Ground state of the 4α + Λ nucleus within the 4α+Λ cluster model

The s-wave bound state of the 4α+Λ system is investigated. The relevant solution to the Schrödinger equation is expanded in the basis formed by the eigenfunctions of Hamiltonian for the 4α subsystem. Differential equations for Yakubovsky components are employed to calculate basis functions. Phenomenological potentials for αα and αΛ interactions are used. In the 4α system, additional three-particle potentials for the interaction between α clusters are introduced in such a way as to reproduce the experimental data on the binding energies, the root-mean-square radii, and the charge form factors for the ¹²C and the ¹⁶O nucleus. The binding energy, the root-mean-square radius, and the hyperon distribution in the ground state of the _Λ ¹⁷ O nucleus are calculated. The results of the calculations are in good agreement with those obtained on the basis of the ¹⁶O+Λ two-particle model with the phenomenological Woods-Saxon potential.     

Calculation of the binding energy and of the parameters of low-energy scattering in the Λnp system

The cluster-reduction method is used to solve the differential Faddeev equations for S=1/2, T=0 and S=3/2, T=0 spin-isospin states of the Λnp system in the s-wave approximation. The NN interaction is simulated on the basis of the MT I–III potential model, and the ΛN potential is set to V _ΛN =V _NN /2. This simple option makes it possible to reproduce faithfully the binding energy of the hypertriton _Λ ³ H. The doublet and quadruplet Λd scattering lengths and the low-energy phase shifts are calculated. It is shown that the effective-range approximation is applicable to the cases of doublet and quadruplet scattering.     

Structure of the Products of Stimulated Carbonization of Aromatic Hydrocarbons

This paper deals with X-ray photoelectron and electron microscopy studies of the structure of carbon–metal-containing micro- and nanotubulenes. Ab initio quantum-chemical calculations were performed to analyze the possibility and mechanism of tubulene formation.     

Surface Polaritons in GaAs/CdTe/PbTe Multilayer Structures

JETP Letters - Infrared spectra of reflection and attenuated total reflection of PbTe thin films deposited by molecular beam epitaxy on a GaAs/CdTe substrate have been measured. The high-frequency...     

Operating energy-measurement standard for 10.6-μm pulsed laser emission

Problems of instrumentation for the measurement of C0₂-1aser pulses at 10.6 vm and of development of a working standard and high-accuracy test equipment are considered.Translated from Voprosy Metrologicheskogo Obsepecheniya Izmereniya Parametrov Tekhnologicheskikh Lazerov, pp. 69–79, 1984.     

Cumulative interaction in the deflection cavities of a high-powermagnicon amplifier

A major factor limiting the output power of a high-power magnicon is RF breakdown in its penultimate cavity. Utilization of the principal of angle summing allows us to achieve cumulative interaction between a beam and RF fields of the magnicon deflection system, and thus to decrease the maximum electric field in the penultimate cavity. In this paper, the problems of implementing a cumulative interaction in a magnicon deflecting system are discussed. A deflecting system with coupled cavities working according to the principal of angle summing, which has been tested with success experimentally, has a limitation caused by instabilities that can limit pulse duration at a power level higher than a few tens of milliwatts. The method described employs a set of uncoupled penultimate cavities to obtain cumulative interaction at high power without sacrifice of pulsewidth     

Implicit functions determined by equations with unbounded operators and the solvability of operator equations

For implicit functions determined by the equation T_x+F(λ,x)=0, where T is an unbounded operator, existence and differentiability conditions are established. As an application, the solvability conditions for equations of the form Tx+f(x)=0 are derived. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 248, 1998, pp. 216–224. Translated by L. Yu. Kolotilina.     

Reactions of 2-alkylsulfanyl- and 2-alkoxy-4-hydroxy-6<Emphasis Type="Italic">H</Emphasis>-1,3-oxazin-6-ones with O-nucleophiles

Reactions of 2-alkylsulfanyl- and 2-alkoxy-4-hydroxy-6H-1,3-oxazin-6-ones with oxygen-centered nucleophiles were studied. 2-Alkoxy-4-hydroxy-6H-1,3-oxazin-6-ones reacted with water and alcohols to give the corresponding alkyl 3-amino-3-oxopropanoates as a result of opening of the oxazine ring at the C⁶-O bond, whereas their 2-alkylsulfanyl analogs turned out to be stable toward O-nucleophiles. The different reactivities of the title compounds were interpreted in terms of quantum-chemical calculations of their electronic structure.     

Reactions of 4-Hydroxy-2H-pyran-2-ones with Some N-Nucleophiles

Russian Journal of General Chemistry -