Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction, Nature, 224, Nov
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Otto Stern Annalen 4.11.11
(To be published by Annalen der Physik in December 2011) Otto Stern (1888-1969): The founding father of experimental atomic physics J. Peter Toennies,1 Horst Schmidt-Böcking,2 Bretislav Friedrich,3 Julian C.A. Lower2 1Max-Planck-Institut für Dynamik und Selbstorganisation Bunsenstrasse 10, 37073 Göttingen 2Institut für Kernphysik, Goethe Universität Frankfurt Max-von-Laue-Strasse 1, 60438 Frankfurt 3Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6, 14195 Berlin Keywords History of Science, Atomic Physics, Quantum Physics, Stern- Gerlach experiment, molecular beams, space quantization, magnetic dipole moments of nucleons, diffraction of matter waves, Nobel Prizes, University of Zurich, University of Frankfurt, University of Rostock, University of Hamburg, Carnegie Institute. We review the work and life of Otto Stern who developed the molecular beam technique and with its aid laid the foundations of experimental atomic physics. Among the key results of his research are: the experimental test of the Maxwell-Boltzmann distribution of molecular velocities (1920), experimental demonstration of space quantization of angular momentum (1922), diffraction of matter waves comprised of atoms and molecules by crystals (1931) and the determination of the magnetic dipole moments of the proton and deuteron (1933). 1 Introduction Short lists of the pioneers of quantum mechanics featured in textbooks and historical accounts alike typically include the names of Max Planck, Albert Einstein, Arnold Sommerfeld, Niels Bohr, Max von Laue, Werner Heisenberg, Erwin Schrödinger, Paul Dirac, Max Born, and Wolfgang Pauli on the theory side, and of Wilhelm Conrad Röntgen, Ernest Rutherford, Arthur Compton, and James Franck on the experimental side. However, the records in the Archive of the Nobel Foundation as well as scientific correspondence, oral-history accounts and scientometric evidence suggest that at least one more name should be added to the list: that of the “experimenting theorist” Otto Stern. -
Lise Meitner 1878 – 1968
Discoveries that changed the world: 1932 – 1942 James Chadwick 1891 – 1974 Lise Meitner 1878 – 1968 I „The road to the neutron“ Staff and research students at the Cavendish Laboratory, Cambridge, 1923. (Names from left to right. Front row: J. Chadwick, G. Stead, F.W. Aston, Prof. Sir J. J. Thomson, Prof. Sir E. Rutherford, J.A. Crowther, Miss B. Trevelyan, G.I. Taylor, Second row: P. Kapitza, H. de W. Smyth, T. Alty, J.E. Crackston, H. Robinson, L.F. Curtiss, E.S. Bieler, A.G.D. West, P. Mercier. Back row: P.M.S. Blackett, R.E. Clay, H.W.B. Skinner, H.D. Griffith, A.W. Barton, L.F. Bates, J.S. Rogers, K.G. Emeleus.) The room which Rutherford and Chadwick used for their scattering experiments in the 1920s. The work was carried out in the dark, often to the accompaniment of Rutherford singing „Onward Christian Soldiers“. Rutherford had already proposed the neutron in 1920 in his Bakerian Lecture at the Royal Society. He talked about a “neutral doublet” (at that time considered a proton and electron) that could be difficult to detect and move easily through matter. Curie & Joliot published (incorrectly) in Jan. 1932 the observation: 9Be + 4He → 12C + 1n I. Curie and F. Joliot, C. R. Acad. Sci. Paris 194, 273 (1932) When the radiation was passed through wax the ionisation increased! This increase was due to knock-on protons. To explain this the Curie’s suggested that the emission was of a 55 MeV γ ray, an energy much greater than anything yet seen! Moreover, the radiation also passed through lead This experiment was first performed in 1930 by Walter Bothe and Herbet Becker at U. -
Otto Stern Annalen 22.9.11
September 22, 2011 Otto Stern (1888-1969): The founding father of experimental atomic physics J. Peter Toennies,1 Horst Schmidt-Böcking,2 Bretislav Friedrich,3 Julian C.A. Lower2 1Max-Planck-Institut für Dynamik und Selbstorganisation Bunsenstrasse 10, 37073 Göttingen 2Institut für Kernphysik, Goethe Universität Frankfurt Max-von-Laue-Strasse 1, 60438 Frankfurt 3Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6, 14195 Berlin Keywords History of Science, Atomic Physics, Quantum Physics, Stern- Gerlach experiment, molecular beams, space quantization, magnetic dipole moments of nucleons, diffraction of matter waves, Nobel Prizes, University of Zurich, University of Frankfurt, University of Rostock, University of Hamburg, Carnegie Institute. We review the work and life of Otto Stern who developed the molecular beam technique and with its aid laid the foundations of experimental atomic physics. Among the key results of his research are: the experimental determination of the Maxwell-Boltzmann distribution of molecular velocities (1920), experimental demonstration of space quantization of angular momentum (1922), diffraction of matter waves comprised of atoms and molecules by crystals (1931) and the determination of the magnetic dipole moments of the proton and deuteron (1933). 1 Introduction Short lists of the pioneers of quantum mechanics featured in textbooks and historical accounts alike typically include the names of Max Planck, Albert Einstein, Arnold Sommerfeld, Niels Bohr, Werner Heisenberg, Erwin Schrödinger, Paul Dirac, Max Born, and Wolfgang Pauli on the theory side, and of Konrad Röntgen, Ernest Rutherford, Max von Laue, Arthur Compton, and James Franck on the experimental side. However, the records in the Archive of the Nobel Foundation as well as scientific correspondence, oral-history accounts and scientometric evidence suggest that at least one more name should be added to the list: that of the “experimenting theorist” Otto Stern. -
