2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)最新文献

{"title":"Estimates of Saturn Radiation Output Scaling versus Machine Design Parameters","authors":"K. Struve, T. Grabowski, N. Joseph, B. Oliver, M. Savage, B. Ulmen, P. Vandevender","doi":"10.1109/MEGAGAUSS.2018.8722658","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722658","url":null,"abstract":"Saturn is a short-pulse (~ 40 ns FWHM) x-ray generator capable of delivering up 10 MA into a bremsstrahlung diode to yield up 5 × 10^12 rad/s (Si) per shot at an energy of 1 to 2 MeV. With the machine now over 30 years old it is necessary to rebuild and replace many components, upgrade controls and diagnostics, design for more reliability and reproducibility, and, as possible upgrade the accelerator to produce more current at a low voltage (~ 1 MV or lower). Thus it has been necessary to reevaluate machine design parameters. The machine is modeled as a simple LR circuit driven with an equivalent a sine-squared drive waveform as peak voltage, drive impedance, and vacuum inductance are varied. Each variation has implications for vacuum insulator voltage, diode voltage, diode impedance, and radiation output. For purposes of this study, radiation is scaled as the diode current times the diode voltage raised to the 2.7 power. Results of parameter scans are presented and used to develop a design that optimizes radiation output. Results indicate that to maintain the existing short pulse length of the machine but to increase output it is most beneficial to operate at an even higher impedance than originally designed. Also discussed are critical improvements that need to be made.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"322 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123311874","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":"Megagauss-field effect on the metal-insulator transition in $mathrm{V}_{1-x}mathrm{W}_{x}mathrm{O}_{2} (x = 0.06)$","authors":"Y. Matsuda, D. Nakamura, A. Ikeda, S. Takeyama, Y. Muraoka, Yuki Suga","doi":"10.1109/MEGAGAUSS.2018.8722672","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722672","url":null,"abstract":"Effects of ultrahigh magnetic fields on the electronic state of $mathrm{V_{1-x} W_{x}O_{2} (x=0.06)}$ are investigated. Optical transmission increases with decreasing temperature due to the transformation from the high-temperature metallic state to the low-temperature insulating state. We have made optical transmission measurements with 2 μm wavelength laser light, and found that the low-temperature insulating state is suppressed by ultrahigh magnetic fields exceeding around 100 T.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124761085","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":"1000 T project of the electro-magnetic flux compression at Kashiwa, UTokyo","authors":"S. Takeyama, D. Nakamura, A. Ikeda, H. Sawabe, Yasuhiro H Matsuda","doi":"10.1109/MEGAGAUSS.2018.8722645","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722645","url":null,"abstract":"The megagauss laboratory, ISSP, UTokyo has a long history of generation of megagauss fields, especially using the electro-magnetic flux compression, originated from the original work in 1970s. We have initiated a new project of 1000 T since 2011, and since then, we have been devoting ourselves to installation of the system and the technical improvements. Condenser bank units with 20 kV, 2 MJ for seed feed coils, and two set of main condenser bank units, 5MJ and 2 MJ each with 50 kV charging capability. The system comprising of those condenser modules has been installed, and operation tuning has been completed. The giant collector plates, and load coil clamping units are installed in anti-explosion chambers. Design of all those instruments was optimized to substantial improvement of the electro-magnetic field energy conversion efficiency. Our recent results of record magnetic field 1200 T obtained from our new megagauss generating systems is presented.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129871687","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":"25th Anniversary of the Joint US-Russian Disk EMG Experiment","authors":"A. Buyko, R. Reinovsky, S. Garanin, I. Lindemuth","doi":"10.1109/MEGAGAUSS.2018.8722651","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722651","url":null,"abstract":"Twenty-five years ago, on September 22, 1993, an event, unprecedented in the nuclear age, took place at Arzamas-16, Russia, as the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and the Los Alamos National Laboratory (LANL), the two institutes that designed the first nuclear weapons of their respective nations, combined capabilities to conduct a joint scientific experiment. The experiment used a VNIIEF disk explosive magnetic flux compression generator (EMG) with an electrically exploded foil opening switch (FOS) to