Polarized Broad H-alpha Emission from the LINER Nucleus of NGC 1052

A. J. Barth; A. V. Filippenko; E. C. Moran

doi:10.1086/311976

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arXiv · astro-ph/9902193

Polarized Broad H-alpha Emission from the LINER Nucleus of NGC 1052

A. J. Barth·A. V. Filippenko·E. C. Moran

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Abstract

Optical spectropolarimetry of the nucleus of the LINER NGC 1052, obtained at the Keck Observatory, reveals a rise in polarization in the wings of the H-alpha line profile. The polarization vector of H-alpha is offset by 67 degrees from the parsec-scale radio axis and by 83 degrees from the kiloparsec-scale radio axis, roughly in accord with expectations for scattering within the opening cone of an obscuring torus. The broad component of H-alpha has FWHM ~ 2100 km/s in total flux and FWHM ~ 5000 km/s in polarized light. Scattering by electrons is the mechanism most likely responsible for this broadening, and we find T_e ~ 10^5 K for the scattering medium, similar to values observed in Seyfert 2 nuclei. This is the first detection of a polarized broad emission line in a LINER, demonstrating that unified models of active galactic nuclei are applicable to at least some LINERs.

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A. J. Barth, A. V. Filippenko, E. C. Moran. 1999-02-12. Polarized Broad H-alpha Emission from the LINER Nucleus of NGC 1052. https://doi.org/10.1086/311976

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