993 resultados para LI-7(N,GAMMA)LI-8


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We present a direct measurement of the low-energy Li-8(p, alpha)He-5 cross section, using a radioactive Li-8 beam impinging on a thick target. With four beam energies, we cover the energy range between E-c.m. = 0.2 and 2.1 MeV. An R-matrix analysis of the data is performed and suggests the existence of two broad overlapping resonances (5/2(+) at E-c.m. = 1.69 MeV and 7/2(+) at E-c.m. = 1.76 MeV). At low energies our data are sensitive to the properties of a subthreshold state (E-x = 16.67 MeV) and of two resonances above threshold. These resonances were observed in previous experiments. The R-matrix fit confirms spin assignments, and provides partial widths. We propose a new Li-8(p, alpha)He-5 reaction rate and briefly discuss its influence in nuclear astrophysics. DOI: 10.1103/PhysRevC.86.064321

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Signed, p.21: E. Card. Consalvi.

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A new measurement of proton resonance scattering on Be-7 was performed tip to the center-of-mass energy of 6.7 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study of the University of Tokyo. The excitation function of Be-7 + p elastic scattering above 3.5 MeV was measured Successfully for the first time, providing important information about the resonance structure of the B-8 nucleus. The resonances are related to the reaction rate of Be-7(p.gamma)B-8. which is the key reaction in solar B-8 neutrino production. Evidence for the presence of two negative parity states is presented. One of them is a 2(-) state observed as a broad s-wave resonance, the existence of which had been questionable. Its possible effects on the determination of the astrophysical S-factor of Be-7(p.gamma)B-8 at solar energy are discussed. The other state had not been observed in previous measurements, and its spin and parity were determined as 1(-). (C) 2009 Elsevier B.V. All rights reserved.

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The reaction of the title complexes (FIG. 1) with N-bromosuccinimide or bromine in chloroform yields isomeric bromo complexes on substitution of the γ-CH carbon proton by bromine. The brominated products have been characterised by ir, pmr, electronic absorption spectra, conductivity and magnetic susceptibility measurements. The linkage isomerisation of the brominated products in chloroform has been shown to depend on the diamine residue.

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This report gives a summary of common pleas cases broken down by county and circuit as of August 31, 2014.

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This gives the criminal records summary of activity by circuit/county for period 7/1/2014 thru 8/31/2014.