Wolfgang Gentner

Wolfgang Gentner (23 July 1906 in Frankfurt am Main – 4 September 1980 in Heidelberg) was a German experimental nuclear physicist.

Gentner received his doctorate in 1930 from the University of Frankfurt. From 1932 to 1935 he had a fellowship which allowed him to do postdoctoral research and study at Cruie’s Radium Institute at the University of Paris. From 1936 to 1945, he was a staff scientist at the Institute of Physics at the Kaiser Wilhelm Institute for Medical Research, in Heidelberg. One of his areas of specialization was nuclear photoeffects. He was granted his Habilitation from the University of Frankfurt in 1937. At the end of 1938 and early 1939, he visited the Radiation Laboratory at the University of California Berkeley; upon his return to Germany, he participated in the construction of a cyclotron at Heidelberg. During World War II, he participated in the German nuclear energy project, also called the Uranium Club. After WW II, Gentner became a professor at the University of Freiberg.

In 1956, Gentner was appointed Director of the Synchrocyclotron Department at CERN. In 1958, he became director of the new Max Planck Institute for Nuclear Physics at Heidelberg. From 1967 to 1970, he was chairman of the Physicochemicl-technical Section of the Max Planck Society. From 1969 to 1971, he was President of the Science Policy Committee and President of the Council at CERN. From 1972, he was Vice-president of the Max Planck Society. From 1975, he was a member of the board of governors at the Weizmann Institute of Science, Israel.

Gentner helped found a number of European scientific organizations during the 1960s.

Education

From 1925 to 1930, Gentner studied at the " Friedrich-Alexander-Universität Erlangen-Nürnberg" and the " Johann Wolfgang Goethe-Universität Frankfurt am Main". While in his first semester at Erlangen, his father died, so he returned to Frankfurt to help care for his mother and continued his education at Frankfurt. He received his doctorate in 1930 under Friedrich Dessauer, who was Director of the "Institut für die physikalischen Grundlagen der Medizin" (Institute for the Physical Fundamentals of Medicine), at the University of Frankfurt. His thesis was on the range of electrons in matter and their biological effects. In 1932, he was an auxiliary aid ("Hilfsassistent") to Dessauer. From 1933 to 1935, he was a fellow of the "Oswalt-Stiftung" (Oswalt Foundation) of the University of Frankfurt and a fellow of the Carnegie Foundation, whose assistance he used to study at the Radium Institute of the University of Paris, which at that time was under the leadership of Marie Curie. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.] [ "Who is Who in CERN: Wolfgang Gentner", " [http://library.cern.ch/archives/biographies/Gentner_BW.pdf CERN Courier] " December 1960, February 1978, and November 1980.] [ " [http://nobelprize.org/nobel_prizes/medicine/articles/states/walther-bothe.html Walther Bothe] and the Physics Institute: the Early Years of Nuclear Physics", Nobelprize.org.]

Career

From 1936 to 1945, Gentner was a staff assistant at Walther Bothe’s "Institut für Physik" at the "Kaiser-Wilhelm Institut für medizinische Forschung" (KWImF, Kaiser Wilhelm Institute for Medical Research; today, the Max-Planck Institut für medizinische Forschung), in Heidelberg. One of his areas of specialization was in nuclear photoeffects ("Kernphotoeffekt"). [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.] [ " [http://nobelprize.org/nobel_prizes/medicine/articles/states/walther-bothe.html Walther Bothe] and the Physics Institute: the Early Years of Nuclear Physics", Nobelprize.org.] [ W. Bothe and W. Gentner "Herstellung neuer Isotope durch Kernphotoeffekt", "Die Naturwissenschaften" Volume 25, Issue 8, 126-126 (1937). Received 9 February 1937. Institutional affiliation: "Institut für Physik" at the "Kaiser-Wilhelm Institut für medizinische Forschung".] [ W. Gentner "Kernphotoeffekt unter gleichzeitiger Aussendung von zwei Neutronen", "Die Naturwissenschaften" Volume 26, Number 7, 109-109 (1938). Received 8 February 1938. Institutional affiliation: "Institut für Physik" at the "Kaiser-Wilhelm Institut für medizinische Forschung".]

