N.. Basov , G.. Hager , A.. Ionin , A.. Kotkov , A.. Kurnosov , J.. McCord , A.. Napartovich , L.. Seleznev , N.. Turkin
№ 15 Multiline and single line pulsed first-overtone co laser frequency tuned within spectral range of 2.5-4.2мкм
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Output characteristics of a pulsed e-beam controlled discharge laser operating on the first-overtone (FO) transitions (AV=2) of CO molecule have been studied both experimentally and theoretically. Various sets of dielectric mirrors with high reflectivity in the range of the overtone sncctnim have been used for the laser resonator. Multiwaygiensith iasins has been obtained in the wide spectral range of 2.5 — 4.1 urn on vibrational transitions from 6?И up to 37??35. Amaximum output efficiency of 11%, the highest ever published for а БО CO laser, has been experimentally obtained for the broad band muitiiine FO CO iaser. Maximum specific output energy (SOE) is 50 J/1 Arnagat. Output efficiency of the laser operating on a few vibrational bands within the relatively narrow spectral range 2.5-2.7 urn comes up to 5% at entirely suppressed fundamental band (ДУ=1) lasing. FO CO lasing was observed within an initial gas temperature interval of 100-220 K. Spectral characteristics of the overtone iaser operating on a selected set of vibrational bands have been analyzed theoretically. Theoretical calculations based on the experimental data predict that multiline FO CO laser efficiency can be increased up to 20%. Experiments with a pulsed FO CO laser using a diffraction grating as a frequency selective element demonstrated the feasibility of developing a frequency tunable smgie line pulsed FO CO laser. Tunable FO CO lasing on wavelengths from 2.74 up to 4.15 urn corresponding to vibrational transitions from 13?>11 up to 38->36 was obtained. The maximum SOE came up to 2.8 J/1 Amagat, with single line output efficiency being up to 0.6%.
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V.N. Ochkin , S.N. Tskhai , E.F. Shishkanov , F.J. Blok , W.J. Witteman
№ 40 Life time tests of the RF pumped atomic xenon lasers
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N.V. Markova
№ 42 On the neutron quantum liquid in pulsars
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The neutron stars investigations’ results taking a place at the today arc presented in the given work. The two alternative scenarioos of the superfluid neutron liquid behaviour are described: the neutron Rose — liquid and the neutron Fermi — liquid. For trie present moment the question about which of these scenarioos take a place in fact is remained open. It is not excepted that both versions are realized. The general formulation of relativistic many — particle theory of the neutron matter of high density with taking into account of the gravitational field is given in the article. So, the possibility to take into account the gravitational field influence on the state equation of the neutron matter appeares. The tensor of energy — moment which is the source of metric tensor curvature in the Einstein equations can serve the equivalent replacement of the state equation. There is considered the cold condensed neutron matter so that the temperature is supposed effective — zero. It is clear that the deflexions from the general relativity, if any, must be displaied for the neutron stars in first turn.
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B.. Stern , Ya.. Tikhomirova , D.. Kompaneets , M.. Stepanov , A.. Berezhnoy , R.. Svensson
№ 43 A search for Non-Triggered gamma ray bursts in the BATSE continuons records:Preliminary results
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We present preliminary results of an off-line search for non-triggered gamma-ray bursts (GRBs) in the BATSE daily records (obtained with 1024 ms time resolution) covering about 7 years of observations. We found 1353 non-triggered and 1581 triggered GRBs. The scan was done with artificial test bursts added to the data which allowed us to measure the efficiency of the search and to extend the log N ? logP distribution down to P ~ 0.1 ph cm~2 s_1. Previous indications of a turnover of the log N ? log P distribution at small P are not confirmed. The distribution cannot be fitted with a standard candle model with a non-evolving GRB source population. The most probable interpretation of the shape of the log/V ? logP distribution is that the intrinsic luminosity function of GRBs is wide.
