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Sample records for k500 superconducting cyclotron

  1. Cryogenic system for VECC K500 superconducting cyclotron

    CERN Document Server

    Pal, G; Bhattacharyya, T K; Bhandari, R K

    2009-01-01

    VEC Centre, Kolkata in India is at an advanced stage of commissioning a K500 superconducting cyclotron. The superconducting coil of the magnet for cyclotron is cooled by liquid helium. Three liquid helium cooled cryopanels, placed inside the Dees of the radiofrequency system, maintain the vacuum in the acceleration region of the superconducting cyclotron. The cryogenic system for magnet for cyclotron has been tested by cooling the coil and energizing the magnet. The cryogenic system for cryopanels has also been tested. Heater and temperature sensor were placed on the liquid helium cold head for cryopanel. The temperature of the cold head was observed to be below 20 K upto a heat load of 11.7 watt.

  2. Magnetic field measurement and correction of VECC K500 superconducting cyclotron

    International Nuclear Information System (INIS)

    Dey, M.K.; Debnath, J.; Bhunia, U.; Pradhan, J.; Rashid, H.; Paul, S.; Dutta, A.; Naser, Z.A.; Singh, V.; Pal, G.; Nandi, C.; Dasgupta, S.; Bhattacharya, S.; Pal, S.; Roy, A.; Bhattacharya, T.; Bhole, R.B.; Bhale, D.; Chatterjee, M.; Prasad, R.; Nabhiraj, P.Y.; Hazra, D.P.; Mallik, C.; Bhandari, R.K.

    2006-01-01

    The VECC K500 superconducting cyclotron magnet is commissioned and magnetic field measurement and correction program was successfully completed in March 2006. Here we report the analysis of the measured field data and subsequent correction of the magnet to improve the field quality. (author)

  3. Study of first harmonic field effects on beam extraction for VEC K500 superconducting cyclotron

    International Nuclear Information System (INIS)

    Dey, M.K.; Debnath, J.; Mallik, C.; Bhandari, R.K.

    2002-01-01

    In superconducting cyclotron large momentum compaction at extraction region makes the turn separation very small. The first harmonic effects on the He +1 beam using simulated magnetic field for VEC K500 cyclotron is reported

  4. Commissioning of the Main Magnet of Kolkata K-500 Superconducting Cyclotron

    CERN Document Server

    Bhandari, Rakesh K

    2005-01-01

    Main magnet of the K-500 superconducting cyclotron at Kolkata has been fully assembled in the cyclotron vault. The assembly includes alpha and beta superconducting coils inside the liquid helium chamber, coil tank for the outer vacuum, liquid nitrogen shield, support links, cryogenic instrumentation and 80 ton magnet frame forming the pill box structure. Cooling of the coils was started in mid-December. It took about three weeks to fill the liquid helium chamber - fully immersing the coils. All the four temperature sensors embedded in the coil are steady at about 4.4K. At this time the liquid nitrogen line for cooling the shield seems to show a leak. So, we are not cooling the shield. The helium liquefier/regrigerator of 200W capacity has been functioning well and so is the network of vacuum jacketted and liquid nitrogen cooled cryogenic transfer lines. Energization of the main magnet will begin soon. Magnetic field measurement set up is in place to start the mapping. In this presentation, our experiences wit...

  5. Design of X-Y steering magnet for extraction beamline of K-500 superconducting cyclotron

    International Nuclear Information System (INIS)

    Naser, Md. Zamal A.; Paul, S.; Bhunia, U.; Pradhan, J.; Dey, M.K.; Nandi, C.; Mallik, C.; Bhandari, R.K.

    2005-01-01

    The K-500 Superconducting Cyclotron is in the advanced stage of commissioning at VEC Centre, Kolkata. This accelerator is designed to accelerate up to maximum 80 MeV/nucleon energy. A X-Y steering magnet is essential to guide this high energy beam into the external high energy beam line. This paper describes the designing and the other related necessary aspects of such a steering magnet. (author)

  6. Radio frequency cavity analysis, measurement, and calibration of absolute Dee voltage for K-500 superconducting cyclotron at VECC, Kolkata

    Energy Technology Data Exchange (ETDEWEB)

    Som, Sumit; Seth, Sudeshna; Mandal, Aditya; Paul, Saikat; Duttagupta, Anjan [Variable Energy Cyclotron Centre, Kolkata (India)

    2013-02-15

    Variable Energy Cyclotron Centre has commissioned a K-500 superconducting cyclotron for various types of nuclear physics experiments. The 3-phase radio-frequency system of superconducting cyclotron has been developed in the frequency range 9-27 MHz with amplitude and phase stability of 100 ppm and {+-}0.2{sup 0}, respectively. The analysis of the RF cavity has been carried out using 3D Computer Simulation Technology (CST) Microwave Studio code and various RF parameters and accelerating voltages ('Dee' voltage) are calculated from simulation. During the RF system commissioning, measurement of different RF parameters has been done and absolute Dee voltage has been calibrated using a CdTe X-ray detector along with its accessories and known X-ray source. The present paper discusses about the measured data and the simulation result.

  7. Radio frequency cavity analysis, measurement, and calibration of absolute Dee voltage for K-500 superconducting cyclotron at VECC, Kolkata

    International Nuclear Information System (INIS)

    Som, Sumit; Seth, Sudeshna; Mandal, Aditya; Paul, Saikat; Duttagupta, Anjan

    2013-01-01

    Variable Energy Cyclotron Centre has commissioned a K-500 superconducting cyclotron for various types of nuclear physics experiments. The 3-phase radio-frequency system of superconducting cyclotron has been developed in the frequency range 9–27 MHz with amplitude and phase stability of 100 ppm and ±0.2 0 , respectively. The analysis of the RF cavity has been carried out using 3D Computer Simulation Technology (CST) Microwave Studio code and various RF parameters and accelerating voltages (“Dee” voltage) are calculated from simulation. During the RF system commissioning, measurement of different RF parameters has been done and absolute Dee voltage has been calibrated using a CdTe X-ray detector along with its accessories and known X-ray source. The present paper discusses about the measured data and the simulation result.

  8. Radio frequency cavity analysis, measurement, and calibration of absolute Dee voltage for K-500 superconducting cyclotron at VECC, Kolkata

    Science.gov (United States)

    Som, Sumit; Seth, Sudeshna; Mandal, Aditya; Paul, Saikat; Duttagupta, Anjan

    2013-02-01

    Variable Energy Cyclotron Centre has commissioned a K-500 superconducting cyclotron for various types of nuclear physics experiments. The 3-phase radio-frequency system of superconducting cyclotron has been developed in the frequency range 9-27 MHz with amplitude and phase stability of 100 ppm and ±0.20, respectively. The analysis of the RF cavity has been carried out using 3D Computer Simulation Technology (CST) Microwave Studio code and various RF parameters and accelerating voltages ("Dee" voltage) are calculated from simulation. During the RF system commissioning, measurement of different RF parameters has been done and absolute Dee voltage has been calibrated using a CdTe X-ray detector along with its accessories and known X-ray source. The present paper discusses about the measured data and the simulation result.

  9. Radio frequency cavity analysis, measurement, and calibration of absolute Dee voltage for K-500 superconducting cyclotron at VECC, Kolkata.

    Science.gov (United States)

    Som, Sumit; Seth, Sudeshna; Mandal, Aditya; Paul, Saikat; Duttagupta, Anjan

    2013-02-01

    Variable Energy Cyclotron Centre has commissioned a K-500 superconducting cyclotron for various types of nuclear physics experiments. The 3-phase radio-frequency system of superconducting cyclotron has been developed in the frequency range 9-27 MHz with amplitude and phase stability of 100 ppm and ±0.2(0), respectively. The analysis of the RF cavity has been carried out using 3D Computer Simulation Technology (CST) Microwave Studio code and various RF parameters and accelerating voltages ("Dee" voltage) are calculated from simulation. During the RF system commissioning, measurement of different RF parameters has been done and absolute Dee voltage has been calibrated using a CdTe X-ray detector along with its accessories and known X-ray source. The present paper discusses about the measured data and the simulation result.

  10. Commissioning of cryogen delivery system for superconducting cyclotron magnet

    International Nuclear Information System (INIS)

    Pal, G.; Nandi, C.; Bhattacharyya, T.K.; Chaudhuri, J.; Bhandari, R.K.

    2005-01-01

    A K-500 superconducting cyclotron is being constructed at VECC Kolkata. The cryogen delivery system distributes liquid helium and liquid nitrogen to the superconducting cyclotron. Liquid helium is required to cool the cyclotron magnet and cryopanels. Liquid nitrogen is used to reduce the capacity of the helium liquefier. This paper describes the system, the current status and the commissioning experiences of cryogen delivery system for cyclotron magnet. (author)

  11. Advances in superconducting cyclotrons at MSU

    International Nuclear Information System (INIS)

    Blosser, H.; Antaya, T.; Au, R.

    1987-01-01

    Intensive work on superconducting cyclotrons began at MSU in late 1973 (a brief earlier study had occurred in the early 1960's) and continues vigorously at present. One large cyclotron, the ''K500'', has been operating for a number of years, a second, the ''K800'', is nearing completion, the first operating tests of its magnet having occurred at the time of the previous conference, and a third, the ''medical cyclotron'', is now also nearing completion with first operation of its magnet expected just after the present conference. These cyclotrons like other superconducting cyclotrons are all dramatically smaller than comparable room temperature machines; overall weight is typically about 1/20th of that of room temperature cyclotrons of the same energy. This large reduction in the quantities of materials is partially offset by added complexity, but finally, a net overall cost savings of 50 to 70 % typically results; as a consequence the superconducting cyclotron is widely viewed as the cyclotron of the future. The thirteen years of experience at MSU involving three of these cyclotrons, together with much important work at other laboratories, gives a rather clear view of the advantages and disadvantages of various design approaches including by now a rather significant period of long term evaluation. This paper reviews highlights of this program. (author)

  12. Superconducting cyclotron deflector conditioning status - an experience with high voltage

    International Nuclear Information System (INIS)

    Ghosh, Subhash; Chattopadhyay, Subrata; Bhattacharjee, Tanushyam; De, Anirban; Paul, Santanu; Pal, Gautam; Saha, Subimal; Mallik, C.; Bhandari, R.K.

    2009-01-01

    In this paper we report about the status of the electrostatic deflector which will be used in K500 superconducting cyclotron at VECC, Kolkata. For extraction of beams from superconducting cyclotron we have to achieve 130 kV/cm. Titanium and tungsten are used for anode and septum respectively. The deflector fits within the median plane of the superconducting magnet. We report here the voltage limit, sparking rates, dark current levels and the effects observed on conditioning. For commissioning of the superconducting cyclotron, the plan is to accelerate Neon beam of 50 MeV/n for which the required extraction voltage is 81 kV/cm and we reached up to 110 kV/cm. The conditioning test chamber is maintained at a pressure of 8.0 x 10 -7 mbar. (author)

  13. Induced radioactivity in air-estimation of ventilation rates at the vault and experimental areas of the proposed K-500 superconducting cyclotron, Calcutta

    International Nuclear Information System (INIS)

    Ravishankar, R.

    1999-01-01

    Guidelines are given for the necessary ventilation rates in vault and experimental areas from radiological safety point of view, for the proposed K-500 super-conducting cyclotron at Calcutta. A method is presented for estimating the amount of short lived radioisotopes like 13 N and 15 O taking the (n,2n) mode of productions. Considering the operating conditions of K-500 machine for the production of maximum neutron flux (300 MeV, 50pnA Li beam on Ta target) the energy differential neutron flux and the energy differential production cross section of 13 N and 15 O have been generated using ALICE-91 computer code. The differential cross sections have been folded with radial neutron flux distribution and then integrated over the entire volume of the cyclotron vault, to obtain the total production of the two radioactive gases. The DAC values have been obtained by considering the immersion dose in a semi-infinite hemispherical cloud. Natural decay and removal due to ventilation have been considered to get the recommended ventilation rates. (author)

  14. A mobile superconducting cyclotron for PET and neutron radiography

    International Nuclear Information System (INIS)

    Griffiths, R.

    1988-01-01

    The report addresses the development of a mobile superconducting cyclotron for PET (positron emission tomography) and neutron radiography. Proposals for an ultralight cyclotron were made by Finlan et al., who suggested a novel technique of utilising a superconducting magnet with RF acceleration and iron sectors contained within the room temperature bore of the magnet. Detailed design of a cyclotron based on this concept has progressed well at Oxford Instruments. The main design priorities were to minimise the weight and power consumption of the cyclotron. The cyclotron required a large amount of shielding to reduce either radiation background levels or stray magnetic field. Thus low background levels of radiation and magnetic field are key design criteria. The superconducting magnet has a mean field of 2.35 Tesla and a room temperature bore diameter of 500 mm. Three pairs of profiled iron sectors placed in the center of the warm bore of the magnet provide an azimuthally varying magnetic field. This permits the use of high beam currents with low background. A novel technique is incorporated to reduce the stray magnetic field and radiation from the cyclotron. The RF system consists of three pairs of resonators mounted within the warm bore of the magnet between the iron sectors. (Nogami, K.)

  15. H-superconducting cyclotron for PET isotope production

    International Nuclear Information System (INIS)

    Smirnov, V.L.; Vorozhtsov, S.B.; Vincent, J.

    2014-01-01

    The scientific design of a 14-MeV H - compact superconducting cyclotron for producing of the 18 F and 13 N isotopes has been developed. Main requirements to the facility as a medical accelerator are met in the design. In particular, the main requirement for the cyclotron was the smallest possible size due to the superconducting magnet. The calculations show that the proposed cyclotron allows extracted beam intensity over 500 μA. To increase system reliability and production rates, an external H - ion source is applied. The choice of the cyclotron concept, design of the structure elements, calculation of the electromagnetic fields and beam dynamics from the ion source to the extraction system were performed.

  16. Superconducting cyclotrons

    International Nuclear Information System (INIS)

    Blosser, H.G.; Johnson, D.A.; Burleigh, R.J.

    1976-01-01

    Superconducting cyclotrons are particularly appropriate for acceleration of heavy ions. A review is given of design features of a superconducting cyclotron with energy 440 (Q 2 /A) MeV. A strong magnetic field (4.6 tesla average) leads to small physical size (extraction radius 65 cm) and low construction costs. Operating costs are also low. The design is based on established technology (from present cyclotrons and from large bubble chambers). Two laboratories (in Chalk River, Canada and in East Lansing, Michigan) are proceeding with construction of full-scale prototype components for such cyclotrons

  17. Design of the injection channel magnets for the K1200 cyclotron

    International Nuclear Information System (INIS)

    Wu, X.Y.; Lawton, D.; Marti, F.; Zeller, A.F.

    2001-01-01

    The beam from the K500 cyclotron is injected radially into the median plane of the K1200 cyclotron where it is stripped inside a dee. Along the injection path, the injected beam traverses large magnetic gradients under the K1200 superconducting coil and on the edge of the hill. To match the injected beam to the eigen-ellipse for the accelerated beam, two magnetic elements are included in the injection channel in the yoke of the K1200 cyclotron. One of them is an active element and the other a conical focusing passive element. This last element must move in the horizontal plane to match the different beam paths. We describe in the paper the beam dynamics calculations as well as the mechanical design and construction of these magnets

  18. Design calculation for the central region of the NSCL 500 MeV superconducting cyclotron

    International Nuclear Information System (INIS)

    Marti, F.; Gordon, M.M.; Chen, M.B.; Salgado, C.; Antaya, T.; Liukkonen, E.

    1982-01-01

    The 500 MeV superconducting cyclotron has three 60 0 dees within the magnet valleys, and the design of the central region is complicated because it must accommodate the inner tips of these dees, the tips of the three intervening dummy dees, and the ion source, all within a very small space. In addition, this cyclotron is designed to operate on harmonics from h=1 to 7, with dee voltages up to 100 kV, and must accelerate a wide variety of heavy ions with turn numbers from n=100 to 600. To satisfy these diverse requirement, the overall plan for the central region calls for the construction and use of many different, but readily interchangeable sets of electrode structures with each set designed for a different range of operating conditions. The procedure for determining the optimum geometry for a set of electrodes involves a converging sequence of tentative designs each of which is tested and improved through a combination of electrolytic tank measurements and orbit computations. For this purpose, the speed and accuracy of the tank measurements have been improved, and the resultant potentials are used in our computer programs to determine whether the ion orbits clear the obstacles successfully, gain energy efficiently, receive adequate vertical focusing, and finally emerge from the central region properly centered. The vertical motion computations are by far the most difficult, and a special effort has been made to obtain satisfactory results

  19. Conceptual design of the superconducting magnet for the 250 MeV proton cyclotron.

    Science.gov (United States)

    Ren, Yong; Liu, Xiaogang; Gao, Xiang

    2016-01-01

    The superconducting cyclotron is of great importance to treat cancer parts of the body. To reduce the operation costs, a superconducting magnet system for the 250 MeV proton cyclotron was designed to confirm the feasibility of the superconducting cyclotron. The superconducting magnet system consists of a pair of split coils, the cryostat and a pair of binary high temperature superconductor current leads. The superconducting magnet can reach a central magnetic field of about 1.155 T at 160 A. The three GM cryocooler with cooling capacities of 1.5 W at 4.5 K and 35 W at 50 K and one GM cryocooler of 100 W at 50 K were adopted to cool the superconducting magnet system through the thermosiphon technology. The four GM cryocoolers were used to cool the superconducting magnet to realize zero evaporation of the liquid helium.

  20. Application of superconductivity in cyclotron construction

    International Nuclear Information System (INIS)

    Blosser, H.G.

    1982-01-01

    This paper reviews major concepts and design features of the new class of cyclotrons which use superconducting coils to provide main magnet excitation. The discussion begins with a brief historical review tracing the evolution of these ''superconducting'' cyclotrons and the impact of this application of superconductivity in pushing back traditional cyclotron construction limits. This is followed by a review of the principal phenomena which come into play to set new limits on the operating regime, and the nature of these limits, some of which arise from orbit properties and some of which result from construction intricacies in the coil and in the rf system. Conclusions anticipate a future widely encompassing role in the application of superconductivity to cyclotron

  1. Neutron skyshine measurement at a K1200 superconducting heavy ion cyclotron using bubble dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, B. [Safety Div., Australian Nuclear Science and Technology Organisation, Menai (Australia); Ronningen, R.M. [Michigan State Univ., National Superconducting Cyclotron Lab., East Lansing, MI (United States); Rossi, P. [Michigan State Univ., Office of Radiation, Chemical and Biological Safety, East Lansing, MI (United States)

    1999-07-01

    Understanding the characteristics of the neutron skyshine radiation is necessary for an accurate assessment of the environmental dose in the vicinity of the containment of a high-energy particle accelerator. At the National Superconducting Cyclotron Laboratory (NSCL), neutron skyshine was measured, using beams of 140 MeV/nucleon {sup 4}He and 80 MeV/nucleon {sup 22}Ne ions from the K1200 superconducting cyclotron. After passing through a radioactive-beam production target, the ion beam stopped in a solid aluminium stopping bar inside of a dipole magnet, resulting in the production of high energy fragmentation as well as evaporation neutrons in the NSCL Analysis Hall. The neutron dose equivalent and energy spectrum at the 1.37 m thick concrete roof of the Analysis Hall, directly above the aluminium target bar (reference point), were estimated, using a spherical 'rem-counter' and a set of seven Bonner-spheres, respectively. The skyshine dose, from neutrons transmitted through 21.5-cm local iron 'shielding' of the dipole magnet and the concrete roof, were evaluated using superheated bubble dosimeters at 50 m, 75 m, 100 m and 115 m from the reference point. The neutron doses beyond the extremity of the NSCL facility were extrapolated from the results of this investigation and were used to predict the exposure to members of the public by considering the operation schedule of the K1200 cyclotron. (authors)

  2. Progress report on the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    Acerbi, E.; Alessandria, F.; Baccaglioni, G.; Bellomo, G.; Birattari, C.; Bosotti, A.; Broggi, F.; Cortesi, G.; DeMartinis, C.; Fabrici, E.; Ferrari, A.; Giove, D.; Giussani, A.; Giussani, W.; Michelato, P.; Pagani, C.; Rivoltella, G.; Rossi, L.; Serafini, L.; Sussetto, A.; Torri, V.; Varisco, G.; Cuttone, G.; Raia, G.; Kai, L.

    1988-01-01

    This paper reports on the construction of the K800 superconducting cyclotron at the University of Milan underway since February 1981. The delay in the construction of the new building and a defect of the weldings of the helium vessel have caused a shift in the project schedule of about two years. Currently, the cyclotron magnet and the cryogenic plant have been completed and installed. First operation of the magnet and magnetic field mapping are to begin shortly

  3. Cyclotron based nuclear science: Progress report, April 1, 1987-March 31, 1988

    International Nuclear Information System (INIS)

    1988-08-01

    This report discusses experiment run on the K500 cyclotron and 88 in cyclotron at Texas AandM University. The main topics of these experiments are: Heavy ion reactions; Nuclear structure and fundamental interactions; Atomic and material science; Nuclear theory; and Superconducting cyclotron and instrumentation

  4. Mechanical design features of the MSU K-800 cyclotron superconducting coil

    International Nuclear Information System (INIS)

    Lawton, D.; Blosser, H.G.; Moskalik, J.M.; Stork, G.A.

    1984-01-01

    The winding of the K-800 cyclotron superconducting magnet coil was completed in late 1983. The windings consist of four separate coils (symmetrical large and small coils on each side of the median plane). The coils are wound in vertical layers in a spiral fashion. The large coils are 32 layers with 2329 total turns each (59,000 feet of wire) and the small coils are 32 layers with 1544 turns each (39,000 feet of wire). The spiral winding was achieved by supporting the first turn of a layer by a set of gradually increasing spacers with subsequent turns supported by previous turns. Winding was done on the 10 foot diameter table vertical lathe. The winding apparatus was mounted on the lathe's tool arm which had an automatic vertical feed to match the spiral path of the wire. The superconducting cable has a retangular cross section (with rounded corners) of dimentions .207 inches x .150 inches. Approximately 200 niobium titanium filaments are contained in a .04 inch x .06 inches copper insert that is soldered (50/50 lead tin) in a slot in the side of the copper conductor substrate

  5. Radiation safety aspects of the AGOR superconducting cyclotron facility

    NARCIS (Netherlands)

    Beijers, JPM; de Meijer, RJ

    1996-01-01

    This paper describes shielding calculations and skyshine estimates for the new AGOR K=600 superconducting cyclotron facility. Both simple, semi-empirical models and Monte-Carlo simulations were used. The calculations are based on a 200 MeV proton beam incident on a trick aluminum target. Also the

  6. Thermal Stabilization of Cryogenic System in Superconducting Cyclotron

    International Nuclear Information System (INIS)

    Shin, Seung Jae; Kim, Kyung Min; Cho, Hyung Hee; Hong, Bong Hwan; Kang, Joon Sun; Ahn, Dong Hyun

    2011-01-01

    Radiology has some useful applications for medical purpose. For cancer therapy, the superconducting cyclotron should generate heavy ion beams. It radiates heavy ion beams to cancer patients. In order to make cyclotron system stable, the cryogenic system which makes superconducting state should work constantly. However, radiation heat transfer of cryogenic system should be considered because liquid helium's boiling point is extremely low and there is huge temperature difference between the cryogenic system and ambient temperature. Accordingly, thermal analysis should be carried out. In this paper, the numerical analysis of the cryogenic system in practical superconducting cyclotron show temperature distribution and suggest the number of coolers using ANSYS Workbench program

  7. Design of RF system for CYCIAE-230 superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Ji, Bin; Fu, Xiaoliang; Cao, Xuelong; Zhao, Zhenlu; Zhang, Tinajue

    2017-05-11

    The CYCIAE230 is a low-current, compact superconducting cyclotron designed for proton therapy. The Radio Frequency system consists of four RF cavities and applies second harmonic to accelerate beams. The driving power for the cavity system is estimated to be approximately 150 kW. The LLRF controller is a self-made device developed and tested at low power using a small-scale cavity model. In this paper, the resonator systems of an S.C. cyclotron in history are reviewed. Contrary to those RF systems, the cavities of the CYCIAE230 cyclotron connect two opposite dees. Two high-power RF windows are included in the system. Each window carries approximately 75 kW RF power from the driver to the cavities. Thus, the RF system for the CY-CIAE230 cyclotron is operated in driven push–pull mode. The two-way amplifier-coupler-cavity systems are operated with approximately the same amount of RF power but 180° out of phase compared with each other. The design, as well as the technical advantage and limitations of this operating mode, of the CYCIAE230 cyclotron RF system is analyzed.

  8. Design of RF system for CYCIAE-230 superconducting cyclotron

    Science.gov (United States)

    Yin, Zhiguo; Ji, Bin; Fu, Xiaoliang; Cao, Xuelong; Zhao, Zhenlu; Zhang, Tinajue

    2017-05-01

    The CYCIAE230 is a low-current, compact superconducting cyclotron designed for proton therapy. The Radio Frequency system consists of four RF cavities and applies second harmonic to accelerate beams. The driving power for the cavity system is estimated to be approximately 150 kW. The LLRF controller is a self-made device developed and tested at low power using a small-scale cavity model. In this paper, the resonator systems of an S.C. cyclotron in history are reviewed. Contrary to those RF systems, the cavities of the CYCIAE230 cyclotron connect two opposite dees. Two high-power RF windows are included in the system. Each window carries approximately 75 kW RF power from the driver to the cavities. Thus, the RF system for the CY-CIAE230 cyclotron is operated in driven push-pull mode. The two-way amplifier-coupler-cavity systems are operated with approximately the same amount of RF power but 180° out of phase compared with each other. The design, as well as the technical advantage and limitations of this operating mode, of the CYCIAE230 cyclotron RF system is analyzed.

  9. Present and future superconducting cyclotrons

    International Nuclear Information System (INIS)

    Nolen, J.A. Jr.

    1987-01-01

    This paper begins with a brief review of the status of present superconducting (SC) cyclotron projects, including the two which are currently operating and the six which are under construction. The next section summarizes the main features shared by five of these machines, while the third section presents recent developments and new concepts introduced in the other three ''second generation'' SC cyclotrons. Projects in early stages of development are discussed in the fourth section

  10. Conceptual design of the RF accelerating cavities for a superconducting cyclotron

    International Nuclear Information System (INIS)

    Maggiore, M.; Calabretta, L.; Di Giacomo, M.; Rifuggiato, D.; Battaglia, D.; Piazza, L.

    2006-01-01

    A superconducting cyclotron accelerating ions up to 250 A MeV, for medical applications and radioactive ions production is being studied at Laboratori Nazionali del Sud in Catania. The radio frequency (RF) system, working in the fourth harmonic, is based on four normal conducting radio frequency cavities operating at 93 MHz. This paper describes an unusual multi-stem cavity design, performed with 3D electromagnetic codes. Our aim is to obtain a cavity, completely housed inside the cyclotron, with a voltage distribution ranging from 65 kV in the injection region to a peak value of 120 kV in the extraction region, and having a low power consumption

  11. Preliminary magnet design for a superconducting separated sector cyclotron

    International Nuclear Information System (INIS)

    Bertrand, P.; Chabert, A.; Duval, M.; Ripouteau, F.

    1992-01-01

    This paper reports that in order to increase the energies available at GANIL, studies on a superconducting separated six straight sector cyclotron for heavy ions with energy up to 500 MeV/A (ions with Q/A = 0.5) have been performed. With a mean injection radius of 2.5 m and an extraction radius of 5 m, the maximum magnetic field on a sector has to be 5T. Each of the six sectors consists of two superconducting main coils (wound around the poles), room temperature iron pole pieces and a large yoke. Due to the broad ranges of energy and ion species, the required field laws are very different and for the most difficult operating point, the induction difference between the injection and ejection radii is about one Tesla. As a consequence, correcting coils have to provide a high field and one unusual point is that the machine will be operated with superconducting trim coils

  12. Electrostatic deflector development at the Chalk River superconducting cyclotron

    International Nuclear Information System (INIS)

    Diamond, W.T.; Mitchel, G.R.; Almeida, J.; Schmeing, H.

    1991-01-01

    An electrostatic deflector is used to extract heavy-ion beans from the Chalk River superconducting cyclotron. Deflector voltages up to 100 kV across a 7 m gap (143 kV/cm) are needed to extract the full range of beams that the cyclotron is designed to accelerate. This goal remains a challenge, but substantial progress has been made over the past year. Voltages over 90 kV have been reliably maintained over a 7.5 mm gap with a magnetic field of 3 T. Voltages of 74 kV have been used with a reduced gap of 4.75 mm (corresponding to a field greater than 150 kV/cm) to extract beams with magnetic fields up to 4.25 T. Major progress was achieved when the authors introduced a water-cooled, negative high-voltage electrode, and changed the sparking plates and the thin septum from molybdenum to stainless steel. Efforts are continuing to attain a field of at least 143 kV/cm over a gap of at least 6 mm width

  13. Rf structure of superconducting cyclotron for therapy application

    International Nuclear Information System (INIS)

    Takekoshi, Hidekuni; Matsuki, Seishi; Mashiko, Katuo; Shikazono, Naomoto.

    1981-01-01

    Advantages of fast neutrons in therapeutical application are now widely recognized. Fast neutrons are generated by bombarding a thick beryllium target with high energy protons and deuterons. The AVF cyclotrons which deliver 50 MeV protons and 25 MeV deuterons are commonly used and are commercially available now. At the treatment usually rotational irradiation is taken to prevent an injury to normal tissue from the high LET effect of fast neutrons. The construction cost of both cyclotrons and isocentric irradiation installation are relatively high, so that the spread of neutron therapy is obstructed. A superconducting cyclotron for neutron therapy application was proposed by a Chalk River group. This low cost design allows the installation to be a dedicated facility located in a hospital, and small size allows installations of the complete cyclotron in a rotatable gantry. The design studies of the superconducting cyclotron based on this idea are going on at Kyoto University. The full scale model experiments for a rf structure of the cyclotron were carried out. (author)

  14. New superconducting cyclotron driven scanning proton therapy systems

    International Nuclear Information System (INIS)

    Klein, Hans-Udo; Baumgarten, Christian; Geisler, Andreas; Heese, Juergen; Hobl, Achim; Krischel, Detlef; Schillo, Michael; Schmidt, Stefan; Timmer, Jan

    2005-01-01

    Since one and a half decades ACCEL is investing in development and engineering of state of the art particle-therapy systems. A new medical superconducting 250 MeV proton cyclotron with special focus on the present and future beam requirements of fast scanning treatment systems has been designed. The first new ACCEL medical proton cyclotron is under commissioning at PSI for their PROSCAN proton therapy facility having undergone successful factory tests especially of the closed loop cryomagnetic system. The second cyclotron is part of ACCEL's integrated proton therapy system for Europe's first clinical center, RPTC in Munich. The cyclotron, the energy selection system, the beamline as well as the four gantries and patient positioners have been installed. The scanning system and major parts of the control software have already been tested. We will report on the concept of ACCEL's superconducting cyclotron driven scanning proton therapy systems and the current status of the commissioning work at PSI and RPTC

  15. Compact superconducting cyclotron C400 for hadron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Jongen, Y.; Abs, M.; Blondin, A.; Kleeven, W.; Zaremba, S.; Vandeplassche, D. [IBA, Chemin du Cyclotron 3, B-1348 Louvain-la-Neuve (Belgium); Aleksandrov, V.; Gursky, S.; Karamyshev, O. [JINR, Joliot-Curie 6, 141980 Dubna, Moscow region (Russian Federation); Karamysheva, G., E-mail: gkaram@nu.jinr.r [JINR, Joliot-Curie 6, 141980 Dubna, Moscow region (Russian Federation); Kazarinov, N.; Kostromin, S.; Morozov, N.; Samsonov, E.; Shirkov, G.; Shevtsov, V.; Syresin, E.; Tuzikov, A. [JINR, Joliot-Curie 6, 141980 Dubna, Moscow region (Russian Federation)

    2010-12-01

    The compact superconducting isochronous cyclotron C400 has been designed by the IBA-JINR collaboration. It will be the first cyclotron in the world capable of delivering protons, carbon and helium ions for cancer treatment. The cyclotron construction is started this year within the framework of the Archade project (Caen, France). {sup 12}C{sup 6+} and {sup 4}He{sup 2+} ions will be accelerated to 400 MeV/uu energy and extracted by the electrostatic deflector, H{sub 2}{sup +} ions will be accelerated to the energy of 265 MeV/uu and extracted by stripping. The magnet yoke has a diameter of 6.6 m, the total weight of the magnet is about 700 t. The designed magnetic field corresponds to 4.5 T in the hills and 2.45 T in the valleys. Superconducting coils will be enclosed in a cryostat; all other parts of the cyclotron will be warm. Three external ion sources will be mounted on the switching magnet on the injection line located below the cyclotron. The main parameters of the cyclotron, its design, the current status of the development work on the cyclotron systems are presented.

  16. A small scale remote cooling system for a superconducting cyclotron magnet

    Science.gov (United States)

    Haug, F.; Berkowitz Zamorra, D.; Michels, M.; Gomez Bosch, R.; Schmid, J.; Striebel, A.; Krueger, A.; Diez, M.; Jakob, M.; Keh, M.; Herberger, W.; Oesterle, D.

    2017-02-01

    Through a technology transfer program CERN is involved in the R&D of a compact superconducting cyclotron for future clinical radioisotope production, a project led by the Spanish research institute CIEMAT. For the remote cooling of the LTc superconducting magnet operating at 4.5 K, CERN has designed a small scale refrigeration system, the Cryogenic Supply System (CSS). This refrigeration system consists of a commercial two-stage 1.5 W @ 4.2 K GM cryocooler and a separate forced flow circuit. The forced flow circuit extracts the cooling power of the first and the second stage cold tips, respectively. Both units are installed in a common vacuum vessel and, at the final configuration, a low loss transfer line will provide the link to the magnet cryostat for the cooling of the thermal shield with helium at 40 K and the two superconducting coils with two-phase helium at 4.5 K. Currently the CSS is in the testing phase at CERN in stand-alone mode without the magnet and the transfer line. We have added a “validation unit” housed in the vacuum vessel of the CSS representing the thermo-hydraulic part of the cyclotron magnet. It is equipped with electrical heaters which allow the simulation of the thermal loads of the magnet cryostat. A cooling power of 1.4 W at 4.5 K and 25 W at the thermal shield temperature level has been measured. The data produced confirm the design principle of the CSS which could be validated.

  17. Overview of the future upgrade of the INFN-LNS superconducting cyclotron

    Science.gov (United States)

    Calabretta, Luciano; Calanna, Alessandra; Cuttone, Giacomo; D'Agostino, Grazia; Rifuggiato, Danilo; Domenico Russo, Antonio

    2017-06-01

    The LNS Superconducting Cyclotron, named “Ciclotrone Superconduttore” (CS), has been in operation for more than 20 years. A wide range of ion species from hydrogen to lead, with energy in the range 10 to 80 AMeV, have been delivered to users. The maximum beam power is limited to 100 W due to the beam dissipation on the electrostatic deflectors. To fulfil the demand of users aiming at studying rare processes in nuclear physics, an upgrade of the cyclotron is necessarily intended to increase the intensity of ion beams with mass lower than 40 a.m.u. up to a power 10 kW. This will be achieved by means of extraction by stripping. This solution needs to replace the cryostat including the superconducting coils. The present capability of the cyclotron will be maintained, i.e. all the ion species allowed by the operating diagram will be available, being extracted by electrostatic extraction. In addition to the high power beams for nuclear physics, it will be possible to produce medical radioisotopes like 211At using an internal target.

  18. A conceptual design of high-temperature superconducting isochronous cyclotron magnet

    International Nuclear Information System (INIS)

    Jiao, F.; Tang, Y.; Li, J.; Ren, L.; Shi, J.

    2011-01-01

    A design of High-temperature superconducting (HTS) isochronous cyclotron magnet is proposed. The maximum magnetic field of cyclotron main magnet reaches 3 T. Laying the HTS coil aboard the magnetic pole will raise the availability of the magnetic Field. Super-iron structure can provide a high uniformity and high gradient magnetic field. Super-iron structure can raise the availability of the HTS materials. Along with the development of High-temperature superconducting (HTS) materials, the technology of HTS magnet is becoming increasingly important in the Cyclotron, which catches growing numbers of scholars' attentions. Based on the analysis of the problems met in the process of marrying superconducting materials with ferromagnetic materials, this article proposes a design of HTS isochronous cyclotron magnet. The process of optimization of magnet and the methods of realizing target parameters are introduced after taking finite element software as analyzing tools.

  19. A CCD camera probe for a superconducting cyclotron

    International Nuclear Information System (INIS)

    Marti, F.; Blue, R.; Kuchar, J.; Nolen, J.A.; Sherrill, B.; Yurkon, J.

    1991-01-01

    The traditional internal beam probes in cyclotrons have consisted of a differential element, a wire or thin strip, and a main probe with several fingers to determine the vertical distribution of the beam. The resolution of these probes is limited, especially in the vertical direction. The authors have developed a probe for their K1200 superconducting cyclotron based on a CCD TV camera that works in a 6 T magnetic field. The camera looks at the beam spot on a scintillating screen. The TV image is processed by a frame grabber that digitizes and displays the image in pseudocolor in real time. This probe has much better resolution than traditional probes. They can see beams with total currents as low as 0.1 pA, with position resolution of about 0.05 mm

  20. Superconducting conversion of the Oak Ridge Isochronous Cyclotron

    International Nuclear Information System (INIS)

    Martin, J.A.; Ball, J.B.; Cleary, E.D.

