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41.
C. Herberg M. Ostrick H.G. Andresen J.R.M. Annand K. Aulenbacher J. Becker P. Drescher D. Eyl A. Frey P. Grabmayr S.J. Hall P. Hartmann T. Hehl W. Heil J. Hoffmann D. Ireland J.D. Kellie F. Klein K. Livingston Ch. Nachtigall A. Natter E.W. Otten R.O. Owens E. Reichert D. Rohe H. Schmieden R. Sprengard M. Steigerwald K.-H. Steffens Th. Walcher R. Watson 《The European Physical Journal A - Hadrons and Nuclei》1999,5(2):131-135
The electric form factor of the neutron G
E,n has been determined at the Mainz Microtron MAMI at the low momentum transfer Q
2= 0.15 (GeV/c)2 in a measurement of the recoil polarisation ratio P
x/Pz in the quasifree reaction D(e,e′n)p. At this Q
2 the influence of the nuclear binding is strong. A purely kinematical model is used to get some insight into the effect of
the initial Fermi momentum distribution of the neutron. The influence of the final state interaction is determined quantitatively
by a model of Arenh?vel et al.. After the corresponding corrections a value of G
E,n(0.15 (GeV/c)2) = 0.0481±0.0065stat±0.0053syst is obtained.
Received: 12 April 1999 相似文献
42.
C. Brahm Gertrud Andresen H. Thomas H. Michaelis Th. Sabalitschka M. W. Zahner F. Mach und P. Lederle 《Fresenius' Journal of Analytical Chemistry》1932,88(7-8):315-317
Ohne Zusammenfassung 相似文献
43.
Harro G. Andresen 《Zeitschrift für Physik A Hadrons and Nuclei》1969,223(1):71-102
The conventional atomic beam preparation technique for hydrogen maser operation consists of a six pole magnetic field focussing in combination with adiabatically changing magnetic fields in the transition region between focusser and maser cavity, which results in a state selected, polarized ensemble of hydrogen atoms. Hydrogen maser operation with state selected, but unpolarized atoms has the advantage to reduce considerably the sensitivity of hydrogen maser frequency on coherently excited, low frequency,Δm F =±1 Zeeman transitions. The influence of the magnetic field pattern in the transition region on the energy level population probabilities for the focussed hydrogen beam has been analysed. Atomic beam preparation techniques using non-adiabatically changing magnetic field configurations in the transition region are described. The dependence of hydrogen maser oscillation on the energy level population within the atomic beam is theoretically investigated and the results are used for the analysis of the experimentally achieved atomic beam populations. It has been shown that a pulsed magnetic spin guidance field in the transition region, which switches between adiabatically changing magnetic field configurations and a sudden magnetic field reversal, results in an ensemble of hydrogen atoms with vanishing time averaged polarization, which does not deteriorate the conventionally achieved maser oscillation amplitude. 相似文献
44.
Let λ1 and α1 be respectively the eigenvalue of largest modulus and largest singular value of a linear operator A. Then A is called radial if |λ1| = α1. This paper is concerned with an examination of radial compound matrices. It turns out that the radial property for compound matrices is equivalent to an investigation of the case of equality in the classical inequalities of H. Weyl relating products of eigenvalues and singular values. 相似文献
45.
A. F. Andresen P. Fischer W. Halg E. Stoll E. Baldinger H. Simmen G. Matile 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1964,15(6):655-658
Ohne Zusammenfassung 相似文献
46.
Single atomic collision and thermodynamic equilibrium level populations are compared. The population distributions for relatively cascade free levels with similar lifetimes are shown to be easily described by a Boltzmann relation even if the excitation mechanism is non-thermal. 相似文献
47.
Per Arild Kjølseth Andresen Xiaoli Yang Johan Sjöblom Harald Linga Finn P. Nilsen 《Journal of Dispersion Science and Technology》2013,34(1-2):187-196
The droplet size distribution (DSD) of unstable water/oil dispersions has been studied with a new technique. The technique is based on a fast dilution of the dispersion injected into an analysis vessel where the DSD is analyzed with a video camera and a image analyzing tool. Dispersions generated with no pressure drop in the flow rig were compared to those generated with a pressure drop over a needle valve. The latter dispersion showed a much narrower DSD and a lower average droplet diameter. The results are from preliminary experiments in order to evaluate the method. 相似文献
48.
Birgit Andresen Jan Sandström 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):423-424
Abstract 1,3-oxathianes and 1,3-dithianes, with and without p-bromophenyl group in position 2, have been oxidized to sulphoxides. Both starting materials and oxidation products have been resolved by chromatography, and CD spectra have been recorded. Absolute configuration for the p-bromophenyl compounds have been assigned on the basis of known absolute configurations for analogous 1,3-oxathiolanes. 相似文献
49.
Andresen GB Ashkezari MD Baquero-Ruiz M Bertsche W Bowe PD Butler E Cesar CL Chapman S Charlton M Deller A Eriksson S Fajans J Friesen T Fujiwara MC Gill DR Gutierrez A Hangst JS Hardy WN Hayden ME Humphries AJ Hydomako R Jonsell S Madsen N Menary S Nolan P Olin A Povilus A Pusa P Robicheaux F Sarid E Silveira DM So C Storey JW Thompson RI van der Werf DP Wurtele JS Yamazaki Y;ALPHA Collaboration 《Physical review letters》2011,106(14):145001
Charges in cold, multiple-species, non-neutral plasmas separate radially by mass, forming centrifugally separated states. Here, we report the first detailed measurements of such states in an electron-antiproton plasma, and the first observations of the separation dynamics in any centrifugally separated system. While the observed equilibrium states are expected and in agreement with theory, the equilibration time is approximately constant over a wide range of parameters, a surprising and as yet unexplained result. Electron-antiproton plasmas play a crucial role in antihydrogen trapping experiments. 相似文献
50.
Spectral compression by self-phase modulation of amplitude- and phase-shaped pulses is demonstrated as superior compared to pulses that have only been phase shaped. We synthesize linearly negatively chirped parabolic pulses, which we send through a nonlinear photonic crystal fiber, in which self-phase modulation compresses the spectrum of the pulses to within 20% of the Fourier transform limit. 相似文献