Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-05-10
Astronomy and Astrophysics
Astrophysics
To appear in A & A, 12 pages, latex, 15 figures
Scientific paper
10.1051/0004-6361:20010651
We report the detection of a Broad Absorption Line (BAL) outflow in the spectrum of Tol 1037-2703 with three main BALs at 36000, 25300 and 22300~\kms outflow velocities. Although the overall flow is dominated by high ionization lines like and C IV, the gas of highest velocity shows absorption from Mg I, Mg II and Fe II. Covering factor arguments suggest that the absorbing complexes are physically associated with the QSO and have transverse dimensions smaller than that of the UV continuum emitting region (r<0.1 pc). We show that the C IV absorption at \zabs=2.082 has a covering factor $\sim$ 0.86 and the absorption profile has varied over the last four years. The detection of absorption from excited fine structure levels of C II and Si II in narrow components embedded in the C IV trough reveals large density inhomogeneities. IR pumping is the most likely excitation process. The \zabs=2.139 system is a damped system with log N(H I) ~ 19.7. The weakness of the metal lines together with the high quality of the data make the metallicity measurements particularly reliable. The absolute metallicity is close to solar with [Zn/H]=-0.26. The $\alpha$-chain elements have metallicities consistently solar (respectively +0.05, -0.02, -0.03 and -0.15 for [Mg/H], [Si/H], [P/H] and [S/H]) and iron peak elements are depleted by a factor of about two ([Fe/Zn], [Cr/Zn], [Mn/Zn] and [Ni/Zn] are equal to -0.39, -0.27, -0.49, -0.30). Lines from C I are detected but H$_2$ is absent with a molecular fraction less than 8$\times10^{-6}$. High metallicity and low nitrogen abundance, [N/Zn]=-1.40, favor the idea that metals have been released by massive stars during a starburst of less than 0.5 Gyr of age. (abridged)
Petitjean Patrick
Srianand Raghunathan
No associations
LandOfFree
A near-solar metallicity damped Lyman-alpha system toward the BAL quasar Tol 1037-2703 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 A near-solar metallicity damped Lyman-alpha system toward the BAL quasar Tol 1037-2703, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A near-solar metallicity damped Lyman-alpha system toward the BAL quasar Tol 1037-2703 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-244626