Vitaly Smirnov

The kinetics and energetics of chromium-sensitized neodymium luminescence of several codoped gallium garnets (YAG, YSGG, GGG, and GSGG) have been measured and interpreted in terms of microscopic physical-energy-transfer mechanisms. Sensitized luminescence in YAG and in YSGG is well described by the static energy-transfer process; a migration-accelerated energy transfer process is determined to be operative in GGG and GSGG crystals.

Abstract There are many applications for mid‐infrared light sources which has stimulated intensive research into the physics and technology of narrow gap materials and devices. In this article we give an overview of the development of mid‐infrared LEDs and diode lasers being studied in our laboratory. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

We present measurements of the reduction of light output by plastic scintillators irradiated in the CMS detector during the 8 TeV run of the Large Hadron Collider and show that they indicate a strong dose rate effect. The damage for a given dose is larger for lower dose rate exposures. The results agree with previous measurements of dose rate effects, but are stronger due to the very low dose rates probed. We show that the scaling with dose rate is consistent with that expected from diffusion effects.

The FELIX collaboration had proposed the construction of a full-acceptance detector for the LHC. The primary mission of FELIX was the study of QCD: to provide comprehensive and definitive observations of a very broad range of strong-interaction processes. This document contains an extensive discussion of this physics menu. In a further paper the FELIX detector will be reviewed.

The parametric amplification of the radiation with fundamental frequency has been first observed by exposure of oxide glass to radiations with fundamental and doubled frequencies. The parametric amplification of signal is investigated both in the absence of the initial χ(2)-gratings and in the presence of the initial photoinduced χ(2)-gratings in glass. Some properties of this amplification have been studied. An explanation of the observed process of parametric amplification that takes into account the coherent photogalvanic effect is presented.

Photoconductivity and photoluminescence of HgCdTe-based nanostructures with 50 to 200 nm-wide potential wells were studied. The structures were grown by molecular beam epitaxy on GaAs substrates, and emitted light with wavelengths 2.8–3.8 μm at 300 K. The luminescence properties of the nanostructures at low temperatures were found to be strongly affected by the effect of alloy disorder, which led to a substantial red-shift of the emission spectrum in relation to energy gap of the wells. This effect could be reduced by post-growth annealing of the structures, which also increased the luminescence intensity. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We review status and perspectives of the search of the η-mesic nuclei at the synchrotron NUCLOTRON. This article present the results obtained at the spectrometer “SCAN” and the plans to study the interaction of eta-meson with nucleon and modification of the particle properties in the nuclear matter.

Plastic scintillators are often used as detectors in High Energy Physics (HEP), but have insufficient radiation hardness. Organization of better light collection inside a single detector may prolong operation life of scintillators. A finger-strip plastic scintillator option has many advantages to keep the excellent detector performance at high luminosity. Measurements assigned to show an advantage of a stripped detector vs. the un-stripped one in the range of increased absorbed doses and the smallest dose rates have been performed. This method has proved to be a good upgrade strategy.

Algorithms using software transactional memory for implementing thread-safe associative arrays (a red-black tree, a hash table with open addressing based on the Hopscotch method hashing collision resolution) are proposed. The analysis of the efficiency of associative arrays with different number of involved threads and processor cores is given, comparison with data structures based on coarse-grained and fine-grained locks is given, algorithm selection recommendations for performing transactions are also formulated. The basics of software transaction memory, various policies for updating objects in memory and strategies for conflict detection are described. Various locking methods for using transactional memory implemented in the GCC 5.4.0 compiler are presented. The alternatives currently in use are briefly considered, advantages and disadvantages are also highlighted.

Infrared photoluminescence (PL) measurements were used to probe compositional disorder in semiconductor (Hg,Cd)Te alloy. PL was studied in Hg1−xCdxTe samples with x=0.38 and 0.57, fabricated by molecular beam epitaxy on GaAs substrates. Both as-grown and annealed in Hg vapor and in He atmosphere samples were studied. In all the samples, the PL peak energy was found to be red-shifted from the position of band-to-band recombination maximum expected from the energy gap of the material. The value of the shift depended on temperature. This effect was attributed to recombination of excitons localized at compositional fluctuations, and an analysis was carried out that provided a way for evaluation of a fluctuation measure. The amplitude of the fluctuations was shown to strongly decrease as a result of post-growth annealing.

