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Session 5 - High Luminosity AGN.
Display session, Monday, June 10
We have obtained a high signal-to-noise (30 \leq S/N \leq 70) high resolution (FWHM = 20 km s^-1) spectrum of the QSO HS 1700+6416 (z_em = 2.72). In this poster we summarize our analysis of the extragalactic heavy element absorption lines detected in this spectrum. Profile fitting indicates that four of the C IV systems are narrow with b < 8 km s^-1. This implies that T < 50000 K, and therefore these systems are probably photoionized. Photoionization modeling of the Lyman limit system at z_abs = 2.315 indicates that this system has a relatively high metallicity, Z \geq 0.2Z_ødot, but some dust depletion must be invoked to understand the relative metal abundances. Curiously, the complex of C IV absorption lines at 2.432 < z_abs < 2.441 shows the weak line of one C IV absorber aligned to within 10 km s^-1 with the strong line of a different C IV doublet for two pairs of C IV absorbers. This is reminiscent of the ``line-locked'' absorption systems detected in associated and broad absorption line systems, and radiative acceleration may play a role. This is somewhat surprising since this absorption complex is shifted by more than 20000 km s^-1 away from the emission redshift. Finally, we apply photoionization modeling to the associated metal system at z_abs = 2.7125, which shows rather strong N V absorption.
Program listing for Monday