Oral History Transcript — Dr. Helene Langevin-Joliot
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Interview with Dr. Helene Langevin-Joliot
Helene Langevin-Joliot; April 13, 2003
ABSTRACT: Educational background; how she became interested in science and parental support; choosing nuclear physics; research of her parents, Irene and Frederic Joliot-Curie, and grandparents, Marie and Pierre Curie; women in science; scientistsí responsibility to society; World War II in France; reaction to the atomic bomb; radiation risks and benefits, family information, including her husband (Michael Langevin, grandson of Paul Langevin) and children, and aunt »ve Curie.
Niroomand-Rad:Today is April 13, 2003. I am Azam Niroomand-Rad, Professor from Georgetown University in Washington D.C. I am a Medical Physicist, a member of American Association of Physicists in Medicine and a member of International Organizations for Medical Physics. I am interviewing Professor Helen Langevin-Joliot, a Nuclear Physicist, a decorated officer de la Legion d ĎHonneur, which is the most prestigious honor from the French Government. Helen is the only daughter of Irene Curie and Frederick Joliot and the granddaughter of Marie Sklodowska-Curie. Professor Helen Langevin-Joliot, it is indeed a great honor and pleasure to conduct this interview with you on behalf of AAPM as the Chair of International Affairs Committee, and on behalf of IOMP as the Vice President, on this Centennial celebration of Marie Curieís first Nobel Prize in 1903. Before starting my questions, I would like to briefly review with you your scientific background to the American audience who may not be familiar with you as a scientist. Please correct me because I had very limited information that I could get from communicating with you. Professor Helen Langevin studied at Ecole de Physics et Chimie, one of Franceís best-known high university level school, operated by the town of Paris. It was indeed at this Ecole that Marie and Pierre Curie achieved the Radium discovery. Helen received her Doctorate degree in nuclear physics in 1956 from College de France studying auto ionization and internal bremsstrahlung phenomena. Then she continued her research at the National Center for Scientific Research (CNRS). She has published many scientific papers and has mentored many Physicists. She has served as the Director of the ďInstitute de physique nucleaireĒ experimental research department at Orsay, which is associated with CNRS, and University of South Paris. She has served as Coordinator of the 200 MeV Synchrocyclotron projects, Chair of the CNRS Committee for Nuclear Physics, and member of Advisory Committee for Science and Technology to the Parliamentary Office of France. Professor Helen Langevin-Joliotís interests has included Beta Gamma Spectroscopy, bremsstrahlung, and parity non-conservation, medium energy nuclear reactions, in particular few nucleon problems, before focusing on highly excited particle or hole states in medium and heavy nuclei, using the synchrocyclotron beams then polarized deuteron beams at Saturn. Analyses of the observed giant neutron hole states have given evidence for important role of single hole coupling with collective vibrations together with statistical and chaotic contributions from the high density complicated nuclear levels. Professor Helen Langevin-Joliotís current interests, since you have retired, are increasing science literacy in the general public, in particular, young adults; encouraging women to pursue scientific careers by discussing the lives of Marie Curie and Irene Joliot-Curie and the many challenges that they have overcome; and also promoting radiation discoveries and their uses for benefits of humanity. Professor Helen Langevin is living in the suburb of Paris, spending several weeks on the north coast of Brittany in summer and in the Alps in winter. Among her hobbies, I would say, are sailing, skiing, and gardening. So this is a very brief review of your past scientific interests, and I would like, with your permission, to ask some specific questions.
Langevin-Joliot:I will do my best to answer your questions. One difficulty is that the scientific organization in France is not the same as in the States. I wish also to complete one of your statements: the Nobel Prize for physics was shared by Henri Becquerel with Pierre and Marie Curie, not Marie Curie alone. Donít forget them.
Niroomand-Rad:Well other scientists who will be the primary audience of these tapes in the future and they would know that Marie Curie and Pierre, your grandparents, and Becquerel actually shared the first Nobel Prize in 1903. And you mentioned that after Pierre died in a street car accident that Marie was able to continue her research, and that led her to her second Nobel Prize, which was in 1911, I believe.
Langevin-Joliot:Yes. It was a Nobel Prize for Chemistry.
Niroomand-Rad:Do you remember at what age you became interested in physics?
Langevin-Joliot:I think I became interested in science in general as a young girl, 13, 14, something like that. I was good at school and good in math. I observed my parents and what they were doing seemed to be interesting. So I am not a typical scientist coming from a typical family. I am a scientist coming from a very special family.
Niroomand-Rad:Which makes it interesting for us because I guess my question is that did your parents actually pushed you toward sciences?
Niroomand-Rad:Or it was purely your choice?
Langevin-Joliot:Not exactly. The family tradition, of the Curies and the Joliot-Curies, led me to think that for a girl as well as for a boy, being dedicated to an interesting work was much more important than to be a rich person. Otherwise, I felt free to follow my own interest for choosing a future job. So my parents never pushed me nor my brother. I liked school work and I would say my mother even prevented me to study too hard. She would say, ďYou spend too much time with that.Ē
Niroomand-Rad:Really? Thatís interesting.