The spatial distributions of photoinduced electric fields are calculated based on the model of the current mechanism of optical poling of isotropic media and the efficiencies of the main poling schemes differing in the geometry of crossing beams are estimated. It is shown that the volume optical poling in a certain interval of small angles of crossing beams is the most promising for producing homogeneously distributed photoinduced electric structures of a large size.

The giant increase of the absorption of the radiation with the doubled frequency in a region of high values of the optically-induced electric fields (about 105–106 V/cm) has been observed during the investigation of the optical poling process in germanium-silicate glass. The absorption suppresses the writing of the second-order susceptibility grating and leads to the restriction of the maximum efficiency of the photoinduced second harmonic generation in glass. We demonstrate that the observed effect is not anisotropic and may be considered as a consequence of a competition between the charge separation by the local trapping levels due to electrostricted photoinduced phonons and recombination diffusion of carriers.

Investigations of the photoluminescence of PbS-EuS superlattices deposited on (111)DaF2 substrates are presented.Quantum-size and deformation effects in photoluminescence spectra are observed.The strain-induced gap shift and valence-band offset is determined from experimental results.A strong stimulated photoluminescence with relatively low threshold was observed.It was found that the photocarriers generated in EuS barrier strongly affect the population of PbS subbands.

A readout box prototype for the CMS Hadron Forward calorimeter upgrade was built and tested in the CERN H2 beamline. The prototype was designed to enable simultaneous tests of different readout options for the four anode upgrade PMTs, new front-end electronics design and new cabling. The response of the PMTs with different readout options was uniform and the background response was minimal. Multi-channel readout options further enhanced the background elimination. Passing all the electronic, mechanical and physics tests, the readout box proved to be capable of providing the forward hadron calorimeter operational requirements in the upgrade era.

Plastic scintillators are very often used as detecting media in sampling calorimeters of High Energy Physics (HEP). Many modern HEP experimental installations are already operating or proposed to work at high luminosity. Plastic scintillators are the most sensitive part of such setups in terms of their radiation hardness. Improving the light collection from the most irradiated scintillators will ensure their long-term use at high luminosity. The experimental results of the measurements for different assemblies (scintillator SCSN-81 and the WLS fiber Y-11 electron-irradiated (E≈4 MeV) were obtained. Calculations of the light yields for different samples based on our experimental results show the possibility of increasing the radiation hardness of plastic scintillators inside the sampling calorimeter up to 20 Mrad.

It is demonstrated that the nonlinear photo-integrated micro- and nano-periodic second-order susceptibility lattices with very small amplitudes which were preliminarily recorded using bi-chromatic powerful laser light in amorphous glass materials can be increased up to some orders of magnitude under the action of a simple coherent monochromatic radiation. The optical increase of the small lattices takes place independent of the polarization and direction of propagation of the optical amplifying radiation and is achieved at various wavelengths. The observed phenomenon is not be explained only by nonlinear wave interaction in medium and also may be related to the microscopic asymmetry processes of the optical transitions between local centers in an isotropic medium that leads to the appearance and growth of the all-optically induced small micro- and nano-periodic electrical charges separations inside the sample. Possible mechanisms that may be responsible for the observed effects in the studied phosphate glasses are discussed.

Abstract The results of comparative studies of radiation resistance are discussed inthis paper for (9–12)Cr and (1–2)Mo steels obtained using three technologies of melting. The irradiation was performed in the temperature range 350–500°C and neutron fluence up to 4.5 × 10 26 m −2 . It is shown that Fe-12Cr steels exceed Fe-12Cr ones in radiation resistance. Electron microscopic studies of the irradiation samples showed that the reason for the difference is connected with α′-phase formation in 12Cr steel ♯ . The absence of α′-phase in 9Cr steel after irradiation made it possible to improve its radiation resistance due to the components variation and improving the melting technology. The annealing at 550°C of the irradiated Cr steels caused “curing” of the radiation defects and the recovery of mechanical properties. The repeated irradiation of the annealed steels did not change their radiation embrittlement.

The possibility for creation of the optical anisotropy with small periodicities up to nano-scale in amorphous materials is perspective in future for obtaining of different miniature elements for optoelectronics. In this paper the investigation results of the impact of rare-earth doping upon the process of the creation and also on the properties of the photo-induced micro-periodical anisotropy in different samples are presented. The influence of the variations of the chemical rare-earth components is analyzed and the physical mechanisms are discussed.

