Multi-epochs Spectral Variability Analysis of Broad Absorption Lines in QSO SDSS J142225.03+535901.7

Abstract

Broad absorption lines (BALs) in quasars are among the most compelling observational evidence for the presence of outflows. BALs commonly exhibit spectral variability, and analyzing such variations helps to constrain the physical models of these outflows. Variations in the ionizing continuum from the central engine of quasars are thought to be the primary mechanism driving most BAL variability. If the BAL absorption troughs in a quasar simultaneously vary (either weakening or strengthening) at different velocities in the same direction, it is highly likely that BAL variability is primarily induced by variations in the ionizing continuum. The quasar SDSS (Sloan Digital Sky Survey) J142225.03+535901.7, with 55 epochs of high signal-to-noise spectra, displays BAL variability. There is a significant anticorrelation (Spearman's correlation test, with a non-correlation probability $p$-value less than 0.05) between the equivalent widths of various velocity components of the BAL and the continuum luminosity. There is no significant anticorrelation between the equivalent widths of these components and the spectral index of the continuum, ruling out that the potential negative correlation between equivalent width and continuum luminosity is caused by the vertical motion of dusty gas along the line of sight. Therefore, it can be inferred that the BAL variability in this source is primarily driven by changes in the ionizing continuum.