Deformed Oscillator Algebras and Higher-Spin Gauge Interactions of Matter Fields in 2+1 Dimensions

We formulate a non-linear system of equations which describe higher-spin gauge interactions of massive matter fields in 2+1 dimensional space-time and explain some properties of the deformed oscillator algebra which underlies this formulation. In particular we show that the parameter of mass $M$ of matter fields is related to the deformation parameter in this algebra.Comment: LaTex, 12 pages, no figures; Invited talk at the International Seminar Supersymmetry and Quantum Field Theory dedicated to the memory of Dmitrij V. Volkov; Kharkov, January 1997; to appear in the proceeding

Signal Enhancement in Disperse Solutions for the Analysis of Biomedical Samples by Photothermal Spectroscopy

Photothermal lens spectrometry not only shows high sensitivity of colored heme protein determination, but also provides a change in the sensitivity compared to the theoretical values due to changes in the heat transfer in dispersed media. This can be used for estimating the size of disperse particles exemplified by hemoglobin cyanide, photothermal examination of the state of existence of hemoglobin in highly saline solutions by changes in photothermal properties upon dissociation of hemoglobin tetramers into dimers and monomers. The example of determination of contrast agents (dyes) in blood as the versification of the platform of photoacoustic/photothermal measurement of circulating blood volume is shown

Scalar Mesons in a Chiral Quark Model with Glueball

Ground-state scalar isoscalar mesons and a scalar glueball are described in a U(3)xU(3) chiral quark model of the Nambu--Jona-Lasinio (NJL) type with 't Hooft interaction. The latter interaction produces singlet-octet mixing in the scalar and pseudoscalar sectors. The glueball is introduced into the effective meson Lagrangian as a dilaton on the base of scale invariance. The mixing of the glueball with scalar isoscalar quarkonia and amplitudes of their decays into two pseudoscalar mesons are shown to be proportional to current quark masses, vanishing in the chiral limit. Mass spectra of the scalar mesons and the glueball and their main modes of strong decay are described.Comment: 10 pages, LaTeX text, requires svjour.cls and svepj.cl

Синтез динамических систем, фазовые портреты которых имеют элементарные ячейки данных топологических структур

A method for construction of differential plane dynamical systems which phase portraits have elementary cells with a prescribed topological structure is presented. The solutions of such type inverse problems of differential equations theory may be used to obtain control over dynamical systems behavior.Представлен метод построения дифференциальных динамических систем на плоскости, фазовые портреты которых имеют ячейки с данной топологической структурой разбиения на траектории. Решения такого типа обратных задач теории дифференциальных уравнений могут быть использованы для нахождения управлений поведением динамических систем различной физической природы

Ferromagnetic domain structures and spin configurations measured in doped manganite

We report on measurements of the spin configuration across ferromagnetic domains in La(0.325)Pr(0.3)Ca(0.375)MnO(3) films obtained by means of low-temperature Lorentz electron microscopy with in situ magnetizing capabilities. Due to the particular crystal symmetry of the material, we observe two sets of independent ferromagnetic twin variants, one of which was pinned by crystallographic twinning. The spin orientation and configuration of the domains were measured quantitatively using electron diffraction and electron holography, and verified with structural modeling. The observed deviation of spin orientations from the expected 90 degrees head-to-tail configuration across the domain walls was attributed to the variation in the domains' aspect ratios as a result of the demagnetization field. Our study provides important insight on how the spin configuration coupled with the magnetic structure and the crystal symmetry might affect the magnetoresistivity under an applied magnetic field in a strongly correlated electron system

Application of Photothermal and Photoacoustic Spectroscopy for the Monitoring of Aqueous Dispersions of Carbon Nanomaterials