Langevin-Joliot:Better to follow the tradition to have fresh air and sport activities, she insisted it very much that I take time for walking, and doing things that were interesting to my age.
Niroomand-Rad:Sciences or math are obviously a very broad area. Why physics?
Langevin-Joliot:Why physics? It is difficult to say. I have probably more in physics at home than math. As a student in secondary school, I was especially good at math. Your husband remarked yesterday that it is much more interesting for a young person to have a problem in math than in physics, because the way you are generally teaching physics: The student has just to apply some law to perform a rather simple calculation, which is much less interesting than solving a math problem. In fact, I was as interested in the math lessons and the math problems as I was in physic problems, but my parents explained to me that the true interest of physics and chemistry and more generally experimental science cannot be found only in books and problems. I remember my mother bought me some bottles with some chemical products and I took those things to a big crystal growing at home. I also displayed a few other ĎĒexperimentsĒ. At that time, there was not so restrictive laws as nowadays, at least in France, so that buying chemical products or using enough voltage in a set up so that the device operates correctly was not such problems. Now, the young guy has voltage of 1.5 volts to be sure they donít become electrocuted. So, I do not say I perform true experiments, but I understood that it will be a pleasure to continue further in this direction. Physics was very much in the front at the time. It was the field everybody was talking about in science. Itís true that today the same situation occurs especially for biology which takes the first place in student minds.
Niroomand-Rad:And actually, when you were growing up in high school that you became interested. This is like, I would say, in mid 1930s, correct?
Langevin-Joliot:More exactly — after the beginning of the war.
Niroomand-Rad:How was the situation for other female or other women at the same time? Was that acceptable by the society?
Langevin-Joliot:At that time, you have high school for the boys and a high school for the girls. We were not together. However, the programs were the same, the exams were the same, and the French baccalaureate was the same. What was striking was that the best majority of girls in high schools, their mothers had no profession at all. They remained at home and did family work. Over 10 girls, maybe you had one whose mother had a profession. So the comparison between boys and girls was that most girls thought to just do like their mothers. They did not especially try to select something interesting for a future job. For me, I never had the idea that I couldnít have a profession.
Niroomand-Rad:Because it was natural for you?
Langevin-Joliot:Yes. I remember an anecdote during the war. France was occupied and its government was copying some of the German Nazi ideas: The rule for women was, church, kitchen, childrenĒ and nothing else. We were given some lessons about these rules at this high school. At one of them, I got so completely angry that I jumped on my feet, I protested and said itís not like that, girls must work. I gave all of my ideas about that. And when I came back home I was proud. I explained the story to my mother, she approved completely, but suddenly she turned to me and said, ďDo you think that other women have a profession as interesting as mine? It was a surprise for me. I understood that the profession of my mother was really a special one, and I had never thought of that before.
Langevin-Joliot:So she told me women must be able to choose what they want to do, and they may be interested in things that may not be interesting to you. In some cases they may be interested in remaining at home and taking care of their children. Why not?
Niroomand-Rad:Was that a private school or was it a public school?
Langevin-Joliot:It was a public school.
Niroomand-Rad:So it was the same for everyone basically?
Langevin-Joliot:Yes, it was the situation during the occupation time.
Niroomand-Rad:So this is basically at the beginning of the forties because of the German occupation. Actually, because of the situation in the sciences and the working and the professional aspects, the women were not encouraged while all men were working. And yet, this is after the time that your mother, Irene, received her Nobel Prize. Isnít this true?
Niroomand-Rad:So itís very interesting to me, at the school the teacher knew that you are the daughter of parents who are highly achieved scientists, and still they were saying that you have to do this and that, so that you had to protest.
Langevin-Joliot:Yes, they were most probably not convinced, but it was the program, so they have to say something of this kind. I would be unable to explain and to reproduce exactly what they said. Maybe I was too much sensitive about the subject.
Langevin-Joliot:Yes, because at first I was suspicious. Maybe I feared that what they were saying may happen to me? Fortunately it happened at the end of the war and with the liberation everything changed and those things were finished.
Niroomand-Rad:What about nuclear physics? At what age/time in your life you became more interested in nuclear physics?
Langevin-Joliot:In fact, I choose to prepare for this School of Physics and Chemistry. At this time, this school prepared people either for research, in general at the University, or to become engineers. So it was a school where you spend the most or half of the time in labs. Not very well equipped at that time. I remember one time we tried to build a mass spectrometer. We did not know very well how to do that and in addition we lacked number of things just after the war. We had no real means to do it. It was — maybe it was asking too much of the student. At the end of the effort, we were not successful to correctly build and to operate the mass spectrometer. We missed one thing, two things, three things. But we learned practically a number of useful procedure and other things. After that, the question was to find a position. Many people were speaking about nuclear physics, sometimes because of the bomb but mainly because the nucleus after many discoveries remains fascinating. It was a newer research field than for example optics. Many people thought that optics was an old thing, which will never interest people in the future. It is easy now to see how stupid this kind of statement was! Because a few years after, most important results leading later to the laser were reached. It seemed especially interesting to investigate the nucleus, why turning to study much more complicated objects, condensed matters for example? Stupid reasoning like these ones happen also today, often. Some of the things many people are talking about now, that seems to be the thing to do now, are not the only interesting ones. There are a number of other problems which may be the starting point of discoveries in fields which are not considered to be so important now. The question of choosing a research field is really difficult for the student. How can they know?