A Fateful Year for a Physicist
FLASHBACK_Nuclear Fission A fateful year for a physicist For Lise Meitner, 1938 is something like a turning point in her life. She flees the Nazis and goes to Sweden, where she tries to establish herself as a scientist and finds the solution to a problem that Otto Hahn told her about in a letter. As a result, the former researcher at the Kaiser Wilhelm Institute for Chemistry becomes one of the co-discoverers of nuclear fission. TEXT SUSANNE KIEWITZ July 1938. Lise Meitner flees from Germany, her adopted country The scientific community tries to support Lise Meitner as best since 1907. After the annexation of her native country of Austria, it can, but ultimately with little success. As the best option of- she is at grave risk of falling victim to the anti-Semitic persecu- fered is a temporary job at the Nobel Institute in Stockholm, she tion in the Third Reich. At the urging of friends and colleagues – decides to go to Sweden. Yet the disappointment is great. “At most notably Otto Hahn – Meitner finally decided with a heavy the Institute, I have a workroom which is also my study and ex- heart to emigrate to Sweden. For her, it is the end of an era. In re- periment room with lots of people coming and going,” writes signing from the Kaiser Wilhelm Institute for Chemistry in Berlin, Meitner in frustration to her friend Gertrud Schiemann in Berlin the almost sixty-year-old scientist is giving up a hard-won, pres- at the end of October 1938. tigious position in her profession. -
The Manhattan Project: Making the Atomic Bomb” Is a Short History of the Origins and Develop- Ment of the American Atomic Bomb Program During World War H
f.IOE/MA-0001 -08 ‘9g [ . J vb JMkirlJkhilgUimBA’mmml — .— Q RDlmm UNITED STATES DEPARTMENT OF ENERGY ,:.. .- ..-. .. -,.,,:. ,.<,.;<. ~-.~,.,.- -<.:,.:-,------—,.--,,p:---—;-.:-- ---:---—---- -..>------------.,._,.... ,/ ._ . ... ,. “ .. .;l, ..,:, ..... ..’, .’< . Copies of this publication are available while supply lasts from the OffIce of Scientific and Technical Information P.O. BOX 62 Oak Ridge, TN 37831 Attention: Information Services Telephone: (423) 576-8401 Also Available: The United States Department of Energy: A Summary History, 1977-1994 @ Printed with soy ink on recycled paper DO13MA-0001 a +~?y I I Tho PROJEOT UNITED STATES DEPARTMENT OF ENERGY F.G. Gosling History Division Executive Secretariat Management and Administration Department of Energy ]January 1999 edition . DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. I DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. 1 Foreword The Department of Energy Organization Act of 1977 brought together for the first time in one department most of the Federal Government’s energy programs. -
RIGHT and WRONG ROADS to the DISCOVERY of NUCLEAR ENERGY by Lise Meitner
RIGHT AND WRONG ROADS TO THE DISCOVERY OF NUCLEAR ENERGY by Lise Meitner Twenty years ago, on 2 December 1942, Enrico Fermi succeeded in making the world's first reactor "critical", i.e. in bringing it into operation. It was no accident that Fermi was the first man to solve what was then an extremely complicated problem, although a simple one in principle. In both the experimental and theoretical fields, he was one of the most gifted physicists of our time, always ready and able to ap proach new and difficult problems with the simplest of conceptions and, if the available facilities were not adequate, to develop or devise experimental methods (again in the simplest manner) with an amazing power of analysis of the task in hand. The basis for Fermi's achievement in construc ting the first reactor was of course the discovery, by Otto Hahn and Fritz Strassmann, of uranium fission through neutron bombardment of ordinary uranium. Viewed in the light of our present knowledge, the road to that discovery was astonishingly long and to a cer tain extent the wrong one, yet here also, in following this devious path which led at last to the true expla nation of events, Fermi was the pioneer. Very soon after the discovery of the neutron by Chadwick and of artificial radioactivity by I. Curie and F. Joliot, Fermi recognized how suitable neu trons must be, due to the absence of an electric charge, for penetrating heavier, i. e. highly-charged, Lise Meitner (Photo USIS) atomic nuclei and bringing about reactions in them. -
Lise Meitner, Austrian Nuclear Physicist Research Questions – Possible Answers