    1981-01-01

    The superconducting conversion of the Oak Ridge Isochronous Cyclotron (ORIC) will replace the existing aluminum main magnet coils with a NbTi superconducting coil system to provide an increase in magnetic field from 1.9 to 3.3 T. The higher magnetic field will provide a three-fold increase in maximum energy capability of the cyclotron for high mass ions. The conversion will include a new beam extraction system, magnet yoke stiffening to counteract the increased magnetic forces, and minor modifications to the beam transport systems and shielding

  1. Status of the Chalk River superconducting heavy-ion cyclotron

    International Nuclear Information System (INIS)

    Ormrod, J.H.; Bigham, C.B.; Heighway, E.A.; Hoffmann, C.R.; Hulbert, J.A.; Schneider, H.R.

    1982-01-01

    The Chalk River four-sector K=520 superconducting cyclotron is designed to accelerate all ions from lithium (to 50 MeV/u) to uranium (to 10 MeV/u) using a 13 MV tandem Van de Graaff as injector. After an extended shutdown the magnet has been reassembled and field measurements resumed. During the shutdown a ground fault between the superconducting coil and its container was removed, the flutter poles were shimmed and the remaining trim rod holes were bored in them, the 104 trim rods with their holders were installed and the cryostat inner wall was modified to accept the radiofrequency accelerating structure. Experiments on the radiofrequency accelerating system, cryopumps, electrostatic deflector and superconducting windings for the magnetic channel are done in separate test chambers. Recent results and the status of all subsystems are given

  2. Fabrication of beam diagnostic components for Superconducting Cyclotron at Kolkata

    International Nuclear Information System (INIS)

    Roy, S.; Bhattacharya, S.; Das, T.; Bhattacharyya, T.K.; Pal, S.; Pal, G.; Mallik, C.; Bhandari, R.K.

    2009-01-01

    The viewer probe and main probe are used for determining the position and current of charged particles as it is accelerated inside the superconducting cyclotron. The viewer probe is used to visually observe the shape of the charged particle beam inside the cyclotron with the help of a borescope. The main probe measures the distribution of charged particles. The viewer probe and main probe are bellow sealed. They can be positioned with an accuracy of 0.5 mm at different radii within the superconducting cyclotron. M9 slit is placed after the exit flange of the cyclotron. It determines the position of the beam leaving the cyclotron. The beam line has slits, faraday cup, beam viewers, collimators, etc. for beam diagnostics. This paper presents the mechanical design and details of beam diagnostic components. (author)

  3. NORTICA - a new code for cyclotron analysis

    International Nuclear Information System (INIS)

    Gorelov, D.; Johnson, D.; Marti, F.

    2001-01-01

    The new package NORTICA (Numerical ORbit Tracking In Cyclotrons with Analysis) of computer codes for beam dynamics simulations is under development at NSCL. The package was started as a replacement for the code MONSTER developed in the laboratory in the past. The new codes are capable of beam dynamics simulations in both CCF (Coupled Cyclotron Facility) accelerators, the K500 and K1200 superconducting cyclotrons. The general purpose of this package is assisting in setting and tuning the cyclotrons taking into account the main field and extraction channel imperfections. The computer platform for the package is Alpha Station with UNIX operating system and X-Windows graphic interface. A multiple programming language approach was used in order to combine the reliability of the numerical algorithms developed over the long period of time in the laboratory and the friendliness of modern style user interface. This paper describes the capability and features of the codes in the present state

  4. NORTICA—a new code for cyclotron analysis

    Science.gov (United States)

    Gorelov, D.; Johnson, D.; Marti, F.

    2001-12-01

    The new package NORTICA (Numerical ORbit Tracking In Cyclotrons with Analysis) of computer codes for beam dynamics simulations is under development at NSCL. The package was started as a replacement for the code MONSTER [1] developed in the laboratory in the past. The new codes are capable of beam dynamics simulations in both CCF (Coupled Cyclotron Facility) accelerators, the K500 and K1200 superconducting cyclotrons. The general purpose of this package is assisting in setting and tuning the cyclotrons taking into account the main field and extraction channel imperfections. The computer platform for the package is Alpha Station with UNIX operating system and X-Windows graphic interface. A multiple programming language approach was used in order to combine the reliability of the numerical algorithms developed over the long period of time in the laboratory and the friendliness of modern style user interface. This paper describes the capability and features of the codes in the present state.

  5. Design study of the KIRAMS-430 superconducting cyclotron magnet

    International Nuclear Information System (INIS)

    Kim, Hyun Wook; Kang, Joonsun; Hong, Bong Hwan; Jung, In Su

    2016-01-01

    Design study of superconducting cyclotron magnet for the carbon therapy was performed at the Korea Institute of Radiological and Medical Science (KIRAMS). The name of this project is The Korea Heavy Ion Medical Accelerator (KHIMA) project and a fixed frequency cyclotron with four spiral sector magnet was one of the candidate for the accelerator type. Basic parameters of the cyclotron magnet and its characteristics were studied. The isochronous magnetic field which can guide the "1"2C"6"+ ions up to 430 MeV/u was designed and used for the single particle tracking simulation. The isochronous condition of magnetic field was achieved by optimization of sector gap and width along the radius. Operating range of superconducting coil current was calculated and changing of the magnetic field caused by mechanical deformations of yokes was considered. From the result of magnetic field design, structure of the magnet yoke was planned.

  6. Design study of the KIRAMS-430 superconducting cyclotron magnet

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Wook; Kang, Joonsun, E-mail: genuinei@kirams.re.kr; Hong, Bong Hwan; Jung, In Su

    2016-07-01

    Design study of superconducting cyclotron magnet for the carbon therapy was performed at the Korea Institute of Radiological and Medical Science (KIRAMS). The name of this project is The Korea Heavy Ion Medical Accelerator (KHIMA) project and a fixed frequency cyclotron with four spiral sector magnet was one of the candidate for the accelerator type. Basic parameters of the cyclotron magnet and its characteristics were studied. The isochronous magnetic field which can guide the {sup 12}C{sup 6+} ions up to 430 MeV/u was designed and used for the single particle tracking simulation. The isochronous condition of magnetic field was achieved by optimization of sector gap and width along the radius. Operating range of superconducting coil current was calculated and changing of the magnetic field caused by mechanical deformations of yokes was considered. From the result of magnetic field design, structure of the magnet yoke was planned.

  7. Analysis for liquid cryogen spillage in the superconducting cyclotron building at VECC

    CERN Document Server

    Roy S ,; Pal, G; Bhandari, R K

    2009-01-01

    The cryogenic system uses liquid helium and liquid nitrogen to cool the superconducting cyclotron magnet and its cryopanels. In order to assess safety scenarios subsequent to an unusual leakage of cryogens from the system, a deterministic analysis has been carried out to estimate the variation of oxygen concentration with time at several locations of superconducting cyclotron building. The entire process is simulated assuming evaporated cryogens mixes instantaneously with air in the confined space, the ventilation system of the cyclotron building is operational, fresh air continuously enters the confined volume and mixes instantaneously with air in the confined space.

  8. First years of operation of the LNS superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Rifuggiato, D.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rovelli, A. [Instituto Nazionale di Fisica Nucleare, Lab. Nazionali del Sud, Catania (Italy)

    1999-07-01

    The K800 Superconducting Cyclotron was commissioned in 1994 and has been in continuous operation since then. In 1996 many efforts were made to reach a condition of reliable operation. Several ion types have been accelerated and delivered to experimental halls. The demand for different beams has given the opportunity to explore several regions of the operating diagram of the machine: different magnetic field values have been set, as well as several RF frequencies have been used. The results demonstrate that the Cyclotron allows to accomplish a large variety of nuclear physics experiments, even if the maximum performance has not yet been achieved. A few sub-systems are being upgraded in view of the 'high intensity' operation (which is required for radioactive beam production) and in order to reach the maximum performance: upgrading is planned on the RF system and on the electrostatic deflectors. A new axial injection system has been designed to operate the machine in stand-alone mode. (authors)

  9. First years of operation of the LNS superconducting cyclotron

    International Nuclear Information System (INIS)

    Rifuggiato, D.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rovelli, A.

    1999-01-01

    The K800 Superconducting Cyclotron was commissioned in 1994 and has been in continuous operation since then. In 1996 many efforts were made to reach a condition of reliable operation. Several ion types have been accelerated and delivered to experimental halls. The demand for different beams has given the opportunity to explore several regions of the operating diagram of the machine: different magnetic field values have been set, as well as several RF frequencies have been used. The results demonstrate that the Cyclotron allows to accomplish a large variety of nuclear physics experiments, even if the maximum performance has not yet been achieved. A few sub-systems are being upgraded in view of the 'high intensity' operation (which is required for radioactive beam production) and in order to reach the maximum performance: upgrading is planned on the RF system and on the electrostatic deflectors. A new axial injection system has been designed to operate the machine in stand-alone mode. (authors)

  10. Characteristics of possible beam losses in superconducting cyclotron

    International Nuclear Information System (INIS)

    Pradhan, J.; Paul, Santanu; Debnath, Jayanta; Dutta, Atanu; Bhunia, Uttam; Naser, Md. Zamal Abdul; Singh, Vinay; Agrawal, Ankur; Dey, Malay Kanti

    2015-01-01

    In a compact superconducting cyclotron large coherent oscillation and off-centering of the beam may cause large amount of beam loss. The off-centered beam may hit the beam chamber wall prohibiting extraction of the beam. Or it may hit the RF liner surfaces due to vertical blow-up across various resonances during acceleration. The vertical shift of beam caused by the mis-alignment gradually moves the beam out of geometrical median plane eventually leading to internal beam losses. The loss of isochronisms results the reduction of beam intensity depending on the particle phase history. Small field perturbations generated by trim coils have been used to identify the beam loss mechanisms in the superconducting cyclotron at out centre. Besides, the beam loss due to interaction of accelerating ions with residual gases is also discussed. The beam profile obtained from differential and three finger probes gives a clear insight of the loss-mechanism. The paper describes different beam losses observed in the cyclotron with corresponding beam profiles under different field perturbations, Special emphasis is given on characteristics features of beam-current profile to identify the cause of beam loss. (author)

  11. The superconducting separated orbit cyclotron TRITRON

    International Nuclear Information System (INIS)

    Trinks, U.

    1984-01-01

    At the Munich 13 MV-Tandem Laboratory the TRITRON is under development, which will be the prototype of a superconducting separated orbit cyclotron for acceleration of heavy ions with 0.04 or approx.20) of the revolution frequency. Thus the frequency range for acceleration of ions with different revolution frequency can be kept small (+-3%). The magnets as well as the cavities are contained in the same cavity. (orig.)

  12. Magnetic field optimisation and orbit calculation for VEC superconducting cyclotron

    International Nuclear Information System (INIS)

    Debnath, J.; Dey, M.K.; Mallik, C.; Bhandari, R.K.

    2003-01-01

    At VECC, Kolkata preparations are underway to measure the magnetic field of the cyclotron. Also once the superconducting cyclotron is assembled prediction of beam related parameters will be a very important exercise to carry out. Considering this the beam behaviour in the cyclotron will be crucial to achieve these goals. The present paper deals with the efforts in this direction and using a test beam of He 1+ 20 MeV/n the trim coil currents, the tune variation and the (r,Pr) behaviour of the central trajectory

  13. Beam transfer lines for the Tandem-superconducting cyclotron at Lab. Nazionale del Sud

    International Nuclear Information System (INIS)

    Calabretta, L.; Cuttone, G.; DiBernardo, P.; Giove, D.; Raia, G.; Yan, C.; Cao, L.; Liu, K.

    1988-01-01

    At the L.N.S. an MP-Tandem will be used as injector for the Superconducting Cyclotron. This paper describes the handling beam system for the Superconducting Cyclotron. All the lines are designed to be achromatic. Home made beam profile monitor is the main diagnostic device and its design and preliminary tests are presented. The distributed computer control for all the beam lines and bunching system is described too. The status of beam transfer line from tandem to S.C. and of bunching system is presented

  14. Superconducting cyclotron magnet coil short

    International Nuclear Information System (INIS)

    Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

    1982-01-01

    In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

  15. Cryogenic system of the prototype of the superconducting magnet for a deuteron cyclotron-1

    International Nuclear Information System (INIS)

    Alenitskij, Yu.G.; Buzdavin, A.P.; Vasilenko, A.T.

    1987-01-01

    The results achieved in developing a cryogenic system for the superconducting magnet of the deuteron cyclotron are described. The cryogenic system consists of a liquefier-refrigerator with the output 40 l.h, or 150 W of power taken off at 4.5 K, a satellite refrigerator, a cryostat of the superconductiong magnet coil and vessels for liquid nitrogen and helium. Now auxiliary equipment is being mounted and the main parts of the magnet are being manufatured

  16. Initial field measurements on the Chalk River superconducting cyclotron

    International Nuclear Information System (INIS)

    Ormrod, J.H.; Chan, K.C.; Hill, J.H.

    1980-12-01

    The midplane magnetic field of the Chalk River superconducting cyclotron has been mapped in detail over the full operating range of 2.5 to 5 tesla. The field measuring apparatus is described and results given include measurements of the field stability, reproducibility and harmonic content. (author)

  17. Magnet field design considerations for a high energy superconducting cyclotron

    International Nuclear Information System (INIS)

    Botman, J.I.M.; Craddock, M.K.; Kost, C.J.; Richardson, J.R.

    1983-08-01

    This paper reports the pole shape designs for a two stage superconducting isochronous cyclotron combination (CANUCK) to accelerate 100 μA proton beams to 15 GeV. The pole shape of the 15 sectors of the first stage 3.5 GeV proton cyclotron provides isochronism over the full energy range and a constant axial tune over all but the lowest energies. Progress on the pole design of the 42 sector 15 GeV second stage is also reported. The magnetic fields are computed from the current distribution of the superconducting coils and the infinitely thin current sheets simulating the fully saturated poles. A least squares method is used to minimize deviations from isochronism by adjusting the size of various elemental shim coils placed around the main coil. The method to obtain the desired axial tune is described

  18. A code for the correction of field imperfections in iron-core superconducting magnets by shimming of iron

    International Nuclear Information System (INIS)

    Pradhan, J.; Bhunia, U.; Dey, M.K.; Mallik, C.; Bhandari, R.K.

    2005-01-01

    The magnetic field measurement of the median plane of K500 superconducting cyclotron at VECC have been carried out. A code has been developed using the mathematical software to calculate the magnetic field distribution for an arbitrary shaped saturated iron piece, and the various harmonics therein

  19. Control philosophy and diagnostic systems of Superconducting Cyclotron

    International Nuclear Information System (INIS)

    Roy, Anindya; Bhattacharjee, Tanushyam; Chaddha, N.; Bhole, R.B.; Pal, Sarbajit; Samanta, N.C.; Dutta, C.D.; Mukhopadhyay, B.; Panda, U.S.; Sarkar, B.; Nabhiraj, P.Y.; Sarkar, D.

    2009-01-01

    The control system has the primary task of monitoring and control of all the important parameters of a machine comprises of various sub-systems. The paper describes the philosophy of the distributed control system of Superconducting Cyclotron implemented with the support of reliable and fast control network. The paper also describes the field hardware interfaced with various software platforms at different levels of individual sub-systems e.g. Main Magnet Power Supply, Trim-coil Power Supplies, He Liquefier/Refrigerator Plant, Cryogen Delivery System, RF System, ECR Ion source, Vacuum System, Radiation Monitoring System, Alarm Annunciation System, LCW System of SC Cyclotron. The database management system facilitating the exchange of control data among the sub-systems, serving as primary source of information to understand the behavior of the cyclotron, is also discussed. A brief description of various beam diagnostic instruments and their respective control systems e.g. Main Probe, Borescope, Beam viewer, Magnetic channel control system, Beam line slit control system, are briefly described. (author)

  20. New development of advanced superconducting electron cyclotron resonance ion source SECRAL (invited)

    International Nuclear Information System (INIS)

    Zhao, H. W.; Sun, L. T.; Zhang, X. Z.; Guo, X. H.; Zhao, H. Y.; Feng, Y. C.; Li, J. Y.; Ma, H. Y.; Ma, B. H.; Wang, H.; Li, X. X.; Xie, D. Z.; Lu, W.; Cao, Y.; Shang, Y.

    2010-01-01

    Superconducting electron cyclotron resonance ion source with advance design in Lanzhou (SECRAL) is an 18-28 GHz fully superconducting electron cyclotron resonance (ECR) ion source dedicated for highly charged heavy ion beam production. SECRAL, with an innovative superconducting magnet structure of solenoid-inside-sextupole and at lower frequency and lower rf power operation, may open a new way for developing compact and reliable high performance superconducting ECR ion source. One of the recent highlights achieved at SECRAL is that some new record beam currents for very high charge states were produced by 18 GHz or 18+14.5 GHz double frequency heating, such as 1 e μA of 129 Xe 43+ , 22 e μA of 209 Bi 41+ , and 1.5 e μA of 209 Bi 50+ . To further enhance the performance of SECRAL, a 24 GHz/7 kW gyrotron microwave generator was installed and SECRAL was tested at 24 GHz. Some promising and exciting results at 24 GHz with new record highly charged ion beam intensities were produced, such as 455 e μA of 129 Xe 27+ and 152 e μA of 129 Xe 30+ , although the commissioning time was limited within 3-4 weeks and rf power only 3-4 kW. Bremsstrahlung measurements at 24 GHz show that x-ray is much stronger with higher rf frequency, higher rf power. and higher minimum mirror magnetic field (minimum B). Preliminary emittance measurements indicate that SECRAL emittance at 24 GHz is slightly higher that at 18 GHz. SECRAL has been put into routine operation at 18 GHz for heavy ion research facility in Lanzhou (HIRFL) accelerator complex since May 2007. The total operation beam time from SECRAL for HIRFL accelerator has been more than 2000 h, and 129 Xe 27+ , 78 Kr 19+ , 209 Bi 31+ , and 58 Ni 19+ beams were delivered. All of these new developments, the latest results, and long-term operation for the accelerator have again demonstrated that SECRAL is one of the best in the performance of ECR ion source for highly charged heavy ion beam production. Finally the future development

  1. Project of the JAERI superconducting AVF cyclotron for applications in biotechnology and materials science

    International Nuclear Information System (INIS)

    Miyawaki, Nobumasa; Kurashima, Satoshi; Okumura, Susumu; Chiba, Atsuya; Agematsu, Takashi; Kamiya, Tomihiro; Kaneko, Hirohisa; Nara, Takayuki; Saito, Yuichi; Ishii, Yasuyuki; Sakai, Takuro; Mizuhashi, Kiyoshi; Fukuda, Mitsuhiro; Yokota, Watalu; Arakawa, Kazuo

    2005-01-01

    A project for expanding TIARA (Takasaki Ion accelerators for Advanced Radiation Application) facilities of JAERI has been proposed to broaden application region of biotechnology and materials science. As a result of the investigation of TIARA facility user's request, energy increase up to more than 100 MeV/n for heavy ions and up to 300 MeV for proton are strongly required. The magnet of a superconducting AVF cyclotron with a K number of 900 has been designed to cope with acceleration of both 150 MeV/n heavy ions and 300 MeV protons. The lower limit of energies has been investigated to overlap the energy region covered by the JAERI AVF cyclotron, required to increase beam time for present users. We have designed a beam transport system to satisfy various requirements of the applications. (author)

  2. Foil changer for the Chalk River superconducting cyclotron

    International Nuclear Information System (INIS)

    Hoffmann, C.R.; Kilborn, R.I.; Mouris, J.E.; Proulx, D.R.; Weaver, J.F.

    1985-01-01

    Capture of an injected beam in the Chalk River superconducting cyclotron requires that a carbon stripping foil be accurately placed in a dee to intercept the incoming beam. Foil radial position must be precisely adjustable and foils must be easily replaced. A foil changing apparatus has been designed, built and tested to meet these requirements. The main components are a supply magazine, a transport system, and unloading and loading mechanisms. The magazine is on top of the cyclotron. It holds 300 foils and can be isolated from machine vacuum for refilling. Each foil is mounted on a stainless steel frame. A stainless steel roller chain fitted with 33 copper sleeves (shrouds) carries foils, one per shroud, down a dee stem to the midplane. A 12-bit absolute optical shaft encoder senses foil position. To replace a foil a shroud is positioned at the top of the cyclotron, a foil is removed, and another is transferred from the magazine to the empty shroud. Three stepping motors and associated electronics provide mechanical drive and are interfaced with a CAMAC control system

  3. Axial injection in Orsay superconducting cyclotron

    International Nuclear Information System (INIS)

    Depauw, J.; Kugler, M.F.; Legoff, A.; Potier, J.C.; Richomme, A.; Skowron, R.; Mandrillon, P.; Schapira, J.P.

    1983-01-01

    The compact superconducting cyclotron currently planned at IPN at Orsay is designed for light ion acceleration together with heavy ion acceleration. From the beginning, for this reason, a central geometry able to receive an inflector (to 90deg C) allowing the axial injection of low energy ion beams given by an outer source. The present study is aimed at showing the technical feasibility of theoretical results obtained on axial injection. First experimental study has been made of spatial repartition in three dimensions of electric potential developed by a central geometry of 3 electrodes. Then, the electric study of an electrostatic mirror has been made [fr

  4. Design study of an ultra-compact superconducting cyclotron for isotope production

    Science.gov (United States)

    Smirnov, V.; Vorozhtsov, S.; Vincent, J.

    2014-11-01

    A 12.5 MeV, 25 μA, proton compact superconducting cyclotron for medical isotope production has been designed and is currently in fabrication. The machine is initially aimed at producing 13N ammonia for Positron Emission Tomography (PET) cardiology applications. With an ultra-compact size and cost-effective price point, this system will offer clinicians unprecedented access to the preferred radiopharmaceutical isotope for cardiac PET imaging. A systems approach that carefully balanced the subsystem requirements coupled to precise beam dynamics calculations was followed. The system is designed to irradiate a liquid target internal to the cyclotron and to minimize the need for radiation shielding. The main parameters of the cyclotron, its design, and principal steps of the development work are presented here.

  5. Foil changer for the Chalk River superconducting cyclotron

    International Nuclear Information System (INIS)

    Hoffmann, C.R.; Kilborn, R.I.; Mouris, J.F.; Proulx, D.R.; Weaver, J.F.

    1985-01-01

    Capture of an injected beam in the Chalk River superconducting cyclotron requires that a carbon stripping foil be accurately placed in a dee to intercept the incoming beam. Foil radial position must be precisely adjustable and foils must be easily replaced. A foil changing apparatus has been designed, built and tested to meet these requirements. The main components are a supply magazine, a transport system, and unloading and loading mechanisms. The magazine is on top of the loading mechanisms. The magazine is on top of the cyclotron. It holds 300 foils and can be isolated from machine vacuum for refilling. Each foil is mounted on a stainless steel frame. A stainless steel roller chain fitted with 33 copper sleeves (shrouds) carries foils, one per shroud, down a dee stem to the midplane. A 12-bit absolute optical shaft encoder senses foil position. To replace a foil a shroud is positioned at the top of the cyclotron, a foil is removed, and another is transferred from the magazine to the empty shroud. Three stepping motors and associated electronics provide mechanical drive and are interfaced with a CAMAC control system

  6. Status of the Catania tandem as injector of the superconducting cyclotron

    International Nuclear Information System (INIS)

    Ciavola, G.; Cuttone, G.; Raia, G.

    1990-01-01

    The Catania LNS tandem facility is operating since 1984. The status and the main modifications of the accelerator during these years are described and the performance obtained is reported. A superconducting cyclotron will be installed at the LNS facility as tandem booster; the main progress is presented. (orig.)

  7. Special features of radio-frequency system for the superconducting cyclotron at VECC

    International Nuclear Information System (INIS)

    Som, S.

    2009-01-01

    The Radio-frequency system of Superconducting (Sc) cyclotron consists of three accelerating electrodes, called Dees, located in the valleys of the magnet at 120 degree apart between each other. It has been developed in the frequency range of 9 - 27 MHz with amplitude and phase stability of 100 ppm and ±0.5 degC. Each dee along with half-wave coaxial cavity develops peak voltage of 100kV having fed with rf power 80 kW from each of the three high power final rf amplifiers. Three numbers of Dee-cavities as well as three numbers of amplifier cavities are tuned by moveable sliding short. The tapered inner conductor (under vacuum) of the main Dee-cavity has been used to minimize power dissipation in the cavity and also to avoid mode interference. Each of the four identical Bridge-T network in the grid of each amplifier is driven with rf power of 150 watts. The amplifier is based on Eimac 4CW - 150000E tetrode and is operated in class-AB mode with power gain 22 dB. It requires dc power supplies (P/S) like, Filament P/S 15.5V/215A, Grid P/S -200V to -500V, Anode P/S 20kV/22.5A and Screen P/S 1.5kV/lA, at its four terminals. A PC-based stepper motor controlled sliding-short movement system is used for tuning the cavities at different frequencies. The closed-loop amplitude and phase regulators are based on RF modulator and I and Q modulation technique respectively. Dee voltage pick-off signals are used as feedback. A PLC-based interlock system protects the rf system as well as operating personnel. Measurements of rf parameters at various resonant frequencies of the amplifier cavity have been done. The frequency response of the input circuit of the amplifier has been measured using VNA. The warm rf test of the amplifier performed well with 70kW output power at 50 Ohm water-cooled dummy load. (author)

  8. Orsay cyclotron design with superconducting coils and the associated accelerating unit

    International Nuclear Information System (INIS)

    1983-06-01

    This report ends the theoretical and technical studies of the project of new accelerating unit proposed by IPN at Orsay. The isochronous cyclotron with superconducting coils is coupled to two different injections: an axial one with polarized or not ion sources for light ions or multicharged ion sources for heavy ions; a radial injection from the reviewed tandem MP13Met. The following points are underlined: 1) the specificity of the machine 2) the theoretical and technical feasibility of a compact high frequency accelerating system suited to this type of machine 3) the development of an extraction device of the beam 4) the feasibility of an axial injection along the optical axis coupled to a unique central region of the cyclotron 5) the criterions to define, the choices to make to get a radial injection of the beam coming from the tandem in the cyclotron [fr

  9. Beam dynamics prior to extraction in Kolkata superconducting cyclotron

    International Nuclear Information System (INIS)

    Paul, S.; Debnath, J.; Dey, M.K.; Mallik, C.; Bhandari, R.K.

    2011-01-01

    The Kolkata Superconducting Cyclotron has already accelerated test beams up to its extraction radius. Efforts are underway to extract the internal beam with the aid of the various extraction elements. A detailed study of the accelerated beams dynamics has been carried out to ensure that before extraction, optimum turn separation is achieved and the beam does not cross the harmful third order coupling resonance, while keeping distortions to a manageable levels. This paper discusses those results and the studies conducted. (author)

  10. A light, superconducting H- cyclotron for medical diagnostics and neutron radiography

    International Nuclear Information System (INIS)

    Finlan, M.F.; Kruip, M.; Wilson, M.N.

    1987-01-01

    Oxford Instruments, working in close collaboration with Amersham International are developing a compact, lightweight, low radiation field superconducting cyclotron. The combination of superconductivity, H - acceleration and no internal yoke as such makes this possible. It is intended for use as a generator of short half lived isotopes for use in hospitals for PET and other imaging procedures, for use in industrial PET imaging, and as a neutron generator for neutron radiography. With a weight of 2000 kg, it is transportable and comparitively easy to handle and is capable in the 17 MeV version of generating 1.8 10 13 neutrons/second for neutron radiography. (author)

  11. A study of a superconducting heavy ion cyclotron as a post accelerator for the CRNL MP Tandem

    International Nuclear Information System (INIS)

    Fraser, J.S.; Tunnicliffe, P.R.

    1975-08-01

    A novel design for a heavy ion cyclotron is described utilizing superconducting coils. Acting as a post accelerator for the CRNL MP Tandem accelerator, the proposed cyclotron is capable of producing an output energy of 10 MeV/u and intensities up to approximately 10 10 particles/s for uranium. (E.C.B.)

  12. Results of RIKEN superconducting electron cyclotron resonance ion source with 28 GHz.

    Science.gov (United States)

    Higurashi, Y; Ohnishi, J; Nakagawa, T; Haba, H; Tamura, M; Aihara, T; Fujimaki, M; Komiyama, M; Uchiyama, A; Kamigaito, O

    2012-02-01

    We measured the beam intensity of highly charged heavy ions and x-ray heat load for RIKEN superconducting electron cyclotron resonance ion source with 28 GHz microwaves under the various conditions. The beam intensity of Xe(20+) became maximum at B(min) ∼ 0.65 T, which was ∼65% of the magnetic field strength of electron cyclotron resonance (B(ECR)) for 28 GHz microwaves. We observed that the heat load of x-ray increased with decreasing gas pressure and field gradient at resonance zone. It seems that the beam intensity of highly charged heavy ions with 28 GHz is higher than that with 18 GHz at same RF power.

  13. Construction and assembling of the trim coils for the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    Baccaglioni, G.; Cartegni, G.C.; Fusetti, M.; Gini, L.; Grilli, L.

    1986-01-01

    This paper presents the main characteristics of the trim coils realized for the heavy ions superconducting cyclotron under construction at the Milan University. The guidelines in the choice of the conductor size, of the insulation and cooling parameters are discussed in some details. The main operations in the coils construction, as winding, impregnation, electrical tests and assembling, are described

  14. Development of an Ethernet enabled microcontroller based module for Superconducting Cyclotron ECR beam line control

    International Nuclear Information System (INIS)

    Chatterjee, M.; Koley, D.; Nabhiraj, P.Y.

    2012-01-01

    An Ethernet enabled control and data acquisition module is developed for remote control and monitoring of the ECR beam line equipment of the Superconducting Cyclotron. The PIC microcontroller based module supports multiple general purpose analog and digital inputs and outputs for interfacing with various equipments and an embedded web server. The remote monitoring and control of the equipment are achieved through the web based user interface. The user authenticated access to control parameters and module configuration parameters ensures the operational safety of the equipment under control. This module is installed in Superconducting Cyclotron ECR beam line for the control and monitoring of vacuum pumping modules, comprising of pumps, gate valves and dual vacuum gauges. The installation of these modules results in a distributed control with localised field cabling and hence better fault diagnosis. (author)

  15. Development of an 18 GHz superconducting electron cyclotron resonance ion source at RCNP.

    Science.gov (United States)

    Yorita, Tetsuhiko; Hatanaka, Kichiji; Fukuda, Mitsuhiro; Kibayashi, Mitsuru; Morinobu, Shunpei; Okamura, Hiroyuki; Tamii, Atsushi

    2008-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source has recently been developed and installed in order to extend the variety and the intensity of ions at the RCNP coupled cyclotron facility. Production of several ions such as O, N, Ar, Kr, etc., is now under development and some of them have already been used for user experiments. For example, highly charged heavy ion beams like (86)Kr(21+,23+) and intense (16)O(5+,6+) and (15)N(6+) ion beams have been provided for experiments. The metal ion from volatile compounds method for boron ions has been developed as well.

  16. Test and calibration of the magnetic measurement system for the Superconducting Cyclotron at LNS, Catania

    International Nuclear Information System (INIS)

    Giove, D.; Rossi, L.; Gmaj, P.; LoMonaco, L.; Raia, G.

    1992-01-01

    The apparatus for magnetic measurements before commissioning of the Superconducting Cyclotron is presented. This is a fast system designed for the systematic mapping of cyclotron fields. A search coil measures the field variation by scanning the median plane radially. The absolute value of the field is measured by NMR probes placed at the cyclotron centre and at the RF cavity holes. Accounting for dead times (coil return, drift measurement); the conservative estimate was made of measuring one full map per hour, with an azimuthal step of 1 o . A brief description of the software used and probe calibration data are included. (author) 4 refs.; 1 fig.; 1 tab

  17. Building of radio frequency cavity for Superconducting Cyclotron

    International Nuclear Information System (INIS)

    Ahammed, M.; DuttaGupta, A.; Mandal, B.Ch.; Saha, S.; Bhattacharya, P.; Manna, B.; Hembrom, B.; Murmu, S.; Sur, S.; Murali, S.; Chaudhuri, J.; Bhandari, R.K.

    2009-01-01

    Full text: RF cavity for Superconducting Cyclotron is a room temperature cavity having 10 m tall coaxial structure placed symmetrically above and below the median plane. The structure is made of copper and operates within the frequency range of 9 to 27 MHz. The frequency is varied with the help of sliding shorts, which moves up and down. Part of the cavity is in air and rest is in vacuum. After fabrication of individual components, assembly of sub-system has been started by carrying out numeral critical (around 500 joints approx.) soldering and brazing joints of which some of them are located within centimeter of distance. All these joints were tested for vacuum and water sealing including many temporary joints sealed by O rings and C seals. Main criticalities involve in fabricating these sub-assemblies are maintaining dimensional accuracies, concentricity and parallelism. Moreover challenges faced during transportation and handling of this subassembly while carrying out soldering and actual site assembly, were overcome by employing several specially designed fixtures. Fixtures were used to control distortion that would take place during soldering and brazing and to avoid any damage which is likely to occur because of less mechanical strength of soldering and brazing joint. This paper highlights the above difficulties and challenges faced during the actual site assembly of the whole RF system because of its limited accessibility, compactness, requirements of upper and lower resonator cavity to be symmetric and ultra cleanliness. (author)

  18. The operator view of the Superconducting Cyclotron at LNS Catania

    International Nuclear Information System (INIS)

    Giove, D.; Cuttone, G.; Rovelli, A.

    1992-01-01

    The upper level of a distributed control system designed for the Superconducting Cyclotron (SC), will be discussed. In particular, we will present a detailed description of the operator view of this accelerator along with the tools for I/O points management, data representations, data archiving and retrieval. A dedicated program, developed by us, working under X-Window will be described as a starting point for a new man-machine interface approach in small laboratories opposed to the first industrial available packages. (author)

  19. Production of highly charged heavy ions by 18 GHz superconducting electron cyclotron resonance at Research Center for Nuclear Physics.

    Science.gov (United States)

    Yorita, Tetsuhiko; Hatanaka, Kichiji; Fukuda, Mitsuhiro; Kibayashi, Mitsuru; Morinobu, Shunpei; Okamura, Hiroyuki; Tamii, Atsushi

    2010-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source has been installed as a subject of the azimuthally varying field cyclotron upgrade project (K. Hatanaka et al., in Proceedings of the 17th International Conference on Cyclotrons and Their Applications, Tokyo, Japan, 18-22 October 2004, pp. 115-117), in order to increase beam currents and to extend the variety of ions. The production development of several ions has been performed since 2006 and some of them have already been used for user experiments [T. Yorita et al., Rev. Sci. Instrum. 79, 02A311 (2008)]. Further optimizations for each component such as the material of plasma electrode, material, and shape of bias probe and mirror field have been continued and more intense ion beams have been obtained for O, N, and Ar. For the purpose of obtaining highly charged Xe with several microamperes, the optimization of position and shape of plasma electrode and bias disk has also been done and highly charged Xe(32+) beam has been obtained successfully.

  20. Superconducting sector magnet for the deuteron cyclotron DC-1

    International Nuclear Information System (INIS)

    Alenitskij, Y.G.; Vasilenko, A.T.; Zaplatin, N.L.; Mironov, S.V.; Morozov, N.A.; Pryanichnikov, V.I.; Samsonov, E.V.; Sukhanov, V.I.; Chesnov, A.F.; Chesnova, S.I.

    1992-01-01

    In this paper the results of calculations of a superconducting magnet with a cold pole for a cyclotron to deuteron energy 100 MeV are presented. The maximum induction in the magnet is 4.5 T, stored energy 5 MJ, mean current density in coil 9 · 10 7 A/m 2 . The scheme and main parameters of the magnet protection system and cryogenic provision system are described. The results of calculation of magnetic and thermal forces acting on the coil and its case are presented. The status of the manufacture of the magnetic system elements is considered

  1. Neutron radiography using a transportable superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Allen, D.A. (School of Physics and Space Research, University of Birmingham, Birmingham, B15 2TT (United Kingdom)); Hawkesworth, M.R. (School of Physics and Space Research, University of Birmingham, Birmingham, B15 2TT (United Kingdom)); Beynon, T.D. (School of Physics and Space Research, University of Birmingham, Birmingham, B15 2TT (United Kingdom)); Green, S. (School of Physics and Space Research, University of Birmingham, Birmingham, B15 2TT (United Kingdom)); Rogers, J.D. (Rolls-Royce, Derby (United Kingdom)); Allen, M.J. (Rolls-Royce, Derby (United Kingdom)); Plummer, H.C. (Rolls-Royce, MatEval, Derby (United Kingdom)); Boulding, N.J. (Oxford Instruments (United Kingdom)); Cox, M. (Oxford Instruments (United Kingdom)); McDougall, I. (Oxford Instruments (United Kingdom))

    1994-12-30

    A thermal neutron radiography system based on a compact 12 MeV superconducting proton cyclotron is described. Neutrons are generated using a thick beryllium target and moderated in high density polyethylene. Monte Carlo computer simulations have been used to model the neutron and photon transport in order to optimise the performance of the system. With proton beam currents in excess of 100 [mu]A, it can provide high thermal neutron fluxes with L/D ratios of between 50 and 300 for various applications. Both film and electronic imaging are used to produce radiographs. The electronic imaging system consists of a [sup 6]Li-loaded ZnS intensifier screen, and a low light CCD or SIT camera. High resolution images can be recorded and computer-controlled data processing, analysis and display are possible. ((orig.))

  2. Beam tuning parameters for the Kolkata superconducting cyclotron

    International Nuclear Information System (INIS)

    Debnath, J.; Dey, M.K.; Paul, S.; Pradhan, J.; Bhunia, U.; Dutta, A.; Agrawal, A.; Naser, Md. Z.A.; Rashid, M.H.; Mallik, C.; Bhandari, R.K.

