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We have shown previously that SOHO/UVCS data allow us to detect active region(AR) outflows at coronal altitudes higher than those reached by otherinstrumentation. These outflows are thought to be a component of the slow solarwind. Our purpose is to study the evolution of the outflows in the intermediatecorona from AR 8100, from the time the AR first forms until it dissolves, afterseveral transits at the solar limb. Data acquired by SOHO/UVCS at the time ofthe AR limb transits, at medium latitudes and at altitudes ranging from 1.5 to2.3 R_sun, were used to infer the physical properties of the outflows throughthe AR evolution. To this end, we applied the Doppler dimming technique to UVCSspectra. These spectra include the H I Lyman alpha line and the O VI doubletlines at 1031.9 and 1037.6 A. Plasma speeds and electron densities of theoutflows were inferred over several rotations of the Sun. AR outflows arepresent in the newly born AR and persist throughout the entire AR life.Moreover, we found two types of outflows at different latitudes, both possiblyoriginating in the same negative polarity area of the AR. We also analyzed thebehavior of the Si XII 520 A line along the UVCS slit in an attempt to revealchanges in the Si abundance when different regions are traversed. Although wefound some evidence for a Si enrichment in the AR outflows, alternativeinterpretations are also plausible. Our results demonstrate that outflows fromARs are detectable in the intermediate corona throughout the whole AR lifetime.This confirms that outflows contribute to the slow wind.

Evolution of active region outflows throughout an active region lifetime