The volumetric anisotropic microlattices, all-optically integrated into different compound materials, are interesting for investigations since they are potentially perspective for optical micro- and nanoelectronic technologies. In this paper the peculiarities of the properties of the volumetric anisotropic microlattices in different compound materials are considered and the comparisons of the nonlinear processes of light-beams transformations in dependence on the concentrations of different chemical elements in investigated bulk samples are discussed.

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text A. P. Zhevlakov, V. A. Smirnov, I. V. Bagrov, S. A. Tulskii, and N. V. Vysotina, "Anomalies in the fluorescence of petroleum products excited by laser radiation," J. Opt. Technol. 66, 418- (1999) Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

The appearance of the photorefractive effect on all optical polling (OP) of a bulk glass is investigated. During OP, a refractive-index grating accumulates in the glass and radiation effectively diffracts through it. The theory of the self-diffraction of light has been developed and the resultant expression for the amplitude of the diffracted light has been deduced, considering the geometry of formation of the refractive-index grating in glass upon interaction of the intersecting Gaussian beams. The results of the experimental investigation of the diffraction of light on the photorefractive gratings induced in some oxide glasses have been presented. The experimental results obtained are in agreement with the theory, based on a model of formation of a spatially periodic electrostatic field in glass via the coherent photogalvanic effect. The phenomenon of light diffraction can be used to investigate the physical properties of all OP in different glass media and to search for new, effective photorefractive materials.

The peculiarities of the outside influences on the all-optical poling process and on the formed nonlinear optical structures of second-order polarizability are studied. The basic attention is given to considering the outside influences of the laser radiations with different powers and also the variations of temperature. The observed kinetics during the outside influence in the studied phosphate glass materials was investigated and it was shown the possibility of the sufficiently increase of the photo-integrated grating structures in the all-optical poling process by means of the outside thermal influence.

CMS hadron calorimeters (HB, HE, HO) have been in operation for several years and contributed substantially to the success of the CMS Physics Program. The endcap calorimeter HE suffered more radiation damage than anticipated causing rapid degradation of scintillator segments (tiles) which have a higher radiation flux from secondary particles than HB and HO. A proposal to upgrade of HE calorimeter will provide a solution for survivability at future LHC higher luminosity. A finger-strip plastic scintillator option has many advantages and is a lower cost alternative to keep the excellent HE performance at high luminosity. Measurements and simulations have been performed and this method is a good upgrade strategy. HE upgrade beyond phase 1. Finger scintillator option. S.V. Afanasiev, P. de Barbaro, A.Yu. Boyarintsev, I.F. Emeliantchik, I.A. Golutvin, B.V. Grinyov, Yu.V. Ershov, L.G. Levchuk , A.V. Litomin, A.I. Malakhov, P.V. Moisenz, V.F. Popov , N.M. Shumeiko, V.A. Smirnov, P.V. Sorokin, P.N. Zhmurin a Joint Institute for Nuclear Research, Dubna, Russia b National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine c Institute for Scintillation Materials National Academy of Sciences of Ukraine, Kharkov, Ukraine d National Center for Particle and High Energy Physics, Minsk, Belarus e University of Rochester, Rochester, USA Abstract CMS hadron calorimeters (HB, HE, HO) have been in operation for several years and contributed substantially to the success of the CMS Physics Program. The endcap calorimeter HE suffered more radiation damage than anticipated causing rapid degradation of scintillator segments (tiles) which have a higher radiation flux from secondary particles than HB and HO. A proposal to upgrade of HE calorimeter will provide a solution for survivability at future LHC higher luminosity. A finger-strip plastic scintillator option has many advantages and is a lower cost alternative to keep the excellent HE performance at high luminosity. Measurements and simulations have been performed and this method is a good upgrade strategy.CMS hadron calorimeters (HB, HE, HO) have been in operation for several years and contributed substantially to the success of the CMS Physics Program. The endcap calorimeter HE suffered more radiation damage than anticipated causing rapid degradation of scintillator segments (tiles) which have a higher radiation flux from secondary particles than HB and HO. A proposal to upgrade of HE calorimeter will provide a solution for survivability at future LHC higher luminosity. A finger-strip plastic scintillator option has many advantages and is a lower cost alternative to keep the excellent HE performance at high luminosity. Measurements and simulations have been performed and this method is a good upgrade strategy.

