Search Publications
Testing a Coupling Relation between Visible and Dark Matter in the MS 2137-2353 Cluster Core
Giraud, Edmond
The empirical coupling relation in Md=γM1/2r between the halo dark mass distribution Md and the visible mass M at radius r, previously demonstrated for spiral galaxies, is extrapolated to the case of a simple cluster core with mass distribution constrained by a lens mass model. In the at present unique case of MS 2…
Ly-α Observation of a Coronal Streamer with UVCS/SOHO
Romoli, M.; Modigliani, A.; Fineschi, S. +3 more
In this paper we discuss some characteristics of an equatorial streamer observed by UVCS in July 1997. We determine the height distribution of the Ly-α total intensity and of its width. We focus our attention, in particular, on the time variability of these parameters.
ISOCAM cosmological Surveys
Aussel, H.; Elbaz, D.; Cesarsky, C. J.
Several deep surveys have been performed at 7 and 15 µm by using the mid-infrared camera ISOCAM on board the ISO satellite. We review their first results, emphasizing on the excess detected in the 15 µm counts with respect to the predictions of models with a mild evolution that is sufficient to explain the IRAS counts. We point out tha…
The optical/near-infrared broad-line emission and hard X-ray continuum of active galactic nuclei and ultraluminous infrared galaxies
Imanishi, Masatoshi; Ueno, Shiro
We compare the luminosities of the hard X-ray and optical/near-infrared broad-line emission from active galactic nuclei (AGNs) and ultraluminous infrared galaxies (ULIRGs). Both types of emission are thought to be good indicators of activity driven by supermassive black holes. We selected objects for which both X-ray and broad-line data are availa…
Determination of 7-30 MeV electron intensities: ULYSSES COSPIN/KET Results
Sierks, H.; Kunow, H.; Muller-Mellin, R. +6 more
The COsmic and Solar Particle INvestigation Kiel Electron Telescope was designed to measure electrons from a few MeV up to a few GeV using particle energy loss and particle velocity measurement techniques. Unfortunately the KET channel measuring electrons in the energy range from 7-170 MeV is contaminated by a γ-ray background (Ferrando et al., 19…
New Measurements of the Solar Limb Emission in the O I 777.4 and 844.6 Nanometer Lines
Penn, M. J.
Slit spectra of the solar limb emission in the 777.4 and 844.6 nm O I lines are calibrated against the solar disk center brightness. Data from CCD spectrograph instruments at two different observatories show limb emission with identical line intensities and measure a value of R4≡ΣI(844.6 nm)/ΣI(777.4 nm)=0.20+/-0.02, very different from…
Science tools on the Internet-access to information, data and models
Bilitza, D.
In just a few years the Internet has become an essential element in national and international science endeavors. Transfer of data, models, and related software across the net has skyrocketed. Interactive WorldWideWeb modules let the users do everything from simply specifying time periods for data retrieval to plotting complex data sets, to comput…
HD 30187 B and HD 39927 B: two suspected nearby hot subdwarfs in resolved binaries
Makarov, Valeri V.; Fabricius, Claus
In doing a B_T, V_T photometric solution for close Hipparcos double stars, based on the observations with the Tycho instrument of the Hipparcos satellite, we discovered two very blue subluminous components of HD 30187 and HD 39927. The position of the components on an observational HR diagram implies their being sdO or sdB hot subdwarfs. The only …
Signatures of Coronal Hole Spectra Between 660 Å and 1460 Å Measured with SUMER on SOHO
Solanki, S. K.; Wilhelm, K.; Curdt, W. +2 more
Spectra of the northern polar coronal hole measured with the SUMER spectrometer on SOHO on 25 October 1996 are analyzed. We present spectra taken at locations on the solar disk where part of the spectrometer slit intersects a polar coronal hole region and an area of brighter emission from outside of the coronal hole area. By comparing the line int…
CCD measurements of visual double stars made with the 50 CM refractor of the Nice Observatory
Gili, R.; Salaman, M.; Morlet, G.
We present the measurements of 49 visual double stars made in 1997 with the 50 cm refractor of the Nice Observatory (Table 1). A CCD camera was attached to this refractor. Some new binaries discovered by Hipparcos have been measured. The algorithm used for these measurements is based on the adjustment of a tridimensional mathematical surface. Tabl…