0000000001289911
AUTHOR
M. Block
Spectroscopy along flerovium decay chains. II : Fine structure in odd-A289Fl
Fifteen correlated α-decay chains starting from the odd-A superheavy nucleus 289Fl were observed following the fusion-evaporation reaction 48Ca+244Pu. The results call for at least two parallel α-decay sequences starting from at least two different states of 289Fl. This implies that close-lying levels in nuclei along these chains have quite different spin-parity assignments. Further, observed α-electron and α-photon coincidences, as well as the α-decay fine structure along the decay chains, suggest a change in the ground-state spin assignment between 285Cn and 281Ds. Our experimental results, on the excited level structure of the heaviest odd-N nuclei to date, provide a direct testing groun…
Towards saturation of the electron-capture delayed fission probability : The new isotopes 240Es and 236Bk
The new neutron-deficient nuclei 240Es and 236Bk were synthesised at the gas-filled recoil separator RITU. They were identified by their radioactive decay chains starting from 240Es produced in the fusion–evaporation reaction 209Bi(34S,3n)240Es. Half-lives of 6(2) sand 22+13−6swere obtained for 240Es and 236Bk, respectively. Two groups of αparticles with energies Eα=8.19(3) MeVand 8.09(3) MeVwere unambiguously assigned to 240Es. Electron-capture delayed fission branches with probabilities of 0.16(6)and 0.04(2)were measured for 240Es and 236Bk, respectively. These new data show a continuation of the exponential increase of ECDF probabilities in more neutron-deficient isotopes. peerReviewed
Some Remarks on the Discovery of 244Md
In two recent papers by Pore et al. and Khuyagbaatar et al., discovery of the new isotope Md244 was reported. The decay data, however, are conflicting. While Pore et al. report two isomeric states decaying by α emission with Eα(1)=8.66(2) MeV, T1/2(1)=0.4-0.1+0.4 s and Eα(2)=8.31(2) MeV, T1/2(2)≈6 s, Khuyagbaatar et al. [Phys. Rev. Lett. 125, 142504 (2020).PRLTAO0031-900710.1103/PhysRevLett.125.142504] report only a single transition with a broad energy distribution of Eα=(8.73-8.86) MeV and T1/2=0.30-0.09+0.19 s. The data published in Pore et al. are very similar to those published for Md245m [Eα=8.64(2), 8.68(2) MeV, T1/2=0.35-0.16+0.23 s [V. Ninov, F. P. Heßberger, S. Hofmann, H. Folger,…
First Study on Nihonium (Nh, Element 113) Chemistry at TASCA
Frontiers in Chemistry 9, 753738 (2021). doi:10.3389/fchem.2021.753738
VADER: A novel decay station for actinide spectroscopy
Nuclear instruments & methods in physics research / B 540, 148 - 150 (2023). doi:10.1016/j.nimb.2023.04.021
Impact of clinical phenotypes on management and outcomes in European atrial fibrillation patients: a report from the ESC-EHRA EURObservational Research Programme in AF (EORP-AF) General Long-Term Registry
Abstract Background Epidemiological studies in atrial fibrillation (AF) illustrate that clinical complexity increase the risk of major adverse outcomes. We aimed to describe European AF patients’ clinical phenotypes and analyse the differential clinical course. Methods We performed a hierarchical cluster analysis based on Ward’s Method and Squared Euclidean Distance using 22 clinical binary variables, identifying the optimal number of clusters. We investigated differences in clinical management, use of healthcare resources and outcomes in a cohort of European AF patients from a Europe-wide observational registry. Results A total of 9363 were available for this analysis. We identified three …
Spectroscopy along flerovium decay chains. III : Details on experiment, analysis, 282Cn, and spontaneous fission branches
Flerovium isotopes (element Z=114) were produced in the fusion-evaporation reactions 48Ca+242,244Pu and studied with an upgraded TASISpec decay station placed in the focal plane of the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Twenty-nine flerovium decay chains were identified by means of correlated implantation, α decay, and spontaneous fission events. Data analysis aspects and statistical assessments, primarily based on measured rates of various events, which laid the foundation for the comprehensive spectroscopic information on the flerovium decay chains, are presented in detail. Various decay scenarios of an excited state obse…
On the adsorption and reactivity of element 114, flerovium
Flerovium (Fl, element 114) is the heaviest element chemically studied so far. To date, its interaction with gold was investigated in two gas-solid chromatography experiments, which reported two different types of interaction, however, each based on the level of a few registered atoms only. Whereas noble-gas-like properties were suggested from the first experiment, the second one pointed at a volatile-metal-like character. Here, we present further experimental data on adsorption studies of Fl on silicon oxide and gold surfaces, accounting for the inhomogeneous nature of the surface, as it was used in the experiment and analyzed as part of the reported studies. We confirm that Fl is highly v…
Recoil-alpha-fission and Recoil-alpha-alpha-fission Chains Stemming from Element 115
GSI Scientific Report 2014 - GSI Report 2015-1
Study of non-fusion products in the 50Ti + 249Cf reaction
Physics letters / B B 784, 199 - 205 (2018). doi:10.1016/j.physletb.2018.07.058
Spectroscopic Tools Applied to Element Z = 115 Decay Chains
Nuclides that are considered to be isotopes of element Z = 115 were produced in the reaction 48Ca + 243Am at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt. The detector setup TASISpec was used. It was mounted behind the gas-filled separator TASCA. Thirty correlated α-decay chains were found, and the energies of the particles were determined with high precision. Two important spectroscopic aspects of the offline data analysis are discussed in detail: the handling of digitized preamplified signals from the silicon strip detectors, and the energy reconstruction of particles escaping to upstream detectors relying on pixel-by-pixel dead-layer thicknesses.
117番元素Ts合成のための48Ca+249Bk融合反応
We have performed an experiment to synthesize the element 117 (Ts) with the $^{48}$Ca+$^{249}$Bk fusion reaction. Four $\alpha$-decay chains attributed to the element 117 were observed. Two of them were long decay chains which can be assigned to the one originating from the $\alpha$ decay of $^{294}$Ts. The other two were short decay chains which are consistent with the one originating from the $\alpha$ decay of $^{293}$Ts. We have compared the present results with the literature data, and found that our present results mostly confirmed the literature data, leading to the firm confirmation of the synthesis of the element 117.