Cover -- Half-title -- Series-title -- Title -- Copyright -- Dedication -- Contents -- Preface -- Abbreviations -- 1 Introduction to the Extreme Ultraviolet: first source discoveries -- 1.1 Astrophysical significance of the EUV -- 1.2 The 'unobservable ultraviolet' -- 1.3 Early detectors for the EUV -- 1.3.1 Proportional counters -- 1.3.2 Photomultipliers and channel electron multipliers -- 1.4 Early experiments with sounding rockets -- 1.5 EUV astronomy on the Apollo-Soyuz mission -- 1.6 After Apollo-Soyuz -- 1.7 Sources of EUV sky background -- 1.7.1 Geocoronal background -- 1.7.2 The cosmic EUV background -- 2 The first space observatories -- 2.1 Introduction -- 2.2 EUV emission processes -- 2.2.1 A physical understanding of emission processes -- 2.2.2 Stellar photospheres -- 2.2.3 Stellar coronae -- 2.3 Grazing incidence mirror technology -- 2.4 Applications of grazing incidence technology in space -- 2.5 Detector technology for space missions -- 2.5.1 Position encoding systems for detectors -- 2.5.2 Photocathode materials for MCP detectors -- 2.6 Thin film filters -- 2.7 Selected scientific results from Einstein and EXOSAT -- 2.7.1 Photometry and spectroscopy of white dwarfs -- 2.7.2 Einstein and EXOSAT observations of stellar coronae -- 2.7.2.1 RS CVns: the first class of coronal sources -- 2.7.2.2 Coronal surveys and rotation -- 2.7.2.3 Stellar clusters -- 2.7.2.4 Pre-main sequence stars -- 2.7.2.5 Binary systems -- 2.7.2.6 Stellar flares -- 2.7.2.7 XUV spectroscopy -- 2.7.3 EUV photometric observations of CVs with Einstein and EXOSAT -- 2.8 Far-UV spectroscopy with IUE -- 2.9 EUV and far-UV spectroscopy with Voyager -- 3 Roentgen Satellit: the first EUV sky survey -- 3.1 Introduction -- 3.2 The ROSAT mission -- 3.2.1 The X-ray telescope -- 3.3 The ROSAT Wide Field Camera -- 3.3.1 WFC mirrors -- 3.3.2 MCP detectors for the WFC.

3.3.3 Thin film filters -- 3.3.4 ROSAT sky survey strategy -- 3.4 Highlights from the WFC EUV sky survey -- 3.4.1 A new source at 'first light' -- 3.4.2 First detection of a stellar flare in the EUV -- 3.4.3 Optical, EUV and X-ray oscillations in V471 Tauri -- 3.5 The WFC EUV catalogues and the source population -- 3.5.1 The catalogues -- 3.5.2 Identification of EUV sources -- 3.5.2.1 WFC source names -- 3.6 Properties of the white dwarf population -- 3.6.1 Composition and luminosity of DA white dwarfs in the EUV -- 3.6.2 The nature of the photospheric opacity in DA white dwarfs -- 3.6.3 The mass distribution of the EUV selected sample of white dwarfs -- 3.7 Hidden white dwarfs in binary systems -- 3.8 EUV emission from late-type stars -- 3.8.1 EUV luminosity functions and the nearby stellar sample -- 3.8.2 Kinematic properties of EUV selected active late-type stars -- 3.8.3 Cataclysmic variables -- 3.8.4 EUV emission from active galactic nuclei -- 3.8.5 EUV emission from supernova remnants -- 3.9 The interstellar medium -- 3.9.1 A search for the signature of the diffuse background -- 3.9.2 Structure of the local ISM -- 4 The Extreme Ultraviolet Explorer and ALEXIS sky surveys -- 4.1 The Extreme Ultraviolet Explorer -- 4.1.1 The telescopes -- 4.1.2 The thin film bandpass filters -- 4.1.3 The detectors -- 4.1.4 The overall performance of the EUVE imaging telescopes -- 4.2 The EUVE all-sky survey -- 4.2.1 The Right Angle Program -- 4.2.2 Comparison of the WFC and EUVE sky surveys -- 4.3 Key EUVE survey results -- 4.3.1 Science with the long wavelength filters -- 4.3.2 Hot white dwarfs -- 4.3.3 Observations of the Moon -- 4.3.4 Isolated neutron stars -- 4.3.5 EUV emission from classical novae -- 4.3.6 Activity in late-type stars -- 4.3.7 Extragalactic objects -- 4.3.8 Shadowing of the EUVE background -- 4.4 The ALEXIS mission.

