61 research outputs found
ERRATUM TO: Power corrections to parton sum rules for deep inelastic scattering from polarized targets
We clarify conflicting results in the literature on coefficient functions in
front of higher twist operators contributing to the parton sum rules for deep
inelastic scattering from polarized targets. The necessary corrections do not
affect our calculations of matrix elements, published in
Phys.Lett.B242(1990)245, but change final estimates of the
contributions to Bjorken and Ellis--Jaffe sum rules.Comment: 2 pages, MPI-Ph/93-0
Muon capture by 3He nuclei followed by proton and deuteron production
The paper describes an experiment aimed at studying muon capture by
nuclei in pure and mixtures at various densities. Energy distributions of
protons and deuterons produced via and are measured for the
energy intervals MeV and MeV, respectively. Muon capture
rates, and are obtained using two different analysis methods. The
least--squares methods gives , . The Bayes theorem
gives ,
. The experimental
differential capture rates, and , are compared with theoretical
calculations performed using the plane--wave impulse approximation (PWIA) with
the realistic NN interaction Bonn B potential. Extrapolation to the full energy
range yields total proton and deuteron capture rates in good agreement with
former results.Comment: 17 pages, 13 figures, accepted for publication in PR
Noncommutativity and Tachyon Condensation
We study the fuzzy or noncommutative Dp-branes in terms of infinitely many
unstable D0-branes, from which we can construct any Dp-branes. We show that the
tachyon condensation of the unstable D0-branes induces the noncommutativity. In
the infinite tachyon condensation limit, most of the unstable D0-branes
disappear and remaining D0-branes are actually the BPS D0-branes with the
correct noncommutative coordinates. For the fuzzy S^2 case, we explicitly show
only the D0-branes corresponding to the lowest Landau level survive in the
limit. We also show that a boundary state for a Dp-brane satisfying the
Dirichlet boundary condition on a curved submanifold embedded in the flat space
is not localized on the submanifold. This implies that the Dp-brane on it is
ambiguous at the string scale and solves the problem for a spherical D2-brane
with a unit flux on the world volume which should be equivalent to one
D0-brane. We also discuss the diffeomorphism in the D0-brane picture.Comment: 30 pages, references added, minor corrections and clarifications,
version to appear in JHE
Study of doubly strange systems using stored antiprotons
Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the P‾ANDA experiment at FAIR. For the first time, high resolution γ-spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ−-atoms will be feasible and even the production of Ω−-atoms will be within reach. The latter might open the door to the |S|=3 world in strangeness nuclear physics, by the study of the hadronic Ω−-nucleus interaction. For the first time it will be possible to study the behavior of Ξ‾+ in nuclear systems under well controlled conditions
Method of synthesis of measurings signals for control of the technical state of standards of armament at integral limitation
Запропонована методика синтезу оптимального вимірювального сигналу для контролю технічного стану зразка озброєння при інтегральному обмежені. Наведений приклад застосування розробленої методики для розрахунку параметрів оптимального вимірювального сигналу при контролі характеристик зразка. Визначена форма оптимального вимірювального сигналу в залежності від параметрів контрольованого зразка озброєння та умов проведення контролю.Предложена методика синтеза оптимального измерительного сигнала для контроля технического состояния образца вооружения при интегральном ограничении. Приведен пример применения разработанной методики для расчета параметров оптимального измерительного сигнала при контроле характеристик образца вооружения. Определена форма оптимального измерительного сигнала в зависимости от параметров контролируемого образца вооружения и условий проведения контроля.The method of synthesis of optimum measuring signal is offered for control of the technical state of standard of armament at integral limitation. The example of application of the developed method is resulted for the calculation of parameters of optimum measuring signal at control of descriptions of standard of armament. The form of optimum measuring signal is certain depending on the parameters of the controlled standard of armament and terms of the use of control
Polycondensation of carboxyclic acid difluorides with diamines in homogeneous aqueous and organic media
Use of malonic acid to prevent the osteoresorptive effect of dark stress in broiler chicks
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