Johannes Hans Daniel Jensen (25 June 1907 – 11 February 1973) was a German nuclear physicist. During World War II, he worked on the German nuclear energy project, known as the Uranium Club, in which he made contributions to the separation of uranium isotopes. After the war Jensen was a professor at the University of Heidelberg. He was a visiting professor at the University of Wisconsin–Madison, the Institute for Advanced Study, University of California, Berkeley, Indiana University, and the California Institute of Technology.
J. Hans D. Jensen
Johannes Hans Daniel Jensen
25 June 1907
|Died||11 February 1973 (aged 65)|
|Alma mater||University of Hamburg|
|Awards||Nobel Prize for Physics (1963)|
|Doctoral advisor||Wilhelm Lenz|
|Doctoral students||Hans-Arwed Weidenmüller|
Jensen studied physics, mathematics, physical chemistry, and philosophy at the Albert-Ludwigs-Universität Freiburg and the University of Hamburg from 1926 to 1931, and he received his doctorate at the latter in 1932 under Wilhelm Lenz. Jensen completed his Habilitation in 1936 at the University of Hamburg.
In 1937 Jensen was Privatdozent (unpaid lecturer) at the University of Hamburg and began working with Paul Harteck, director of the university's physical chemistry department and advisor to the Heereswaffenamt (HWA, Army Ordnance Office) on explosives. Harteck and his teaching assistant Wilhelm Groth made contact with the Reichskriegsministerium (RKM, Reich Ministry of War) on 24 April 1939 to tell them of potential military applications of nuclear chain reactions. Military control of the German nuclear energy project, also known as the Uranverein (Uranium Club), began on 1 September 1939, the day that Nazi Germany initiated World War II by invading Poland. Harteck, one of the principals in the Uranverein, brought Jensen into the project. Jensen's main thrust was on double centrifuges for separation of uranium isotopes (see the section below citing internal reports of the Uranverein). Harteck and Jensen developed a double centrifuge based on a rocking process (Schaukelverfahren) to facilitate the separation effect.
In 1941 Jensen was named extraordinarius professor of theoretical physics at the Technische Hochschule Hannover (today, the University of Hanover), and in 1946 he became an ordinarius professor there. In 1949 he was appointed ordinarius professor at the Ruprecht Karl University of Heidelberg; since 1969 he was emeritus praecox. He was a guest professor at the University of Wisconsin–Madison (1951), the Institute for Advanced Study (1952), University of California, Berkeley (1952), Indiana University (1953), California Institute of Technology (1953), University of Minnesota, Twin Cities (1956), and University of California, San Diego (1961).
In 1963 Jensen shared half of the Nobel Prize in Physics with Maria Goeppert-Mayer for their proposal of the nuclear shell model; the remaining half of the prize was awarded to Eugene Wigner for unrelated work in nuclear and particle physics, especially through the application of fundamental symmetry principles.
Adolf Hitler took power on 30 January 1933. On 7 April of that year the Law for the Restoration of the Professional Civil Service was enacted; this law, and its subsequent related ordinances, politicized the education system in Germany. Other factors enforcing the politicization of education were Nationalsozialistische Deutsche Arbeiterpartei (NSDAP, National Socialist German Workers Party) organizations in academia and the rise of the Deutsche Physik movement, which was anti-Semitic and had a bias against theoretical physics, especially including quantum mechanics. The Party organizations were the Nationalsozialistischer Deutscher Studentenbund (NSDStB, National Socialist German Student League) founded in 1926, the Nationalsozialistischer Lehrerbund (NSLB, National Socialist Teachers League) founded in 1927, and the Nationalsozialistischer Deutscher Dozentenbund (NSDDB, National Socialist German University Lecturers League) founded in 1933. While membership in the NSDDB was not mandatory, it was tactically advantageous, if not unavoidable, as the district leaders had a decisive role in the acceptance of an Habilitationsschrift, which was a prerequisite to attaining the rank of Privatdozent necessary to becoming a university lecturer.
While all German universities were politicized, not all were as strict in carrying out this end as was the University of Hamburg, where Jensen received his doctorate and Habilitationsschrift. Upon his 1936 habilitation he had been a member of NSDDB for three years, the NSLB for two years, and a candidate for membership in NSDAP, which he received the next year. The university leader of NSLB had made it clear that active participation was expected from Jensen, and that is what they got.
