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arXiv · 2608.15663

The reddening of NGC 7469 and evidence for variable extinction

C. Martin Gaskell·Ananya R. Kamath·Emily I. Kwan·Divya G. Subramonian
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Abstract

We estimate the reddening of the broad-line region and continuum of the active galactic nucleus NGC 7469 during the 1996 International AGN Watch multi-wavelength monitoring campaign using seven different reddening indicators. As was found for NGC 5548, these indicators support velocity-integrated broad hydrogen line ratios being close to Case B values. All the indicators point to substantial reddening of E(B-V) = 0.44 +/-0.03 for NGC 7469 during mid-1996. We find evidence for a gradual increase of about 10% in the reddening during the seven weeks of the 1996 campaign. Decades-long optical monitoring before and after the campaign is also consistent with modest changes in the extinction from year to year.

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C. Martin Gaskell, Ananya R. Kamath, Emily I. Kwan, Divya G. Subramonian. 2026-08-16. The reddening of NGC 7469 and evidence for variable extinction. https://arxiv.org/abs/2608.15663

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