transfer multi-megajoule pulse of electric energy on a microsecond timescale to a magnetic implosion assembly. Despite a breakdown in the transmission line, the experiment delivered a load current of 20 MA, then-unattainable in stationary laboratory-scale experiments, and drove an electrically exploded liner to a velocity of 25 km/s. The experiment demonstrated the applications of the EMG-based pulsed power system to high energy density research, and resulted in the subsequent expansion through the 1990s and into the 2000s of joint VNIIEF/LANL EMG-enabled work on imploded liners and their applications. The success of the joint efforts led to new projects in plasma physics and fusion research, materials science, and driver technology development; and set the stage for additional programs in material control and accountability and several other high level international agreements on cooperation. The collaboration between VNIIEF and LANL demonstrated that joint efforts can deliver results not heretofore attainable through the efforts of any one institution. The results of this work constitute important milestones in physics and engineering development and are widely used today. These results include but are not limited to the following: •Magnetized hot plasma studies as applied to fusion ignition in MAGO-MTF systems; •Record-setting liner energy in the HEL-1 experiment (the 25-MJ record of this experiment has not been beaten yet) making the liner suitable for plasma compression in the MAGO-MTF system; •Use of disk EMGs with FOS to drive condensed-matter liners and to study materials properties (ALT-1, 2, RHSR-1, 2 experiments).","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125678029","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":"Contactless ultra-high frequency AC-conductivity measurement applicable to destructive magnets above 100 T","authors":"D. Nakamura, A. Ikeda, Y. Matsuda, S. Takeyama","doi":"10.1109/MEGAGAUSS.2018.8722657","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722657","url":null,"abstract":"The contactless high-frequency electrical conductivity measurement using a “self-resonant” probe coil was performed under the ultra-high magnetic fields generated by the destructive magnets, and applied to measure the upper critical field of the cuprate superconductor La1.84Sr0.16CuO4, and also applied to observe a semiconductor-metal transition of the narrow gap semiconductor FeSi.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131589002","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":"Study on the Electromagnetic Flux Compression using 3D Simulation","authors":"K. Takekoshi","doi":"10.1109/megagauss.2018.8722655","DOIUrl":"https://doi.org/10.1109/megagauss.2018.8722655","url":null,"abstract":"Computer Simulation of the Electromagnetic Flux Compression has been carried out using three-dimensional finite element method. It is found that the simulation successfully predicts inner diameter of the liner coil depending on the magnetic field. It is also found that a characteristic deformation inside the liner coil is predicted and is considered to be a key factor for the generation of ultra-high magnetic field.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132527494","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":"Review of Controlled Fusion Power at Megagauss Field Levels","authors":"P. Turchi","doi":"10.1109/MEGAGAUSS.2018.8722684","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722684","url":null,"abstract":"For well over half a century, there has been interest in using megagauss magnetic fields for thermonuclear fusion. Efforts at IAE Kurchatov under E.P. Velikhov for controlled fusion using “theta-pinch with liner” inspired similar work (c. 1970–79) at the Naval Research Laboratory in the Linus program. Apart from the many scientific problems of electrical conductors at megagauss field levels, and the several instabilities that could plague the dynamics of liner implosions, there are issues of converting single-shot technologies into economical fusion power reactors. Linus ended in 1980 because it lacked a proper plasma target for liner compression, but interest has revived recently driven by the recognition that a substantial minimum in cost and size exists in a regime between the mainline fusion approaches of magnetic-confinement (e.g., ITER) and inertial confinement (e.g., NIF). Attainment of this low-cost minimum, which occurs at about a megagauss, requires successfully overcoming three main challenges: 1) combination of the flux compression process with an appropriate plasma target that can be adiabatically compressed to fusion temperatures and densities; 2) repetitive operation of this implosion in an economically useful manner; and 3) protection of the reactor, especially electrical components, from the very high output of high-energy neutrons. Issues of the fusion power reactor and experimental development are discussed.