XMM Study of Ultrasoft Narrow-Line Seyfert 1 Galaxies SSC_4

GT We propose to extend Xray studies of ultrasoft narrowline Seyfert 1galaxies (NLS1) by making XMM observations of the most interestingmembers of this class. The broad band, large effective area and highspectral resolution of XMM will allow the best Xray studies of NLS1 todate. We will measure their soft and hard Xray continua, their spectralfeatures and their strong flux and spectral variability.