After World War II the denazification process began. When Jensen faced the proceedings, he turned to Werner Heisenberg, a prominent member of the Uranverein, for a testament to his character – a document known as a Persilschein (whitewash certificate). Heisenberg was a particularly powerful writer of these documents, as he had never been a member of NSDAP, he had publicly clashed with NSDAP and the Schutzstaffel (SS), and he had been appointed by the British occupation authorities to the chair for theoretical physics and the directorship of the Max-Planck Institut für Physik then in Göttingen. Heisenberg wrote the document and convinced the authorities that Jensen had only joined the Party organizations to avoid unnecessary difficulties in academia.
The following reports were published in Kernphysikalische Forschungsberichte (Research Reports in Nuclear Physics), an internal publication of the German Uranverein. The reports were classified Top Secret, they had very limited distribution, and the authors were not allowed to keep copies. The reports were confiscated under the Allied Operation Alsos and sent to the United States Atomic Energy Commission for evaluation. In 1971 the reports were declassified and returned to Germany. The reports are available at the Karlsruhe Nuclear Research Center and the American Institute of Physics.
was a common year starting on Tuesday of the Gregorian calendar and a common year starting on Monday of the Julian calendar, the 1907th year of the Common Era (CE) and Anno Domini (AD) designations, the 907th year of the 2nd millennium, the 7th year of the 20th century, and the 8th year of the 1900s decade. As of the start of 1907, the Gregorian calendar was
13 days ahead of the Julian calendar, which remained in localized use until 1923.1907 in Germany
Events in the year 1907 in Germany.1963 in science
The year 1963 in science and technology involved some significant events, listed below.1973 in Germany
Events in the year 1973 in Germany.1973 in science
The year 1973 in science and technology involved some significant events, listed below.Hans-Arwed Weidenmüller
Hans-Arwed Weidenmüller (born 26 July 1933 in Dresden) is a German theoretical physicist, who works primarily in the field of nuclear physics.Hans Jensen
Hans Jensen may refer to:
Hans Jacob Arnold Jensen (1777–1853), Norwegian military officer and politician
Hans G. Jensen (1856–1922), Norwegian trade unionist and politician
Hans Johan Jensen (1882–?), Norwegian politician
J. Hans D. Jensen (1907–1973), German nuclear physicist
Hans Jensen (Norway) (1817–1888), Norwegian businessperson and politician
Hans Arne Jensen, Danish botanist, agronomist and writerJohannes Jensen
Johannes Jensen may refer to:
Johannes V. Jensen (1873–1950), Danish author
J. Hans D. Jensen (1907–1973), German nuclear physicist
Johannes Jensen (aviator) (1898–1978), German World War I flying ace
Johannes Robert Jensen (1916–1984), Danish field hockey playerList of Nobel laureates affiliated with the University of California, Berkeley
This list of Nobel laureates affiliated with the University of California, Berkeley comprehensively shows the alumni, faculty members as well as researcher of the University of California, Berkeley who were awarded the Nobel Prize and the Nobel Memorial Prize in Economic Sciences. The Nobel Prizes, established by the 1895 will of Alfred Nobel, are awarded to individuals who make outstanding contributions in the fields of Chemistry, Literature, Peace, Physics, and Physiology or Medicine. An associated prize, the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel (commonly known as the Nobel Prize in Economics), was instituted by Sweden's central bank, Sveriges Riksbank, in 1968 and first awarded in 1969.As of October 2018, 107 Nobel laureates have been affiliated with UC Berkeley, and 48 of them are officially listed as "Berkeley's Nobel Laureates" by UC Berkeley for being graduates (obtained degrees), current faculty members, or deceased faculty who retired at Berkeley. Among the 107 laureates, 34 are Berkeley alumni (graduates and attendees), and 40 have been long-term academic members of the Berkeley faculty or Berkeley-affiliated research organizations. Subject-wise, 33 laureates have won the Nobel Prize in Physics, more than any other subject. In addition, Linus Pauling is the only UC Berkeley-affiliated Nobel laureate (Visiting Lecturer in Physics and Chemistry, 1929–1934) to win two Nobel prizes: he won the Nobel Prize in Chemistry in 1954 and the Nobel Peace Prize in 1962; since this is a list of laureates, not prizes, he is counted only once.List of University of Freiburg people
This is a list of notable alumni and academics of the University of Freiburg. 10 Nobel laureates are associated with the university and 13 researchers have been honored with the Gottfried Wilhelm Leibniz Prize since it was first awarded in 1986.List of female Nobel laureates
As of 2018, Nobel Prizes have been awarded to 853 men, 51 women (Marie Curie won it twice), and 24 unique organizations.The distribution of female Nobel Laureates is as follows:
seventeen women have won the Nobel Peace Prize,
fourteen have won the Nobel Prize in Literature,
twelve have won the Nobel Prize in Physiology or Medicine,
five have won the Nobel Prize in Chemistry,
three have won the Nobel Prize in Physics,
and one, Elinor Ostrom, has won the Nobel Memorial Prize in Economic Sciences.The first woman to win a Nobel Prize was Marie Curie, who won the Nobel Prize in Physics in 1903 with her husband, Pierre Curie, and Henri Becquerel. Curie is also the only woman to have won multiple Nobel Prizes; in 1911, she won the Nobel Prize in Chemistry. Curie's daughter, Irène Joliot-Curie, won the Nobel Prize in Chemistry in 1935, making the two the only mother-daughter pair to have won Nobel Prizes.The most Nobel Prizes awarded to women in a single year was in 2009, when five women became laureates in four categories.
