Ernst Rexer
Encyclopedia
Ernst Rexer was a German
nuclear physicist
. He worked on the German nuclear energy program during World War II. After the war, he was sent to Laboratory V, in Obninsk, to work on the Soviet atomic bomb project. In 1956, he was sent to East Germany, where he was a professor and director of the Institute for the Application of Radioactive Isotopes at the Technische Hochschule Dresden.
and physics
at the Albert-Ludwigs-Universität Freiburg
. In 1926 he completed the Chemikerverbandsexamen (Chemist Federation exam). From 1926 to 1929, he worked in the Osram Werke
(Osram Works), in Weisswasser and Berlin
. In 1929, he received his doctorate from the Friedrich-Wilhelms-Universität (today, the Humboldt-Universität zu Berlin
).
. In 1936, he completed his Habilitation
there, with an Habilitationsschrift on the physics of crystals. In 1937, he joined the faculty at Halle as a Dozent
(lecturer).
In 1938, Rexer took a position in the armaments industry where he investigated plastics.
The German nuclear energy project
, also known as the Uranverein (Uranium Club), was initiated in 1939, shortly after the discovery of nuclear fission
. By September, the Heereswaffenamt (HWA, Army Ordnance Office) squeezed out the Reichsforschungsrat
(RFR, Reich Research Council) of the Reichserziehungsministerium
(REM, Reich Ministry of Education) and began its control over the project, under the direction of Kurt Diebner
. Rexer was brought into the project. By 1942 it was apparent that the nuclear energy project would not make a decisive contribution to ending the war effort in the near term and HWA control of the project was transferred to the RFR. At that time, Rexer and his colleagues, including Heinz Pose
, were transferred to the Physikalisch-Technische Reichsanstalt
(PTR). Abraham Esau
was President of the PTR, and he took control of the Uranverein in December, when he was appointed Plenipotentiary (Bevollmächtiger) for Nuclear Physics.
While Rexer was at the PTR, some of the research was carried out at the Versuchsstelle (testing station) of the HWA in Gottow; Kurt Diebner
, was director of the facility. The testing station is where Rexer, F. Berkei, W. Borrmann, W. Czulius, Kurt Diebner
, Georg Hartwig, Karl-Heinz Höcker
, Walter Herrmann
, and Heinz Pose
, compared the effectiveness of neutron production in a paraffin-moderated reactor using uranium plates, rods, and cubes. Internal reports (See section below: Internal Reports.) on their activities were classified Top Secret and had limited distribution. The G-1 experiment performed at the HWA testing station had lattices of 6,800 uranium oxide cubes (about 25 tons) in the neutron moderator paraffin. Their work verified Höcker’s calculations that cubes were better than rods, and rods were better than plates.
In 1944, Rexer was appointed professor at the Physikalischen Institut (Physics Institute) at the Universität Leipzig
.
sent special search teams into Germany to locate and deport German nuclear scientists or any others who could be of use to the Soviet atomic bomb project
. The Russian Alsos
teams were headed by NKVD
Colonel General A. P. Zavenyagin and staffed with numerous scientists, from their only nuclear laboratory, attired in NKVD officer’s uniforms. In the autumn of 1945, Pose was offered the opportunity to work in the Soviet Union, which he accepted. He arrived in the Soviet Union, with his family, in February 1946. He was to establish and head Laboratory V (also known by the code name Malojaroslavets-10, after the nearby town by the same name) in Obninsk
. The scientific staff at Laboratory V was to be both Russian and German, the former being mostly political prisoners from the Gulag
or exiles; this type of facility is known as a Sharashka
. (Laboratory B
in Sungul’ was also a sharashka and its personnel worked on the Soviet atomic bomb project. Notable Germans at Laboratory B were Hans-Joachim Born
, Alexander Catsch
, Nikolaus Riehl
, and Karl Zimmer
. Notable Russians from the Gulag were N. V. Timofeev-Resovskij and S. A. Voznesenskij.)
On 5 March 1946, in order to staff his laboratory, Pose and NKVD General Kravchenko, along with two other officers, went to Germany for six months to hire scientists. Additionally, Pose procured equipment from the companies AEG
, Zeiss, Schott Jena
, and Mansfeld, which were in the Russian occupation zone.
