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991.
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P. Merz R. Grieser G. Huber S. Karpuk V. Sebastian P. Seelig M. Grieser R. Grimm I. Lauer V. Luger D. Schwalm A. Dax T. Engel M. Gerlach T. Kühl H. Winter 《Hyperfine Interactions》1998,115(1-4):53-56
A preparation scheme for a 7Li+ ion beam in a storage ring is presented which provides ions in the metastable triplet states
with well controlled longitudinal phase space properties. For both state selective preparation and beam cooling, laser- and
electron-cooler forces are applied. The spatial- and momentum distributions of the ions are directly detected by a time resolved
measurement of the fluorescence light. At low beam intensities, the remaining heating rate of such a beam is completely determined
by residual gas scattering.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
995.
996.
Walter O. Rom Frederick W. Winter 《The Journal of the Operational Research Society》1981,32(3):223-232
A method of scheduling new product evaluation steps is proposed. The method presented offers promise in reducing the costs of this evaluation. The value of each evaluation is based on Bayesian methods. 相似文献
997.
998.
P.H. Heckmann E. Träbert H. Winter F. Hannebauer H.H. Bukow H.v. Buttlar 《Physics letters. A》1976,57(2):126-128
Radiative lifetimes of oxygen ions accelerated to 15 MeV and excited by a thin carbon foil have been measured using a grazing-incidence spectrometer. Where theoretical values are available, the measured lifetimes agree well with theory. 相似文献
999.
H. De Kerret E. Nagy R.S. Orr M. Regler W. Schmidt-Parzefall K. Winter A. Brandt H. Dibon G. Flügge F. Niebergall P.E. Schumacher K.R. Schubert J.J. Aubert C. Broll G. Coignet J. Favier L. Massonnet M. Vivargent G. Neuhofer 《Physics letters. [Part B]》1977,69(3):372-376
We report on a study of the charge-exchange reaction pp → nΔ++(1232) at the CERN intersecting storage rings (ISR) in the energy range √s = 23 to 53 GeV. From our analysis of the energy dependence of the total cross-section, of the differential cross-section dσ/dt and of the decay angular distributions we find evidence that pion exchange is dominant up to √s = 23 GeV and that (?+A2) exchange dominates the reaction for √s ? 30 GeV, as described by simple Regge-pole models. 相似文献
1000.
M. Jonker F. Udo J. V. Allaby U. Amaldi G. Barbiellini A. Capone W. Flegel M. Metcalf J. Meyer F. L. Navarria J. Panman A. M. Wetherell K. Winter F. W. Büsser H. Daumann P. D. Gall E. Metz F. Niebergall K. H. Ranitzsch P. Stähelin E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli B. Borgia C. Bosio F. Ferroni E. Longo P. Monacelli F. de Notaristefani P. Pistilli C. Santoni V. Valente 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):211-217
The question whether scalar-type interactions contribute to weak interactions at large momentum transfer has been investigated by a measurement of the longitudinal polarization of positive muons produced in charged-current interactions of high-energy antineutrinos with iron. At an average momentum transfer <Q 2>=4 GeV2 the muon spin is found to be oriented forward with respect to the muon momentum vector, with an average polarization of 1.10±0.24, consistent with positive helicity. A limit on scalar contributions of σs, p/σtot <7% at the 95% confidence level can be deduced. A search for violation of time reversal invariance which could manifest itself by a polarization component perpendicular to the muon production plane gave a limit of σtv/σtot <16% (95% c.l.). It is concluded that the weak leptonic charged current retains its dominant vector and axial vector structure at large momentum transfers. 相似文献