N. Egorov

Fabrication of ultrafine silicon layers on sapphire

The effect of energy, dosage, and temperature of irradiation of silicon-on-sapphire structures by Si+ ions, as well as parameters of recrystallization annealing, on crystallinity of silicon film is shown. Implantation conditions and recrystallization annealing conditions are determined.

The NUCLEON experiment: The current status

The main purpose of the NUCLEON experiment is direct measurements of the energy spectra of cosmic rays in the range 1011–1015 eV with the use of the lightweight facility during a prolonged orbital flight. The energy is determined using a technique based on the measurement of the spatial density of secondary particles produced in the initial event of inelastic interaction. The schematic diagram of the NUCLEON facility, the current status of the project, the results of testing the prototype, and plans are presented.

An Instrument to Measure Elemental Energy Spectra of Cosmic Ray Nuclei up to 1016 eV

Abstract A longstanding goal of cosmic-ray research is to measure the elemental energy spectra of cosmic rays up to and through the “knee” (≈3×10 15 eV). It is not currently feasible to achieve this goal with an ionisation calorimeter because the mass required to be deployed in Earth orbit is very large (at least 50 tonnes). An alternative method is presented. This is based on measuring the primary particle energy by determining the angular distribution of secondaries produced in a target layer using silicon microstrip detector technology. The proposed technique can be used over a wide range of energies (10 11 –10 16 eV) and gives an energy resolution of 60% or better. Based on this technique, a design for a new lightweight instrument with a large aperture (KLEM) is described.

Defect formation and recrystallization mechanisms in silicon-on-sapphire films under ion irradiation

The effect of the parameters (energy, dose) of the irradiation of silicon-on-sapphire (SOS) structures with ions Si+ ions on the quality of the silicon-film crystal structure after solid-phase epitaxial recrystallization and annealing is studied. It is shown that the most efficient mechanism of crystal-structure recovery is recrystallization from the silicon surface layer which is a seed.

The effect of camphor on bacterial bioluminescence

SummaryThe inhibitory effect of camphor on bioluminescence of both bacteria and bacterial luciferase has been examined. The camphor has been shown to be a substrate of cytochrome P-450 of the luminous bacteria Photobacterium fischeri. The inhibition of the luminescence reaction provided evidence for the competitive nature of the interaction of camphor and aliphatic aldehyde at the binding site for luciferase. Camphor is also supposed to interact with P-450. The findings indicate that the hydroxylation process of camphor affects the kinetics of the luminescence.

A vertex microstrip detector of the SVD setup for experiments on the IHEP accelerator

A precision vertex microstrip detector has been developed for the spectrometer with a vertex detector (SVD) setup on which the properties of hadrons and short-lived unstable particles are investigated on the accelerator of the Institute for High Energy Physics. The structure and the design of the main detector components—microstrip sensors and an active target—are presented, as well as techniques for manufacturing them. The readout electronics, the data acquisition system, and its software are also described. The accuracy in determining the vertex position is 70–250 µm along the beam axis and 8–15 µm in a transverse direction at a throughput of 500–1000 events/s.

Investigation of the internal amplification effect in planar p-silicon structures

The results of investigation of n++p+pp+ silicon detector structures manufactured from p silicon are presented. These detectors demonstrate the effect of internal amplification of a signal (with a gain of 20) with retained properties of the detector as a spectrometric device. An efficient lowering of the energy level for the detected ionizing radiation is demonstrated.

The Distribution of an Electric Field in p-n Junctions of Silicon Edgeless Detectors

Development of silicon edgeless detectors started in 2004 and was motivated by preparations for the total elastic and diffractive cross-section measurement (TOTEM) experiment at the Large Hadron Collider (LHC) at CERN. In the context of this experiment, it would be necessary to detect protons scattered at ultimately small angles with respect to the LHC proton beam, which brings about a limitation imposed on the maximum distance between the beam and the sensitive region of the detector. In order to solve this problem, a new type of silicon detector (edgeless detectors) was developed; these detectors have the structure, which controls the distribution of the current near the edge of the p-n junction. In this paper we report the results of studying the distribution of the potential and an electric field in the region of the cut edge in the silicon edgeless detectors; the models, which account for the obtained results, as well as their consistency with current-voltage characteristics of silicon edgeless detectors developed for the TOTEM experiment, are discussed.

Resistance of silicon planar detectors to X-rays

We investigated the effect of X-rays with a dose of a few kilogrey on the characteristics of silicon planarp+−n-detectors. The values of noise in terms of charge and the voltage-current and voltage-capacitance characteristics were analyzed. We determined the X-ray dose, for which the noise 1/f was generated. Charge accumulation in the protective oxide was responsible for this noise and affected the volt-ampere and volt-farad detector characteristics.