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The influence of suprathermal electrons on the derivation of coronal electron temperatures from solar wind minor ion charge states

Wurz, P.; Bochsler, P.; Ipavich, F. M. +6 more

Rigidity Dependence of Near-Earth Latitudinal Proton Density Gradients

Potgieter, M. S.; Heber, B.; Burger, R. A.

The rigidity dependence of the latitudinal gradient of cosmic-ray protons observed by Ulysses poses a challenge to modulation models: it increases as function of rigidity up to about 1.4 GV and then decreases. Although models could reproduce the observed small positive gradient for an A > 0 solar polarity cycle, its maximum was at a rigidity we…

ISO Far-Infrared Deep Survey of the Lockman Hole

Kawara, K.; Taniguchi, Y.; Matsuhara, H.

HR 211 From Maple Observatory and Hipparcos

Thompson, Raymond R.

Starting in October 1993, HR 211 was observed photoelectrically in V on 76 nights over 5 years. The complete light curve and the power spectrum reveal a period close to a month with a possible long-term variability present. This is compares with the Hipparcos wide-band photometry, which runs from December, 1989, to February, 1993, and consists of …

Early Radio Positions of Stars

Assafin, M.; Andrei, A. H.; Puliaev, S. P. +3 more

Early radio positions for a sample of 100 Hipparcos stars, three Tycho-only stars, and nine radio stars with optical positions referred to the Hipparcos/ICRS frame are analyzed. The optical proper motions are used to compare the optical and radio positions. From an original sample of 247 radio positions for the above 112 stars, a set of 220 shows …

Time-resolved spectroscopyHiifill of the peculiar Hα variable Be star HD 76534

Drew, Janet E.; Oudmaijer, René D.

We present time-resolved spectroscopy of the Be star HD 76534, which was observed to have an Hα outburst in 1995, when the line went from photospheric absorption to emission at a level of more than two times the continuum within 2.5 hours. To investigate the short-term behaviour of the spectrum of HD 76534 we have obtained 30 spectra within two ho…

Galaxies at High Redshift

Illingworth, Garth

Within just the last few years, we have advanced from knowing only a few galaxies at z>2 to having redshifts for nearly 1000 z ∼ 2–5objects. The majority of this sample has been detected through the photometric `drop-out' technique used so successfully by Steidel and his collaborators. In addition, a handful of objects have already been detecte…

The Origin of QSO Mg II λ 2796 Lines

Danks, A. C.

We have started a systematic spectroscopic survey of stars in the η Carina nebula using the echelle mode of the Space Telescope Imaging Spectrograph (STIS). The Mg II λ2796/λ2803 lines seen in our R ∼ 100000, spectra of the star CPD–59^° 2603 show a remarkable similarity with the intervening Mg II system seen in QSO absorption spectra. S…

Working Group 3 Report: Coronal Hole Boundaries and Interactions with Adjacent Regions

Esser, R.

Summarized below are the discussions of working group 3 on "Coronal hole boundaries and interactions with adjacent regions" which took place at the 7th SOHO workshop in Northeast Harbor, Maine, USA, 28 September to 1 October 1998. A number of recent observational and theoretical results were presented during the discussions to shed light on differ…

A Second Catalog of Orbiting Astronomical Observatory 2 Filter Photometry: Ultraviolet Photometry of 614 Stars

Meade, Marilyn R.

Ultraviolet photometry from the Wisconsin Experiment Package on the Orbiting Astronomical Observatory 2 (OAO 2) is presented for 614 stars. Previously unpublished magnitudes from 12 filter bandpasses with wavelengths ranging from 1330 to 4250 Å have been placed on the white dwarf model atmosphere absolute flux scale. The fluxes were converted to m…