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32.
The yields of neutrons from the reaction 25Mg(α, n)28Si and of γ-rays from the reaction 25Mg(α, nγ)28Si have been measured as a function of bombarding energy over the range 1.8–6.3 MeV, and the yield of neutrons from 26Mg(α, n)29Si has been measured over the range 1.8–6.0 MeV. Cross sections for 25, 26Mg(α, n)28, 29Si were extracted from the data and compared with global statistical-model calculations. The agreement is very good. Thermonuclear reaction rates under stellar conditions appropriate for explosive neon burning are calculated and their significance for the nucleosynthesis of rare neutron-rich nuclei is discussed. 相似文献
33.
K.A. Geoffroy J.B. Natowitz R. Eggers P. Kasiraj M.N. Namboodiri 《Nuclear Physics A》1978,302(1):333-342
The emission of prompt γ-radiation in the de-excitation of the products of the reactions of 120 MeV 20Ne with 27Al has been studied. Three NaI detectors placed at angles of 35°, 90° and 145° to the direction of the 20Ne beam were used to detect γ-rays in coincidence with reaction products having 6 ≦ Z ≦ 20, detected in a counter telescope. Data were obtained with the counter telescope in the same plane, as well as in a plane perpendicular to the plane defined by the beam and the NaI detectors. The average multiplicities 〈Mγ〉, average energies 〈Eγ〉, primary γ-ray energy spectra and the variation of 〈Mγ〉 and 〈Eγ〉 with angle of observation and kinetic energy of the detected products are presented and discussed in terms of the dominant reaction mechanisms. 相似文献
34.
The 93Nb(p, d)92Nb reaction was studied at a proton energy of 26.3 MeV. Angular distributions were obtained for outgoing deuterons to 37 states in 92Nb up to an excitation energy of 4.2 MeV. The results were compared with DWBA calculations to extract l-values and spectroscopic factors. Fourteen previously unobserved l = 1 transitions were measured. 相似文献
35.
Differential cross sections and asymmetries of 2.50 MeV polarized neutrons elastically scattered by In, Ho, Hg, Bi and U have been determined for scattering angles from 2.1° to 9.1°. The measurements were carried out by the use of a neutron positional spectrometer. The results, when compared with the predictions of the electromagnetic interaction, indicate some deviation of 〈σ(θ)P(θ)〉 from the expected values. The observed cross sections are systematically greater than those evaluated within the framework of the optical model. 相似文献
36.
37.
A. G. Artukh V. V. Avdeichikov J. Er G. F. Gridnev V. L. Mikheev V. V. Volkov J. Wilczynski 《Nuclear Physics A》1971,160(3):511-516
Multinucleon transfer reactions have been investigated by bombarding 232Th and 197Au targets with 137 MeV 16O ions. An exponential yield dependence on the Q-values was observed for nucleon exchange reactions. 相似文献
38.
From a measurement of the cross section for 12C(α, γ)16O at the Eα = 4.253±0.014 MeV(E = 10.352±0.011 MeV) resonance, the radiative width for the 10.35 MeV (Jπ = 4+) to 6.92 MeV (Jπ = 2+) transition was determined to be Γγ = 58±7 meV. This is somewhat higher than the value predicted by large j-j shell-model calculations, but agrees well with predictions based on the rotational and the SU(3) models for a 4p-4h band, and the deformed- basis calculation of Green and Brown. 相似文献
39.
F. de Oliveira Santos P. Himpe M. Lewitowicz I. Stefan N. Smirnova N. L. Achouri J. C. Angélique C. Angulo L. Axelsson D. Baiborodin F. Becker M. Bellegui E. Berthoumieux B. Blank C. Borcea A. Cassimi J. M. Daugas G. de France F. Dembinski C. E. Demonchy Z. Dlouhy P. Dolégiéviez C. Donzaud G. Georgiev L. Giot S. Grévy D. Guillemaud Mueller V. Lapoux E. Liénard M. J. Lopez Jimenez K. Markenroth I. Matea W. Mittig F. Negoita G. Neyens N. Orr F. Pougheon P. Roussel Chomaz M. G. Saint Laurent F. Sarazin H. Savajols M. Sawicka O. Sorlin M. Stanoiu C. Stodel G. Thiamova D. Verney A. C. C. Villari 《The European Physical Journal A - Hadrons and Nuclei》2005,24(2):237-247
The excitation function for the elastic-scattering reaction p( 18Ne, p) 18Ne was measured with the first radioactive beam from the SPIRAL facility at the GANIL laboratory and with a solid cryogenic hydrogen target. Several broad resonances have been observed, corresponding to new excited states in the unbound nucleus 19Na. In addition, two-proton emission events have been identified and are discussed. 相似文献
40.
T. Uesaka T. Wakui S. Sakaguchi T. Kawahara H. Sakai 《The European physical journal. Special topics》2007,150(1):71-74
We have constructed a polarized proton solid target system for
radioactive nuclear beam experiments at the Center for Nuclear Study,
the University of Tokyo. The proton polarization is based on an electron
population difference in a photo-excited triplet state of pentacene
molecule. The target system was completed in 2003 and applied to a
RI beam experiment in 2003 and 2005 by using the projectile fragment
separator, RIPS at RIKEN. The maximum polarization reached
20% under the condition of T=100 K and B=0.09 T.
Overview of the polarized target and its application in physics
experiments at RIPS and RIBF of RIKEN are presented. 相似文献