Pose planned 16 laboratories for his institute, which was to include a chemistry laboratory and eight laboratories. Three heads of laboratories, Czulius, Herrmann, and Rexer, were Pose’s colleagues who worked with him at the German Army’s testing station in Gottow, under the Uranverein project. (See below: Internal Reports.) Eight laboratories in the institute were:
). Other notable German scientists, who worked on the Soviet atomic bomb project and joined Rexer at the Technische Hochschule Dresden were Heinz Pose
and two other physicists, Werner Hartmann
and Heinz Barwich
, who had been at Gustav Hertz’s Institute G, in Agudseri (Agudzery).
(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
.
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
nuclear physicist
Nuclear physics
Nuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei. The most commonly known applications of nuclear physics are nuclear power generation and nuclear weapons technology, but the research has provided application in many fields, including those...
. He worked on the German nuclear energy program during World War II. After the war, he was sent to Laboratory V, in Obninsk, to work on the Soviet atomic bomb project. In 1956, he was sent to East Germany, where he was a professor and director of the Institute for the Application of Radioactive Isotopes at the Technische Hochschule Dresden.
Education
In 1923, Rexer began studies in chemistryChemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
and physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
at the Albert-Ludwigs-Universität Freiburg
University of Freiburg
The University of Freiburg , sometimes referred to in English as the Albert Ludwig University of Freiburg, is a public research university located in Freiburg im Breisgau, Baden-Württemberg, Germany.The university was founded in 1457 by the Habsburg dynasty as the...
. In 1926 he completed the Chemikerverbandsexamen (Chemist Federation exam). From 1926 to 1929, he worked in the Osram Werke
Osram
Osram, founded 1919, is part of the industry sector of Siemens AG and one of the two leading lighting manufacturers in the world. The name is derived from osmium and Wolfram , as both these elements were commonly used for lighting filaments at the time the company was founded...
(Osram Works), in Weisswasser and Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
. In 1929, he received his doctorate from the Friedrich-Wilhelms-Universität (today, the Humboldt-Universität zu Berlin
Humboldt University of Berlin
The Humboldt University of Berlin is Berlin's oldest university, founded in 1810 as the University of Berlin by the liberal Prussian educational reformer and linguist Wilhelm von Humboldt, whose university model has strongly influenced other European and Western universities...
).
Early years
After receipt of his doctorate in 1929, Rexer became an associate assistant (außerplanmäßiger Assistant) at the Institut für Theoretische Physik (Institute for Theoretical Physics) at the Martin-Luther-Universität Halle-WittenbergUniversity of Halle-Wittenberg
The Martin Luther University of Halle-Wittenberg , also referred to as MLU, is a public, research-oriented university in the cities of Halle and Wittenberg within Saxony-Anhalt, Germany...
. In 1936, he completed his Habilitation
Habilitation
Habilitation is the highest academic qualification a scholar can achieve by his or her own pursuit in several European and Asian countries. Earned after obtaining a research doctorate, such as a PhD, habilitation requires the candidate to write a professorial thesis based on independent...
there, with an Habilitationsschrift on the physics of crystals. In 1937, he joined the faculty at Halle as a Dozent
Docent
Docent is a title at some European universities to denote a specific academic appointment within a set structure of academic ranks below professor . Docent is also used at some universities generically for a person who has the right to teach...
(lecturer).
In 1938, Rexer took a position in the armaments industry where he investigated plastics.
The German nuclear energy project
German nuclear energy project
The German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
, also known as the Uranverein (Uranium Club), was initiated in 1939, shortly after the discovery of nuclear fission
Nuclear fission
In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...
. By September, the Heereswaffenamt (HWA, Army Ordnance Office) squeezed out the Reichsforschungsrat
Reichsforschungsrat
The Reichsforschungsrat was created in Germany in 1937 under the Education Ministry for the purpose of centralized planning of all basic and applied research, with the exception of aeronautical research...
(RFR, Reich Research Council) of the Reichserziehungsministerium
Reichserziehungsministerium
The Reichserziehungsministerium was officially known as the Reichsministerium für Wissenschaft, Erziehung und Volksbildung .-Background:...