    2009-01-01

    The internal beam tuning in the Superconducting cyclotron at VECC will be started very soon. The magnetic field data has been used to explore the beam dynamical issues. There are two main coils and fourteen no. of trim coils. The optimised main coil and trim coil current settings for producing the required near-isochronous field fitting suitable phase-energy curve to accelerate different ion species in the operating region with minimum trim coil power as well as minimum error in the energy-phase curve have been calculated and reported here. The equilibrium orbit properties i.e., the radial and axial focusing frequencies, frequency error, integrated phase shift etc. have been studied. The important issues related to beam deliverables are explored. (author)

  3. A superconducting isochronous cyclotron stack as a driver for a thorium-cycle power reactor

    International Nuclear Information System (INIS)

    Kim, G.; May, D.; McIntyre, P.; Sattarov, A.

    2001-01-01

    Designs for thorium-cycle power reactors require a proton driver capable of 1 GeV energy and 10 MW total power. For this purpose we have prepared a preliminary design for the magnetic structure for a stack of 5 super-conducting isochronous cyclotrons, each delivering 2 MW beam power. By achieving the required power with multiple independent apertures rather than pushing beyond currently achieved limits, we hope to arrive at a design that is cost-minimum and reliable. Each sector magnet consists of a flux-coupled stack of cold-iron inserts supported within a single warm-iron, in a fashion inspired by the new Riken heavy-ion cyclotron. We have developed a preliminary field design in which in-plane fields are cancelled in all 5 apertures and the field-map is appropriate for the focusing optics of the sector cyclotron

  4. Electrical Insulation of 500-m High-Tc Superconducting Power Cable

    International Nuclear Information System (INIS)

    Takahashi, T; Ichikawa, M; Suzuki, H; Okamoto, T; Akita, S; Mukoyama, S; Yagi, M; Maruyama, S; Kimura, A

    2006-01-01

    Electrical insulation is one of the essential technologies for the electric power apparatus. Determination of testing voltages and design method of the electrical insulation layer are inextricably linked each other, and are critical to developing and realizing a cold dielectric (CD) type high-Tc superconducting (HTS) power cable. The authors had proposed the electrical insulation design method with concepts of partial discharge-free designs for ac voltage condition. This paper discusses the testing voltages for a 77 kV 1000 A HTS power cable with a length of 500 m, and describes results of various voltage withstand test. As a result, it is concluded that the proposed electrical insulation design method is appropriate for the HTS power cable

  5. Automated cyclotron tuning using beam phase measurements

    International Nuclear Information System (INIS)

    Timmer, J.H.; Roecken, H.; Stephani, T.; Baumgarten, C.; Geisler, A.

    2006-01-01

    The ACCEL K250 superconducting cyclotron is specifically designed for the use in proton therapy systems. The compact medical 250 MeV proton accelerator fulfils all present and future beam requirements for fast scanning treatment systems and is delivered as a turn key system; no operator is routinely required. During operation of the cyclotron heat dissipation of the RF system induces a small drift in iron temperature. This temperature drift slightly detunes the magnetic field and small corrections must be made. A non-destructive beam phase detector has been developed to measure and quantify the effect of a magnetic field drift. Signal calculations were made and the design of the capacitive pickup probe was optimised to cover the desired beam current range. Measurements showed a very good agreement with the calculated signals and beam phase can be measured with currents down to 3 nA. The measured phase values are used as input for a feedback loop controlling the current in the superconducting coil. The magnetic field of the cyclotron is tuned automatically and online to maintain a fixed beam phase. Extraction efficiency is thereby optimised continuously and activation of the cyclotron is minimised. The energy and position stability of the extracted beam are well within specification

  6. Medical Cyclotrons

    Science.gov (United States)

    Friesel, D. L.; Antaya, T. A.

    Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.

  7. Design of the proposed 250 MeV superconducting cyclotron magnet for proton therapy

    International Nuclear Information System (INIS)

    Dey, M.K.; Ahmed, M.; Murali, S.; Duttagupta, A.; Chaudhuri, J.; Mallik, C.; Bhandari, R.K.

    2006-01-01

    Here we describe the design calculations for the superconducting magnet of a 250 MeV proton cyclotron to be used for therapeutic purpose. Hard-edge approximation method has been adopted for finding the poletip geometry to meet the basic focusing requirements of the beam. Then the uniform-magnetization method has been applied to calculate the 3D magnetic field distribution due to saturated iron poletips, to verify the beam dynamical issues. (author)

  8. Epoxy resin casting of trim coils for superconducting cyclotron

    International Nuclear Information System (INIS)

    Hajra, D.P.; Sarkar, S.C.; Saha, Subimal; Chaudhuri, J.; Bhandari, R.K.

    2006-01-01

    The life of any magnet depends on the soundness of the coil insulation, its aging properties and initial and final endurance limitations. The insulation of water-cooled trim coils for superconducting cyclotron is made of glass fibre tape with heat cured unfilled epoxy resin combination. This type of insulation has been selected to achieve excellent stability against thermal and electromagnetic stresses, tight dimensional control, good dielectric strength, non-hygroscopic and considerably low vapour-pressure as it will be inside rough vacuum. The process development and the difficulties encountered for appropriate selection of epoxy resin combination, potting, vacuum process, curing cycle, control of coil dimension to achieve a sound coil absolutely free from cracks, trapped air and voids has been discussed. (author)

  9. Mechanical thermal and electric measurements on materials and components of the main coils of the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    Acerbi, E.; Rossi, L.

    1988-01-01

    The coils of the Milan Superconducting Cyclotron are the largest superconducting devices built up to now in Italy and constitute the first superconducting magnet for accelerator in Europe. Because of the large stored energy (more than 40 MJ), of the high stresses and of of the need of reliability, a lot of measurements were carried out as well on materials used for the coils, both on superconducting cable and structural materials, as on the main components of the coils and on two double pancakes prototypes (wound with full copper cable). In this paper the results on these measurements are reported and the results of tests on the prototypes are discussed. The aim is to provide an easy source of data for superconducting coils useful to verify calculations or to improve the performances

  10. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics.

    Science.gov (United States)

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Yasuda, Y; Morinobu, S; Tamii, A; Kamakura, K

    2014-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP.

  11. Design and investigations of the superconducting magnet system for the multipurpose superconducting electron cyclotron resonance ion source.

    Science.gov (United States)

    Tinschert, K; Lang, R; Mäder, J; Rossbach, J; Spädtke, P; Komorowski, P; Meyer-Reumers, M; Krischel, D; Fischer, B; Ciavola, G; Gammino, S; Celona, L

    2012-02-01

    The production of intense beams of heavy ions with electron cyclotron resonance ion sources (ECRIS) is an important request at many accelerators. According to the ECR condition and considering semi-empirical scaling laws, it is essential to increase the microwave frequency together with the magnetic flux density of the ECRIS magnet system. A useful frequency of 28 GHz, therefore, requires magnetic flux densities above 2.2 T implying the use of superconducting magnets. A cooperation of European institutions initiated a project to build a multipurpose superconducting ECRIS (MS-ECRIS) in order to achieve an increase of the performances in the order of a factor of ten. After a first design of the superconducting magnet system for the MS-ECRIS, the respective cold testing of the built magnet system reveals a lack of mechanical performance due to the strong interaction of the magnetic field of the three solenoids with the sextupole field and the magnetization of the magnetic iron collar. Comprehensive structural analysis, magnetic field calculations, and calculations of the force pattern confirm thereafter these strong interactions, especially of the iron collar with the solenoidal fields. The investigations on the structural analysis as well as suggestions for a possible mechanical design solution are given.

  12. submitter Development of a Superconducting Magnet for a Compact Cyclotron for Radioisotope Production

    CERN Document Server

    Garcia-Tabares, Luis; Calero, Jesus; Gutierrez, Jose L; Munilla, Javier; Obradors, Diego; Perez, Jose M; Toral, Fernando; Iturbe, Rafael; Minguez, Leire; Gomez, Jose; Rodilla, Elena; Bajko, Marta; Michels, Matthias; Berkowitz, Daniel; Haug, Friedrich

    2016-01-01

    The present paper describes the development process of a low critical temperature superconducting magnet to be installed in a compact cyclotron producing single-dose radioisotopes for clinical and preclinical applications. After a brief description of the accelerator, the magnet development process is described, starting from the magnetic, mechanical, quench, and thermal calculations, continuing with the designing process, particularly the support structure of the magnet and the cryogenic supply system, to finish with the fabrication and the first tests than have been performed.

  13. AGOR: A superconducting cyclotron for light and heavy ions plans for experimental facilities and physics program

    International Nuclear Information System (INIS)

    Gales, S.

    1991-01-01

    The construction of the K600 superconducting cyclotron AGOR, a joint undertaking of the KVI Groningen and the Institut de Physique Nucleaire at Orsay, has reached the stage where the assembly of major subsystems is underway. Field measurements are scheduled to start in the fall of this year, beam tests should start at Orsay by the end of 1992 before AGOR final installation at Groningen. The beam guiding system, the location and equipments of the main experimental areas are currently being designed. Taking advantage of the broad range of ions and energies that AGOR will made available (from 200 MeV protons to 100 MeV/A α down to 6 MeV/A Pb ions), the first ideas about the physics research to be done will be presented. (author) 28 refs., 15 figs., 2 tabs

  14. The preliminary tests of the superconducting electron cyclotron resonance ion source DECRIS-SC2.

    Science.gov (United States)

    Efremov, A; Bekhterev, V; Bogomolov, S; Drobin, V; Loginov, V; Lebedev, A; Yazvitsky, N; Yakovlev, B

    2012-02-01

    A new compact version of the "liquid He-free" superconducting ECR ion source, to be used as an injector of highly charged heavy ions for the MC-400 cyclotron, is designed and built at the Flerov Laboratory of Nuclear Reactions in collaboration with the Laboratory of High Energy Physics of JINR. The axial magnetic field of the source is created by the superconducting magnet and the NdFeB hexapole is used for the radial plasma confinement. The microwave frequency of 14 GHz is used for ECR plasma heating. During the first tests, the source shows a good enough performance for the production of medium charge state ions. In this paper, we will present the design parameters and the preliminary results with gaseous ions.

  15. More about a universal compact isochronous superconducting cyclotron archetype

    International Nuclear Information System (INIS)

    Laisne, A.

    1999-01-01

    Except the fact that they can accelerate protons at comparable energies, AGOR and CYCLONE 235 stand at two extremities as far as the complexity of the conceptual design is concerned. The widest range of ions species associated with a very large energy and RF frequency ranges for AGOR, a fixed energy and a constant RF frequency for only protons in CYCLONE 235. In fact, the two designs have in common the same theoretical 'model' that I described in a referred paper. Now, I suggest we look again at this model and try to show how it could be regarded as the 'Universal Compact Isochronous Superconducting Cyclotron Archetype'. Based on the behavior of CYCLONE 235, and on some more recent calculations, I will explain why the name of 'Archetype' can be used, and show how attractive is the simplicity of the ejection scheme ensued in terms of reliability and cost. (author)

  16. Intense highly charged ion beam production and operation with a superconducting electron cyclotron resonance ion source

    Science.gov (United States)

    Zhao, H. W.; Sun, L. T.; Guo, J. W.; Lu, W.; Xie, D. Z.; Hitz, D.; Zhang, X. Z.; Yang, Y.

    2017-09-01

    The superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is a superconducting-magnet-based electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged heavy ion beams. It is one of the best performing ECRISs worldwide and the first superconducting ECRIS built with an innovative magnet to generate a high strength minimum-B field for operation with heating microwaves up to 24-28 GHz. Since its commissioning in 2005, SECRAL has so far produced a good number of continuous wave intensity records of highly charged ion beams, in which recently the beam intensities of 40Ar+ and 129Xe26+ have, for the first time, exceeded 1 emA produced by an ion source. Routine operations commenced in 2007 with the Heavy Ion accelerator Research Facility in Lanzhou (HIRFL), China. Up to June 2017, SECRAL has been providing more than 28,000 hours of highly charged heavy ion beams to the accelerator demonstrating its great capability and reliability. The great achievement of SECRAL is accumulation of numerous technical advancements, such as an innovative magnetic system and an efficient double-frequency (24 +18 GHz ) heating with improved plasma stability. This article reviews the development of SECRAL and production of intense highly charged ion beams by SECRAL focusing on its unique magnet design, source commissioning, performance studies and enhancements, beam quality and long-term operation. SECRAL development and its performance studies representatively reflect the achievements and status of the present ECR ion source, as well as the ECRIS impacts on HIRFL.

  17. [Cyclotron based nuclear science

    International Nuclear Information System (INIS)

    1989-06-01

    This report contains papers on the following topics: Heavy ion reactors, nuclear structure and fundamental interactions; atomic and materials studies; nuclear theory; and superconducting cyclotron and instrumentation

  18. Superconducting magnet performance for 28 GHz electron cyclotron resonance ion source developed at the Korea Basic Science Institute.

    Science.gov (United States)

    Park, Jin Yong; Choi, Seyong; Lee, Byoung-Seob; Yoon, Jang-Hee; Ok, Jung-Woo; Kim, Byoung Chul; Shin, Chang Seouk; Ahn, Jung Keun; Won, Mi-Sook

    2014-02-01

    A superconducting magnet for use in an electron cyclotron resonance ion source was developed at the Korea Basic Science Institute. The superconducting magnet is comprised of three solenoids and a hexapole magnet. According to the design value, the solenoid magnets can generate a mirror field, resulting in axial magnetic fields of 3.6 T at the injection area and 2.2 T at the extraction region. A radial field strength of 2.1 T can also be achieved by hexapole magnet on the plasma chamber wall. NbTi superconducting wire was used in the winding process following appropriate techniques for magnet structure. The final assembly of the each magnet involved it being vertically inserted into the cryostat to cool down the temperature using liquid helium. The performance of each solenoid and hexapole magnet was separately verified experimentally. The construction of the superconducting coil, the entire magnet assembly for performance testing and experimental results are reported herein.

  19. Intense highly charged ion beam production and operation with a superconducting electron cyclotron resonance ion source

    Directory of Open Access Journals (Sweden)

    H. W. Zhao

    2017-09-01

    Full Text Available The superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL is a superconducting-magnet-based electron cyclotron resonance ion source (ECRIS for the production of intense highly charged heavy ion beams. It is one of the best performing ECRISs worldwide and the first superconducting ECRIS built with an innovative magnet to generate a high strength minimum-B field for operation with heating microwaves up to 24–28 GHz. Since its commissioning in 2005, SECRAL has so far produced a good number of continuous wave intensity records of highly charged ion beams, in which recently the beam intensities of ^{40}Ar^{12+} and ^{129}Xe^{26+} have, for the first time, exceeded 1 emA produced by an ion source. Routine operations commenced in 2007 with the Heavy Ion accelerator Research Facility in Lanzhou (HIRFL, China. Up to June 2017, SECRAL has been providing more than 28,000 hours of highly charged heavy ion beams to the accelerator demonstrating its great capability and reliability. The great achievement of SECRAL is accumulation of numerous technical advancements, such as an innovative magnetic system and an efficient double-frequency (24+18  GHz heating with improved plasma stability. This article reviews the development of SECRAL and production of intense highly charged ion beams by SECRAL focusing on its unique magnet design, source commissioning, performance studies and enhancements, beam quality and long-term operation. SECRAL development and its performance studies representatively reflect the achievements and status of the present ECR ion source, as well as the ECRIS impacts on HIRFL.

  20. Building on TR-24 success. Advanced Cyclotron Systems Inc. launches a new cyclotron model

    International Nuclear Information System (INIS)

    Russell Watt; William Gyles; Alexander Zyuzin

    2015-01-01

    ACSI is designing a new 30 MeV cyclotron based on the TR-24. While minimizing changes from the proven TR-24, including maintaining the same outer dimensions, the energy of the cyclotron will be increased to 30 MeV, which will make it the most compact, non-superconducting, 30 MeV cyclotron design to date. Maximum beam current will match the TR-24 at 1 mA. With the size and footprint of a typical low energy PET cyclotron, this system will offer users a cost effective solution for a diversified facility capable of producing a wide spectrum of PET and SPECT radioisotopes for research and commercial distribution. (author)

  1. Pantechnik new superconducting ion source: PantechniK Indian Superconducting Ion Source

    International Nuclear Information System (INIS)

    Gaubert, G.; Bieth, C.; Bougy, W.; Brionne, N.; Donzel, X.; Leroy, R.; Sineau, A.; Vallerand, C.; Villari, A. C. C.; Thuillier, T.

    2012-01-01

    The new ECR ion source PantechniK Indian Superconducting Ion Source (PKISIS) was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration, while the radial magnetic field is done with the multi-layer permanent magnets. Special care was devoted to the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using low temperature superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability and easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (T max = 1400 deg. C) installed with an angle of 5 deg. with respect to the source axis or a sputtering system, mounted on the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. The new source of Pantechnik is conceived for reaching optimum performances at 18 GHz RF frequencies. PKISIS magnetic fields are 2.1 T axial B inj and 1.32 T radial field in the wall, variable B min with an independent coil and a large and opened extraction region. Moreover, PKISIS integrates modern design concepts, like RF direct injection (2 kW availability), dc-bias moving disk, out-of-axis oven and axial sputtering facility for metal beams. Finally, PKISIS is also conceived in order to operate in a high-voltage platform with minor power consumption.

  2. Cyclotron based nuclear science. Progress report, April 1, 1985-March 31, 1986

    International Nuclear Information System (INIS)

    Youngblood, D.H.

    1986-08-01

    Progress report for cyclotron based nuclear science cyclotron facility are summarized. Research is described under the headings heavy ion reactions, nuclear theory, atomic studies and activation analysis, superconducting cyclotron and instrumentation. Publications are listed

  3. Digital Data Acquisition System for experiments with segmented detectors at National Superconducting Cyclotron Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Starosta, K., E-mail: starosta@sfu.c [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Vaman, C.; Miller, D.; Voss, P.; Bazin, D.; Glasmacher, T. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Crawford, H.; Mantica, P. [National Superconducting Cyclotron Laboratory and Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Tan, H.; Hennig, W.; Walby, M.; Fallu-Labruyere, A.; Harris, J.; Breus, D.; Grudberg, P.; Warburton, W.K. [XIA LLC, Hayward, CA 94544 (United States)

    2009-11-11

    A 624-channel Digital Data Acquisition System capable of instrumenting the Segmented Germanium Array at National Superconducting Cyclotron Laboratory has been implemented using Pixie-16 Digital Gamma Finder modules by XIA LLC. The system opens an opportunity for determination of the first interaction position of a gamma ray in a SeGA detector from implementation of gamma-ray tracking. This will translate into a significantly improved determination of angle of emission, and in consequence much better Doppler corrections for experiments with fast beams. For stopped-beam experiments the system provides means for zero dead time measurements of rare decays, which occur on time scales of microseconds.

  4. Digital Data Acquisition System for experiments with segmented detectors at National Superconducting Cyclotron Laboratory

    International Nuclear Information System (INIS)

    Starosta, K.; Vaman, C.; Miller, D.; Voss, P.; Bazin, D.; Glasmacher, T.; Crawford, H.; Mantica, P.; Tan, H.; Hennig, W.; Walby, M.; Fallu-Labruyere, A.; Harris, J.; Breus, D.; Grudberg, P.; Warburton, W.K.

    2009-01-01

    A 624-channel Digital Data Acquisition System capable of instrumenting the Segmented Germanium Array at National Superconducting Cyclotron Laboratory has been implemented using Pixie-16 Digital Gamma Finder modules by XIA LLC. The system opens an opportunity for determination of the first interaction position of a γ ray in a SeGA detector from implementation of γ-ray tracking. This will translate into a significantly improved determination of angle of emission, and in consequence much better Doppler corrections for experiments with fast beams. For stopped-beam experiments the system provides means for zero dead time measurements of rare decays, which occur on time scales of microseconds.

  5. Digital Data Acquisition System for experiments with segmented detectors at National Superconducting Cyclotron Laboratory

    Science.gov (United States)

    Starosta, K.; Vaman, C.; Miller, D.; Voss, P.; Bazin, D.; Glasmacher, T.; Crawford, H.; Mantica, P.; Tan, H.; Hennig, W.; Walby, M.; Fallu-Labruyere, A.; Harris, J.; Breus, D.; Grudberg, P.; Warburton, W. K.

    2009-11-01

    A 624-channel Digital Data Acquisition System capable of instrumenting the Segmented Germanium Array at National Superconducting Cyclotron Laboratory has been implemented using Pixie-16 Digital Gamma Finder modules by XIA LLC. The system opens an opportunity for determination of the first interaction position of a γ ray in a SeGA detector from implementation of γ-ray tracking. This will translate into a significantly improved determination of angle of emission, and in consequence much better Doppler corrections for experiments with fast beams. For stopped-beam experiments the system provides means for zero dead time measurements of rare decays, which occur on time scales of microseconds.

  6. Emittance study of a 28 GHz electron cyclotron resonance ion source for the Rare Isotope Science Project superconducting linear accelerator.

    Science.gov (United States)

    Park, Bum-Sik; Hong, In-Seok; Jang, Ji-Ho; Jin, Hyunchang; Choi, Sukjin; Kim, Yonghwan

    2016-02-01

    A 28 GHz electron cyclotron resonance (ECR) ion source is being developed for use as an injector for the superconducting linear accelerator of the Rare Isotope Science Project. Beam extraction from the ECR ion source has been simulated using the KOBRA3-INP software. The simulation software can calculate charged particle trajectories in three dimensional complex magnetic field structures, which in this case are formed by the arrangement of five superconducting magnets. In this study, the beam emittance is simulated to understand the effects of plasma potential, mass-to-charge ratio, and spatial distribution. The results of these simulations and their comparison to experimental results are presented in this paper.

  7. A search for superconductivity below 1 K in transition metal borides

    International Nuclear Information System (INIS)

    Leyarovska, L.; Leyarovski, E.

    1979-01-01

    Some AlB 2 -type (C32 structure) boron compounds were examined for superconductivity down to 0.42 K; the compounds have the formula MeB 2 (Me equivalent to Ti, Zr, Hf, V, Nb, Ta, Cr, Mo) (the atomic ratio of metal to boron was 0.5). Only NbB 2 was found to be superconducting with Tsub(c) = 0.62 K and a surprisingly high value of Hsub(c)(0), about 1600 Oe. Other transition metal as well as non-transition metal boron phases were also tested for superconductivity down to 0.42 K; these compounds were MeB 2 (Me equivalent to Ca, Sr, Ba), W 2 B 5 , CrB, Cr 5 B 3 , UB 2 , UB 4 and UB 12 . None of these compounds proved to be superconducting above 0.42 K; nor was any trace of superconductivity down to 0.42 K observed in MoB and NbB. (Auth.)

  8. First Results of the IOT Based 300 kW 500 MHz Amplifier for the Diamond Light Source

    CERN Document Server

    Jensen, Morten; Maddock, Matt; Müller, Marc; Rains, Simon; Watkins, Alun V

    2005-01-01

    We present the first RF measurements of the IOT based 300 kW 500 MHz amplifier for the Diamond Light Source. Four 80 kW IOTs are combined using a waveguide combiner to achieve the RF requirement of up to 300 kW for each of three superconducting cavities for the main storage ring. The IOTs are protected by a full power circulator and a 300 kW ferrite RF load. This is the first time IOTs will be used for a synchrotron light source. This paper gives an overview of the design of the Thales amplifiers and IOTs with commissioning results including measurements of key components and overall RF performance following factory tests and the installation of the first unit

  9. Injection and extraction for cyclotrons

    International Nuclear Information System (INIS)

    Heikkinen, P.

    1994-01-01

    External ion sources for cyclotrons are needed for polarised and heavy ions. This calls for injection systems, either radial or axial. Radial injection is also needed when a cyclotron works as a booster after another cyclotron or a linear accelerator (usually tandem). Requirements for injection differ from separated sector cyclotrons where there is plenty of room to house inflectors and/or strippers, to superconducting cyclotrons where the space is limited by a small magnet gap, and high magnetic field puts other limitations to the inflectors. Several extraction schemes are used in cyclotrons. Stripping injection is used for H - and also for heavy ions where the q/m ratio is usually doubled. For other cases, electric and magnetic deflection has to be used. To increase the turn separation before the first deflector, both resonant and non-resonant schemes are used. In this lecture, external injection systems are surveyed and some rules to thumb for injection parameters are given. Extraction schemes are also reviewed. (orig.)

  10. Magnetic field related mechanical tolerances for the proposed Chalk River superconducting heavy-ion cyclotron

    International Nuclear Information System (INIS)

    Heighway, E.A.; Chaplin, K.R.

    1977-11-01

    A four sector azimuthally varying field cyclotron with superconducting main coils has been proposed as a heavy-ion post-accelerator for the Chalk River MP Tandem van de Graaff. The radial profile of the average axial field will be variable using movable steel trim rods. The field errors due to coil, trim rod and flutter pole imperfections are calculated. Those considered are errors in the axial field, first and second azimuthal harmonic axial fields, transverse field and first azimuthal harmonic transverse field. Such fields induce phase slip, axial or radial coherent oscillations and can result in axial or radial beam instability. The allowed imperfections (tolerances) required to retain stability and maintain acceptably small coherent oscillation amplitudes are calculated. (author)

  11. Nb3Sn superconducting magnets for electron cyclotron resonance ion sources.

    Science.gov (United States)

    Ferracin, P; Caspi, S; Felice, H; Leitner, D; Lyneis, C M; Prestemon, S; Sabbi, G L; Todd, D S

    2010-02-01

    Electron cyclotron resonance (ECR) ion sources are an essential component of heavy-ion accelerators. Over the past few decades advances in magnet technology and an improved understanding of the ECR ion source plasma physics have led to remarkable performance improvements of ECR ion sources. Currently third generation high field superconducting ECR ion sources operating at frequencies around 28 GHz are the state of the art ion injectors and several devices are either under commissioning or under design around the world. At the same time, the demand for increased intensities of highly charged heavy ions continues to grow, which makes the development of even higher performance ECR ion sources a necessity. To extend ECR ion sources to frequencies well above 28 GHz, new magnet technology will be needed in order to operate at higher field and force levels. The superconducting magnet program at LBNL has been developing high field superconducting magnets for particle accelerators based on Nb(3)Sn superconducting technology for several years. At the moment, Nb(3)Sn is the only practical conductor capable of operating at the 15 T field level in the relevant configurations. Recent design studies have been focused on the possibility of using Nb(3)Sn in the next generation of ECR ion sources. In the past, LBNL has worked on the VENUS ECR, a 28 GHz source with solenoids and a sextupole made with NbTi operating at fields of 6-7 T. VENUS has now been operating since 2004. We present in this paper the design of a Nb(3)Sn ECR ion source optimized to operate at an rf frequency of 56 GHz with conductor peak fields of 13-15 T. Because of the brittleness and strain sensitivity of Nb(3)Sn, particular care is required in the design of the magnet support structure, which must be capable of providing support to the coils without overstressing the conductor. In this paper, we present the main features of the support structure, featuring an external aluminum shell pretensioned with water

  12. Beam-chopping system for LNS superconducting cyclotron

    International Nuclear Information System (INIS)

    Calabretta, L.; Caruso, A.; Raia, G.; Sparta, A.; Zappala, E.; Zingale, A.; Khemka, P.; Wei, C.Y.

    1999-01-01

    Several experiments which foresee the measurement of time of flight require a bunched beam with a FWHM smaller that 1 ns and a temporal separation from 100 to 200 ns. An H.E. Chopper that achieves this temporal separation between the impulses has been installed along the beam extraction line of the cyclotron. The two electrodes, which deflect the beam and the inductance coil are both under vacuum. The operating frequency range of the LC resonant circuit is from 4.5 to 9 MHz and the maximum design voltage is 70 kV. The chopper selects only the beam bunches which cross the device at peak voltage, one bunch for cycle. A steerer magnet to recover the selected bunches on the beam axis is used. All the tests, measurements and chopper's performance, will be presented. (authors)

  13. Beam-chopping system for LNS superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Calabretta, L.; Caruso, A.; Raia, G.; Sparta, A.; Zappala, E.; Zingale, A. [INFN-LNS, Catania (Italy); Khemka, P. [VEEC, Calcutta (India); Wei, C.Y. [Institute of Modern Physics, Lanzhou (China)

    1999-07-01

    Several experiments which foresee the measurement of time of flight require a bunched beam with a FWHM smaller that 1 ns and a temporal separation from 100 to 200 ns. An H.E. Chopper that achieves this temporal separation between the impulses has been installed along the beam extraction line of the cyclotron. The two electrodes, which deflect the beam and the inductance coil are both under vacuum. The operating frequency range of the LC resonant circuit is from 4.5 to 9 MHz and the maximum design voltage is 70 kV. The chopper selects only the beam bunches which cross the device at peak voltage, one bunch for cycle. A steerer magnet to recover the selected bunches on the beam axis is used. All the tests, measurements and chopper's performance, will be presented. (authors)

  14. Cyclotron based nuclear science: Progress report, April 1, 1986-March 31, 1987

    International Nuclear Information System (INIS)

    1987-08-01

    This report contains descriptions of research programs at the Institute, progress on construction of the K500 cyclotron, and descriptions of new experimental devices being built to take advantage of new beams that will be available. Several milestones were reached in construction of the new cyclotron during the period. In early summer, 1986, the magnet was completed with all trim coils and shimming iron in place. During July and August, the final field maps were made, which will be used for calculations of run parameters. In the spring, one rf amplifier was completed and tested over the full frequency and power range. Also in the spring, the computer control system successfully operated positioning controls and trim coil power supplies. Final assembly of the rf system including the dees, resonators and other 2 rf amplifiers is now underway. Initial attempts at getting beam are expected in September. The design of the ECR source was completed in the fall. A beam line configuration has been designed for the K500 cyclotron which will result initially in 3 lines, with a fourth to be added in 1988. With the eminent completion of the K500, there has been considerable instrumentation development. A 4π neutron calorimeter is under construction for heavy ion reaction studies, construction is beginning on a proton spectrometer for studies of Gamow-Teller matrix elements with the (d, 2 He) reaction, and several detector systems are being developed. During the year, the 88 inch cyclotron operated 4845 hours for research and beam development. Research programs in nuclear science scheduled 57% of the time. Atomic physics programs used 19% of the time, and a program in trace analysis scheduled 6%. An industrial testing laboratory used 18 hours. The remainder of the time was used for beam development, primarily for increasing the energy and/or intensity of heavy ion beams

  15. Superconductivity in Medicine

    Science.gov (United States)

    Alonso, Jose R.; Antaya, Timothy A.

    2012-01-01

    Superconductivity is playing an increasingly important role in advanced medical technologies. Compact superconducting cyclotrons are emerging as powerful tools for external beam therapy with protons and carbon ions, and offer advantages of cost and size reduction in isotope production as well. Superconducting magnets in isocentric gantries reduce their size and weight to practical proportions. In diagnostic imaging, superconducting magnets have been crucial for the successful clinical implementation of magnetic resonance imaging. This article introduces each of those areas and describes the role which superconductivity is playing in them.

  16. Heavy-ion injector based on an electron cyclotron ion source for the superconducting linear accelerator of the Rare Isotope Science Project.

    Science.gov (United States)

    Hong, In-Seok; Kim, Yong-Hwan; Choi, Bong-Hyuk; Choi, Suk-Jin; Park, Bum-Sik; Jin, Hyun-Chang; Kim, Hye-Jin; Heo, Jeong-Il; Kim, Deok-Min; Jang, Ji-Ho

    2016-02-01

    The injector for the main driver linear accelerator of the Rare Isotope Science Project in Korea, has been developed to allow heavy ions up to uranium to be delivered to the inflight fragmentation system. The critical components of the injector are the superconducting electron cyclotron resonance (ECR) ion sources, the radio frequency quadrupole (RFQ), and matching systems for low and medium energy beams. We have built superconducting magnets for the ECR ion source, and a prototype with one segment of the RFQ structure, with the aim of developing a design that can satisfy our specifications, demonstrate stable operation, and prove results to compare the design simulation.

  17. RF tuning system for superconducting cyclotron at VECC

    International Nuclear Information System (INIS)

    Mandal, Aditya; Som, S.; Pal, Saikat; Seth, S.; Mukherjee, A.K.; Gangopadhyay, P.; Prasad, J.S.; Raj, P.R.; Manna, S.K.; Banerjee, M.; Krishnaiah, K.V.; Maskawade, S.; Saha, M.S.; Biswas, S.; Panda, Umashakar

    2009-01-01

    The RF system of Superconducting cyclotron at VECC has operational frequency 9-27 MHz. It has three numbers of tunable rf amplifier cavities as well as six numbers of tunable Main resonant cavities. RF tuning system takes care of movement of nine stepper motor based sliding short movement and hydraulic driven three coupling capacitors and three trimmer capacitors. The PC-based stepper motor controlled sliding short movement system has positional accuracy of around 20 micron and PC-based hydraulically driven couplers and trimmers system has 10 micron positional accuracy. The RF power is capacitively coupled to the dee (accelerating electrode) of the main resonant cavity through Coupler (Coupling capacitor). The coupling capacitor is used to match the impedance of the main resonant cavity to the 50 Ohm output impedance of final RF power amplifier. Trimmer capacitor operates in closed loop for the adjustment of cavity phase variation arising due to temperature variation and beam loading of the cavity. Coupler can travel 100 mm. and trimmer has 20 mm. travels. A PLC based PID control system has been developed for positional control of the coupler and trimmer. One position control mode of trimmer is same as coupling capacitor and another is velocity control mode. Velocity control mode operates in close-loop. The positional data of different frequencies of nine stepper motors and three coupling capacitors are stored in a database. (author)

  18. Optimization of the shape of the HV electrode of the electrostatic deflectors for the Milan superconducting cyclotron

    International Nuclear Information System (INIS)

    De Martinis, C.; Ferrari, A.

    1987-01-01

    The electrostatic deflectors for the extraction of the beam from the Milan Superconducting Cyclotron are presently under development. The early tests showed that major troubles arise from the modifications induced in the discharge mechanism by the presence of the magnetic field, resulting in a drastic reduction of the deflector performances. Therefore a detailed analysis of the electric field configuration of the deflector has been carried out in order to improve its performances. In this paper the results so far obtained in the optimization of the shape of the electrode and insulator fixing are reported

  19. Recent results on electron cyclotron current drive and MHD activity in RTP

    NARCIS (Netherlands)

    Donne, A.J.H.; Schuller, F.C.; Oomens, A.A.M.; de Baar, M.R.; Barth, C.J.; Beurskens, M.N.A.; Box, F.M.A.; van Gelder, J.F.M.; Grobben, B.J.J.; Groot, de B.; Herranz, J.M.; Hogeweij, G.M.D.; Hokin, S.A.; Howard, J.; Hugenholtz, C.A.J.; Karelse, F.A.; de Kloe, J.; Kruijt, O.G.; Kuyvenhoven, S.; Lok, J.; Cardozo, N.J.L.; van der Meiden, H.J.; Meijer, F.G.; Montvai, A.; Oyevaar, T.; Pijper, F.J.; Polman, R.W.; Rommers, J.H.; Salzedas, F.; Schokker, B.C.; Smeets, P.H.M.; Tanzi, C.P.; Tito, C.J.; Verhaag, G.C.H.M.; Westerhof, E.

    1997-01-01

    The RTP tokamak (R = 0.72 m, a = 0.164 m, B-phi < 2 5.T, I-p = < 150 kA) is equipped with three gyrotrons (2 x 60 GHz, 180 kW, 100 ms each; 1 x 110 GHz, 500 kW, 200 ms) for electron cyclotron heating (ECH) and current drive (ECCD). The power from one of the 60 GHz gyrotrons is launched via an

  20. The beam commissioning of BRIF and future cyclotron development at CIAE

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tianjue, E-mail: tjzhang@ciae.ac.cn; Yang, Jianjun, E-mail: yangjianjun2000@tsinghua.org.cn

    2016-06-01

    As an upgrade project of the existing HI-13 tandem accelerator facility, the Beijing Radioactive Ion-beam Facility (BRIF) is being constructed in China Institute of Atomic Energy (CIAE). This project consists of an 100 MeV proton compact cyclotron, a two-stage ISOL system, a superconducting linac booster and various experimental terminals. The beam commissioning of the cyclotron was launched by the end of 2013 and on July 4, 2014 the first 100 MeV proton beam was received on a temporary target which was positioned at the outlet of the cyclotron. The beam current was stably maintained at above 25 μA for about 9 h on July 25, 2014 and the cyclotron is now ready for providing CW proton beam on target-source for RIB production. The beam current is expected to be increased to 200–500 μA in the coming years. The installation of the ISOL system is finished and the stable ion beam test shows it can reach a mass resolution better than 10,000. It is expected to generate dozens of RIB by 100 MeV proton beam. In addition, this paper also introduces the recent progress of the pre-study of an 800 MeV, 3–4 MW separate-sector proton cyclotron, which is aimed to provide high power proton beam for various applications, such as neutron and neutrino physics, proton radiography and nuclear data measurement and ADS system.

  1. Ac loss measurements on a superconducting transformer for a 25 kA superconducting rectifier

    NARCIS (Netherlands)

    ten Kate, Herman H.J.; Mulders, J.M.; de Reuver, J.L.; van de Klundert, L.J.M.

