Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-01-23
Astrophys.J.660:152-166,2007
Astronomy and Astrophysics
Astrophysics
29 pages, including 17 figures; accepted for publication in the Astrophysical Journal
Scientific paper
10.1086/513097
We present six new and two previously published high-resolution spectra of the quasar HS 1603+3820 (z_em = 2.542) taken over an interval of 4.2 years (1.2 years in the quasar rest frame). The observations were made with the High-Dispersion Spectrograph on the Subaru telescope and Medium-Resolution Spectrograph on the Hobby-Eberly Telescope. The purpose was to study the narrow absorption lines (NALs). We use time variability as well as coverage fraction analysis to separate intrinsic absorption lines, which are physically related to the quasar, from intervening absorption lines. By fitting models to the line profiles, we derive the parameters of the respective absorbers as a function of time. Only the mini-BAL system at z_abs ~ 2.43 (v_off ~ 9,500 km/s) shows both partial coverage and time variability, although two NAL systems possibly show evidence of partial coverage. We find that all the troughs of the mini-BAL system vary in concert and its total equivalent width variations resemble those of the coverage fraction. However, no other correlations are seen between the variations of different model parameters. Thus, the observed variations cannot be reproduced by a simple change of ionization state nor by motion of a homogeneous parcel of gas across the cylinder of sight. We propose that the observed variations are a result of rapid continuum fluctuations, coupled with coverage fraction fluctuations caused by a clumpy screen of variable optical depth located between the continuum source and the mini-BAL gas. An alternative explanation is that the observed partial coverage signature is the result of scattering of continuum photons around the absorber, thus the equivalent width of the mini-BAL can vary as the intensity of the scattered continuum changes.
Charlton Jane C.
Eracleous Michael
Kashikawa Nobunari
Misawa Toru
No associations
LandOfFree
Results of Monitoring the Dramatically Variable C IV Mini-BAL System in the Quasar HS 1603+3820 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 Results of Monitoring the Dramatically Variable C IV Mini-BAL System in the Quasar HS 1603+3820, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Results of Monitoring the Dramatically Variable C IV Mini-BAL System in the Quasar HS 1603+3820 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-602630