Search Publications

The star pile in Abell 545

Richtler, T.; West, M. J.; Salinas, R. +2 more

Context: Struble (1988, ApJ, 330, L25) found what appeared to be a cD halo without cD galaxy in the center of the galaxy cluster Abell 545. This remarkable feature has been passed almost unnoticed for nearly twenty years.
Aims: Our goal is to review Struble's claim by providing a first (preliminary) photometric and spectroscopic analysis of th…

Initial mass function effects on the colour evolution of disk galaxies

Samland, M.; Kautsch, S. J.; Westera, P. +2 more

Aims:In this work, we want to find out if the IMF can be determined from colour images, integrated colours, or mass-to-light ratios, especially at high redshift, where galaxies cannot be resolved into individual stars, which would enable us to investigate dependencies of the IMF on cosmological epoch.
Methods: We use chemo-dynamical models to …

The correlation between coronal Doppler shifts and the supergranular network

Peter, H.; Lemaire, P.; Aiouaz, T.

A 12 µm ISOCAM survey of the ESO-Sculptor field. Data reduction and analysis

Seymour, N.; Rocca-Volmerange, B.; de Lapparent, V.

We present a detailed reduction of a mid-infrared 12 µm (LW10 filter) ISOCAM open time observation performed on the ESO-Sculptor Survey field (Arnouts et al. 1997, A&AS, 124, 163). A complete catalogue of 142 sources (120 galaxies and 22 stars), detected with high significance (equivalent to 5σ), is presented above an integrated flux den…

AGN counts at 15µm. XMM observations of the ELAIS-S1-5 sample

Pozzi, F.; Fiore, F.; Gruppioni, C. +7 more

Context: The counts of galaxies and AGN in the mid infra-red (MIR) bands are important instruments for studying their cosmological evolution. However, the classic spectral line ratios techniques can become misleading when trying to properly separate AGN from starbursts or even from apparently normal galaxies.
Aims: We use X-ray band observatio…

RX J0042.3+4115: a stellar mass black hole binary identified in M 31, and other papers

Osborne, J. P.; Barnard, R.; Kolb, U. C.

RBS1423 - a new QSO with relativistic reflection from an ionised disk

Husemann, B.; Krumpe, M.; Lamer, G. +1 more

Aims:We present the analysis and results of a 20 ks XMM-Newton observation of RBS1423.
Methods: X-ray spectral analysis is used to establish a significantly broadened relativistic iron Kα line from a highly ionised disk.
Results: A QSO at z = 2.262 was considered to be the optical counterpart of this ROSAT Bright Survey X-ray source. Based…

Optimized data masks for focussed solar tomography: background and artificial diagnostic experiments

Thompson, M. J.; Hughes, S. J.; Pijpers, F. P.

Context: The use of solar tomography for detecting subsurface features in the Sun is now well established. It customarily proceeds from an analysis of data on the solar surface given weightings in a predetermined geometric (e.g. centre-annulus) configuration.
Aims: We seek to improve these weightings by developing a scheme for choosing optimal…

The reddest ISO-2MASS quasar

Cesarsky, C.; Siebenmorgen, R.; Haas, M. +9 more

Context: While there is growing consensus on the existence of numerous dust-enshrouded red quasars, their discovery and detailed exploration is still an observational challenge. In the course of the near-mid-infrared AGN search combining the 6.7 µm ISOCAM Parallel Survey and 2MASS we have discovered 24 type-1 quasars about a third of which a…

Energization of particles in Saturn's inner magnetosphere: Monte Carlo simulation of stochastic electric field effects

Durand-Manterola, H.; Martínez-Gómez, E.; Pérez, H.

Context: Our knowledge of energetic particles in Saturn's inner magnetosphere is based on observations made during the flybys of Pioneer 11, Voyager 1, Voyager 2, and recently by Cassini. The most important features of the energetic particle population in the inner Saturnian magnetosphere are: 1) the rings and the many large and small satellites i…