Catching NGC 4051 in the low state with XMM-Newton
Description
The Narrow Line Seyfert 1 (NLS 1) galaxy NGC 4051 shows unusual low flux states, lasting several months, when the 2-10 keV X-ray spectrum becomes unusually hard (photon index<1) while the spectrum at lower X-ray energies is dominated by a large soft excess. A Chandra TOO of the low state has shown that the soft excess and hard components are variable and well-correlated. The variability of the hard component rules out an origin in a distant reflector. Here we present results from a recent XMM-Newton TOO of NGC4051 in the low state, which allows a much more detailed examination of the nature of the hard and soft spectral components in the low state. We demonstrate that the spectral shape in the low state is consistent with the extrapolation of the spectral pivoting observed at higher fluxes. The XMM-Newton data also reveals the warm absorbing gas in emission, as the drop in the primary continuum flux unmasks prominent emission lines from a range of ion species
Additional details
Identifiers
- DOI
- 10.1016/j.nuclphysbps.2004.04.043;
- arXiv
- arXiv:astro-ph/0309179v2;
- PII
- S0920563204001008;
Publishing Information
- Journal Title
- Nuclear Physics. B, Proceedings Supplements
- Journal Volume
- 132
- Journal Issue
- 1-2
- Journal Page Range
- p. 240-243
- ISSN
- 0920-5632
- CODEN
- NPBSE7
Conference
- Title
- 2. BeppoSAX conference on the restless high-energy universe
- Dates
- 5-9 May 2003
- Place
- Amsterdam (Netherlands)
INIS
- Country of Publication
- Netherlands
- Country of Input or Organization
- International Atomic Energy Agency (IAEA)
- INIS RN
- 36017640
- Subject category
- S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
- Resource subtype / Literary indicator
- Conference
- Descriptors DEI
- ASTROPHYSICS; COSMIC PHOTONS; EXTRAPOLATION; HARD COMPONENT; ION EMISSION; KEV RANGE; SATELLITES; SEYFERT GALAXIES; X-RAY SPECTRA
- Descriptors DEC
- BOSONS; COSMIC RADIATION; ELEMENTARY PARTICLES; EMISSION; ENERGY RANGE; GALAXIES; IONIZING RADIATIONS; MASSLESS PARTICLES; MATHEMATICAL SOLUTIONS; NUMERICAL SOLUTION; PHOTONS; PHYSICS; RADIATIONS; SPECTRA
Optional Information
- Copyright
- Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.