Search results for "superheavy element"
showing 10 items of 56 documents
Search for superheavy elements in monazites using chemical enrichment
1982
Evidence for the existence of superheavy elements in monazite inclusions embedded in Madagascan mica and surrounded by giant radioactive haloes was given by Gentry et al.1 who observed photons with energies corresponding to predicted Lα1 X-ray energies of element 126 (at 27.25 keV) and also of elements 116, 124 and 127 in irradiations of such crystals with collimated proton beams. For an unambiguous identification, the detection of further members of the L X-ray series would be most important. In X-ray spectra of monazite samples these transitions are buried under the strong K X-ray peaks of the lanthanide elements. They should, however, become visible after chemical enrichment of the super…
Recoil-α-fission and recoil-α–α-fission events observed in the reaction 48Ca + 243Am
2016
Products of the fusion-evaporation reaction 48Ca + 243Am were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated α-decay chains associated with the production of element Z=115, two recoil-α-fission and five recoil-α-α-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation ch…
A Progress Report on Laser Resonance Chromatography
2022
Atoms 10(3), 87 (2022). doi:10.3390/atoms10030087
Production and study of chemical properties of superheavy elements
2019
Abstract Some highlight examples on the study of production and chemical properties of heaviest elements carried out mostly at GSI Darmstadt are presented. They focus on the production of some of the heaviest known elements (114Fl, 115Mc, and 117Mc), studies of non-fusion reactions, and on chemical studies of 114Fl. This is the heaviest element, for which chemical studies have been performed to date.
Development of nuclear chemistry at Mainz and Darmstadt
2018
Abstract This review describes some key accomplishments of Günter Herrmann such as the establishment of the TRIGA Mark II research reactor at Mainz University, the identification of a large number of very neutron-rich fission products by fast, automated chemical separations, the study of their nuclear structure by spectroscopy with modern detection techniques, and the measurement of fission yields. After getting the nuclear chemistry group, the target laboratory, and the mass separator group established at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, a number of large international collaborations were organized exploring the mechanism of deeply inelastic multi-nucleon trans…
Superheavy-element research
1979
The existence of an island of relatively stable elements beyond the present Periodic Table has been predicted by theoretical extrapolations of nuclear properties. During the past 12 years vigorous efforts have been made to discover these superheavy elements in nature and to produce them by nuclear reactions.
Search for Superheavy Elements — A Status Report
1986
A survey is given of nuclear and chemical properties in the predicted island of spherical superheavy nuclei around element 114 and of recent attempts to produce such nuclei by transfer and fusion reactions.
From nuclear halos to superheavy nuclei—Perspectives for nuclear structure research at GSI
1998
Of fundamental interest is the investigation of nuclear matter at the limits of its existence in the vicinity of the driplines and in the region of the superheavy elements. The availability of unstable nuclei over large energy ranges and new experimental developments gave new impulse to nuclear structure research. Examples are the investigations of halo nuclei by nuclear decay studies combined with reactions at low and high energies, the mapping of the mass surface in large-scale direct mass measurements, and the production of heavy and superheavy nuclei. New developments such as high-current accelerators or the next generation of radioactive beam facilities will lead to further progress in…
Studying Chemical Properties of the Heaviest Elements: One Atom at a Time
2017
The search for heavier elements has been an exciting endeavor for nuclear scientists for many decades. This was invigorated after the first predictions that nuclear shell effects might render superheavy elements to have lifetimes long enough for their experimental study, or even their occurrence in Nature. A fascinating aspect concerns the question of their chemical properties: will they conform to the well-established structure of the Periodic Table of the Elements, or will so-called relativistic effects—a result of the high velocities of electrons in the vicinity of highly-charged nuclei—lead to dramatic deviations? Chemical studies of the heaviest elements are complicated by small produc…
Search for long-lived superheavy elements in the reaction of136Xe with238U
1978
A search with radiochemical methods for long-lived superheavy elements in 238U targets bombarded with intense beams of136Xe ions produced negative results. A formation cross section of ≤1×10−35 cm2 is deduced at 95% confidence level for nuclides with half-lives between 1 and 200 d.