The most recent women to be awarded a Nobel Prize were Donna Strickland in Physics, Frances Arnold in Chemistry, and Nadia Murad for Peace (2018).Maria Goeppert-Mayer Award
The Maria Goeppert-Mayer Award is an annual prize presented by the American Physical Society in recognition of an outstanding contribution to physics research by a woman. It recognizes and enhances outstanding achievements by women physicists in the early years of their careers.The prize has been awarded since 1986 and is named after Maria Goeppert-Mayer, Nobel laureate in 1963 with J. Hans D. Jensen and Eugene Paul Wigner. Goeppert-Mayer and Jensen were awarded their prize "for their discovery of the nuclear shell structure".
Goeppert-Mayer was the second woman to receive a Nobel prize in physics after Marie Curie.Maria Goeppert Mayer
Maria Goeppert Mayer (June 28, 1906 – February 20, 1972) was a German-born American theoretical physicist, and Nobel laureate in Physics for proposing the nuclear shell model of the atomic nucleus. She was the second woman to win a Nobel Prize in physics, the first being Marie Curie.
A graduate of the University of Göttingen, Goeppert Mayer wrote her doctoral thesis on the theory of possible two-photon absorption by atoms. At the time, the chances of experimentally verifying her thesis seemed remote, but the development of the laser permitted this. Today, the unit for the two-photon absorption cross section is named the Goeppert Mayer (GM) unit.
Maria Goeppert married Joseph Edward Mayer and moved to the United States, where he was an associate professor at Johns Hopkins University. Strict rules against nepotism prevented Johns Hopkins University from taking her on as a faculty member, but she was given a job as an assistant and published a landmark paper on double beta decay in 1935. In 1937, she moved to Columbia University, where she took an unpaid position. During World War II, she worked for the Manhattan Project at Columbia on isotope separation, and with Edward Teller at the Los Alamos Laboratory on the development of the Teller's "Super" bomb.
After the war, Goeppert Mayer became a voluntary associate professor of Physics at the University of Chicago (where Teller and her husband worked) and a senior physicist at the nearby Argonne National Laboratory. She developed a mathematical model for the structure of nuclear shells, for which she was awarded the Nobel Prize in Physics in 1963, which she shared with J. Hans D. Jensen and Eugene Wigner. In 1960, she was appointed full professor of physics at the University of California, San Diego.Nuclear shell model
In nuclear physics and nuclear chemistry, the nuclear shell model is a model of the atomic nucleus which uses the Pauli exclusion principle to describe the structure of the nucleus in terms of energy levels. The first shell model was proposed by Dmitry Ivanenko (together with E. Gapon) in 1932. The model was developed in 1949 following independent work by several physicists, most notably Eugene Paul Wigner, Maria Goeppert Mayer and J. Hans D. Jensen, who shared the 1963 Nobel Prize in Physics for their contributions.
The shell model is partly analogous to the atomic shell model which describes the arrangement of electrons in an atom, in that a filled shell results in greater stability. When adding nucleons (protons or neutrons) to a nucleus, there are certain points where the binding energy of the next nucleon is significantly less than the last one. This observation, that there are certain magic numbers of nucleons: 2, 8, 20, 28, 50, 82, 126 which are more tightly bound than the next higher number, is the origin of the shell model.