Niroomand-Rad:So if a young adult comes to you and asks you what should I study or why should I choose physics (we are talking more than 30 years down the road), what would be your advice to them?
Langevin-Joliot:When this happens, I am very careful, because of a feeling I have of the story of the last 50 years and the changing of the focus on different points. So, I would say, if you are at the beginning, completely convinced that this kind of physics is very interesting for you, choose it. Even if it is not the one everybody is speaking about, first. Second, if you donít really know, donít only look at papers describing the research, but try to visit labs and to see how people work for their research, the way they are working. You may find big difference with your expectation. Discussing of particle physics, for example, in general terms of theoretical descriptions is quite stimulating. You say that is the thing I want to do. After that, you look what really the experimental particle physicists have to do to go farther. Itís not always exactly what the student would have thought. I try to explain those things. In addition, about the fields people spoke most. I tell the student to take care that at the same moment a large number of students may choose exactly the same thing, which may not be the best way for you. If you really want to do it, do it. Okay. But if you hesitate, it is better to choose something, which is not the one that most students will choose.
Niroomand-Rad:I agree. I guess we all do physics because of the love of physics.
Langevin-Joliot:Yes, but the love of physics is the love of the idea of physics, and it must also be the love of doing physics, and that is not the same.
Langevin-Joliot:And for your life, for the love of doing physics, if you are a teacher, different — you have to explain. If you are more of a researcher, the way you can do physics now is the most important thing.
Niroomand-Rad:Did you capture Melanieís questions? Note to the readers: Melanie was present during this interview on behalf of Dr. Cynthia Keppel, from National Nuclear Physics at Jefferson Laboratory in Newport News, Virginia.
Michael Skinner (The Videographer):We did not. We got part of it, but part of it was not captured. So if you would like to repeat it.
Niroomand-Rad:Melanie, as I understand from your question that when Professor Helen was trying to get her baccalaureate, she had to leave her country?
Langevin-Joliot:Yes, it was in 1944.
Langevin-Joliot:I was prepared to take my second part of the baccalaureate in June 1944. Remember that June Ď44 in France was a very important month. But it happened before that the situation became very dangerous for our family, as my father was a resistant. It was decided that he would remain hidden in Paris but that my mother my brother and I would leave to Switzerland. So we left Paris to a small village Le Russey near the frontier. Before that, my mother had successfully transferred my baccalaureate inscription to Montbeliard, a town rather near to the Swiss border. In fact this town was bombed, and the baccalaureate was shifted to a smaller town. I left Le Russey for three days to take my exam and I came back to my mother on the 5th of June, and the 6th we left to Switzerland. Just that day.
Niroomand-Rad:Before the bombardment?
Langevin-Joliot:No, 6th of June is the day of the allies landed in Normandy, and it was very hopeful for us. First we were very happy, but second it was a good day to pass the border as the German soldiers had something else to do than to search for us. So it was not difficult to escape from France.
Niroomand-Rad:Was the situation the same for your brother?
Langevin-Joliot:My brother was younger.
Niroomand-Rad:How many years?
Langevin-Joliot:He is four and a half years younger than me. So he was a child at the high school at that time.
Niroomand-Rad:So he did not have to come with you?
Langevin-Joliot:He had no reason to come with me for taking my exam. He remained with my mother. I came back from the exam just in time, and the three of us cross the border together. It would have been a problem if I had come back one day later.
Niroomand-Rad:Was your brother also interested in sciences?
Langevin-Joliot:Yes he was, but I would say not the same way. In the family, the girl was good student working, and the boy was more indifferent and did not care to work so much at school. In spite of that, he became a very well good and known scientist. More than me.
Niroomand-Rad:In what field?
Langevin-Joliot:In Biophysics. He works on Photosynthesis. In fact, cellular bioenergetics.
Niroomand-Rad:Do you remember the time that your parents, Irene and Frederic, received the Nobel Prize?
Langevin-Joliot:Yes, I remember that slightly. It was a time we shifted from living in Paris in an apartment there to a new house built for them in the suburb. In fact, they received this telegram at home, and I have a slight feeling of this telegram and my parents saying: Well we have won the Nobel Prize, but this did not mean so much for me.
Niroomand-Rad:How old were you?
Langevin-Joliot:I was eight
Langevin-Joliot:Yes, eight. Yes, then photographers came.
Niroomand-Rad:You said your grandparents were not living at the time when your parents received their award. However, Marie Curie knew by the time before her death that Irene and Frederic had indeed made a huge discovery.
Langevin-Joliot:Yes, because the discovery of artificial radioactivity took place in January1934, and Marie died in July after. My father used to say that this discovery was the last joy of her life.
