[en] Several methods of collecting light on scintillation counters using WLS fibers and WLS bars were studied. Nearly 20 prototype counters with different designs and with sizes ranging from 14x11x1.3cm³ to 105x60x1.3cm³ have been tested using cosmic muons and radioactive source. The efficiency of light collection on number of photoelectrons, uniformity of response, and time resolution have been measured. Test results for two new designs of light collection from scintillator based on WLS fibers around perimeter of scintillator plate and WLS fibers placed in machined on scintillator plate deep grooves are presented. Two out of the studied designs have been chosen as the basic options for the D0 muon system upgrade: light collection using two WLS bars for the forward muon scintillation counters and light collection using WLS fibers in deep grooves on scintillator for central area muon counters

[en] Several methods of collecting light on scintillation counters using WLS fibers and WLS bars were studied. Nearly 20 prototype counters with different designs and with sizes ranging from 14x11x1.3 cm³ to 105x60x1.3 cm³ have been tested using cosmic muons and radioactive source. The efficiency of light collection on number of photoelectrons, uniformity of response, and time resolution have been measured. Test results for two new designs of light collection from scintillator based on WLS fibers around perimeter of scintillator plate and WLS fibers placed in machined on scintillator plate deep grooves are presented. Two out of the studied designs have been chosen as the basic options for the Doe muon system upgrade: light collection using two WLS bars for the forward muon scintillation counters and light collection using WLS fibers in deep grooves on scintillator for central area muon counters

[en] The driving system of a Moessbauer spectrometer is described. The system comprises a minivibrator, a digital generator of the reference velocity signal, and circuits for controlling the vibrator. The reference velocity signal is stored by the control computer in an intermediate storage. The feedback in the control circuits includes correction for nonlinearity of the driving facility. A Moessbauer spectrometer which is equipped with this driving system exhibits a velocity scale nonlinearity below 0.1%. The resonance line width for sodium nitroprusside is 0.27 ± 0.01 mm/s. (author). 6 figs., 8 refs

[en] A homogeneous planar photoconverter (PC) of a new type based on a multi-junction n-p-p⁺ -n-p-p⁺ - -n-p-p⁺ semiconductor structure was proposed. This semiconductor structure is a cascade PC consisting of several exposed PCs connected in series, with the light passing through the previous semiconductor layers. A theory was worked out, and the limiting values of photoelectric and energy characteristics of high-voltage devices that convert monochromatic and solar light were developed. These values include optimum values of the thickness and the number of the PCs applied onto the base PC, spectral selectivity, voltage-current characteristics, and performance. The no-load voltage rises practically in a linear fashion when the number of cells in the cascade increases. With an optimum number of cells, the peak performance values reach their peaks and considerably exceed the performance of the base PC, especially at a low carrier collection coefficient in the base PC. (authors)

[en] A PC-AT based Moessbauer spectrometer is described. It consists of a data acquisition system, a velocity generator, a driving unit, a scintillation detector, a high voltage power supply, a single channel analyzer and a ⁵⁷Co source in a Rh matrix. The driving system consists of an electromechanical vibrator, a control electronic system and a digital reference velocity generator. The velocity interval of the driving system is ±70 mm/sec. The scintillation detector using a YAlO₃:Ce crystal provides a high resolution for soft gamma and X-ray radiation, which guarantees successful application in Moessbauer spectroscopy under high counting rates. The total nonlinearity is for a α-Fe sample better than 0.1%. (Z.S.) 2 tabs., 6 figs., 9 refs

[en] The article is dedicated to the development and investigation of conditions for obtaining the aggregate stable colloid solutions of magnetite – magnetic fluids. The developed method differs from the known ones and involves new ways of producing and stabilizing magnetic nanoparticles with a narrow particle size distribution. (paper)

[en] A Cherenkov counter for bunch intensity measurements in slow extracted beams from the IHEP accelerator is described. The dynamic range is from 1 to 10⁶ particles/bunch and bunch frequency is up to 6·10⁶ Hz. Cherenkov light is detected by XP 2020 PMT. Photomultiplier signal pulse height and delay were measured as a function of high voltage from 0.8 to 2.7 kV using green and blue LEDs. Results of the counter calibration in the 50 GeV proton beam are presented. The model used to fit the counter pulse height spectra is discussed.

[en] In this work, the results of the measurements of characteristics of 40-cm and 2-m scintillation counters irradiated by a particle beam with a momentum of 7 GeV/c from the accelerator of the Institute for High Energy Physics are presented. The scintillators used in counters are BC-404 and BC-408 scintillators. The counters are viewed from both ends by R1828-01 photomultiplier tubes. The PMT signal spectra are well described by a convolution of the Landau and Gaussian distributions. Their width is determined mainly by fluctuations of ionization energy losses. The time distributions of the signals obey the Gaussian law. For the 40-cm counter, the time resolution is σ(T) = 88 ps; for the 2-m counter, it varies from 120–160 ps in its center to ~100 ps near the end.

[en] A hadron calorimeter in which scintillators are arranged nearly parallel to the incident particle direction and light is collected by optical fibres with WLS, has been built. The iron absorber plates are of the tapered shape to fit a barrel structure of the collider geometry. The performance of the calorimeter studied with hadron beam is presented as a function of tilt angle without and with electromagnetic calorimeter in front of the hadron one. (orig.)

[en] This article describes a process of calculating a certain complex information security system (CISS) reliability using the example of the technospheric security management model as well as ability to determine the frequency of its maintenance using the system reliability parameter which allows one to assess man-made risks and to forecast natural and man-made emergencies. The relevance of this article is explained by the fact the CISS reliability is closely related to information security (IS) risks. Since reliability (or resiliency) is a probabilistic characteristic of the system showing the possibility of its failure (and as a consequence - threats to the protected information assets emergence), it is seen as a component of the overall IS risk in the system. As it is known, there is a certain acceptable level of IS risk assigned by experts for a particular information system; in case of reliability being a risk-forming factor maintaining an acceptable risk level should be carried out by the routine analysis of the condition of CISS and its elements and their timely service. The article presents a reliability parameter calculation for the CISS with a mixed type of element connection, a formula of the dynamics of such system reliability is written. The chart of CISS reliability change is a S-shaped curve which can be divided into 3 periods: almost invariable high level of reliability, uniform reliability reduction, almost invariable low level of reliability. Setting the minimum acceptable level of reliability, the graph (or formula) can be used to determine the period of time during which the system would meet requirements. Ideally, this period should not be longer than the first period of the graph. Thus, the proposed method of calculating the CISS maintenance frequency helps to solve a voluminous and critical task of the information assets risk management. (paper)