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Different interpretations of narrow structures at $W\sim 1.68$ and $W\sim 1.72$ GeV observed in several reactions are discussed. It is questionable whether interference phenomena could explain the whole complex of experimental findings. More probable hypotheses would be the existence of one or two narrow resonances $N(1685)$ and $N(1726)$ and/or the sub-threshold virtual $K\Sigma$ and $\omega p$ production (cusps)., Comment: Published version

This article deals with the problem of choosing of most effective development of Russian small and medium-sized businesses by transition from the strategy of concentration to the strategy of diversification. The author considers the questions of diversification feasibility, its benefits, criteria for selecting of a path of diversification, classification of diversification strategies.

We report on a measurement ofthe neutron detection efficiency in NaI crystals in the Crystal Ball (CB)

We report on an investigation of the ({pi}{sup -}, {pi}{sup 0}{pi}{sup 0}) reaction by means of the {pi}{sup 0}{pi}{sup 0} invariant mass distributions from {pi}{sup -} interactions on H, D, C, Al, and Cu targets at {rho}{sub {pi}{sup -}} = 0.408 GeV/c. The sharp, strong peak in the {pi}{sup +}{pi}{sup -} invariant mass near 2m{sub {pi}} reported by the CHAOS Collaboration is not seen in our {pi}{sup 0}{pi}{sup 0} data. However, we do observe a change in the shape of the {pi}{sup 0}{pi}{sup 0} invariant mass spectrum for the different targets, indicating that the {pi}{sup 0}{pi}{sup 0} interaction diminishes in the nuclear medium as represented by nuclei D, C, Al, and Cu, compared to hydrogen.

An algorithm is developed and tested for assessing the types and concentrations of sea ice on the basis of data obtained from two‐band active and passive microwave sensors, using a priori values of the scattering parameters and natural emission of basic types of ice for the corresponding characteristics of the observation system—frequency, polarization, and observation angle—and a linear mixture model for the measured radiobrightness temperature and specific effective scattering area. The results of satellite monitoring with a side‐looking radar with a real SLR aperture and an RM‐08 microwave radiometer, of the region of the Barents‐Kara‐Laptev seas and the adjacent Arctic Ocean, were used in organizing a satellite database for the period October 1995–March 1996, in compiling digital mosaic charts of the ice cover, and in making a comparative analysis with the corresponding charts prepared by the U.S. Navy and National Oceanic and Atmospheric Administration.

Measured values of the differential cross sections for pion-nucleon charge exchange, π-p→π0n, are presented for π- momenta of 103, 112, 120, 130, 139, 152, and 178 MeV/c. Complete angular distributions were obtained by using the Crystal Ball detector at the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Statistical uncertainties of the differential cross sections vary from 3 to 6% in the backward angle region and from 6 to about 20% in the forward region with the exception of the two most forward angles. The systematic uncertainties are estimated to be about 3% for all momenta.

The differential cross section for {eta} production in reaction {pi}{sup -}p{yields}{eta}n has been measured over the full angular range at seven incident {pi}{sup -} beam momenta from threshold to p{sub {pi}}{sub {sup -}}=747 MeV/c using the Crystal Ball multiphoton spectrometer. The angular distributions are S wave dominated. At 10 MeV/c above threshold, a small D-wave contribution appears that interferes with the main S wave. The total {eta} production cross section {sigma}{sup tot} is obtained by integration of d{sigma}/d{omega}. Starting at threshold, {sigma}{sup tot} rises rapidly, as expected for S-wave-dominated production. The features of the {pi}{sup -}p{yields}{eta}n cross section are strikingly similar to those of the SU(3) flavor-related process K{sup -}p{yields}{eta}{lambda}. Comparison of the {pi}{sup -}p{yields}{eta}n reaction is made with {eta} photoproduction.

The study of the light baryon resonances, in particu-lar the determination of their electromagnetic couplings,is undergoing a resurgence driven by a stream of new,high-precision data emanating from experimental pro-grams at modern photon facilities. The main propertiesof the ∆(1232) resonance, the mass, pole value, masssplittings, width, and branching ratio for different decay

Reaction K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{sigma}{sup 0} was measured with the Crystal Ball multiphoton spectrometer at eight K{sup -} momenta from 514 to 750 MeV/c. Dynamics and the energy dependence of the reaction are shown by Dalitz plots, invariant mass spectra, production angular distributions, and total cross sections. The dipion invariant-mass spectra for K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{sigma}{sup 0} show an enhancement in the low mass region; the opposite is the case for the K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{lambda} and {pi}{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}n reactions. There is no direct evidence for a f{sub 0}(600)-meson contribution to {pi}{sup 0}{pi}{sup 0} production. Everywhere {sigma}{sub t}(K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{sigma}{sup 0})<

Data are presented for the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}n$ in the range from threshold to ${p}_{{\ensuremath{\pi}}^{\ensuremath{-}}}=750\text{ }\text{ }\mathrm{M}\mathrm{e}\mathrm{V}/c$. The systematics of the data and multipole analyses are examined for sensitivity to a ${f}_{0}(600)$ (``$\ensuremath{\sigma}$'') meson. A one-pion-exchange mechanism is found to be very weak, or absent. The reaction appears to become dominated by sequential ${\ensuremath{\pi}}^{0}$ decays through the $\ensuremath{\Delta}(1232)$ resonance as the beam momentum increases, along with substantial interference effects from several competing mechanisms.

