Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-04-29
Astrophys.J. 629 (2005) 115-130
Astronomy and Astrophysics
Astrophysics
18 pages, including 17 figures; accepted for publication in the Astrophysical Journal
Scientific paper
10.1086/431342
We present a new spectrum of the quasar HS1603+3820 taken 1.28 years (0.36 years in the quasar rest frame) after a previous observation with Subaru+HDS. The new spectrum enables us to search for time variability as an identifier of intrinsic narrow absorption lines (NALs). This quasar shows a rich complex of C IV NALs within 60,000 km/s of the emission redshift. Based on covering factor analysis, Misawa et al. found that the C IV NAL system at z_abs= 2.42--2.45 (System A, at a shift velocity of v_sh = 8,300--10,600 km/s relative to the quasar) was intrinsic to the quasar. With our new spectrum, we perform time variability analysis as well as covering factor analysis to separate intrinsic NALs from intervening NALs for 8 C IV systems. Only System A, which was identified as an intrinsic system in the earlier paper by Misawa et al., shows a strong variation in line strength (W_obs ~ 10.4A -> 19.1A). We speculate that a broad absorption line (BAL) could be forming in this quasar. We illustrate the plausibility of this suggestion with the help of a simulation. Under the assumption that a change of ionization state causes the variability, a lower limit can be placed on the electron density (n_e > 3x10^4 cm^-3) and an upper limit on the distance from the continuum source (r < 6 kpc). On the other hand, if the motion of clumpy gas causes the variability (a more likely scenario), the crossing velocity and the distance from the continuum source are estimated to be v_cross > 8,000 km/s and r < 3 pc. In this case, the absorber does not intercept any flux from the broad emission line region, but only flux from the UV continuum source. If we adopt the dynamical model of Murray et al., we can obtain a much more strict constraint on the distance of the gas parcel from the continuum source, r < 0.2 pc.
Charlton Jane C.
Eracleous Michael
Misawa Toru
Tajitsu Akito
No associations
LandOfFree
Time-Variable Complex Metal Absorption Lines in the Quasar HS1603+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 Time-Variable Complex Metal Absorption Lines in the Quasar HS1603+3820, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Time-Variable Complex Metal Absorption Lines in the Quasar HS1603+3820 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-402876