Interstrip resistance of a semiconductor microstrip detector

In this work the interelement (interstrip) resistance of the microstrip detector is studied. A few detectors with a different construction are investigated. The dependence of the interstrip resistance on the dose of detector irradiation with electrons is obtained. The possibility of application interstrip resistance measurement for the determination of the good strip yield is shown

Radiation Tolerance of Single-Sided Microstrip Detector with Si3N4Si_{3}N_{4} Insulator

The ALICE Collaboration is investigating the radiation tolerance and operation of silicon microstrip detectors for the inner tracking system. Detectors with and without an additional layer of Si3N4 insulator were made in one set, using the same thickness of SiO2 insulator. Measurements were made on both types of detectors after irradiation with 20 MeV electrons, using doses up to 2Mrad. The additional Si3N4 layer allows a coupling capacitor breakdown voltage larger than 100 V and capacitor yield larger than 99 percent. However, the leakage current for detectors with double layer insulator is about 20 nA per strip while the leakage current for the single layer SiO2 insulated detectors is only 0.5 nA. The 20 nA leakage current leads to 450 electrons noise when the ALICE 128C electronics with a peaking time of 1.4 microseconds is used. At a 1 nA leakage current the noise is 100 electrons. The ENC for an input capacitance of 5 pF is 300 electrons. Since all detectors show an increased leakage current after irradiation, the difference between the single and duoble layer insulation detectors becomes negligible when doses of the order of several hundreds of krad are applied

Magnetizing of Finemet-type alloys by magnetization rotation in weak fields

Magnetic properties of functional magnetic materials depend on the magnetization processes nature. Creation of amorphous and nanocrystalline alloys using the rapid quenching technology is the result of the latest advances in magnetic materials area. Although significantly different in structure, they show excellence properties. In this paper we will investigate the magnetization properties of the Finemet-type nanocrystalline alloys in the range of their initial permeability formation. We will show that due to low level of effective magnetic anisotropy, even in weak fields, magnetization can occur through reversible, hysteresis-free rotation of the domain's magnetization vector. © Published under licence by IOP Publishing Ltd.Ministry of Science and Higher Education of the Russian Federation: 3.6121.2017/8.9, 4.9541.2017/8.9This work was supported by the Ministry of Science and higher Education and of the Russian Federation in the framework of state tasks No. 3.6121.2017/8.9 and No. 4.9541.2017/8.9

Kinematic Viscosity of Melt Prepared from an Amorphous Fe72.5Cu1Nb2Mo1.5Si14B9Ribbon

In this work, the viscosity of a melt prepared by melting an amorphous ribbon of Fe72.5Cu1Nb2Mo1.5Si14B9 alloy was studied. The amorphous ribbon was produced by rapid quenching of the melt, which was preheated at a temperature above (overheated mode) and below (not overheated mode) critical temperature Tk . A hysteresis loop was found in the temperature dependence of viscosity, the widest part of which falls on a temperature from 1670 K to Tk = 1760 K. In this temperature range, the melt has the highest activation energy and the largest cluster size. It has been proven that the melt viscosity increases with decreasing cluster size. In the low-temperature region, an overheated melt has the highest viscosity and the smallest cluster size comparable to the atomic size. It is shown that the heredity of the structure is preserved in the melt from the amorphous ribbon despite a number of structural transitions. © Published under licence by IOP Publishing Ltd

Permeability of Magnetic Cores with Air Gaps

The influence of the geometric dimensions of the cut core and the number and size of air gaps on the effective permeability was investigated. Using dimensional analysis, an equation was obtained that relates the permeability of the cut core to the simplest dimensionless combination of the mean magnetic flux length l, single air gap length lg1, the cross-sectional area S of the core, and gap number ng . Permeability calculated from the geometric parameters of the cut core was compared with the effective permeability obtained using a two-dimensional FEMM simulation. Simulation has shown that the equation derived from dimensional analysis provides the best fit. The influence of each significant parameters l, lg1, ng, and S on cut core permeability is demonstrated. Experimental results have shown that an equation derived from dimensional analysis can be used to predict cut core permeability. In this case, one should take into account the residual air gap that forms after cutting the core. A method for assessing the residual air gap is proposed. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Assessment of state services quality and availability in the socio-cultural sphere