    1984-01-01

    Ac loss measurements have been performed on a superconducting transformer. The transformer is a part of a 25 kA thermally switched superconducting rectifier operating at a frequency of 0.1 Hz. The loss measurements have been automatized by means of a microcomputer sampling four relevant signals and

  2. Radioisotope production with a medical cyclotron

    International Nuclear Information System (INIS)

    Silvester, D.J.

    1974-01-01

    The cyclotron of Hammersmith hospital in England was completed and started the operation in 1955. The feature is in its design operable at high beam current, reaching 500μA in internal beam and 300μA in external beam. In 1960's, twelve nuclides of radioactive pharmaceuticals were produced with the cyclotron. C-11, N-13 and O-15 have been used in the form of radioactive gases such as CO or H 2 O to test lung functions. F-18 has been used for bone scanning. K-43 is employed in the research of electrolyte balancing together with Na-24 and Br-77. Fe-52 is utilized in iron ion researches as a tracer. Cs-129 is highly evaluated as an isotope for imaging cardiac clogging part. Radioisotopes must be much more used in the examination of in vivo metabolic function. For this purpose, peculiarly labelled compounds should be further developed. It is welcome that the persons paying attention to the medical prospect of cyclotrons are increasing. The author hopes to continue his endeavour to find new products made with the cyclotron for human welfare. (Wakatsuki, Y.)

  3. Conventional superconductivity at 203 K at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Drozdov, Alexander; Eremets, Mikhail; Troyan, Ivan [Max-Planck-Institut fuer Chemie, Hahn-Meitner-Weg 1, 55128 Mainz (Germany); Ksenofontov, Vadim; Shylin, Sergii [Institut fuer Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Universitet Mainz, Staudingerweg 9, 55099 Mainz (Germany)

    2016-07-01

    A search for high, room temperature conventional superconductivity is promising as the Bardeen-Cooper-Schrieffer (BCS) theory in the Eliashberg formulation puts no apparent limits on T{sub c}. Materials with light elements are especially favorable as they provide high frequencies in the phonon spectrum. However only a moderately high T{sub c} = 39 K has been found in this search in MgB{sub 2}. We systematically studied metallic hydrogen and covalent hydrogen dominant compounds and found the record T{sub c} of 203 K at pressure 140 GPa in sulfur hydride. We proved occurrence of superconductivity by the sharp drop of the resistivity to zero; the decrease of T{sub c} with magnetic field; the pronounce isotope shift of T{sub c} in D{sub 2}S which evidences of a major role of phonons in the superconductivity; and the magnetic susceptibility measurements. The X-ray diffraction data confirmed that the superconductive phase has the predicted bcc structure. This phase can be considered as an atomic hydrogen superconductor stabilized by sulfur.

  4. Intense beam production of highly charged heavy ions by the superconducting electron cyclotron resonance ion source SECRAL.

    Science.gov (United States)

    Zhao, H W; Sun, L T; Zhang, X Z; Guo, X H; Cao, Y; Lu, W; Zhang, Z M; Yuan, P; Song, M T; Zhao, H Y; Jin, T; Shang, Y; Zhan, W L; Wei, B W; Xie, D Z

    2008-02-01

    There has been increasing demand to provide higher beam intensity and high enough beam energy for heavy ion accelerator and some other applications, which has driven electron cyclotron resonance (ECR) ion source to produce higher charge state ions with higher beam intensity. One of development trends for highly charged ECR ion source is to build new generation ECR sources by utilization of superconducting magnet technology. SECRAL (superconducting ECR ion source with advanced design in Lanzhou) was successfully built to produce intense beams of highly charged ion for Heavy Ion Research Facility in Lanzhou (HIRFL). The ion source has been optimized to be operated at 28 GHz for its maximum performance. The superconducting magnet confinement configuration of the ion source consists of three axial solenoid coils and six sextupole coils with a cold iron structure as field booster and clamping. An innovative design of SECRAL is that the three axial solenoid coils are located inside of the sextupole bore in order to reduce the interaction forces between the sextupole coils and the solenoid coils. For 28 GHz operation, the magnet assembly can produce peak mirror fields on axis of 3.6 T at injection, 2.2 T at extraction, and a radial sextupole field of 2.0 T at plasma chamber wall. During the commissioning phase at 18 GHz with a stainless steel chamber, tests with various gases and some metals have been conducted with microwave power less than 3.5 kW by two 18 GHz rf generators. It demonstrates the performance is very promising. Some record ion beam intensities have been produced, for instance, 810 e microA of O(7+), 505 e microA of Xe(20+), 306 e microA of Xe(27+), and so on. The effect of the magnetic field configuration on the ion source performance has been studied experimentally. SECRAL has been put into operation to provide highly charged ion beams for HIRFL facility since May 2007.

  5. First two operational years of the electron-beam ion trap charge breeder at the National Superconducting Cyclotron Laboratory

    Directory of Open Access Journals (Sweden)

    A. Lapierre

    2018-05-01

    Full Text Available The electron-beam ion trap (EBIT charge breeder of the ReA post-accelerator, located at the National Superconducting Cyclotron Laboratory (Michigan State University, started on-line operation in September 2015. Since then, the EBIT has delivered many pilot beams of stable isotopes and several rare-isotope beams. An operating aspect of the ReA EBIT is the breeding of high charge states to reach high reaccelerated beam energies. Efficiencies in single charge states of more than 20% were measured with ^{39}K^{15+}, ^{85}Rb^{27+}, ^{47}K^{17+}, and ^{34}Ar^{15+}. Producing high charge states demands long breeding times. This reduces the ejection frequency and, hence, increases the number of ions ejected per pulse. Another operating aspect is the ability to spread the distribution in time of the ejected ion pulses to lower the instantaneous rate delivered to experiments. Pulse widths were stretched from a natural 25  μs up to ∼70  ms. This publication reviews the progress of the ReA EBIT system over the years and presents the results of charge-breeding efficiency measurements and pulse-stretching tests obtained with stable- and rare-isotope beams. Studies performed with high sensitivity to identify and quantify stable-isotope contaminants from the EBIT are also presented, along with a novel method for purifying beams.

  6. Measuring the microwave response of superconducting Nb:STO and Ti at mK temperatures using superconducting resonators

    Energy Technology Data Exchange (ETDEWEB)

    Thiemann, Markus; Beutel, Manfred; Dressel, Martin; Scheffler, Marc [1. Physikalisches Institut, Universitaet Stuttgart (Germany); Fillis-Tsirakis, Evangelos; Boschker, Hans; Mannhart, Jochen [Max Planck Institute for Solid State Research, Stuttgart (Germany)

    2016-07-01

    Niobium doped SrTiO{sub 3} is a superconductor, with the lowest charge carrier density among all superconductors. It shows a dome in the transition temperature as a function of doping concentration with a maximum T{sub c} ∼ 0.3 K. The superconducting dome may originate from the different bands being occupied depending on the doping level. The low energy scales of the system, as indicated by the low T{sub c} are within the GHz-regime. Therefore microwave measurements are a powerful technique to reveal the electronic properties of these superconductors. We preformed microwave measurements on Nb:STO of different doping levels in a dilution refrigerator, using superconducting stripline resonators. Measurements were done in a temperature and frequency range from 40-400 mK and 1-20 GHz, covering the normal and superconducting states. For comparison we also measured the temperature dependence of the surface impedance of superconducting titanium (T{sub c} ∼ 0.5 K), which can be well described by the Mattis-Bardeen equations with a ratio (2Δ)/(k{sub B}T{sub c}) = 3.56. Therefore titanium is an ideal reference sample representing a conventional BCS-superconductor.

  7. A thermally switched 9 kA superconducting rectifier fluxpump

    NARCIS (Netherlands)

    ten Kate, Herman H.J.; Bunk, Paul B.; Steffens, Harry A.; van de Klundert, Louis J.M.

    1981-01-01

    The feasibility of superconducting rectifier-fluxpumps has to be demonstrated at current levels of 10 - 100 kA, where is asked for in the superconducting devices now being planned. An intensive program has been started at the low temperature division of the University of Twente to construct such

  8. Progress report: Variable Energy Cyclotron Centre, Calcutta

    International Nuclear Information System (INIS)

    1999-01-01

    This volume of the progress report brings out the scientific and technical activities of Variable Energy Cyclotron Centre, Calcutta during the year 1999. This includes brief review of the various R and D activities of the Centre and outside users of the cyclotron from the universities and other research institutes. The operational activities of the cyclotron with ECR ion sources, accelerator oriented research activities, activities on detector, target and electronics are reported. The activities of the Computer and Informatics group are described. The status report of the ongoing projects is also provided. The main activities of the superconducting cyclotron project, radioactive ion beam project, heavy ion experimental facility, advanced computational facility, recovery and analysis of helium from hot springs and material science research are described

  9. Superconductivity at 43K in SmFeAsO1-xFx

    Science.gov (United States)

    Chen, X. H.; Wu, T.; Wu, G.; Liu, R. H.; Chen, H.; Fang, D. F.

    2008-06-01

    Since the discovery of high-transition-temperature (high-Tc) superconductivity in layered copper oxides, extensive effort has been devoted to exploring the origins of this phenomenon. A Tc higher than 40K (about the theoretical maximum predicted from Bardeen-Cooper-Schrieffer theory), however, has been obtained only in the copper oxide superconductors. The highest reported value for non-copper-oxide bulk superconductivity is Tc = 39K in MgB2 (ref. 2). The layered rare-earth metal oxypnictides LnOFeAs (where Ln is La-Nd, Sm and Gd) are now attracting attention following the discovery of superconductivity at 26K in the iron-based LaO1-xFxFeAs (ref. 3). Here we report the discovery of bulk superconductivity in the related compound SmFeAsO1-xFx, which has a ZrCuSiAs-type structure. Resistivity and magnetization measurements reveal a transition temperature as high as 43K. This provides a new material base for studying the origin of high-temperature superconductivity.

  10. Manufacturing of a superconducting magnet system for 28 GHz electron cyclotron resonance ion source at KBSI.

    Science.gov (United States)

    Lee, B S; Choi, S; Yoon, J H; Park, J Y; Won, M S

    2012-02-01

    A magnet system for a 28 GHz electron cyclotron resonance ion source is being developed by the Korea Basic Science Institute. The configuration of the magnet system consists of 3 solenoid coils for a mirror magnetic field and 6 racetrack coils for a hexapole magnetic field. They can generate axial magnetic fields of 3.6 T at the beam injection part and 2.2 T at the extraction part. A radial magnetic field of 2.1 T is achievable at the plasma chamber wall. A step type winding process was employed in fabricating the hexapole coil. The winding technique was confirmed through repeated cooling tests. Superconducting magnets and a cryostat system are currently being manufactured.

  11. Demonstration of the 500 kW stoker burning system; 500 kW stokeripolttojaerjestelmaen demonstrointi

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H. [VTT Energy, Jyvaeskylae (Finland); Kantalainen, K. [Hoegfors Laempoe Oy, Saarijaervi (Finland)

    1995-12-31

    The objective of the project is to demonstrate the operation of a 500 kW stoker-burning system in practice. The project is continuation of the previous projects of the Bioenergy research programme, 303 - Development of automatic heating system for wood chips and sod peat, carried out by VTT Energy, and Y301 - Development of heating boiler for wood chips and sod peat, carried out by Hoegfors Laempoe Oy. A 500 kW (nominal power) stoker-burner was constructed on the basis of the results of these projects. The burner was mounted on ETNA 500 bioenergy boiler. Screw-feeders, constructed by Maamiehen Saehkoe Oy, were used as fuel feeding system. Maamiehen Saehkoe Oy delivered also the automation system for the combustion equipment. Combustion air pre-heater was mounted on the boiler for promotion of the combustion of moist fuel. Testing of the equipment was carried out at the laboratory of VTT Energy in Jyvaeskylae in October-November 1994. In December 1994 the equipment was transported to Jalasjaervi, to heating station of the farmer Juha Jyrae. The actual heat generation started in the beginning of February 1995, when the greenhouses started to require heating. Sod peat has been used as the fuel. VTT Energy has carried out the efficiency and emission measurements in the heating station with sod peat in March 1995, and with reed canary grass in autumn 1995. The energy generation and fuel consumption have been followed all the time

  12. Demonstration of the 500 kW stoker burning system; 500 kW stokeripolttojaerjestelmaen demonstrointi

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H [VTT Energy, Jyvaeskylae (Finland); Kantalainen, K [Hoegfors Laempoe Oy, Saarijaervi (Finland)

    1996-12-31

    The objective of the project is to demonstrate the operation of a 500 kW stoker-burning system in practice. The project is continuation of the previous projects of the Bioenergy research programme, 303 - Development of automatic heating system for wood chips and sod peat, carried out by VTT Energy, and Y301 - Development of heating boiler for wood chips and sod peat, carried out by Hoegfors Laempoe Oy. A 500 kW (nominal power) stoker-burner was constructed on the basis of the results of these projects. The burner was mounted on ETNA 500 bioenergy boiler. Screw-feeders, constructed by Maamiehen Saehkoe Oy, were used as fuel feeding system. Maamiehen Saehkoe Oy delivered also the automation system for the combustion equipment. Combustion air pre-heater was mounted on the boiler for promotion of the combustion of moist fuel. Testing of the equipment was carried out at the laboratory of VTT Energy in Jyvaeskylae in October-November 1994. In December 1994 the equipment was transported to Jalasjaervi, to heating station of the farmer Juha Jyrae. The actual heat generation started in the beginning of February 1995, when the greenhouses started to require heating. Sod peat has been used as the fuel. VTT Energy has carried out the efficiency and emission measurements in the heating station with sod peat in March 1995, and with reed canary grass in autumn 1995. The energy generation and fuel consumption have been followed all the time

  13. Magnetic study of extraction elements of compact cyclotron beam with AGOR superconducting coils

    International Nuclear Information System (INIS)

    Gustafsson, S.

    1991-12-01

    The extraction system of the superconducting cyclotrons is normally making a large use of electric extractors followed by magnetostatic elements. The electric field limit initially hoped for (14 MV/m) has been shown to be too optimistic. A more realistic value is around 10 MV/m in the concerned geometries. The first element of the AGOR extraction system is an electrostatic channel where the maximum electric field is limited to 10.5 MV/m. The smaller separation between the internal beam and the extracted beam at the entrance of the first magnetic element is compensated by the replacement of the usual magnetostatic channels with high power electromagnetic channels placed in the reduced space close to the internal beam and where the horizontal position can be adjusted according to the kind of ion accelerated and its energy. The fringing field very close to the channels is controlled with the help of correction coils reducing the perturbations of the internal beam trajectories to an acceptable level

  14. Compact superconducting 250 MeV proton cyclotron for the PSI PROSCAN proton therapy project

    International Nuclear Information System (INIS)

    Schillo, M.; Geisler, A.; Hobl, A.; Klein, H.U.; Krischel, D.; Meyer-Reumers, M.; Piel, C.; Blosser, H.; Kim, J.-W.; Marti, F.; Vincent, J.; Brandenburg, S.; Beijers, J.P.M.

    2001-01-01

    A cyclotron for proton therapy has to fulfill many requirements set by the specific operational and safety needs of a medical facility and the medical environment. These are for instance high extraction efficiency, high availability and reliability, simple and robust operation. ACCEL Instruments GmbH has refined the design concept of a medical cyclotron for the PSI PROSCAN project with the objective to use this cyclotron as the standard accelerator in complete proton therapy facilities, which ACCEL intends to market. Starting from the design, we have carried out further detail clarifications, optimizations and adaptations to the needs of PSI. The work was performed in a collaboration between ACCEL, NSCL and KVI in view of the requirements from the PSI PROSCAN project. An overview on the design will be given touching on subjects such as the 3D structural analysis of the coil, detailed magnetic modeling for optimization of the inner region and the spiral, optimization of the RF power, optimization of the cryogenic design based on available cryocoolers instead of a liquefaction plant and Monte Carlo simulations to estimate the heat balance produced by neutrons at 4K components

  15. First results from the new RIKEN superconducting electron cyclotron resonance ion source (invited).

    Science.gov (United States)

    Nakagawa, T; Higurashi, Y; Ohnishi, J; Aihara, T; Tamura, M; Uchiyama, A; Okuno, H; Kusaka, K; Kidera, M; Ikezawa, E; Fujimaki, M; Sato, Y; Watanabe, Y; Komiyama, M; Kase, M; Goto, A; Kamigaito, O; Yano, Y

    2010-02-01

    The next generation heavy ion accelerator facility, such as the RIKEN radio isotope (RI) beam factory, requires an intense beam of high charged heavy ions. In the past decade, performance of the electron cyclotron resonance (ECR) ion sources has been dramatically improved with increasing the magnetic field and rf frequency to enhance the density and confinement time of plasma. Furthermore, the effects of the key parameters (magnetic field configuration, gas pressure, etc.) on the ECR plasma have been revealed. Such basic studies give us how to optimize the ion source structure. Based on these studies and modern superconducting (SC) technology, we successfully constructed the new 28 GHz SC-ECRIS, which has a flexible magnetic field configuration to enlarge the ECR zone and to optimize the field gradient at ECR point. Using it, we investigated the effect of ECR zone size, magnetic field configuration, and biased disk on the beam intensity of the highly charged heavy ions with 18 GHz microwaves. In this article, we present the structure of the ion source and first experimental results with 18 GHz microwave in detail.

  16. Test results of a 5 kW fully superconducting homopolar motor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. K. [Woosuk University, Wanju (Korea, Republic of); Park, S. H.; Kim, Y.; Lee, S.; Joo, H. G.; Kim, W. S.; Choi, K. [Korea Polytechnic University,Siheong (Korea, Republic of); Hahm, S. Y. [Electrical Engineering and Science Research Institute,Seoul (Korea, Republic of)

    2013-05-15

    The superconducting Homopolar motor is manufactured and tested. Homopolar motor system is simple and solid as the field coil of the motor is fixed near the stator coil without rotating system. In this paper, a 5 kW fully superconducting homopolar motor which has high temperature superconducting armature and field coils is manufactured and tested in liquid nitrogen. The critical current test results of the used 2G superconducting wire, pancake coil for rotor winding and race-track coils for armature winding are reported. Also, the test result of rotating and operating performance is presented. The operating frequency is to be 5 Hz for low-speed rotating. The developed fully superconducting Homopolar motor is the world's first.

  17. Test results of a 5 kW fully superconducting homopolar motor

    International Nuclear Information System (INIS)

    Lee, J. K.; Park, S. H.; Kim, Y.; Lee, S.; Joo, H. G.; Kim, W. S.; Choi, K.; Hahm, S. Y.

    2013-01-01

    The superconducting Homopolar motor is manufactured and tested. Homopolar motor system is simple and solid as the field coil of the motor is fixed near the stator coil without rotating system. In this paper, a 5 kW fully superconducting homopolar motor which has high temperature superconducting armature and field coils is manufactured and tested in liquid nitrogen. The critical current test results of the used 2G superconducting wire, pancake coil for rotor winding and race-track coils for armature winding are reported. Also, the test result of rotating and operating performance is presented. The operating frequency is to be 5 Hz for low-speed rotating. The developed fully superconducting Homopolar motor is the world's first.

  18. Niobium thin film coating on a 500-MHz copper cavity by plasma deposition

    Energy Technology Data Exchange (ETDEWEB)

    Haipeng Wang; Genfa Wu; H. Phillips; Robert Rimmer; Anne-Marie Valente; Andy Wu

    2005-05-16

    A system using an Electron Cyclotron Resonance (ECR) plasma source for the deposition of a thin niobium film inside a copper cavity for superconducting accelerator applications has been designed and is being constructed. The system uses a 500-MHz copper cavity as both substrate and vacuum chamber. The ECR plasma will be created to produce direct niobium ion deposition. The central cylindrical grid is DC biased to control the deposition energy. This paper describes the design of several subcomponents including the vacuum chamber, RF supply, biasing grid and magnet coils. Operational parameters are compared between an operating sample deposition system and this system. Engineering work progress toward the first plasma creation will be reported here.

  19. Field profile and loading measurements on higher order modes in a two cell 500 MHz superconducting structure

    International Nuclear Information System (INIS)

    Barry, W.; Edighoffer, J.; Chattopadhyay, S.; Fornaca, S.

    1992-08-01

    The Infrared Free Electron Laser, being designed at LBL as part of the Chemical Dynamics Research Laboratory, is based on a 500 MHz superconducting linac driver that consists of five 4-cell structures of the CERN/DESY type. A 500 MHz, 2-cell version of this structure is being used in a joint Stanford/LBL/BNL program to study accelerator issues relevant to the FEL applications. As part of this study, field profile and loading measurements of higher order modes have been made on the prototype structure

  20. Liquid helium-free 15 T superconducting magnet at 4 K

    International Nuclear Information System (INIS)

    Sakuraba, J.; Mikami, Y.; Watazawa, K.; Watanabe, K.; Awaji, S.

    2000-01-01

    We have successfully demonstrated a 15.1 T liquid helium-free superconducting magnet with a room-temperature bore of 52 mm using a Nb 3 Sn/NbTi hybrid coil, Bi2223 current leads and two Gifford-McMahon cryocoolers. The magnet has 830 mm outside diameter, 1221 mm height and 720 kg weight. The magnet was cooled to 3.6 K in 114 h. A central magnetic field of 15.1 T was achieved in 38 min. The temperature of the coil increased to 5.7 K due to ac losses during the excitation, but it decreased to 4.0 K before reaching 15.1 T. The temperature of the coil remained at a constant value of 3.8 K over the 24 h of operation. The demonstration indicated the usefulness of a liquid helium-free superconducting magnet to generate high magnetic fields up to 15 T. (author)

  1. Cryogenic test facility at VECC, Kolkata

    International Nuclear Information System (INIS)

    Sarkar, Amit; Bhunia, Uttam; Pradhan, J.; Sur, A.; Bhandari, R.K.; Ranganathan, R.

    2003-01-01

    In view of proposed K-500 superconducting cyclotron project, cryogenic test facility has been set up at the centre. The facility can broadly be categorized into two- a small scale test facility and a large scale test facility. This facility has been utilized for the calibration of liquid helium level probe, cryogenic temperature probe, and I-B plot for a 7 T superconducting magnet. Spiral-shaped superconducting short sample with specific dimension and specially designed stainless steel sample holder has already been developed for the electrical characterisation. The 1/5 th model superconducting coil along with its quench detection circuit and dump resistor has also been developed

  2. Mechanical Design of Superconducting Accelerator Magnets

    International Nuclear Information System (INIS)

    Toral, F

    2014-01-01

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques

  3. Mechanical Design of Superconducting Accelerator Magnets

    CERN Document Server

    Toral, Fernando

    2014-07-17

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques.

  4. Mechanical Design of Superconducting Accelerator Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Toral, F [Madrid, CIEMAT (Spain)

    2014-07-01

    This paper is about the mechanical design of superconducting accelerator magnets. First, we give a brief review of the basic concepts and terms. In the following sections, we describe the particularities of the mechanical design of different types of superconducting accelerator magnets: solenoids, costheta, superferric, and toroids. Special attention is given to the pre-stress principle, which aims to avoid the appearance of tensile stresses in the superconducting coils. A case study on a compact superconducting cyclotron summarizes the main steps and the guidelines that should be followed for a proper mechanical design. Finally, we present some remarks on the measurement techniques.

  5. Field profile and loading measurements on higher order modes in a two cell 500 MHz superconducting structure

    International Nuclear Information System (INIS)

    Barry, W.; Edighoffer, J.; Chattopadhyay, S.; Fornaco, S.

    1992-01-01

    The Infrared Free Electron Laser, being designed at LBL as part of the Chemical Dynamics Research Laboratory, is based on a 500 MHz superconducting linac driver that consists of five 4-cell structures of the CERN/DESY type. A 500 MHz, 2-cell version of this structure is being used in a joint Stanford/LBL/BNL program to study accelerator issues relevant to the FEL applications. As part of this study, field profile and loading measurements of higher order modes have been made on the prototype structure. (Author) 3 refs., 2 figs., tab

  6. [Cyclotron based nuclear science

    International Nuclear Information System (INIS)

    1991-08-01

    This report contains descriptions of research programs carried out by Institute staff, as well as progress on new instrumentation during the period, April 1, 1990, to March 31, 1991. The K500 cyclotron and ECR source provided beam for 4140 hours during the period. The beam was actually available for experiments 1927.50 hours and 1110.50 hours was devoted to developing new beams and exploring cyclotron performance. A wide range of beams from protons to Xe with energies from 2.4 MeV/u to 60 MeV/U have been used in experiments. The highest total energy beam accelerated was 35 MeV/u 63 Cu. The ECR source, made a tremendous improvement in accelerator performance and reliability. Substantial amounts of beam time were devoted to investigations of hot nuclei, electron-positron, giant resonances, atomic effects of high velocity ion beams, astrophysics related reactions and proton and alpha bremsstrahlung. Scientific accomplishments included determination of the heat capacity of nuclei through new insight into the level densities and establishing a lower limit for electron positron resonances a factor of ten better than previous measurements. The proton spectrometer, constructed for studies of the Gamow-Teller interaction is complete, and initial physics measurements will be made in the next few months. All of the BaF 2 crystals have been delivered and acceptance tests are underway. A K=315 MDM spectrometer has been obtained from Oxford University and is scheduled for installation in Spring 1992, after removal of the K=150 Enge split pole spectrometer. Institute groups continue participation in MEGA, instrumentation projects for RHIC, and few nucleon studies at LAMPF and KEK. Reports of these activities are included

  7. LHC Report: superconducting circuit powering tests

    CERN Multimedia

    Mirko Pojer

    2015-01-01

    After the long maintenance and consolidation campaign carried out during LS1, the machine is getting ready to start operation with beam at 6.5 TeV… the physics community can’t wait! Prior to this, all hardware and software systems have to be tested to assess their correct and safe operation.   Most of the cold circuits (those with high current/stored energy) possess a sophisticated magnet protection system that is crucial to detect a transition of the coil from the superconducting to the normal state (a quench) and safely extract the energy stored in the circuits (about 1 GJ per dipole circuit at nominal current). LHC operation relies on 1232 superconducting dipoles with a field of up to 8.33 T operating in superfluid helium at 1.9 K, along with more than 500 superconducting quadrupoles operating at 4.2 or 1.9 K. Besides, many other superconducting and normal resistive magnets are used to guarantee the possibility of correcting all beam parameters, for a total of mo...

  8. Design, performance, and economics of 50-kW and 500-kW vertical axis wind turbines

    Science.gov (United States)

    Schienbein, L. A.; Malcolm, D. J.

    1983-11-01

    A review of the development and performance of the DAF Indal 50-kW vertical axis Darrieus wind turbine shows that a high level of technical development and reliability has been achieved. Features of the drive train, braking and control systems are discussed and performance details are presented. Details are also presented of a 500-kW VAWT that is currently in production. A discussion of the economics of both the 50-kW and 500-kW VAWTs is included, showing the effects of charge rate, installed cost, operating cost, performance, and efficiency.

  9. The beam steering system of the cyclotron U-120K; Sistema razvodki puchkov tsiklotrona U-120K

    Energy Technology Data Exchange (ETDEWEB)

    Borkova, A; Ivan, J; Trejbal, Z; Dmitrievskij, V P; Pavlov, D V; Chesnov, A F; Chesnova, S I

    1991-12-31

    The calculation of the beam transport system of the isochronous cyclotron U-120K is presented. This system realizes the beam transport with given parameters to six distant targets specializing in the production of radioactive isotopes, the biomedicine investigation, the experimental nuclear physics. At chosen parameters of lenses and bending magnets the beam size is {<=} 1x1 cm and the energy resolution in the monoenergetic line is less than 0.1%. 4 refs.; 6 figs.; 1 tab.

  10. Superconductivity in a new YBaCuO compound at 105 K

    International Nuclear Information System (INIS)

    Kirschner, I.; Bankuti, J.; Gal, M.; Torkos, K.; Solymos, K.G.; Horvath, G.

    1987-01-01

    A superconducting transition has been detected in a (Y 0.8 Ba 0.2 )(CuO 4-δ ) 2 compound by electrical and magnetic measurements. The resistivity begins to decrease at 173 K and the zero-resistivity state sets in at 105 K

  11. Technical Note: Building a combined cyclotron and MRI facility: Implications for interference

    Energy Technology Data Exchange (ETDEWEB)

    Hofman, Mark B. M.; Kuijer, Joost P. A.; Ridder, Jan Willem de; Perk, Lars R.; Verdaasdonk, Rudolf M. [Physics and Medical Technology, VU University Medical Center, Amsterdam 1007 MB (Netherlands) and BV Cyclotron VU, Amsterdam 1081HV (Netherlands)

    2013-01-15

    Purpose: With the introduction of hybrid PET/MRI systems, it has become more likely that the cyclotron and MRI systems will be located close to each other. This study considered the interference between a cyclotron and a superconducting MRI system. Methods: Interactions between cyclotrons and MRIs are theoretically considered. The main interference is expected to be the perturbation of the magnetic field in the MRI due to switching on or off the magnetic field of the cyclotron. MR imaging is distorted by a dynamic spatial gradient of an external inplane magnetic field larger than 0.5-0.04 {mu}T/m, depending on the specific MR application. From the design of a cyclotron, it is expected that the magnetic fringe field at large distances behaves as a magnetic dipolar field. This allows estimation of the full dipolar field and its spatial gradients from a single measurement. Around an 18 MeV cyclotron (Cyclone, IBA), magnetic field measurements were performed on 5 locations and compared with calculations based upon a dipolar field model. Results: At the measurement locations the estimated and measured values of the magnetic field component and its spatial gradients of the inplane component were compared, and found to agree within a factor 1.1 for the magnetic field and within a factor of 1.5 for the spatial gradients of the field. In the specific case of the 18 MeV cyclotron with a vertical magnetic field and a 3T superconducting whole body MR system, a minimum distance of 20 m has to be considered to prevent interference. Conclusions: This study showed that a dipole model is sufficiently accurate to predict the interference of a cyclotron on a MRI scanner, for site planning purposes. The cyclotron and a whole body MRI system considered in this study need to be placed more than 20 m apart, or magnetic shielding should be utilized.

  12. Vancouver Cyclotron Conference

    International Nuclear Information System (INIS)

    Clark, David J.

    1993-01-01

    Although no longer on the high energy frontier, the cyclotron field is still a major scientific growth area. Its progress is highlighted at the international conference on cyclotron design, development and utilization held at intervals of about three years, under the auspices of the International Union of Pure and Applied Physics (IUPAP). Vancouver, surrounded by mountains, water and some cyclotrons, provided a pleasant setting for the 13th Conference, held last summer. With over 200 cyclotrons in operation around the world, the attendance, 241 delegates and 26 industrial exhibitors, was a near record, reflecting the flourishing state of the field. The early sessions covered the initial operation of new or upgraded cyclotron facilities. Major facilities completed since the previous Conference in Berlin in May 1989 included the 400 MeV ring cyclotron at Osaka, the U400M cyclotron at Dubna which will be coupled to the U400 to give 20 MeV nucléon uranium beams, the 130 MeV cyclotron at Jyvaskyla (in Finland, the furthest north!), the 110 MeV JAERI machine in Japan, and the 65 MeV proton therapy cyclotron in Nice. Among the facility upgrades were the KFA cyclotron at Julich which will inject the 2.5 GeV storage ring COSY, and the addition of an FM mode to the K=200 CW mode at Uppsala to give protons up to 180 MeV. The impressive current of 1.5 mA at 72 MeV obtained from the PSI Injector II will soon be injected into the 590 MeV ring

  13. Auxiliary accelerating system for TRIUMF cyclotron

    International Nuclear Information System (INIS)

    Zach, M.; Fong, K.; Laxdal, R.; Mackenzie, G.H.; Pacak, V.; Pearson, J.; Richardson, J.R.; Stanford, G.; Worsham, R.

    1990-06-01

    A 92 MHz auxiliary accelerating cavity has been designed and manufactured for installation in the TRIUMF cyclotron. Operating at the fourth harmonic of the RF with a peak voltage of 150 kV, it almost doubles the present energy gain per turn in the 400-500 MeV range, and reduces by ∼50% the stripping loss of the H - beam. This significant improvement will allow a substantial increase in the extracted current above the present routine level of 150μA while maintaining the same levels of residual radioactivity. The system is completed and being commissioned. A description of the design and commissioning procedures is presented, and results of beam tests given. (Author) 7 refs., 5 figs

  14. Hall effect of K-doped superconducting thin films

    Energy Technology Data Exchange (ETDEWEB)

    Son, Eunseon; Lee, Nam Hoon; Kang, Won Nam [Dept. of physics, Sungkyunkwan University, Suwon (Korea, Republic of); Hwang, Tae Jong; Kim, Dong Ho [Dept. of physics, Yeungnam University, Gyeongsan(Korea, Republic of)

    2013-09-15

    We have studied Hall effect for potassium (K)-doped BaFe{sub 2}As{sub 2}superconducting thin films by analyzing the relation between the longitudinal resistivity (ρ{sub xy}) and the Hall resistivity (ρ{sub xy}). The thin films used in this study were fabricated on Al{sub O3} (000l) substrates by using an ex-situ pulsed laser deposition (PLD) technique under a high-vacuum condition of ∼10{sup -6} Torr. The samples showed the high superconducting transition temperatures (T{sub C}) of ∼40 K. The ρ{sub xx} and ρ{sub xy}the for K-doped BaFeAs{sub 2} thin films were measured by using a physical property measurement system (PPMS) with a temperature sweep (T-sweep) mode at an applied current density of 100 A/cm{sup 2} and at magnetic fields from 0 up to 9 T. We report the T-sweep results of the ρ{sub xx} and the ρ{sub xy} to investigate Hall scaling behavior on the basis of the relation of ρ{sub xy} = A(ρ{sub xy}){sup β}. The ρ{sub xx} values are 3.0 ± 0.2 in the c-axis-oriented K-doped BaFeAs{sub 2} thin films, whereas the thin films with various oriented-directions like a polycrystal showed slightly lower β than that of c-axis-oriented thin films. Interestingly, the β value is decreased with increasing magnetic fields.

  15. Optimum copper to superconductor ratio in cables for superconducting magnets at 1.9 K

    International Nuclear Information System (INIS)

    Wolf, R.

    1994-01-01

    In this paper the optimum copper to superconducting ratio is calculated to prevent quenching for superconducting cables used in accelerator magnets like the LHC dipoles, operating in superfluid helium at 1.9K. The duration of the perturbations leading to a quench are estimated from flux measurements made with pickup coils in the LHC dipole models. The optimum copper to superconducting ratio is then found by studying the minimum quench energy and the influence of the length and the duration or the perturbation and heat transfer to the surroundings. A comparison is made of the behavior at temperatures of 1.9 and 4.3 K

  16. Superconductivity of tin and lead after heavy ion irradiation below 7.2 K

    International Nuclear Information System (INIS)

    Klaumuenzer, S.

    1978-01-01

    In this work the influence of radiation defects induced by heavy ion irradiation at low temperatures on the specific residual resistivity, the critical temperature of superconductivity, and the width of the resistive-superconductive phase transition have been measured for lead and tin as a function of dose and subsequent isochronous annealing. In the case of lead the critical magnetic field parallel to the surface of the sample, which in a wide range of defect contrations is identical with the surface superconductivity critical field, also has been measured at 5 K and 6 K as a function of dose and subsequent isochronous annealing. As projectiles 25 MeV oxygen ions have been used for irradiation, with a sufficiently low particle flux to obtain irradiation temperatures below about 7.2 K. However these temperatures are large enough to allow for free motion of interstitial atoms in the case of lead. For tin the results presented here also suggest free motion of the defects. (orig./WBU) [de

  17. Crystal structure of 200 K-superconducting phase in sulfur hydride system

    Energy Technology Data Exchange (ETDEWEB)

    Einaga, Mari; Sakata, Masafumi; Ishikawa, Takahiro; Shimizu, Katsuya [KYOKUGEN, Graduate School of Engineering Science, Osaka Univ. (Japan); Eremets, Mikhail; Drozdov, Alexander; Troyan, Ivan [Max Planck Institut fuer Chemie, Mainz (Germany); Hirao, Naohisa; Ohishi, Yasuo [JASRI/SPring-8, Hyogo (Japan)

    2016-07-01

    Superconductivity with the critical temperature T{sub c} above 200 K has been recently discovered by compression of H{sub 2}S (or D{sub 2}S) under extreme pressure. It was proposed that these materials decompose under high pressure to elemental sulfur and hydride with higher content of hydrogen which is responsible for the high temperature superconductivity. In this study, we have investigated that the crystal structure of the superconducting compressed H{sub 2}S and D{sub 2}S by synchrotron x-ray diffraction measurements combined with electrical resistance measurements at room and low temperatures. We found that the superconducting phase is in good agreement with theoretically predicted body-centered cubic structure, and coexists with elemental sulfur, which claims that the formation of 3H{sub 2}S → 2H{sub 3}S + S is occured under high pressure.