physica status solidi (b)Volume 130, Issue 1 p. K43-K45 Short Note The Generation of Stimulated Radiation and the High-Temperature Photoluminescence in CdXHg1−XTe Layers V. I. Ivanov-Omskii, V. I. Ivanov-Omskii Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorA. Sh. Mekhtiev, A. Sh. Mekhtiev Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorR. B. Rustamov, R. B. Rustamov Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorV. A. Smirnov, V. A. Smirnov Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this author V. I. Ivanov-Omskii, V. I. Ivanov-Omskii Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorA. Sh. Mekhtiev, A. Sh. Mekhtiev Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorR. B. Rustamov, R. B. Rustamov Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorV. A. Smirnov, V. A. Smirnov Scientific and Industrial Association for Space Research of Natural Resources, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this author First published: 1 July 1985 https://doi.org/10.1002/pssb.2221300150Citations: 3 prospekt Lenina 159, 370106 Baku, USSR. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume130, Issue11 July 1985Pages K43-K45 RelatedInformation

This paper theoretically discusses possible ways of increasing the efficiency of optical cooling accompanying anti-Stokes excitation of the fluorescence of solutions of complex molecules. It is concluded that it is promising for these purposes to use the "photoinduced" luminescence effect, which makes it possible to speed up the photoluminescence process without causing additional population of the excited states of the molecule. © 2004 Optical Society of America

Optical pumping of electrons in the non-magnetic alloys Hg0.31Cd0.69Te and Hg0.39Cd0.61Te at 4.2 K was studied by circularly polarized excitation with photon energy somewhat higher than the energy gap and compared with optical pumping efficiency for the semi-magnetic alloy Hg0.77Mn0.23Te with intermediate values of the band parameter. Spin relaxation times were estimated for semi-magnetic and non-magnetic alloys. The experimental values were compared with the theory of spin relation of electrons in semiconductors. The mechanism of spin relaxation in non-magnetic alloys with 0.61<x<0.69 at 4.2 K was shown to be the Bir-Aronov-Pikus electron-hole exchange interaction, while the electron spin relaxation in the semi-magnetic alloy goes through the electron-Mn2+ exchange interaction. Finally, the authors apply the optical pumping technique to evaluate some parameters of electron recombination through the deep impurity centres.

The following paper considers the process of classification of polydisperse free-flowing material according to granulometric composition using a gravitational air classificator.There were considered the problems of the purity of separation of polydisperse bulk materials and methods for increasing the degree of separation of particles.There were presented and analyzed obtained the results of the comparison, the data of experimental research and computer simulation of two-phase hydrodynamics flow by CFD methods.The versatility of this complex allowed carrying out simulation of the process using various parameters.As a result, were obtained optimal operating parameters, which were experimentally verified.Based on the obtained data as a result of numerical modelling, the possibility of increasing gas flow influence to the polydispersed material were found, as well as organization along the walls of coarse fraction downward flow by dint of the optimizing the devise design (specifically through the organization of additional inlets for airflow) were obtained.

The equilibrium energy-band diagram of a broken-gap p-GaInAsSb/p-InAs heterojunction was calculated by solving the Poisson equation with account of the charge of free carriers and ionized impurities and the built-in charge at the heterointerface. The quantum level energies were found within the quasi-classical approximation for electrons in the self-consistent potential well. The calculated energies are close to those observed in electroluminescence spectra of such heterojunctions.

The FELIX Collaboration proposes the construction of a full acceptance detector for the LHC, to be located at Intersection Region 4, and to be commissioned concurrently with the LHC. The primary mission of FELIX is the study of QCD: to provide comprehensive and definitive observations of a very broad range of strong-interaction processes. This document contains a description of the detector concept including details of the individual detector elements and their performance characteristics, an extensive discussion of the physics menu, and the plans for integration of FELIX into the collider lattice and physical environment.

Investigations of the nonlinear optical phenomenon of light parametrical down-frequency conversion which is appeared on micro-periodic nonlinear structures photo-integrated in volumetric optical isotropic medium on all-optical poling process are presented. The observed phenomenon is similar to the well known degenerate parametric conversion in square-nonlinear media such as the optical nonlinear crystals. Observations of the amplification of low light signals on the created micro-structured oxide glass materials and also the appearance of the photoelectric instability of the preliminarily induced optical anisotropy by illumination of medium with use the coherent monochromatic source are considered. The big growth of the intensity of small signal of the basic frequency radiation with time (a photo-induced amplification of light) has been detected in experiments with the influence upon amorphous optical material simultaneously by the weak probe radiation of the basic frequency and the strong radiation of the second harmonic. Various modes of the amplification of light signal in experimental samples were investigated in presence of the preliminary created photo-integrated nonlinear structures with different amplitudes and mechanisms of the occurrence of the parametric generation in photo-integrated structures with the existence of the non-steady regimes of signal amplification are discussed.