In 1932, Walther Bothe had succeeded Philipp Lenard as Director of the "Physikalische und Radiologische Institut" (Physics and Radiological Institute) at the University of Heidelberg. When Adolf Hitler became Chancellor of Germany on 30 January 1933, the concept of " deutsche Physik" took on more favor as well as fervor; "deutsche Physik", was anti-Semitic and anti-theoretical physics, especially modern physics, including quantum mechanics and both atomic and nuclear physics. As applied in the university environment, political factors took priority over the historically applied concept of scholarly ability, [ Beyerchen, 1997, 141-167.] even though its two most prominent supporters were the Nobel Laureates in Physics Philipp Lenard [ Beyerchen, 1977, 79-102.] and Johannes Stark. [ Beyerchen, 1977, 103-140.] Supporters of "deutsche Physik" launched vicious attacks against leading theoretical physicists. While Lenard was retired from the University of Heidelberg, he still had significant influence there. In 1934, Lenard had managed to get Bothe relieved of his directorship of the Institute of Physics at the University of Heidelberg, whereupon Bothe was able to become the Director of the "Institut für Physik" of the KWImF, replacing Karl W. Hauser, who had recently died. Ludolf von Krehl, Director of th KWImF, and Max Planck, President of the Kaiser-Wilhelm Gesellschaft (KWG, Kaiser Wilhelm Society, today, the Max-Plank Gesellschaft), had offered the directorship to Bothe to ward off the possibility of his emigration. When it came time for Gentner to submit his "Habilitationsschrift", "Die Absorption, Streuung und Sekundärstrahlung harter Gamma-Strahlen" ("The absorption, scattering and secondary hard gamma rays"), the relations between the KWImF and the University of Heidelberg were so strained that "Habilitation" was not possible there. So, Gentner completed the requirements at the University of Frankfurt, in 1937, and became a "Privatdozent" (lecturer) there. This necessitated making trips by train between the facilities, which soon became a burden. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ " [http://nobelprize.org/nobel_prizes/medicine/articles/states/walther-bothe.html Walther Bothe] and the Physics Institute: the Early Years of Nuclear Physics", Nobelprize.org.] [ David M. States "A History of the Kaiser Wilhelm Institute for Medical Research: 1929-1939: Walther Bothe and the Physics Institute: The Early Years of Nuclear Physics", "Nobelprize.org" ( [http://nobelprize.org/nobel_prizes/medicine/articles/states/index.html 28 June 2001] ).] [ "Das Physikalische und Radiologische Institut der Universität Heidelberg", "Heidelberger Neueste Nachrichten" Volume 56 (7 March 1913).]

By the end of 1937, the rapid successes Bothe and Gentner had with the building and research uses of a Van de Graaf generator had led them to consider building a cyclotron. By November, a report had already been sent to the President of the "Kaiser-Wilhelm Gesellschaft" (KWG, Kaiser Wilhelm Society; today, the Max Planck Society), and Bothe began securing funds from the "Helmholtz-Gesellschaft" (Helmholtz Society; today, the "Helmholtz-Gemeinschaft"), the "Badischen Kultusministerium" (Baden Ministry of Culture), " I.G. Farben", the KWG, and various other research oriented agencies. Initial promises led to ordering a magnet from " Siemens" in September 1938, however, further financing then became problematic. In these times, Gentner continued his research on the nuclear photoeffect, with the aid of the van de Graaf generator, which had been upgraded to produce energies just under 1 MeV. When his line of research was completed with the ⁷Li (p, gamma) and the ¹¹B (p, gamma) reactions, and on the nuclear isomer ⁸⁰Br, Gentner devoted his full effort to the building of the planned cyclotron. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

In order to facilitate the construction of the cyclotron, at the end of 1938 and into 1939, with the help of a fellowship from the "Helmholtz-Gesellschaft", Gentner was sent to Radiation Laboratory of the University of California (today, the Lawrence Berkeley National Laboratory) in Berkeley, California. As a result of the vist, Gentner formed a cooperative relationship with Emilio G. Segrè and Donald Cooksey. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

