Of Iras The Infrared The Election Seyfert1 Seyfert1.5 Type Galaxy Spectra

It is well known that Active Galactic Nucleus (AGN) plays an important role in galaxy evolution and formation of large scale structure in the Universe. The firmly established relationship between black hole mass and the velocity dispersion of bulge where the black hole resides in is a clue of co-evolution of AGN and its host galaxy. Usingα(60,25) as a good indicator of relative importance of AGN and starburst activities, we first examine the evolutionary relationship between Eddington ratio (L/LEdd) and circumnuclear stellar population in a sample of 25 infrared-selected Seyfert 1 galaxies from Slaon Digital Sky Survey and 50 infrared-selected Seyfert 1.5 galaxies from Wang et al. (2006). By comparing the emission line properties with the infrared colorsα(60,25)and Eddington ratio (L/LEdd), following key results are derived: (1) Our Eigenvector 1 is dominated by the anti-correlation between colorα(60,25) and RFe, and is strongly effected by EW(Hβb), L([OIII])and [OIII]/ Hβn. Basing upon a relatively larger and more complete sample, this result confirms the extension of Eigenvector 1 intoα(60,25) derived in Wang et al (2006) . The correlation between RFe andα(60,25) implies a direct linkage between the Eddington ratio and stellar population after exclude the effect of orientation,. (2) We estimate L/LEdd and black hole mass in terms of the continuum luminosity at wavelength 5100? and FWHM of Hβemission line. No correlatetion between L/LEdd and infrared colorα(60,25) is found in our sample, however. We analyze the origin of discrepancy between the observation and prediction: 1) a deficit in the sample size; 2) a contamination by light of host, and propose an improvement in future studies. This discussion is highly important in future studies focusing on the issue of relation betweenL/LEdd and stellar population.