@book{JRC41167, editor = {}, address = {Luxembourg (Luxembourg)}, year = {2007}, author = {Verbruggen A and Richter S and Kuehn H and Kehoe F and Wellum R}, isbn = {}, abstract = {Some of the longest and most accurate measurements on the half-life of plutonium-241 have been carried out at IRMM. The measurements started in 1976 and were all made on a single sample of highly enriched 241Pu. A double isotopic ratio methods is applied in which n(241Pu)/n(240Pu) is compared with n(240Pu)/n(239Pu) to yield an effective ratio n(241Pu)/n(239Pu). This method is internally highly consistent and repeated measurements on the same solution have yielded the value of 14.29 years [1]. The last measurements were carried out in 1996 and therefore it was considered that this was an appropriate time to carry out another repeat on this solution. Previous measurements were done on a standard thermal ionisation mass-spectrometer (TIMS) using a single Faraday collector in the peak jumping mode. For the present set of measurements a different TIMS was also used in which a completely different analysis type was applied: total evaporation with multi-Faraday collectors. The accumulated set of measurements includes work done using several mass-spectrometers and operators. Great care was taken throughout for each measurement to eliminate 241Am from the plutonium solution before preparing the filaments for mass-spectrometry. An overview of the past and present measurements will be given and the final value from the measurements will be discussed. }, title = {A New Evaluation of the Half-Life of 241Pu}, url = {}, volume = {}, number = {}, journal = {}, pages = {1-6}, issn = {}, publisher = {Office for Official Publications of the European Communities (OPOCE)}, doi = {} }