4.4.1 Normal incidence mirror technology for EUV astronomy -- 4.4.2 The ALEXIS scientific payload -- 4.4.3 ALEXIS scientific goals -- 4.4.4 ALEXIS in-orbit loss and recovery -- 4.4.5 Scientific results -- 4.4.5.1 The diffuse EUV background -- 4.4.5.2 The narrow band source survey -- 4.4.5.3 Transient phenomena -- 4.4.5.4 Gamma ray bursts -- 4.4.5.5 Obervations of the Moon -- 5 Spectroscopic instrumentation and analysis techniques -- 5.1 The limitations of photometric techniques -- 5.2 The Extreme Ultraviolet Explorer spectrometer -- 5.3 Spectral analysis techniques -- 5.4 Theoretical spectral models -- 5.4.1 Computation of white dwarf model spectra -- 5.4.2 Plasma codes and emission line analyses -- 5.4.3 The emission measure and its distribution -- 5.4.4 What is needed to analyse EUV spectra? -- 5.4.5 Plasma codes for data analysis -- 5.4.6 Abundance measurements and the FIP effect -- 5.5 EUV spectroscopy with other instruments -- 6 Spectroscopy of stellar sources -- 6.1 Emission from B stars -- 6.2 Canis Majoris -- 6.2.1 Absorption lines in the spectrum of CMa -- 6.2.2 Emission lines -- 6.2.3 The wind and the high energy flux from CMa -- 6.3 Observations of beta CMa -- 6.3.1 Pulsations -- 6.4 Coronal sources - the stellar zoo -- 6.5 Main sequence dwarfs (F-K) -- 6.5.1 Procyon -- 6.5.2 Eridani -- 6.5.3 Alpha Centauri -- 6.5.4 Other solar-like stars -- 6.6 Active systems -- 6.6.1 Capella: a reference point in the analysis of active stars? -- 6.6.2 Coronal element abundances in RS CVn systems -- 6.7 Contact and short period binaries -- 6.8 The effect of stellar activity on EUV spectra -- 6.9 Giants and the Hertzsprung gap -- 6.10 Physical models -- 7 Structure and ionisation of the local interstellar medium -- 7.1 A view of local interstellar space -- 7.2 Spectral observations of the diffuse background.

7.3 Interstellar He II and autoionisation of He in the ISM -- 7.4 Interstellar absorption by hydrogen and helium -- 7.5 Interstellar absorption from lines of heavy elements -- 7.5.1 The helium ionisation fraction along the line-of-sight to GD246 -- 7.6 Measuring interstellar opacity with white dwarf spectra -- 7.6.1 Computation of ionisation fractions from column densities -- 7.6.2 Spectroscopic studies of interstellar absorption -- 8 Spectroscopy of white dwarfs -- 8.1 The importance of EUV spectra of white dwarfs -- 8.2 Measuring effective temperature from EUV continua -- 8.3 Photospheric helium in hot white dwarfs -- 8.3.1 Isolated DA white dwarfs -- 8.3.2 White dwarfs in binaries -- 8.3.3 Comments on the role of He in hot DA white dwarfs -- 8.4 Heavy elements in white dwarf photospheres -- 8.4.1 Limits on heavy element abundances in 'pure H' white dwarfs -- 8.4.2 White dwarfs with intermediate heavy element opacity -- 8.4.3 White dwarfs with extreme heavy element opacities -- 8.4.4 Heavy element stratification -- 8.4.5 The hot H-rich CSPN NGC 1360 -- 8.5 Hydrogen-deficient white dwarfs -- 8.5.1 The temperature range of the GW Vir instability strip -- 8.5.2 The composition and temperature of REJ0503-289 -- 8.5.3 The cool DO white dwarf HD149499B -- 8.5.4 The unique bare stellar core H1504+65 -- 8.6 White dwarfs in binary systems with B star companions -- 9 Cataclysmic variables and related objects -- 9.1 Emission mechanisms in CVs -- 9.2 Spectral modelling -- 9.3 EUVE spectroscopy of magnetic CVs -- 9.4 Non-magnetic CVs -- 9.5 Intermediate polars -- 9.6 Summary -- 10 Extragalactic photometry and spectroscopy -- 10.1 Active galaxies -- 10.2 Extragalactic source variability -- 11 EUV astronomy in the 21st century -- 11.1 Looking back -- 11.2 Limitations -- 11.3 New EUV science -- 11.3.1 A deeper sky survey -- 11.3.2 High resolution EUV spectroscopy.

11.3.3 Photospheric opacity in white dwarf atmospheres -- 11.3.4 Stellar coronae and coronal dynamics -- 11.3.5 Cataclysmic variables and related objects -- 11.3.6 Interstellar medium -- 11.3.7 Requirements for new EUV instrumentation -- 11.4 Advanced instrumentation for EUV astronomy -- 11.4.1 The Joint Plasmadynamic Experiment -- 11.4.2 The Colorado EUV opacity rocket -- 11.5 Concluding remarks -- Appendix. A merged catalogue of Extreme Ultraviolet sources -- References -- Index.