Joliot-Curie, Irène (1897–1956)

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Joliot-Curie, Irène (1897–1956)

French physicist awarded the Nobel Prize for Chemistry, along with her husband, for the discovery of artificial radium, who was appointed a minister of France before the nation's women were allowed to vote and was dedicated to preserving the use of nuclear energy for peaceful purposes. Name variations: Irène or Irene Curie; Irene Joliot-Curie. Pronunciation: ZHol-yo KÜR-ee. Born Irène Curie in Paris, France, on September 12, 1897; died of leukemia on March 17, 1956, in Paris; daughter of Pierre Curie and Marie (Skolodowska) Curie (both famous physicists); sister of Éve Curie (b. 1904); studied at the University of Paris and worked under her mother's supervision at the Radium Institute in Paris; married Frédéric Joliot, on October 9, 1926; children:Hélène Joliot-Curie Langevin and Pierre (both physicists).

Accompanied mother to battlefield X-ray stations during World War I (1914–18); granted Ph.D. with a thesis on the alpha rays of polonium (1925); assumed joint last name with husband at time of marriage (1926); took increasing responsibility for the Radium Institute and became director (1932); awarded the Nobel Prize for Chemistry with her husband for the discovery of artificial radium (1935); as undersecretary of scientific research, one of three women in cabinet of Léon Blum, helped to establish the National Center for Scientific Research (1936); won the Barnard Gold Medal for Meritorious Service to Science,the Henri Wilde Prize, and the Marquet Prize of the Academy of Sciences (1940); driven into hiding in France and Switzerland by husband's active role in the resistance during World War II (1940–45); appointed to the chair of nuclear science at the Sorbonne, previously held by both her father and mother; appointed to the French Atomic Energy Commission (CEA); dismissed with her husband from the cea for communist sympathies and opposition to the use of atomic energy for nuclear weapons (1950); lobbied successfully for a new Institute of Nuclear Physics, constructed in the 1950s; given a state funeral, befitting one of the pre-eminent scientists of France (1956).

On December 10, 1911, the shy, solemn-faced girl of 14 sat in the auditorium of the Royal Academy of Music in Stockholm, watching as her mother received the Nobel Prize for Physics. Irène Joliot-Curie was already accustomed to the world of high intellectual achievement, as well as to personal tragedy and the everyday labors of science. It was the second Nobel awarded to her mother; her father, who had shared in the first, was now dead. In the past year, Irène had also lost the beloved grandfather who had raised her. Against this background, her future was similarly set along a path of hard work, considerable suffering, dedication, and high achievement.

When Irène Curie was born on September 12, 1897, her parents were still relatively unknown. Her father Pierre Curie worked in the laboratory of the School of Physics and Chemistry at the Sorbonne, developing new equipment that would eventually prove essential to all physics laboratories, and her Polish-born mother Marie Curie , who had begun her advanced academic career at age 24, was determinedly pursuing her scientific studies at the same school. The couple had been on a bicycling vacation when it was cut short by Irène's birth; she was delivered by her paternal grandfather, Dr. Eugène Curie. It was a fortuitous beginning to the close relationship that was to develop between the French physician and his granddaughter. Widowed soon after Irène's birth, Eugène eventually moved in with his son's family.

Irène was adored by her mother, who called her "my little Queen" and kept track of her growth and the arrival of new teeth in a school notebook. But Marie Curie was also a dedicated, even driven, scientist. Although the Curies held Ph.D.s, Pierre's position at the Sorbonne did not support the family, so Marie lectured in physics at a suburban girls' school and spent hours in the laboratory doing research. Irène's grandfather became the center of her universe. Even so, she did not go to sleep at night until her mother had been to her bedside.

Irène was six the year her mother received her doctorate and both parents were awarded the Nobel Prize for Physics. Their discovery of two radioactive elements, radium and polonium, made the couple famous throughout the world, and the prize money made the family's life somewhat easier. In December 1904, Irène's sister Éve Curie was born, and the family moved to a larger home. But in April 1906, when Irène was nine, her father Pierre died in a traffic accident.

Despite the loss of her partner, Marie Curie would not accept the offer of a pension. Instead, she accepted her husband's chair in physics and continued her work. The family moved to a house in the Paris suburb of Sceaux where Irène and her mother grew flowers, a shared passion. Her grandfather remained by her side, teaching her botany and natural history; he was "the incomparable friend … of that slow, untamed child so profoundly like the child he had lost," wrote Éve. Grandfather Curie died in 1910, four years after his son.