  18. The NSCL cyclotron gas stopper – Entering commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, S. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Bollen, G. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI (United States); Facility for Rare Isotope Beams, East Lansing, MI (United States); Chouhan, S. [Facility for Rare Isotope Beams, East Lansing, MI (United States); Das, J.J. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Green, M. [Facility for Rare Isotope Beams, East Lansing, MI (United States); Magsig, C. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Morrissey, D.J. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Ottarson, J.; Sumithrarachchi, C. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Villari, A.C.C.; Zeller, A. [Facility for Rare Isotope Beams, East Lansing, MI (United States)

    2016-06-01

    Linear gas stopping cells have been used successfully at NSCL to slow down ions produced by projectile fragmentation from the 100 MeV/u to the keV energy range. These ‘stopped beams’ have first been used for low-energy high precision experiments and more recently for NSCLs re-accelerator ReA. A gas-filled reverse cyclotron is currently under construction by the NSCL to complement the existing stopping cells: Due to its extended stopping length, efficient stopping and fast extraction is expected even for light and medium-mass ions, which are difficult to thermalize in linear gas cells. The device is based on a 2.6 T maximum-field cyclotron-type magnet to confine the injected beam while it is slowed down in ≈100 mbar of LN{sub 2}-temperature helium gas. Once thermalized, the beam will be transported to the center of the device by a traveling-wave RF-carpet system, extracted along the symmetry axis with an ion conveyor and miniature RF-carpets, and accelerated to a few tens of keV of energy for delivery to the users. The superconducting magnet has been constructed on a 60 kV platform and energized to its nominal field strength. The magnet’s two cryostats use 3 cryo-refrigerators each and liquid-nitrogen cooled thermal shields to cool the coil pair to superconductivity. This concept, chosen not to have to rely on external liquid helium, has been working well. Measurements of axial and radial field profiles confirm the field calculations. The individual RF-ion guiding components for low-energy ion transport through the device have been tested successfully. The beam stopping chamber with its 0.9 m-diameter RF carpet system and the ion extraction system are being prepared for installation inside the magnet for low-energy ion transport tests.

  19. Electron cyclotron emission measurements at the stellarator TJ-K

    Energy Technology Data Exchange (ETDEWEB)

    Sichardt, Gabriel; Ramisch, Mirko [Institut fuer Grenzflaechenverfahrenstechnik und Plasmatechnologie, Universitaet Stuttgart (Germany); Koehn, Alf [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2016-07-01

    Electron temperature (T{sub e}) measurements in the magnetised plasmas of the stellarator TJ-K are currently performed by means of Langmuir probes. The use of these probes is restricted to relatively low temperatures and the measurement of temperature profiles requires the acquisition of the local current-voltage characteristics which limits strongly the sampling rate. As an alternative, T{sub e} can be measured using the electron cyclotron emission (ECE) that is generated by the gyration of electrons in magnetised plasmas. Magnetic field gradients in the plasma lead to a spatial distribution of emission frequencies and thus the measured intensity at a given frequency can be related to its point of origin. The T{sub e} dependence of the intensity then leads to a temperature profile along the line of sight for Maxwellian velocity distributions. A diagnostic system for T{sub e} measurements using ECE is currently being set up at TJ-K. When non-thermal electrons are present the emission spectrum changes dramatically. Therefore, the ECE can also be used to investigate the contribution of fast electrons to previously observed toroidal net currents in TJ-K. Simulations are used to examine the role of electron drift orbits in generating these currents.

  20. Superconductivity of k-(BEDT-TTF) sub 2 Cu[N(CN) sub 2]I under pressure

    CERN Document Server

    Kushch, N D; Yagubskii, E B; Ishiguro, T

    2001-01-01

    The insulating state of k-(BEDT-TTF) sub 2 Cu[N(CN) sub 2]I salt appearing at ambient pressure at low temperatures is suppressed by hydrostatic pressure. The resistive measurement showed that in high-quality crystals the emerging metallic state reveals superconductivity. The superconducting state with the transition temperature of about 8 K is stable at pressures higher than 0.1 GPa

  1. ECR plasma cleaning for superconducting cavities

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-02-01

    A superconducting linac has been operating well as a heavy ion energy booster of the tandem accelerator at JAERI since 1994. Forty superconducting quarter wave resonators are used in the linac. They have high performances in average. Some of them are, however, suffering from 'Q-disease' that has been caused by hydrogen absorption into niobium during electro-polishing and the precipitation of niobium-hydrides on the surface at the vicinity of about 120K during precooling. A method of electron cyclotron resonance (ECR) plasma cleaning was applied to spare resonator in order to investigate if it is useful as a curing method of Q-disease. ECR plasma was excited in the resonator by 2.45 GHz microwave in a magnetic field of about 87.5 mT. In the first preliminary experiments, hydrogen, helium, water and oxigen gases were investigated. Every case was done at a pressure of about 3x10{sup -3} Pa. The results show that apparent recovery from Q-disease was found with helium and oxigen gases. (author)

  2. Recent development and progress of IBA cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Kleeven, W., E-mail: Willem.Kleeven@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Abs, M., E-mail: Michel.Abs@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Delvaux, J.L., E-mail: Jean-Luc.Delvaux@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Forton, E., E-mail: Eric.Forton@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Jongen, Y., E-mail: Yves.Jongen@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Medeiros Romao, L., E-mail: Luis.MedeirosRomao@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Nactergal, B., E-mail: Benoit.Nactergal@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Nuttens, V., E-mail: Vincent.Nuttens@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Servais, T., E-mail: Thomas.Servais@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Vanderlinden, T., E-mail: Thierry.Vanderlinden@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium); Zaremba, S., E-mail: Simon.Zaremba@iba-group.com [Ion Beam Applications s.a. Chemin du Cyclotron 3, Louvain-la-Neuve (Belgium)

    2011-12-15

    Several cyclotron development projects were recently realized by Ion Beam Applications S.A. (IBA). This contribution presents three of them: (i) the intensity enhancement of the Cyclone 30 cyclotron, a machine mainly used for the production of SPECT isotopes. This project is related with the increased demand for {sup 201}Tl because of the shortage of Mo/Tc generators from nuclear reactors, (ii) development of a new versatile multiple-particle K = 30 isotope-production cyclotron (the Cyclone 30XP) being able to accelerate H{sup -}, D{sup -} and also {alpha}-particles. The {alpha}-beam of this cyclotron will allow the production of new therapeutic isotopes (e.g. {sup 211}At) and (iii) commissioning of the Cyclone 70 cyclotron installed for Arronax in France. This machine is similar to the C30XP but provides higher energy (K = 70) and allows research on new types of medical isotopes.

  3. An experimental mechanical switch for 3 kA driven by superconducting coils

    International Nuclear Information System (INIS)

    Herman, H.J.; Ten Haken, B.; Van de Klundert, L.J.M.

    1986-01-01

    Usually mechanical switches that are built for use in superconducting circuits are driven in some way by a rod which is controlled at room temperature. In this paper, an alternative method to drive the electrodes of the switch is reported. In fact the new device is a superconducting relay that uses an antiseries connection of two superconducting air-core coils. The repulsing force of these relay coils enables the switch to be closed by applying a pressure to the electrodes. The off-state is effected by a set of springs which interrupt the electrodes when the coil current is switched off. We realized that this electro-magnetic method of producing large forces could be promising for driving a mechanical switch. The desired method was demonstrated by an experimental model. A switch-on resistance of 8*10 -8 Ω with a switch current of 3 kA and a contact force of 20 kN was measured

  4. Comparing microbubble cavitation at 500 kHz and 70 kHz related to micellar drug delivery using ultrasound.

    Science.gov (United States)

    Diaz de la Rosa, Mario A; Husseini, Ghaleb A; Pitt, William G

    2013-02-01

    We have previously reported that ultrasonic drug release at 70kHz was found to correlate with the presence of subharmonic emissions. No evidence of drug release or of the subharmonic emissions were detected in experiments at 500kHz. In an attempt to understand the difference in drug release behavior between low- and mid-frequency ultrasound, a mathematical model of a bubble oscillator was developed to explore the difference in the behavior of a single 10-μm bubble under 500- and 70-kHz ultrasound. The dynamics were found to be fundamentally different; the 500-kHz bubble follows a period-doubling route to chaos while a 70-kHz bubble follows an intermittent route to chaos. We propose that this type of "intermittent subharmonic" oscillation behavior is associated with the drug release observed experimentally. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Evidence for phonon-mediated coupling in superconducting Ba0.6K0.4BiO3

    International Nuclear Information System (INIS)

    Hinks, D.G.; Dabrowski, B.; Richards, D.R.; Jorgensen, J.D.; Pei, S.; Zasadzinski, J.F.

    1989-01-01

    Superconducting Ba 0.6 K 0.4 BiO 3 , with a T c of 30 K, shows a large 18 O isotope effect which indicates that phonons are involved in the pairing mechanism. Infrared reflectivity measurements indicate a value for the superconducting gap consistent with moderate coupling (2Δ/k T c = 3.5 ± 0.5). A mediating energy for pairing of about 40 meV would be required to obtain a T c of 30 K. Strong coupling of electrons by optical phonons (which are present in this material with energies up to 80 meV) could account for the observed transition temperature. Recent tunneling spectroscopy shows the presence of strongly coupled optical phonons in the 40 to 70 meV region, indicating that superconductivity in this material may be phonon mediated

  6. New type sector cyclotron and improvement of EULIMA project

    International Nuclear Information System (INIS)

    Gao, Shuyang

    1988-01-01

    In this paper the two sorts of new type sector cyclotron have been discussed. Both of them remain with the same structure as straight-side sector magnet; but the annular shim systems are added on the pole faces of the every sectors. One of them has one group of the shim system; another has the three groups on the every sector. The analytical expressions of the magnetic field for the structure have been given. The linear motion stability of the particles has been proved. The new type of the compact superconducting cyclotron in the median energy is put forward as an instance for its application to the EULIMA project. (author)

  7. Development of a thermally switched superconducting rectifier for 100 kA

    NARCIS (Netherlands)

    Mulder, G.B.J.; Mulder, G.B.J.; ten Kate, Herman H.J.; Krooshoop, Hendrikus J.G.; van de Klundert, L.J.M.; van de Klundert, L.J.M.

    1991-01-01

    A full-wave superconducting rectifier for 100 kA has been developed. Typical design values of this device are: a secondary current of 100 kA, a primary amplitude of 20 A, an operating frequency of 0.5 Hz, and an average power on the order of 100 W. The rectification is achieved by means of thermally

  8. Design of large aperture 500 MHz 5-cell superconducting cavity

    International Nuclear Information System (INIS)

    Wei Yelong; Feng Ziqiang; Lu Changwang; Yu Haibo; Liu Jianfei; Hou Hongtao; Ma Zhenyu; Mao Dongqing

    2012-01-01

    With the potential application of Energy Recovery Linac (ERL), the superconducting (SC) cavities were developed to deliver much higher current than before. Nowadays, the current of the international SC accelerator designed has already exceeded 100 mA. This paper presents the design of a new 500 MHz 5-cell SC cavity (SINAP 5-cell cavity), in which the parameters r/Q= 515.5 Ω of the fundamental mode and the geometry factor G=275.8 are under an acceptable Radio Frequency (RF) field level. (B peak /E acc =4.31 mT/MV/m and E peak /E acc =2.48). This design employs a larger beam pipe to propagate the Higher Order Modes (HOMs) out of the cavity and increases the damping efficiently for the dangerous HOMs. By simulation technique, it has been found that almost all the dangerous HOMs (including TE 111 , TM 110 , and TM 011 ) can be propagated into the beam pipe and are absorbed by ferrite absorbers, when the beam pile is enlarged. Finally, the loss factor for the new 5-cell cavity is also calculated. (authors)

  9. Superconducting magnets for the RAON electron cyclotron resonance ion source.

    Science.gov (United States)

    Choi, S; Kim, Y; Hong, I S; Jeon, D

    2014-02-01

    The RAON linear accelerator of Rare Isotope Science Project has been developed since 2011, and the superconducting magnet for ECRIS was designed. The RAON ECR ion source was considered as a 3rd generation source. The fully superconducting magnet has been designed for operating using 28 GHz radio frequency. The RAON ECRIS operates in a minimum B field configuration which means that a magnetic sextupole field for radial confinement is superimposed with a magnetic mirror field for axial confinement. The highest field strength reaches 3.5 T on axis and 2 T at the plasma chamber wall for operating frequency up to 28 GHz. In this paper, the design results are presented of optimized superconducting magnet consisting of four solenoids and sextupole. The prototype magnet for ECRIS was fabricated and tested to verify the feasibility of the design. On the basis of test results, a fully superconducting magnet will be fabricated and tested.

  10. Superconducting Fullerene Nanowhiskers

    Directory of Open Access Journals (Sweden)

    Yoshihiko Takano

    2012-04-01

    Full Text Available We synthesized superconducting fullerene nanowhiskers (C60NWs by potassium (K intercalation. They showed large superconducting volume fractions, as high as 80%. The superconducting transition temperature at 17 K was independent of the K content (x in the range between 1.6 and 6.0 in K-doped C60 nanowhiskers (KxC60NWs, while the superconducting volume fractions changed with x. The highest shielding fraction of a full shielding volume was observed in the material of K3.3C60NW by heating at 200 °C. On the other hand, that of a K-doped fullerene (K-C60 crystal was less than 1%. We report the superconducting behaviors of our newly synthesized KxC60NWs in comparison to those of KxC60 crystals, which show superconductivity at 19 K in K3C60. The lattice structures are also discussed, based on the x-ray diffraction (XRD analyses.

  11. New design for a medical cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, M

    1985-12-01

    The Oxford Instruments Group PLC, have designed a 30 MeV energy proton cyclotron incorporating a super-conducting magnet and a novel RF accelerating cavity. The energy range is suitable for the production of isotopes such as /sup 67/Ga, /sup 111/In, /sup 123/I and /sup 201/Tl, and the short lived isotopes of carbon, nitrogen, oxygen and fluorine for use in Positron Emmission Tomography (PET). A new magnet and RF cavity design permit a considerable power and weight reduction and a compact size (1.5m dia x 1.9m high), allowing the cyclotron to be transported to a shielded site as an assembly after factory testing. A method of beam extraction has been adopted which minimises activation of the accelerator components and so allows hands on maintenance to be carried out when required.

  12. Survey of magnetic fields near BPA 230-kV and 500-kV transmission lines

    International Nuclear Information System (INIS)

    Perrin, N.; Aggarwal, R.P.

    1991-01-01

    The purpose of this study was to characterize typical levels and variability of 60Hz magnetic fields at the centerline and edge of right-of-way of Bonneville Power Administration (BPA) 230-kV and 500-kV transmission lines. This was accomplished by taking magnetic field measurements at over 800 spans in Oregon and Washington. The spans were sampled using a stratified random sampling procedure with region (East vs. West), voltage (230-kV vs 500-kV), and circuit configuration as strata. There were five different circuit configuration groups for each region/voltage category requiring a total of 200 strata. Magnetic field measurements were taken at 13 locations under each span using an EMDEX-C as a survey meter. Additional information recorded for each span included conductor height (at 10 locations), right-of-way width, longitudinal and lateral slope, time of day, vegetation, terrain, weather conditions, temperature, wind speed, span length and presence of other lines in the corridor. 9 refs., 17 figs., 26 tabs

  13. Modular beam diagnostics instrument design for Cyclotrons

    International Nuclear Information System (INIS)

    Chaddha, N.; Bhole, R.B.; Sahoo, S.; Nandy, P.P.; Pal, S.

    2012-01-01

    The Cyclotrons at VECC, Kolkata i.e. Room Temperature Cyclotron (RTC) and Superconducting Cyclotron (SCC) comprise of internal and external Beam Diagnostic systems. These systems provide the beam developer with position, intensity, beam profile, a visual impression of the size and shape of ion beam, and operational control over diagnostic components like 3-finger probe, Beam Viewer probe, Deflector probe, Faraday cup, X-Y slit, Beam viewer etc. Automation of these components was initially done using customised modules for individual sub-system. An expansion of this facility and various levels of complexity demand modular design to cater easy modification and upgradation. The overall requirements are analysed and modular cards are developed based on basic functionalities like valve operation, probe/slit/viewer control, position read-out, Interlock, aperture control of beam line and communication. A 32-bit Advanced RISC Machine (ARM) based card with embedded EPICS is chosen as the master controller and FPGA/microcontroller is used for functional modules. The paper gives a comprehensive description of all modules and their integration with the control system. (author)

  14. Examination of tracer method using 43K produced with a cyclotron

    International Nuclear Information System (INIS)

    Yuida, Koichi; Kawarazaki, Yuji; Shibuya, Masao; Nozaki, Tadashi.

    1980-01-01

    The 43 K tracer produced with a cyclotron is contaminated with about the same amount of 42 K. During first 43 hours after the production, the rate of attenuation of its radioactivity was greater than the theoretical value of 43 K (half-life 22.4 hours) because of the rapid attenuation of radioactivity of the contaminating 42 K (half-life 12.4 hours). After that, however, the rate of attenuation in the radioactivity of 43 K tracer followed the attenuation curve of 22.4 hr half-life, i.e., the radioactivity of the contaminating 42 K was negligible. The potassium chloride fertilizer labelled with 43 K-tracer (or 42 K-tracer) was applied for 8 days (or 4.5 days in case of 42 K) to 2-month-old rice plants grown by hydroponics, and for 7 days to rice plants grown on soil (at ripening stage). The rice plants were then dried for 24 hours at 70 deg C, and the radioactivity was measured by a scintillation counter. 43 K was able to be traced for 13.3 days in the plants grown by hydroponics, and 42 K for 5.4 days, but 43 K was able to be traced only for 7.4 days in the plants grown on soil which absorb 43 K poorly. Since 43 K and 42 K are γ-ray emittors, and the energy is not low, microautoradiograms were not able to be made, but macroautoradiograms were made. The autoradiograms for 43 K and 42 K did not differ in resolution, and both were clear. The radioactivity of 43 K did not diminish so rapidly as 42 K, but was lost in one month. Such character of 43 K is beneficial both for tracer experiments and for the prevention of environmental pollution. (Kaihara, S.)

  15. Update on the VECC-TRIUMF collaboration for superconducting e-Linac development

    International Nuclear Information System (INIS)

    Naik, V.; Dechoudhury, S.; Mondal, M.

    2013-01-01

    A 50 MeV 100 kW cw superconducting electron linac (e-Linac) will be used as photo-fission driver for the ANURIB facility at Variable Energy Cyclotron Centre. In the first phase a 10 MeV Injector is being developed in collaboration with TRIUMF Canada, who will also be using an e-Linac driver for their ARIEL (Advanced Rare IsotopE Laboratory) upgrade. The VECC e-Linac will be installed at the upcoming Rajarhat campus. For the initial R and D on the Injector an e-Linac test area is being set-up in one of the experimental caves of the K130 cyclotron at the Salt Lake campus. The Injector will be tested using a 100 kV gun. A Capture Cryo Module (CCM) consisting of two beta=1, 1.3 GHz, single-cell niobium cavities is being designed and built indigenously. The CCM will be used for pre-acceleration of the beam from the gun to around 400 keV before injection in to the ICM. The ICM will be built and tested at TRIUMF and a test area has been set-up at TRIUMF for the purpose. Detailed status report on various components of the e-Linac will be presented. (author)

  16. Superconducting Sweet-Spot in Microcrystalline Graphite Revealed by Point-Contact Spectroscopy

    Science.gov (United States)

    Arnold, F.; Nyéki, J.; Saunders, J.

    2018-05-01

    In this letter we describe the observation of a magnetic field dependent electronic gap, suggestive of local superconductivity, in the point-contact spectrum of micro-crystalline graphite. Magnetic field dependent point-contact spectroscopy was carried out at a temperature of 1.8K using an etched aluminium tip. At zero field a gap structure in the differential conductance is observed, showing a gap of Δ = 4.2 meV. On applying magnetic fields of up to 500mT, this gap gradually closes, following the theoretical prediction by Ginzburg and Landau for a fully flux-penetrated superconductor. By applying BCS-theory, we infer a critical superconducting temperature of 14K.

  17. Deposition of superconducting (Cu, C)-Ba-O films by pulsed laser deposition at moderate temperature

    International Nuclear Information System (INIS)

    Yamamoto, Tetsuro; Kikunaga, Kazuya; Obara, Kozo; Terada, Norio; Kikuchi, Naoto; Tanaka, Yasumoto; Tokiwa, Kazuyasu; Watanabe, Tsuneo; Sundaresan, Athinarayanan; Shipra

    2007-01-01

    Superconducting (Cu, C)-Ba-O thin films have been epitaxially grown on (100) SrTiO 3 at a low growth temperature of 500-600 deg. C by pulsed laser deposition. The dependences of their crystallinity and transport properties on preparation conditions have been investigated in order to clarify the dominant parameters for carbon incorporation and the emergence of superconductivity. It has been revealed that the CO 3 content in the films increases with increasing both the parameters of partial pressure of CO 2 during film growth and those of growth rate and enhancement of superconducting properties. The present study has also revealed that the structural and superconducting properties of the (Cu, C)-Ba-O films are seriously deteriorated by the irradiation of energetic particles during deposition. Suppression of the radiation damage is another key for a high and uniform superconducting transition. By these optimizations, a superconducting onset temperature above 50 K and a zero-resistance temperature above 40 K have been realized

  18. A 25 kA, 2T, 78 kJ, 52 litre superconducting test coil. Strength calculations and construction

    NARCIS (Netherlands)

    ten Kate, Herman H.J.; Holtslag, A.H.M.; Knoben, J.; Steffens, H.A.; van de Klundert, L.J.M.

    1983-01-01

    Within the scope of our research program for a 25 kA superconducting rectifier, we have built a 25 kA s.c. coil being a single layer solenoid with a bore of 0.45 meter and a volume of 52 litre. The starting point for the design was to avoid any metallic structural material. This unique coil consists

  19. Bunker door interlock limit issues of K-130 cyclotron, VECC

    International Nuclear Information System (INIS)

    Srihari, K.; Ravishankar, R.; Mitra, M.S.; Mishra, S.K.; Bandyopadhyay, T.; Sarkar, P.K.

    2011-01-01

    The K-130 cyclotron is in operation at VECC, Kolkata. Recently modernization of the cyclotron has taken place. Central region modification has increased reasonable internal beam current. During the tuning of the projectiles, loss of beam is unavoidable and projectiles hitting different parts of the machine inside the vacuum chamber . These interactions produce prompt radiation comprising neutron and gamma. However machine bunker is not accessible during the operation of the machine. The induced activity produced because of interactions of the primary and secondary radiation a radiation hazardous environment during the shut down for the related maintenance work. Area radiation monitors placed at machine bunker room have the interlock with massive shield door of the bunker. Area radiation monitors are set to specified limiting value, lower than that will allow to open the shield door in normal condition. As, the internal beam current being increased and the probability of beam spread being more. Consequently generation of induced activity is also high leading to delay in machine bunker door opening because of the interlock settings. Radiation dose mapping after a long operation of the machine was done for the different strategic points (The locations mainly people access immediate after shut down). Different consequences and remedial measures being presented in paper to raise the dose rate limit level for the interlocks between the area radiation monitors with machine bunker door, keeping in mind of the regulatory requirements. Raising the limit of dose rate limiting value will minimize the waiting time to access the machine bunker which will increase the duty factor of the machine. (author)

  20. Performance improvement of 100 kW high frequency transmitter for CW operation

    International Nuclear Information System (INIS)

    Kwak, J. G.; Yoon, J. S.; Bae, Y. D.; Cho, C. G.; Wang, S. J.; Lee, K. D.

    2001-08-01

    For the plasma heating of KSTAR(Korea Superconducting Tokamak Advanced Research)by using ICH(Ion Cyclotron Heating), it is designed that the selective ion heating and current drive are performed by the transmitter with the rf power of 8 MW in the frequency range of 25-60 MHz. 100 kW HF transmitter was constructed for the high voltage/current test of ICH antenna and HF transmission components. The output power is about 100 kW around 30 MHz. Thomson 581 tetrode is used for the final amplifier whose cavity type is ground cathode. Overall gain is above 15 dB and the bandwidth is about 100 kHz

  1. Fabrication of the superferric cyclotron gas-stopper magnet at NSCL at Michigan state university

    International Nuclear Information System (INIS)

    Chouhan, S S; Bollen, G; DeKamp, J; Green, M A; Magsig, C; Zeller, A F; Lawton, D; Morrissey, D J; Ottarson, J; Schwarz, S

    2014-01-01

    The magnet for the cyclotron gas stopper is a newly designed, large warm-iron superconducting cyclotron sector gradient dipole. The maximum field in the centre (gap = 0.18 m) is 2.7 T. The outer diameter of magnet yoke is 4.0 m, with a pole radius of 1.1 m and B * ρ = 1.8 T m. The fabrication and assembly of the iron return yoke and twelve pole pieces is complete. Separate coils are mounted on the return yokes that have a total mass of about 167 metric tons of iron. This paper illustrates the design and the fabrication process for the cyclotron gas-stopper magnet that is being fabricated at MSU.

  2. A novel miniature superconducting converter for 1 kA magnets

    NARCIS (Netherlands)

    Chevtchenko, O.A.; Krooshoop, Hendrikus J.G.; ten Kate, Herman H.J.; Fedorovsky, Michael A.

    1996-01-01

    A miniature full-wave converter to control the current of a superconducting magnet is developed and tested in our institutes. Typical design values of the device are: AC voltage of 35 V, current of 7 A, and frequency 50-60 Hz; DC voltage o f f 0.2 V, and current of * 1 kA. An efficiency is better

  3. Heavy electron superconductivity: From 1K to 90K to ?

    International Nuclear Information System (INIS)

    Pethick, C.J.; Pines, D.

    1987-01-01

    This paper reviews the experimental results and physical arguments which led us to conclude that in heavy electron systems the physical mechanism responsible for superconductivity is an attractive interaction between the heavy electrons which results from the virtual exchange of antiferromagnetic f-electron moment fluctuations. In these systems, then, the superconductivity is of purely electronic origin; the phonon-induced interaction between electrons which leads to superconductivity in ordinary metals plays little or no role

  4. Design of the central region in the Warsaw K-160 cyclotron

    CERN Document Server

    Toprek, D; Choinski, J; Czosnyka, T

    2001-01-01

    This paper describes the design of the central region for h=2 and 3 modes of acceleration in the Warsaw K-160 cyclotron. The central region is unique and compatible with the two above-mentioned harmonic modes of operation. Only one spiral type inflector will be used. The electric field distribution in the inflector and in the four acceleration gaps has been numerically calculated from an electric potential map produced by the program RELAX3D. The geometry of the central region has been tested with the computations of orbits carried out by means of the computer code CYCLONE. The optical properties of the spiral inflector and the central region were studied by using the programs CASINO and CYCLONE, respectively.

  5. Design of the central region in the Warsaw K-160 cyclotron

    International Nuclear Information System (INIS)

    Toprek, D.; Sura, Josef; Choinski, Jaroslav; Czosnyka, Tomas

    2001-01-01

    This paper describes the design of the central region for h=2 and 3 modes of acceleration in the Warsaw K-160 cyclotron. The central region is unique and compatible with the two above-mentioned harmonic modes of operation. Only one spiral type inflector will be used. The electric field distribution in the inflector and in the four acceleration gaps has been numerically calculated from an electric potential map produced by the program RELAX3D. The geometry of the central region has been tested with the computations of orbits carried out by means of the computer code CYCLONE. The optical properties of the spiral inflector and the central region were studied by using the programs CASINO and CYCLONE, respectively

  6. A novel fast-scanning microwave heterodyne radiometer system for electron cyclotron emission measurements in the HT-7 superconducting tokamak

    International Nuclear Information System (INIS)

    Zhang, S.Y.; Wan, Y.X.; Xie, J.K.; Luo, J.R.; Li, J.G.; Kuang, G.L.; Gao, X.; Zhang, X.D.; Wan, B.N.; Wang, K.J.; Mao, J.S.; Gong, X.Z.; Qin, P.J.

    2000-01-01

    Two sets of fast-scanning microwave heterodyne radiometer receiver systems employing backward-wave oscillators in the 78-118 GHz and 118-178 GHz ranges were developed for electron cyclotron emission measurements (ECE) on the HT-7 superconducting tokamak. The double-sideband radiometer in the 78-118 GHz range measures 16 ECE frequency points with a scanning period of 0.65 ms. The novel design of the 2 mm fast-scanning heterodyne radiometer in the 118-178 GHz range enables the unique system to measure 48 ECE frequency points in 0.65 ms periodically. The plasma profile consistency in reproducible ohmic plasmas was used to relatively calibrate each channel by changing the toroidal magnetic field shot-by-shot. The absolute temperature value was obtained by a comparison with the results from the soft x-ray pulse height analysis measurements and Thomson scattering system. A preliminary temperature profile measurement result in pellet injection plasma is presented. (author)

  7. Electron cyclotron current drive experiments on DIII-D

    International Nuclear Information System (INIS)

    James, R.A.; Giruzzi, G.; Gentile, B. de; Rodriguez, L.; Fyaretdinov, A.; Gorelov, Yu.; Trukhin, V.; Harvey, R.; Lohr, J.; Luce, T.C.; Matsuda, K.; Politzer, P.; Prater, R.; Snider, R.; Janz, S.

    1990-05-01

    Electron Cyclotron Current Drive (ECCD) experiments on the DIII-D tokamak have been performed using 60 GHz waves launched from the high field side of the torus. Preliminary analysis indicates rf driven currents between 50 and 100 kA in discharges with total plasma currents between 200 and 500 kA. These are the first ECCD experiments with strong first pass absorption, localized deposition of the rf power, and τ E much longer than the slowing-down time of the rf generated current carriers. The experimentally measured profiles for T e , η e and Z eff are used as input for a 1D transport code and a multiply-ray, 3D ray tracing code. Comparisons with theory and assessment of the influence of the residual electric field, using a Fokker-Planck code, are in progress. The ECH power levels were between 1 and 1.5 MW with pulse lengths of about 500 msec. ECCD experiments worldwide are motivated by issues relating to the physics and technical advantages of the use of high frequency rf waves to drive localized currents. ECCD is accomplished by preferentially heating electrons moving in one toroidal direction, reducing their collisionality and thereby producing a non-inductively driven toroidal current. 6 refs., 4 figs

  8. Electron cyclotron current drive experiments on DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    James, R.A. (Lawrence Livermore National Lab., CA (USA)); Giruzzi, G.; Gentile, B. de; Rodriguez, L. (Association Euratom-CEA, Centre d' Etudes Nucleaires de Cadarache, 13 - Saint-Paul-les-Durance (France)); Fyaretdinov, A.; Gorelov, Yu.; Trukhin, V. (Kurchatov Inst. of Atomic Energy, Moscow (USSR)); Harvey, R.; Lohr, J.; Luce, T.C.; Matsuda, K.; Politzer, P.; Prater, R.; Snider, R. (General Atomics, San Di

    1990-05-01

    Electron Cyclotron Current Drive (ECCD) experiments on the DIII-D tokamak have been performed using 60 GHz waves launched from the high field side of the torus. Preliminary analysis indicates rf driven currents between 50 and 100 kA in discharges with total plasma currents between 200 and 500 kA. These are the first ECCD experiments with strong first pass absorption, localized deposition of the rf power, and {tau}{sub E} much longer than the slowing-down time of the rf generated current carriers. The experimentally measured profiles for T{sub e}, {eta}{sub e} and Z{sub eff} are used as input for a 1D transport code and a multiply-ray, 3D ray tracing code. Comparisons with theory and assessment of the influence of the residual electric field, using a Fokker-Planck code, are in progress. The ECH power levels were between 1 and 1.5 MW with pulse lengths of about 500 msec. ECCD experiments worldwide are motivated by issues relating to the physics and technical advantages of the use of high frequency rf waves to drive localized currents. ECCD is accomplished by preferentially heating electrons moving in one toroidal direction, reducing their collisionality and thereby producing a non-inductively driven toroidal current. 6 refs., 4 figs.

  9. Status report of the three phase 25 kA, 1.5 kW thermally switched superconducting rectifier, transformer and switches

    NARCIS (Netherlands)

    ten Kate, Herman H.J.; Holtslag, A.H.M.; Knoben, J.; Steffens, H.A.; van de Klundert, L.J.M.

    1983-01-01

    A 25 kA, 1.5 kW superconducting rectifier system has been developed. This rectifier system working like an a.c.-d.c, converter with a primary current of 35 A at 0.1Hz, will energize a 25 kA coil with an average power of 5.4 MJ/hr and a proposed energy efficiency of at least 96%. Such a highly

  10. High-power ion-cyclotron-resonance heating in the Wisconsin Levitated Octupole

    International Nuclear Information System (INIS)

    Fortgang, C.M.

    1983-05-01

    Ion cyclotron resonance heating has been investigated, both experimentally and theoretically, on the Wisconsin Levitated Octupole. Heating of both ions and electrons has been observed. Typically, a two component ion energy distribution is produced (300 eV and 50 eV) with the application of 500 kW of rf power into a 5 x 10 12 cm -3 density plasma. Power is coupled to the plasma with an antenna that also serves as the inductor of an oscillator tank circuit. The oscillator is tunable from 1 to 3 MHz and can be applied for periods up to 10 msec. The experiments were performed with hydrogen, gun injected plasmas

  11. Plasma Production and Heating in the Superconducting Levitron

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, O. A.; Birdsall, D. H.; Hartman, C. W.; Hooper, Jr., E. B.; Munger, R. H.; Taylor, C. E. [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1971-10-15

    Plasma production and heating in the Superconducting Levitron are described. The device has a floating superconducting ring with 40-cm major radius and 5-cm minor radius, which carries up to 600 kA current. Toroidal field is provided by a current of up to 1 MA. Six poloidal field coils are used to shape the magnetic surfaces to obtain field configurations with strong shear and with minimum average B, a local minimum -B well, or minimum {partial_derivative}B/{partial_derivative}s ({delta}B/B Less-Than-Or-Equivalent-To 0.005 - 0.05). Large area surfaces at liquid helium temperature which are not directly exposed to the plasma provide ultrahigh vacuum. Methods of production and heating of dense plasma with appreciable {beta} have been studied using a classical diffusion and thermal conduction model, which includes trapped-particle effects. Computations have been made both for heating by an initial hot electron plasma and for energetic neutral injection. The latter technique yields n Almost-Equal-To 10{sup 13} cm{sup -3}, T{sub e} Almost-Equal-To T{sub i} Almost-Equal-To 0.3 to 0.8 keV with existing sources (200 mA equivalent current at 2 keV). Production and heating by energetic electrons proceeds in two steps: First, a hot electron plasma with n Almost-Equal-To 10{sup 11} to 10{sup 13} cm{sup -3}, T{sub e}, hot Almost-Equal-To 100 to 500 keV is established by electron cyclotron resonance heating (ECRH). Second, dense plasma is formed by injection of a short pulse (50 {mu}s) of neutral gas. The inherent cutoff limit of direct ECRH is thereby overcome. Numerical computations of the subsequent in situ heating by energetic electrons predict T{sub i} = 0,14 to 2.0 keV, n = 5 x 10{sup 13} to 10{sup 14} cm{sup -3} for B{sub poloidal} = 1.5 to 6 kG. Thus, heating and ion temperatures comparable to or greater than obtained in the Tokamak T-3 device are predicted. This technique allows scaling to ignition temperature for a D-T plasma using available microwave power sources and

  12. An infrared free electron laser system for the proposed Chemical Dynamics Research Laboratory at LBL based on a 500 MHz superconducting linac

    International Nuclear Information System (INIS)

    Kim, K.J.; Byrns, R.; Chattopadhyay, S.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E.; Leemans, W.; Staples, J.; Taylor, B.; Xie, M.

    1992-09-01

    We describe a new design of the Infrared Free Electron Laser (IRFEL) for the proposed Chemical Dynamics Research Laboratory (CDRL) at LBL. The design and choice of parameters are dictated by the unique requirements of the CDRL scientific program. The accelerator system is based on the 500 MHz superconducting cavity technology to achieve a wavelength stability of 10 -4

  13. A superconducting RFQ for an ECR injector

    International Nuclear Information System (INIS)

    Ben-Zvi, I.

    1988-01-01

    The beam dynamics and resonator properties of a superconducting radio-frequency quadrupole (RFQ) for heavy ions are discussed. The motivation is its use as a very low velocity section following an electron cyclotron resonance (ECR) source for injection into a superconducting heavy-ion linac. The constraints on the design and performance of this accelerating structure are presented. Expressions for a limiting stable phase angle and longitudinal and transverse acceptance are derived. A numerical example is given, using the SUNYLAC linac at Sony Stony Brook. Beam-dynamics calculations with PARMTEQ are reported, verifying the theoretical beam-dynamics calculations. (author) 12 refs., 1 tab

  14. Cyclotron resonance spectroscopy of a high-mobility two-dimensional electron gas from 0.4 to 100 K at high filling factors

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Jeremy A. [Univ. of Alabama, Birmingham, AL (United States); Tokumoto, Takahisa [Univ. of Alabama, Birmingham, AL (United States); Cherian, Judy G. [Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab. (MagLab); Kuno, J. [Rice Univ., Houston, TX (United States); Reno, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); McGill, Stephen A. [Florida State Univ., Tallahassee, FL (United States). National High Magnetic Field Lab. (MagLab); Karaiskaj, Denis [Univ. of South Florida, Tampa, FL (United States); Hilton, David J. [Univ. of Alabama, Birmingham, AL (United States)

    2015-10-01

    We have studied the cyclotron mobility of a Landau-quantized two-dimensional electron gas as a function of temperature (0.4 --100 K) at a fixed magnetic field (1.25 T) using terahertz time-domain spectroscopy in a sample with a low frequency mobility of μdc = 3.6 x 106 cm2 V-1 s-1 and a carrier concentration of ns = 2 x 106 cm-2. The low temperature mobility in this sample results from both impurity scattering and acoustic deformation potential scattering, with μ$-1\\atop{CR}$ ≈ (2.1 x 105 cm2 V-1 s-1)-1 + (3.8 x 10-8 V sK-1 cm-2 x T)-1 at low temperatures. Above 50 K, the cyclotron oscillations show a strong reduction in both the oscillation amplitude and lifetime that is dominated by the contribution due to polar optical phonons. These results suggest that electron dephasing times as long as ~ 300 ps are possible even at this high lling factor (v = 6:6) in higher mobility samples (> 107 cm2 V-1 s-1) that have lower impurity concentrations and where the cyclotron mobility at this carrier concentration would be limited by acoustic deformation potential scattering.