The shells for protons and for neutrons are independent of each other. Therefore, "magic nuclei" exist in which one nucleon type or the other is at a magic number, and "doubly magic nuclei", where both are. Due to some variations in orbital filling, the upper magic numbers are 126 and, speculatively, 184 for neutrons but only 114 for protons, playing a role in the search for the so-called island of stability. Some semimagic numbers have been found, notably Z=40 giving nuclear shell filling for the various elements; 16 may also be a magic number.In order to get these numbers, the nuclear shell model starts from an average potential with a shape something between the square well and the harmonic oscillator. To this potential a spin orbit term is added. Even so, the total perturbation does not coincide with experiment, and an empirical spin orbit coupling must be added with at least two or three different values of its coupling constant, depending on the nuclei being studied.
Nevertheless, the magic numbers of nucleons, as well as other properties, can be arrived at by approximating the model with a three-dimensional harmonic oscillator plus a spin-orbit interaction. A more realistic but also complicated potential is known as Woods–Saxon potential.Otto Haxel
Otto Haxel (2 April 1909, in Neu-Ulm – 26 February 1998, in Heidelberg) was a German nuclear physicist. During World War II, he worked on the German nuclear energy project. After the war, he was on the staff of the Max Planck Institute for Physics in Göttingen. From 1950 to 1974, he was an ordinarius professor of physics at the University of Heidelberg, where he fostered the use of nuclear physics in environmental physics; this led to the founding of the Institute of Environmental Physics in 1975. During 1956 and 1957, he was a member of the Nuclear Physics Working Group of the German Atomic Energy Commission. From 1970 to 1975, he was the Scientific and Technical Managing Director of the Karlsruhe Research Center.
Haxel was a signatory of the Manifesto of the Göttingen Eighteen.Timeline of women in science in the United States
This is a timeline of women in science in the United States.
1848: Maria Mitchell became the first woman elected to the American Academy of Arts and Sciences; she had discovered a new comet the year before.
1853: Jane Colden was the only female biologist mentioned by Carl Linnaeus in his masterwork Species Plantarum.
1889: Mary Emilie Holmes became the first female Fellow of the Geological Society of America.
1893: Florence Bascom became the second woman to earn her Ph.D in geology in the United States, and the first woman to receive a Ph.D from Johns Hopkins University. Geologists consider her to be the "first woman geologist in this country [America]."
1896: Florence Bascom became the first woman to work for the United States Geological Survey.
1901: Florence Bascom became the first female geologist to present a paper before the Geological Survey of Washington.
1912: Henrietta Swan Leavitt studied the bright-dim cycle periods of Cepheid stars, then found a way to calculate the distance from such stars to Earth.
1924: Florence Bascom became the first woman elected to the Council of the Geological Society of America.
1925: Florence Sabin became the first woman elected to the National Academy of Science.
1928: Alice Evans became the first woman elected president of the Society of American Bacteriologists.
1936: Edith Patch became the first female president of the Entomological Society of America.
1942: American geologist Marguerite Williams became the first African-American woman to receive a PhD in geology in the United States. She completed her doctorate, entitled A History of Erosion in the Anacostia Drainage Basin, at Catholic University.
1947: Gerty Cori became the first woman to receive the Nobel Prize in Physiology or Medicine, which she received along with Carl Ferdinand Cori "for their discovery of the course of the catalytic conversion of glycogen", and Bernardo Alberto Houssay "for his discovery of the part played by the hormone of the anterior pituitary lobe in the metabolism of sugar".
1950: Isabella Abbott became the first Native Hawaiian woman to receive a PhD in any science; hers was in botany.
1950: Esther Lederberg was the first to isolate lambda bacteriophage, a DNA virus, from Escherichia coli K-12.
1952: Grace Hopper completed what is considered to be the first compiler, a program that allows a computer user to use English-like words instead of numbers. It was known as the A-0 compiler.
1956: The Wu experiment was a nuclear physics experiment conducted in 1956 by the physicist Chien-Shiung Wu, born in China but having become an American citizen in 1954, in collaboration with the Low Temperature Group of the US National Bureau of Standards. That experiment showed that parity could be violated in weak interaction.
