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S. N. Filippov

Publications and source records attributed to S. N. Filippov.

46 records · Page 3Linked to original sources
arXiv2009

RETGEM with polyvinylchloride (PVC) electrodes

This paper presents a new design of the RETGEM (Resistive Electrode Thick GEM) based on electrodes made of a polyvinylchloride material (PVC). Our device can operate with gains of 10E5 as a conventional TGEM at low counting rates and as RPC in the case of high counting rates without of the transit to the violent sparks. The distinct feature of present RETGEM is the absent of the metal coating and lithographic technology for manufacturing of the protective dielectric rms. The electrodes from PVC permit to do the holes by a simple drilling machine. Detectors on a RETGEM basis could be useful in many fields of an application requiring a more cheap manufacturing and safe operation, for example, in a large neutrino experiments, in TPC, RICH systems.

physics.ins-det↗
arXiv2009

Wire GEM detector

A wire GEM (WGEM) detector with a gas gap between meshes was constructed. The detector provides the amplification 5x10E5 for the gas mixture of Ar +20% CO2 at atmospheric pressure. As compared with well-known GEM detectors produced by perforation the plastic plate metalized on both sides the WGEM does not suffer from breakdowns between its electrodes and the effect of accumulation of charges on holes walls is absent. As a result the WGEM has high reliability and stability.

physics.ins-det↗
arXiv2009

Distances between quantum states in the tomographic-probability representation

Distances between quantum states are reviewed within the framework of the tomographic-probability representation. Tomographic approach is based on observed probabilities and is straightforward for data processing. Different states are distinguished by comparing corresponding probability-distribution functions. Fidelity as well as other distance measures are expressed in terms of tomograms.

quant-ph↗
arXiv2009

Probability representation and quantumness tests for qudits and two-mode light states

Using tomographic-probability representation of spin states, quantum behavior of qudits is examined. For a general j-qudit state we propose an explicit formula of quantumness witnetness whose negative average value is incompatible with classical statistical model. Probability representations of quantum and classical (2j+1)-level systems are compared within the framework of quantumness tests. Trough employing Jordan-Schwinger map the method is extended to check quantumness of two-mode light states.

quant-ph↗
arXiv2009

Chebyshev polynomials and Fourier transform of SU(2) irreducible representation character as spin-tomographic star-product kernel

Spin-tomographic symbols of qudit states and spin observables are studied. Spin observables are associated with the functions on a manifold whose points are labelled by spin projections and 2-sphere coordinates. The star-product kernel for such functions is obtained in explicit form and connected with Fourier transform of characters of SU(2) irreducible representation. The kernels are shown to be in close relation to the Chebyshev polynomials. Using specific properties of these polynomials, we establish the recurrence relation between kernels for different spins. Employing the explicit form of the star-product kernel, a sum rule for Clebsch-Gordan and Racah coefficients is derived. Explicit formulas are obtained for the dual tomographic star-product kernel as well as for intertwining kernels which relate spin-tomographic symbols and dual tomographic symbols.

quant-ph↗
arXiv2009

Spin tomography and star-product kernel for qubits and qutrits

Using the irreducible tensor-operator technique, we establish the relation between different forms of spin tomograms. Quantizer and dequantizer operators are presented in simple explicit forms and are specified for the low-spin states. The kernel of the star-product is evaluated for qubits and qutrits and its connection with a generic formula is found.

quant-ph↗
arXiv2009

Quantumness tests and witnesses in the tomographic-probability representation

In view of the tomographic-probability representation of quantum states, we reconsider the approach to quantumness tests of a single system developed in [Alicki and Van Ryn 2008 J. Phys. A: Math. Theor. 41 062001]. For qubits we introduce a general family of quantumness witnesses which are operators depending on an extra parameter. Spin tomogram and dual spin tomographic symbols are used to study qubit examples and the test inequalities which are shown to satisfy simple relations within the framework of the standard probability theory.

quant-ph↗
arXiv1999

Formation of Centauro and Strangelets in Nucleus-Nucleus Collisions at the LHC and their Identification by the ALICE Experiment

We present a phenomenological model which describes the formation of a Centauro fireball in nucleus-nucleus interactions in the upper atmosphere and at the LHC, and its decay to non-strange baryons and Strangelets. We describe the CASTOR detector for the ALICE experiment at the LHC. CASTOR will probe, in an event-by-event mode, the very forward, baryon-rich phase space 5.6 < η< 7.2 in 5.5 A TeV central Pb + Pb collisions. We present results of simulations for the response of the CASTOR calorimeter, and in particular to the traversal of Strangelets.

hep-ph↗
arXiv1999

CASTOR: The ALICE forward detector for identification of Centauros and Strangelets in Nucleus-Nucleus Collisions at the LHC

The physics motivation for a very forward detector for the ALICE heavy ion experiment at the CERN LHC is discussed. A phenomenological model describing the formation and decay of a Centauro fireball in nucleus-nucleus collisions is presented. The CASTOR detector which is aimed to measure the hadronic and photonic content of an interaction and to identify deeply penetrating objects in the very forward, baryon-rich phase space 5.6 < eta < 7.2 in an event-by-event mode is described. Results of simulations of the expected response of the calorimeter, and in particular to the passage of strangelets, are presented.

hep-ex↗