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81.
We prove that the space of real analytic functions ${\cal A}(\Omega)$ on an
arbitrary open set $\Omega \subseteq \mathbb{R}^d$ has a
Fréchet infinite dimensional quotient space with a continuous norm.
Received: 4 February 2002 相似文献
82.
R. Vogt 《Acta Physica Hungarica A》2003,18(1):11-20
We describe updated calculations of $Q\bar Q$ production in pp and π - p interactions. We compare these results to total cross section data and discuss how the baseline cross sections extrapolate to heavy ion collider energies. We touch upon the differences between leading and next-to-leading order heavy quark production. Finally, we discuss the implications of our calculations for quarkonium production. Our discussion here focuses on bottom quarks. 相似文献
83.
M. Diehl P. Kroll C. Vogt 《The European Physical Journal C - Particles and Fields》2003,26(4):567-577
We study the handbag contribution to two-photon annihilation into baryon-antibaryon pairs at large energy and momentum transfer.
We derive factorization of the process amplitude into a hard subprocess and form factors describing the soft transition, assuming that the process is dominated by configurations where the (anti)quark approximately carries the full
momentum of the (anti)baryon. The form factors represent moments of time-like generalized parton distributions, so-called
distribution amplitudes. A characteristic feature of the handbag mechanism is the absence of isospin-two components in the
final state, which in combination with flavor symmetry provides relations among the form factors for the members of the lowest-lying
baryon octet. Assuming dominance of the handbag contribution, we can describe current experimental data with form factors
of plausible size, and predict the cross sections of presently unmeasured channels.
Received: 3 July 2002 / Revised version: 7 October 2002 / Published online: 20 November 2002
RID="a"
ID="a" e-mail: mdiehl@physik.rwth-aachen.de
RID="b"
ID="b" e-mail: kroll@physik.uni-wuppertal.de
RID="c"
ID="c" e-mail: cvogt@nordita.dk 相似文献
84.
Fischer S Bitter M Caraccia M Dülk M Gamper E Vogt W Gini E Melchior H Hunziker W 《Optics letters》2001,26(9):626-628
An all-optical sampler consisting of a polarization-independent monolithic Mach-Zehnder interferometer with integrated semiconductor optical amplifiers and a temporal resolution of 1 ps is presented. As an example, a simple 320-Gbit/s pattern has been successfully sampled, demonstrating the functionality of this scheme for high-bit-rate waveform characterizations in light-wave systems. 相似文献
85.
The dynamics of kink motion via atom removal/deposition as a fundamental step in dissolution/crystallization of solids have become directly accessible by a novel scanning tunneling microscopy technique. Results obtained for the electrochemical dissolution of Cu(100) in HCl solution show pronounced local dissolution/redeposition fluctuations at the individual kinks even at the onset of Cu dissolution with average kink propagation and reaction rates in the range 10(3) and 10(5) atoms s(-1), respectively. These experiments allow one to directly measure the central kinetic properties of this electrochemical reaction. 相似文献
86.
Vogt FG Mattingly SM Gibson JM Mueller KT 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2000,147(1):26-35
A background-filtered version of the rotational-echo double resonance (REDOR) experiment is demonstrated. The experiment combines a traditional REDOR pulse sequence with a double-cross-polarization (DCP) sequence to select only those signals coming from spin pairs of interest. The relatively inefficient DCP sequence, which transfers polarization from (1)H to (15)N and subsequently to (13)C, is improved by the use of adiabatic passages through the (-1) sideband of the Hartmann-Hahn matching condition. The result is an efficient 2D-REDOR pulse sequence that does not require a reference experiment for removal of background signals. The data produced by the experiment are ideally suited to analysis by newly developed dipolar transform methods, such as the REDOR transform. The relevant features of the experiment are demonstrated on simple labeled amino acids. Relative efficiencies of several other potential filtering methods are also compared. Copyright 2000 Academic Press. 相似文献
87.
We report combinatorial molecular beam epitaxy synthesis and properties of a ternary epitaxial film of Co and Mn co-doped Ge grown on Ge (0 0 1) substrate. Structural effects were examined in situ by reflection high-energy electron diffraction and ex situ by microbeam X-ray diffraction techniques, and magnetic properties were probed by using magnetooptic Kerr effect. Ternary epitaxial phase diagrams have been studied for total doping concentrations up to 30 at.%, where regions of coherent epitaxy and rough disordered growth and those of near room temperature ferromagnetic ordering have been identified. 相似文献
88.
Wolfgang Scherer Prof. Dr. Christoph Hauf Dipl.‐Phys. Manuel Presnitz Dipl.‐Phys. Ernst‐Wilhelm Scheidt Dr. Georg Eickerling Dr. Volker Eyert Dr. Rolf‐Dieter Hoffmann Dr. Ute C. Rodewald Dipl.‐Ing. Adrienne Hammerschmidt Dr. Christian Vogt Dr. Rainer Pöttgen Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(9):1578-1582
89.
For quality tests of ceramic Bi-Pb-Sr-Ca-Cu-O superconductor materials (precursors and final products) accurate stoichiometric determinations of the metallic major components are necessary. Three methods were developed during the last decade in our group. Their properties and the results obtained are compared. The first classical analytical procedure requires to much manpower. The second combined chemical-spectrometric procedure is a routine method today, but also unsuitable for rapid tests. A new fully spectrometric procedure was recently developed using a simultaneously working Echelle spectrometer with CID detector, autosampler and a special self-made data evaluation software. The basis of this method are multi-line measurements of each analyte element, a new method of spectral line selection for main component precision determinations, multi-component calibrations, and frequent external standardizations. For this method the sum of the confidence intervals of all element determinations was less than 1%, and no systematic error was detected. 相似文献
90.