Data are presented for the reaction pi(-)p--pi(0)pi(0)n in the range from threshold to p(pi(-))=750 MeV/c. The systematics of the data and multipole analyses are examined for sensitivity to a f(0)(600) ("sigma") meson. A one-pion-exchange mechanism is found to be very weak, or absent. The reaction appears to become dominated by sequential pi(0) decays through the Delta(1232) resonance as the beam momentum increases, along with substantial interference effects from several competing mechanisms.

This study addresses the influence of synthetic aperture radar (SAR) data-focusing parameters on the efficiency of tundra habitat classification. IBM PC/AT-compatible software was developed for synthesizing images from the raw SAR data and the complex SAR images, The focusing algorithm, based on matched filtering allows to control spatial resolution by means of multi-look technique and provides a set of window functions (Rectangle, Hamming, Kaiser-Bessel and etc.) for flexible adjustment of the synthesized gain pattern. The set of ALMAZ and ERS-1 SAR images was generated from a single satellite overpass for a 21 km/sup 2/ study site (flat, wet tundra) at Prudhoe Bay, Alaska. Special spectral classification method was applied to each image and the results were compared with a ground-truth map. The images were classified to best approximate two ground classification schemes: "C" (based on vegetation) and "D" (based on surface form). Results indicated that the number of processing "looks" had a greater influence than windowing function with respect to overall classification agreement with ground classes when texture was not taken into account. Four-look processing was superior to one-look processing for discriminating general landcover types. The choice of windowing function appeared to have greater importance in the detection of specific ground features. The results of classification suggest that an optimal combination of SAR data-focusing parameters may exist-for every ground-derived classification scheme.

Recently the Crystal Ball Collaboration measured precise new data for the near-threshold reaction K(-)p-->etaLambda, which is dominated by formation of the Lambda(1670)1 / 2(-). In this Letter, we present results of a unitary, multichannel analysis that incorporates the new Crystal Ball data. For our preferred fit, we obtain mass M = 1673+/-2 MeV, width Gamma = 23+/-6 MeV, and elasticity x = 0.37+/-0.07. This elasticity is significantly larger than previously recognized. Resonance parameters of our preferred fit are in striking agreement with the quark-model predictions of Koniuk and Isgur.

We have determined the quadratic slope parameter $\ensuremath{\alpha}$ for $\ensuremath{\eta}\ensuremath{\rightarrow}3{\ensuremath{\pi}}^{0}$ to be $\ensuremath{\alpha}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.031(4)$ from a $99%$ pure sample of ${10}^{6}\ensuremath{\eta}\ensuremath{\rightarrow}3{\ensuremath{\pi}}^{0}$ decays produced in the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}n\ensuremath{\eta}$ close to the $\ensuremath{\eta}$ threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations.

We present measurements of the differential and total cross sections and the {Lambda} polarization for the reaction K{sup -}p{yields}{eta}{Lambda} from threshold to p{sub K}-=770 MeV/c, with much better precision than previous measurements. Our cross-section data show a remarkable similarity to the SU(3) flavor-related {pi}{sup -}p{yields}{eta}n cross-section results. The reaction K{sup -}p{yields}{eta}{Lambda} at threshold is dominated by formation of the intermediate {Lambda}(1670)1/2- state.

We have determined the quadratic slope parameter alpha for eta--3pi(0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta--3pi(0) decays produced in the reaction pi(-)p--n(eta) close to the eta threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations.

We report on an investigation of the (pi(-),pi(0)pi(0)) reaction by means of measurements of the pi(0)pi(0) invariant mass distributions from pi(-) interactions on H, D, C, Al, and Cu targets at p(pi(-)) = 0.408 GeV/c. The sharp, strong peak in the pi(+)pi(-) invariant mass near 2m(pi) reported by the CHAOS Collaboration is not seen in our pi(0)pi(0) data. However, we do observe a change in the shape of the pi(0)pi(0) invariant mass spectrum for the different targets, indicating that the pi(0)pi(0) interaction diminishes in the nuclear medium as represented by nuclei D, C, Al, and Cu, compared to hydrogen.