma of comet P/Halley. A detailed model of the ion chemistry inside the contact surface located at 4660 km is used to interpret the measured ion density profiles in the 32 to 35 amu/e mass range. The masses 33 and 35 amu/e are dominated by the proto…
Galaxies with Extreme Infrared and Fe II Emission. I. Markarian 231: The Signature of a Young Infrared QSO
Colina, Luis; Macchetto, F.; Lipari, Sebastian
We investigate the ultraluminous IR Galaxy/QSO Mrk 231 by means of long-slit optical spectroscopy, high spatial resolution broad-band optical imaging and UV IUE spectra. The spectrum shows an extreme Fe II optical emission (Fe II_OPT_/Hβ ~ 8), broad Balmer and Na ID lines, weak high-excitation lines, double-peaked optical narrow emission lines wit…