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91.
R.E. Warner R.L. Ruyle W.G. Davies G.C. Ball A.J. Ferguson J.S. Forster 《Nuclear Physics A》1975,255(1):95-108
The predictions of two fully antisymmetrized reaction theories (DWBA and PWBA-FSI) are compared with absolute coincidence cross sections for the 2H(3He, 3He p)n and 2H(3He, 3H p)p reactions exhibiting final-state interactions (FSI) and quasi-elastic scattering (QES) both with and without charge exchange. The DWBA theory takes into account both the initial 3He-d and the final N-N interactions, while the PWBA-FSI theory includes only the latter. New QES data at EHe = 35.9 MeV, as well as previously reported 26.8 and 35.9 MeV data, are fitted. The DWBA theory gives good fits, both in shape and magnitude, to spectra showing N-N final-state interactions but gives somewhat poorer fits to QES spectra whose predicted magnitudes are two to ten times too large. The PWBA-FSI theory always predicts cross sections that are too large; however the predicted shapes are about as good as those from the DWBA. The initial-state interaction is shown to affect both the width and position of QES peaks from these reactions. 相似文献
92.
G.C. Ball T.K. Alexander W.G. Davies J.S. Forster I.V. Mitchell J. Keinonen H.B. Mak 《Nuclear Physics A》1982,386(2):333-345
Mean lifetimes of levels in 18F have been measured using the Doppler-shift attenuation method and the inverse reaction 3He(16O, p)18F. Targets of 3He implanted into Al, Nb, and Au foils were employed in the measurements. The Doppler-broadened lineshapes observed at 0° to the beam were analyzed to obtain the following lifetime values: 0.971 ± 0.030, 0.605 ± 0.029 and 0.435 ± 0.041 ps for the 1.70(1+), 2.52(2+) and 3.36(3+)MeV members of the Kπ = 1+ rotational band, 5.12 ± 0.56, 0.403 ± 0.018 and 1.91 ± 0.17 ps for the 2.10(2?), 3.13(1?) and 3.79(3?) MeV members of the Kπ = 0? bands, and 〈1.2, 2.7+4.1?2.7 and 20 ± 2 fs for the 3.06(2+, T = 1), 3.72(1+) and 3.84(2+) MeV states, respectively. 相似文献
93.
D. Aston M. Atkinson R. Bailey A.H. Ball B. Bouquet G.R. Brookes J. Br?ring P.J. Bussey D. Clarke A.B. Clegg B. DAlmagne G. De Rosny B. Diekmann A. Donnachie M. Draper B. Drevillon I.P. Duerdoth J.-P. Dufey T.P. Yiou 《Physics letters. [Part B]》1981,104(3):231-234
The reaction γp → K+K? p has been investigated with tagged photons in the energy range of 20 < Eγ < 70 GeV. A structure in the 1.7 GeV mass region is observed and interpreted in terms of a recurrence of the ø. 相似文献
94.
We show, numerically, that the integral equation for the axial gauge gluon propagator developed in the preceding paper has an explicit solution with the features outlined there. This solution is expected to be exact in the infrared limit. We find, however, that even in the ultraviolet limit it does not differ greatly from the known asymptotic freedom behavior of the propagator. It may, therefore, be a reasonable approximation over the whole range. 相似文献
95.
P. A. Lane C. R. Whitehouse T. Martin M. Houlton G. M. Williams A. G. Cullis S. S. Gill J. R. Dawsey G. Ball B. T. Hughes M. A. Crouch M. B. Allenson 《Journal of Crystal Growth》1992,120(1-4):245-251
This paper describes the first reported use of diethylaluminium hydride-trimethylamine adduct (DEAlH-NMe3) for the growth of GaAs/GaAlAs power heterojunction bipolar transistors (HBTs) by chemical beam epitaxy (CBE). This precursor possesses a significantly higher vapour pressure than the more conventionally used triethylaluminium (TEA), and leads to much less stringent requirements for bubbler and gas-line heating, and also much-improved GaAs/GaAlAs heterojunction definition when no carrier gas is employed. The use of all-gaseous n- and p-type dopants offers significant technological advantages in CBE, and the current paper also provides the first report of the use of hydrogen sulphide for n-type doping of CBE-grown GaAlAs HBT emitter regions. In conclusion, DC and RF data obtained from the heterojunction bipolar transistors fabricated to date are described. A DC gain of 40 has already been measured and encouraging early data obtained from RF-probed devices are also presented. 相似文献
96.
Joseph A. Ball 《Integral Equations and Operator Theory》1996,25(4):377-405
We show how the commutant lifting theorem for nest algebras due to Paulsen and Power can be used to give a unified framework for the treatment of a variety of interpolation problems for nest algebras which have been considered recently in the literature. Applications include the treatment of robust control for time-varying systems.Partially supported by NSF grant DMS-9500912 相似文献
97.
The ultimate goal of our campaign is to generalize a substantial collection of results in classical complex variables to highly nonlinear situations. In [BH1] and subsequent works (c. f. [BGR],[H]) it was shown how an extension of the classical Beurling-Lax-Halmos theorem to Hilbert spasces with a signed bilinear form (indefinite metric) could be regarded as the key to many theorems in complex analysis. Thus our approach to the nonlinear case is to first extend our indefinite metric Beurling-Lax-Halmos theory to nonlinear situations that is the subject of this article.Supported in part by the Air Force Office of Scientific Research, the National Science Foundation and the Office of Naval Research. 相似文献
98.
99.
100.
Matthew C. Ball David S. Brown Alan G. Massey Denys A. Wickens 《Journal of organometallic chemistry》1981,206(3):265-277
Perfluorotribenzo[b,e,h][1,4,7]trimercuronin forms adducts of 1 : 1, 1 : 2 and 1 : 3 stoicheiometry with a variety of polar organic molecules. The structure of the 1 : 1 adduct with 4-phenylpyridine was solved by X-ray methods to an R factor of 7.4% for 3528 observed reflections. 相似文献