Book contents
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- IV X-rays and Accretion Disks
- X-ray Variability in AGN
- Thermal Reprocessing of X-rays in NGC 5548
- New Ginga Observation and Model of NGC 6814 Periodicity
- Power Spectrum Fits to EXOSAT Long Looks
- Dramatic X-ray Spectral Variability of Mkn 841
- Thermal and Non-Thermal Emission from Accretion Disks
- Ultra-Soft X-ray Emission in AGN
- Highly Ionized Gas in Seyfert Galaxies
- EUV Observations of Seyfert 1 Galaxies and Quasars
- 0.1–;20 keV Spectra of 3C 273 and E1821+643
- Iron Lines from Ionized Discs
- Reflection Effects in Realistic Discs
- X-Ray Polarization Properties in the Two-Phase Model for AGN
- X-Ray Reprocessing and UV Continuum in NGC 4151
- Dense Clouds Near the Center of Active Galactic Nuclei
- Accretion Discs in AGN Context: Hints Toward Non-Standard Discs?
- Accretion Disk Instabilities
- Compton-Heated Winds from Accretion Disks
- Determination of a Transonic Solution in a Stationary Accretion Disc
- Black Holes and Accretion Disks
- Testing the “Disc X-ray Reprocessing” in UV-Optical Continuum and Line Emission in NGC 5548
- Accretion Discs in Realistic Potentials
- Test of the Accretion Disc Model and Orientation Indicator
- Orientation Effects in QSO Spectra
- The Luminosity-Colour Distribution of Quasar Accretion Disks
- V Beams, Jets and Blazars
- VI Concluding Talk
0.1–;20 keV Spectra of 3C 273 and E1821+643
from IV - X-rays and Accretion Disks
Published online by Cambridge University Press: 04 August 2010
- Frontmatter
- Contents
- Index of Participants
- Preface
- I Evidence and Implications of Anisotropy in AGN
- II Luminosity Functions and Continuum Energy Distributions
- III The Broad Line Region: Variability and Structure
- IV X-rays and Accretion Disks
- X-ray Variability in AGN
- Thermal Reprocessing of X-rays in NGC 5548
- New Ginga Observation and Model of NGC 6814 Periodicity
- Power Spectrum Fits to EXOSAT Long Looks
- Dramatic X-ray Spectral Variability of Mkn 841
- Thermal and Non-Thermal Emission from Accretion Disks
- Ultra-Soft X-ray Emission in AGN
- Highly Ionized Gas in Seyfert Galaxies
- EUV Observations of Seyfert 1 Galaxies and Quasars
- 0.1–;20 keV Spectra of 3C 273 and E1821+643
- Iron Lines from Ionized Discs
- Reflection Effects in Realistic Discs
- X-Ray Polarization Properties in the Two-Phase Model for AGN
- X-Ray Reprocessing and UV Continuum in NGC 4151
- Dense Clouds Near the Center of Active Galactic Nuclei
- Accretion Discs in AGN Context: Hints Toward Non-Standard Discs?
- Accretion Disk Instabilities
- Compton-Heated Winds from Accretion Disks
- Determination of a Transonic Solution in a Stationary Accretion Disc
- Black Holes and Accretion Disks
- Testing the “Disc X-ray Reprocessing” in UV-Optical Continuum and Line Emission in NGC 5548
- Accretion Discs in Realistic Potentials
- Test of the Accretion Disc Model and Orientation Indicator
- Orientation Effects in QSO Spectra
- The Luminosity-Colour Distribution of Quasar Accretion Disks
- V Beams, Jets and Blazars
- VI Concluding Talk
Summary
The high sensitivity and improved spectral resolution (ΔE/E = 0.4 at 1 keV) of ROSAT has enabled high quality spectra to be obtained in the soft X-ray (0.1−2 keV) band. When added to simultaneous Ginga data, spectra extending up to 20 keV are achieved.
3C273 was observed by ROSAT in a pointed observation in June 1990 and again in December 1990 during the survey, when it was also observed by Ginga. The December observation yielded a 3σ detection in the SI filter of the Wide Field Camera. E1821+643, benefits from being at a high galactic latitude and was observed for a total of 40 days during the ROSAT survey, with an effective exposure time of 9ks. Ginga observed the source during this period. It was also observed serendipitously during the pointed phase in February 1991.
Both sources need a two component model to fit their combined 0.1−20 keV spectrum (see Tables 1 & 2). The spectrum of 3C273 has a significant soft excess which exists below 1.2 keV (source rest frame). This may be adequately parameterised by a 200eV Bremsstrahlung or a power law of α = 3.4, however, a single temperature Blackbody or Raymond-Smith model is not a good fit to the data, neither are elementary disc models.
E1821+643 has a strong, steep soft excess which rises below 0.65 keV (source rest frame) in both ROSAT observations.
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- Information
- The Nature of Compact Objects in Active Galactic NucleiProceedings of the 33rd Herstmonceux Conference, held in Cambridge, July 6-22, 1992, pp. 302 - 303Publisher: Cambridge University PressPrint publication year: 1994