  15. Cyclotron He++ implantations effect in superconductors YBa2Cu3O7-δ

    International Nuclear Information System (INIS)

    Santos, G.R. dos; Santos, J.C.R. dos; Morales, R.K.

    2001-01-01

    dry heated in an alumina crucible, with oxygen flux of 5.6 ml.s -1 a 1223K during 20 h. After pressing, we got the samples in pellets with 350 μm thickness and density 5.8 gcm -3 . The sintering was done in the same condition of the preparing for 18 hours, when the temperature was reduced (7.7 K.min -1 ) to 673 K and brought to room temperature. In that stage we took it out pallets, with mass around 5.86 mg, and size compatible with the probe for magnetic permeability measurements (2x1x1 mm). Irradiation Procedure - The samples were fixed, with metallic indium, in a water-cooled target holders made of copper. The indium was used for proper heat dissipation and as temperature controller during irradiation. In earlier works, X-ray diffraction and magnetic permeability measurements showing no changes due to indium adsorption or absorption. The irradiations were done at lEN's CV-28 Cyclotron. The '' particle beam with 28 MeV maximum energy was periodically degraded with a rotating disk with aluminum foils of different thickness. This way, it was possible a homogeneous ion implantation into the sample thickness. The typical currents were 500 nA, corresponding to a flux of 1.64x10 12 ''.cm -2 s -1 . Results - The magnetic permeability measurements were performed using a conventional system for zero detection ('Lock-in amplifier' 124 PAR). The temperature range was from 66 to 94 K. After irradiations it was observed structure's bump like, in the permeability curve. This bumps also showed changes in relative position in the curve, followed by changes in T c(onset) . This behavior suggests that changes in T c(onset) could be attributed to a defined amount of implanted ions. This hypothesis is justified considering that each bump is the register of a starting phase transformation, as consequence of the helium concentration. Although Maish had also observed similar structure in resistivity measurements as function of temperature, in YBaCuO irradiated with 63 MeV protons' 10 14

  16. Organic superconductivity

    International Nuclear Information System (INIS)

    Jerome, D.

    1980-01-01

    We present the experimental evidences for the existence of a superconducting state in the Quasi One Dimensional organic conductor (TMTSF) 2 PF 6 . Superconductivity occuring at 1 K under 12 kbar is characterized by a zero resistance diamagnetic state. The anistropy of the upper critical field of this type II superconductor is consistent with the band structure anistropy. We present evidences for the existence of large superconducting precursor effects giving rise to a dominant paraconductive contribution below 40 K. We also discuss the anomalously large pressure dependence of T sb(s), which drops to 0.19 K under 24 kbar in terms of the current theories. (author)

  17. Design and fabrication of a superconducting magnet for an 18 GHz electron cyclotron resonance ion∕photon source NFRI-ECRIPS.

    Science.gov (United States)

    You, H-J; Jang, S-W; Jung, Y-H; Lho, T-H; Lee, S-J

    2012-02-01

    A superconducting magnet was designed and fabricated for an 18 GHz ECR ion∕photon source, which will be installed at National Fusion Research Institute (NFRI) in South Korea. The magnetic system consists of a set of four superconducting coils for axial mirror field and 36 pieces of permanent magnets for hexapolar field. The superconducting coils with a cryocooler (1.5 W @ 4.2 K) allow one to reach peak mirror fields of 2.2 T in the injection and those of 1.5 T in the extraction regions on the source axis, and the resultant hexapolar field gives 1.35 T on the plasma chamber wall. The unbalanced magnetic force between the coils and surrounding yoke has been minimized to 16 ton by a coil arrangement and their electrical connection, and then was successfully suspended by 12 strong thermal insulating supports made of large numbers of carbon fibers. In order to block radiative thermal losses, multilayer thermal insulations are covered on the coil windings as well as 40-K aluminum thermal shield. Also new schemes of quench detection and safety system (coil divisions, quench detection coils, and heaters) were employed. For impregnation of the windings a special epoxy has been selected and treated to have a higher breaking strength and a higher thermal conductivity, which enables the superconductors to be uniformly and rapidly cooled down or heated during a quench.

  18. Superconductivity

    International Nuclear Information System (INIS)

    Andersen, N.H.; Mortensen, K.

    1988-12-01

    This report contains lecture notes of the basic lectures presented at the 1st Topsoee Summer School on Superconductivity held at Risoe National Laboratory, June 20-24, 1988. The following lecture notes are included: L.M. Falicov: 'Superconductivity: Phenomenology', A. Bohr and O. Ulfbeck: 'Quantal structure of superconductivity. Gauge angle', G. Aeppli: 'Muons, neutrons and superconductivity', N.F. Pedersen: 'The Josephson junction', C. Michel: 'Physicochemistry of high-T c superconductors', C. Laverick and J.K. Hulm: 'Manufacturing and application of superconducting wires', J. Clarke: 'SQUID concepts and systems'. (orig.) With 10 tabs., 128 figs., 219 refs

  19. Ion source and injection line for high intensity medical cyclotron

    Science.gov (United States)

    Jia, XianLu; Guan, Fengping; Yao, Hongjuan; Zhang, TianJue; Yang, Jianjun; Song, Guofang; Ge, Tao; Qin, Jiuchang

    2014-02-01

    A 14 MeV high intensity compact cyclotron, CYCIAE-14, was built at China Institute of Atomic Energy (CIAE). An injection system based on the external H- ion source was used on CYCIAE-14 so as to provide high intensity beam, while most positron emission tomography cyclotrons adopt internal ion source. A beam intensity of 100 μA/14 MeV was extracted from the cyclotron with a small multi-cusp H- ion source (CIAE-CH-I type) and a short injection line, which the H- ion source of 3 mA/25 keV H- beam with emittance of 0.3π mm mrad and the injection line of with only 1.2 m from the extraction of ion source to the medial plane of the cyclotron. To increase the extracted beam intensity of the cyclotron, a new ion source (CIAE-CH-II type) of 9.1 mA was used, with maximum of 500 μA was achieved from the cyclotron. The design and test results of the ion source and injection line optimized for high intensity acceleration will be given in this paper.

  20. Progress in research, April 1, 1992--March 31, 1993, Texas A and M University Cyclotron Institute

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-07-01

    This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported.

  1. Progress in research, April 1, 1992 - March 31, 1993, Texas A and M University Cyclotron Institute

    International Nuclear Information System (INIS)

    1993-07-01

    This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported

  2. Superconducting ECR ion source system

    International Nuclear Information System (INIS)

    Sharma, S.C.; Gore, J.A.; Gupta, A.K.; Saxena, A.

    2017-01-01

    In order to cover the entire mass range of the elements across the periodic table, an ECR based heavy ion accelerator programme, consisting of a superconducting ECR (Electron Cyclotron Resonance) source and a room temperature RFQ (Radio Frequency Quadrupole) followed by low and high beta superconducting resonator cavities has been proposed. The 18 GHz superconducting ECR ion source system has already been commissioned and being operated periodically at FOTIA beam hall. This source is capable of delivering ion beams right from proton to uranium with high currents and high charge states over a wide mass range (1/7 ≤ q/m ≤ 1/2) across the periodic table, including U"3"4"+ (q/m∼1/7) with 100 pna yield. The normalized transverse beam emittance from ECR source is expected to be <1.0 pi mm mrad. ECR ion sources are quite robust, making them suitable for operating for weeks continuously without any interruption

  3. Research and development of ion surfing RF carpets for the cyclotron gas stopper at the NSCL

    Energy Technology Data Exchange (ETDEWEB)

    Gehring, A.E. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87544 (United States); Brodeur, M. [University of Notre Dame, Notre Dame, IN (United States); Bollen, G.; Morrissey, D.J.; Schwarz, S. [National Superconducting Cyclotron Laboratory, Michigan State University, 640 S. Shaw Lane, East Lansing, MI 48824 (United States)

    2016-06-01

    A model device to transport thermal ions in the cyclotron gas stopper, a next-generation beam thermalization device under construction at the National Superconducting Cyclotron Laboratory, is presented. Radioactive ions produced by projectile fragmentation will come to rest at distances as large as 45 cm from the extraction orifice of the cyclotron gas stopper. The thermalized ions will be transported to the exit by RF carpets employing the recently developed “ion surfing” method. A quarter-circle prototype RF carpet was tested with potassium ions, and ion transport velocities as high as 60 m/s were observed over distances greater than 10 cm at a helium buffer gas pressure of 80 mbar. The transport of rubidium ions from an RF carpet to an electrode below was also demonstrated. The results of this study formed the basis of the design of the RF carpets for use in the cyclotron gas stopper.

  4. Ponderomotive force near cyclotron resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Mitsuo; Sanuki, Heiji

    1987-01-01

    The ponderomotive force, which is involved in the excitation of macroscopic behaviors of plasma caused by wave motion, plays an important role in various non-linear wave motion phenomena. In the present study, equations for the pondermotive force for plasma in a uniform magnetic field is derived using a renormalization theory which is based on the Vlasov equation. It is shown that the pondermotive force, which diverges at the cyclotron resonence point according to adiabatic approximation, can be expressed by a non-divergent equation by taking into account the instability of the cyclotron orbit due to high-order scattering caused by a wave. This is related with chaotic particle behaviors near cyclotron resonance, where the pondermotive force is small and the diffusion process prevails. It is assumed here that the amplitude of the high-frequency electric field is not large and that the broadening of cyclotron levels is smaller than the distance between the levels. A global chaos will be created if the amplitude of the electric field becomes greater to allow the broadening to exceed the distance between the levels. (Nogami, K.).

  5. Transient characteristics of parallel running of the 20kVA superconducting synchronous generator and a conventional one

    International Nuclear Information System (INIS)

    Nitta, T.; Okada, T.

    1989-01-01

    This paper describes electrical transient characteristics of parallel running of the 20kVA superconducting synchronous generator and a conventional one. In the experimental power system, the superconducting generator is connected through reactors (artificial transmission lines) to a regional power system (infinite bus) and the conventional generator (20kVA) is connected to the terminal of the superconducting generator. Several tests were performed in order to consider the transient behavior of superconducting generator (SCG) in the power system. The items of the tests are synchronous closing test, loss of synchronism test and disconnecting and reclosing test. From the experimental results, it can be said that by installing SCG in power systems, voltage stability and power system stability can be improved in transient states as well as in steady states and the variation of armature current of SCG during a transient period is extremely larger than that of the conventional one. The transient analysis by a computer simulation was also carried out for the experiments. The simulation results are in good agreement with the experimental ones

  6. Stereoscopic Planar Laser-Induced Fluorescence Imaging at 500 kHz

    Science.gov (United States)

    Medford, Taylor L.; Danehy, Paul M.; Jones, Stephen B.; Jiang, N.; Webster, M.; Lempert, Walter; Miller, J.; Meyer, T.

    2011-01-01

    A new measurement technique for obtaining time- and spatially-resolved image sequences in hypersonic flows is developed. Nitric-oxide planar laser-induced fluorescence (NO PLIF) has previously been used to investigate transition from laminar to turbulent flow in hypersonic boundary layers using both planar and volumetric imaging capabilities. Low flow rates of NO were typically seeded into the flow, minimally perturbing the flow. The volumetric imaging was performed at a measurement rate of 10 Hz using a thick planar laser sheet that excited NO fluorescence. The fluorescence was captured by a pair of cameras having slightly different views of the flow. Subsequent stereoscopic reconstruction of these images allowed the three-dimensional flow structures to be viewed. In the current paper, this approach has been extended to 50,000 times higher repetition rates. A laser operating at 500 kHz excites the seeded NO molecules, and a camera, synchronized with the laser and fitted with a beam-splitting assembly, acquires two separate images of the flow. The resulting stereoscopic images provide three-dimensional flow visualizations at 500 kHz for the first time. The 200 ns exposure time in each frame is fast enough to freeze the flow while the 500 kHz repetition rate is fast enough to time-resolve changes in the flow being studied. This method is applied to visualize the evolving hypersonic flow structures that propagate downstream of a discrete protuberance attached to a flat plate. The technique was demonstrated in the NASA Langley Research Center s 31-Inch Mach 10 Air Tunnel facility. Different tunnel Reynolds number conditions, NO flow rates and two different cylindrical protuberance heights were investigated. The location of the onset of flow unsteadiness, an indicator of transition, was observed to move downstream during the tunnel runs, coinciding with an increase in the model temperature.

  7. Modern high-temperature superconductivity

    International Nuclear Information System (INIS)

    Ching Wu Chu

    1988-01-01

    Ever since the discovery of superconductivity in 1911, its unusual scientific challenge and great technological potential have been recognized. For the past three-quarters of a century, superconductivity has done well on the science front. This is because sueprconductivity is interesting not only just in its own right but also in its ability to act as a probe to many exciting nonsuperconducting phenomena. For instance, it has continued to provide bases for vigorous activities in condensed matter science. Among the more recent examples are heavy-fermion systems and organic superconductors. During this same period of time, superconductivity has also performed admirably in the applied area. Many ideas have been conceived and tested, making use of the unique characteristics of superconductivity - zero resistivity, quantum interference phenomena, and the Meissner effect. In fact, it was not until late January 1987 that it became possible to achieve superconductivity with the mere use of liquid nitrogen - which is plentiful, cheap, efficient, and easy to handle - following the discovery of supercondictivity above 90 K in Y-Ba-Cu-O, the first genuine quaternary superconductor. Superconductivity above 90 K poses scientific and technological challenges not previously encountered: no existing theories can adequately describe superconductivity above 40 K and no known techniques can economically process the materials for full-scale applications. In this paper, therefore, the author recalls a few events leading to the discovery of the new class of quaternary compounds with a superconducting transition temperature T c in the 90 K range, describes the current experimental status of high-temperature superconductivity and, finally, discusses the prospect of very-high-temperature superconductivity, i.e., with a T c substantially higher than 100 K. 97 refs., 7 figs

  8. Ion cyclotron system design for KSTAR tokamak

    International Nuclear Information System (INIS)

    Hong, B. G.; Hwang, C. K.; Jeong, S. H.; Yoony, J. S.; Bae, Y. D.; Kwak, J. G.; Ju, M. H.

    1998-05-01

    The KSTAR (Korean Superconducting Tokamak Advanced Research) tokamak (R=1.8 m, a=0.5 m, k=2, b=3.5T, I=2MA, t=300 s) is being constructed to do long-pulse, high-b, advanced-operating-mode fusion physics experiments. The ion cyclotron (IC) system (in conjunction with an 8-MW neutral beam and a 1.5-MW lower hybrid system) will provide heating and current drive capability for the machine. The IC system will deliver 6 MW of RF power to the plasma in the 25 to 60 MHz frequency range, using a single four-strap antenna mounted in a midplane port. It will be used for ion heating, fast-wave current drive (FWCD), and mode-conversion current drive (MCCD). The phasing between current straps in the antenna will be adjustable quickly during operation to provide the capability of changing the current-drive efficiency. This report describes the design of the IC system hardware: the electrical characteristics of the antenna and the matching system, the requirements on the power sources, and electrical analyses of the launcher. (author). 7 refs., 2 tabs., 40 figs

  9. Ion cyclotron system design for KSTAR tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Hong, B. G.; Hwang, C. K.; Jeong, S. H.; Yoony, J. S.; Bae, Y. D.; Kwak, J. G.; Ju, M. H

    1998-05-01

    The KSTAR (Korean Superconducting Tokamak Advanced Research) tokamak (R=1.8 m, a=0.5 m, k=2, b=3.5T, I=2MA, t=300 s) is being constructed to do long-pulse, high-b, advanced-operating-mode fusion physics experiments. The ion cyclotron (IC) system (in conjunction with an 8-MW neutral beam and a 1.5-MW lower hybrid system) will provide heating and current drive capability for the machine. The IC system will deliver 6 MW of RF power to the plasma in the 25 to 60 MHz frequency range, using a single four-strap antenna mounted in a midplane port. It will be used for ion heating, fast-wave current drive (FWCD), and mode-conversion current drive (MCCD). The phasing between current straps in the antenna will be adjustable quickly during operation to provide the capability of changing the current-drive efficiency. This report describes the design of the IC system hardware: the electrical characteristics of the antenna and the matching system, the requirements on the power sources, and electrical analyses of the launcher. (author). 7 refs., 2 tabs., 40 figs.

  10. Probabilitas Tegangan Sentuh Dan Tegangan Langkah Di Lokasi Rencana Gardu Induk 500 kV Antosari

    Directory of Open Access Journals (Sweden)

    Abdul Latif

    2016-06-01

    Full Text Available Semakin berkembangnya pertindustrian di Indonesia, maka kebutuhan daya listrik yang dibutuhkan semakin meningkat. Untuk memenuhi kebutuhan daya listrik tersebut pada tahun 2016, PT PLN (Persero merencanakan pembangunan GITET 500 kV Antosari. Pembangunan GITET 500 kV Antosari merupakan tindak lanjut dari rencana PT PLN (Persero yang akan menambah pasokan energi listrik ke Bali melalui sistem interkoneksi Jawa – Bali menggunakan jaringan transmisi SUTET 500 kV, dimulai dari GITET 500 kV Paiton dan akan sampai di GITET 500 kV Antosari. Untuk mengamankan gardu induk dari ancaman sambaran petir, salah satu cara yang digunakan adalah dengan mengamankan sistem perntanahan dilokasi gardu induk. Maka dipilih sistem pentanahan grid di lokasi rencana pembangunan Gardu Induk 500 kV Antosari. Penelitian dilakukan untuk menganalisis perbandingan ukuran luas pentanahan dengan kedalaman batang konduktor terhadap tahanan pentanahan grid, tegangan sentuh, tegangan langkah dan probabilitas timbulnya tegangan sentuh dan tegangan langkah. Data tahanan tanah yang didapatkan dari pengukuran secara langsung digunakan untuk mengetahui  nilai tahanan jenis tanah kemudian digunakan untuk menghitung tahanan pentanahan grid, tegangan sentuh, tegangan langkah dan probabilitas tegangan sentuh dan tegangan langkah. Perhitungan tahanan pentanahan grid menggunakan persamaan IEEE, Standard 80-2000 sedangkan untuk perhitungan tegangan sentuh dan tegangan langkah menggunakan IEEE, Standard 665-1995. Berdasarkan hasil penelitian di lokasi gardu induk untuk kondisi tanah basah dengan luas grid 3 m x 3 m dan kedalaman 5 m didapatkan nilai tahanan pentanahan grid 0,49 ohm dan nilai tegangan langkah 125 volt dengan probabilitas 0,72%. Sedangkan untuk kondisi tanah kering dengan luas grid 3 m x 3m dan kedalaman 5 didapatkan nilai tahanan pentanahan grid 1,11 ohm dan nilai tegangan langkah 281 volt dengan probabilitas 0,72%. Dari hasil analisis juga menunjukan dengan luas grid 3 m x 3

  11. Electromechanical characterization of superconducting wires and tapes at 77 K

    CERN Document Server

    Bjoerstad, Roger

    The strain dependency of the critical current in state-of-the-art cuprate high-temperature superconductors (HTS) has been characterized. A universal test machine (UTM) combined with a critical current measurement system has been used to characterize the mechanical and the superconducting properties of conductors immersed in an open liquid nitrogen dewar. A set-up has been developed in order to perform simultaneous measurements of the superconductor lattice parameter changes, critical current, as well as the stress and strain at 77 K in self-field in a high energy synchrotron beamline. The HTS tapes and wires studied were based on YBCO, Bi-2223 and Bi-2212. The YBCO tapes were produced by SuperPower and American Superconductors (AMSC). Two types of Bi-2223 tapes, HT and G, were produced by Sumitomo Electric Industries (SEI). The Bi-2212 wires were produced by Oxford Superconducting Technology (OST) using Nexans granulate precursor, before undergoing a specialized over pressure (OP) processing and heat treatmen...

  12. 10 GHz ECRIS for Warsaw Cyclotron

    CERN Document Server

    Sudlitz, K

    1999-01-01

    Cusp type, 10 GHz ECRIS has been built and tested earlier. For obtaining intensive beams, more relevant for cyclotron, cusp geometry has been replaced by hexapole. Discharge chamber (stainless steel, 50 mm diameter, 250 mm long) is an extension of a coaxial line, feeding RF (9,6 GHz, up to 200 W) to the plasma. The NdFeB hexapole (0,52 T on the surface) has been used. The axial magnetic field is created by water cooled coils. The axial injection line dedicated to K160 isochronous heavy ion cyclotron has been constructed. The line consists of Glaser lenses, double focusing magnet, solenoid and mirror type inflector. The system provides sufficient transmission of the beam from ECR ion source to the firsts orbits of the cyclotron for m/q ranging from 7 to 2. After successful initial tests which were done in July 1997 the ECRIS serves as an external source for Warsaw Cyclotron.

  13. Recent Progress in Power Refrigeration below 2 K for Superconducting Accelerators

    CERN Document Server

    Claudet, Serge

    2005-01-01

    As a result of technico-economical optimization and quest for increased performance, 2 K cryogenics is now present in large accelerator projects using superconducting magnets or acceleration cavities. Consequently, large cryogenic systems producing refrigeration capacity below 2 K in the kW range and with high efficiency over a large dynamic range are needed. After CEBAF and SNS, this is the case for the Large Hadron Collider (LHC) project at CERN for which eight 2.4 kW @ 1.8 K refrigeration units are needed to cool each a 3.3 km long sector of high-field magnets. Combining cold hydrodynamic compressors in series with warm volumetric compressors, complete pre-series units as well as sets of series cold compressors have been intensively tested and validated from two different industrial suppliers. After recalling the possible 2 K refrigeration cycles and their comparative merits, this paper describes the specific features of the LHC system and presents the achieved performance with emphasis on the progress in...

  14. Removal of particles by ICRF cleaning in HT-7 superconducting tokamak

    International Nuclear Information System (INIS)

    Hu Jiansheng; Li Jiangang; Zhang Shouyin; Gu Xuemao; Zhang Xiaodong; Zhao Yanping; Gong Xianzu; Kuang Guangli; Li Chengfu; Luo Jiarong; Wang Xiaoming; Gao Xiang; Wan Baonian; Xie Jikang; Wan Yuanxi

    2001-01-01

    The ICRF (Ion Cyclotron Range Frequency) cleaning technique has been used as a routine wall cleaning method in the HT-7 superconducting tokamak. In a wide range of toroidal field, the removal rate of residual gas by ICRF cleaning was about twenty times higher than that of glow discharge cleaning (GDC). At different gas pressure and RF power levels, the ICRF cleaning is studied carefully. A good impurity cleaning effect and a very high hydrogen removal rate were obtained. The removal rate of hydrogen by 5 kW ICRF cleaning achieved was 1.6 x 10 -5 Torr.l/s. And the relationships among pressure P, outgassing rate Q, atomic layers L absorbed on surface and the cleaning mode were discussed briefly

  15. Impedance matching network systems using stub-lines of 20 kW CW RF amplifier for SKKUCY-9 compact cyclotron

    International Nuclear Information System (INIS)

    Lee, Seung Hyun; Song, Ho Seung; Kim, Jeong Hwan; Cong, Truong Van; Kim, Hui Su; Yeon, Yeong Heum; Lee, Yong seok; Chai, Jong Seo

    2015-01-01

    The SKKUCY-9 is a compact cyclotron for radioactive isotopes (RI) production of positron emission tomography (PET). Charged particles such as H-ions are accelerated azimuthally within a high intensity electric field (E-field) generated from a radio frequency (RF) system in cyclotron. A high power RF signal is transmitted from an RF amplifier to an RF resonating cavity. The RF system of the SKKUCY-9 operates in continuous wave (CW) mode. If an ion beam were accelerated in the cyclotron, the vacuum level and permittivity would be changed because of beam loading. It causes an impedance shift of the RF resonating cavity. This impedance mismatch generates reflected power that decreases the RF transmitting power. To prevent this situation, an impedance matching system is necessary. This paper describes the impedance matching system of a 20 kW RF amplifier in an SKKUCY-9 compact cyclotron. The impedance matching circuit was designed using both an input stage and output stage, which are divided between the cathode and anode in a vacuum tube that is used as an amplifying device. The equivalent circuit of the matching system is made of passive elements. The characteristic results of designed circuit were calculated using a Smith chart. In assembling, the inductors were replaced by movable stub-line structures. The dimensions of the stub-line structures were optimized with equations and the measurement results. The experiment was performed to find the result values of matching circuit impedance and RF power amplitude

  16. Quench propagation in the superconducting 6 kA flexible busbars of the LHC

    International Nuclear Information System (INIS)

    Herzog, R.; Calvi, M.; Sonnemann, F.; Pelegrin-Carcelen, J.M.

    2002-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components

  17. Quench Propagation in the Superconducting 6 kA Flexible Busbars of the LHC

    CERN Document Server

    Calvi, M; Pelegrin-Carcelen, J M; Sonnemann, F

    2002-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit c...

  18. Quench propagation in the superconducting 6 kA flexible busbars of the LHC

    Science.gov (United States)

    Herzog, R.; Calvi, M.; Sonnemann, F.; Pelegrin-Carcelen, J. M.

    2002-05-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components.

  19. Micro gas turbine thermodynamic and economic analysis up to 500 kWe size

    International Nuclear Information System (INIS)

    Galanti, Leandro; Massardo, Aristide F.

    2011-01-01

    Highlights: → Thermoeconomic analysis and optimization of micro gas turbines up to 500 kWe. → Analysis carried out for both regenerative and intercooled regenerative cycles. → Focus on thermodynamic, geometric and cost parameters of the main MGT devices. → ICR cycle has an interesting reduction in capital and electricity costs, rising size. → Complete thermoeconomic investigation is essential to support thermodynamic analysis. -- Abstract: In this paper a thermoeconomic analysis and optimization of micro gas turbines (MGT) up to 500 kWe is presented. This analysis is strongly related to the need of minimizing specific capital cost, still high for MGT large market penetration, and optimizing MGT size to match market needs. The analysis was carried out for both existing regenerative MGT cycles and new inter-cooled regenerative cycles, using the Web-based ThermoEconomic Modular Program by the University of Genoa. The attention is mainly focused on the basis of thermodynamic, geometric and capital cost parameters of the main MGT devices (such as recuperator size, material and effectiveness, turbine inlet temperature, and compressor pressure ratio) and on economic scenario (fuel cost, cost of electricity, etc.) for different MGT size in the range 25-500 kWe.

  20. Fast wave and electron cyclotron current drive in the DIII-D tokamak

    International Nuclear Information System (INIS)

    Petty, C.C.; Pinsker, R.I.; Austin, M.E.

    1995-01-01

    The non-inductive current drive from directional fast Alfven and electron cyclotron waves was measured in the DIII-D tokamak in order to demonstrate these forms of radiofrequency (RF) current drive and to compare the measured efficiencies with theoretical expectations. The fast wave frequency was 8 times the deuterium cyclotron frequency at the plasma centre, while the electron cyclotron wave was at twice the electron cyclotron frequency. Complete non-inductive current drive was achieved using a combination of fast wave current drive (FWCD) and electron cyclotron current drive (ECCD) in discharges for which the total plasma current was inductively ramped down from 400 to 170 kA. For steady current discharges, an analysis of the loop voltage revealed up to 195 kA of a non-inductive current (out of 310 kA) during combined electron cyclotron and fast wave injection, with a maximum of 110 kA of FWCD and 80 kA of ECCD achieved (not simultaneously). The peakedness of the current profile increased with RF current drive, indicating that the driven current was centrally localized. The FWCD efficiency increased linearly with the central electron temperature as expected; however, the FWCD was severely degraded in low current discharges owing to incomplete fast wave absorption. The measured FWCD agreed with the predictions of a ray tracing code only when a parasitic loss of 4% per pass was included in the modelling along with multiple pass absorption. Enhancement of the second harmonic ECCD efficiency by the toroidal electric field was observed experimentally. The measured ECCD was in good agreement with Fokker-Planck code predictions. (author). 41 refs, 13 figs, 1 tab

  1. Calculation of proton beam initial orbit at cyclotron central region

    International Nuclear Information System (INIS)

    Pramudita Anggraita

    2012-01-01

    A calculation of proton beam initial orbits at cyclotron central region was carried out using Scilab 5.2.0. The calculation was done in 2 dimensions in a homogeneous magnetic field of 1.66 tesla at frequency of fourth harmonics. The positions of ion source, dees, and dummy dees follow those of GE Minitrace cyclotron, peak dee voltage 30 kV. The calculation yields result comparable to those simulated at KIRAMS-13 cyclotron. (author)

  2. Broadband electron spin resonance from 500 MHz to 40 GHz using superconducting coplanar waveguides

    Science.gov (United States)

    Clauss, Conrad; Bothner, Daniel; Koelle, Dieter; Kleiner, Reinhold; Bogani, Lapo; Scheffler, Marc; Dressel, Martin

    2013-04-01

    We present non-conventional electron spin resonance (ESR) experiments based on microfabricated superconducting Nb thin film waveguides. A very broad frequency range, from 0.5 to 40 GHz, becomes accessible at low temperatures down to 1.6 K and in magnetic fields up to 1.4 T. This allows for an accurate inspection of the ESR absorption position in the frequency domain, in contrast to the more common observation as a function of magnetic field. We demonstrate the applicability of frequency-swept ESR on Cr3+ atoms in ruby as well as on organic radicals of the nitronyl-nitroxide family. Measurements between 1.6 and 30 K reveal a small frequency shift of the ESR and a resonance broadening below the critical temperature of Nb, which we both attribute to a modification of the magnetic field configuration due to the appearance of shielding supercurrents in the waveguide.

  3. Design and development of power supplies at VECC for accelerators

    International Nuclear Information System (INIS)

    Thakur, S.K.

    2013-01-01

    Several power supplies have been designed and developed in-house incorporating various topologies to match the load requirements. Most of the power supplies have been being utilised in K-130 and K-500 cyclotrons operation successfully from last several years. Amongst other types, Switching Mode PS (SMPS), Phase Controlled Rectifier (PCR), Linear mode power supply are mostly in use, irrespective of their own merits and demerits. Switching mode power supply (SMPS) is most common topology for various applications ranging from high current to high voltage applications. Due to low stored energy and faster response, the SMPS incorporating Pulse Switch Modulation (PSM) configuration is most suitable for high voltage DC power supply at larger power compared to its counterparts, makes possible to operate the power system without crowbar. For an IOT cathode power supply, a 200kW at - 40kV High voltage power supply is under development incorporating SMPS and PSM technique. Earlier, High Voltage power supply was made by using Tetrode Tube in linear mode for RF amplifier for K-130 Cyclotron. Later, in K-500 Cyclotron, a High Voltage power supply was developed incorporating PCR topology rated at 20kV, 20 Amp for Anodes for 3 nos. of RF amplifiers. These HV power supply is equipped with ultra-fast acting Crowbar Protection System developed in VECC which is for the protection of costly RF Tubes against the internal arc. Design and development of SMPS based Bipolar Power Supply with 4-Quadrant operation rated at ± 27 V, ± 300 Amp with current stability around 100 ppm for Super-conducting Magnets along with quench protection and energy dumping scheme. (author)

  4. Superconducting transition and low-field magnetoresistance of a niobium single crystal at 4.2 deg. K

    International Nuclear Information System (INIS)

    Perriot, G.

    1967-01-01

    We report the study of the electrical resistance of a niobium single crystal, at 4.2 deg. K, from the beginning of the superconductive transition to 80 kilo oersteds. Critical fieldsH c2 and H c3 have been determined. Influences on superconductive transition of current density, field-current angle, crystal orientation and magnetoresistance have been studied. Variation laws of low-field transverse and longitudinal magneto-resistances have been determined. (author) [fr

  5. Programs on large scale applications of superconductivity in Japan

    International Nuclear Information System (INIS)

    Yasukochi, K.; Ogasawara, T.

    1974-01-01

    History of the large scale application of superconductivity in Japan is reported. Experimental works on superconducting magnet systems for high energy physics have just begun. The programs are described by dividing into five categories: 1) MHD power generation systems, 2) superconducting rotating machines, 3) cryogenic power transmission systems, 4) magnetically levitated transportation, and 5) application to high energy physics experiments. The development of a big superconducting magnet for a 1,000 kW class generator was set up as a target of first seven year plan, which came to end in 1972, and continues for three years with the budget of 900 million yen from 1973 on. In the second phase plan, a prototype MHD generator is argued. A plan is contemplated to develop a synchronous generator with inner rotating field by Fuji Electric Co. The total budget for the future plans of superconducting power transmission system amounts to 20 billion yen for the first period of 8 approximately 9 years. In JNR's research and development efforts, several characteristic points are picked up: 1) linear motor drive with active side on ground, 2) loop track, 3) combined test run of maglev and LSM. The field test at the speed of 500 km/hr on a 7 km track is scheduled to be performed in 1975. The target of operation is in 1985. A 12 GeV proton synchrotron is now under construction for the study on high energy physics. Three ring intersecting storage accelerator is discussed for future plan. (Iwakiri, K.)

  6. Potential use of superconducting magnets for neutron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Duthil, R; Kircher, F; Lottin, J C; Palanque, S [CEA/Saclay, 91 - Gif-sur-Yvette (France); Aucouturier, J; Fache, P [DT, CGR MeV, 78 Buc (France)

    1984-01-01

    The results of a feasibility study on the use of superconducting magnets for neutron therapy devices will be reported. Two possibilities can be foreseen: - SC magnets used in the isocentric primary beam transport line. The advantage is to increase the energy of the particles which can be transported (up to 70 MeV for protons), compared to existing systems, with a lower weight. This solution could be used very quickly. - A SC isocentric cyclotron, working at on average field of 4.7 T for accelerating deuterons up to 30 MeV. The feasibility of such a machine is fairly established but technical developments are needed, mainly in view of the rotation and of the miniaturisation of the cyclotron.

  7. Superconducting Ferromagnetic Nanodiamond.

    Science.gov (United States)

    Zhang, Gufei; Samuely, Tomas; Xu, Zheng; Jochum, Johanna K; Volodin, Alexander; Zhou, Shengqiang; May, Paul W; Onufriienko, Oleksandr; Kačmarčík, Jozef; Steele, Julian A; Li, Jun; Vanacken, Johan; Vacík, Jiri; Szabó, Pavol; Yuan, Haifeng; Roeffaers, Maarten B J; Cerbu, Dorin; Samuely, Peter; Hofkens, Johan; Moshchalkov, Victor V

    2017-06-27

    Superconductivity and ferromagnetism are two mutually antagonistic states in condensed matter. Research on the interplay between these two competing orderings sheds light not only on the cause of various quantum phenomena in strongly correlated systems but also on the general mechanism of superconductivity. Here we report on the observation of the electronic entanglement between superconducting and ferromagnetic states in hydrogenated boron-doped nanodiamond films, which have a superconducting transition temperature T c ∼ 3 K and a Curie temperature T Curie > 400 K. In spite of the high T Curie , our nanodiamond films demonstrate a decrease in the temperature dependence of magnetization below 100 K, in correspondence to an increase in the temperature dependence of resistivity. These anomalous magnetic and electrical transport properties reveal the presence of an intriguing precursor phase, in which spin fluctuations intervene as a result of the interplay between the two antagonistic states. Furthermore, the observations of high-temperature ferromagnetism, giant positive magnetoresistance, and anomalous Hall effect bring attention to the potential applications of our superconducting ferromagnetic nanodiamond films in magnetoelectronics, spintronics, and magnetic field sensing.

  8. Design of 500kW grate fired test facility using CFD

    DEFF Research Database (Denmark)

    Rosendahl, Lasse Aistrup; Kær, Søren Knudsen; Jørgensen, K.

    2005-01-01

    A 500kW vibrating grate fired test facility for solid biomass fuels has been designed using numerical models including CFD. The CFD modelling has focussed on the nozzle layout and flowpatterns in the lower part of the furnace, and the results have established confidence in the chosen design...

  9. Academic training: Applied superconductivity

    CERN Multimedia

    2007-01-01

    LECTURE SERIES 17, 18, 19 January from 11.00 to 12.00 hrs Council Room, Bldg 503 Applied Superconductivity : Theory, superconducting Materials and applications E. PALMIERI/INFN, Padova, Italy When hearing about persistent currents recirculating for several years in a superconducting loop without any appreciable decay, one realizes that we are dealing with a phenomenon which in nature is the closest known to the perpetual motion. Zero resistivity and perfect diamagnetism in Mercury at 4.2 K, the breakthrough during 75 years of several hundreds of superconducting materials, the revolution of the "liquid Nitrogen superconductivity"; the discovery of still a binary compound becoming superconducting at 40 K and the subsequent re-exploration of the already known superconducting materials: Nature discloses drop by drop its intimate secrets and nobody can exclude that the last final surprise must still come. After an overview of phenomenology and basic theory of superconductivity, the lectures for this a...

  10. Superconducting snake with the field of 75 kGs for the VEPP-2M electron-positron storage ring

    International Nuclear Information System (INIS)

    Anashin, V.V.; Vasserman, I.B.; Vlasov, A.M.

    1985-01-01

    Superconducting ''snake'' with the field of 75 kG is established in the VEPP-2M electron-positron storage ring for increase of colliding beam luminosity up to 2x10 31 cmsup(-2)sdup(-1) in the energy range from 2x200 to 2x700 MeV. The ''snake'' comprises three central magnets with the field of 75 kG and two side ones with the field of 45 kG and it is placed in one of rectilinear experimental gaps. Description of design peculiarities of the ''snake'' and its parameters are given. Parameters of beams with switched on and switched off ''snake'' as well as parameters of coils and superconducting wire are presented

  11. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Milton, B.F.; Dawson, R.; Erdman, K.L.