The German nuclear energy project, also known as the "Uranverein", began in the spring of 1939 under the auspices of the "Reichsforschungsrat" (RFR, Reich Research Council) of the "Reichserziehungsministerium" (REM, Reich Ministry of Education). By 1 September, the "Heereswaffenamt" (HWA, Army Ordnance Office) squeezed out the RFR and took over the effort. Under the control of the HWA, the "Uranverein" had its first meeting on 16 September. The meeting was organized by Kurt Diebner, advisor to the HWA, and held in Berlin. The invitees included Walther Bothe, Siegfried Flügge, Hans Geiger, Otto Hahn, Paul Harteck, Gerhard Hoffmann, Josef Mattauch, and Georg Stetter. A second meeting was held soon thereafter and included Klaus Clusius, Robert Döpel, Werner Heisenberg, and Carl Friedrich von Weizsäcker. With Bothe being one of the principles, Gentner was soon drawn into work for the "Uranverein", along with other colleagues, such as Arnold Flammersfeld and Peter Herbert Jensen. Their research was published in the "Kernphysikalische Forschungsberichte" ("Research Reports in Nuclear Physics"); see below the section "Internal Reports". [ Hentschel and Hentschel, 1996, 363-364 and Appendix F; see the entries for Diebner and Döpel. See also the entry fro the KWIP in Appendix A and the entry for the HWA in Appendix B.] [ Kristie Macrakis "Surviving the Swastika: Scientific Research in Nazi Germany" (Oxford, 1993) pp. 164-169.] [ Jagdish Mehra and Helmut Rechenberg "The Historical Development of Quantum Theory. Volume 6. The Completion of Quantum Mechanics 1926-1941. Part 2. The Conceptual Completion and Extension of Quantum Mechanics 1932-1941. Epilogue: Aspects of the Further Development of Quantum Theory 1942-1999." (Springer, 2001) pp. 1010-1011.]

After the armistice between France and Germany in the summer of 1940, Bothe and Gentner received orders to inspect the cyclotron Frédéric Joliot-Curie had built in Paris. While it had been built, it was not yet operational. In September 1940, Gentner received orders to form a group to put the cyclotron into operation. Hermann Dänzer from the University of Frankfurt participated in this effort. While in Paris, Gentner was able to free both Frédéric Joliot-Curie and Paul Langevin, who had been arrested and detained. At the end of the winter of 1941/1942, the cyclotron was operational with a 7-MeV beam of deuterons. Uranium and thorium were irradiated with the beam, and the byproducts were sent to Otto Hahn at the "Kaiser-Wilhelm Institut für Chemie" (KWIC, Kaiser Wilhelm Institute for Chemistry, today, the Max Planck Institute for Chemistry), in Berlin. In mid-1942, Gentner’s successor in Paris, was Wolfgang Riezler from Bonn. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ Jörg Kummer" [http://www.physik.uni-frankfurt.de/paf/paf194.html Hermann Dänzer: 1904-1987] " (University of Frankfurt).] [ Thomas Powers "Heisneberg’s War: The Secret History of the German Bomb" (Knopf, 1993) 357.]

A next mission of the HWA was the completion of the Heidelberg cyclotron. It was during 1941 that Bothe had acquired all the necessary funding to complete construction. The magnet was delivered in March 1943, and the first beam of deuteron was emitted in December. The inauguration ceremony for the cyclotron was held on 2 June 1944. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

In 1941, Gentner was authorized as a "Dozent" (lecturer) with a "Lehrauftrag" (teaching assignment) at the University of Heidelberg. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.]

In 1946, Gentner became an "ordentlicher Professor" (ordinarius professor) at the " Albert-Ludwigs-Universität Freiburg", where he worked on nuclear and cosmic-ray physics. From 1947 to 1949, he was also "Prorektor" (Vice-Rector) of the University. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.]

During 1956 and 1957, Gentner was a member of the "Arbeitskreis Kernphysik" (Nuclear Physics Working Group) of the "Fachkommission II „Forschung und Nachwuchs“" (Commission II “Research and Growth”) of the "Deutschen Atomkommission" (DAtK, German Atomic Energy Commission). Other members of the Nuclear Physics Working Group in both 1956 and 1957 were: Werner Heisenberg (chairman), Hans Kopfermann (vice-chairman), Fritz Bopp, Walther Bothe, Otto Haxel, Willibald Jentschke, Heinz Maier-Liebnitz, Josef Mattauch, Wolfgang Riezler, Wilhelm Walcher, and Carl Friedrich von Weizsäcker. Wolfgang Paul was also a member of the group during 1957. [ Horst Kant "Werner Heisenberg and the German Uranium Project / Otto Hahn and the Declarations of Mainau and Göttingen", Preprint 203 (Max-Planck Institut für Wissenschaftsgeschichte, [http://www.mpiwg-berlin.mpg.de/Preprints/P203.PDF 2002] ).]

