2007 IEEE 34th International Conference on Plasma Science (ICOPS)最新文献

{"title":"25 - 100-keV X-Ray Diagnostics for the 200-TW Trident Laser","authors":"J. Cobble, J. Workman","doi":"10.1109/PPPS.2007.4345543","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345543","url":null,"abstract":"The sub-ps Trident laser is upgraded to deliver >100 J on target. We are prepared to measure conversion efficiencies of 200-TW laser light to K-shell emission. X-ray diagnostics include a simple, inexpensive Laue X-ray spectrograph and a set of Ross filter pairs. The sensitivity of Si p-i-n diodes is adequate to record X-ray emission up to 100 keV. With carefully matched Ross filter pairs, the diodes permit estimation of the signal between the filter edges of two channels through subtraction of signals. Estimates suggest that the signal-to-noise ratio of the K-shell signal to X-ray continuum and leakage from filter mismatch is adequate to determine the conversion efficiency. These instruments will be employed to optimize the efficiency of X-ray backlighters in this energy range.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123718038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aspects of Transport in Laser Produced Plasmas","authors":"W. Manheimer, D. Colombant, V. Goncharov","doi":"10.1109/PPPS.2007.4346086","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4346086","url":null,"abstract":"Summary form only given. We have been examining two aspects of transport in laser fusion plasmas. Both have to do with the fact that the mean free path is not necessarily short compared to the gradient scale length. Electrons on the tail of the distribution function can penetrate beyond the gradient scale length. We have devised a Krook model which can be easily incorporated into a conventional fluid simulation. It is more than a flux limit, but less than a full kinetic simulation. In the small mean free path limit, it gives classical theory, and follows departures for classical theorv as the plasma heats up. Results are presented showing the effect of this non local heating.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115561567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-Fast Acceleration of Macroscopic Objects in Coaxial Electromagnetic Launcher","authors":"R. M. Garipov, V. Kataev, V. Klimashov, P. Korolev, A. S. Pikar’, A. S. Russkov, V. Selemir, Yu. M. Shibitov","doi":"10.1109/PPPS.2007.4346295","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4346295","url":null,"abstract":"Summary form only given. In the paper we present experimental results on launcher of steel projectiles of 15 length caliber in a coaxial electromagnetic launcher. An ultra-fast acceleration of lengthy projectiles in ordinary rail electromagnetic accelerators is associated with definite technical troubles. Currents with a linear density of 108 A/m should be passed on the rails at acceleration rate of 10 m/s2. This leads to a surface explosion. Besides, a magnetic pressure effects not only the projectile, but also the whole design of the launcher destroying the current carrying bars.In the considered launcher the current linear density does not exceed 2.4-107 A/m. Due to axial symmetry of the construction deformation, a magnetic field pressure is not high. However, a linear inductance of a coaxial is smaller, and high currents are necessary for acceleration. In our experiments powering of the launcher with a bore length of 30 cm was provided from a high-voltage capacitor bank of 900-1350 muF capacity at a voltage of 25 kV. Matching of the low impedance launcher with the high-voltage battery was carried out with step-down cable transformers with transformation coefficients of 28 and 15 depending on the experiment edition. Acceleration of the projectiles of square section of 4x4 mm, length of 60 mm made of stainless steel 12X18H10T of 7.5 g was studied. At full current of the launcher of 1.5 MA and 2.4 MA the projectile velocity was 0.7 km/s and 1.3 km/s, acceleration rate was 5-106 m/s\" and 10' m/s2, correspondingly.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116344511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Processing of Films and Fabrics with the MOD-VIII Roll-to-Roll One Atmosphere Uniform Glow Discharge Plasma (OAUGDP®) Reactor","authors":"Zhe Chen, Qingquan Li, S. Nourgostar, J. Reece Roth","doi":"10.1109/PPPS.2007.4345622","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345622","url":null,"abstract":"Summary form only given. Industrial atmospheric pressure plasma treatment has unique advantages over vacuum plasma technology for material surface energy enhancement, surface cleaning and decontamination, sterilization, surface etching and related tasks. The MOD-VIII plasma reactor studied in this paper consists of a fabric feed system, a gas feed system, a water cooling system, and a OAUGDPreg plasma reactor. We have shown that a roll of polymer film or fabric can be run through the reactor while being exposed to the plasma generated between a flat and a cylindrical drum electrode. The fabric is cooled by contact with the stainless steel water-cooled rotating drum electrode; the fabric exposure time is precisely controlled by a belted drive system driven by a variable-speed motor; and the fabric tension is controlled by a second variable-speed motor on the take-up roll. The fabric surface charge is drained at two grounded locations after treatment. We have obtained a uniform OAUGDPreg plasma with no filaments or pin holing in the exposed fabric. Subsequent measurement of the surface energy by the sessile water drop and related tests show that the surface energy after exposure is raised to levels well above those required for industrial use. Data on the uniformity of the surface energy in the cross and machine direction will be presented. This flexible MOD-VIII plasma reactor can be used for a wide range of material surface treatment purposes.