Lise Meitner, Austrian Nuclear Physicist Research Questions – Possible Answers 1. What were Meitner’s greatest accomplishments? - In 1905, she became the second woman to receive a doctorate in physics from the University of Vienna. - She was the first woman Professor of Physics in Germany. - Theoretical explanation of nuclear fission. - Earlier, she discovered new isotopes of the element protactinium. 2. How was Meitner viewed in the workplace and the scientific community at large? - Her research and collaboration was valued by Otto Hahn, her collaborator. However, Hahn did not defend her when other people denigrated her research. - Other physicists, including Albert Einstein, greatly admired Meitner’s work and thought she was more capable than Hahn. - Because she was a woman, there were many places she was not allowed to work, and many people who did not respect her research. 3. Who was Meitner influenced by in her scientific career and with whom did she collaborate? - Received her position at the Institute of Theoretical Physics in Berlin from Max Planck. - She collaborated with Otto Hahn, a chemist, for several decades. - She worked with her nephew, Otto Frisch, to explain the results of nuclear fission. 4. What sacrifices did Meitner make for her career? - She did not marry or have long-term romantic relationships. - She worked for no pay as a “guest” at several times in her career. - She was forced out of the Kaiser Wilhelm Institute and to flee Germany due to anti-Jewish laws. She moved to Sweden to continue working. - She was not allowed in the classrooms of the University of Berlin, working in the basement of the Chemical Institute. -
Meitnerium in Tribute
in your element Meitnerium in tribute Adrian Dingle tells the story of how the name of element 109 represents the lasting recognition that one of the greatest nuclear physicists was in danger of never receiving. hile the furious and well- and 19975, producing two and twelve atoms, documented bickering between respectively. In addition Dubna and Berkeley Cold War adversaries over each confirmed the existence of 266Mt through W 208 the discovery priority for many of the another reaction, this time between Pb transfermium elements was raging in the and 59Co, with the Americans reporting it 1950s and 1960s (mostly involving the in 20096. Current research has identified a Lawrence Berkeley National Laboratory number of isotopes ranging in mass from and the Joint Institute for Nuclear Research 266 to 278 — almost exclusively α-emitters — in Dubna), a new player in super-heavy with 277Mt undergoing spontaneous fission. synthesis was emerging: the GSI Helmholtz Those isotopes have half-lives ranging from Centre for Heavy Ion Research, founded in just milliseconds to up to a few seconds, the Darmstadt in the old West Germany in 1969. heavier ones being the longest lived. It wasn’t long before the team there, led by Thus, it has not been possible to carry out Peter Armbruster and Gottfried Münzenberg, chemical studies on meitnerium (even at the laid claim to the syntheses of new elements, one-atom-at-a-time level), and its chemical starting with element 107 in 1981, and 109 a and physical properties remain largely those year later. In the original experiment that of educated speculation through theoretical yielded a single atom of what came to be calculation and by analogy with other group known as meitnerium, a 209Bi target was 9 and period 7 elements. -
Story of Fission Unlocking Power of the Nucleus
GENERAL ARTICLE Story of Fission Unlocking Power of the Nucleus Amit Roy The discovery of nuclear fission is the culmination of sus- tained efforts involving many scientists led by Hahn and Meitner to understand the production of artificial radioactiv- ity induced by neutrons bombarding uranium. The large energy release in this process was almost immediately used for both military and civilian purposes. It also started the large- scale funding of scientific research by governments across the Amit Roy is currently at the Variable Energy world. Nuclear energy is one of the clean sources of energy Cyclotron Centre after and contributes very little to global warming. working at Tata Institute of Fundamental Research The discovery of fission of uranium in 1939 changed forever the and Inter-University way society at large supported scientific research. Till that time, Accelerator Centre. His individual researchers or small groups would pursue their sub- research interests are in nuclear, atomic and jects of interest with whatever resources they could muster either accelerator physics. from government or private individuals. With fission promising the prospect of energy release of unprecedented amounts, govern- ments all across the globe started funding research in a big way leadingtobigorganisedresearchbylargeteams. How did it all begin? It all started with the chance discovery of radioactivity in 1896 by Henri Becquerel, which paved the way for the study of matter at the atomic scale for the first time. J J Thomson showed that atoms were no longer indivisible with his discovery of the electron in 1897. The radiations emitted by radioactive elements were identified in the works of Ernest Rutherford and Frederick Soddy at Montreal and Pierre Curie in Paris. -
