EXSAS command summary Supplement to EXSAS user's guide

This supplement to the EXSAS user's guide contains: 1. a list of the commands and 2. a detailed description of all the commands (including purpose, syntax and examples). (AKF)Available from TIB Hannover: RA 234:ET(257a) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

EXSAS user's guide Extended Scientific Analysis System to evaluate data from the astronomical X-ray satellite ROSAT

For data evaluation support of ROSAT observers the ROSAT Scientific Data Center (RSDC) at the Max-Planck Institut fuer Extraterrestrische Physik (MPE) in Garching has set up a Standard Processing and Analysis System (SASS) routinely applied to all data and the Extended Scientific Analysis System (EXSAS) for individual interactive data analysis work of the ROSAT observers. Although EXSAS has been developed specifically for data analysis of the ROSAT instruments, its structural design is sufficiently general to serve equally well also data from other X-ray and XUV instruments. EXSAS has been built on top of the well-known and widely accepted ESO-MIDAS environment and is thus available to the many astronomical sites already using MIDAS. (orig./HM)Available from TIB Hannover: RA 234:ET(244) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

EXSAS user's guide Extended scientific analysis system to evaluate data from the astronomical X-ray satellite ROSAT

For data evaluation support of ROSAT observers the ROSAT Scientific Data Center (RSDC) at the Max-Planck Institut fuer Extraterrestrische Physik (MPE) in Garching has set up a Standard Processing and Analysis System (SASS) routinely applied to all data and the Extended Scientific and Analysis System (EXSAS) for individual interactive data analysis work of the ROSAT observers. Although EXSAS has been developed specifically for data analysis of the ROSAT instruments, its structural design is sufficiently general to serve equally well also data from other X-ray and XUV instruments. EXSAS has been built on top of the well-known and widely accepted ESO-MIDAS environment and is thus available to the many astronomical sites already using MIDAS. This edition 4 of the EXSAS User's Manual describes the status of the EXSAS software as released in July 1994. With this release the versatility of the package is enhanced and insufficiencies are corrected. (orig./AKF)Available from TIB Hannover: RA 234:ET(257) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Accretion and magnetism - AM Herculies stars. Polars in the ROSAT era

The accretion processes in Am Herculis binaries are reigned by the strong magnetic field of a mass-accreting white dwarf. In the first part of this article I describe the methods applicable to infer the strength and structure of the magnetic fields in these systems. These are based on direct measurements of Zeeman split Balmer lines and/or harmonic cyclotron emission. All well-studied systems show signs of complex field structures or at least deviations from the most simple model of a centered dipole. The observed range of B-values is 10 -70 MG. The evolution of the systems is responsible for this range being much narrower than that measured in single white dwarfs, 100 kG - 1000 MG (see Schmidt 1995, this volume). The following parts of this article are devoted to other processes intimately interwoven with the presence of magnetic fields. These are the accretion streams (instead of accretion disks), the different ways of energy release in the accretion spots and the synchronous rotation of both stars. Considerable progress was reached in various fields after the launch of ROSAT which detected a lot of new and some very remarkable systems and which made detailed observational studies of individual systems possible. (orig.)Available from TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman