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Cited by 351

The DOI matches its Crossref record; 61 of the 61 references it cites were found in a registry or an index.

AN ALTERNATIVE APPROACH TO MEASURING REVERBERATION LAGS IN ACTIVE GALACTIC NUCLEI

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Zu, Ying, Kochanek, C. S., Peterson, Bradley M.·2011·The Astrophysical Journal
DOI 10.1088/0004-637x/735/2/80
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Abstract

Motivated by recent progress in the statistical modeling of quasar variability, we develop a new approach to measuring emission-line reverberation lags to estimate the size of broad-line regions (BLRs) in active galactic nuclei. Assuming that all emission-line light curves are scaled, smoothed, and displaced versions of the continuum, this alternative approach fits the light curves directly using a damped random walk model and aligns them to recover the time lag and its statistical confidence limits. We introduce the mathematical formalism of this approach and demonstrate its ability to cope with some of the problems for traditional methods, such as irregular sampling, correlated errors, and seasonal gaps. We redetermine the lags for 87 emission lines in 31 quasars and reassess the BLR size–luminosity relationship using 60 Hβ lags. We confirm the general results from the traditional cross-correlation methods, with a few exceptions. Our method, however, also supports a broad range of extensions. In particular, it can simultaneously fit multiple lines and continuum light curves which improves the lag estimate for the lines and provides estimates of the error correlations between them. Determining these correlations is of particular importance for interpreting emission-line velocity–delay maps. We can also include parameters for luminosity-dependent lags or line responses. We use this to detect the scaling of the BLR size with continuum luminosity in NGC 5548.

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Metadata

Authors
Zu, Y., Kochanek, C. S., & Peterson, B. M.
Venue
The Astrophysical Journal
Publisher
American Astronomical Society
Published
2011-06-20
Volume
735
Issue
2
Pages
80
ISSN
  • 0004-637X (ISSN-L)
  • 1538-4357
DOI
10.1088/0004-637x/735/2/80
OpenAlex
W2109385927
Cited by
351
References
61
FWCI
9.51
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: AN ALTERNATIVE APPROACH TO MEASURING REVERBERATION LAGS IN ACTIVE GALACTIC NUCLEI. https://app.cochat.ai/papers/10.1088/0004-637x/735/2/80
The paper
Zu, Y., Kochanek, C. S., & Peterson, B. M. (2011). AN ALTERNATIVE APPROACH TO MEASURING REVERBERATION LAGS IN ACTIVE GALACTIC NUCLEI. The Astrophysical Journal. https://doi.org/10.1088/0004-637x/735/2/80

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.