The processes and the properties of the creation of the photo-refractive Bragg gratings in center-symmetrical materials by considering of the coherent interactions of the laser radiations have been analyzed. Characteristic experimental results of the scattering and the diffraction of light on photo-refractive Bragg gratings in volumetric glass materials are considered and the possible mechanisms of the observed and investigated processes are discussed.

Theoretical consideration of the nonlinear conversion of light in photo-integrated micro- and nano-periodic susceptibility lattices which could be created in different isotropic materials is presented. The phenomena of the frequency doubling of light and the parametrical amplification of light in transformed isotropic medium are investigated according into account the realistic picture of the possible formation of the space structures of second order susceptibility with micro- and nanoperiodicities by action of the intersecting Gaussian beams of the fundamental and doubled harmonics of the mutualcoherent powerful laser radiation. The developed theory is based on a model of the formation of long-lived electrostatic field in isotropic material by means of the coherent photo-galvanic effect and gives the interesting peculiarities of processes of the frequency doubling and parametrical amplification of light which are connected with the formation of the long-lived susceptibility structures in volumetric media. In contrast to the well known nonlinear crystals, it has been demonstrated that in photo-integrated space-periodic susceptibility there is a possibility to obtain a new regime of twobeam frequency conversion of light. Fundamental properties of the phenomena have been studied and the possible mechanisms of processes are discussed.

Perspectives of photo-modification of different glass materials for creating of the optical frequency micro- and nanoconverters are considered. The experimental results of the nonlinear conversions of the visible laser radiation on the photo-integrated volumetric lattices of the second-order susceptibility, which were fabricated in isotropic glass materials by the action of the pulsed powerful bi-chromatic inter-coherent radiation of YAG:Nd laser, are presented. The experimental investigations of the frequency conversion of the light laser radiation have been performed in potentially perspective materials with variations of the chemical compounds of the fundamental matrix and also by the small changes of the additional doped concentrates. The separate attention was given to considering the samples with content of the rare-earth elements and the detailed analysis of the influence of the chemical compound was carried out.

Two CMS Endcap hadron calorimeters (HE) have been in operation for several years and contributed substantially to the success of the CMS Physics Program. The HE calorimeter suffered more from the radiation than it had been anticipated because of rapid degradation of scintillator segments (tiles) which have a high radiation flux of secondary particles. Some investigations of scintillators have shown that the degradation of plastic scintillator increases significantly at low dose rates. A proposal to upgrade up-grade the HE calorimeter has been prepared to provide a solution for survivability of the future LHC at higher luminosity and higher energy. A finger-strip plastic scintillator option has many advantages and is a lower cost alternative to keep the excellent HE performance at high luminosity. Measurements have been performed and this method has proved to be a good upgrade strategy.

The results of the investigation of the small-angle Raman-Nath scattering in the all-optically induced gratings of susceptibility inside the oxide glass mediums are presented and the theoretical basis of the observed phenomenon is suggested.

The results of the observation of process of the photo-induced frequency doubling of light in germanium-silicate patterns are presented. During the investigation a big anomalous growth of the light absorption has been detected in the region of the high induced electric field. The absorption blocks the process of the writing of the grating of the nonlinear second-order susceptibility and leads to the self-disappearance of the frequency doubling. Some properties of the observed phenomenon have been studied in experiments and the possible mechanisms of the dynamics of the observed processes are discussed.

The creation of photo-integrated volumetric nonlinear micro-structures in amorphous materials is discussed. The theoretical consideration of the formation of the nonlinear-optical spatial structures with small periodicity in a volumetric geometry of the creation of their profiles and the detailed analysis of properties of the inserted nonlinear polarizability has been presented. The obtained results of the experimental investigations show that, in comparison with the widely known simple method of the creation of nonlinear-optical structures by means of the plane-parallel laser beams, the considered case of the volumetric creation, by means of the crossed Gaussian beams in a volume of a sample, gives the important advantage connected with possibility of a wide variation of properties for the induced polarizability in volumetric media, allowing to create small-scale micro structures of the photo-integrated anisotropy with the different dimensions. As a result, the possibility of the creation of the spatially homogeneous photo-integrated volumetric modulation of anisotropy in oxide glass materials has been experimentally demonstrated. The studied photo-integrated nonlinear-optical spatially-periodic micro structures may be useful in future for the creation of the various photonic devices.