Photothermal  and  optoacoustic  spectroscopy  in their  state-of-the-art  techniques—multiwavelength, scanning  and  transient—are  used  for  complex investigation  and analysis  (chemical  analysis  and the  estimation  of  physicochemical  properties and size)  of  novel  carbon  materials—fullerenes  and nanodiamonds—and  their aqueous  dispersions  as promising biomedical nanosystems. The estimation of the cluster size and the possibilities to determine subnanogram  amounts  of  both nanodiamonds  and fullerenes  by  these  techniques  are  shown.  The comparison  of fullerene  solutions  in  various solvents,  toluene, N-methylpyrrolydone and  water, is made.  The  advantages  of  the  photothermal  and optoacoustic  techniques  over conventional spectroscopies  and  the  current  limitation  are discussed. The necessity to develop robust  models for  transient  and  imaging  photothermal  techniques is outlined

Virtual Compton Scattering off the Pseudoscalar Meson Octet

We present a calculation of the virtual Compton scattering amplitude for the pseudoscalar meson octet in the framework of chiral perturbation theory at ${\cal O}(p^4)$. We calculate the electromagnetic generalized polarizabilities and compare the results in the real Compton scattering limit to available experimental values. Finally, we give predictions for the differential cross section of electron-meson bremsstrahlung.Comment: 9 pages, Latex, uses cjp3.sty (included), 4 eps figures, to be published in the proceedings of the 13th Indian-Summer School "Understanding the Structure of Hadrons," August 28 - September 1, 2000, Prague, Czech Republi

Topological superfluid 3^3He-B: fermion zero modes on interfaces and in the vortex core

Many quantum condensed matter systems are strongly correlated and strongly interacting fermionic systems, which cannot be treated perturbatively. However, topology allows us to determine generic features of their fermionic spectrum, which are robust to perturbation and interaction. We discuss the nodeless 3D system, such as superfluid $^3$He-B, vacuum of Dirac fermions, and relativistic singlet and triplet supercondutors which may arise in quark matter. The systems, which have nonzero value of topological invariant, have gapless fermions on the boundary and in the core of quantized vortices. We discuss the index theorem which relates fermion zero modes on vortices with the topological invariants in combined momentum and coordinate space.Comment: paper is prepared for Proceedings of the Workshop on Vortices, Superfluid Dynamics, and Quantum Turbulence held on 11-16 April 2010, Lammi, Finlan

Matching Regge Theory to the OPE

The spectra of masses and decay constants for non-strange meson resonances in the energy range 0--2.5 GeV is analyzed. It is known from meson phenomenology that for given quantum numbers these spectra approximately follow linear trajectories with a universal slope. These facts can be understood in terms of an effective string description for QCD. For light meson states the trajectories deviate noticeably from the linear behavior. We investigate the possible corrections to the linear trajectories by matching two-point correlators of quark currents to the Operator Product Expansion (OPE). We find that the allowed modifications to the linear Regge behavior must decrease rapidly with the principal quantum number. After fitting the lightest states in each channel and certain low-energy constants the whole spectrum for meson masses and residues is obtained in a satisfactory agreement with phenomenology. We briefly speculate on possible implications for the QCD effective string.Comment: 24 pages, Latex, significant changes in discussion of fits, more refs adde

Hamiltonian structure and noncommutativity in pp-brane models with exotic supersymmetry

The Hamiltonian of the simplest super $p$-brane model preserving 3/4 of the D=4 N=1 supersymmetry in the centrally extended symplectic superspace is derived and its symmetries are described. The constraints of the model are covariantly separated into the first- and the second-class sets and the Dirac brackets (D.B.) are constructed. We show the D.B. noncommutativity of the super $p$-brane coordinates and find the D.B. realization of the $OSp(1|8)$ superalgebra. Established is the coincidence of the D.B. and Poisson bracket realizations of the $OSp(1|8)$ superalgebra on the constraint surface and the absence there of anomaly terms in the commutation relations for the quantized generators of the superalgebra.Comment: Latex, 27 pages, no figures. Latex packages amsfonts and euscript are use