9523318 Clements The differences in the spectral energy distributions (SEDs) of the various types of active galactic nuclei willbe analyzed. The SEDs of AGNS span a large portion of the electromagnetic spectrum. Principal component analysis (PCA) will be performed on the SEDs of a large sample of AGNs of various types. This technique will be used to find the normalized components of a multivariable data set (the SEDs of the AGNs) in this case which give rise to most of the variance in the data set. The completed research will contribute to an understanding of the mechanisms which power the various types of AGNs and, in so doing, will help to determine what relationships exist among them. The SEDs of a larger sample of AGNs will be assembled and the types of data will be examined. In particular, the type of observations (broad band photometry or spectrophotometer) will be considered. Selection effects in the data and methods of controlling them will be explored. Models for the various AGN emission components will be investigated. The PCA's performance in decomposing the SEDs of a sample of AGNs into physically meaningful principal components will be evaluated. Techniques for fitting the observed SEDs with the principal components will also be evaluated. Finally, plans will be made for any additional observations that are deemed necessary.
