Variability of the Iron K - Emission Line in the Seyfert 1 Galaxy Ngc 3516
نویسندگان
چکیده
We present strong evidence for variability of the flux of the iron Kα emission line in the Seyfert 1 galaxy, NGC 3516. Two ASCA observations, separated by ∼ 1 yr, showed a marked decrease in continuum flux by ∼ 60 per cent. The flux in the broad, iron Kα line decreased by the same factor in this time period, with no evidence for changes in the line profile. The line variability is significant at > 99 per cent confidence and rules out models in which the line is produced in a molecular torus located at > 1 pc from the nucleus. An accretion disk is considerably more likely.
منابع مشابه
Variability of the Iron K - Emission Line in the Seyfert 1 Galaxy Ngc 3516 3
We present strong evidence for variability of the flux of the iron Kα emission line in the Seyfert 1 galaxy, NGC 3516. Two ASCA observations, separated by ∼ 1 yr, showed a marked decrease in continuum flux by ∼ 60 per cent. The flux in the broad, iron Kα line decreased by the same factor in this time period, with no evidence for changes in the line profile. The line variability is significant a...
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