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Spectropolarimetry of FIRST 0840+3633

M. S. Brotherton·Wil van Breugel·Arjun Dey·Robert Antonucci
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Abstract

We present Keck spectropolarimetry of a rare ``Iron Lo-BALQSO,'' FIRST 0840+3633. The continuum is 4% polarized near 2000 angstroms rest-frame, but falls to 2% at longer wavelengths, and maintains a relatively constant position angle of 50 degrees. The emission lines are unpolarized. The polarization increases up to 8% in the low-ionization absorption troughs of Mg II 2800 and Al III 1860. The polarization and its position angle vary in a complicated manner across the metastable Fe II absorption lines, suggesting that more than one mechanism is at work or that the system geometry is complex.

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M. S. Brotherton, Wil van Breugel, Arjun Dey, Robert Antonucci. 1997-05-08. Spectropolarimetry of FIRST 0840+3633. https://arxiv.org/abs/astro-ph/9705053

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