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Joined 2026-09-21 Message
Frédéric Joliot-Curie Created 2026-10-24 Updated 2026-11-05
Frédéric Joliot and Irène Joliot-Curie demonstrated that irradiation can create material that still exhibits radioactivity after the irradiating source is removed. In their 1934 report, aluminium exposed to a polonium source continued to emit Positrons afterward, with an exponentially decreasing count rate. Similar behavior in other light elements showed that irradiation had produced unstable nuclear species. Measuring the subsequent radioactive decay separated this persistent activity from radiation produced only during the incoming-particle collisions.[ref]
Artificial Production of a New Kind of Radio-Element by Frédéric Joliot and Irène Joliot-Curie. 1934 abstract, continued positron emission after removal of the polonium preparation
A physicist.[ref]
https://www.nobelprize.org/prizes/chemistry/1935/joliot-fred/biographical/?print=1. Independent professional biography and identity
Portrait of Frédéric Joliot-Curie
. Studio Harcourt / Wellcome Images, via Wikimedia Commons. Creative Commons Attribution 4.0 International., via Wikimedia Commons. Source.
Irène Joliot-Curie Created 2026-10-18 Updated 2026-11-05
Irène Joliot-Curie and Frédéric Joliot identified induced radioactivity by following the Positrons emitted from irradiated light elements after the source was removed. Their 1934 paper reports continuing activity in aluminium, boron and magnesium, with different decay times. The falling count rate is a readout of unstable products left in the material, connecting controlled irradiation with the creation and measurement of radioactive isotopes.[ref]
Artificial Production of a New Kind of Radio-Element by Frédéric Joliot and Irène Joliot-Curie. 1934 abstract, irradiated aluminium, boron and magnesium and their continuing activity
A physicist.[ref]
https://www.nobelprize.org/prizes/chemistry/1935/joliot-curie/biographical/?print=1. Independent professional biography and identity
Portrait of Irène Joliot-Curie
. Studio Harcourt / Wellcome Collection, via Wikimedia Commons. Public domain in France and the United States according to the actual File page’s PD-France and PD-1996 licensing declarations; attribution retained. Source usage terms, via Wikimedia Commons. Source.