Blue-shifted Emission and Absorption in BAL Quasars

Quasar outflows, probed through blue-shifted emission and absorption lines in quasar spectra, are among the most direct observational manifestations of AGN feedback and play a key role in regulating the energy and momentum budget of host galaxies. Outflows traced in absorption are sensitive to line-of-sight effects, whereas emission-line outflows provide a volume-averaged view of the global outflowing gas. In this study, we investigate the connection between emission and absorption outflows in broad absorption line (BAL) quasars. We analyse multi-epoch spectra of selected BAL quasars drawn from the Sloan Digital Sky Survey Reverberation Mapping program. The Bayesian AGN Decomposition Analysis for SDSS Spectra (BADASS) is employed for continuum modelling and spectral decomposition to extract emission-line properties, while absorption strengths are measured independently. Our analysis reveals a moderate positive correlation between the blue-shifted emission and absorption components, suggesting that both trace related phases of the same outflowing structure. This correlation points to a clumpy, stratified outflow geometry, in which density and velocity gradients distinguish the volume-averaged emission from the line-of-sight absorption. The emission and absorption features respond to continuum variability in a broadly similar, though not identical, manner. Overall, these results place meaningful constraints on the physical nature and geometry of quasar outflows.