[7] The curriculum of The Cooperative was varied and included not only the principles of science and scientific research but such diverse subjects as Chinese and sculpture and with great emphasis placed on self-expression and play.

[6] Irène re-entered a more orthodox learning environment by going back to high school at the Collège Sévigné in central Paris until 1914.

[7][11] Her doctoral thesis was concerned with the alpha decay of polonium, the element discovered by her parents (along with radium) and named after Marie's country of birth, Poland.

[7] As she neared the end of her doctorate in 1924, Irène Curie was asked to teach the precision laboratory techniques required for radiochemical research to the young chemical engineer Frédéric Joliot, whom she would later wed. From 1928 Joliot-Curie and her husband Frédéric combined their research efforts on the study of atomic nuclei.

[9] Though their experiments identified both the positron and the neutron, they failed to interpret the significance of the results and the discoveries were later claimed by Carl David Anderson and James Chadwick respectively.

The Nobel Prize for chemistry in 1935 brought with it fame and recognition from the scientific community and Joliot-Curie was awarded a professorship at the Faculty of Science.

Lise Meitner and Otto Frisch would theoretically correct Hahn and Strassmann's findings, and after replicating their experiment based on Hungarian physicist Leo Szilard's theory that he had confided to Meitner back in 1933, confirmed on 13 January 1939 that Hahn and Strassmann had indeed observed nuclear fission: the splitting of the nucleus itself, emitting vast amounts of energy.

Lise Meitner's now-famous calculations actually disproved Irène's results and proved that nuclear fission was possible and replicable.

[11][9] The Joliot-Curies were a part of the organization in charge of the project, the Atomic Energy Commission, Commissariat à l'énergie atomique (CEA).

[11] The reactor, Zoé (Zéro énergie Oxyde et Eau lourde) used nuclear fission to generate five kilowatts of power.

Despite this, Joliot-Curie continued to work and in 1955 drew up plans for new physics laboratories at the Orsay Faculty of Sciences, which is now a part of the Paris-Saclay University, south of Paris.

[16][11] They opposed its ideals and joined the Socialist Party in 1934, the Comité de vigilance des intellectuels antifascistes a year later, and in 1936 they actively supported the Republican faction in the Spanish Civil War.

[16] In the same year, Joliot-Curie was appointed Undersecretary of State for Scientific Research by the French government, in which capacity she helped in founding the Centre National de la Recherche Scientifique.

[18] The Joliot-Curies had continued Pierre and Marie's policy of publishing all of their work for the benefit of the global scientific community, but afraid of the danger that might result should it be developed for military use, they stopped: on 30 October 1939, they placed all of their documentation on nuclear fission in the vaults of the French Academy of Sciences, where it remained until 1949.

The Joliot-Curies were given memberships to the French Légion d'honneur; Irène as an officer and Frédéric as a commander, recognising his earlier work for the resistance.

[16] Concern for her own health together with the anguish of her husband's being in the resistance against the German troops and her children in occupied France was hard to bear.

[16] She did make several dangerous visits back to France, enduring detention by German troops at the Swiss border on more than one occasion.

[11] In 1956, after a final convalescent period in the French Alps, Joliot-Curie was admitted to the Curie Hospital in Paris, where she died on 17 March at the age of 58 from leukemia, possibly due to radiation from polonium-210.

Joliot-Curie's son, Pierre Joliot, went on to become a biochemist at the Centre National de la Recherche Scientifique.