In 1956, soon after the founding of CERN, in Geneva, Gentner was appointed "Direktor der Abteilung Synchrozyklotron" (Director of the Synchrocyclotron Department) and "Direktor der Forschung" (Director of Research), positions which he held until October 1958. His department was responsible for the construction of their 600-MeV synchrocyclotron. Parallel to this, he had also been asked by the "Stuttgarter Landesregierung" (Stuttgart State Government) to be the first head of the "Kernforschungszentrum Karlsruhe" (KfK, Karlsruhe Nuclear Research Centre, today the "Forschungszentrum Karlsruhe"), whose construction had just been decided. Gentner declined so as to stay with more fundamental research, rather than applied. The synchrocyclotron at CERN delivered its first beam on 1 August 1957. From 1971 to 1974, he was chairman of the CERN board. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.] [ "Who is Who in CERN: Wolfgang Gentner", " [http://library.cern.ch/archives/biographies/Gentner_BW.pdf CERN Courier] " December 1960, February 1978, and November 1980.]

At the end of 1957, Gentner was in negotiations with Otto Hahn, President of the "Max-Planck Gesellschaft" (MPG, Max Planck Society, successor of the " Kaiser-Wilhelm Gesellschaft"), and with the Senate of the MPG to establish a new institute under their auspices. Essentially, Walther Bothe’s "Institut für Physik" at the "Max-Planck Institut für medizinische Forschung", in Heidelberg, was to be spun off and become a full fledged institute of the MPG. The decision to proceed was made in May 1958. Gentner was named the director of the "Max-Planck Institut für Kernphysik" (MPIK, Max Planck Institute for Nuclear Physics) on 1 October, and he also received the position as an "ordentlicher Professor" (ordinarius professor) at the University of Heidelberg. Bothe had not lived to see the final establishment of the MPIK, as he had died in February of that year. [ "Max Planck Institute for Nuclear Physics", " [http://www.innovations-report.com/html/profiles/profile-490.html Innovations Report] ".] [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

In 1959, in collaboration with his Heidelberg colleagues Otto Haxel and J. Hans D. Jensen, Gentner closed negotitations with the "Heidelberger Gemeinderates" (Heidelberg Local Council) to build a 6-Mev tandem-accelerator and a special building for the study of cosmic physics. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

From 1967 to 1970, Gentner was "Vorsitzender" (chairman) of the "physikalisch-chemisch-technischen Sektion" (Physicochemical-technical Section) of the " Max-Planck Gesellschaft". During this period, the "Max-Planck-Institut für Astronomie" (Max Planck Institute for Astronomy) was founded in Heidelberg. At the end of his term as section chairman, Gentner had two medical operations, one for cataracts, which were attributed to neutron radiation exposure from his early years of experimental nuclear research. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

At CERN, from 1969 to 1971, Gentner was "Vorsitzender des Wissenschaftsausschusses" (President of the Science Policy Committee) and from 1972 to 1974 "Präsident des Rates" (President of the Council). [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).] [ "Who is Who in CERN: Wolfgang Gentner", " [http://library.cern.ch/archives/biographies/Gentner_BW.pdf CERN Courier] " December 1960, February 1978, and November 1980.]

From 1972, Gentner was Vice-president of the " Max-Planck Gesellschaft". This was a particularly critical period for the MPG for purposes of consolidation, after 10 years of expansion. [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.]

From 1975, Gentner was a member of the board of governors at the Weizmann Institute of Science, in Israel. [ Hentschel and Hentschel, 1996, Appendix F; see the entry for Gentner.] [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

In the second half of the 1960s, Gentner helped scientific colleagues with establishing scientific institutions. With his knowledge of French science, Gentner helped Heinz Maier-Liebnitz with the establishment of the "Institut Laue-Langevin" in Grenoble. Gentner also helped Christoph Schmelzer establish the "Gesellschaft für Schwerionenforschungs" (GSI, Society for Heavy Ion Research), in Darmstadt. In 1968, in Florence, Gentner and Gilberto Bernardini founded of the European Physical Society. [ "How Darmstadt Became the Center of Heavy Ion Physics", "Gesellschaft für Schwerionenforschungs" ( [http://www.gsi.de/portrait/Broschueren/Wunderland/11_e.html GSI] , Society for Heavy Ion Research).] [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

During his career, Gentner demonstrated his interest in "Kosmochemie und Archäometrie" (cosmochemistry and archaeometry), which are fields at the intersection of cultural and natural sciences. [ Horst Wenninger "Bookshelf", "CERN Courier" ( [http://cerncourier.com/cws/article/cern/30155 Jun 4, 2007] ).]

