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211.
R. U. Khafizov N. Severijns O. Zimmer H. -F. Wirth D. Rich S. V. Tolokonnikov V. A. Solovei M. R. Kolhidashvili 《JETP Letters》2006,83(1):5-9
The aim of this work is the experimental observation of and research into a rare neutron mode, the radiative beta decay, where
a new particle, the radiative gamma quantum, is formed along with the expected decay products: a beta electron, a recoil proton,
and an antineutrino. The discovery of this rare neutron decay mode was conducted through identification of triple-coincidence
events: simultaneous registration of a beta electron, a proton, and a radiative gamma quantum. The ordinary neutron decay
was registered by double coincidences of a beta electron and a recoil proton. The statistics collected allow one to deduce
the branching ratio (BR) BR = (3.2 ± 1.6) × 10−3 (90% C.L.) in the gamma energy region greater than 35 keV. This value of BR is consistent with standard electroweak theory.
The text was submitted by the authors in English.
An erratum to this article is available at . 相似文献
212.
Yu. V. Vasil’ev R. R. Abzalimov Sh. K. Nasibullaev R. F. Tuktarov F. Hauke U. Reuther A. Hirsch T. Drewello 《Physics of the Solid State》2002,44(3):554-556
The formation and decay of negative molecular ions of azafullerenes and their hydrogenated derivatives are investigated by mass spectrometry. The mechanisms of resonant electron capture and the lifetimes of negative molecular ions with respect to the electron autodetachment in azafullerene molecules are discussed. A comparative analysis of the data obtained for azafullerenes and hydrogenated fullerene derivatives is carried out. 相似文献
213.
F. G. Gerasimato 《Journal of Mathematical Sciences》1991,57(5):3381-3383
We propose a simplified method of determining the integral characteristics of the opening of a parachute which makes it possible to compute the maximal stress on a parachute and the trajectory parameters of the motion of the load in the region of the opening of the parachute, and to determine the size of the portion of the canopy at the time of maximal stress.Translated fromDinamicheskie Sistemy, No. 6, 1987, pp. 38–41. 相似文献
214.
215.
Vijaya Gracias Alan F. Gasiecki Joel D. Moore Irini Akritopoulou-Zanze Stevan W. Djuric 《Tetrahedron letters》2006,47(50):8977-8980
A general method for the preparation of diaza-spirocycles is reported. This method used an olefin metathesis in order to construct the desired spirocyclic framework. Beginning with commercially available protected amino ketones, this strategy ultimately produced pharmacologically relevant diaza-scaffolds in an efficient and high-yielding process. 相似文献
216.
217.
M. F. Gamal' 《Journal of Mathematical Sciences》2006,134(4):2263-2271
We consider a class of C·0-contractions that is a generalization of the class of C·0-contractions with finite defect indices. Some results of Uchigama and Wu for C·0-contractions with finite defect indices are generalized: the lattices of hyperinvariant subspaces of such a contraction T
is isomorphic to that of its Jordan model and is generated by subspaces of the form Ker ϕ(T) and Ran ϕ(T), where ϕ ∈ H∞. The form of the inverse to an isomorphism of the invariant subspace lattices given by an intertwining quasiaffinity is also
studied. Next, for C·0-contractions in question, the characteristic disc related to the lattice of invariant subspaces is computed. Bibliography:
13 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 315, 2004, pp. 48–62. 相似文献
218.
O. Ya. Savchenko 《Optics and Spectroscopy》2006,101(2):179-182
The efficiency with which a magnetic field acts on sublevels of the first and second doublets of a hydrogen-like atom is shown to vary because of relativistic effects by a factor of 1 ? 2γ(l + 1)/(2l + 3) and 1 ? 2γl/(2l ? 1), respectively, where γ is the ratio of the electron binding energy to the rest energy and l is the quantum number of the orbital angular momentum. 相似文献
219.
S. K. Godunov V. T. Zhukov O. B. Feodoritova 《Computational Mathematics and Mathematical Physics》2006,46(6):971-982
An algorithm is constructed for calculating invariant subspaces of symmetric hyperbolic systems arising in electromagnetic, acoustic, and elasticity problems. Discrete approximations are calculated for subspaces that correspond to minimal eigenvalues and smooth eigenfunctions. Difficulties related to the presence of an infinite-dimensional kernel in the differential operator are successfully handled. The efficiency of the algorithm is demonstrated using acoustics equations. 相似文献
220.
Kurenkov V. F. Zaitseva O. A. Kirdyashova G. N. 《Russian Journal of Applied Chemistry》2002,75(4):641-644
The kinetics of radical copolymerization of acrylamide with lithium, sodium, and potassium 2-acrylamido-2-methylpropanesulfonates in concentrated aqueous solutions in the presence of potassium persulfate as initiating agent at pH 9 and 50°C was studied by dilatometry. 相似文献