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"451 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133270661","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":"Recalling Max Fowler. Devoted to the 100-th Anniversary of Clarence M. (Max) Fowler","authors":"G. Shvetsov, J. Goforth","doi":"10.1109/MEGAGAUSS.2018.8722683","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722683","url":null,"abstract":"During the “Megagauss XV” Conference in Portugal, the International Steering Committee voted to ask professor Shojiro Takeyama and the Institute for Solid State Physics, the University of Tokyo host the next “Megagauss-XVI” Conference in Japan and to dedicate it to the 100 birthday of Dr. Clarence M. Fowler, known simply as “Max” to his many friends and colleagues. By this decision, the International Steering Committee emphasized not only the outstanding contribution of Max Fowler as a pioneer in the field of megagauss magnetic field generation, design of generators of magnetic fields and electromagnetic energy, and the application of the generators to various problems of experimental physics, but especially his outstanding contribution to the creation of the International Megagauss Community. International Steering Committee asked Dr. James H. Goforth (Lanl) and Gennady A. Shvetsov (LIH, Russia) to prepare presentations about Max Fowler at the Conference (“Megagauss-XVI”) and to write brief notes about him.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127695195","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":"Basic Configuration of an Indestructible Quasi-Force-Free Magnet with Magnetic Flux Density above 100 T","authors":"G. Shneerson, A. Nemov, A. Nenashev, I. Vecherov, P. Marchenko, A. Lagutkina","doi":"10.1109/MEGAGAUSS.2018.8722671","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722671","url":null,"abstract":"The initial step in the development of an indestructible magnet with a megagauss level is the construction of its two-dimensional basic configuration, which is based on the assumption of continuous current distribution along the radius and the thickness of the winding layer. This problem is considered for a magnet with equilibrated winding layers, which generates field above 100 T. The thickness of the conductors is chosen according to the condition of allowed heating and the boundary of each conductive layer meets the condition of the absence of magnetic flux density normal component. A multi-parameter optimization of the magnetic system is performed with the purpose of achieving the acceptable von Mises stresses in the conductors. The shape of the conducting layers, distance between them and poloidal current in them are varied during optimization. Maxwell's and elasticity equations are solved by the use of ANSYS code at each iteration. The specific features of the optimization process are described, and the results of optimization are presented. The magnets configurations obtained provide the basis for further development of a three-dimensional magnet configuration, where gaps between the coil turns are filled with dielectric.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127516528","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":"Isentropic Compression of Substances by Means of Ultrahigh Magnetic Field of MC-1 Generator in Megabar Pressure Ranges","authors":"Sergey I.Belov, Alexander I.Bykov, Gennady V.Boriskov, Nikolay I.Egorov, Alexey S.Korshunov, Igor V.Makarov, Valery N.Pavlov, Pavel B.Repin, Victor D.Selemir, Ilya S.Strelkov, Oleg M.Surdin, Valentina I.Timareva","doi":"10.1109/MEGAGAUSS.2018.8722667","DOIUrl":"https://doi.org/10.1109/MEGAGAUSS.2018.8722667","url":null,"abstract":"The substances behavior study, and first of all, the study of their equation of states (EOS) at ultrahigh pressures and low temperatures is one of the fundamental and interesting problems of high energy density physics. Nowadays, only the method of isentropic compression effectively allows defining the substance characteristics in low temperatures and multimegabar pressures ranges. To study substance properties in these regimes the isentropic compression by means of an ultrahigh magnetic field of the magneto-cumulative generator MC-1 is applied in VNIIEF. The description of an isentropic compression device based on the MC-1 generator is provided in the paper. There is also the information about a radiographic method to define the compressed substances dimensions. The experimental results of zero isotherms construction up to 6 Mbar pressure of protium and deuterium, hydride lithium LiH and WNiCu 3-2 alloy based on tungsten is presented.","PeriodicalId":207949,"journal":{"name":"2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121914628","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}