    1989-05-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. TRIUMF is cooperating with a local industrial company in designing and constructing such a cyclotron. It will be a four sector H - cyclotron, exploiting the newly developed high brightness multicusp ion source. This source with H - current capability in excess of 5 mA makes feasible accelerated H - beam intensities of up to 500 μA. Beam extraction is by stripping to H + in a thin graphite foil. Extraction of two high-intensity beams, with energy variable from 15 to 30 MeV is planned. The use of an external ion source, provision of a good vacuum in the acceleration region, and the careful choice of materials for components in the median plane leads to a cyclotron that will have low activation and can be easily serviced in spite of the very high operating beam intensities. A design extension to 70 MeV using many of the design features of the 30 MeV cyclotron can be easily made. Such a machine with a good quality variable energy beam is a highly desirable source of protons for isotope production, injection into higher energy high intensity acceleration, injection into higher energy high intensity accelerators, and as an irradiation facility for ocular melanomas. Design of the 30 MeV cyclotron is well advanced and construction is in progress

  12. Reversal of the Upper Critical Field Anisotropy and Spin-Locked Superconductivity in K2Cr3As3

    International Nuclear Information System (INIS)

    Balakirev, Fedor Fedorovich; Kong, T.; Jaime, Marcelo; McDonald, Ross David; Mielke, Charles H.; Gurevich, A.; Canfield, P. C.; Bud'ko, S. L.

    2016-01-01

    Recently, superconductivity in K 2 Cr 3 As 3 (T c =6.1 K) was discovered. The crystalline lattice contains an array of weakly coupled, double well [(Cr 3 As 3 ) 2- ] ∞ linkages stretched along the c axis, suggesting the possibility of quasi-one-dimensional superconductivity. Moderately anisotropic upper critical field was revealed in single crystals, with very large initial slopes, dH || c2 /dT=12 T/K along the Cr chains and dH perpendicular c2 /dT =7 T/K perpendicular to the chains. Given the ambiguity of conclusions based on the extrapolations of H c2 (T) measured near T c to low temperatures, we performed high-field measurements of H c2 (T) on K 2 Cr 3 As 3 single crystals in pulsed magnetic fields which enabled us to reveal the full anisotropic H c2 (T) curves from T c down to 600 mK.

  13. The state of superconductivity

    International Nuclear Information System (INIS)

    Clark, T.D.

    1981-01-01

    The present status of applications based on the phenomena of superconductivity are reviewed. Superconducting materials, large scale applications, the Josephson effect and its applications, and superconductivity in instrumentation, are considered. The influence that superconductivity has had on modern theories of elementary particles, such as gauge symmetry breaking, is discussed. (U.K.)

  14. Hydrostatic Pressure Study on 3-K Phase Superconductivity in Sr2RuO4-Ru Eutectic Crystals by AC Magnetic Susceptibility Measurements

    International Nuclear Information System (INIS)

    Yaguchi, Hiroshi; Watanabe, Hiromichi; Sakaue, Akira

    2012-01-01

    We have investigated the effect of hydrostatic pressure on 3-K phase superconductivity in Sr 2 RuO 4 -Ru eutectic crystals by means of AC magnetic susceptibility measurements. We have found that the application of hydrostatic pressure suppresses the superconducting transition temperature T c of the 3-K phase with a pressure coefficient of dT c /dP ≈ −0.2 K/GPa, similar to the case of the 1.5-K phase. We have also observed that the effect of hydrostatic pressure on the 3-K phase seems to be elastic whilst that of uniaxial pressure is plastic.

  15. Coupling of structure to magnetic and superconducting orders in quasi-one-dimensional K2Cr3As3

    Science.gov (United States)

    Taddei, K. M.; Zheng, Q.; Sefat, A. S.; de la Cruz, C.

    2017-11-01

    Quasi-one-dimensional A2Cr3As3 (with A =K , Cs, Rb) is an intriguing new family of superconductors which exhibit many similar features to the cuprate and iron-based unconventional superconductor families. Yet, in contrast to these systems, no charge or magnetic ordering has been observed which could provide the electronic correlations presumed necessary for an unconventional superconducting pairing mechanism—an absence which defies predictions of first-principles models. We report the results of neutron scattering experiments on polycrystalline K2Cr3As3 (Tc˜7 K ) which probed the low-temperature dynamics near Tc. Neutron diffraction data evidence a subtle response of the nuclear lattice to the onset of superconductivity while inelastic scattering reveals a highly dispersive column of intensity at the commensurate wave vector q =(00 1/2 ) which loses intensity beneath Tc—indicative of short-range magnetic fluctuations. Using linear spin-wave theory, we model the observed scattering and suggest a possible structure to the short-range magnetic order. These observations suggest that K2Cr3As3 is in close proximity to a magnetic instability and that the incipient magnetic order both couples strongly to the lattice and competes with superconductivity, in direct analogy with the iron-based superconductors.

  16. California-Oregon 500-kV transmission line development of design criteria

    International Nuclear Information System (INIS)

    Simpson, K.D.

    1990-01-01

    The California-Oregon Transmission Project (COTP) encompassed the design and construction of a third 500-kV ac intertie between California and the Pacific Northwest Transmission system. Sargent ampersand Lundy's (S ampersand L) scope of work in the COTP includes the design of approximately 150 miles of new single-circuit, 500-kV transmission line from southern Oregon to the vicinity of Redding, California. This paper presents the development of the design criteria for this segment of the project, which crosses diverse topographic and climatic regions. This project is an example of the increasing utilization of computers in transmission line engineering. Almost all aspects of design involved the use of the computer. Also, the development of the design criteria for this project coincided with an early release of the TLWorkstation software package by EPRI. TLWorkstation is an engineering workstation containing a family of programs for various aspects of transmission line design. This engineering software allows for increasing refinement in the design and economic optimization of transmission lines and is becoming an important design tool for transmission engineers

  17. PIXE analysis by baby cyclotron

    International Nuclear Information System (INIS)

    Yoshida, Hyogo; Tanaka, Teruaki; Ito, Takashi; Toda, Yohjiro; Wakasa, Hideichiro

    1988-01-01

    The Japan Steel Works, Ltd. has been supplying a very small sized cyclotron (Baby Cyclotron) to hospitals and research facilities. The cyclotron is designed to produce short-lived radioisotopes for medical use. In the present study, this cyclotron is modified so that it can serve for PIXE analysis. The PIXE (particle induced X-ray emission) technique has the following features: (1) Down to 1 ng of trace material in a sample (mg - μg) can be detected, (2) An analysis run is completed in one to ten minutes, permitting economical analysis for a large number of samples, (3) Several elements can be analyzed simultaneously, with an almost constant sensitivity for a variety of elements ranging from aluminum to heavy metals, (4) Analysis can be performed nondestructively without a chemical process, and (5) The use of microbeam can provide data on the distribution of elements with a resolution of several μm. Software for analysis is developed to allow the modified equipment to perform peak search, background fitting, and identification and determination of peaks. A study is now being conducted to examine the performance of the equipment for PIXE analysis of thin samples. Satisfactory results have been obtained. The analysis time, excluding the background correction, is 5-10 min. (Nogami, K.)

  18. Superconductivity and transport properties in LaRu4Sb12 single crystals probed by radiation-induced disordering

    International Nuclear Information System (INIS)

    Goshchitskii, B.; Naumov, S.; Kostromitina, N.; Karkin, A.

    2007-01-01

    Resistivity ρ(T) and Hall coefficient R H (T) in magnetic fields H up to 14 T were studied in superconducting (T c = 3.3 K) LaRu 4 Sb 12 single crystals disordered by fast neutron irradiation. Atomic disordering leads to increase in residual resistivity ρ 0 , decrease of Hall number and suppression of superconductivity. The upper critical field slope -dH c2 /dT increases approximately linear with ρ 0 . The irradiation effects are almost recovered after annealing at 500 deg. C. The observed radiation-induced effects in LaRu 4 Sb 12 are compared with those in PrOs 4 Sb 12 in terms of unconventional mechanisms of superconductivity

  19. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Baartman, R.; Kleevan, W.J.; Laxdal, R.E.; Milton, B.F.; Otter, A.J.; Pearson, J.B.; Poirier, R.L.; Schmor, P.W.; Schneider, H.R.; Erdman, K.L.; Walker, Q.

    1989-01-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. We describe such a cyclotron currently under construction. It is a 30 MeV H - design that exploits a newly developed high brightness multicusp ion source which is capable of H - currents of up to 5 mA. This together with careful beam matching then makes feasible accelerated H - beam intensities of 500 μA. The cyclotron being built is a four sector radial ridge design with two 45 degree dees in opposite valleys. Beam extraction is by stripping to H + in a thin graphite foil. Two extraction probes will allow simultaneous extraction of two beams, each with an intensity of up to 200 μA. Energy variation from 15 MeV to 30 MeV is achieved by varying the radial position of the extraction foil. 7 refs., 4 figs., 1 tab

  20. U-2g0 cyclotron operational experience and improvement

    International Nuclear Information System (INIS)

    Gigal, B.N.; Gul'bekyan, G.G.; Kozlov, S.I.; Oganesyan, R.Ts.

    1983-01-01

    Brief description of main syste's of the U-200 isochronous 2-m cyclotron put into opera ion in 1968 is given and its operational characteristics a e presented. The cyclotron is used for conducting inve tigations in the field of nuclear physics. Ions from d uterium to argon have been accelerated in the cyclotro'. Annual time of target irradiation constitutes 2000-4000. The specific features of the cyclotron are: high l vel of a magnetic field (of about 20 kOe), possibili y of acceleration of ions with different mass-to-charge ratio a low correcting winding power, simple and high-e fective beam extraction by the method of charge exchange on a thin target allowing to vary smoothly energy of extracted ons. An experience in the U-200 cyclotron development and o eration is used as the basis for designing and choosing basic parameters of the U-200P, U-250, U-400 heavy ion cyclotrons

  1. RIA Superconducting Drift Tube Linac R and D

    International Nuclear Information System (INIS)

    Popielarski, J.; Bierwagen, J.; Bricker, S.; Compton, C.; DeLauter, J.; Glennon, P.; Grimm, T.; Hartung, W.; Harvell, D.; Hodek, M.; Johnson, M.; Marti, F.; Miller, P.; Moblo, A.; Norton, D.; Popielarski, L.; Wlodarczak, J.; York, R.C.; Zeller, A.

    2009-01-01

    Cavity and cryomodule development work for a superconducting ion linac has been underway for several years at the National Superconducting Cyclotron Laboratory. The original application of the work was the proposed Rare Isotope Accelerator. At present, the work is being continued for use with the Facility for Rare Isotope Beams (FRIB). The baseline linac for FRIB requires 4 types of superconducting cavities to cover the velocity range needed to accelerate an ion beam to (ge) 200 MeV/u: 2 types of quarter-wave resonator (QWR) and 2 types of half-wave resonator (HWR). Superconducting solenoids are used for focusing. Active and passive shielding is required to ensure that the solenoids field does not degrade the cavity performance. First prototypes of both QWR types and one HWR type have been fabricated and tested. A prototype solenoid has been procured and tested. A test cryomodule has been fabricated and tested. The test cryomodule contains one QWR, one HWR, one solenoid, and one super-ferric quadrupole. This report covers the design, fabrication, and testing of this cryomodule

  2. Cyclotron-based neutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K. [Sumitomo Heavy Industries, Ltd (Japan); Tanaka, H.; Sakurai, Y.; Maruhashi, A. [Kyoto University Research Reactor Institute (Japan)

    2013-04-19

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation and treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8 Multiplication-Sign 109 neutrons/cm{sup 2}/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with {sup 10}B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  3. Superconduction at 77 K

    International Nuclear Information System (INIS)

    Mueller, H.G.

    1989-01-01

    This general paper deals with the advantages which may result from the use of ceramic high-temperature superconductors. The use of these new superconductors for generators and electric motors for ship propulsion is regarded as a promising potential defense application. Furthermore, SMES (Superconducting Magnetic Energy Storage) can be used as a 'power compressor' for future high-performance weapon systems such as electromagnetic cannons, high-energy lasers, and high power microwaves. (MM) [de

  4. ECR ion source for variable energy cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Bose, D K; Taki, G S; Nabhiraj, P Y; Pal, G; Dasgupta, B; Mallik, C; Das, S K; Bandopadhaya, D K; Bhandari, R K [Variable Energy Cyclotron Centre, Calcutta (India)

    1995-09-01

    Some performance characteristics of 6.4 GHz two stage ECR ion source which was under development at this centre is presented. The present ion source will facilitate acceleration of light heavy ions with the existing k=130 variable energy cyclotron. Multiply charged heavy ion (MCHI) beam from the source will also be utilized for atomic physics studies. Oxygen beam has already been used for ion implantation studies. The external injection system under development is nearing completion. Heavy ion beam from cyclotron is expected by end of 1995. (author).

  5. Superconductivity at the industrial scale

    International Nuclear Information System (INIS)

    Tixador, P.; Lebrun, Ph.

    2011-01-01

    The discovery of superconductivity is 100 years old but theoretical works are still necessary: the BCS theory does not apply to the new families of high temperature superconducting materials discovered after 1986. In 2001 it was discovered that MgB 2 is superconducting at 39 K, this critical temperature is not the highest but MgB 2 is easy to produce and cheap. Today's highest critical temperature under atmospheric pressure is that of the HgTlBaCaCuO compound: 138 K. The complexity and the cost of cryogenic systems restrain the applications of superconductivity. The author reviews the applications of superconducting in medical imaging, particle detectors, and in the safety systems of power networks. (A.C.)

  6. Application of differential-and-Lie-algebraic techniques to the orbit dynamics of cyclotrons

    International Nuclear Information System (INIS)

    Davies, W.G.; Douglas, S.R.; Pusch, G.D.; Lee-Whiting, G.E.

    1991-01-01

    A new orbit-dynamics code, DACYC, is being developed for the TASCC superconducting cyclotron. DACYC makes use of differential algebra and Lie Algebra to calculate and analyze partial, one-and/or multi-turn maps to very high order. Accurate, three-dimensional, analytic models of the magnetic and RF fields are used, which satisfy Maxwell's equations exactly. The maps can be analyzed with normal-form methods or to produce linear or high-order phase-space plots

  7. Superconductivity: Is there a problem in transuranics?

    International Nuclear Information System (INIS)

    Colineau, Eric; Griveau, Jean-Christophe; Eloirdi, Rachel; Hen, Amir; Caciuffo, Roberto

    2014-01-01

    Superconductivity was first reported in 1942 for uranium metal (¡-U) and in 1958 for U compounds: UCo, U6Mn, U6Fe, and U6Co, with critical temperatures Tc, of 1.7, 2.3, 3.9, and 2.3K, respectively. A new class of U superconductors emerged in the early 1980’s with the discovery of U heavy fermion superconductors : UBe13 (Tc = 0.85K), UPt3 (Tc = 0.53K), URu2Si2 (Tc = 1.5K) , UPd2Al3 (Tc = 1.9K) … Furthermore, in most of these systems, the superconducting phases coexist with antiferromagnetic (AF) correlations which have characteristic temperatures, usually the Néel temperature TN, that are typically one order of magnitude greater than the corresponding superconducting critical temperatures Tc. Superconductivity was even shown to co-exist with ferromagnetism in e.g. UGe2 (Tc ï» 0.8K, TC ï» 30K at p ï» 1.2GPa) and URhGe (Tc = 0.25K, TC = 9.5K). Heavy fermion superconductors still remain a major challenge for condensed matter physics. The existence of heavy fermion superconductivity and its coexistence or proximity with magnetic order suggests that the conventional mechanism of phonon-mediated superconductivity is inappropriate and that alternative mechanisms, like spin fluctuations, should be considered for Cooper pairing

  8. Properties of the TRIUMF cyclotron beam

    International Nuclear Information System (INIS)

    Craddock, M.K.; Blackmore, E.W.; Dutto, G.; Kost, C.J.; Mackenzie, G.H.; Richardson, J.R.; Root, L.W.; Schmor, P.

    1975-08-01

    Eight percent of the 300 keV d.c. beam from the ion source can be transmitted to 500 MeV in the TRIUMF cyclotron, without using the buncher. The beam losses are entirely accounted for; there are no significant losses due to orbit dynamic problems during 1500 turns of acceleration. The phase history is in good agreement with predictions based on the magnetic field survey. The effect of the harmonic coils and injection parameters on beam quality has been investigated. (author)

  9. PXIe based data acquisition and control system for ECRH systems on SST-1 and Aditya tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Jatinkumar J., E-mail: jatin@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar (India); Shukla, B.K.; Rajanbabu, N.; Patel, H.; Dhorajiya, P.; Purohit, D. [Institute for Plasma Research, Bhat, Gandhinagar (India); Mankadiya, K. [Optimized Solutions Pvt. Ltd (India)

    2016-11-15

    Highlights: • Data Aquisition and control system (DAQ). • PXIe hardware–(PXI–PCI bus extension for Instrumention Express). • RHVPS–Regulated High Voltage Power supply. • SST1–Steady state superconducting tokamak. - Abstract: In Steady State Superconducting (SST-1) tokamak, various RF heating sub-systems are used for plasma heating experiments. In SST-1, Two Electron Cyclotron Resonance Heating (ECRH) systems have been installed for pre-ionization, heating and current drive experiments. The 42 GHz gyrotron based ECRH system is installed and in operation with SST-1 plasma experiments. The 82.6 GHz gyrotron delivers 200 kW CW power (1000 s) while the 42 GHz gyrotron delivers 500 kW power for 500 ms duration. Each gyrotron system consists of various auxiliary power supplies, the crowbar unit and the water cooling system. The PXIe (PCI bus extension for Instrumentation Express)bus based DAC (Data Acquisition and Control) system has been designed, developed and under implementation for safe and reliable operation of the gyrotron. The Control and Monitoring Software applications have been developed using NI LabView 2014 software with real time support on windows platform.

  10. PXIe based data acquisition and control system for ECRH systems on SST-1 and Aditya tokamak

    International Nuclear Information System (INIS)

    Patel, Jatinkumar J.; Shukla, B.K.; Rajanbabu, N.; Patel, H.; Dhorajiya, P.; Purohit, D.; Mankadiya, K.

    2016-01-01

    Highlights: • Data Aquisition and control system (DAQ). • PXIe hardware–(PXI–PCI bus extension for Instrumention Express). • RHVPS–Regulated High Voltage Power supply. • SST1–Steady state superconducting tokamak. - Abstract: In Steady State Superconducting (SST-1) tokamak, various RF heating sub-systems are used for plasma heating experiments. In SST-1, Two Electron Cyclotron Resonance Heating (ECRH) systems have been installed for pre-ionization, heating and current drive experiments. The 42 GHz gyrotron based ECRH system is installed and in operation with SST-1 plasma experiments. The 82.6 GHz gyrotron delivers 200 kW CW power (1000 s) while the 42 GHz gyrotron delivers 500 kW power for 500 ms duration. Each gyrotron system consists of various auxiliary power supplies, the crowbar unit and the water cooling system. The PXIe (PCI bus extension for Instrumentation Express)bus based DAC (Data Acquisition and Control) system has been designed, developed and under implementation for safe and reliable operation of the gyrotron. The Control and Monitoring Software applications have been developed using NI LabView 2014 software with real time support on windows platform.

  11. Superconductivity in borides and carbides

    International Nuclear Information System (INIS)

    Muranaka, Takahiro

    2007-01-01

    It was thought that intermetallic superconductors do not exhibit superconductivity at temperatures over 30 K because of the Bardeen-Cooper-Schrieffer (BCS) limit; therefore, researchers have been interested in high-T c cuprates. Our group discovered high-T c superconductivity in MgB 2 at 39 K in 2001. This discovery has initiated a substantial interest in the potential of high-T c superconductivity in intermetallic compounds that include 'light' elements (borides, carbides, etc.). (author)

  12. Characteristic K-shell x-ray production by protons below 500 keV

    International Nuclear Information System (INIS)

    Wheeler, R.M.; Chaturvedi, R.P.; Zander, A.R.

    1974-01-01

    The total thick target yield of K-shell x-rays produced in Ni by incident protons over the energy range 90 to 415 keV was measured. Similar measurements with 130 to 415 keV protons were made for Ti, Mn, Fe, Cu, and Zn. The East Texas State University 150 keV Cockcroft--Walton accelerator was used to study Ni K-shell x-rays produced by 90 to 150 keV protons. The remaining data were taken with the SUNY College at Cortland 400 keV Van de Graaff generator. The characteristic x-rays were measured with high resolution Si(Li) detectors. Using the most recent values of K-shell fluorescent yields, x-ray ionization cross sections were calculated and compared to theoretical predictions based on the binary encounter approximation (BEA) model. It was found that even though the data were lower than those expected by the BEA theory, they lie on a universal curve. A comprehensive summary of x-ray ionization cross section references covering the proton energy range up to 500 keV is also included. Possible applications of low energy accelerators (E/sub p/ less than or equal to 500 keV) for further experimental work is discussed

  13. First experimental observation of cyclotron superradiance

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, N S; Zotova, I V; Sergeev, A S; Konoplev, I V [Russian Academy of Sciences, Nizhny Novgorod (Russian Federation). Inst. of Applied Physics; Shpak, V G; Yalandin, M I; Shunajlov, C A; Ulmaskulov, M P [Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Electrophysics

    1997-12-31

    The first experimental observation of cyclotron superradiance from subnanosecond high-current electron bunches moving through waveguide systems is reported. Ultrashort microwave K{sub {alpha}} band pulses with a power of 200 kW and duration less than 0.5 ns were observed in the regime of group synchronism when the electron bunch drift velocity coincided with the group velocity of the electromagnetic waves. (author). 2 figs., 13 refs.

  14. Design considerations for superconducting magnets as a maglev pad

    International Nuclear Information System (INIS)

    Ichikawa, H.; Ogiwara, H.

    1974-01-01

    The design and construction of a thin superconducting magnet for a magnetically suspended high-speed train are explained. The superconducting magnet, which is to be used in a null-flux maglev train system, is called a 'wing-type' superconducting magnet because of its geometry. The wing-type superconducting magnet is about 1.5m long and weighs about 500kg, but its heat loss is within 1W, which is very small compared with that of conventional superconducting magnets. (author)

  15. Focusing and bunching of ion beam in axial injection channel of IPHC cyclotron TR24

    Science.gov (United States)

    Adam, T.; Ivanenko, I.; Kazarinov, N.; Osswald, F.; Traykov, E.

    2017-07-01

    The CYRCe cyclotron (CYclotron pour la ReCherche et l’Enseignement) is used at IPHC (Institut Pluridisciplinaire Hubert Curien) for the production of radio-isotopes for diagnostics, medical treatments and fundamental research in radiobiology. The TR24 cyclotron produced and commercialized by ACSI (Canada) delivers a 16-25 MeV proton beam with intensity from few nA up to 500 μA. The solenoidal focusing instead of existing quadrupole one is proposed in this report. The changing of the focusing elements will give the better beam matching with the acceptance of the spiral inflector of the cyclotron. The parameters of the focusing solenoid are found. Additionally, the main parameters of the bunching system are evaluated in the presence of the beam space charge. This system consists of the buncher installed in the axial injection beam line of the cyclotron. The using of the grid-less multi harmonic buncher may increase the accelerated beam current and will give the opportunity to new proton beam applications.

  16. Ion Cyclotron Heating on Proto-MPEX

    Science.gov (United States)

    Goulding, R. H.; Caughman, J. B. O.; Rapp, J.; Biewer, T. M.; Campbell, I. H.; Caneses, J. F.; Kafle, N.; Ray, H. B.; Showers, M. A.; Piotrowicz, P. A.

    2016-10-01

    Ion cyclotron heating will be used on Proto-MPEX (Prototype Material Plasma Exposure eXperiment) to increase heat flux to the target, to produce varying ion energies without substrate biasing, and to vary the extent of the magnetic pre-sheath for the case of a tilted target. A 25 cm long, 9 cm diameter dual half-turn helical ion cyclotron antenna has been installed in the device located at the magnetic field maximum. It couples power to ions via single pass damping of the slow wave at the fundamental resonance, and operates with ω 0.8ωci at the antenna location. It is designed to operate at power levels up to 30 kW, with a later 200 kW upgrade planned. Near term experiments include measuring RF loading at low power as a function of frequency and antenna gap. The plasma is generated by a helicon plasma source that has achieved ne > 5 ×1019m-3 operating with deuterium, as measured downstream from the ion cyclotron antenna location. Measurements will be compared with 1-D and 2-D models of RF coupling. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  17. A 1 T, 0.33 m bore superconducting magnet operating with cryocoolers at 12 K

    NARCIS (Netherlands)

    van der Laan, M.T.G.; van der Laan, M.T.G.; Tax, R.B.; ten Kate, Herman H.J.; van de Klundert, L.J.M.

    1992-01-01

    The application of small cryocoolers to cooling a superconducting magnet at 12 K has important advantages, especially for small and medium-size magnets. Simple construction and a helium-free magnet system were obtained. The demonstration magnet developed is a six-coil system with a volume of 75 L

  18. Superconducting materials

    International Nuclear Information System (INIS)

    Kormann, R.; Loiseau, R.; Marcilhac, B.

    1989-01-01

    The invention concerns superconducting ceramics containing essentially barium, calcium and copper fluorinated oxides with close offset and onset temperatures around 97 K and 100 K and containing neither Y nor rare earth [fr

  19. Field Demonstration of a 24-kV Superconducting Cable at Detroit Edison

    International Nuclear Information System (INIS)

    Kelley, Nathan; Corsaro, Pietro

    2004-01-01

    Customer acceptance of high temperature superconducting (HTS) cable technology requires a substantial field demonstration illustrating both the system's technical capabilities and its suitability for installation and operation within the utility environment. In this project, the world's first underground installation of an HTS cable using existing ductwork, a 120 meter demonstration cable circuit was designed and installed between the 24 kV bus distribution bus and a 120 kV-24 kV transformer at Detroit Edison's Frisbie substation. The system incorporated cables, accessories, a refrigeration system, and control instrumentation. Although the system was never put in operation because of problems with leaks in the cryostat, the project significantly advanced the state-of-the-art in the design and implementation of Warm Dielectric cable systems in substation applications. Lessons learned in this project are already being incorporated in several ongoing demonstration projects

  20. Studies on a Q/A selector for the SECRAL electron cyclotron resonance ion source.

    Science.gov (United States)

    Yang, Y; Sun, L T; Feng, Y C; Fang, X; Lu, W; Zhang, W H; Cao, Y; Zhang, X Z; Zhao, H W

    2014-08-01

    Electron cyclotron resonance ion sources are widely used in heavy ion accelerators in the world because they are capable of producing high current beams of highly charged ions. However, the design of the Q/A selector system for these devices is challenging, because it must have a sufficient ion resolution while controlling the beam emittance growth. Moreover, this system has to be matched for a wide range of ion beam species with different intensities. In this paper, research on the Q/A selector system at the SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) platform both in experiment and simulation is presented. Based on this study, a new Q/A selector system has been designed for SECRAL II. The features of the new design including beam simulations are also presented.

  1. Biomedical research with cyclotron produced radionuclides. Progress report, October 1, 1977--September 30, 1978

    International Nuclear Information System (INIS)

    Laughlin, J.S.; Benua, R.S.; Tilbury, R.S.; Bigler, R.E.

    1978-01-01

    Progress is reported on biomedical studies using cyclotron-produced 18 F, 15 O, 11 C, 13 N, 52 Fe, 38 K, 206 Bi, 73 Se, 53 Co, and 43 K. The following research projects are described: tumor detection and diagnosis; neurological studies; radiopharmaceutical development; 38 K as an indicator of blood flow to the myocardium; dosimetry for internally deposited isotopes in animals and man; cyclotron development; positron tomographic imaging with the TOKIM System; and review of positron emission transaxial tomograph instruments

  2. Proton induced changes of the texturing degree of superconducting YBaCuO ceramics

    International Nuclear Information System (INIS)

    Kalanov, M.U.

    2004-01-01

    Full text: The aim of this work was to improve conducting properties of superconducting yttrium ceramics by means of proton-induced increase in the texturing degree. The object were single-phase (98 %), isotropic YBa 2 Cu 3 O 7-δ (δ ≅ 0.05) ceramic pellets of 12 mm in diameter and 0.6 mm of thickness, with the average grain size of 14 μm, the lattice parameters a r ≅ 3.822, b r ≅ 3.883 and c r ≅ 11.673 A, the density ∼ 5.1 g.cm -3 , the specific resistance ∼ 3 mΩ· cm in the normal state, had the superconducting T c ≅ 91 K. The samples were irradiated at the cyclotron U-150 of the INP AS RUz with 18 MeV-protons within the range of fluences 1014 - 10 15 cm -2 at the beam current of 20 nA and 300 K. The structure characteristics of samples were determined at the diffractometer DRON-UM1 (λ CuKα 1.54178 A). Electrophysical parameters were measured with the four-probe technique at the direct current of 10 mA. The texturing degree was determined by the formula F t = P t - P o /1 - P o , where P o and P t are the ratios of the (00L) reflection intensity sum to that of all (HKL) structure lines for isotropic and textured ceramics, respectively. The diffraction spectrum of the sample irradiated with the proton fluence of 2·10 14 cm -2 demonstrated a noticeable decrease in the {HKL} reflection intensities and simultaneous increase in those of {00L}. By this the value of ρ (100 K) decreased in 3 times, and the T c by 0.3 K, the superconducting transition broadened and the resistivity slope of the temperature dependence increased. Further growth of the {{00L} line intensities at elevated doses (4·10 14 † 8·10 14 cm -2 ) did not occur, yet the ρ (100 K) value rose fast, the T c dropped, and the character of conductivity changed from metallic to semiconducting. Such anomaly in the structure characteristics and superconducting properties of the irradiated YBa 2 Cu 3 O 7-δ ceramics can be explained by formation of the texture on the sample surface

  3. ESCAR superconducting magnet system

    International Nuclear Information System (INIS)

    Gilbert, W.S.; Meuser, R.B.; Pope, W.L.; Green, M.A.

    1975-01-01

    Twenty-four superconducting dipoles, each about 1 meter long, provide the guide field for the Experimental Superconducting Accelerator Ring proton accelerator--storage ring. Injection of 50 MeV protons corresponds to a 3 kG central dipole field, and a peak proton energy of 4.2 GeV corresponds to a 46 kG central field. Thirty-two quadrupoles provide focusing. The 56 superconducting magnets are contained in 40 cryostats that are cryogenically connected in a novel series ''weir'' arrangement. A single 1500 W refrigeration plant is required. Design and testing of the magnet and cryostat system are described. (U.S.)

  4. Gas breakdown at cyclotron resonance with a submillimeter laser

    International Nuclear Information System (INIS)

    Hacker, M.P.; Temkin, R.J.; Lax, B.

    1976-01-01

    A pulsed 496-μm CH 3 F laser is used to produce gas breakdown in He at pressures between 1 and 300 Torr in an intense longitudinal magnetic field. Breakdown is detected by the observation of visible light when the electron cyclotron frequency (eB/m) equals the laser frequency, which occurs at B=216 kG for lambda=496 μm. At the lowest helium pressures and near cyclotron resonance, the focused laser intensity of 40 kW/cm 2 gives rise to very large electron heating rates, well beyond the limit of validity of conventional equilibrium breakdown theory. The observed result is an intensity-dependent resonant linewidth, much larger than predicted by equilibrium theories

  5. Superconducting nanowire single photon detectors fabricated from an amorphous Mo0.75Ge0.25 thin film

    International Nuclear Information System (INIS)

    Verma, V. B.; Lita, A. E.; Vissers, M. R.; Marsili, F.; Pappas, D. P.; Mirin, R. P.; Nam, S. W.

    2014-01-01

    We present the characteristics of superconducting nanowire single photon detectors (SNSPDs) fabricated from amorphous Mo 0.75 Ge 0.25 thin-films. Fabricated devices show a saturation of the internal detection efficiency at temperatures below 1 K, with system dark count rates below 500 cps. Operation in a closed-cycle cryocooler at 2.5 K is possible with system detection efficiencies exceeding 20% for SNSPDs which have not been optimized for high detection efficiency. Jitter is observed to vary between 69 ps at 250 mK and 187 ps at 2.5 K using room temperature amplifiers.

  6. Development of 6.6 kV/600 A superconducting fault current limiter using coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Yazawa, T., E-mail: takashi.yazawa@toshiba.co.j [Toshiba Corporation, Power Systems Company (Japan); Koyanagi, K.; Takahashi, M.; Toba, K.; Takigami, H.; Urata, M. [Toshiba Corporation, Power Systems Company (Japan); Iijima, Y.; Saitoh, T. [Fujikura Ltd. (Japan); Amemiya, N. [Superconductivity Research Laboratory, ISTEC (Japan); Shiohara, Y. [Department of Electrical Engineering, Kyoto University (Japan); Ito, T. [Tokyo Gas Co., Ltd. (Japan)

    2009-10-15

    As one of the programs in the Ministry of Economy, Trade and Industry (METI) project regarding R and D on superconducting coated conductor, three-phase superconducting fault current limiter (SFCL) for 6.6 kV application was developed and successfully tested. The developed SFCL was mainly comprised three-phase set of current limiting coils installed in a sub-cooled nitrogen cryostat with a GM cryocooler, circuit breakers and a sequence circuit. The whole system was installed in a cubicle. Two tapes of coated conductor were wound in parallel in each coil to obtain the rated current of 72 A rms. After developing the whole SFCL system, short circuit experiments were implemented with a short circuit generator. In a three-line ground fault test, the SFCL successfully restricted the prospected short circuit current over 1.6 kA to about 800 A by the applied voltage of 6.6 kV. The SFCL was installed in a user field and connected with a gas engine generator, followed by a consecutive operation. In this program, 600 A class FCL coil, with which four coated conductor tapes were wound, was also developed. The coil showed sufficiently low AC loss at the rated current. With these results, the program attained the planned target of the fundamentals for the 6.6 kV/600 A SFCL.

  7. Manufacturing on the radiopharmaceuticals produced by cyclotron

    International Nuclear Information System (INIS)

    Ueda, Nobuo

    1994-01-01

    Radiopharmaceutical (RP) produced by cyclotrons are widely used for the in vivo diagnosis of various diseases such as cancer, cerebral vascular disorders and cardiac diseases. The nuclides used as RPs and their nuclear reactions, and the quantity of RPs supplied in Japan in the last five years are shown. These RPs are delivered to about 1,100 hospitals in Japan. Thallium-201 and iodine-123 showed very high growth rate. Recently, two new I-123 RPs, BMIPP and MIBG which are heart-imaging agents, have been supplied. It suggests that the quantity of I-123 will increase much more in future. The image diagnostic method using RPs is called in vivo nuclear medicine, and has become the indispensable means for medical institutions together with X-ray CT, nuclear magnetic resonance imaging and ultrasonic diagnosis. The RPs for in vivo diagnosis generally used at present are classified into those labeled with the RIs produced with cyclotrons and those labeled with Tc-99m formed by the decay of Mo-99. The quantity being used is overwhelmingly more in the latter, but the former shows the tendency of growth. The commercial production of cyclotron RIs for medical use, the chemical forms and the diagnostic purposes of the RPs using cyclotron RIs, and the state of use of the cyclotron-produced RPs are reported. (K.I.)

  8. Study and field verification of the effects of removing closing resistors from 500 kV circuit breakers

    International Nuclear Information System (INIS)

    Selin, D.A.; Agrawal, B.L.; Farmer, R.G.; Demcko, J.A.

    1992-01-01

    Closing resistors in EHV circuit breakers are frequently used to reduce switching transients on lines thus preventing flashovers during line energization. Maintenance and failures of such closing resistors can be costly and reduce transmission system reliability. For these reasons, APS conducted an investigation into the technical feasibility of operating its 500 kV without closing resistors. This paper describes study results of removing closing resistors from 500 kV breakers in a system which employs older technology silicon carbide type surge arresters. The paper also describes results of field tests of the expected flashover rates calculated in the study. These field tests involve repeatedly energizing a 258 mile 500 kV line using a breaker in which the closing resistors are disabled. Transient overvoltages captured during the tests are compared with predicted overvoltages. The study concludes that closing resistors may be removed from the subject system without unacceptable consequences

  9. Molybdenum-rhenium superconducting suspended nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Mohsin; Christopher Hudson, David; Russo, Saverio [Centre for Graphene Science, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom)

    2014-06-09

    Suspended superconducting nanostructures of MoRe 50%/50% by weight are fabricated employing commonly used fabrication steps in micro- and nano-meter scale devices followed by wet-etching with Hydro-fluoric acid of a SiO{sub 2} sacrificial layer. Suspended superconducting channels as narrow as 50 nm and length 3 μm have a critical temperature of ≈6.5 K, which can increase by 0.5 K upon annealing at 400 °C. A detailed study of the dependence of the superconducting critical current and critical temperature upon annealing and in devices with different channel widths reveals that desorption of contaminants is responsible for the improved superconducting properties. These findings pave the way for the development of superconducting electromechanical devices using standard fabrication techniques.

  10. Superconductivity application technologies. Superconducting quadrupole magnet and cooling system for KEK B factory

    International Nuclear Information System (INIS)

    Tsuchiya, Kiyosumi; Yamaguchi, Kiyoshi; Sakurabata, Hiroaki; Seido, Masahiro; Matsumoto, Kozo.