Educated in their early years by governesses who were usually Polish like their mother, the Curie sisters became fluent in French, Polish, and English and were good students in science and mathematics. Madame Curie had high academic standards, but she also believed that women must be physically fit and required that the girls get daily exercise. They often took walks or performed gymnastics on a garden crossbar with a trapeze and flying rings, and both brought home prizes for their gymnastic achievements. They also learned cooking, sewing, and modeling with clay. Although life in the household revolved around Marie's work, the family spent happy holidays cycling through the countryside or visiting the coast. In 1911, after the second Nobel Prize, the sisters visited their maternal Aunt Bronya in Poland, where they learned to ride horseback and took long mountain hikes.

Like her father, Irène was extremely shy, but her gift for mathematics and science was apparent at an early age. As her daughters outgrew the abilities of their governesses, Marie Curie, dissatisfied with available schools, decided to create her own. She set up a teaching cooperative, staffed by Sorbonne professors for their children, where students learned mathematics, chemistry, physics, and art from some of the best minds of the time and were exposed to such famous scientists as Albert Einstein.

With the outbreak of World War I, Irène thought of being a nurse in order to help with the wounded. When her mother's discovery of radium found practical use in X-ray equipment, Irène was trained to operate the equipment and worked closely with Madame Curie in radiological stations set up near the battlefront. By the end of the war, Irène knew that she wanted to be a physicist like her mother. "The fame and the achievement of her parents neither discouraged nor intimidated her," Éve wrote of her sister.

In May 1921, the sisters accompanied Madame Curie on a triumphal tour of the United States. Because their mother found the trip exhausting, Irène often had to assume her mother's social duties despite her shyness; one photograph from the period shows Irène alongside President Warren Harding at the White House as her mother is presented with a symbolic gram of radium. Back in Paris, creature comforts were of little interest to this mother and daughter, whose lives were dominated by their work at the Radium Institute, founded by Madame Curie. Éve describes a typical lunch in the family's charmless apartment on the Ile St. Louis, in which Marie and Irène sat engrossed in scientific dialogue, oblivious to their surroundings, food, or the clothes they wore.

In 1925, Irène was awarded a doctorate for her thesis on the alpha rays of polonium, the element discovered along with radium by her parents. That same year, she met a shy, handsome young man named Frédéric Joliot, regarded as the most brilliant of her mother's assistants. Frédéric idolized the work of Marie and Pierre Curie and kept their pictures in his home laboratory; with him, Irène found someone who could share her passion for science. Frédéric described Irène as "the living replica of what her father had been," and he shared her love of sports and the arts, as well as a dislike for city life. When they married, on October 9, 1926, both changed their names to Joliot-Curie and worked henceforth as equal partners, signing all their scientific papers jointly, as Pierre and Marie Curie had once done.

Because of the pioneering work of the elder Curies, an exciting world of atomic physics had opened up. Other scientists had subsequently discovered the negatively charged particle called the electron, the components of the nucleus, and the existence of various atomic isotopes. The Joliot-Curies, highly skilled in the use of radiation detectors, turned to the study of the atomic byproducts created when materials like aluminum

or boron are bombarded by alpha particles, identified as positrons. Using an instrument known as the Wilson cloud chamber, they irradiated samples of boron and aluminum and observed the results. To their surprise, the positrons that they had expected to be emitted continued after the polonium source was removed, demonstrating that portions of the aluminum and boron in their exposed samples had been transmuted into elements which were radioactive and short-lived, but also entirely new and unlike any naturally occurring element. The Joliot-Curies went on to produce a large number of these artificially created radioactive elements and announced their discovery on January 15, 1934.

As a result of prolonged exposure to radioactivity, Madame Curie had meanwhile become severely ill with leukemia, and her responsibilities at the Radium Institute had passed to Irène, who became director in 1932. Before her death in July 1934, Marie Curie fully understood the extent of her daughter's achievement in research, and in 1935 Irène and Frédéric Joliot-Curie shared the Nobel Prize for Chemistry "for their synthesis of new radioactive elements." Thanks to their discoveries, wrote J.W. Palmaer of the Royal Swedish Academy of Sciences, "it has become possible, for the first time, to transform artificially one element into another hitherto unknown. The results of [their] researches are of capital importance for pure science."