Lise Meitner's Life and Synopsis of Nuclear Physics
LISE MEITNER’S LIFE AND SYNOPSIS OF NUCLEAR PHYSICS day of Birth in Vienna ___________________ 7.11.1878 finishes compulsory _____________________ 1892 school for girls finishes training as ______________________ 1895 __________ Wilhelm Conrad Röntgen primary school teacher incidentally discovers X-rays in for French Würzburg 1896 __________ Henri Becquerel discovers radiation of Uranium in Paris 1897 __________ J.J. Thomson detects the electron as first elementary particle 1898 __________ Marie and Pierre Curie discover radium in Paris 1900 __________ Max Planck introduces his concept of the Wirkungsquantum (quantum of action) successfully completes final ______________ 1901 __________ first Nobel Prize of Physics to exams as an external; begins W.C. Röntgen studies of physics at the University of Vienna 1903 __________ Ernest Rutherford classifies radiation as α-, β- and γ-rays 1905 __________ Albert Einstein’s 3 essential papers published, among them the spezielle Relativitätstheorie (special theory of relativity) graduation in Vienna ___________________ 1906 moves to Berlin, begins advanced _______ 1907 studies at Planck’s institute; collaboration with Otto Hahn begins discovery of the radioactive _____________ 1909 recoil (radioaktiver Rückstoß) with Hahn 1911 __________ First Solvay-conference in Brussels 1913 __________ Ernest Rutherford and Niels Bohr develop the „planetary model of atoms“, having a heavy nucleus in its centre begins working in the ___________________ 1912 Kaiser-Wilhelm-Institute Berlin, at first as unpaid guest -
The Actinide Research Quarterly Actinide Concept Is Blessed with the Guest Article “Source of the Ac- Tinide Concept” by Dr
Summer 1997 Los Alamos National Laboratory • A U.S. Department of Energy Laboratory The Actinide Research 55 Quarterly TA o f t h e N u c l e a r M a t e r i a l s T e c h n o l o g y D i v i s i o n In This Issue Source of the Actinide Concept by Dr. Glenn T. Seaborg 1 Source of the This issue of the Actinide Research Quarterly Actinide Concept is blessed with the guest article “Source of the Ac- tinide Concept” by Dr. Glenn Seaborg. One could 4 not ask for a more significant and timely introduction to the “Plutonium Futures—The Science” conference NMT Division than the personal perspective of the discoverer of the Recycles, Purifies element. The Santa Fe conference will also feature Plutonium-238 Dr. Seaborg’s plenary lecture videotaped in April this Oxide Fuel for Future year. In reminiscing about the past and anticipating Space Missions the future, we hope that this conference helps to her- ald a new beginning in the future science of actinides. 6 K. C. Kim New Mexico Welcomes My romance with the transuranium ele- "Plutonium ments started 63 years ago, in 1934, soon after Futures—The I became a chemistry graduate student at the Science" Conference University of California, Berkeley. These were the undiscovered elements with atomic num- 7 bers greater than 92 (the atomic number of "Plutonium uranium), the heaviest naturally occurring XBC 942-905 Lawrence Berkeley National Laboratory Futures—The element. Science" Conference We (the transuranium elements and I) the chemical properties using the periodic Program were first introduced at the weekly chemistry table as it was then known. -
How Heavy Will We Get?
books & arts How heavy will we get? Superheavy: Making (mendelevium). Superheavy manages to for example, through moscovium (115), and Breaking the precisely describe the intricate physical livermorium (116) or tennessine (117). Periodic Table phenomena at play, all the while rendering a It is difficult enough to explain the deep and mesmerizing sense of excitement at discovery and implications of each element the idea of crafting nature’s building blocks. of the period table to chemistry, physics Equally captivating is the essential role and engineering students. Chapman By Kit Chapman of the geopolitical context that defined how accomplished no small feat with this page each new tile of the periodic table was filled. turner; it provides a fascinating insight into In his quest to capture the essence of element the motivations and challenges of heavy- creation, Chapman takes us on a worldwide element science that should appeal to anyone BLOOMSBURY SIGMA: journey, from the first American secrets of with even a small interest in understanding 2019. 304 PP. £16.99 the atomic bomb to the fall of the U.S.S.R., how scientific innovations shape our world. and illustrates perfectly how historical events Discovering new elements is not merely onsidered the 150th anniversary of influenced the erecting of the large US about glory; as Chapman rightly states, the discovery of the periodic system, National Laboratory network or the ever- “every isotope unlocks a little more of the C2019 was proclaimed the International growing accelerator facilities in Sweden, universe or creates options for saving lives Year of the Periodic Table of Chemical Germany, Japan and Russia that have been through medical isotopes or cleaner energy.” Elements by the United Nations General instrumental in heavy-element research.