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This site is the data release accompaniment to the paper entitled:
Narrow-line region gas kinematics of 24,264 optically-selected AGN: the radio connection.
J. R. Mullaney, D. M. Alexander, S. Fine, A. D. Goulding, C. M. Harrison, R. C Hickox
(arXiv: 1305.0263)
In the above paper, we describe the procedure we take to fit the emission line profiles of a large sample of optically-selected AGN from the SDSS DR7 database. By going beyond the single-component fits performed by the standard SDSS pipeline, we are able to more precisely characterise the profiles and fluxes of both forbidden ([O III] and [N II]) and permitted (Ha and Hb) lines, thereby obtaining a better understanding of how the kinematics of the line emitting gas relates to other AGN properties. Furthermore, by precisely characterising the broad component of the permitted lines, we can obtain more precise estimates of AGN properties such as Eddington ratios.
Included in the ALPAKA data table (obtainable via the Downloads page) are parameterisations of our multi-component fits as well as various derived properties such as AGN class (Sy1, Sy2, Narrow-line Sy1), Eddington ratios, Av (i.e., V-band absorption). Descriptions of all the data in the table is provided on the Downloads page.
Please refer to the above paper if you use ALPAKA data in your research.
Example:
The following plot demonstrates the improvement ALPAKA's multi-component fit gives over the single component SDSS fit for a typical Type 1 AGN. Here, by attempting to fit both the narrow and broad component with a single gaussian, the SDSS fit underestimates the width of the Ha line (right hand plot) and fails to characterise the narrow components of the Hb and Ha lines. By contrast, ALPAKA's multi-component fit provides a more accurate representation of the emission line profiles.
Page maintained by James Mullaney
james.r.mullaney@gmail.com
Last updated: 2 May 2013
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