By this time, the couple were parents of a daughter and son, Hélène and Pierre, who would one day be physicists like their parents and grandparents. While the work of the Joliot-Curies remained intense, the family enjoyed card games, conversation, tennis, and walks with friends.

Like her mother, Irène Joliot-Curie regretted that women did not have the place in society they deserved and found time for women's issues. In 1936, under France's Popular Front government led by Léon Blum, she was appointed the country's undersecretary of state for scientific research, at a time when the women of France had not yet won the right to vote (denied until 1945). In this role, she helped lay the foundations for the National Center for Scientific Research.

Aware of radiation as the cause of Madame Curie's death, the Joliot-Curies were deeply concerned about the potential for great harm as well as good in the use of atomic energy. In his Nobel lecture, Frédéric had summed up their feelings, saying, "We are entitled to think that scientists … will be able to bring about transmutations of an explosive type, true chemical chaining reactions [that liberate vast amounts of usable energy]. But … if the contagion spreads to all the elements of our planet, the consequences of unloosing such a cataclysm can only be viewed with apprehension." In fact, the Joliot-Curies demonstrated fission in their laboratory by physical means as early as 1939. Fearful of the consequences and afraid of the growing power of Adolf Hitler in Germany, they stopped publishing papers on their discoveries.

On May 10, 1940, Hitler's German armies invaded France. Shortly before the Nazi troops rolled into Paris, the Joliot-Curies managed to ship a sample of heavy water, vital to nuclear reaction, to Britain. Frédéric had lied to Gestapo agents to get the material out of their hands. Soon after the occupation, Paul Langevin, a longtime friend of the couple, was arrested. (Their daughter Hélène would later marry his grandson, Michael Langevin.) Frédéric, meanwhile, supported by Irène, joined the French Communist Party, believing that it offered the best organized resistance against Nazi repression. "I was impressed by the generosity, courage, and hope for the future that these people in my country had," he said later. "They seemed willing to do the most to give France social reform." On the front lines of the secret resistance, Frédéric directed the manufacture of explosives and radio equipment for the resistance fighters and allowed the publication of an underground newspaper from his lab. Detection in such activities would have meant certain death at the hands of the German Gestapo, and at one point Irène and the children were forced to flee to Switzerland while Frédéric went into hiding.

After the war, many honors were bestowed on the Joliot-Curies. Both were appointed to the French High Commission on Atomic Energy, which developed French nuclear energy and weapons. Like Marie and Pierre Curie before them, they believed that scientific discoveries were worldwide property, and they wanted the work of French scientists communicated to American and Soviet scientists rather than concealed in the interest of national defense. But the Allied bombings of the Japanese cities of Hiroshima and Nagasaki near the end of the war had also reinforced their conviction that nuclear force should be used only for peaceful purposes. "Its use for destruction seemed to [mother] a desecration," said Irène. "In her eyes any political consideration would not have been an excuse to use the atomic bomb."

As the Cold War intensified, the French government grew increasingly afraid of sharing scientific discoveries with Soviet scientists. Irène meanwhile denounced scientific secrecy for its limitations on the free circulation of ideas and discoveries, and she and her husband made several trips to the Soviet Union in the hope of furthering world peace and international cooperation. They became active members of the World Peace Council, and Frédéric became its president. In the Cold War atmosphere of the West, their outlook became increasingly suspect, and in 1949, when Irène visited the United States, she was detained for a day on Ellis Island. Eventually the couple's political beliefs led to their removal from France's High Commission on Atomic Energy.

Meanwhile, the Joliot-Curies began to be dogged by radiation sickness. Irène was the first to show the symptoms but continued to be active in various world peace organizations and drew up a plan for the new nuclear physics laboratories at Orsay, where scientists could work with large particle accelerators. In 1955, the dream of this research center was realized, but by this time Irène was wasting away. "Breathing, eating, all the most elementary functions, are becoming painful," she told a friend. She died of leukemia in the Curie Hospital in Paris on March 17, 1956, followed two years later by Frédéric, who also died of leukemia. Despite the carping of some in the French government, Irène Joliot-Curie was given a state funeral, an honor befitting her scientific achievements.

Though dedicated to family and the consuming work of her lifelong research, Irène Joliot-Curie also understood that the scientific frontier is not enough. Recognizing that humans must be willing to cross new moral and ethical frontiers, she devoted time and energy to the political rights and opportunities of women, and long before there was widespread understanding of this issue, to the cause of eliminating the threat of nuclear destruction. Like many visionaries, she paid a high price for being decades ahead of the rest of the world.