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121.
Representations for inverses of Toeplitz-plus-Hankel matrices and more general Bezoutians involving only discrete Hartley transforms and diagonal matrices are presented. Using these representations a column vector can be multiplied by the inverse of a Toeplitz-plus-Hankel matrix with the help of only 6 Hartley transforms plus O(n) operations. This complexity estimate is significantly better than previous ones. 相似文献
122.
M. Unverzagt P. Aguar-Bartolomé J. Ahrens J. R. M. Annand H. J. Arends R. Beck V. Bekrenev B. Boillat A. Braghieri D. Branford W. J. Briscoe J. W. Brudvik S. Cherepnya R. Codling E. J. Downie L. V. Fil’kov D. I. Glazier R. Gregor E. Heid D. Hornidge O. Jahn V. L. Kashevarov R. Kondratiev M. Korolija M. Kotulla D. Krambrich B. Krusche M. Lang V. Lisin K. Livingston S. Lugert I. J. D. MacGregor D. M. Manley M. Martinez-Fabregate J. C. McGeorge D. Mekterovic V. Metag B. M. K. Nefkens A. Nikolaev R. Novotny R. O. Owens P. Pedroni A. Polonski S. N. Prakhov J. W. Price G. Rosner M. Rost T. Rostomyan S. Schumann D. Sober A. Starostin I. Supek C. M. Tarbert A. Thomas Th. Walcher D. P. Watts F. Zehr 《The European Physical Journal A - Hadrons and Nuclei》2009,39(2):169-177
A precise measurement of the Dalitz plot parameter, $ \alpha$ , for the $ \eta$ → 3 $ \pi^{0}_{}$ decay is presented. The experiment was performed with the Crystal Ball and TAPS large-acceptance photon detectors at the tagged photon beam facility of the MAMI-B electron accelerator in Mainz. High statistics of 1.8 · 106 $ \eta$ → 3 $ \pi^{0}_{}$ events were obtained, giving the result $ \alpha$ = - 0.032±0.002stat±0.002syst . 相似文献
123.
Torsten Henkel Detlef Rost Ian C. Lyon 《Rapid communications in mass spectrometry : RCM》2009,23(21):3355-3360
Time‐of‐flight secondary ion mass spectrometry is a very useful tool for the comprehensive characterization of samples by in situ measurements. A pulsed primary ion beam is used to sputter secondary ions from the surface of a sample and these are then recorded by a time‐of‐flight mass spectrometer. The parallel detection of all elements leads to very efficient sample usage allowing the comprehensive analysis of sub‐micrometre sized samples. An inherent problem is accurate quantification of elemental abundances which mainly stems from the so‐called matrix effect. This effect consists of changes in the sputtering and ionization efficiencies of the secondary neutrals and ions due to different sample compositions, different crystal structure or even different crystallographic orientations. Here we present results obtained using C60 molecules as a new primary ion species for inorganic analyses. The results show an improvement in quantification accuracy of elemental abundances, achieving relative errors as small as the certified uncertainties for the analyzed silicate standards. This improvement is probably due to the different sputter mechanism for C primary ions from that for single atomic primary ions such as Ga+, Cs+ or Ar+. The C cluster breaks up on impact, distributing the energy between its constituent carbon atoms. In this way it excavates nano‐craters, rather than knocking out single atoms or molecules from the surface via a collision cascade, leading to a more reproducible sputter process and much improved quantification. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
124.
Baumberger F Ingle NJ Kikugawa N Hossain MA Meevasana W Perry RS Shen KM Lu DH Damascelli A Rost A Mackenzie AP Hussain Z Shen ZX 《Physical review letters》2006,96(10):107601
High-resolution angular resolved photoemission data reveal well-defined quasiparticle bands of unusually low weight, emerging in line with the metallic phase of Ca(3)Ru(2)O(7) below approximately 30 K . At the bulk structural phase transition temperature of 48 K, we find clear evidence for an electronic instability, gapping large parts of the underlying Fermi surface that appears to be nested. Metallic pockets are found to survive in the small, non-nested sections, constituting a low-temperature Fermi surface with 2 orders of magnitude smaller volume than in all other metallic ruthenates. The Fermi velocities and volumes of these pockets are in agreement with the results of complementary quantum oscillation measurements on the same crystal batches. 相似文献
125.
Hermann Rost 《Probability Theory and Related Fields》1989,83(1-2):1-3
126.
127.
Kotulla M Ahrens J Annand JR Beck R Caselotti G Fog LS Hornidge D Janssen S Krusche B McGeorge JC McGregor IJ Mengel K Messchendorp JG Metag V Novotny R Pfeiffer M Rost M Sack S Sanderson R Schadmand S Watts DP 《Physical review letters》2002,89(27):272001
The reaction gammap-->pi(0)gamma'p has been measured with the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for energies between sqrt[s]=1221-1331 MeV. The cross section's differential in angle and energy have been determined for the photon gamma' in three bins of the excitation energy. This reaction channel provides access to the magnetic dipole moment of the Delta(+)(1232) resonance and, for the first time, a value of mu(Delta(+))=[2.7(+1.0)(-1.3)(stat)+/-1.5(syst)+/-3(theor)]mu(N) has been extracted. 相似文献
128.
Smilauer P Rost M Krug J 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):R6263-R6266
Homoepitaxial growth is unstable towards the formation of pyramidal mounds when interlayer transport is reduced due to activation barriers to hopping at step edges. Simulations of a lattice model and a continuum equation show that a small amount of desorption dramatically speeds up the coarsening of the mound array, leading to coarsening exponents between 1/3 and 1/2. The underlying mechanism is the faster growth of larger mounds due to their lower evaporation rate. 相似文献
129.
130.
Inversion formulas and fast inversion algorithms for matrices the entries of which fulfil a difference equation are established. In that way the Gohberg/Semencul and Gohberg/Krupnik theorems and related results will be generalized. 相似文献