Honors

Gentner was a member of many scientific academies and was awarded a number of honors: [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

*"Cothenius-Medaille in Gold" [1977] [ " [http://www.leopoldina-halle.de/cms/de/akademie/preise-und-auszeichnungen/cothenius-medaille.html Cothenius-Medaille] " – List of award recipients.] – " Deutschen Akademie der Naturforscher Leopoldina"

*"Ernst-Helmut-Vits-Preis"

*" Großen Verdienstkreuz mit Stern der Bundesrepublik Deutschland" (Great Cross of Merit of the Federal Republic of Germany)

*" Officier de la Legion d'Honneur" [1965] (Officer of the Legion of Honor, France)

*" Ordens Pour le merite für Wissenschaft und Künste "

*"Otto Hahn-Preis der Stadt Frankfurt" (Otto Hahn Prize of the City of Frankfurt)

*"Wolfgang Gentner Chair" established at the Weizmann Institute of Science, in Israel.

Personal

Gentner married Alice Pfaehler. They had a son Ralph and a daughter Doris. [ Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] ).]

Internal Reports

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. [ Hentschel and Hentschel, 1996, Appendix E; see the entry for "Kernphysikalische Forschungsberichte".] [ Walker, 1993, 268-274.]

*Walther Bothe and Wolfgang Gentner "Die Energie der Spaltungsneutronen aus Uran" G-17 (9 May 1940)

*Arnold Flammersfeld, Peter Jensen, Wolfgang Gentner "Die Energietönung der Uranspaltung" G-25 (21 May 1940)

*Arnold Flammersfeld, Peter Jensen, Wolfgang Gentner "Die Aufteilungsverhältnisse und Energietönung bei der Uranspaltung" G-26 (24 September 1940)

elected literature

*W. Bothe and W. Gentner "Herstellung neuer Isotope durch Kernphotoeffekt", "Die Naturwissenschaften" Volume 25, Issue 8, 126-126 (1937). Received 9 February 1937. Institutional affiliation: "Institut für Physik" at the "Kaiser-Wilhelm Institut für medizinische Forschung".

*W. Gentner "Kernphotoeffekt unter gleichzeitiger Aussendung von zwei Neutronen", "Die Naturwissenschaften" Volume 26, Number 7, 109-109 (1938). Received 8 February 1938. Institutional affiliation: "Institut für Physik" at the "Kaiser-Wilhelm Institut für medizinische Forschung".

*Woflgang Gentner "Mitteilungen aus der Kernphysik", "Die Naturwissenschaften" Volume 28, Number 25, 394-396 (1940). Institutional citation: Heidelberg.

Bibliography

*Beyerchen, Alan D. "Scientists Under Hitler: Politics and the Physics Community in the Third Reich" (Yale, 1977) ISBN 0-300-01830-4

*Citron, A "In Memoriam Wolfgang Gentner", "Physikalische Blätter" Volume 36, 358-359 (1980)

*Hoffmann, Dieter and Ulrich Schmidt-Rohr "Wolfgang Gentner: Festschrift zum 100. Geburtstag" (Springer, 2006)

*Hentschel, Klaus (editor) and Ann M. Hentschel (editorial assistant and translator) "Physics and National Socialism: An Anthology of Primary Sources" (Birkhäuser, 1996) ISBN 0-8176-5312-0

*Ulrich Schmidt-Rohr "Wolfgang Gentner: 1906-1980" ( [http://www.physik.uni-frankfurt.de/paf/paf181.html Universität Heidelberg] )

*Walker, Mark "German National Socialism and the Quest for Nuclear Power 1939–1949" (Cambridge, 1993) ISBN 0-521-43804-7

*Weiner, Charles "Oral history interview with Wolfgang Gentner" AIP Niels Bohr Library ( [http://libserv.aip.org:81/ipac20/ipac.jsp?uri=full=3100001~!5080!0&profile=newcustom-icos#focus 15 November 1971] )

Notes