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Accurate measurements of the F-center lifetime, z ( T ) , in additively colored NaF: LiF samples are presented as a function of the temperature, starting from 7.6 K. The anomalous behavior of the F-center decay in NaF is confirmed only as regards the behavior of the relative quantum yield ~~( 2 " ): the presence of another decay channel for the F-center electron, besides the jumping into the conduction band, is evidenced. The disagreement with data obtained by other authors is explained by the presence of aggregate centers in their samples. A z(!P)/r],(T) behavior contrary t o that presented by Stiles, Fontana, and Fitchen is observed. A critical review of models and guesses proposed in the literature is also presented in order to obtain a correct understanding of the nature of the relaxed excited state of the F-center.Dans ce travail on pr6sente des mesures accurBes, en fonction de la temperature, de vie moyenne du centre F, pour des Bchantillons de NaF:LiF additivement colorbs, & partir de 7,G K. Le eomportement irrBgulier du centre F in NaF est confirm6 seulement si on considhe le rendement quantique 7lr(T) : d'autre partie on a mis en evidence la pr6sence d u n autre canal de dBsexcitation pour 1'Bleetron du centre F, au deli du ,,jump" dans la bande de conduction. Le dbsaccord trouvB avee les donnBes obtenues par d'autres auteurs est expliqu6 par la presence de centres complexes dans leur Bchantillons. On a observB, egalement, un comportement t( T)/q,(T) contraire B celui present6 par Stiles, Fontnna et Fitchen. On presente, finalement, ime revision critique des modhles et des tentative8 d'interprbtation proposBs dans la litterature dam le but dobtenir une comprehension correcte de la nature de 1'Btat excite relax6 du centre F.