Johannes Hans Daniel Jensen

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Hans Jensen (1963)

Johannes Hans Daniel Jensen (born June 25, 1907 in Hamburg ; † February 11, 1973 in Heidelberg ; also known as Hans Jensen for short) was a German physicist and Nobel Prize winner . As a theoretical physicist, he created the shell model of the atomic nucleus around the same time as Maria Goeppert-Mayer, who was also awarded the Nobel Prize for this . The main place of activity after 1949 was the University of Heidelberg .

Life

Hans Jensen was born on June 25, 1907 as the third child of the gardener Karl Friedrich Jensen and his wife Helene Auguste Adolphine (née Ohm). From 1926 he studied physics , mathematics , physical chemistry and philosophy at the University of Hamburg and the Albert Ludwigs University in Freiburg im Breisgau . After completing his doctorate in physics with Wilhelm Lenz , he stayed as a research assistant in Hamburg and completed his habilitation in 1936. He was appointed lecturer in 1937 and associate professor at the Technical University of Hanover in 1941 . In 1949 he received a call to full professor from the Ruprecht-Karls-Universität Heidelberg , which he held until his retirement in 1969. During this time he also held several visiting professorships in the USA , including at the Institute for Advanced Study in Princeton (1952), the University of Wisconsin (1951), the University of Minnesota (1956), Indiana University (1953), at California Institute of Technology (1953) and Berkeley (1952), the University of California at La Jolla (1961). From 1955 he was co-editor of the Zeitschrift für Physik together with Otto Haxel . He was buried in Partenstein (Bavaria).

Grave slab

The following anecdote is characteristic of the person Hans Jensen :

“When Jensen was asked by the Prime Minister of the country the morning after the announcement of the Nobel Prize ceremony whether he had a special request, he immediately said: yes, you can grant German citizenship to a stateless student who has been expelled from Iraq. The student received it. "

Jensen married the doctor Elisabeth Behm in 1933. His daughter was the Roman Catholic theologian Anne Jensen .

plant

Jensen memorial plaque at the Institute for Theoretical Physics at Heidelberg University

Jensen's first works, u. a. his dissertation and habilitation dealt with refinements of the statistical Thomas-Fermi model of the atomic shell , which brought significant improvements. At the end of the 1930s he began to study the atomic nucleus . As early as 1939, in a largely empirical analysis of atomic nuclei, their binding energies and frequencies, he spoke of a shell model for the first time, but without going beyond the pure terminology. This formulation, however, was very vague, since on the one hand, the drop model of Bohr , the (1936) nuclear reactions described very good and the idea of paths seemed to have the nucleus no sense. Further development was delayed by the isolation of Germany in World War II , so that Jensen was only able to deal more intensively with the subject again at the end of the 1940s. It was not until 1948 that he achieved the breakthrough for an explanation of the magic numbers (published with Otto Haxel , Hans E. Suess ) by assuming a strong spin-orbit coupling USA Maria Goeppert-Mayer on the same result after Enrico Fermi had suggested the possibility of a strong spin-orbit coupling. As a result, there was a lively exchange between Jensen and Goeppert-Mayer, which led to an almost complete understanding of the properties of the lighter atomic nuclei. In 1955 the two published a detailed account of the understanding of atomic nuclei in the book Elementary Theory of Nuclear Shell Structure . For this achievement, the two were awarded half of the Nobel Prize in Physics in 1963 in equal parts; the other half went to Eugene Wigner .

In 1950, together with Helmut Steinwedel, he described giant resonances with a two-fluid model of proton and neutron fluid. In 1955 he and his student Berthold Stech introduced chiral symmetry into the theory of weak interaction, a forerunner of the later VA theory by Richard Feynman and Murray Gell-Mann (1958).

NSDAP membership

Despite concerns, he was a member of the NSDAP . The reason for this is said to have been that his wife would otherwise not have been allowed to continue her medical studies. During the time of National Socialism, he and others prevented the deportation of a Jewish physicist.

Awards

The J. Hans D. Jensen Prize of the Klaus Tschira Foundation, which is associated with visiting professorships for theoretical physicists at the University of Heidelberg, is named after him.

literature

Fonts

  • with Haxel, Suess: On the 'magic numbers' in nuclear structure, Phys. Rev., Volume 75, 1949, p. 1766
  • with Haxel, Suess: On the interpretation of the excellent nucleon numbers in the structure of the atomic nucleus, Naturwissenschaften, Volume 35, 1949, p. 376, Volume 36, 1949, pp. 153, 155
  • with Haxel, Suess: Model-based interpretation of the excellent nucleon numbers in nuclear structures, Zeitschrift für Physik, Volume 128, 1950, pp. 295–311
  • with Haxel, Suess: The shell model of the atomic nucleus, results of exact natural sciences 26, 1952, pp. 244–290
  • with Maria Goeppert-Mayer: Elementary theory of nuclear shell structure, Wiley 1955

Web links

Commons : Hans Daniel Jensen  - Collection of images, videos and audio files

Individual evidence

  1. ↑ mainpost.de
  2. ↑ uni-heidelberg.de: JHDJensen, life and work
  3. ^ Obituary for Anne Jensen (PDF) accessed on August 28, 2017
  4. ↑ Haxel, Jensen, Suess: On the “Magic Numbers” in Nuclear Structure , Physical Review, Volume 75, 1949, p. 1766, For the interpretation of the excellent nucleon numbers in the construction of the atomic nucleus , Natural Sciences, Volume 35, 1949, model interpretation of the excellent Nucleon numbers in nuclear structures , Natural Sciences, Volume 36, 1949, Model-based interpretation of the excellent nucleon numbers in nuclear structures , Zeitschrift für Physik, Volume 128, 1950, pp. 295-311
  5. ↑ Curriculum Vitae Prof. Dr. Johannes HD Jensen (PDF) Leopoldina. Retrieved February 27, 2019.
personal data
SURNAME Jensen, Johannes Hans Daniel
ALTERNATIVE NAMES Jensen, J. Hans D .; Jensen, Hans Daniel; Jensen, Johannes Daniel
BRIEF DESCRIPTION German physicist and Nobel Prize winner
DATE OF BIRTH June 25, 1907
PLACE OF BIRTH Hamburg
DATE OF DEATH February 11, 1973
Place of death Heidelberg