Niroomand-Rad:Must be really hard. It is really nice. I see these pictures of Marie and Irene working together.
Langevin-Joliot:Yes, that was before, in the Ď20s. In the beginning of the Ď20s.
Niroomand-Rad:Did you also get a chance to do research with your mother?
Langevin-Joliot:Yes, but only during a few months. I was usually working in a room at the College de France located on an underground floor. And the air extracted from the cyclotron hall arrived just in front of the only small window below. Physicians said it was not good for a young person waiting for a baby to spend her days there. I was told to stop that and my mother proposed me to work with her at the Radium Institute instead of remaining there at the Nuclear Chemistry lab of the College de France where the cyclotron was operated.
Niroomand-Rad:Is this place at Radium Institute?
Langevin-Joliot:College de France is a very prestigious institution, parallel to Universities: Professor at the College de France is a position that is considered to be higher level than a professor position at the University.
Niroomand-Rad:You were at the college?
Langevin-Joliot:And that was the place where the cyclotron was.
Niroomand-Rad:That is where Irene and Frederic discovered artificial radioactivity?
Langevin-Joliot:No, Irene and Frederic discovered artificial radioactivity at the Radium Institute.
Niroomand-Rad:At the same place that Marie and Pierre?
Langevin-Joliot:No, Marie and Pierre discovered Radium at the school for physics and chemistry, which is not far from it. Maybe five minutes walking.
Niroomand-Rad:That's where you graduated?
Langevin-Joliot:Okay, and then later Marie obtained that the University together with the Pasteur Institute decided to create the Radium Institute — a laboratory large enough for developing radioactivity researches. That was in 1912. So the Radium Institute had two departments, one part for physics and chemistry directed by Marie Curie, and one part for biology and medicine. During the Great War my mother helped Marie to develop X-ray equipped cars for the wounded. But the discovery of Radium did not happened there. My parents worked at the Radium Institute for their research. After the discovery of artificial radioactivity and the Nobel Prize, the question was to go farther and everybody were convinced that accelerators were needed for that purpose. They decided that my father would create another lab for that and my mother would remain at the Radium Institute. They continued discussing a lot together on physics, but they worked no more together. There were so many things to investigate! Each of them organized a new team with young collaborators. My father became a professor at the College de France and started to build a cyclotron. It was a turning point between the previous way of inducing nuclear reactions with the alpha particle emitted by natural radioelement (Polonium was the best choice), to inducing them with particle beams produced by accelerators. In the United States E. Lawrence had discovered the cyclotron, and he had developed it for several years already, so it was really the time to do that also in France.
Niroomand-Rad:To get to higher energy?
Langevin-Joliot:Yes. And my father was very much interested by the possible applications of radioisotopes to biology and medicine. He really wanted to produce enough quantity of radioisotopes for that. Why is that important? During that time, my mother was working with neutrons.
Niroomand-Rad:With neutron? So she continued her research in neutron bombardment.
Langevin-Joliot:Yes. To tell the truth, after fission was discovered by Hahn and Strassmann — sometimes my parents have commented: Maybe if we had worked together, we would have solved the puzzle and discover uranium fission. My mother came very near to it with Savitch. We cannot know anyway.
Melanie:May I interrupt at this point? I will ask Azam a question, she will then ask you the same question. You answer her. So with the Nobel Prizes, I believe Irene and Fred came very close to discovering the neutron, but didnít know what it was. So they just missed out on that one. They discovered the positron, didnít know what that was and missed out on that one. Thereís not a Nobel Prize there. And then they hit the jackpot with nuclear fission. So could you ask how the parents felt about coming so close to winning so many Nobel Prizes?
Niroomand-Rad:Yes. Melanie raises a very interesting question. At that time, it seems that your parents discovered basically "neutron" but they didnít know what it was.
Langevin-Joliot:Yes, it is exactly that. In fact, they made a key experiment showing that a mysterious radiation, previously discovered by Bothe and Becker in Germany, was able to project out protons from hydrogenous matters, and they published that very quickly and it was a very important step to the neutron. But they continued to suppose, as Bothe and Becker had assumed, that the radiation was gamma rays, very, very energetic gamma rays. In previous discussions between physicists and also people interested in radioactivities and the people interested in cosmic rays, there were a number of puzzling questions. Nobody understood completely the behavior of high-energy gamma rays in matter, because they knew nothing at that time about the production of positive and negative electron pairs (or even the existence of positive electrons).
