X-rays from Hot Subdwarfs

Thanks to the high sensitivity of the instruments on board the XMM-Newton and Chandra satellites, it has become possible to explore the properties of the X-ray emission from hot subdwarfs. The small but growing sample of hot subdwarfs detected in X-rays includes binary systems, in which the X-rays result from wind accretion onto a compact companion (white dwarf or neutron star), as well as isolated sdO stars in which X-rays are probably due to shock instabilities in the wind. X-ray observations of these low mass stars provide information which can be useful also for our understanding of the winds of more luminous and massive early-type stars and can lead to the discovery of particularly interesting binary systems.Comment: Review paper to be published in Advances in Space Research (special issue on "X-ray emission from hot stars and their winds"

X-ray emission from hot subdwarfs with compact companions

We review the X-ray observations of hot subdwarf stars. While no X-ray emission has been detected yet from binaries containing B-type subdwarfs, interesting results have been obtained in the case of the two luminous O-type subdwarfs HD 49798 and BD +37 442. Both of them are members of binary systems in which the X-ray luminosity is powered by accretion onto a compact object: a rapidly spinning (13.2 s) and massive (1.28 M_sun) white dwarf in the case of HD 49798 and most likely a neutron star, spinning at 19.2 s, in the case of BD +37 442. Their study can shed light on the poorly known processes taking place during common envelope evolutionary phases and on the properties of wind mass loss from hot subdwarfs.Comment: To be published in the proceedings of the 40th Liege International Astrophysical Colloquium "Ageing low mass stars: from red giants to white dwarfs

Demonstration of VERT-X Critical Items Product Assurance Plan

This Product Assurance Plan (PAP) describes rules and procedures to be followed to assure the performance and reliability of the critical items of Vert-X

TC/TM DATABASE FOR THE EPIC MOS CAMERA SYSTEM (EMCS)

The purpose of this document is to provide a full description of the TC/TM Database provided to ESA for the Flight Model 2 (FM2) of EPIC MOS Camera System (EMCS), in order to support possible users

EMCS DIAGNOSTIC PROCEDURES

This document reports the Command Procedures to perform the Diagnostic readouts of the EPIC MOS CCDs

TC/TM DATABASE FOR THE EPIC PN CAMERA SYSTEM (EPCS)

The purpose of this document is to provide a full description of the TC/TM Database provided to ESA for the Qualification Model (EQM) of EPIC PN Camera System (EPCS), in order to support possible users. This document will become a section of the EPCS User Manual

Requirements specification for the EPIC MOS Camera System (EMCS)

The purpose of this document is to establish the engineering requirements for the design, development, qualification, and production of the EPIC MOS Camera System (EMCS) for the XMM-Newton X-ray telescope

XMM Flight Operation Procedures (Version 2 and following updates) Change and comments for the EPIC MOS 1&2 instruments

This document summarises all the changes to be implemented in the currently existing XMM Flight Operation Procedures relevant to the EPIC MOS instruments (Issue 2 and following updates up to Delta 2.6)

EMCS USER MANUAL

The purpose of this document is to provide a concise but clear and comprehensive definition of the design, interface and operational characteristics associated with the control of the EPIC MOS Camera System (EMCS) in fligh

EPIC MOS Health & Safety Alarms and Actions

This document summarises all the changes to be performed on: - the Issue 1.1 of ESA “Technical note on Instruments Health & Safety Alarms and Actions (XMM-SAX-VILSPA/1999-0032/TN)”, with reference to the EPIC MOS section - the ESOC Operation Database, with reference to the applicable alarm/warning limit