Search results for "[formula omitted] decay"
showing 10 items of 1452 documents
Quantum-state-selective decay spectroscopy of 213Ra
2017
An experimental scheme combining the mass resolving power of a Penning trap with contemporary decay spectroscopy has been established at GSI Darmstadt. The Universal Linear Accelerator (UNILAC) at GSI Darmstadt provided a 48Ca beam impinging on a thin 170Er target foil. Subsequent to velocity filtering of reaction products in the Separator for Heavy Ion reaction Products (SHIP), the nuclear ground state of the 5n evaporation channel 213Ra was mass-selected in SHIPTRAP, and the 213Ra ions were finally transferred into an array of silicon strip detectors surrounded by large composite germanium detectors. Based on comprehensive geant4 simulations and supported by theoretical calculations, the …
117番元素Ts合成のための48Ca+249Bk融合反応
2019
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.
Positron Studies of Subsurface Zone in Titanium Created in Sliding Wear
2014
Positron annihilation studies of the subsurface zone constituted during dry sliding in pure titanium are reported. A new type of defect depth profile in this zone, which is not an exponential decay usually reported for other metals and alloys, is observed. Two layers in the subsurface zone are present in this metal. In the layer adjacent to the worn surface, the characteristic plateau of the mean positron lifetime that extends to a depth of 60–70 μm was observed. Small vacancy clusters and dislocations were recognized in this layer. At deeper zone, the mean positron lifetime decreased exponentially in the manner typical for the other metals. In this zone, vacancy clusters increase in size a…
Temporal loudness weights in background noise: Data and models
2019
Previous studies consistently showed that human listeners primarily consider the beginning of a time-varying sound when judging its overall loudness, and place less weight on subsequent temporal portions. However, all experiments studying this primacy effect in temporal loudness weights presented the target sound in quiet. Here, we compared temporal weights when the target sound was either presented in quiet or in a continuous background noise, and for a variation in the level of the target sound across a range of 60 dB. The target sound was a time-varying narrowband noise, the background noise was a continuous bandpass-filtered noise. In all conditions, we observed the expected primacy eff…
Review of Particle Physics
2020
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, …
Vesiclepedia:A Compendium for Extracellular Vesicles with Continuous Community Annotation
2012
Vesiclepedia is a community-annotated compendium of molecular data on extracellular vesicles.
Theoretical study of neutrino scattering off the stable even Mo isotopes at low and intermediate energies
2011
A systematic study of the cross sections of neutral-current neutrino scattering off the stable even Mo isotopes (mass number A = 92, 94, 96, 98, 100), at low and intermediate neutrino energies (E(nu) <= 130 MeV), is presented and discussed. The required wave functions for the initial (ground state) and all accessible final nuclear states are constructed in the context of the quasi-particle random-phase approximation (QRPA) and tested against data on the low-lying energy spectra of the isotopes in question. The individual contributions coming from the polar-vector and axial-vector components of the hadronic current for the coherent and incoherent channels of each isotope are investigated. Th…
Beta-Decay Half-Lives and Neutron-Emission Probabilities of Very Neutron-Rich Y to Tc Isotopes
1996
Neutron-rich {sub 39}Y to {sub 43}Tc isotopes have been produced by fission of uranium with a 50MeV H{sub 2}{sup +} beam. Beta-decay half-lives, delayed neutron-emission probabilities, and production yields have been measured and compared with theory. Beta decay of 4 new isotopes is reported, and the {beta}-delayed neutron-emission mode has been discovered for 12 isotopes of the elements niobium and technetium. The results compared to quasiparticle random phase approximation predictions indicate the increasing importance of fast {beta} transitions to high-lying states of nuclei with large neutron excess. {copyright} {ital 1996 The American Physical Society.}
Stability of the heaviest elements : K isomer in 250No
2020
Decay spectroscopy of 250No has been performed using digital electronics and pulse-shape analysis of the fast nuclear decays for the first time. Previous studies of 250No reported two distinct fission decay lifetimes, related to the direct fission of the ground state and to the decay of an isomeric state but without the possibility to determine if the isomeric state decayed directly via fission or via internal electromagnetic transitions to the ground state. The data obtained in the current experiment allowed the puzzle to finally be resolved, attributing the shorter half-life of t1/2 = 3.8 ± 0.3 μs to the ground state and the longer half-life t1/2 = 34.9+3.9 −3.2 μs to the decay of an isom…
Excited levels in the multishaped 117Pd nucleus studied via β decay of 117Rh
2018
Monoisotopic samples of exotic, neutron-rich 117Rh nuclei, produced in the proton-induced fission of 238U and separated using the IGISOL mass separator coupled to the JYFLTRAP Penning trap, were used to perform β and γ coincidence spectroscopy of 117Pd. The spin parity of the ground state of 117Pd was determined to be 1/2+ and the 19.1 ms isomer at 203.2 keV was assigned a spin-parity 7/2−. The 117Rh β−-decay scheme was considerably extended, and various sequences of the levels were interpreted as resulting from the prolate, oblate, and triaxial nuclear shapes. Some of the β− decays were considered as the allowed Gamow-Teller transitions. The experimental distribution of Gamow-Teller streng…