The results of the observation and investigation of the light-induced photorefractive effect, which arises by the action of the powerful two-component laser radiation on volumetric isotropic medium, are discussed. It is shown, that the lightinduced photorefractive grating can be created by powerful light in some isotropic silicate glass materials in which the sufficiently effective diffraction of radiation is observed by that. The theoretical calculations and experimental results of the investigation of the diffraction of radiation on the light-induced photorefractive gratings in volumetric glass mediums are presented and the observed characteristic peculiarities are analyzed.

The three-wave conversions (such as the nonlinear generation of light pulses of second harmonic frequency and parametric amplification of light signals), photo-induced in all-optically polled glasses materials, have been investigated. Theoretical considerations of the investigated phenomena show the interesting peculiarities of the process of three-wave conversions in photo-integrated volumetric micro-structures of nonlinear polarizability with the existence of a regime of synchronous two-beam transformations of light pulses. During the experimental investigation of the phenomena in the bulk oxide glasses the complicated kinetics of the formation of second-order polarizability gratings has been detected. Some properties of the phenomena have been studied and the possible mechanisms of the dynamics of processes are discussed.

The Phase I upgrade of the CMS Hadron Endcap Calorimeters consists of new photodetectors (Silicon Photomultipliers in place of Hybrid Photo-Diodes) and front-end electronics. The upgrade will eliminate the noise and the calibration drift of the Hybrid Photo-Diodes and enable the mitigation of the radiation damage of the scintillators and the wavelength shifting fibers with a larger spectral acceptance of the Silicon Photomultipliers. The upgrade also includes increased longitudinal segmentation of the calorimeter readout, which allows pile-up mitigation and recalibration due to depth-dependent radiation damage. As a realistic operational test, the responses of the Hadron Endcap Calorimeter wedges were calibrated with a 60Co radioactive source with upgrade electronics. The test successfully established the procedure for future source calibrations of the Hadron Endcap Calorimeters. Here we describe the instrumentation details and the operational experiences related to the sourcing test.

The three-wave conversions (such as the nonlinear generation of light pulses of second harmonic frequency and parametric amplification of light signals), photo-induced in all-optically polled glasses materials, have been investigated. Theoretical considerations of the investigated phenomena show the interesting peculiarities of the process of three-wave conversions in photo-integrated volumetric micro-structures of nonlinear polarizability with the existence of a regime of synchronous two-beam transformations of light pulses. During the experimental investigation of the phenomena in the bulk oxide glasses the complicated kinetics of the formation of second-order polarizability gratings has been detected. Some properties of the phenomena have been studied and the possible mechanisms of the dynamics of processes are discussed.

A general view of the CAMAC proton synchrotron slow extraction (SE) beam parameter monitoring and control system on-line with an US1010 computer is given. CAMAC provides an interface between the computer and transducers, as well as between the remote controlled SE devices, by means of a universal branch driver developed and used at the High Energy Laboratory as a standard interface for large CAMAC installations. The system is used to measure some parameters of the accelerator, which deter mine the operating made of slow extraction, of a slow extraction system and of an ejected beam. The system includes a closed feedback loop for making corrections in order to stabilize the ejected beam and to optimize the operation of the slow extraction system.

Abstract A coding and reading data unit from any CAMAC hodoscopic recording system is described.

Nonlinear conversions of laser radiation frequency on the photo-integrated volumetric structures of the second-order susceptibility, created by all-optical poling, have been investigated in various glass mediums. The detailed analysis of the influence of a chemical compound was carried out, and as a result, the perspective multi-lead phosphate glasses with the concentration of the some percents of niobium oxide have been synthesized in which the greatest efficiency of the conversion of light is observed in conditions of long lifetime of the photo-integrated structures. The studied photointegrated structures may be useful in future for the creation of the various photonic devices for micro- and nanoelectronics.

The creation of new light elements for different microscopy tasks remains actual at present since there are the problems with obtaining of the micro- and nano-scale light sources for investigations of various small objects with high spatial resolution and also for coherent real-time control during the processes of the formations of the high-ordered molecular and atomic systems. In this paper the investigations of the frequency conversion with signal generation of the green light on the micro-scale lattices integrated in the volumetric isotropic mediums are presented. The possibilities for creating of the prolonged microlattices uniformly distributed in volumetric mediums are discussed. The properties of the growing anisotropy in some effective multi-component matrixes are considered and the potential influence of the different elements is compared.