Langevin-Joliot:My parents published their experiment results with the gamma hypothesis, in spite of the fact that with this hypothesis energy was not conserved. When you look at that nowadays, you must remember that a few months before the most well known theoretician Niels Bohr had suggested energy non conservation may be considered in special nuclear phenomena, such beta ray emission. My parents continued their investigation after publishing their results. But the paper, unfortunately for them, arrived to Chadwick within the week, and Chadwick spent only a few weeks to solve the problem at the Cavendish Laboratory. In that same lab, Rutherford had suggested ten years earlier at the occasion of the Bakerian lecture, that a neutral particle, built with a proton very tightly bound with an electron, (much more tightly bound than in the hydrogen atom) may exist. This idea was not completely forgotten in the Cavendish Lab. So picking that hypothesis, Chadwick set up a beautiful experiment that proved that indeed the mysterious radiation was a neutron, not gamma rays. But what is interesting is also the conclusion of Chadwickís paper announcing the discovery in Nature (a one page or one page and a half long paper only!). The conclusion is something like that; ďAll my experiments say it is a neutron particle, but...the properties of such a neutral particle are difficult to separate from those of high-energy gamma rays. If it would turned to be finally gamma rays, energy non conservation would have to be explainedÖĒ. This ďmay beĒ after the strong conclusion is interesting. The neutron discovery was indeed very soon confirmed. Nowadays, we know the story and it is difficult to imagine the problems physicists were facing.
Niroomand-Rad:Yes, now we know.
Langevin-Joliot:Yes. The point in Chadwickís paper is interesting for historians.
Niroomand-Rad:Itís very interesting. It must have been a very exciting period for the scientists.
Langevin-Joliot:Oh yes there was a series of discoveries.
Niroomand-Rad:Embark on all these discoveries.
Langevin-Joliot:The situation was: I donít understand how the nucleus can be made, and I donít understand what happen to some of the gamma rays, I donít understand what happens with the beta rays which are not emitted in single energy lines but in continuous spectraÖ
Niroomand-Rad:And to me it must be very interesting. I mean, Marie Curie was really the first person who understood, whom actually — you have seen the Journal of Science and Technology for this issue and talk about.
Langevin-Joliot:I have seen the cover, but have not seen inside.
Niroomand-Rad:You havenít seen the article, but it is interesting because of the Centennial and they have written an article about Marie Curie, and they say the woman who opened the nuclear age.
Niroomand-Rad:She was the first person.
Langevin-Joliot:I would say she was not alone to open the door. Donít say that. Itís too much. In spite of the discovery of radium and the fact that she focused on the fact that Becquerelís spontaneous radiation was an atomic property.
Niroomand-Rad:Exactly. That particular understanding, she was the first one to understand that this radiation is coming...
Langevin-Joliot:Yes. If you discuss the data of the story, Becquerel was very much hesitating on the conclusion of some of his experiments, which already indicated that it was an atomic phenomenon.
Langevin-Joliot:The focus was not. So this was one of the reasons for Becquerel to turn to another subject.
Niroomand-Rad:That they shared.
Langevin-Joliot:When you focus on the main problem, the result is not the same as if you just mention it among a lot of other considerations. That often happened in physics. Your idea is more or less inside others, inside previous papers, and the one that makes the breakthrough finally is the one who focuses on the right point.
Niroomand-Rad:As a medical physicist I think what is interesting is that both Pierre and Marie recognized the biological effect of this radiation very early on.
Langevin-Joliot:Yes, they were not strictly the first. Giesel in Germany was the first, to my knowledge. I donít remember if it was a specific experiment, but he had observed the fact of the effect of radiation on the skin. So when Becquerel and Pierre released the paper in 1901, it was their early paper, you could not say that in Germany they did not know about this. The work of Pierre and Becquerel especially in France was very important.
Niroomand-Rad:And also for us in the United States. They used radium forÖ
Langevin-Joliot:Well, in fact Pierre and Marie Curie had given all necessary explanations to a guy (I donít remember his name) in the States who asked how to produce radium. Curie gave all the information to that American guy who developed the production in the States. So that may be one or two connections.
Niroomand-Rad:Later on when you go from the natural radioactivity to the artificial radioactivity, you said that your father was pushing for the synchrocyclotron.
Langevin-Joliot:For the cyclotron.
Niroomand-Rad:For the cyclotron. For the isotopesÖ
Langevin-Joliot:He emphasized the cyclotron ( and high voltage accelerators) as the only efficient way to produce large quantities of radioisotopes. The quantities are much larger than with natural alpha rays or using neutrons produced by a radium beryllium sources (which also allow to get radioisotopes at that time). Hahn and Strassmann and others use radium beryllium neutron sources for research.
Niroomand-Rad:So his interest was primarily from the research prospective, or was it for use in medicine?
Langevin-Joliot:You mean the fact to develop the cyclotron? I would say both, because he created at that time the Laboratory for Atomic Synthesis, and in this lab there was a small part for physics, a small part for chemistry, a small part for biology, so it was not at the College de France. In parallel they developed the cyclotron at the College de France. At the College de France, it was the idea of performing nuclear physics experiments, but also to collaborate with biologists or physicians. I was very much surprised when I checked some papers in the archives. I found that the end of 1938, before fission was discovered, my father was working with a physician and a chemist on thyroid hormone using a bromine radioactive isotope. Then less than two months later, Hahn and Strassmann released their paper announcing their discovery of fission. The next week my father stopped biology experiments and he started working on uranium fission and possible chain reactions.
Niroomand-Rad:So they missed another Nobel Prize?
Langevin-Joliot:The question was now to find if neutrons were emitted by the fission process, so that it would be possible to develop a chain reaction. The shifting from working with physician probably takes less than one month.
