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The article focuses on the history of the development of the theory of nuclear fission. It chronicles the creation of the theory at the Kaiser Wilhelm Institute for Chemistry in Berlin, Germany in December 1938 through the collaboration of chemists Otto Hahn, Fritz Strassmann, and physicist Lisa Meitner. It also mentions the significant evolution of the theory in which its founders claim that it belonged to the field of chemistry.

After the disaster of Fukushima in March 2011, some countries and especially Germany changed their energy policy dramatically in order to end the use of nuclear fission in energy production. This has stirred interest in many countries. In this article the developments in Germany are considered against the historical and legal background. First, the article traces the different phases in the use of nuclear energy. As a second step it tries to find an explanation for why the nuclear exit occurred. Thirdly, it analyses the role of regulatory and constitutional law in the introduction and phasing out of nuclear energy use. Finally, some general conclusions are drawn on the advantages and drawbacks of nuclear energy and on lessons to be learned for socio-legal theory. [ABSTRACT FROM PUBLISHER]

The article offers an overview of the historic debate of nuclear power in Germany. It demonstrates how the relationship between Germans and nuclear technology have changed since Otto Hahn and Fritz Strassmann, in December 1938 first demonstrated nuclear fission in Berlin. It explores the plan of German government to implement the nuclear phase-out

One of the longstanding attractions of the Deutsches Museum in Munich, Germany, has been its display of the apparatus associated with the discovery of nuclear fission. Although the discovery involved three scientists, Otto Hahn, Lise Meitner, and Fritz Strassmann, the fission display was designated for over 30 years as the Arbeitstisch von Otto Hahn (Otto Hahn’s Worktable), with Strassmann mentioned peripherally and Meitner not at all, and it was not until the early 1990s that the display was revised to include all three codiscoverers more equitably. I examine the creation of the fission display in the context of the postwar German culture of silencing the National Socialist past, and trace the eventual transformation of the display into a contemporary exhibit that more accurately represents the scientific history of the fission discovery. [ABSTRACT FROM AUTHOR]

- 40Ar/39Ar dating of recrystallized K-feldspar melt particles separated from partially molten biotite granite in impact melt rocks from the approximately 24 km Nördlinger Ries crater (southern Germany) yielded a plateau age of 14.37 ± 0.30 (0.32) Ma (2σ). This new age for the Nördlinger Ries is the first age obtained from (1) monomineralic melt (2) separated from an impact-metamorphosed target rock clast within (3) Ries melt rocks and therewith extends the extensive isotopic age data set for this long time studied impact structure. The new age goes very well with the 40Ar/39Ar step-heating and laser probe dating results achieved from mixed-glass samples (suevite glass and tektites) and is slightly younger than the previously obtained fission track and K/Ar and ages of about 15 Ma, as well as the K/Ar and 40Ar/39Ar age data obtained in the early 1990s. Taking all the 40Ar/39Ar age data obtained from Ries impact melt lithologies into account (data from the literature and this study), we suggest an age of 14.59 ± 0.20 Ma (2σ) as best value for the Ries impact event. [ABSTRACT FROM AUTHOR]

A novel experimental approach for studying dissipative effects in nuclear fission has been developed at GSI, Darmstadt. Fragmentation of radioactive heavy-ion beams is employed to prepare fissile nuclei in well-defined initial conditions and the fission-fragment nuclear charge distribution is used for investigating pre-saddle dynamics in detail. The undeniable manifestation of transient effects at high temperature is demonstrated and the influence of the initial deformation is clearly evidenced for the first time. [ABSTRACT FROM AUTHOR]

A novel experimental program aiming to study the properties of fragments and neutrons emitted in the fission process has been initiated. The experiment will be held at the ELISe electron-ion collider to be constructed at GSI, Darmstadt in the framework of the FAIR extension of the facility. The experiment will take advantage of the inverse kinematics allowing, in particular, a total mass and charge resolution for all fission fragments. [ABSTRACT FROM AUTHOR]

Discusses the mystery of whether or not Werner Heisenberg gave Niels Bohr a drawing that Bohr came to believe was that of a German nuclear weapon. Anecdote told by physicist Hans Bethe on the visit wherein Heisenberg gave Bohr the drawing; Text of the letter written by Robert Oppenheimer to General Leslie Groves, dated January 1, 1944, regarding the original drawing.

The article presents science news briefs as of April 23, 2015. Germany's ruling political parties have agreed to increase funding for science by €5 billion between 2018-2018. The journal "Meccanica" has retracted 11 papers authored by engineer Alberto Carpinteri over a conflict of interests stemming from Carpinteri's views on nuclear fission. Mexican President Enrique Peña announced a plan to save the vaquita, an endangered species of porpoise.

