8,265 research outputs found

    Coherent Description for Hitherto Unexplained Radioactivities by Super- and Hyperdeformed Isomeric States

    Full text link
    Recently long-lived high spin super- and hyperdeformed isomeric states with unusual radioactive decay properties have been discovered. Based on these newly observed modes of radioactive decay, consistent interpretations are suggested for previously unexplained phenomena seen in nature. These are the Po halos, the low-energy enhanced 4.5 MeV alpha-particle group proposed to be due to an isotope of a superheavy element with Z = 108, and the giant halos.Comment: 8 pages, 2 figures, 1 table, to be published in Int. J. Mod. Phys.

    Super- and Hyperdeformed Isomeric States and Long-Lived Superheavy Elements

    Full text link
    The recent discoveries of the long-lived high spin super- and hyperdeformed isomeric states and their unusual radioactive decay properties are described. Based on their existence a consistent interpretation is given to the production of the long-lived superheavy element with Z = 112, via secondary reactions in CERN W targets, and to the low energy and very enhanced alpha-particle groups seen in various actinide fractions separated from the same W target. In addition, consistent interpretations are suggested for previously unexplained phenomena seen in nature. These are the Po halos, the low-energy enhanced 4.5 MeV alpha-particle group proposed to be due to an isotope of a superheavy element with Z = 108, and the giant halos.Comment: 4 pages. Contribution to the 2nd Int. Conf. on the Chemistry and Physics of the Transactinide Elements (TAN 03) Napa California, November 200

    Evidence for a long-lived superheavy nucleus with atomic mass number A=292 and atomic number Z=~122 in natural Th

    Full text link
    Evidence for the existence of a superheavy nucleus with atomic mass number A=292 and abundance (1-10)x10^(-12) relative to 232Th has been found in a study of natural Th using inductively coupled plasma-sector field mass spectrometry. The measured mass matches the predictions [1,2] for the mass of an isotope with atomic number Z=122 or a nearby element. Its estimated half-life of t1/2 >= 10^8 y suggests that a long-lived isomeric state exists in this isotope. The possibility that it might belong to a new class of long-lived high spin super- and hyperdeformed isomeric states is discussed.[3-6]Comment: 14 pages, 5 figure

    Decolonizing the Curriculum and the University:A Panel Discussion with Rolando Vasquez, Layal Ftouni and Toni Pape, 31 March 2021

    Get PDF
    This panel was made possible by the collaborative efforts of editors of Junctions and an intern from Transmission in Motion, both spaces being initiatives by Utrecht University. While emerging from independent curiosities around decolonial thought and practice, specifically related to the movement in the educational sector (more commonly recognised as Decolonizing the Curriculum, a subset of Decolonizing the University movement) this collaborative panel aims to have as starting point the ideology, better articulated Walter D. Mignolo and Catherine E. Walsh, as a relational practise which requires the recognition of one’s position as their entry point. In their words (2018), decolonial thinking and practice embodies (or should embody) situatedness, “…the ways that different local histories and embodied conceptions and practices of decoloniality, including our own, can enter into conversations and build understandings that both cross geopolitical locations and colonial differences and contest the totalizing claims and political-epistemic violence of modernity” (Walsh and Mignolo 2018, 1). We understand this as a way to contextualise decolonial theory and practice within educational spaces in the Netherlands, so as not to risk transforming it into an empty metaphor. To contextualise theory and practice also requires an understanding of how Decolonial Work is spoken about and practised in specific institutional spaces. With that in mind, we invited Layal Ftouni, Toni Pape and Rolando Vazquez Melken to discuss the limits of what we allow ourselves to think, talk, imagine, make and do in relation to the discourse of decolonization

    Existence of long-lived isotopes of a superheavy element in natural Au

    Get PDF
    Evidence for the existence of long-lived isotopes with atomic mass numbers 261 and 265 and abundance of (1-10)x1010^{-10} relative to Au has been found in a study of natural Au using an inductively coupled plasma - sector field mass spectrometer. The measured masses fit the predictions made for the masses of 261^{261}Rg and 265^{265}Rg (Z=111) and for some isotopes of nearby elements. The possibility that these isotopes belong to the recently discovered class of long-lived high spin super- and hyperdeformed isomeric states is discussed.Comment: 4 pages, 3 figures, 2 table

    ICP-SFMS search for long-lived naturally-occurring heavy, superheavy and superactinide nuclei compared to AMS experiments

    Full text link
    Negative results obtained in AMS searches by Dellinger et al. on mostly unrefined ores have led them to conclude that the very heavy long-lived species found in chemically processed samples with ICP-SFMS by Marinov et al. are artifacts. We argue that it may not be surprising that results obtained from small random samplings of inhomogeneous natural minerals would contrast with concentrations found in homogeneous materials extracted from large quantities of ore. We also point out that it is possible that the groups of counts at masses 296 and 294 seen by Dellinger et al. could be, within experimental uncertainties, due to 296^{296}Rg and 294^{294}eka-Bi in long-lived isomeric states. In such case, the experiments of Dellinger et al. lend support to the experiments of Marinov et al.Comment: 2 pages. Accepted for publication in Int. J. Mod. Phys.
    corecore