Search results for "decay [resonance]"
showing 10 items of 195 documents
Two-Proton Radioactivity ofKr67
2016
In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from 67Kr. At the same time, no evidence for 2p emission of 59Ge and 63Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to 67Kr as being the best new candidate among the three for two-proton radioactivity. 67Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of 67Kr is 7.4(30) ms.
Studies of Weak Beta-Delayed Protons Emitted in the Decay of Odd-Z, Tz = -3/2 Nuclei
1983
Radioactive decay of Tz = - 3/2 nuclides, 27P and 31Cl, predicted to be weak β-delayed proton precursors, have been looked for. Two proton groups having energies of 989 ± 15 and 1528 ± 20 keV and a half-life of 150 ± 25 ms were associated with the decay of 31Cl. The search for 27P is still under way, but the first qualitative results are briefly discussed.
Towards a determination of the chiral couplings at NLO in 1/N-C: L-8(r)(μ) and C-38(r)(μ)
2007
14 pages.-- ISI Article Identifier: 000244120200039.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0610290
Recent results in double beta decay
2015
Abstract Nuclear matrix elements for 0νββ, 0νhββ, and 2νββ decay in the microscopic interacting boson model (IBM-2) with isospin restoration are given for all nuclei of interest from 48Ca to 238U.
Alpha-Photon Coincidence Spectroscopy Along Element 115 Decay Chains
2014
Produced in the reaction 48Ca+243Am, thirty correlated α-decay chains were observed in an experiment conducted at the GSI Helmholzzentrum fur Schwerionenforschung, Darmstadt, Germany. The decay chains are basically consistent with previous findings and are considered to originate from isotopes of element 115 with mass numbers 287, 288, and 289. A set-up aiming specifically for high-resolution charged particle and photon coincidence spectroscopy was placed behind the gas-filled separator TASCA. For the first time, γ rays as well as X-ray candidates were observed in prompt coincidence with the α-decay chains of element 115.
ISOLTRAP Mass Measurements for Weak-Interaction Studies
2005
International audience; The conserved-vector-current (CVC) hypothesis of the weak interaction and the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix are two fundamental postulates of the Standard Model. While existing data on CVC supports vector current conservation, the unitarity test of the CKM matrix currently fails by more than two standard deviations. High-precision mass measurements performed with the ISOLTRAP experiment at ISOLDE/CERN provide crucial input for these fundamental studies by greatly improving our knowledge of the decay energy of super-allowed beta decays. Recent results of mass measurements on the beta emitters 18Ne, 22Mg, 34Ar, and 74Rb as pertaining to weak-i…
JYFLTRAP: a Penning trap for precision mass spectroscopy and isobaric purification
2012
In this article a comprehensive description and performance of the double Penning-trap setup JYFLTRAP will be detailed. The setup is designed for atomic mass measurements of both radioactive and stable ions and additionally serves as a very high-resolution mass separator. The setup is coupled to the IGISOL facility at the accelerator laboratory of the University of Jyväskylä. The trap has been online since 2003 and it was shut down in the summer of 2010 for relocation to the upgraded IGISOL facility. Numerous atomic mass and decay energy measurements have been performed using the time-of-flight ion-cyclotron resonance technique. The trap has also been used in several decay spectroscopy expe…
A method for fitting multi-component decay curves
1982
Abstract A generalization of a non-iterative method recently proposed by Mukoyama for the fitting of two-component decay curve is presented. Two modifications of the procedure are also suggested, by which the influence of the statistical fluctuations of the data may be reduced. Results of fairly good quality are obtained also for three- and, to a lesser extent, for four-component decay curves.
Low-energy couplings of QCD from topological zero-mode wave functions
2003
By matching 1/m^2 divergences in finite-volume two-point correlation functions of the scalar or pseudoscalar densities with those obtained in chiral perturbation theory, we derive a relation between the Dirac operator zero-mode eigenfunctions at fixed non-trivial topology and the low-energy constants of QCD. We investigate the feasibility of using this relation to extract the pion decay constant, by computing the zero-mode correlation functions on the lattice in the quenched approximation and comparing them with the corresponding expressions in quenched chiral perturbation theory.
Form-factors and current correlators: chiral couplingsL10r(μ) andC87r(μ) at NLO in 1/NC
2008
Using the resonance chiral theory Lagrangian, we perform a calculation of the vector and axial-vector two-point functions at the next-to-leading order (NLO) in the 1/N-C expansion. We have analyzed these correlators within the single-resonance approximation and have also investigated the corrections induced by a second multiplet of vector and axial-vector resonance states. Imposing the correct QCD short-distance constraints, one determines the difference of the two correlators Pi(t) equivalent to Pi(VV)(t)-Pi(AA)(t) in terms of the pion decay constant and resonance masses. Its low momentum expansion fixes then the low-energy chiral couplings L 1 0 and C 8 7 at NLO, keeping full control of t…