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We present StarWatch, our application for real-time analysis of radio astronomical data in Virtual Environment. Serving as an interface to radio astronomical databases or being applied to live data from the radio telescopes, the application supports various data filters measuring signal-to-noise ratio (SNR), Doppler's drift, degree of signal localization on celestial sphere and other useful tools for signal extraction and classification. Originally designed for the database of narrow band signals from SETI Institute (setilive.org), the application has been recently extended for the detection of wide band periodic signals, necessary for the search of pulsars. We will also address the detection of week signals possessing arbitrary waveforms and present several data filters suitable for this purpose.

We present a generic approach for focused ultrasonic therapy planning on the basis of numerical simulation, multi-objective optimization, stochastic analysis and visualization in virtual environments. A realistic test case is used to demonstrate the approach. RBF metamodeling of simulation results is performed for continuous representation of two optimization objectives. The non-convex Pareto front of the objectives is determined by means of non-dominated set and local improvement algorithms. Uncertainties of metamodeling are estimated by means of a cross-validation procedure. The 3D visualization in virtual environment framework Avango allows detailed inspection of MRT images, the corresponding material model and spatial distribution of the resulting thermal dose.

Numerical methods for solution of differential equations with deviating arguments describing 1-dimensional ultra-relativistic scattering of 2 identical charged particles in classical electrodynamics with half-retarded/halfadvanced interaction (Wheeler and Feynman, 1949) are developed. A bifurcation of solutions and violation of their reflectional symmetries in the region of velocities v>0.937c are found in numerical analysis.

The tools for visualization of relativistic string dynamics in various topological classes are developed. New theoretical results, obtained with the aid of these tools, are described.

Inclusive production of Δ ++ (1232) with >| t p, Δ ++>| c ) 2 is studied in 32 GeV/ c K + p interactions. A systematic comparison with the reaction K + p→pX for >| t p,p>| c ) 2 is made. The production properties of the Δ ++ (1232), of associated π + , π − and K 0 production and of the recoiling system X 0 are investigated in detail. The polarization of the Δ ++ and the energy dependence of the total K + π − cross sections, determined by a Chew-Low extrapolation, are presented and discussed.

A scintillation-counter hodoscope spectrometer developed at IHEP to detect high-energy photons is described. The detector can simultaneously measure the position (to 2 mm) and energy (5–10%) of several photons. The device is made with 648 scintillation counters, arranged to form hodoscopes and sandwiched between layers of iron converter. The useful area of the spectrometer is about 1 m2. Pulse-height analysis is performed on each of the 648 counters with 12-bit ADCs. Photon position is determined using the center of gravity of the shower amplitudes in the hodoscope counters. To eliminate ambiguities in multi-photon events, the showers are measured in three 120° projections. The total thickness of the spectrometer is 20 r.l. of steel in the beam direction. This provides total absorption of photons and electrons with an energy up to 1000 GeV. The characteristics of the spectrometer as used in experiments at the 70 GeV IHEP accelerator are described.

Various application areas of presentation graphics and a number of requirements to them in the field of experimental high energy physics are considered. A pipeline model of the presentation graphics software for the applied graphics system and functional capabilities of the graphics package ATOM'84 are discussed.

A scintillation counter hodoscope was used to study the characteristics of electromagnetic showers with energies up to 40 GeV. The energy release in the shower is found to decrease exponentially with distance from the axis of the shower and to be localized within a radius of 1 cm. The position of the photon at the face of a scintillation counter hodoscope spectrometer can be determined with an accuracy of a few millimeters, using the center of gravity of the amplitudes from the counters.

The A -dependence of J/ψ inclusive production by 43 GeV/ c π − -mesons was measured to be σ = (18 ± 6) A (0.92±0.06) nb/nucleus for x > 0.

Results of the experimental study of inclusive φ meson production off berillium nuclei by 70 GeV/ c protons in the beam fragmentation region x > 0.41 are presented. Fitting of the measured differential cross sections to the forms d σ d x ∼ (1 − x) n x and d σ d p 2 t ∼ exp (−bp 2 t ) gives the parameters n = 6.0 ± 1.7 and b = (2.4 ± 0.7) (GeV/ c ) −2 . In the framework of a quark-parton model the measured φ meson x -distribution suggests that in the region of x > 0.41 nearly 90% of the φ mesons are produced via a strange sea quark fusion. The ratio of the OZI-forbidden and OZI-allowed transition coupling constants has been found to be ten times smaller than the same ratio calculated from the partial decay widths. The total inclusive cross section is estimated to be σ (pN → φ X) = (0.7 ± 0.2) × 10 −27 cm 2 .

The differential cross sections d σ d x and d σ d p t 2 of inclusive J/ψ production by 43 GeV/ c π − off Be, Cu and W nuclei have been measured. Fitting d σ d p t 2 ∼ A α (p t 2 ) we observed the increase of α with p t 2 .