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122341260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma Diagnostics using Cavity Ringdown Spectroscopy Combined with Optical Emission Spectroscopy","authors":"C. Wang, Y. Duan, T. Dibble","doi":"10.1109/PPPS.2007.4345754","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345754","url":null,"abstract":"Cavity ringdown spectroscopy (CRDS) is a sensitive absorption spectral technique and capable of measuring absolution concentration of species in a variety of environments. In recent years, CRDS has been increasingly applied for plasma diagnostics. Through measurements of high resolution spectral linewidths of selected species, plasma gas kinetic temperature and electron density profiles can be determined from the lineshape broaden components (Lorentzian and Doppler components). Determination of the distribution of particular chemical species, such as transient radicals, can help understand plasma associated chemistry. Plasma thermo-equilibrium status can be evaluated by simultaneously analyzing ringdown-based absorption and optical emission spectra of a diagnostic agent in the plasma. This talk presents three powerful approaches for plasma diagnostics: analysis of linewidth broadening of selected optical transitions, determination of density distribution profile of chemical species, and simultaneous measurements of absorption and emission spectra. Additionally, the advantages and challenging issues of CRDS for plasma diagnostics will be discussed.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"205 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122772835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconnection Effects in z-pinch Wire Arrays from 2-D Hall-MHD Simulations","authors":"C. Seyler, D. Hammer","doi":"10.1109/PPPS.2007.4345705","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345705","url":null,"abstract":"Summary form given only. Understanding the initial stages of plasma formation in cylindrical wire-array Z-pinches is a complicated process that probably cannot be fully understood using standard MHD modeling and computer simulation. Results from 2D Hall magneto-hydrodynamic simulations of wire array Z-pinches, using a code specifically developed for this purpose, are presented. In the coronal plasma near the point where the magnetic field reverses due to cancellation by the global magnetic field of the local field from an individual wire, reconnection is found to occur and have considerable effect. The reconnection jets directed towards the central axis significantly contribute to the energetics of the plasma streaming onto the precursor. Direct conversion of magnetic field energy into directed kinetic energy as well as thermal energy due to reconnection is comparable to that resulting from the usual global JxB acceleration of plasma. Results from both MHD and Hall-MHD simulations are compared.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129552194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Sheet Beam Slow Wave Interaction Structures","authors":"S. Cooke, B. Levush, T. Antonsen, R. Shtokhamer","doi":"10.1109/PPPS.2007.4346182","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4346182","url":null,"abstract":"Summary form only given. A potential problem inherent in the sheet beam geometry is the proximity of competing high-order modes in the same frequency band, with longitudinal and/or transverse fields. Each can lead to instability, with the potential for beam disruption. We present results of our analysis to determine the mode structures and impedance in each case, for realistic device dimensions. We also present a scheme to implement efficient input/output coupling for this structure.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128713433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel Closing Switches on the Base of Fast Ionization Fronts in Semiconductors","authors":"I. Grekhov, S. Korotkov, P. Rodin","doi":"10.1109/PPPS.2007.4345738","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345738","url":null,"abstract":"Summary form only given. Subnanosecond switching of Si diode under fast (> 1 kV/ns) overvoltage in reverse direction was observed for the first time in 1979. Later it was shown that very efficient closing switches can be designed on the basis of this phenomenon in the p+npn+ dynistor structures. These devices - called fast ionization dynistors (FIDs) - have become the main elements of high power pulse generators of nano and subnanosecond range. Physical basis of fast switching of FIDs is the passage of