© 2016, Econjournals. All rights reserved.The relevance of the presented research is caused by distribution of independent tools to assess public administration of the socio-cultural sphere by public nongovernmental organizations and scientific institutes. The objective of the paper is to develop a technique to assess quality and availability of state services in the socio-cultural sphere as components of public administration. An institutional approach has become a leading one; it allows to consider state services quality and availability assessment in the socio-cultural sphere as a complex indicator of the content quality of a resulting effect and quality of services obtained; it is also connected with the comfort of service rendering and their availability for consumers. The elaborated technique of state services quality and availability assessment in the socio-cultural sphere includes the following criteria: The level of state services quality; the level of state services availability; the level of trust that consumers have in service providers. The technique is directed to identify effective measures to provide consumers with available and high-quality state services in the socio-cultural sphere rendered by state bodies and their departments according to the results of a calendar year

CaloCube: a novel calorimeter for high-energy cosmic rays in space

In order to extend the direct observation of high-energy cosmic rays up to the PeV region, highly performing calorimeters with large geometrical acceptance and high energy resolution are required. Within the constraint of the total mass of the apparatus, crucial for a space mission, the calorimeters must be optimized with respect to their geometrical acceptance, granularity and absorption depth. CaloCube is a homogeneous calorimeter with cubic geometry, to maximise the acceptance being sensitive to particles from every direction in space; granularity is obtained by relying on small cubic scintillating crystals as active elements. Different scintillating materials have been studied. The crystal sizes and spacing among them have been optimized with respect to the energy resolution. A prototype, based on CsI(Tl) cubic crystals, has been constructed and tested with particle beams. Some results of tests with different beams at CERN are presented.Comment: Seven pages, seven pictures. Proceedings of INSTR17 Novosibirs

Quantum symmetry, the cosmological constant and Planck scale phenomenology

We present a simple algebraic argument for the conclusion that the low energy limit of a quantum theory of gravity must be a theory invariant, not under the Poincare group, but under a deformation of it parameterized by a dimensional parameter proportional to the Planck mass. Such deformations, called kappa-Poincare algebras, imply modified energy-momentum relations of a type that may be observable in near future experiments. Our argument applies in both 2+1 and 3+1 dimensions and assumes only 1) that the low energy limit of a quantum theory of gravity must involve also a limit in which the cosmological constant is taken very small with respect to the Planck scale and 2) that in 3+1 dimensions the physical energy and momenta of physical elementary particles is related to symmetries of the full quantum gravity theory by appropriate renormalization depending on Lambda l^2_{Planck}. The argument makes use of the fact that the cosmological constant results in the symmetry algebra of quantum gravity being quantum deformed, as a consequence when the limit \Lambda l^2_{Planck} -> 0 is taken one finds a deformed Poincare invariance. We are also able to isolate what information must be provided by the quantum theory in order to determine which presentation of the kappa-Poincare algebra is relevant for the physical symmetry generators and, hence, the exact form of the modified energy-momentum relations. These arguments imply that Lorentz invariance is modified as in proposals for doubly special relativity, rather than broken, in theories of quantum gravity, so long as those theories behave smoothly in the limit the cosmological constant is taken to be small.Comment: LaTex, 19 page

Comparison of relativity theories with observer-independent scales of both velocity and length/mass

We consider the two most studied proposals of relativity theories with observer-independent scales of both velocity and length/mass: the one discussed by Amelino-Camelia as illustrative example for the original proposal (gr-qc/0012051) of theories with two relativistic invariants, and an alternative more recently proposed by Magueijo and Smolin (hep-th/0112090). We show that these two relativistic theories are much more closely connected than it would appear on the basis of a naive analysis of their original formulations. In particular, in spite of adopting a rather different formal description of the deformed boost generators, they end up assigning the same dependence of momentum on rapidity, which can be described as the core feature of these relativistic theories. We show that this observation can be used to clarify the concepts of particle mass, particle velocity, and energy-momentum-conservation rules in these theories with two relativistic invariants.Comment: 21 pages, LaTex. v2: Andrea Procaccini (contributing some results from hia Laurea thesis) is added to the list of authors and the paper provides further elements of comparison between DSR1 and DSR2, including the observation that both lead to the same formula for the dependence of momentum on rapidit