Niroomand-Rad:Another question which is interesting to me is when I was growing up, obviously, Marie Curie was role model for a young woman and I learned that she was not permitted to deliver her research at the Academy of Science.
Langevin-Joliot:Itís not exactly that.
Niroomand-Rad:So what is the story there?
Langevin-Joliot:No. The story. Deliver the research is to present a paper. At the Academy of Science, only academicians could present papers, on their own works or on works performed by others, you see. For example, when I was a researcher I wrote a paper and I give it to an academician to present it. So the problem with Marie and with woman and the French Academy was that after Pierre Curieís death, some of her friends and colleagues suggested that she enter the competition to be a member of the French Academy, and that she lost the competition. Another physicist was chosen instead. She was not accepted by the French Academy as a member.
Niroomand-Rad:Because she was a woman?
Langevin-Joliot:There was a huge discussion among all academicians of science and also the academician of the other specialties, liberal arts, literature, to decide if women can be accepted. The conclusion was that each Academy will be free to decide. So in principle, the Frenchís Academy of Science decided that a woman can ask for, and she was in competition with others, and she had not the necessary number of positive votes. The academician preferred to choose a male physicist. After that, Marie never tried because she didnít want to do that. And later this happened with my mother and she was not accepted, but she found that very amusing (this was in the fifties when this happened). So she said okay, each time there is a possibility I will apply. She applied three times without success. And she died.
Niroomand-Rad:So, itís very interesting. At the beginning of the century when Marie got a Nobel Prize, she was not admitted into the Academy. She was a woman. And then they opened up the Academy to women, and then you had to apply to it to be chosen. She wasnít chosen because the other male physicists were more qualified. Then the Academy never appointed or accepted any female scientist. And here comes your mother with another Nobel Prize, applies for the Academy three times, and she still, to her death, was not admitted to the Academy. Now comes the third generation, yourself. Did you apply?
Langevin-Joliot:No. The fact is there are now women at the French Academy of Science. Not a large number, unfortunately, but a few women.
Niroomand-Rad:So when was the first time?
Langevin-Joliot:The first one was elected, if I am right, in 1965 or 1966 or something like that. It was Marguerite Perey who discovered Francium at the Radium Institute under the direction of my mother.
Niroomand-Rad:Under the direction of your mother? So that means your mother died in 1958?
Langevin-Joliot:She died in 1956 and my father in 1958.
Niroomand-Rad:So your motherís student ten years after was able to become the first woman to become a member. So this trouble that they had to go several generations, at least a couple of generations, not mentioning the generations before Curie.
Langevin-Joliot:This generation is far from being perfect. I donít think itís a very specific problem. You are in the same situation now when you look at the situation at the University. If you look at the number of researcher as the lower level you find there sometime a large number of women. If you look at how many of them become a Professor, the number is much lower.
Niroomand-Rad:Which is very true.
Langevin-Joliot:So this is likely improving, but rather slightly.
Niroomand-Rad:Which is true. This was not unique to France. Actually France was more advanced than say other countries in Europe, and even more progressive than the U.S. at the time that these advancements in the sciences were happening.
Langevin-Joliot:I think the difference is more in the number of women working in the scientific field that and the number of women in the highest positions.
Niroomand-Rad:So how do you think the situation is now in France for the women today? In the states we have what is called ďglass ceilingĒ that means exactly what you have said — you have a lot of scientists in the entry level.
Langevin-Joliot:I would say the situation is recognized that for women there is this problem. But in my opinion, nothing is ever completely solved and the situation remains to improve. And the way research developed it was so important. Not only the fact to take care of women, but I would say to take care of the fact that scientists have also to be able to behave as ordinary people with not completely unordinary lives. I think about a few remarks by Pierre Curie, written in a small personal notebook when he was young, may be 18 years old, which are amusing because he was young. His opinions about women were not very good. ďFull of genius women was rareĒ. And also, say in ordinary life, women tried to pick up from work for thinking. And ďwomen love life for the living of itĒ, not for — You see, behind there was an idea we love life to achieve and to be the first. Women love life for the good living — to have a good life to be happy with life. I feel that itís not impossible that as women we have the feelings thatís okay, we have also to have a happy life is that have everybody around us be happy. So, in my opinion it is necessary to have research and to take care of the human aspect as well, and this is good for women and for men.
Niroomand-Rad:To do both?
Langevin-Joliot:To do both. Not to say okay, if you decide to be a researcher you forget everything. All other things are unimportant if you have to be successful. That, in my opinion, is not a good idea. With that idea, I am sure that the ceiling cannot be broken. It can be broken, but artificially. Choosing women just to put them there, and that is not good. Not good at all. To choose women because they are women. That I donít like at all.
Niroomand-Rad:I agree with you. Sometimes you see these ďtoken womenĒ we call it, in some of the government or organizations. I agree with you, thatís not the right approach. You want to make sure that men and women achieve to their potential.
