Are all Narrow-Line Seyfert 1s Ultrasoft X-Ray Sources?
Abstract
Narrow-Line Seyfert 1s exhibit extreme optical and X-ray properties thought to reflect high accretion rates (m-dot) onto relatively low-mass black holes. A defining characteristic of NLS1s is an ultrasoft X-ray spectrum. We have identified 150 new NLS1s in the SDSS Early Data Release. 50 are detected in the ROSAT All-Sky Survey and show ultrasoft spectra, but most (2/3) were not detected. Of these, 17 have brightnesses and redshifts comparable to those detected, and should have been detected if they too are ultrasoft. This proposal is to observe 17 undetected NLS1s with ACIS-S to measure their X-ray spectral slopes. Finding NLS1s that are not ultrasoft has important implications for understanding how X-ray emission is related to the AGN accretion process.
- Publication:
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Chandra Proposal
- Pub Date:
- September 2002
- Bibcode:
- 2002cxo..prop.1286P
- Keywords:
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- Chandra Proposal ID #04700707