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111.
T. Zerguerras B. Blank Y. Blumenfeld T. Suomijärvi D. Beaumel B. A. Brown M. Chartier M. Fallot J. Giovinazzo C. Jouanne V. Lapoux I. Lhenry-Yvon W. Mittig P. Roussel-Chomaz H. Savajols J. A. Scarpaci A. Shrivastava M. Thoennessen 《The European Physical Journal A - Hadrons and Nuclei》2004,20(3):389-396
Light proton-rich bound and unbound nuclei were produced by means of stripping reactions of secondary beams of 20Mg and 18Ne. The decays of the unbound nuclei 18,19Na have been measured by detecting their decay products 17,18Ne and one proton and by performing an invariant-mass reconstruction. For 18Na, the present work is the first measurement of its decay. As the decay scheme of this nucleus could not be determined, two possible scenarios are proposed and discussed. In addition, the decay of excited states in 17Ne via two-proton emission was observed. The proton-proton angular distribution is isotropic for the first two-proton-emitting states, whereas higher-lying states seem to decay by a correlated two-proton emission, consistent with a 2He emission pattern for part of the decay strength.Received: 30 September 2003, Revised: 27 November 2003, Published online: 2 June 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 23.40.-s
decay; double
decay; electron and muon capture - 23.50. + z Decay by proton emissionM. Chartier: Present address: Physics Department, University of Liverpool, Liverpool, UK.M. Fallot: Present address: SUBATECH, Ecole des Mines, BP 20722, F-44307 Nantes Cedex, France.A. Shrivastava: Permanent address: Bhabha Atomic Research Center, Mumbai, India.Experiment performed at the GANIL facility, Caen, France. 相似文献
112.
Mechanoluminescence spectra of triglycine sulfate, guanidine aluminium sulfate, rochelle salt, diglycine manganous chloride
dihydrate, lithium ammonium tartate monohydrate and potassium dihydrogen phosphate crystals resemble the discharge spectra
of nitrogen gases. Glycine silver nitrate, thiourea, ammonium sulfate and azobenzene crystals, the structure of which is centrosymmetric
at room temperature, do not show mechanoluminescence. Following the role of crystal structure, the mechanoluminescence excitation
is discussed on the basis of the piezo-electrification of the new surfaces created during fracture of the crystals. 相似文献
113.
The electron paramagnetic resonance of Mn2+ in KNO3 single crystal is investigated over a temperature cycle through transition temperatures. The hyperfine coupling constant, A, half width,Δ H, and the line intensity, I, are found to show sudden changes at the transition temperature, at whichα-KNO3 changes intoβ-KNO3. The lines are much sharper in the high temperatureβ-phase than inα-phase of the crystal. They are explained, qualitatively, in terms of structure change and rotation of NO 3 ? ions. The spectra in the two phases,α andβ, are analysed in terms of usual spin-Hamiltonian. A search of metastableγ-phase is also made and probable indications for the same are found. 相似文献
114.
The core and overlap contributions to the electronic charge density at the 107Ag nucleus in AgF and AgCl lattices are calculated as a function of the interatomic distance. 相似文献
115.
Using Bohm and Pines theory of plasma oscillations in solids the relative intensities of the Mg KVβ and Al KVIβ satellites have been estimated as 0.89% and 0.61% respectively. These values are in close agreement with the experimental values reported by Kunzl. 相似文献
116.
K.N. Shrivastava 《Chemical physics letters》1973,19(3):404-405
There is a new contribution to the curvature of energy levels as a function of the strength of the crystal field. Thus the levels which are flat in the Orgel—Tanabe—Sugano diagrams, in fact, have non-zero curvature and the accidential degeneracies are removed. 相似文献
117.
118.
K. N. Shrivastava 《Physics letters. A》1979,70(5-6):483-484
The electronic charge density at 129I- is calculated from the Hartree-Fock wave functions in the lithium iodide lattice and from that it is found that the charge density varies approximately as the inverse seventh power of the interatomic distance. 相似文献
119.
120.
Keshav N. Shrivastava 《Physics letters. A》1978,66(4):325-328
The self energy of a uniform magnon due to splitting into two magnons of oppositely directed momenta is calculated in the presence of a magnon-photon interaction, and it is found that the magnons and the photons form excitations of mixed character. Thus there is a net correction to the magnon splitting due to an interference. 相似文献