The Baldwin effect and black hole accretion: A spectral principal component analysis of a complete quasar sample

@article{Shang2003TheBE,
  title={The Baldwin effect and black hole accretion: A spectral principal component analysis of a complete quasar sample},
  author={Zhaohui Shang and Beverley J. Wills and Edward L. Robinson and Derek Wills and Ari Laor and Bingrong Xie and Juntao Yuan University of Texas at Austin and Technion-Israel Institute of Technology and Rutgers University},
  journal={The Astrophysical Journal},
  year={2003},
  volume={586},
  pages={52-71}
}
We have performed a spectral principal component analysis (SPCA) for an essentially complete sample of 22 low-redshift QSOs with spectral data from Lyto H� . SPCA yields a set of independent principal compo- nent spectra, each of which represents a set of relationships among QSO continuum and line properties. We find three significant principal components, which account for � 78% of the total intrinsic variance. The first component, carrying � 41% of the intrinsic variance, represents Baldwin… Expand
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