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21.
B. Kotliński D. Androić G. Backenstoss D. Bosnar H. Breuer H. Döbbeling T. Dooling M. Furić P.A.M. Gram N.K. Gregory A. Hoffart C.H.Q. Ingram A. Klein K. Koch J. Köhler M. Kroedel G. Kyle A. Lehmann A.O. Mateos K. Michaelian T. Petković M. Planinić R.P. Redwine D. Rowntree U. Sennhauser N. Šimičević R. Trezeciak H. Ullrich H.J. Weyer M. Wildi K.E. Wilson 《The European Physical Journal A - Hadrons and Nuclei》1998,1(4):435-445
The pion absorption reaction (π+,3
p
) on Ar was studied at pion energies of 70, 118, 162 and 239 MeV, and on N and Xe at 239 MeV. The 3p cross section with a 50 MeV cut on the missing energy is presented. The existence of an initial state interaction (ISI) component
to the reaction was investigated. The portion of the 3p cross section assigned to the ISI process is less than one half and at lower energies significantly so.
Received: 11 December 1997 相似文献
22.
The reactions 17O(d, t) 16O and 17O(d, τ)16N have been investigated at Ed = 52 MeV. Energy spectra of tritons and τ-particles have been measured simultaneously up to excitation energies of 22 MeV in 16O and 10 MeV in 16N, respectively. Spectroscopic factors have been obtained by a DWBA analysis of the measured angular distributions. From the comparison of the t- and τ-spectra analog (T = 1) states in 16O could be identified and the distribution of T = 0 and T = 1 spectroscopic strengths could be deduced. Nearly the total and hole strengths have been found and the particle-hole multiplets could be located both for T = 0 and T = 1. The average residual interactions in both shell-model configurations turned out to be strikingly different. 相似文献
23.
For the displacement boundary value problem in nonlinear elastostatics with zero body force, an integral bound for the strain energy is obtained in terms of theL
2-norms of the given boundary displacements and their tangential derivatives (assumed sufficiently small). The constants involved depend upon the strain energy density function and upon the geometry of the domain. 相似文献
24.
Hans Breuer 《Zeitschrift für Physik A Hadrons and Nuclei》1964,180(2):209-218
The energy spectrum of nearly monoenergetic electrons (energy width about 0.3%) was measured with a spectrometer of high resolution (about 0.1%) before and after passing through aluminum absorbers of thicknesses between 0.08 and 5.4 g/cm2. The experiments were performed with the energy-analysed beam of the Darmstadt linear accelerator; the energy was varied between 20 and 60 MeV. The most probable energy losses agree with the theory ofSternheimer within the error limits (1.5?2%) for thicknesses smaller than 2 g/cm2. The half widths are systematically larger than the values calculated byBlunck andWestphal. 相似文献
25.
26.
Laveissière G Todor L Degrande N Jaminion S Jutier C Di Salvo R Van Hoorebeke L Alexa LC Anderson BD Aniol KA Arundell K Audit G Auerbach L Baker FT Baylac M Berthot J Bertin PY Bertozzi W Bimbot L Boeglin WU Brash EJ Breton V Breuer H Burtin E Calarco JR Cardman LS Cavata C Chang CC Chen JP Chudakov E Cisbani E Dale DS de Jager CW De Leo R Deur A d'Hose N Dodge GE Domingo JJ Elouadrhiri L Epstein MB Ewell LA Finn JM Fissum KG Fonvieille H Fournier G Frois B Frullani S Furget C Gao H Gao J 《Physical review letters》2004,93(12):122001
We report a virtual Compton scattering study of the proton at low c.m. energies. We have determined the structure functions P(LL)-P(TT)/epsilon and P(LT), and the electric and magnetic generalized polarizabilities (GPs) alpha(E)(Q2) and beta(M)(Q2) at momentum transfer Q(2)=0.92 and 1.76 GeV2. The electric GP shows a strong falloff with Q2, and its global behavior does not follow a simple dipole form. The magnetic GP shows a rise and then a falloff; this can be interpreted as the dominance of a long-distance diamagnetic pion cloud at low Q2, compensated at higher Q2 by a paramagnetic contribution from piN intermediate states. 相似文献
27.
Parity-violating electron deuteron scattering and the proton's neutral weak axial vector form factor
Ito TM Averett T Barkhuff D Batigne G Beck DH Beise EJ Blake A Breuer H Carr R Clasie B Covrig S Danagoulian A Dodson G Dow K Dutta D Farkhondeh M Filippone BW Franklin W Furget C Gao H Gao J Gustafsson K Hannelius L Hasty R Hawthorne-Allen AM Herda MC Jones CE King P Korsch W Kowalski S Kox S Kramer K Lee P Liu J Martin JW McKeown RD Mueller B Pitt ML Plaster B Quéméner G Réal JS Ritter J Roche J Savu V Schiavilla R Seely J Spayde D Suleiman R Taylor S Tieulent R Tipton B Tsentalovich E 《Physical review letters》2004,92(10):102003
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions. 相似文献
28.
Industrial methods for the production of optically active intermediates 总被引:15,自引:0,他引:15
Breuer M Ditrich K Habicher T Hauer B Kesseler M Stürmer R Zelinski T 《Angewandte Chemie (International ed. in English)》2004,43(7):788-824
Enantiomerically pure amino acids, amino alcohols, amines, alcohols, and epoxides play an increasingly important role as intermediates in the pharmaceutical industry and agrochemistry, where both a high degree of purity and large quantities of the compounds are required. The chemical industry has primarily relied upon established chemical methods for the synthesis of these intermediates, but is now turning more and more to enzymatic and biotechnological fermentation processes. For the industrial implementation of many transformations alternative methods are available. The advantages of the individual methods will be discussed herein and exemplified by syntheses of relevant compounds. 相似文献
29.
Parity violation in elastic electron-proton scattering and the Proton's strange magnetic form factor
Spayde DT Averett T Barkhuff D Beck DH Beise EJ Benson C Breuer H Carr R Covrig S DelCorso J Dodson G Dow K Eppstein C Farkhondeh M Filippone BW Frazier P Hasty R Ito TM Jones CE Korsch W Kowalski S Lee P Maneva E McCarty K McKeown RD Mikell J 《Physical review letters》2000,84(6):1106-1109
We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A = -4.92+/-0.61+/-0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections. 相似文献
30.
A completely dependent risk process with perturbation and phase-type distributed claim sizes is analyzed. Claim arrivals are modeled by a Markovian arrival process. Using a vector-valued martingale, the Laplace transform of the time to ruin is derived algorithmically. The conditional memoryless property of the phase-type distribution yields the distribution of the deficit at ruin as a corollary. 相似文献