(REM, Reich Ministry of Education) and began its control over the project, under the direction of Kurt Diebner
Kurt Diebner
Kurt Diebner was a German nuclear physicist who is well known for directing and administrating the German nuclear energy project, a secretive program aiming to built weapon of mass destruction for the Nazi Germany during the course of World War II...
. Rexer was brought into the project. By 1942 it was apparent that the nuclear energy project would not make a decisive contribution to ending the war effort in the near term and HWA control of the project was transferred to the RFR. At that time, Rexer and his colleagues, including Heinz Pose
Heinz Pose
Rudolf Heinz Pose was a German nuclear physicist.He did pioneering work which contributed to the understanding nuclear energy levels. He worked on the German nuclear energy project Uranverein. After World War II, the Soviet Union sent him to establish and head Laboratory V in Obninsk...
, were transferred to the Physikalisch-Technische Reichsanstalt
Physikalisch-Technische Bundesanstalt
The Physikalisch-Technische Bundesanstalt is based in Braunschweig and Berlin. It is the national institute for natural and engineering sciences and the highest technical authority for metrology and physical safety engineering in Germany....
(PTR). Abraham Esau
Abraham Esau
Robert Abraham Esau was a German physicist.After receipt of his doctorate from the University of Berlin, Esau worked at Telefunken, where he pioneered very high frequency waves used in radar, radio, and television, and he was president of the Deutscher Telefunken Verband...
was President of the PTR, and he took control of the Uranverein in December, when he was appointed Plenipotentiary (Bevollmächtiger) for Nuclear Physics.
While Rexer was at the PTR, some of the research was carried out at the Versuchsstelle (testing station) of the HWA in Gottow; Kurt Diebner
Kurt Diebner
Kurt Diebner was a German nuclear physicist who is well known for directing and administrating the German nuclear energy project, a secretive program aiming to built weapon of mass destruction for the Nazi Germany during the course of World War II...
, was director of the facility. The testing station is where Rexer, F. Berkei, W. Borrmann, W. Czulius, Kurt Diebner
Kurt Diebner
Kurt Diebner was a German nuclear physicist who is well known for directing and administrating the German nuclear energy project, a secretive program aiming to built weapon of mass destruction for the Nazi Germany during the course of World War II...
, Georg Hartwig, Karl-Heinz Höcker
Karl-Heinz Höcker
Karl-Heinz Höcker was a German theoretical nuclear physicist who worked in the German Uranverein. After World War II, he worked at the university of Stuttgart and was the founder of the Institut für Kernenergetik und Energiesysteme.-Education:From 1935 to 1940, Höcker studied at the University of...
, Walter Herrmann
Walter Herrmann (physicist)
Walter Herrmann was a German nuclear physicist who worked on the German nuclear energy project during World War II...
, and Heinz Pose
Heinz Pose
Rudolf Heinz Pose was a German nuclear physicist.He did pioneering work which contributed to the understanding nuclear energy levels. He worked on the German nuclear energy project Uranverein. After World War II, the Soviet Union sent him to establish and head Laboratory V in Obninsk...
, compared the effectiveness of neutron production in a paraffin-moderated reactor using uranium plates, rods, and cubes. Internal reports (See section below: Internal Reports.) on their activities were classified Top Secret and had limited distribution. The G-1 experiment performed at the HWA testing station had lattices of 6,800 uranium oxide cubes (about 25 tons) in the neutron moderator paraffin. Their work verified Höcker’s calculations that cubes were better than rods, and rods were better than plates.
In 1944, Rexer was appointed professor at the Physikalischen Institut (Physics Institute) at the Universität Leipzig
University of Leipzig
The University of Leipzig , located in Leipzig in the Free State of Saxony, Germany, is one of the oldest universities in the world and the second-oldest university in Germany...
.
In the Soviet Union
Near the close of World War II, the Soviet UnionSoviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
sent special search teams into Germany to locate and deport German nuclear scientists or any others who could be of use to the Soviet atomic bomb project
Soviet atomic bomb project
The Soviet project to develop an atomic bomb , was a clandestine research and development program began during and post-World War II, in the wake of the Soviet Union's discovery of the United States' nuclear project...