Langevin-Joliot:Yes, but I mean all their potential, not only their scientific potential. Their potentials for life and for connection with others, and for the responsibility of scientists to the citizens and of all that. I feel that for the century, which is beginning, and for young people it is very important. If you wish that young people, boys and girls are interested in science, in the kind of working of science, maybe for a few of them nothing else exist. Why not? But science is too important, and something that many people have to be asked to. If you are thinking that the problem is large number of people, you have to change your mind now, and moreover in the future.
Niroomand-Rad:Actually, the scientist cannot just close the door and put themselves out..
Langevin-Joliot:And it takes time not to close the door. That takes time. So that time you cannot be just only the person of research.
Niroomand-Rad:The more scientists are in touch with the society, the more they can interact with each other and prevent some ill use of the technology.
Langevin-Joliot:Yes, but this takes time.
Niroomand-Rad:For instance, atomic bomb.
Langevin-Joliot:That is the problem. Okay physicists made bomb. It is the fact that scientists contributed to it. You cannot anticipate what they do with science. I mean, saying to the scientist, — donít study nuclear physics because of it may be dangerous, and donít study that part of biology, because this may be dangerous. This is not the way to stop the danger. But on the other way, it is not right to say, ďOkay, I donít care.Ē After the research is known, you have really to care, and itís not so easy.
Niroomand-Rad:So your parents actually saw the first atomic bomb?
Niroomand-Rad:What were their feelings? What were their reactions?
Langevin-Joliot:The first reaction immediately after Hiroshima was not as clear as one or two years after. Just because the war was such and the number of people killed such everywhere. In fact, it was the power of the bomb, which was impressive, not the fact that so many people got killed. Because the burning of Tokyo and the bombing of Hiroshima, killed approximately the same number of people. So the first reaction was that this is powerful, very powerful. And as soon as you as a scientist look into the future and you know what happened on one side, and you anticipate what may happen if the arm race starts, so my parents were very much concerned with the fact to tried to ponder an agreement about forbidding the atomic bomb.
Niroomand-Rad:So they were involved with that?
Langevin-Joliot:Very, very involved with that.
Niroomand-Rad:How old were you at that time?
Langevin-Joliot:I was around 25.
Niroomand-Rad:So you very well rememberÖ
Langevin-Joliot:Oh yes, and I was involved in it also. But unfortunately, the Cold War started nearly soon after, so they were involved in that at the same time. It is true that the problem of the atomic bomb was one of the essential parts of the discussion that started the Cold War. You see, there is a book by Patrick Blackett, an English Nobel Prize winner, a very good physicist doing a lot of research work and having also participated to wartime work, about the consequences of the atomic bomb. His conclusion was that the bombing of Hiroshima was not the final point of the second war, but itís the starting point of the third one, the cold war. After that there were many, many problems about the bomb. It was more complicated than that, maybe. It happens that people occasionally choose one side or the other, and after that it was more difficult. But my parents were much involved. In fact, so much involved that when in 1948 my mother came to the States — in fact, she was invited by a group of anti-fascists Spanish groups to support Spanish refugees, The States more or less recognized Franco power in Spain, instead of supporting the Spanish government elected before the war. And when my mother came to the States, she was taken to Ellis Island. That was what happened.
Niroomand-Rad:She was taken to?
Langevin-Joliot:Ellis Island, because they didnít want her to enter the States.
Niroomand-Rad:Oh my God.
Langevin-Joliot:So, there was protestation, and finally she was allowed.
She was allowed to come to the U.S.
Langevin-Joliot:Yes. It was a pleasant surprise for her. The problem was not so serious, but thinking about the trip she has made with Marie Curie in the States in 1921, and thinking not to be allowed to enter the States! But it was during the McCarthy period and all that. So that was not physics; that was politics.
Niroomand-Rad:Actually, since that incident, then in scientific community they started to be very concerned about the regulations and having linear no threshold model for the radiation risk, and that we are still using it as of today in calculating the radiation risk in the working place. I recall you commented onÖ
Langevin-Joliot:Professor Tubiana often said that he spent half his life to call physicist and physician attention on radiation hazard, and than now he spends the remaining part of his life to tell people not to fear so much radiation.
Niroomand-Rad:Yes. Could you share that with us?
Langevin-Joliot:Yes, because I always was in a discussion about radiation risk, and the radiation was diminishing the level that was allowed, and in some cases the public now fears radiation so much. Professor Tubiana was a young physician at the end of the war and studied in my fatherís lab. And his comment recently was I spend half of my life explaining to physicians and physicists and chemists take care more of radiation hazards. And now I am obliged because of what happened. I need to spend the second part of my life to claim as far as I can to everybody donít fear so much radiation, because we have had a huge benefit of radiation in the past, and we will have a lot of benefits in the future if you use it properly. So itís a serious situation.
Niroomand-Rad:But unfortunately, I guess the political scientists are still hanging on to these linear no threshold model and use that as the risk for the public perceptions. And it is hard for the true scientist to really get into media and regulatory to talk about the benefits of radiations, and the fact that the low level radiations can be beneficial and believe in an ocean of radiation on earth.