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P.S. Baranov , A.S. Belousov , A.M. Fomenko , A.I. Lebedev , I.A. Lebedev , E.I. Malinovsky , S.V. Rusakov , Yu.V. Soloviev
№ 53 Radiation hardness of heavy monocrystals KRS, NBW, OWO
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The comparative study of radiation hardness of KRS, NBW and PWO crystals used in the calorimetry of high energy particles is performed. Their spectral transparency is measured before and after irradiation by a big doses (к lOOMrad) frornCo60/—source. The scintillating crystal PWO did not lose practicaiy its transparency whereas among cherenkov radiators KRS and NBW the last one had better radiation resistance. The influence of irradiation of KRS and NBW crystals by high energy (up to 25 GeV) photons and electrons on their transparency was also investigated at doses 10-100 Mrad.
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Yu.A. Merkul
№ 57 Deuterium-tritium exchange in polystyrene microsheres
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More than 40 years researches with organic substances marked by a radioactive isotope of hydrogen — tritium are conducted. The Wiizbach method or its modification is applied to derive substances containing tritium. The method consists of the following. The substance is withstood in an atmosphere of gaseous tritium by several days or weeks. For this time under the influence of an exposure by tritium p»-particles in substance the exchange reactions between atoms of hydrogen in substance and gaseous tritium flow past. Surplus of gas is then removed. Compound marked by tritium is cleaned using crystallization, distillation, sublimation and other techniques. Wiizbach method was supplemented by various ways of acceleration of exchange reactions by using of various radiation (electrical discharge in gas, ultra?violet and x-ray radiation, microwave excitation and so on.). Last years the attempts were undertaken to replace a significant part of a deuterium with tritium in shells — laser targets from deuterited polystyrene, using Wiizbach method or its modification connected to an additional exposure by ultra?violet light. But it was not possible to reach 50 % of substitution, that is connected with degradation of polymer under the effect of radiation of high energy in comparison with an energy of carbon — carbon or carbon — hydrogen connections. In the given work the attempt to describe mathematically the process of exchanging of hydrogen isotopes, taking account of connections degradation is undertaken. The results of calculations allow us to explain the available experimental data and to give recommendations for the further work in that field. The polymer degradation at p-particles irradiation from tritium limit a possibility to use polymer shells — laser targets in experiments with large time of expectation.
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A.. Voronin , G.V. Margagliotti , G.. Pauli , L.. Santi , S.. Tessaro , E.. Zavattini
№ 59 Antiproton transfer from antiprotonic He to noble gas contaminants
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The state dependent quenching mechanism of metastable antiprotonic Hejitom by contaminants is suggested to explain existing experimental data. The effect о antiproton transfer from the antiprotonic He to noble gas contaminants is showi to play a significant role. Preliminary estimations have been done in the frame work of the coupled channels model. The obtained results support the idea о strong dependence of quenching cross-sections on the antiprotonic states quan turn numbers and enable to explain qualitatively existing discrepancies betweei experimental results, obtained for different contaminant densities. New observabl effects axe predicted.
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N.G. Borisenko , A.I. Gromov , S.Yu. Guskov , V.M. Dorogotovtsev , Yu.A. Merkul»ev , Ya.E. Markushkin , N.A. Chirin , A.K. Shikov , V.F. Petrunin
№ 62 Research of target fabrication possibility for new direct smoothing laser irradiation
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We discuss new fabrication methods for the production of ICF capsules with ablators composed of low density beryllium and beryllium hydride doped with high Z elements. In these targets the high Z doped, low-density beryllium or beryllium hydride ablator foams, which are near the critical plasma density, absorbs the direct drive laser energy and converts it to X-rays. The fabrication technology [1] allows us to radially control the dopant concentration, and thus realize a new target design for direct drive implosions with a controllable level of conversion to x-ray radiation [2]. In comparison with direct-indirect target [3] new target allow to reach 90% level of conversion to x-ray (in [3] 12%-24%). This level considerably weakly depends from optical thickness of layer and from laser pulse duration up to 30 nsec at Be(Au) density in the range 0.005- 0.05 g/cm3 (Au concentration in Be is 2%-5% atomic). The target with low concentration of the gold can be used in the experiments on direct implosion or direct-indirect .compression (the direct compression with partial conversion of laser light into X-ray which is need to smooth the nonuniformity of laser beam energy deposition). In the case of direct implosion the target must contain more higher concentration of doped Au in inner Be layer to protect compressible part of target from x-ray preheating.