. The Russian Alsos
Russian Alsos
The Russian Alsos was an operation which took place in early 1945 in Germany, Austria, and Czechoslovakia, and whose objectives were the exploitation of German atomic related facilities, intellectual materials, materiel resources, and scientific personnel for the benefit of the Soviet atomic bomb...
teams were headed by NKVD
NKVD
The People's Commissariat for Internal Affairs was the public and secret police organization of the Soviet Union that directly executed the rule of power of the Soviets, including political repression, during the era of Joseph Stalin....
Colonel General A. P. Zavenyagin and staffed with numerous scientists, from their only nuclear laboratory, attired in NKVD officer’s uniforms. In the autumn of 1945, Pose was offered the opportunity to work in the Soviet Union, which he accepted. He arrived in the Soviet Union, with his family, in February 1946. He was to establish and head Laboratory V (also known by the code name Malojaroslavets-10, after the nearby town by the same name) in Obninsk
Obninsk
Obninsk is a city in Kaluga Oblast, Russia, located southwest of Moscow. Population: Obninsk is one of the major Russian science cities. The first nuclear power plant in the world for the large-scale production of electricity opened here on June 27, 1954, and it also doubled as a training...
. The scientific staff at Laboratory V was to be both Russian and German, the former being mostly political prisoners from the Gulag
Gulag
The Gulag was the government agency that administered the main Soviet forced labor camp systems. While the camps housed a wide range of convicts, from petty criminals to political prisoners, large numbers were convicted by simplified procedures, such as NKVD troikas and other instruments of...
or exiles; this type of facility is known as a Sharashka
Sharashka
Sharashka was an informal name for secret research and development laboratories in the Soviet Gulag labor camp system...
. (Laboratory B
Laboratory B in Sungul’
Laboratory B in Sungul’ was one of the laboratories under the 9th Chief Directorate of the NKVD that contributed to the Soviet atomic bomb project. It was created in 1946 and closed in 1955, when some of its personnel were merged with the second Soviet nuclear design and assembly facility. It was...
in Sungul’ was also a sharashka and its personnel worked on the Soviet atomic bomb project. Notable Germans at Laboratory B were Hans-Joachim Born
Hans-Joachim Born
Hans-Joachim Born was a German radiochemist trained and educated at the Kaiser-Wilhelm-Institut für Chemie. Up to the end of World War II, he worked in Nikolaj Vladimirovich Timofeev-Resovskij’s Abteilung für Experimentelle Genetik, at the Kaiser-Wilhelm-Institut für Hirnforschung. He was taken...
, Alexander Catsch
Alexander Catsch
Alexander Catsch was a German-Russian medical doctor and radiation biologist. Up to the end of World War II, he worked in Nikolaj Vladimirovich Timefeev-Resovskij’s Abteilung für Experimentelle Genetik at the Kaiser-Wilhelm-Institut für Hirnforschung...
, Nikolaus Riehl
Nikolaus Riehl
Nikolaus Riehl was a German industrial nuclear chemist. He was head of the scientific headquarters of Auergesellschaft. When the Russians entered Berlin near the end of World War II, he was invited to the Soviet Union, where he stayed for 10 years...
, and Karl Zimmer
Karl Zimmer
Karl Günter Zimmer was a German physicist and radiation biologist, known for his work on the effects of ionizing radiation on DNA. In 1935, he published the major work, Über die Natur der Genmutation und der Genstruktur, with N. V...
. Notable Russians from the Gulag were N. V. Timofeev-Resovskij and S. A. Voznesenskij.)
On 5 March 1946, in order to staff his laboratory, Pose and NKVD General Kravchenko, along with two other officers, went to Germany for six months to hire scientists. Additionally, Pose procured equipment from the companies AEG
AEG
Allgemeine Elektricitäts-Gesellschaft was a German producer of electrical equipment founded in 1883 by Emil Rathenau....
, Zeiss, Schott Jena
Schott Glass
SCHOTT AG is a German manufacturer of high-quality industrial glass products, its main markets are household appliances, pharmaceutical industries, solar energy, electronics, optics as well as automotive...
, and Mansfeld, which were in the Russian occupation zone.
Pose planned 16 laboratories for his institute, which was to include a chemistry laboratory and eight laboratories. Three heads of laboratories, Czulius, Herrmann, and Rexer, were Pose’s colleagues who worked with him at the German Army’s testing station in Gottow, under the Uranverein project. (See below: Internal Reports.) Eight laboratories in the institute were:
- Heinz Pose’s laboratory for nuclear processes.