The photoinduced periodic susceptibility formed in various isotropic media is promising in future for possible practical applications in different areas of laser physics and photonics, in particular, for creation of the small-scale converters of light signals. The basic tasks of the investigations are to receive the samples not only with high efficiencies of the radiations conversions inside the inserted periodical susceptibility, but also with a long lifetime and stability to various kinds of influences. In this work we present the results of the investigations of the external red-light action on photoinduced susceptibility. The decay of the susceptibility under the action of the various intensities of red-light illumination is observed and the optimal conditions for sufficiently longtime stability are discussed.

This paper reports on the cross-calibration of an Active Well Coincidence Counter for use in the Materials Protection, Control, and Accountability Graduate Program at the Moscow State Engineering Physics Institute (MEPhI). The cross-calibration procedure and its application to nuclear material types available at MEPhI for instructional purposes is described. Cross-calibration results at Los Alamos and initial applications at MEPhI are summarized. Based on the results so far, the authors conclude that the cross-calibration approach seems useful, with good prospects for potential applications at other Russian and US Dept. of Energy facilities.

Exposures of oxide glass to two coherent light beams with different frequencies (omega) and 2(omega) leads to the buildup of spacial index gratings in the glass. This gratings are instable and can be amplified when the glass is illuminated only radiation with the fundamental frequency. In this letter we are reporting about new instability. We observed amplification of the refractive-index when glass was illuminated only second harmonic radiation of the laser. The results of the experiment can be explained by a model of a coherent photovoltaic effect. Mechanisms of the limitation of instability are analyzed. It is assumed that the limitation of the instability is as a result of increasing of the second harmonic radiation absorption, when the refractive-index is intensified.

In the history of evolution of the Western Transbaikal mobile zone two accumulation cycles of radioactive elements in intrusives are outlined: the lower- paleozoic and the mesozoic. In each of the cycles occurs first an increase of U- and Th-content and of the Th/U-ratio in rocks of successive magmatic phases, and then a lowering of the whole content of radioactive elements and of the Th/U- ratio. In the last magmatic phases of both cycles in parallel with the saturation of the melt with volatile components noticeably increases the role of mobile uranium. A tendency to primary uranium and thorium accumulation in acid and alkaline magma differentiates is outlined. (auth)

A method for improving the discrimination of semiconductor thin-film gas sensors, which utilises the amplitude and phase of the photocurrent response to a modulated light source, is proposed. The photoconductivity of microcrystalline silicon films is examined before and after exposure to the vapour of an iodine solution in ethanol. Preliminary results are presented which suggest that the density and/or capture properties of localised states may be reversibly modified. For cadmium selenide however, a small but systematic temperature-dependent phase lead is observed in this material at low frequencies, even under vacuum-annealed conditions. This is in contrast to present theory, which predicts that for an arbitrary localised state distribution the photocurrent response must lag the applied excitation.

The silicate materials are perspective for different areas of laser physics and photonics. In this paper the comparison of the nonlinear conversion with the generation of the light harmonic in Al- and Ge-containing silicate materials is presented. The peculiarities of the processes of the light harmonic generation in dependence on the concentrations of the chemical components are discussed and the influences of the additional small inclusion of the elements of fifth group and the rare-earth elements are estimated.

Summary Following the discovery of the K18-Golf Rotliegend gas field with the K18-7x well, its consecutive appraisal with K18-8, as well as extensive illumination and full waveform imaging studies, it became apparent that an innovative approach was needed to significantly improve the seismic image. Due to the very complex overburden, only patchy illumination was achieved with conventional single narrow-azimuth towed streamer seismic. Therefore, a multiazimuth acquisition and co-processing with legacy 3D was pursued to significantly improve subsurface illumination at acceptable cost. Following the multi-azimuth co-processing through time and depth imaging, the interpretation posed challenges in terms of number of seismic volumes as well as relative image quality variations. After treating each acquisition as stochastically independent realisation of the earth, their relative and independent quality variations could be interpreted in terms of imaging and feature position uncertainty.

The phase-matched conditions for waves interactions, which are used in different optical elements and complex devices, are necessary practically as a rule for obtaining the sufficiently big energy efficiency and also for realization of a high angular selectivity of the interacting light signals. In this paper we present the analysis of the realization of the phasematched conditions for the light interacting of the different frequencies on the photo-induced susceptibility gratings, which can be created, as now it is known, in different isotropic materials (the glasses, polymers and hybrids). The interactions of the light radiations with various frequencies on the photo-induced susceptibility gratings with small periodicities are discussed and the potential possible bandwidth from the visible and near infra-red spectrums is analyzed.

