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The combination of the SDSS and the Chandra Multiwavelength Project (ChaMP)currently offers the largest and most homogeneously selected sample of nearbygalaxies for investigating the relation between X-ray nuclear emission, nebularline-emission, black hole masses, and properties of the associated stellarpopulations. We present here novel constraints that both X-ray luminosity Lxand X-ray spectral energy distribution bring to the galaxy evolutionarysequence H II -> Seyfert/Transition Object -> LINER -> Passive suggested byoptical data. In particular, we show that both Lx and Gamma, the slope of thepower-law that best fits the 0.5 - 8 keV spectra, are consistent with a cleardecline in the accretion power along the sequence, corresponding to a softeningof their spectra. This implies that, at z ~ 0, or at low luminosity AGN levels,there is an anti-correlation between Gamma and L/Ledd, opposite to the trendexhibited by high z AGN (quasars). The turning point in the Gamma -L/Ledd LLAGN+ quasars relation occurs near Gamma ~ 1.5 and L/Ledd ~ 0.01. Interestingly,this is identical to what stellar mass X-ray binaries exhibit, indicating thatwe have probably found the first empirical evidence for an intrinsic switch inthe accretion mode, from advection-dominated flows to standard (disk/corona)accretion modes in supermassive black hole accretors, similar to what has beenseen and proposed to happen in stellar mass black hole systems. Theanti-correlation we find between Gamma and L/Ledd may instead indicate thatstronger accretion correlates with greater absorption. Therefore the trend forsofter spectra toward more luminous, high redshift, and strongly accretingAGN/quasars could simply be the result of strong selection biases reflected inthe dearth of type 2 quasar detections.

Probing the Balance of AGN and Star-Forming Activity in the Local Universe with ChaMP