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S.. Potashov , V.. Kozlov , V.. KORBEL , l.. JOENSSON , E.. DEVITSTN , A.. BLOERCLUND , A.. Terkulov
№ 63 THE BEAM TEST OF A PbWO4 CRYSAL CALORIMETER AT DESY
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The performance of a prototype calorimeter based on four PbWO^ crystals doped with lanthanium has been investigated in the energy range of 1 to 6 GeV. The measurements were carried out at a DESY electron test beam. Results concerning the energy resolution and the spatial characteristics of shower development in the prototype are reported.
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R.M. Graves , A.A. Ionin , Yu.M. Klimachev , A.P. Mukhamedgalieva , D.G. O’Braien , D.V. Sinitsyn , Yu.V. Terekhov , V.D. Zvorykin
№ 67 Interaction of pulsed CO and CO2 laser radiation with rokcstypical for the oil fields
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Experiments on laser — rock — fluid interaction have been carried out by using pulsed CO and C02 lasers which irradiated rocks typical for oil field: sandstone, limestone, shale and granite. Energy fluence and laser intensity on rock surface were up to l.OkJ/cm» and 10 W/’cm2, respectively. The dependencies of specific energy consumption (i.e. energy per volume needed for rock excavation) on energy fluence, the number of pulses, saturated ?lUici, iocK material ami irradiation conditions have uccn obtained for various rock sarnpics. The dependencies of momentum transferred to the rock on energy fluence for dry rocks and r/v*Wc with сигнал*? cptiire*pn mpacnr^H Mioh-cnppH photography procedure has been used for analysing laser plasma plume formation on a rock surface. Infrared spectra of reflectivity and absorption of rocks before and after irradiation have been measured. Microhardness before and after laser irradiation of rock surface has been analysed.
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M.A. Chernyakova , A.F. Illarionov
№ 68 Non-pulsed radio emission from the binary system PSR B2159-63
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PSR B1259-63 is the only known binary system with a radio pulsar from which the non-pulsed radio and X-ray emission was detected. The companion star in this system is a Be star SS 2883. A rapidly rotating radio pulsar is expected to produce a wind of electromagnetic emission and relativistic particles. Be stars are known to produce highly asymmetric mass loss. Due to the interaction of the pulsar wind and the Be star wind the system of two shocks between the pulsar and the Be star forms. In this paper we show that the observed non-pulsed radio emission from the system is a result of the synchrotron emission of the relativistic particles in the outflow beyond the shock wave.
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A.A. Ionin , Yu.M. Klimachev , Yu.B. Konev , A.A. Kotkov , A.K. Kurnosov , A.P. Napartovich , L.V. Seleznev , D.V. Sinitsyn , Yu.V. Terekhov
№ 70 Experimental and theoretical study of multiquantum vibrational kinetics in active medium of co laser
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An experimental methodology and theoretical model for studies of vibrational exchange between highly excited CO molecules are described. The history of researches in this field is reviewed showing evolution of theoretical understanding. A detailed description of the experimental methodology allowing for studies of effects of relaxation of the vibrational distribution after a sudden disturbance is given. The disturbance of the vibrational distribution is produced by Q-switched short pulse of single line radiation in fundamental band. The relaxation is studied by measuring laser pulse energy of the second pulse initiated by resonator Q-switching produced with variable time delay relative to the first pulse. In contrast to traditionally used kinetic theory based on approximation of single-quantum vibrational exchange, more realistic model is developed accounting for multi-quantum exchange processes. A set of kinetic constants accepted in the model for different gas temperatures, vibrational level numbers and number of exchanged vibrational quanta from 1 to 4 is presented. The model formulated is employed for description of experimental measurements. Results of comparison between experimental data, the developed theory and traditional theory clearly demonstrate that the traditional theory is inapplicable for accurate predictions of results for vibrational levels higher than the 14-th. Good agreement between experimental data and results of the advanced theory confirms for the first time that kinetic constants of multi-quantum exchange calculated in work of Billing et al allow adequate description of evolution of vibrational distribution on high-lying levels. Besides, in the paper the results of comparison of experimental and theoretical data on characteristics of pulsed single-line overtone CO laser are presented. The conclusion is drawn about satisfactory agreement between the advanced theory and the experiments.
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