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We consider energy budgets and radiative history of 8 fading AGN, identifiedfrom mismatch between the ionizion of very extended (>10 kpc) ionized cloudsand the luminosity of the nucleus viewed directly. All show significant fadingon ~50,000-year timescales. We explore the use of minimum ionizing luminosity Qderived from photoionization balance in the brightest pixels in H-alpha at eachprojected radius. Tests using PG QSOs, and one target with detailedphotoionization modeling, suggest that we can derive useful histories ofindividual AGN; the minimum ionizing luminosity is always an underestimate andsubject to fine structure in the ionized material. These tests suggest that theunderestimation from the upper envelope of Q values is roughly constant for agiven object. These AGN show rapid drops and standstills; the common feature isa rapid drop in the last 20,000 years before our view of the nucleus. E-foldingtimescales are mostly thousands of years, with a few episodes as short as 400.In the limit of largely obscured AGN, we find additional evidence for fading,comparing lower limits from recombination balance and the maximum luminositiesderived from from infrared fluxes. We compare these long-term light curves tosimulations of AGN accretion; the strongest variations on these timespans areseen in models with strong and local feedback. Gemini integral-field opticalspectroscopy shows a very limited role for outflows in these structures. Whilerings and loops of emission are common, their kinematic structure shows some tobe in regular rotation. UGC 7342 exhibits local signatures of outflows <300km/s, largely associated with very diffuse emission. Only in the Teacup AGN dowe see outflow signatures of order 1000 km/s. Clouds around these fading AGNconsist largely of tidal debris being externally illuminated but not displacedby AGN outflows. (Abridged)

Fading AGN Candidates: AGN Histories and Outflow Signatures