Avalanche silicon photodiode have been developted for near ir, visible, UV and VUV light range. External quantum efficiency have been studied in 114 - 170 abd 210 - 1100nm range. It is demonstrated that photodiode reach from 29 to 9300 electrons/photon on 160 nm with bias voltage of 190 and 303 v respectively.

The possibility to increase the responsivity of 4H-SiC p+– n –n+ - photodiodes by varying the thickness of the p+ - epilayer has been studied. It is shown that the thinning of the upper epilayer by RIE with the use of metal contacts as a mask makes it possible to control both the maximum responsivity and the spectral dependence of the responsivity of photodiodes and does not lead to degradation of dark electrical characteristics.

The article considers the architecture of the ventilation control system for underground mining enterprises, equipped with a digital twin with online functions such as simulation modeling and predictive analytics. The system is focused on the main fan unit (MFU) control taking into account changing parameters of external air supplied to mine shafts. In contrast to the existing ones, the proposed method of control takes into account the influence of these parameters on changes in the total volume of natural draught, on which the total volume of air supplied to the mine (mine) depends. It is known that ventilation systems of such enterprises consume from 30 to 50 % of all electricity consumed for the mining process. In this regard, the proposed control models can be used to optimize energy costs and energy savings in ventilation. The Internet of things (IoT) InfluxData of stack TICK is offered for the realization. The offered architecture of cyber-physical system (CPS) consists of four subsystems: physical object subsystem, network and computing infrastructure IoT, digital twin, user interface. Architecture of CPS provides data processing from energy meters, control controllers and sensors of air environment parameters, implemented in blocks of on-line and off-line calculations. The digital twin of the ventilation system is made with the use of a time series database and a database of attributes that store information on changes in equipment parameters by time, air indicators, performance indicators, statistics on accidents and fan runtime, CPS characteristics, etc. CPS of the given architecture means connection of additional data sources, providing calculations of rational volumes of air delivery taking into account safety norms and requirements of energy efficiency.

The external quantum yield of silicon avalanche photodiode in the wavelength range of 120-170 nm was performed. It was shown that the engineered avalanche photodiode has the external quantum yield of 24-150 electron/proton under reverse bias voltage of 230-345 V, respectively. The testing of worked out avalanche photodiode by means of pulse flash of 280 and 340 nm wavelength demonstrates the speed, corresponding to the bandwidth not less than 25 MHz.

Abstract The influence exerted by the carrier concentration in the range (1–50) × 10^14 cm^–3 in n -4 H -SiC chemical-vapor deposited (CVD) epitaxial layers on the spectral characteristics of UV photodetectors with Cr Schottky barriers in the range of 200–400 nm is revealed and explained in terms of the photoconductivity theory. Schottky barriers with a Cr film thickness of 20 nm and diameter of 8 mm are formed by thermal evaporation in vacuum through masks. A noticeable effect of the carrier concentration in the CVD epitaxial layers on the spectral characteristics of photodetectors upon heating to 200°C is also observed and accounted for by a difference between the generation-recombination processes. The irradiation of photodetectors with 15-MeV protons at a fluence of 4 × 10^12 cm^–2 and a temperature of 200°C leads to an increase in the quantum efficiency as compared to samples irradiated in similar modes at 25°C. This is indicative of an increase in the radiation hardness and service life of 4 H -SiC devices at elevated temperatures.

The task of the research is to overview detector types for monitoring electons from a tritium beta decay in a sterile neitrino exploration. A new ASPD (avalanche silicon precision detector) detector was prefered because of 2.5E7 count rate benefits with a spectrometric opportunity at the room temperature with an active area of 0.785mm2.

Представлены результаты моделирования черенковского излучения широких атмосферных ливней (ШАЛ), порожденных космическими гамма-квантами и протонами космических лучей. Для наблюдений на высоте 2 и 5 km над уровнем моря рассчитана спектральная плотность черенковского излучения ШАЛ в диапазоне 240−700 nm при энергиях первичных частиц 3GeV−10 TeV. Отношение количества фотонов черенковского излучения ШАЛ в оптическом и ультрафиолетовом (УФ) диапазоне существенно зависит от типа первичной частицы, поэтому измерение и анализ этого отношения может применяться для выделения гаммасобытий из фона, создаваемого частицами космических лучей. Использование детектирующих элементов на основе специализированных кремниевых фотоумножителей, обладающих высокой чувствительностью в УФ диапазоне, позволяет существенно увеличить продолжительность рабочего цикла черенковского гаммателескопа за счет наблюдений в лунные ночи. При использовании в телескопах черенковской гаммаобсерватории ALEGRO разработанных в ФТИ им. А.Ф. Иоффе кремниевых лавинных умножителей (SiPM), порог регистрации гамма-событий только на основе измерений в УФ диапазоне составит около 40GeV на высоте 5 km и около 80GeV на высоте 2 km.

Cherenkov emission of extensive air showers (EAS) from cosmic gamma rays and cosmic-ray protons has been modelled. Spectral density of such emission in the 240–700 nm band has been determined for 3 GeV–10 TeV primaries of both sorts. It has been shown that the ratio of EAS Cherenkov emission fluxes in the optical and ultraviolet (UV) bands substantially depends on the sort of the primary, so the ratio can be employed to select gamma-ray events from the background produced by cosmic rays. Detection of EAS Cherenkov emission with specialized silicon photomultipliers sensitive in the UV band would allow one to substantially extend the duty cycle of a Cherenkov gamma-ray telescope, as it would be possible to observe the showers during moonlit nights. The UV-sensitive silicon photomultipliers developed at the Ioffe Institute would allow to detect gamma-ray-induced EAS at the Cherenkov gamma-ray observatory ALEGRO over a threshold of about 40 GeV at 5 km above sea level and about 80 GeV at 2 km above sea level.

Рассмотрен новый вид технических средств пожарной сигнализации - извещатели пожарные мультикритериальные (ИПМ). Приведена классификация этих извещателей в России и за рубежом. Предложено при оценке эффективности функционирования многоблочного ИПМ учитывать не толко характеристики обнаружения, но и его аппаратурную надежность. Получено математическое выражение для оценки этой эффективности ИПМ; проведен его численный анализ. Показана возможность оптимизации конструкции извещателей данного вида с использованием введенного параметра.

Problems of the origin and age of planation surfaces in the peninsular block of Hindustan are discussed alongside a morphostructural analysis of the area. It is noted that the river valleys are very ancient and are related to regional fractures. The shore line of Hindustan reveals sea-level fluctuations and tectonic movements of the coast in Pleistocene. A morphostructural classification of the relief is suggested.

Описано изготовление чип-анализатора на основе полидиметилсилоксана и стекла. Изучены возможности обработки поверхности канала чипа атмосферной плазмой и додецилсульфатом натрия, используемым в качестве добавки к рабочему буферу. Оценена скорость электроосмотического потока. На модельной смеси катехоламинов выявлено влияние модификации поверхности каналов микрочипа на эффективность и факторы разрешения. Найдены способы повышения чувствительности электрохимической ячейки; выявлены возможности on-line концентрирования в чип-формате. Достигнут предел детектирования катехоламинов 10-6 10-7 г/мл.