The analysis of the summary investigation results of a nonlinear process of generation of the laser frequency harmonic on the second-order susceptibility gratings photo-integrated in different consisted glass materials are presented. The basic attention is concentrated on the results of study of the properties of the frequency harmonic generation in oxide materials with the variations of the concentrations of the lead-oxide, the some elements of the first-five groups and the rare-earth elements. The influence of the variations of the chemical components on the formation of the photo-integrated second-order susceptibility gratings in investigated samples and also on the process of the frequency harmonic generation is analyzed.

The study of an influence of the different chemical components on process of the nonlinear generation of light harmonics in various isotropic glasses, polymer and composite materials attracts an attention of scientists in connection with a possibility of future development of new high effective broadband optical elements for micro- and nano-optoelectronics. In this paper the effect of lead oxide concentration on the generation of light harmonics in different optical glass media is analyzed. The attention of investigation is focused on the detailed comparison of the results of study of the writing times, relaxation processes and the potential efficiencies of the nonlinear generation of light harmonic in various composite samples.

The light stimulated anomalous self-blocking of all-optical poling process is observed. During investigation the big selfdecrease of light intensity of the generated signals of photo-induced second-harmonic generation has been detected in the region of high values of the induced electric field. The appeared self-decrease of light intensity blocks the process of the writing of the grating of nonlinear second-order susceptibility and leads to the restriction of the maximum value of photo-induced second-harmonic generation. Some properties of the observed phenomenon have been studied and the possible mechanisms of the dynamics of processes are discussed.

GaInP microdisks contained InP/GaInP quantum dots having lateral size ∼150 nm and 1-5 μm−2 were investigated with help of microphotoluminescence technique. Experiments carried out in confocal, time-resolved and low-temperature modes. Comparison of results allowed to conclude that overlap of quantum dot emission area with whispering gallery mode antinode results in faster luminescence lifetime (Purcell effect). Whispering gallery mode lasing was detected. Obtained threshold power values were following 6 µW (Q=4500, T=8.5 K) and 0.4 µW (Q=7400, T=80 K).

Novel experimental results of anomalous luminescence and optical bleaching of large molecules concentrated in solution, influenced by intense laser pumping, are presented. The theory based on resonance 4-photon interaction with two zero vacuum oscillation is developed.

Abstract The large growth of the absorption of radiation with doubled frequency in a region of high values for the induced electric fields has been detected during the investigation of an optical poling process in germaniumsilicate glass. The absorption suppresses the writing of the second-order susceptibility grating and leads to restriction of the maximum efficiency of the photoinduced second-harmonic generation in the glass.

By all-optical poling of a medium the long-lived space-periodic electrostatic field arises inside the sample and, as a result of such induction, an isotropic medium gains the properties of an inhomogeneous optical single-axis crystal. The space distribution and the maximum value of the resulting induced electrostatic field in the present of the current mechanism of all-optical poling are substantially depending on the geometry of poling process in medium during the interaction of intersecting laser beams. All-optical poling process is theoretically studied at different conditions of two-beam interaction in an conductive isotropic media and the spatial distributions of the resulting induced electric fields are analyzed. The efficiencies and the features of the typical geometrical schemes of all-optical poling are discussed.

The second harmonic generation, which appears upon optical poling of a bulk glass have been investigated theoretically and experimentally. The existence of two-beam generation pattern has been shown and peculiarities of the kinetics of process have been studied in oxide glass.

The three-wave interactions (second harmonic generation and parametric amplification of light), photoinduced during all optical poling of glass, have been investigated. Theoretical consideration of the phenomena in a bulk glass shows the interesting peculiarities of the process of three-wave interactions which lead to the two-beam conversion of light in optically transformed mediums. During the experimental investigation of the phenomena in the bulk oxide glass the complicated kinetics of the formation of second-order susceptibility grating has been detected. Some properties of the phenomena have been studied and the possible mechanisms of the dynamics of processes are discussed.

The transmittance and luminescence of concentrated solutions of rhodamine 101 excited by laser pulses in the Stokes and anti-Stoke regions of the spectrum have been experimentally investigated. It is shown that a substantial role in forming the luminescence is played at large pump energies by collective photoinduced luminescence, which competes with induced emission. Estimates are made of the heating and cooling of solutions. © 2005 Optical Society of America

The article presents the results of a pilot clinical study of a new method of photodynamic therapy in patients with liver cirrhosis, indicating an improvement in this organ functional state and reduction of connective tissue in it.