Search Publications

On the minimum fluxes of low-energy ions (0.5 MeV/nuc - 8 MeV/nuc) at high heliospheric latitudes

Krupp, N.; Keppler, E.; Fraenz, M. +3 more

The quiet-time fluxes of ions from 0.5 MeV/nuc to 7 MeV/nuc (for oxygen) have been studied for the time period between mid-1993 through the first 104 days of 1994. During this time period Ulysses was below the heliographic current sheet. We find that at the quietest times, the ion population is dominated by the ACR component. For more active times…

The application of network synthesis to repeating classical gamma-ray bursts

Hurley, K.; Kouveliotou, C.; Laros, J. +3 more

It has been suggested that the BATSE gamma-ray burst catalog contains several groups of bursts clustered in space or in space and time, which provide evidence that a substantial fraction of the classical gamma-ray burst sources repeat. Because many of the bursts in these groups are weak, they are not directly detected by the Ulysses GRB experiment…

Photographic observations of visual double stars.

Jasinta, D. M. D.; Raharto, M.; Soegiartini, E.

We present the results of photographic observations of 399 visual double stars of the Hipparcos Input Catalogue (HIC), observed in the years 1980 and 1990-1991 with the 60-cm double-refractor of the Bosscha Observatory at Lembang, Java.

IUE Echelle Observations of the Photospheres and Circumstellar Environments of Hot White Dwarfs

Holberg, J. B.

Hubble Space Telescope Imaging of the Wind-blown Lobe NGC 6165

O'Neil, Earl J., Jr.; Scowen, Paul; Lynds, C. Roger +3 more

We have used the Hubble Space Telescope wide field/planetary camera to study the structure of the bipolar nebular NGC 6164/6165. Our study concentrates on the structure of a number of small clumps of material embedded within the southern lobe of the system (NGC 6165). These knots have a cometary appearance, with bright surfaces facing the central …

Nucleon Modulation from the ULYSSES Rapid Latitude Scan: COSPIN/KET Results

Sierks, H.; Kunow, H.; Wibberenz, G. +11 more

The Secondary Star in AM CVn

Solheim, J. -E.; Nymark, T. K.

The spectrum of AM CVn shows no definite sign of a secondary star, but through black body calculations of the spectra of the primary, disc and secondary objects, we find that if a one-temperature model for the secondary is assumed, a secondary which is cooler than 5000 K may be present without being seen in the spectrum. There is some excess flux …

Exposed white dwarfs in dwarf novae

Sion, Edward M.

Hubble Space Telescope far ultraviolet spectroscopic observations of cataclysmic variable white dwarfs, exposed during dwarf nova quiescence, have yielded a number of new insights on accretional heating, photospheric abundances of the accreted atmosphere and rotational velocities of the underlying degenerates. Recent results of synthetic spectral …

Spectroscopy of B Stars in the Small and Large Magellanic Clouds

Rolleston, W. R. J.

High-resolution spectroscopic observations of B-type stars in the Small (SMC) and Large (LMC) Magellanic Clouds have been obtained using the UCL echelle spectrograph at the Anglo-Australian Telescope. Preliminary results of an LTE model-atmosphere analysis are presented for three stars in the LMC, together with the results of a similar analysis of…

Interstellar Ultraviolet Extinction Towards the Nitrogen Sequence Wolf-Rayet Stars

Niedzielski, Andrzej

With the archive IUE spectra of WR stars collected by Niedzielski and Rochowicz (1994) we obtain the UV extinction curve for WN stars. Using the two-color diagram method we can reach the goal almost independently, assuming only similar (b-v)_0 for all single galactic WN stars, what is discussed on the basis of latest results. The resulting extinct…