Langevin-Joliot:I would say. I will not discuss this point, because I am not a specialist of radiation physics, especially of the effect of radiation in light of disuse. I donít wish to discuss so much of that. But I start with natural radioactivity and I explain to people that life is born in a radioactive earth. Earth is like it is because of uranium and radium and all these radioactive elements inside and which gives energy, so that the Earth is not completely cold inside. Otherwise it will be cold and dead. So life has a lot to do with radiation.
Langevin-Joliot:But it is difficult for people to understand the difference of establishing a regulation to be sure that people take care, and predicting what happens if you are in the region of this low dose. In fact, nobody knows the answer. And itís reasonable to take care, but itís unreasonable to say all those people will die because they have this quantity of dose. And the only answer, in my opinion, is to increase the level of general scientific culture interpreting about statistics about the fact that the answers will not always be yes or no when you discuss with scientists many things like that.
Niroomand-Rad:So what is your message to the general public who are so fearful of radiation? What would you say to them? How can we as a scientist help to reduce this fear?
Langevin-Joliot:First, to know that natural radiation exists. You have some seven thousand Becquerels inside of you, so donít be worried so much if there are some few hundred somewhere in the room. So that is one way. And if you take a plane, you take radiation because the level of cosmic rays is much higher than it is on the Earth, and if you are living in the mountain itís increased, and a number of things like that. So it would be good that people know about thatÖThe other thing is to compare the benefit and the risk, which is not simple. The appreciation of that, it is normal that they change with time. Sometime I have the discussion about the fact to put radioactive waste underground. It is certainly necessary to have very, very serious studies about how the soil is underground, how an underground storage may behave. I donít say just take that and put it in the hole and forget about it. Things that we have to take care for a long time. But when I have people speaking about one million years, it is true that some radioisotopes have such kind of half-life. I find that unreasonable. Nobody could have any idea about the way human societies may change over such times. Or even if they will survive due to so many unexpected events. I say okay, what will be the monitor in one million years from now. Either everything has improved so much that the problem of radiation and the risk of radiation will be easily solved, okay, suppose these things come underground that something happens, they will be much more cleaver than we have to do something with. Either the civilization will decrease and drop and you have war and everything is bad, and we will come back to the prehistoric states. Why not? One million years. You cannot dream of that. And they would say in this case no matter. Those guys who live a short time, then the problem of radiation is nothing. So I donít want to discuss what happens with the storage inside for one million years. Itís stupid.
Niroomand-Rad:Yes, it doesnít make sense.
Langevin-Joliot:And it is very serious to take care for three hundred years or maybe a few thousands or something like that, at most.
Niroomand-Rad:Tell us about your family: your husband, what he does, and your children.
Langevin-Joliot:My husband was a nuclear physicist also. And he unfortunately died 17 years ago now. Long time now. My son is an astrophysicist, and my daughter is Director of Human resources in a government agency for milk, butter, and cheese products in France.
Niroomand-Rad:Your son is interested in astrophysics. Is your daughter also interested in any sciences?
Langevin-Joliot:She was very good at science, but she was also interested in history so she shifted to history, she chooses to study history. Then as a young person she decided to do something else.
Niroomand-Rad:I just want to trace back the interest in art and poetry from Marie, because Marie at the time was considered always very much enjoying poetry, and she was writing some poetry herself.
Langevin-Joliot:Yes, as a young person she wrote a few things, but not of importance.
Niroomand-Rad:Did your mother also have some interest in poetry?
Langevin-Joliot:My mother loved poetry and copied some poetry and she even translated some poetry from English. My mother was not good at speaking English, but she read it very well and she loved the English writings.
Niroomand-Rad:How about yourself?
Langevin-Joliot:Occasionally. That may be in time, maybe I donít. I never wrote anything for myself.
Niroomand-Rad:But you enjoy?
Langevin-Joliot:I enjoy it.
Niroomand-Rad:And the artistic talent, I guess your Aunt Eve, who is still alive and living in New York. Could you tell us little bit about your Aunt?
Langevin-Joliot:Maybe more on the artistic side, but she was quite possibly ok in science — She was not against it. I would say that her life was different, so she was interested in piano and some writing in the newspapers. She was asked by an editor in the U.S. to write her well-known book: Madam Curie. Then war broke out, the second war, so she came first to England where she spoke at BBC for the Free French, then to the States. Then she was asked and she decided to become a war journalist for six months, and she visited a number of places in a very difficult condition. Her trip was through Africa and the Soviet Union and Moscow at the time of the battle for Moscow. And then she traveled back and got inside China, that was in war with the Japanese. She entered the Free French Army, came back to France with the army. Later she was a journalist and took an important assistant job at the NATO organization. After that she married Harry Labouisse, an American diplomat who was at that time in charge of the refugees in Liban(?). And later he became Director of UNICEF for a long time, maybe 15 years. So she had spent a lot of time lecturing about her books. She was very active all her life. She cannot remain as active, but she is very well.
Niroomand-Rad:I was really impressed talking to her a few days ago, at the age of 98, she is so alert.
Langevin-Joliot:So, maybe we stop now.
Niroomand-Rad:Thank you for giving your time to us.
Langevin-Joliot:Thank you. Yes.