Spectropolarimetry of FIRST Broad Absorption Line Quasars

Details Spectropolarimetry of FIRST Broad Absorption Line Quasars Spectropolarimetry of FIRST Broad Absorption Line Quasars

Oct 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997apj...487l.113b&link_type=abstract

Astrophysical Journal Letters v.487, p.L113

Astronomy and Astrophysics

Astronomy

47

Galaxies: Quasars: Absorption Lines, Galaxies: Quasars: Emission Lines, Galaxies: Quasars: Individual Alphanumeric: First J084044.5+363328, Galaxies: Quasars: Individual Alphanumeric: First J155633.8+351758, Polarization

Scientific paper

We present Keck spectropolarimetry of two rare low-ionization broad absorption line (BAL) quasars (QSOs), FIRST J084044.5+363328 and FIRST J155633.8+351758, that also exhibit narrow absorption lines from metastable excited levels of Fe II ("iron Lo-BALs"). These QSOs were discovered in optical follow-ups to a deep radio survey; FIRST J155633.8+351758 is radio-loud, the first BAL QSO so identified. FIRST J084044.5+363328 is highly polarized and exhibits many features found in other BAL QSOs. The continuum is ~4% polarized near the 2000 A rest frame, falling to ~2% at longer wavelengths, at a position angle of ~50 deg. The emission lines are unpolarized. The polarization rises to ~8% in the low-ionization troughs of Mg II lambda 2800 and Al III lambda 1860. The polarization and its position angle vary in a complicated manner across the metastable Fe II absorption lines, which suggests that more than one mechanism is at work or that the system geometry is complex. FIRST J155633.8+351758 may be the most highly polarized BAL QSO known, and it exhibits other unusual polarization properties compared with those of other highly polarized BAL QSOs. The continuum is ~13% polarized near the 2000 A rest frame, falling to ~7% at longer wavelengths, at a position angle of 153 deg. The emission lines are polarized like the continuum, but in the absorption troughs the polarization drops to zero. Currently available data cannot yet discriminate among the possible lines of sight to BAL QSOs (edge-on, pole-on, or random).

Affiliated with

Also associated with

No associations

Rating

Spectropolarimetry of FIRST Broad Absorption Line Quasars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spectropolarimetry of FIRST Broad Absorption Line Quasars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectropolarimetry of FIRST Broad Absorption Line Quasars will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1769242