Canonical structure of the CP sigma model in 1 + 2 dimensions

The CP^N model with a θ-term in 1 + 2 dimensions is quantized canonically. By employing a suitable parametrization we demonstrate that solitons carry θ-dependent fractional spins.     

A perturbative QCD estimate of the η1-Mass

Using perturbative QCD expansions for the two-point correlation function of the U_A(1) current in a properly constructed dispersion sum rule, and using a previously obtained estimate for the strange quark mass, we obtain a realistic upper bound on the η₁-mass.     

The quantization of the Gürsey model

The Gürsey model, a conformally invariant pure spinor model in four dimensions, is quantized to result in an asymptotically free theory.     

Investigation of cw injection laser with external dispersive cavity

Tunable single-frequency lasing with output power up to 9 mW was achieved in an injection laser with an external dispersive cavity. The bistable lasing mode was investigated theoretically and experimentally. It is shown that its presence is due to the laser-diode active-region optical nonlinearity. Investigation of equal-frequency fluctuation spectra of the output power has shown that only modes with differing transverse structures can be excited simultaneously. Suppression of weak modes by the field of a strong mode was observed. This increases the stability of the single-frequency lasing as the laser output power is increased.Translated from Trudy Ordena Lenina Fizicheskogo Instituta im. P. N. Lebedeva, Vol. 141, pp. 62–88, 1983.     

Polarized target asymmetry in π° photoproduction between 0.4 and 1.0 GeV around 100°

The polarized target asymmetry in the reaction γp→π°p has been measured at c.m. angles around 100° for photon energies between 0.4 and 1.0 GeV by detecting both the recoil proton and the π°. The result is compared with recent analyses.     

Rapid photoresponses in the retina and their relevance to vision research

Abstract— An intense short flash stimulus gives rise to transient electrical responses of about a millisecond duration from vertebrate and some invertebrate retinas. Some aspects of these rapid retinal responses are reviewed. It is concluded that they probably represent electrical expressions of photochemical events or events closely associated with photochemistry of visual pigment, that they do not represent the excitation of the photoreceptors per se, and that still unidentified, silent processes intervene between them and the excitation of the photo-receptor. The fact that photochemical events produce movements of charges, which result in these responses, is of interest in itself. Moreover, these responses present us with a relatively simple and effective technique for probing the role of visual pigment in visual excitation in the intact retina.     

Superfield formulation of the simplest three-dimensional gauge theories and conformal supergravities

Tashkent State University. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 77, No. 1, pp. 97–106, October, 1988.     

Minor and Trace Sterols in Marine Invertebrates. XII. Occurrence of 24 (R + S)-isopropenylcholesterol, 24 (R + S)-methylcholesta-5, 25-dien-3β-ol,and 24 (R + S)-methylcholesta-7, 25-dien-3β-ol in the caribbean sponge,Verongia cauliformis

In addition to the two new sterols verongulasterol 11 and 25-dehydroaplysterol 13 of Verongia cauliformis³), which were reported earlier [2] [3], the minor and trace sterols of this sponge include five new sterols listed in the title (with the exception of the known 24 S-methyl-cholesta-5, 25-dien-3β-ol (codisterol, 1b ). The isolation of the 24(R)-epimer of codisterol is of interest, as this compound is a possibly biosynthetic precursor for aplysterol 12 , 25-dehydroaplysterol 13 , and verongulasterol 11 (all 24R) which occur in the same sponge [2]. A partial synthesis from fucosterol ( 4 ) of 24 (R + S)-isopropenylcholesterol ( 9 ), and of 24-isopropylcholesterol ( 10 ) is described.     

Axial anomaly and chiral symmetry breaking in Schwinger model: A canonical approach

We use a recently introduced canonical surface formalism, to study the problem of chiral symmetry breaking in the Schwinger model. We perfect the parallel between QCD₄ and QED₂ in this respect.