- Werner Czulius’s laboratory for uranium reactors.
- Walter Herrmann’sWalter Herrmann (physicist)Walter Herrmann was a German nuclear physicist who worked on the German nuclear energy project during World War II...
laboratory for special issues of nuclear disintegration. - Westmayer’s laboratory for systematic nuclear reactions.
- Professor Carl Friedrich Weiss’s laboratory for the study of natural and artificial radioactivity.
- Schmidt’s laboratory to study methodologies for nuclear measurement.
- Professor Ernst Rexer’s laboratory for applied nuclear physics.
- Hans Jürgen von Oertzen’s laboratory to study cyclotrons and high voltage.
Return to Germany
In preparation for release from the Soviet Union, it was standard practice to put personnel into quarantine for a few years if they worked on projects related to the Soviet atomic bomb project, which Rexer did. After quarantine, he was sent to the Deutsche Demokratische Republik (DDR, German Democratic Republic) in 1956. He was appointed extraordinarius professor and Director of the Institutes für die Anwendung radioaktiver Isotope (Institute for the Application of Radioactive Isotopes) at the Technische Hochschule Dresden (today, Technische Universität DresdenDresden University of Technology
The Technische Universität Dresden is the largest institute of higher education in the city of Dresden, the largest university in Saxony and one of the 10 largest universities in Germany with 36,066 students...
). Other notable German scientists, who worked on the Soviet atomic bomb project and joined Rexer at the Technische Hochschule Dresden were Heinz Pose
Heinz Pose
Rudolf Heinz Pose was a German nuclear physicist.He did pioneering work which contributed to the understanding nuclear energy levels. He worked on the German nuclear energy project Uranverein. After World War II, the Soviet Union sent him to establish and head Laboratory V in Obninsk...
and two other physicists, Werner Hartmann
Werner Hartmann (physicist)
Werner Hartmann was a German physicist who introduced microelectronics into East Germany. He studied physics at the Technische Hochschule Berlin and worked at Siemens before joining Fernseh GmbH...
and Heinz Barwich
Heinz Barwich
Heinz Barwich was a German nuclear physicist. He was deputy director of the Siemens Research Laboratory II in Berlin. At the close of World War II, he went to the Soviet Union for ten years to work on the Soviet atomic bomb project, for which he received a Stalin Prize...
, who had been at Gustav Hertz’s Institute G, in Agudseri (Agudzery).
Internal Reports
The following reports were published in Kernphysikalische ForschungsberichteKernphysikalische Forschungsberichte
Kernphysikalische Forschungsberichte was an internal publication of the German Uranverein, which was initiated under the Heereswaffenamt in 1939; in 1942, supervision of the Uranverein was turned over to the Reichsforschungsrat under the Reichserziehungsministerium...
(Research Reports in Nuclear Physics), an internal publication of the German Uranverein
German nuclear energy project
The German nuclear energy project, , was an attempted clandestine scientific effort led by Germany to develop and produce the atomic weapons during the events involving the World War II...
. 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
Operation Alsos
Operation Alsos was an effort at the end of World War II by the Allies , branched off from the Manhattan Project, to investigate the German nuclear energy project, seize German nuclear resources, materials and personnel to further American research and to prevent their capture by the Soviets, and...
and sent to the United States Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...
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
American Institute of Physics
The American Institute of Physics promotes science, the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies...
.
- F. Berkei, W. Borrmann, W. Czulius, Kurt Diebner, Georg Hartwig, K. H. Höcker, W. Herrmann, H. Pose, and Ernst Rexer Bericht über einen Würfelversuch mit Uranoxyd und Paraffin (dated before 26 November 1942). G-125.
- Heinz Pose and Ernst Rexer Versuche mit verschiedenen geometrischen Anordnungen von Uranoxyd und Paraffin (12 October 1943). G-240.
Selected literature
- Ernst Rexer Additive Verfärbung von Alkalihalogenidkristallen II. Ultramikroskopische Diffusionsbefunde, Zeitschrift für Physik Volume 76, Numbers 11-12, 735-755, (1932). Institutional affiliation: Institut für theoretische Physik, Halle, Saale. The article was received on 12 May 1932.