Correlations between the Variation of the Ionizing Continuum and Broad Absorption Lines in Individual Quasars

Abstract

We discover the significant (significance level of >99%) correlations between the fractional variation of the ionizing continuum and that of the C IV and/or Si IV BALs in each of 21 BAL quasars that have at least five-epoch observations from the Sloan Digital Sky Survey-I/II/III. This result reveals that the fluctuation of the ionizing continuum is the driver of most of these BAL variations. Among them, 17 show negative correlations and the other 4 positive correlations, which agrees with the prediction of photoionization models that absorption line variability response to ionization changes is not monotonic. 8 quasars out of 21 examples have been observed at least 30 times on rest-frame timescales as short as a few days, which reveals that changes in the incident ionizing continuum can cause BAL variability even in such a short period of time. In addition, we find that most of the 21 quasars show larger variation amplitude in Si IV than C IV, which reveals the ubiquity of saturation in these BALs (at least for C IV BALs).

arXiv comment10 pages, 1 figure, accepted for publication in ApJ

References in corpus (22)

• The Sloan Digital Sky Survey: Technical Summary
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
• The Sloan Digital Sky Survey Reverberation Mapping Project: Technical Overview
• Quasar Broad Absorption Line Variability on Multi-Year Time Scales
• Tombaugh 2: The First Open Cluster with a Significant Abundance Spread or Embedded in a Cold Stellar Stream?
• The Ionized Gas and Nuclear Environment in NGC 3783 V. Variability and Modeling of the Intrinsic Ultraviolet Absorption
• The Sloan Digital Sky Survey Reverberation Mapping Project: Rapid CIV Broad Absorption Line Variability
• Evidence for Photoionization Driven Broad Absorption Line Variability
• Variation of ionizing continuum: the main driver of Broad Absorption Line Variability
• Variability in Low Ionization Broad Absorption Line Outflows
• The Sloan Digital Sky Survey Reverberation Mapping Project: Systematic Investigations of Short-Timescale CIV Broad Absorption Line Variability
• Correlation between the variation of the ionizing continuum and broad absorption lines
• Narrow absorption lines with two observations of Sloan Digital Sky Survey
• Quasar broad absorption line variability measurements using reconstructions of un-absorbed spectra
• Evidence for photoionization-driven variability in narrow absorption lines
• Ionization driven intrinsic absorption line variability of BAL quasars in the Stripe 82 region
• The correlated variations of C IV narrow absorption lines and quasar continuum
• Saturation Effect on Photoionization-driven Broad Absorption Line Variability
• Correlation between the ionizing continuum and variable C iv broad absorption line in multi-epoch observations of SDSS J141007.74+541203.3
• Variability of broad absorption lines in a QSO SDSS J022844.09+000217.0 on multi-year timescales

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