Abstract: Based on 15 years of experience with neutron therapy at the former facility at Munich research reactor FRM, fast neutron therapy with fission neutrons of FRM II is performed at the new facility MedApp since June 2007. General indications are superficially located tumors with insufficient response to conventional radiotherapy. Until August 2009, 58 patients were treated, 25% of them with curative intention (adenoid cystic carcinoma of major salivary glands, malignant melanoma, sarcoma). The most frequent palliative indications were breast wall recurrences of breast cancer and skin or lymph node recurrences of squamous cell carcinomas, resulting in response rates of 84% and 42%, respectively. Short treatment times of fast neutron therapy (3–5 fractions in 2–3 weeks) are advantageous in palliative treatment strategies. [ABSTRACT FROM AUTHOR]

The article profiles physicist Lise Meitner. Meitner was one of the first women to attend a university in Vienna. She studied physics under physicist Ludwig Boltzmann and attended the University of Berlin, where she met chemist Otto Hahn. She became the first German female professor and studied radioactive particles with Hahn. Meitner was forced to leave German for Holland after the Nazis came to power. Hahn later downplayed Meitner's involvement in nuclear fission.

The article discusses the forensic analysis of 1940s German uranium in order to discover its place of origin through referencing a study coauthored by the scientist Maria Wallenius published in the journal "Angewandte Chemie International Edition" ("Angew. Chem. Int. Ed.") in 2015, including in regard to the inability 1940s German uranium experiments to sustain nuclear fission.

Purpose: At the new research reactor FRM II of the Technical University of Munich (TUM), the facility for Medical Applications (MEDAPP) was installed where fast neutrons are available as a beam for medical use., Material and Methods: Thermal neutrons induce fission in a pair of uranium converter plates and generate fast neutrons which are guided to the patient by a beam tube. The maximum opening of the multi leaf collimator (MLC) is 30x20 cm2 WxH. The beam is characterized by neutron-photon mixed beam phantom dosimetry. Specific safety measures are outlined., Results: The neutron and gamma dose rates are 0.52 Gy/min and 0.20 Gy/min, respectively, in 2 cm depth of a water phantom. The half maximum depth of the neutron dose rate in water is 5.4 cm (mean neutron energy 1.9+/-0.1 MeV). Conformity with the European Medical Devices Directive (MDD) 93/42/EEG, was proven so that MEDAPP has a CE mark and since February 2007 also the license for clinical operation., Conclusion: The clinical neutron irradiations of malignant tumors, which were performed at the former research reactor FRM until 2000, can be continued at FRM II under improved conditions. First patients were irradiated in June 2007.

GSI is operating a facility for the production of rare isotopes. Nuclei are produced by fragmentation or fission of the impinging heavy ions with energies of approximately 1 GeV per nucleon. The major part of the primary beam and the produced nuclei is deposited in the components of the Fragment Separator (FRS) and generates neutron radiation. Thermoluminescence dosemeters (TLDs) (6LiF/7LiF pairs in PE spheres) were exposed in neutron fields produced by uranium beams with energies between 100 and 1000 MeV per nucleon during an irradiation period in the year 2002. Two-dimensional dose distributions are obtained using these TL measurements in combination with model calculations. The applied model describes the dose distribution as a superposition of dose patterns of 20 single sources equally distributed along the FRS. The single source distribution is based on a measured double differential neutron distribution for a 1 GeV per nucleon uranium beam.

A small number of animal thyroids from Bad Hall, Austria; Ulm, Germany; and Steinkjer, Norway had 131I (half-life 8.06 d) measured between 21 and 72 d following the nuclear accident at Chernobyl on 26 April 1986. Nine years later 129I (half-life 1.57 x 10(7) y) fission product and natural 127I were measured in the same thyroids. The mass ratios, 129I/131I were calculated to the date of the Chernobyl accident and they ranged between 13 and 71. These ratios are compared to the expected ratios within an operating nuclear reactor during 2 y of operation, where the 129I/131I(-1) ratio never exceeded 30. The observed ratio of 129I to natural 127I in thyroids ranged from 5 to 200 times the ratio before the accident, except that the Norwegian thyroids had 129I/127I ratios which were less than the ratios of pre-Chernobyl thyroids from Ulm. These studies show the 129I and 131I from the Chernobyl accident were accumulated with natural 127I in animal thyroids but the isotope ratios, calculated to the release date, had wide ranges. The 131I radioactive exposure might be estimated from a fission product mixture by measuring 129I in thyroids long after the exposure to 131I, but the results would probably show a wide range of possibilities. The determining variables should be evaluated. We know of no previous data regarding both 131I and 129I in thyroid glands during the first 3 mo after the Chernobyl accident.