1960: Rosalyn Yalow received the Nobel Prize in Physiology or Medicine "for the development of radioimmunoassays of peptide hormones" along with Roger Guillemin and Andrew V. Schally who received it "for their discoveries concerning the peptide hormone production of the brain".
1963: Maria Goeppert Mayer became the first American woman to receive a Nobel Prize in Physics; she shared the prize with J. Hans D. Jensen "for their discoveries concerning nuclear shell structure” and Eugene Paul Wigner "for his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry principles". She was born in Poland, but became a U.S. citizen in 1933.
1965: Sister Mary Kenneth Keller became the first American woman to earn a Ph.D. in Computer Science. Her thesis was titled "Inductive Inference on Computer Generated Patterns."
1975: Chien-Shiung Wu, born in China but having become an American citizen in 1954, became the first female president of the American Physical Society.
1976: Margaret Burbidge, born in England, was named as the first female president of the American Astronomical Society.
1978: Anna Jane Harrison became the first female president of the American Chemical Society.
1978: Mildred Cohn served as the first female president of the American Society for Biochemistry and Molecular Biology, then called the American Society of Biological Chemists.
1983: Barbara McClintock received the Nobel Prize in Physiology or Medicine for her discovery of genetic transposition; she was the first woman to receive that prize without sharing it, and the first American woman to receive any unshared Nobel Prize.
1988: Gertrude B. Elion received the Nobel Prize in Physiology or Medicine along with James W. Black and George H. Hitchings "for their discoveries of important principles for drug treatment".
1991: Doris Malkin Curtis became the first woman president of the Geological Society of America.
1992: Edith M. Flanigen became the first woman awarded the Perkin Medal (widely considered the highest honor in American industrial chemistry) for her outstanding achievements in applied chemistry. The medal especially recognized her syntheses of aluminophosphate and silicoaluminophosphate molecular sieves as new classes of materials.
2004: Linda B. Buck received the Nobel Prize in Physiology or Medicine along with Richard Axel "for their discoveries of odorant receptors and the organization of the olfactory system".
2009: Carol W. Greider received the Nobel Prize in Physiology or Medicine along with Elizabeth H. Blackburn (Blackburn was a native of Australia, but lived in the United States since 1975, and became a naturalized citizen in September 2003) and Jack W. Szostak "for the discovery of how chromosomes are protected by telomeres and the enzyme telomerase".
2010: Marcia McNutt became the first female director of the United States Geological Survey.
2016: Marcia McNutt became the first woman president of the American National Academy of Sciences.
2018: Frances Arnold received the Nobel Prize in Chemistry "for the directed evolution of enzymes"; she shared it with George Smith and Gregory Winter, who received it "for the phage display of peptides and antibodies". This made Frances the first American woman to receive the Nobel Prize in Chemistry.
2019: Karen Uhlenbeck won the Abel Prize for "her pioneering achievements in geometric partial differential equations, gauge theory, and integrable systems, and for the fundamental impact of her work on analysis, geometry and mathematical physics." She is the first woman to win the prize.University of Hamburg
The University of Hamburg (German: Universität Hamburg, also referred to as UHH) is a comprehensive university in Hamburg, Germany. It was founded on 28 March 1919, having grown out of the previous General lecture system (Allgemeines Vorlesungswesen) and the Colonial Institute of Hamburg (Hamburgisches Kolonialinstitut) as well as the Akademic Gymnasium. In spite of its relatively short history, six Nobel Prize Winners and serials of scholars are affiliated to the university. The University of Hamburg is the biggest research and education institution in Northern Germany and one of the most extensive universities in Germany. The main campus is located in the central district of Rotherbaum, with affiliated institutes and research centres spread around the city state.
The institution is classified as a global top 200 university by frequently cited ranking systems such as the Times Higher Education Ranking, the Shanghai Ranking and the CWTS Leiden Ranking, placing it among the top 1% of global universities.On a national scale, U.S. News & World Report ranks UHH 7th and QS World University Rankings 14th out of a total of 426 German institutions of higher education.Wilhelm Lenz
Wilhelm Lenz (February 8, 1888 in Frankfurt am Main – April 30, 1957 in Hamburg) was a German physicist, most notable for his invention of the Ising model and for his application of the Laplace–Runge–Lenz vector to the old quantum mechanical treatment of hydrogen-like atoms.