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arXiv · astro-ph/0005165

Discovery of a narrow line Seyfert 1 galaxy

K. P. Singh·L. R. Jones
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Abstract

We have discovered a Narrow-Line Seyfert 1 (NLS1) galaxy and identified it with an ultrasoft X-ray source RX 215319-1514 detected with ROSAT. We present its X-ray and optical spectral characteristics. Its redshift is found to be 0.0778+-0.0002. Its optical spectrum shows fairly strong Fe II emission lines, and its X-ray spectrum has an extremely steep power-law index of Gamma greater/equal 4, making it an extremely interesting example of this class of AGNs. No low-energy absorption or variability is observed. The soft X-ray (0.1-2.0 keV) luminosity is estimated to be 3.4-12.5 times 1e43 erg/s, depending on the spectral model.

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K. P. Singh, L. R. Jones. 2000-05-08. Discovery of a narrow line Seyfert 1 galaxy. https://arxiv.org/abs/astro-ph/0005165

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