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Distance Scales After HIPPARCOS

Feast, M. W.

A general review is given of the use of Hipparcos data to calibrate basic distance indicators.

Crowded-field photometry from HST-imaging

Thomsen, B.; Sodemann, M.

We present a thorough investigation of stellar photometry based on HST imaging of crowded fields at 85arcsec and 10arcsec from the centre of the high-surface brightness elliptical galaxy M 32. The Principal Investigators of the present archive data have elsewhere presented an impressive colour-magnitude diagram of the field at 85arcsec . Based on …

Infrared Observations of High-Mass X-Ray Binaries

Waters, L. B. F. M.; van Loon, J. Th.; Kaper, L. +2 more

We present the first results of our ISO program on High-Mass X-ray Binaries (HMXBs). Infrared photometry, obtained at different aspect angles of the systems, is used to investigate the massive star's disrupted stellar wind and the accretion flow towards the compact X-ray source. Scenarios for massive binary evolution predict that HMXBs receive a l…

ISOPHOT Observations of the RS CVN -Type Star HR 7428

Pagano, I.; Messina, S.; Rodonò, M. +3 more

Dust Emission from AGB Stars ISO-SWS Observations of Long-Period Variables

Hron, J.; Kerschbaum, F.; Aringer, B.

Sensitivity of Low Frequency Oscillations to Updated Solar Models

Provost, J.; Berthomieu, G.; Morel, P.

A large number of acoustic frequencies have already been detected, leading to a "seismic" model of the Sun rather close to the actual standard solar models. The core however is not yet well constrained by these observations and frequencies of low degree, low frequency modes which penetrate deeply into the solar core are needed. We present here a s…

Measurement of 0-25 eV Ions With a Retarding Potential Analyzer on the Cluster Ion Spectroscopy Experiment

McCarthy, M. P.; McFadden, J. P.

We describe a retarding potential analyzer (RPA) which extends the energy range of the Cluster ion spectroscopy (CIS) experiment down to 0-25 eV [Rème et al., 1993]. The CIS experiment will make comprehensive measurements of 3D ion distribution functions from 0-40 keV over the broad range of plasma regions the Cluster orbit will traverse. Mass com…

Rotationally Broadened Synthetic Spectra for HST and IUE Observations of Exposed White Dwarfs in Cataclysmic Variables

Sion, E. M.; Nguyen, Quyen; Fabian, Dirk +2 more

In many dwarf novae during quiescence, the underlying white dwarf dominates the flux in the far ultraviolet. By observing these exposed degenerate stars with the Hubble Space Telescope Goddard High Resolution Spectrograph and Faint Object Spectrograph (HST GHRS and FOS), the white-dwarf rotation rates can be determined or constrained by fitting sy…

Comment on: “Polar plumes and fine-scale coronal structures — On the interpretation of coronal radio sounding data” by Pätzold and Bird

Habbal, Shadia Rifai; Woo, Richard

Reduction of the Astrographic Catalogue, zone of S. Fernando

Vieira, K.; Abad, C.; Zambrano, A.

The San Fernando Zone of the Astrographic Catalogue is reduced to the HIPPARCOS system in order to test a reduction model previously presented by Abad (1993). A new method for the determination of field distortion and magnitude or color dependent systematic errors on photographic plates is discussed.