fast ionization front in the wide n-base of the p+npn+ dinistor structure. The impact ionization in the neutral part of the n-base is considered as a source of free carriers that initiate this passage. Recently we found that tunnel emission from deep (~ 0.5 eV) electron traps is the possible source of free carriers for ionization front triggering. These traps are produced in the n-base during the manufacturing process. Neutral part of the n-base is not necessary in this case. Hence the total thickness of the base layer can be considerably reduced. As a result the residual voltage just after switching (0.1-0.5 ns) as well as during high current conducting mode (10-100 ns) decreases several times. Devices with such triggermg mechanism are called deep level dynistors (DLDs). Several types of DLD-based generators will be discussed in this presentation to illustrate these devices application areas: (i) nitrogen laser pumping (15 kV, 1 kA, 2 ns, 100 Hz), high voltage pulse generator (40 kV, 2kA, 3 ns), high power pulse generator (25 kV, 5 kA, 300 ns) for triggering the RSD-based switch (25 kV, 200 kA, 500 microsec) used for high power solid-state laser pumping. Computer simulations show that overvoltage with 10 kV/ns raise rate applied to the diode without any traps gives a possibility to achieve the electric field strength as high as 106 V/cm at the pn junction. Then free electrons are generated via band-to-band tunneling in the region of highest electric field and initiate passage of superfast ionization front with velocity ~5 108 cm/s. Typical turn-on time in this case can be as short as 20 ps.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129047021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dusty Plasma Bubble - Dust Acoustic Wave Interaction","authors":"Hong-Yu Chu, Chen-Ting Liao, L. I","doi":"10.1109/PPPS.2007.4346229","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4346229","url":null,"abstract":"Summary form only given. We experimentally investigate the interaction between dusty plasma bubble (DPB) and self-organized dust acoustic wave (DAW) in a low pressure dusty plasma liquid suspended in a weakly ionized low pressure rf discharge through video microscopy. The dusty plasma bubble (DPB) can be formed as dust particles are expelled by pulsed laser ablation on one of the particle in a dusty plasma liquid cluster suspended in weakly ionized low pressure discharge. DPB with dust depletion maintains its spherical shape and travels downward faster than the downward traveling DAW self-organized in the lower part of the liquid. The collision between DPB and DAW generates a wake with large density fluctuations trailing DPB. The detailed dust dynamics are discussed.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129250479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the Ionization and Recombination Processes in Low-Density Plasma Based on the Statistical Model of Atom","authors":"S. Garanin, E. M. Palagina","doi":"10.1109/PPPS.2007.4345445","DOIUrl":"https://doi.org/10.1109/PPPS.2007.4345445","url":null,"abstract":"Summary form only given. The issue of plasma irradiation on impurities is very important for the MAGO/MTF approach as it provides considerable contribution to plasma cooling. The density of the MACK VMTF plasma is rather low, therefore the radiation processes can be considered in the coronal limit. If we are interested in radiation on heavy impurities with big number of electrons, the statistical approach can be used for the plasma-electron interaction kinetics description (and, accordingly, the radiation occurring at such interaction). The discrete transitions and lines in this approach are taken into account statistically and on the average. In this paper, the ionization and recombination processes proceeding in plasma in free electrons-ions collisions are considered basing on the atom statistical model. The ionization and recombination processes can be presented in this approximation as the process of binary collisions of electrons in the atomic electron gas. The expression for the ionization rate depending on the ionization potential / and temperature T is obtained. This formula shows that at 1>> T the ionization rate is proportional to exp(-I/T). In the proposed approach, the recombination rate is calculated for an ion with high nuclear charge Z, and at arbitrary Z the recombination rate is estimated. The obtained values of the ionization and recombination rates are in reasonable agreement with available experimental data. The considered model explains low coronal model values of I/T , as compared with the Saha equation, and the reduction of these values with the growth of Z. The values I/T and the mean ion charge obtained from the balance equation for multi-electron ions using one fitting coefficient agree with the tabular data obtained in the multi-level coronal model. The obtained results can be applied not only to the MAGO/MTF plasma but also to the systems with magnetic plasma confinement and to low densitv cosmic plasma.","PeriodicalId":446230,"journal":{"name":"2007 IEEE 34th International Conference on Plasma Science (ICOPS)","volume":"05 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130521318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}