A Reconsideration of Ştefania Mărăcineanu’s Measurements of Polonium-210’s Half-Life: Understanding Her Claim to the Discovery of Artificial Radioactivity

Abstract

I re-examine the raw data of the measurements of the half-life of ²¹⁰Po from the Romanian physicist ?tefania M?r?cineanu’s doctoral thesis, performed at the Institut du Radium, 1921–1923, under the supervision of Marie Curie. The half-life values reported in the thesis show relatively large divergences and a possible dependence on the (metallic) support on which the Po source was deposited. These findings influenced M?r?cineanu’s subsequent independent research, and later compelled her to claim priority for the discovery of artificial radioactivity. The present analysis of these data, performed with the least-squares method, certifies the outstanding accuracy of the experimental measurements by providing values with good agreement between the different series of measurements and an average value that is close to the currently adopted half-life value of this isotope. On the other hand, this analysis changes our perspective by showing that the rudimentary procedure M?r?cineanu used to processing the data introduced errors in her reported values, which favored a poor interpretation of the results.