    1997-01-01

    At present in National Laboratory for High Energy Physics (KEK), the construction of B factory is in progress. By colliding 8 GeV electrons and 3.5 GeV positrons, this facility generates large amounts of B mesons and anti-B mesons, and performs the elementary particle experiment of high accuracy. It is the collision type accelerator of asymmetric two-ring type comprising 8 GeV and 3.5 GeV rings. In the field of high energy physics, superconductivity technology has been put to practical use. As the objects of superconductivity technology, there are dipole magnet for bending beam, quadrupole magnet for adjusting beam, large solenoid magnet used for detector and so on. Superconducting magnets which are indispensable for high energy, superconducting wire material suitable to accelerators, and the liquid helium cooling system for maintaining superconducting magnets at 4.4 K are reported. The technologies of metallic conductors and making their coils have advanced rapidly, and also cooling technology has advanced, accordingly, superconductivity technology has reached the stage of practical use perfectly. (K.I.)

  11. Sample of superconducting wiring (Niobium Titanium)

    CERN Multimedia

    About NbTi cable: The cable consists of 36 strands of superconducting wire, each strand has a diameter of 0.825 mm and houses 6300 superconducting filaments of niobium-titanium (Nb-Ti, a superconducting alloy). Each filament has a diameter of about 0.006 mm, i.e. 10 times smaller than a typical human hair. The filaments are embedded in a high-purity copper matrix. Copper is a normal conducting material. The filaments are in the superconductive state when the temperature is below about -263ºC (10.15 K). When the filaments leave the superconductive state, the copper acts as conductor transports the electrical current. Each strand of The NbTi cable (at superconducting state) has a current density of up to above 2000 A/mm2 at 9 T and -271ºC (2.15 K). A cable transport a current of about 13000 A at 10 T and -271ºC (2.15 K). About LHC superconducting wiring: The high magnetic fields needed for the LHC can only be reached using superconductors. At very low temperatures, superconductors have no electrical resistan...

  12. Sample of superconducting wiring (Niobium Titanium)

    CERN Multimedia

    About NbTi cable: The cable consists of 36 strands of superconducting wire, each strand has a diameter of 0.825 mm and houses 6300 superconducting filaments of niobium-titanium (Nb-Ti, a superconducting alloy). Each filament has a diameter of about 0.006 mm, i.e. 10 times smaller than a typical human hair. The filaments are embedded in a high-purity copper matrix. Copper is a normal conducting material. The filaments are in the superconductive state when the temperature is below about -263ºC (10.15 K). When the filaments leave the superconductive state, the copper acts as conductor transports the electrical current. Each strand of The NbTi cable (at superconducting state) has a current density of up to above 2000 A/mm2 at 9 T and -271ºC (2.15 K). A cable transport a current of about 13000 A at 10 T and -271ºC (2.15 K). About LHC superconducting wiring: The high magnetic fields needed for the LHC can only be reached using superconductors. At very low temperatures, superconductors have no electrical resista...

  13. Conceptual design study of the K-DEMO magnet system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Keeman, E-mail: kkeeman@nfri.re.kr [National Fusion Research Institute, 169-148 Gwahak-ro, Daejeon 305-806 (Korea, Republic of); Oh, Sangjun; Park, Jong Sung; Lee, Chulhee; Im, Kihak; Kim, Hyung Chan; Lee, Gyung-Su [National Fusion Research Institute, 169-148 Gwahak-ro, Daejeon 305-806 (Korea, Republic of); Neilson, George; Brown, Thomas; Kessel, Charles; Titus, Peter; Zhai, Yuhu [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States)

    2015-10-15

    Highlights: • Perform a preliminary conceptual study for a steady-state Korean DEMO reactor. • Present a preliminary design of TF (toroidal field) magnet. • Present a preliminary design of CS (central solenoid) magnet. • Present a preliminary design of PF (toroidal field) magnet. - Abstract: As the ITER is being constructed, there is a growing anticipation for an earlier realization of fusion energy. A major design philosophy for the initiated conceptual design study for a steady-state Korean fusion demonstration reactor (K-DEMO) is engineering feasibility. A two-staged development plan is envisaged. K-DEMO is designed not only to demonstrate a net electricity generation and a self-sustained tritium cycle, but also to be used, in its initial stage, as a component test facility. Then, in its second stage, a major upgrade is carried out by replacing in-vessel components in order to show a net electricity generation on the order of 500 MWe. After a thorough 0-D system analysis, the major radius and minor radius are chosen to be 6.8 m and 2.1 m, respectively. In order to minimize wave deflection, a top-launch high frequency (>200 GHz) electron cyclotron current drive (ECCD) system will be the key system for the current profile control. For matching the high frequency ECCD, a high toroidal field (TF) is required and can be achieved by using high current density Nb{sub 3}Sn superconducting conductor. The peak magnetic field reaches to 16 T with the magnetic field at the plasma center above 7 T. Key features of the K-DEMO magnet system include the use of two TF coil winding packs, each of a different conductor design, to reduce the construction cost and save the space for the magnet structure material.

  14. Conceptual design study of the K-DEMO magnet system

    International Nuclear Information System (INIS)

    Kim, Keeman; Oh, Sangjun; Park, Jong Sung; Lee, Chulhee; Im, Kihak; Kim, Hyung Chan; Lee, Gyung-Su; Neilson, George; Brown, Thomas; Kessel, Charles; Titus, Peter; Zhai, Yuhu

    2015-01-01

    Highlights: • Perform a preliminary conceptual study for a steady-state Korean DEMO reactor. • Present a preliminary design of TF (toroidal field) magnet. • Present a preliminary design of CS (central solenoid) magnet. • Present a preliminary design of PF (toroidal field) magnet. - Abstract: As the ITER is being constructed, there is a growing anticipation for an earlier realization of fusion energy. A major design philosophy for the initiated conceptual design study for a steady-state Korean fusion demonstration reactor (K-DEMO) is engineering feasibility. A two-staged development plan is envisaged. K-DEMO is designed not only to demonstrate a net electricity generation and a self-sustained tritium cycle, but also to be used, in its initial stage, as a component test facility. Then, in its second stage, a major upgrade is carried out by replacing in-vessel components in order to show a net electricity generation on the order of 500 MWe. After a thorough 0-D system analysis, the major radius and minor radius are chosen to be 6.8 m and 2.1 m, respectively. In order to minimize wave deflection, a top-launch high frequency (>200 GHz) electron cyclotron current drive (ECCD) system will be the key system for the current profile control. For matching the high frequency ECCD, a high toroidal field (TF) is required and can be achieved by using high current density Nb_3Sn superconducting conductor. The peak magnetic field reaches to 16 T with the magnetic field at the plasma center above 7 T. Key features of the K-DEMO magnet system include the use of two TF coil winding packs, each of a different conductor design, to reduce the construction cost and save the space for the magnet structure material.

  15. Superconducting wind turbine generators

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Mijatovic, Nenad; Seiler, Eugen

    2010-01-01

    , the main challenge of the superconducting direct drive technology is to prove that the reliability is superior to the alternative drive trains based on gearboxes or permanent magnets. A strategy of successive testing of superconducting direct drive trains in real wind turbines of 10 kW, 100 kW, 1 MW and 10......We have examined the potential of 10 MW superconducting direct drive generators to enter the European offshore wind power market and estimated that the production of about 1200 superconducting turbines until 2030 would correspond to 10% of the EU offshore market. The expected properties of future...... offshore turbines of 8 and 10 MW have been determined from an up-scaling of an existing 5 MW turbine and the necessary properties of the superconducting drive train are discussed. We have found that the absence of the gear box is the main benefit and the reduced weight and size is secondary. However...

  16. Superconducting wind turbine generators

    International Nuclear Information System (INIS)

    Abrahamsen, A B; Seiler, E; Zirngibl, T; Andersen, N H; Mijatovic, N; Traeholt, C; Pedersen, N F; Oestergaard, J; Noergaard, P B

    2010-01-01

    We have examined the potential of 10 MW superconducting direct drive generators to enter the European offshore wind power market and estimated that the production of about 1200 superconducting turbines until 2030 would correspond to 10% of the EU offshore market. The expected properties of future offshore turbines of 8 and 10 MW have been determined from an up-scaling of an existing 5 MW turbine and the necessary properties of the superconducting drive train are discussed. We have found that the absence of the gear box is the main benefit and the reduced weight and size is secondary. However, the main challenge of the superconducting direct drive technology is to prove that the reliability is superior to the alternative drive trains based on gearboxes or permanent magnets. A strategy of successive testing of superconducting direct drive trains in real wind turbines of 10 kW, 100 kW, 1 MW and 10 MW is suggested to secure the accumulation of reliability experience. Finally, the quantities of high temperature superconducting tape needed for a 10 kW and an extreme high field 10 MW generator are found to be 7.5 km and 1500 km, respectively. A more realistic estimate is 200-300 km of tape per 10 MW generator and it is concluded that the present production capacity of coated conductors must be increased by a factor of 36 by 2020, resulting in a ten times lower price of the tape in order to reach a realistic price level for the superconducting drive train.

  17. Superconducting and Normal State Properties of OsB2*

    Science.gov (United States)

    Singh, Yogesh; Niazi, A.; Zong, X.; Suh, B. J.; Vannette, M. W.; Prozorov, R.; Johnston, D. C.

    2007-03-01

    OsB2 is a layered superhard metallic material that was found to superconduct below Tc= 2.1 K.^1 We report the first detailed measurements of the static and dynamic magnetic susceptibilities χ, electrical resistivity, heat capacity Cp, penetration depth, and ^11B NMR on OsB2 to characterize its superconducting and normal state properties. The results confirm that OsB2 is a bulk superconductor below Tc= 2.1 K@. Its properties can be described by a close to weak-coupling s-wave BCS model with an electron-phonon coupling constant λ= 0.4--0.5, δ(0)/(kBTc) 1.9, a small Ginzburg-Landau parameter κ of order 5 or less, and a small zero-temperature critical magnetic field of roughly 500 Oe. The ^11B NMR measurements in the normal state show a nuclear spin-lattice relaxation time T1= 2.1 s at room temperature and a Korringa law with T1T = 610 s.K at lower T, and a correspondingly small T-independent Knight shift. These results indicate a small s character of the conduction electron wave function at the B site at the Fermi level. Our results will be compared to corresponding data for MgB2.1. J. K. Vandenberg et al., Mater. Res. Bull. 10, 889 (1975).^*Supported by the USDOE under Contract No. W-7405-Eng-82. Permanent address: Dept. Phys., The Catholic Univ. Korea.

  18. Studi Keamanan dan Keandalan Suplai Sistem Kelistrikan Bali Sesuai Rencana Operasi SUTET 500 kV

    Directory of Open Access Journals (Sweden)

    Bawa Adiputra

    2014-12-01

    Full Text Available Kondisi eksisting kelistrikan Bali hingga tahun 2013 disuplai oleh tiga pembangkit tenaga listrik dan sebuah sistem interkoneksi Jamali dengan keseluruhan daya suplai sebesar 676 MW. Berdasarkan peramalan beban sistem Bali 2013-2030 diperoleh rata-rata pertumbuhan beban 6,61%. Berdasarkan hal tersebut PT PLN (Persero merencanakan penambahan pasokan daya listrik ke pulau Bali dengan penambahan kabel laut, suplai melalui SUTET 500 kV interkoneksi Jawa-Bali, serta pembangunan PLTU Celukan Bawang 980 MW. Dengan beroperasinya unit-unit tersebut diperlukan analisis keamanan suplai sistem kelistrikan Bali, dengan dua skenario. Skenario 1 yaitu sistem Bali hanya menerima pasokan dari PLTU Celukan Bawang pada tahun 2016 sebesar 380 MW. Skenario 2, PLTU Celukan Bawang beroperasi sebesar 380 MW tahun 2016, kemudian pada tahun 2020 dan 2022 menambah daya masing-masing 300 MW. Selain analisis keamanan suplai dilakukan juga analisis keandalan dengan beroperasinya SUTET 500 kV di Bali. Analisis keandalan SUTET 500 kV menggunakan tiga skenario. Skenario 1 SUTET beroperasi dari Paiton sampai di GITET Gilimanuk, Skenario 2 SUTET beroperasi dari PAITON sampai di GITET New Kapal, dan Skenario 3 SUTET beroperasi dari Paiton sampai di GITET Kapal. Dari hasil analisis keamanan suplai diperoleh skenario 1, pada tahun 2022 beban puncak mencapai 1304,10 MW dan pada kondisi N-1 mengalami krisis daya listrik -48,3 MW. Skenario 2, pada tahun 2028 dengan beban puncak 1862,60 MW dan pada kondisi N-1 mengalami krisis daya listrik -6,8 MW. Sedangkan analisis keandalan beroperasinya SUTET 500 kV di Bali diperoleh: Skenario 1 nilai SAIFI = 2,0 kali/km/tahun dan nilai SAIDI = ±10 menit/tahun, Skenario 2 nilai SAIFI = 3,1 kali/km/tahun dan nilai SAIDI = ±15 menit/tahun, Skenario 3 nilai SAIFI = 3,3 kali/km/tahun dan nilai SAIDI = ±17 menit/tahun.

  19. Experimentally stabilized superconducting magnet with inner diameter of 700 mm

    Energy Technology Data Exchange (ETDEWEB)

    Vetlitskii, I A; Belonogov, A V; Dobrov, V M; Krylov, V L; Lebedev, A V; Lomkatsi, G S; Nilov, A F; Smolyankin, V T

    1974-05-01

    An experimental magnet, SPM-70, with the following characteristics was constructed. The inner diameter of the winding was 730 mm; outer diameter of the winding 1000 mm; height of winding 310 mm; magnetic induction at the center of the magnet 1.45 T; maximum magnetic induction 2.4 T; operation current 820 A; ampere-turns 1.07 x 10/sup 6/; design current density 2560 A/cm/sup 2/; stored energy 500 kJ; superconducting alloy Nb+50% Zr; weight of superconductor 23 kg; weight of copper 210 kg; resistivity of the copper in the strips at T = 4.2 K, B = 2.5 T, 2.6 x 10/sup -8/ ..cap omega.. cm.

  20. Hybrid superconducting a.c. current limiter extrapolation 63 kV-1 250 A

    Science.gov (United States)

    Tixador, P.; Levêque, J.; Brunet, Y.; Pham, V. D.

    1994-04-01

    Following the developement of a.c. superconducting wires a.c. current superconducting limiters have emerged. These limiters limit the fault currents nearly instantaneously, without detection nor order giver and may be suitable for high voltages. They are based on the natural transition from the superconducting state to the normal resistive state by overstepping the critical current of a superconducting coil which limits or triggers the limitation. Our limiter device consists essentially of two copper windings coupled through a saturable magnetic circuit and of a non inductively wound superconducting coil with a reduced current compared to the line current. This design allows a simple superconducting cable and reduced cryogenic losses but the dielectric stresses are high during faults. A small model (150 V/50 A) has experimentally validated our design. An industrial scale current limiter is designed and the comparisons between this design and other superconducting current limiters are given. Les courants de court-circuit sur les grands réseaux électriques ne cessent d'augmenter. Dans ce contexte sont apparus les limiteurs supraconducteurs de courant suite au développement des brins supraconducteurs alternatifs. Ces limiteurs peuvent limiter les courants de défaut presque instantanément, sans détection de défaut ni donneur d'ordre et ils sont extrapolables aux hautes tensions. Ils sont fondés sur la transition naturelle de l'état supraconducteur à l'état normal très résistif par dépassement du courant critique d'un enroulement supraconducteur qui limite ou déclenche la limitation. Notre limiteur est composé de deux enroulements en cuivre couplés par un circuit magnétique saturable et d'une bobine supraconductrice à courant réduit par rapport au courant de la ligne. Cette conception permet un câble supraconducteur simple et des pertes cryogéniques réduites mais les contraintes diélectriques en régime de défaut sont importantes. Une maquette

  1. Biomedical research with cyclotron produced radionuclides. Progress report, October 1, 1977--September 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Laughlin, J.S.; Benua, R.S.; Tilbury, R.S.; Bigler, R.E.

    1978-09-30

    Progress is reported on biomedical studies using cyclotron-produced /sup 18/F, /sup 15/O, /sup 11/C, /sup 13/N, /sup 52/Fe, /sup 38/K, /sup 206/Bi, /sup 73/Se, /sup 53/Co, and /sup 43/K. The following research projects are described: tumor detection and diagnosis; neurological studies; radiopharmaceutical development; /sup 38/K as an indicator of blood flow to the myocardium; dosimetry for internally deposited isotopes in animals and man; cyclotron development; positron tomographic imaging with the TOKIM System; and review of positron emission transaxial tomograph instruments. (HLW)

  2. Design of a large superconducting spectrometer magnet

    International Nuclear Information System (INIS)

    Shintomi, T.; Makida, Y.; Mito, T.; Yamanoi, Y.; Hashimito, O.; Nagae, T.

    1989-04-01

    The superconducting spectrometer magnet for nuclear physics experiments has been under construction by Institute for Nuclear Study, University of Tokyo with collaboration from KEK. The magnet has a sector type coil. The magnetic field is 3 T with the magnet gap of 50 cm and the stored energy is 11.8 MJ. The easy operation and maintenance are taken into consideration in addition to usual design concept. Three dimensional magnetic field calculation and the stress analysis have been performed. The code 'QUENCH' was applied to decide the operation current and to check the safety of the coil. As a result, the current of 500 A was selected. The heat leaks were checked and estimated less than 2 W at 4 K. A small refrigerator is to be used for thermal insulations at 80 and 20 K. (author)

  3. Development of a Solid State RF Amplifier in the kW Regime for Application with Low Beta Superconducting RF Cavities

    CERN Document Server

    Piel, Christian; Borisov, A; Kolesov, Sergej; Piel, Helmut

    2005-01-01

    Projects based on the use of low beta superconducting cavities for ions are under operation or development at several labs worldwide. Often these cavities are individually driven by RF power sources in the kW regime. For an ongoing project a modular 2 kW, 176 MHz unconditionally stable RF amplifier for CW and pulsed operation was designed, built, and tested. Extended thermal analysis was used to develop a water cooling system in order to optimize the performance of the power transistors and other thermally loaded components. The paper will outline the design concept of the amplifier and present first results on the test of the amplifier with a superconducting cavity.

  4. Superconducting magnets and cryogenics for the steady state superconducting tokamak SST-1

    International Nuclear Information System (INIS)

    Saxena, Y.C.

    2000-01-01

    SST-1 is a steady state superconducting tokamak for studying the physics of the plasma processes in tokamak under steady state conditions and to learn technologies related to the steady state operation of the tokamak. SST-1 will have superconducting magnets made from NbTi based conductors operating at 4.5 K temperature. The design of the superconducting magnets and the cryogenic system of SST-1 tokamak are described. (author)

  5. MICHIGAN: Cyclotron conference

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-10-15

    A sense of excitement was in the air as cyclotron physicists and engineers from 17 countries convened on 30 April for the opening of the Tenth International Conference on Cyclotrons and Their Applications. Some 50 years after its invention, the redoubtable cyclotron remains a topic of compelling current interest. Cyclotron experts gathered at Michigan State University's Kellogg Center to hear of latest developments, of progress and successes on new machines which had come into operation, of new projects which were underway, and of dreams which lay ahead.

  6. Neutron radiography by using JSW baby cyclotron

    International Nuclear Information System (INIS)

    Toda, Yojiro

    1995-01-01

    At present, JSW baby cyclotrons are mostly used for the production of the radioisotopes for medical use. The attempt to use this baby cyclotron for neutron radiography began already in 1981. The feasibility of the neutron radiography for the explosives in metallic cases which are used for H1 rockets was investigated. In 1983, it was shown that the neutron radiography by using the baby cyclotron in Muroran Works, Japan Steel Works, Ltd. was able to be carried out as a routine work. Since then, the nondestructive inspection by neutron radiography has been performed for rocket pyrotechnic articles, and contributed to heighten their reliability. Further, the radiography by using fast neutrons was developed and put to practical use for recent large H2 rockets. The JSW baby cyclotron BC 168 which has been used for neutron radiography can accelerate 16 MeV protons or 8 MeV deuterons up to 50 μA. The principle of thermal neutron radiography is the generation of fast neutrons by irradiating a Be target with the proton beam accelerated by a baby cyclotron, the moderation of the fast neutrons, the formation of the thermal neutron flux of uniform distribution with a collimator, the thermal neutron flux hitting the Gd plate in a film cassette through an object, and the exposure of an X-ray film to electrons from the Gd plate. Fast neutron radiography apparatus, and commercial neutron radiography are described. (K.I.)

  7. Preparation dependent superconductivity in T1CaBa2Cu3O7.5+-d above 100 K

    International Nuclear Information System (INIS)

    Porjesz, T.; Halasz, I.; Traeger, T.; Kovacs, G.; Kirschner, I.; Zsolt, G.; Karman, T.

    1988-08-01

    Different heat treatment procedures were applied during the sample preparation process, which result in different superconducting properties in the samples of the same nominal composition of TlCaBa 2 Cu 3 O 7.5+-d . It manifests itself in the different critical temperatures having values of 104 K, 107 K and 93 K. The effect of heat treatments is reflected in the structural and magnetic properties as well. (author). 6 refs, 5 figs

  8. The polarized proton and deuteron beam at the Bonn isochronous cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, K G; Enders, R; Hammon, W; Krause, K D; Lesemann, D; Scholzen, A [Bonn Univ. (F.R. Germany). Inst. fuer Angewandte Physik; Euler, K; Schueller, B [Bonn Univ. (F.R. Germany). Inst. fuer Strahlen- und Kernphysik

    1976-02-15

    The present state of the polarized proton and deuteron source at the Bonn cyclotron is described. The source, which is of the atomic beam type, gives typical ion beam intensities of 2 ..mu..A for protons and 3 ..mu..A for deuterons. The overall transmission from the source to the first stopper after extraction from the cyclotron is 3%. Target currents with an energy resolution E/..delta..E=500 are 20 nA for deuterons and 10 nA for protons. For the proton beam, a polarization P=-0.71 was measured. For the deuteron beam, a pure vector polarization Psub(z)=-0.47 or various mixtures of vector and tensor polarization are obtained.

  9. Recent advances in fullerene superconductivity

    CERN Document Server

    Margadonna, S

    2002-01-01

    Superconducting transition temperatures in bulk chemically intercalated fulleride salts reach 33 K at ambient pressure and in hole-doped C sub 6 sub 0 derivatives in field-effect-transistor (FET) configurations, they reach 117 K. These advances pose important challenges for our understanding of high-temperature superconductivity in these highly correlated organic metals. Here we review the structures and properties of intercalated fullerides, paying particular attention to the correlation between superconductivity and interfullerene separation, orientational order/disorder, valence state, orbital degeneracy, low-symmetry distortions, and metal-C sub 6 sub 0 interactions. The metal-insulator transition at large interfullerene separations is discussed in detail. An overview is also given of the exploding field of gate-induced superconductivity of fullerenes in FET electronic devices.

  10. Electromagnetic cyclotron harmonic waves

    International Nuclear Information System (INIS)

    Ohnuma, T.; Watanabe, T.; Hamamatsu, K.

    1981-09-01

    Electromagnetic electron cyclotron harmonic waves just below the electron cyclotron harmonics are investigated numerically and experimentally. Backward waves which are observed to propagate nearly perpendicular to the magnetic field just below the electron cyclotron frequency in a high density magnetoplasma are confirmed to be in accord with the theoretical electromagnetic cyclotron waves. (author)

  11. Design and development of a high-power, 500 kV pulsed line

    International Nuclear Information System (INIS)

    Nicolas, A.

    A study was made of very high voltage (500 kV) pulse production for 50 ns at half height. A coaxial line was coupled to a Marx generator for obtaining the pulses on an impedance-adapted electron diode. The maximum power obtained was 6.4 x 10 10 W with a current front in the diode of about 30 ns (80 ns pulse length at half height)

  12. MICHIGAN: Cyclotron conference

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    A sense of excitement was in the air as cyclotron physicists and engineers from 17 countries convened on 30 April for the opening of the Tenth International Conference on Cyclotrons and Their Applications. Some 50 years after its invention, the redoubtable cyclotron remains a topic of compelling current interest. Cyclotron experts gathered at Michigan State University's Kellogg Center to hear of latest developments, of progress and successes on new machines which had come into operation, of new projects which were underway, and of dreams which lay ahead

  13. Superconducting fault current limiter for railway transport

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, L. M., E-mail: LMFisher@niitfa.ru; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V. [National Technical Physics and Automation Research Institute (Russian Federation)

    2015-12-15

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered.

  14. Superconducting fault current limiter for railway transport

    International Nuclear Information System (INIS)

    Fisher, L. M.; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V.

    2015-01-01

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered

  15. Superconducting nanowire single photon detectors fabricated from an amorphous Mo{sub 0.75}Ge{sub 0.25} thin film

    Energy Technology Data Exchange (ETDEWEB)

    Verma, V. B.; Lita, A. E.; Vissers, M. R.; Marsili, F.; Pappas, D. P.; Mirin, R. P.; Nam, S. W. [National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305 (United States)

    2014-07-14

    We present the characteristics of superconducting nanowire single photon detectors (SNSPDs) fabricated from amorphous Mo{sub 0.75}Ge{sub 0.25} thin-films. Fabricated devices show a saturation of the internal detection efficiency at temperatures below 1 K, with system dark count rates below 500 cps. Operation in a closed-cycle cryocooler at 2.5 K is possible with system detection efficiencies exceeding 20% for SNSPDs which have not been optimized for high detection efficiency. Jitter is observed to vary between 69 ps at 250 mK and 187 ps at 2.5 K using room temperature amplifiers.

  16. Control of the superconducting magnet power supply for SECRAL

    International Nuclear Information System (INIS)

    Zhou Wenxiong; Wang Yanyu; Zhou Detai; Lu Wang; Feng Yucheng; Su Jianjun

    2014-01-01

    The control of the superconducting magnet power supply (SMPS) is very important for Superconducting Electron Cyclotron Resonance Ion source with Advanced design in Lanzhou (SECRAL). In order to improve the safety and the reliability of the SMPS, a remote control system was designed and implemented. There are four power supplies needed to be controlled with suitable strategy to avoid the quench of the superconducting magnet. These four power supplies are used to supply four superconducting solenoids. Because the value and the changing rates of the current for these four solenoids are different, the power supplies must be operated synchronously to keep the current of the solenoids balanced. In this paper, we provide a detailed description for the control strategy of the four power supplies and the architecture of the hardware and the software. A serial switch is used for protocol conversion between TCP/IP and RS232 in firmware. And the software is implemented using VC++. The system can operate the four power supplies automatically after it is triggered. With the help of the control system, operation of the SMPS gets easier and safer. (authors)

  17. Commissioning of the superconducting ECR ion source VENUS

    International Nuclear Information System (INIS)

    Leitner, Daniela; Abbott, Steve R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde; Lyneis, Claude M.

    2003-01-01

    VENUS (Versatile ECR ion source for NUclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The magnetic confinement configuration consists of three superconducting axial coils and six superconducting radial coils in a sextupole configuration. The nominal design fields of the axial magnets are 4T at injection and 3T at extraction; the nominal radial design field strength at the plasma chamber wall is 2T, making VENUS the world most powerful ECR plasma confinement structure. The magnetic field strength has been designed for optimum operation at 28 GHz. The four-year VENUS project has recently achieved two major milestones: The first plasma was ignited in June, the first mass-analyzed high charge state ion beam was extracted in September of 2002. The pa per describes the ongoing commissioning. Initial results including first emittance measurements are presented

  18. Development of Infrastructure Facilities for Superconducting RF Cavity Fabrication, Processing and 2 K Characterization at RRCAT

    Science.gov (United States)

    Joshi, S. C.; Raghavendra, S.; Jain, V. K.; Puntambekar, A.; Khare, P.; Dwivedi, J.; Mundra, G.; Kush, P. K.; Shrivastava, P.; Lad, M.; Gupta, P. D.

    2017-02-01

    An extensive infrastructure facility is being established at Raja Ramanna Centre for Advanced Technology (RRCAT) for a proposed 1 GeV, high intensity superconducting proton linac for Indian Spallation Neutron Source. The proton linac will comprise of a large number of superconducting Radio Frequency (SCRF) cavities ranging from low beta spoke resonators to medium and high beta multi-cell elliptical cavities at different RF frequencies. Infrastructure facilities for SCRF cavity fabrication, processing and performance characterization at 2 K are setup to take-up manufacturing of large number of cavities required for future projects of Department of Atomic Energy (DAE). RRCAT is also participating in a DAE’s approved mega project on “Physics and Advanced technology for High intensity Proton Accelerators” under Indian Institutions-Fermilab Collaboration (IIFC). In the R&D phase of IIFC program, a number of high beta, fully dressed multi-cell elliptical SCRF cavities will be developed in collaboration with Fermilab. A dedicated facility for SCRF cavity fabrication, tuning and processing is set up. SCRF cavities developed will be characterized at 2K using a vertical test stand facility, which is already commissioned. A Horizontal Test Stand facility has also been designed and under development for testing a dressed multi-cell SCRF cavity at 2K. The paper presents the infrastructure facilities setup at RRCAT for SCRF cavity fabrication, processing and testing at 2K.

  19. Development of superconducting equipment for fusion device

    International Nuclear Information System (INIS)

    Konno, Masayuki; Ueda, Toshio; Hiue, Hisaaki; Ohgushi, Kouzou

    1993-01-01

    At Fuji Electric Co., Ltd., the development of superconductivity was started from 1960, and superconducting equipment for fusion device has been developed for ten years. The superconducting equipment, which is developed for fusion by Fuji Electric Co., Ltd., are able to be grouped in three categories which are current lead, superconducting coil and superconducting bus-line. The current lead is an electrical feeder between a superconducting coil and an electrical power supply. The rated current of developed current lead is 30kA at continuous use and 100kA at short time use respectively. The advanced disk type coil is developed for the toroidal field coil and some coils are developed for critical current measurement. Superconductor is applied to the superconducting bus-line between the superconducting coils and the current leads, and the bus-line is being developed for the Large Helical Device. This report describes an abstract of these equipment. (author)

  20. Superconducting machines. Chapter 4

    International Nuclear Information System (INIS)

    Appleton, A.D.

    1977-01-01

    A brief account is given of the principles of superconductivity and superconductors. The properties of Nb-Ti superconductors and the method of flux stabilization are described. The basic features of superconducting d.c. machines are illustrated by the use of these machines for ship propulsion, steel-mill drives, industrial drives, aluminium production, and other d.c. power supplies. Superconducting a.c. generators and their design parameters are discussed. (U.K.)

  1. Football coil: a device to produce absolute minimum magnetic field and an isochronous cyclotron for heavy ions

    International Nuclear Information System (INIS)

    Szu, H.H.

    1977-01-01

    An electric solenoid is considered which consists of several discrete, circular and superconducting wires. The size of each loop varies from one to several meters in the radius. Furthermore, if such a solenoid is made into a football shape by squeezing the ends symmetrically, it is referred to here as a football coil. A discussion is given of the theory of synergic focusing; phase stability and universal orbit; application and computer simulation; and ion self-fields and self-focusing. An isochronous cyclotron was designed using the superconducted football coil and van resonators with flare height. It can accelerate various species of heavy ions; the heavier the rest mass of an ion, the better the present scheme will be

  2. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  3. Superconducting Submm Integrated Receiver for TELIS

    Energy Technology Data Exchange (ETDEWEB)

    Koshelets, V P [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Ermakov, A B [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Filippenko, L V [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Koryukin, O V [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Khudchenko, A V [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Sobolev, A S [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Torgashin, M Yu [Institute of Radio Engineering and Electronics (IREE) (Russian Federation); Yagoubov, P A [SRON National Institute for Space Research (Netherlands); Hoogeveen, R W M [SRON National Institute for Space Research (Netherlands); Vreeling, W J [SRON National Institute for Space Research (Netherlands); Wild, W [SRON National Institute for Space Research (Netherlands); Pylypenko, O M [State Research Center of Superconducting Electronics ' Iceberg' (Ukraine)

    2006-06-01

    In this report we present design and first experimental results for development of the submm superconducting integrated receiver spectrometer for Terahertz Limb Sounder (TELIS). TELIS is a collaborative European project to build up a three-channel heterodyne balloon-based spectrometer for measuring a variety of atmospheric constituents of the stratosphere. The 550 - 650 GHz channel of TELIS is based on a phase-locked Superconducting Integrated Receiver (SIR). SIR is an on-chip combination of a low-noise Superconductor-Insulator-Superconductor (SIS) mixer with quasioptical antenna, a superconducting Flux Flow Oscillator (FFO) acting as Local Oscillator (LO), and SIS harmonic mixer (HM) for FFO phase locking. A number of new solutions were implemented in the new generation of SIR chips. To achieve the wide-band performance of the spectrometer, a side-feed twin-SIS mixer and balanced SIS mixer with 0.8 {mu}m{sup 2} junctions integrated with a double-dipole (or double-slot) antenna is used. An improved design of the FFO for TELIS has been developed and optimized providing a free-running linewidth between 10 and 2 MHz in the frequency range 500 - 700 GHz. It is important to ensure that tuning of a phase-locked (PL) SIR can be performed remotely by telecommand. For this purpose a number of approaches for the PL SIR automatic computer control have been developed. All receiver components (including input optical elements and Martin-Puplett polarization rotating interferometer for single side band operation) will be mounted on a single 4.2 K plate inside a 40 x 180 x 80 mm{sup 3} box. First measurements give an uncorrected double side band (DSB) noise temperature below 250 K measured with the phase-locked FFO; more detailed results are presented at the conference.

  4. Superconducting Submm Integrated Receiver for TELIS

    International Nuclear Information System (INIS)

    Koshelets, V P; Ermakov, A B; Filippenko, L V; Koryukin, O V; Khudchenko, A V; Sobolev, A S; Torgashin, M Yu; Yagoubov, P A; Hoogeveen, R W M; Vreeling, W J; Wild, W; Pylypenko, O M

    2006-01-01

    In this report we present design and first experimental results for development of the submm superconducting integrated receiver spectrometer for Terahertz Limb Sounder (TELIS). TELIS is a collaborative European project to build up a three-channel heterodyne balloon-based spectrometer for measuring a variety of atmospheric constituents of the stratosphere. The 550 - 650 GHz channel of TELIS is based on a phase-locked Superconducting Integrated Receiver (SIR). SIR is an on-chip combination of a low-noise Superconductor-Insulator-Superconductor (SIS) mixer with quasioptical antenna, a superconducting Flux Flow Oscillator (FFO) acting as Local Oscillator (LO), and SIS harmonic mixer (HM) for FFO phase locking. A number of new solutions were implemented in the new generation of SIR chips. To achieve the wide-band performance of the spectrometer, a side-feed twin-SIS mixer and balanced SIS mixer with 0.8 μm 2 junctions integrated with a double-dipole (or double-slot) antenna is used. An improved design of the FFO for TELIS has been developed and optimized providing a free-running linewidth between 10 and 2 MHz in the frequency range 500 - 700 GHz. It is important to ensure that tuning of a phase-locked (PL) SIR can be performed remotely by telecommand. For this purpose a number of approaches for the PL SIR automatic computer control have been developed. All receiver components (including input optical elements and Martin-Puplett polarization rotating interferometer for single side band operation) will be mounted on a single 4.2 K plate inside a 40 x 180 x 80 mm 3 box. First measurements give an uncorrected double side band (DSB) noise temperature below 250 K measured with the phase-locked FFO; more detailed results are presented at the conference

  5. 1D-transport properties of single superconducting lead nanowires

    DEFF Research Database (Denmark)

    Michotte, S.; Mátéfi-Tempfli, Stefan; Piraux, L.

    2003-01-01

    of the nanowire is small enough to ensure a 1D superconducting regime in a wide temperature range below T. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied DC current......We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have uniform diameter of ̃40 nm and a very large aspect ratio (̃500). The diameter...

  6. The importance of plasma effects on electron-cyclotron maser-emission from flaring loops

    Science.gov (United States)

    Sharma, R. R.; Vlahos, L.; Papadopoulos, K.

    1982-01-01

    Electron cyclotron maser instability has been suggested as the cause of the observed short (10-20 msec), intense (an approximate brightness temperature of 10 to the 15th K) and up to 100% polarized microwave solar emission. It is shown that plasma effects and thermal cyclotron damping, ignored in previous theories, play an important role in controlling the frequency range of the emission. The radio emission is suppressed for ratios of the plasma frequency to the cyclotron frequency smaller than 0.4. An examination of the cyclotron damping, reveals that the maser action is suppressed unless a large fraction (i.e., over 10%) of the accelerated electrons participates in the emission process.

  7. Quench Propagation in the Superconducting 6 kA Flexible Busbars of the LHC

    OpenAIRE

    Calvi, M; Herzog, R; Pelegrin-Carcelen, J M; Sonnemann, F

    2001-01-01

    Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recom...

  8. Recommendation for a injector-cyclotron and ion sources for the acceleration of heavy ions and polarized protons and deuterons

    International Nuclear Information System (INIS)

    Botha, A.H.; Cronje, P.M.; Du Toit, Z.B.; Nel, W.A.G.; Celliers, P.J.

    1984-01-01

    It was decided to accelerate both heavy and light ions with the open-sector cyclotron. The injector SPS1, was used for light ions and SPS2 for heavy ions. Provision was also made for the acceleration of polarized neutrons. To enable this, the injector must have an axial injection system. The working of a source of polarized ions and inflectors for an axial injection system is discussed. The limitations of the open-sector cyclotron on the acceleration of heavy ions are also dealt with. The following acceleration/ion source combinations are discussed: i) The open-sector cyclotron and a k=40 injector cyclotron with a Penning ion source, and a stripper between the injector and the open-sector cyclotron and also a source of polarized protons and deuterons; ii) The acceleration/ion source combination with the addition of electron beam ion sources; iii) The open-sector cyclotron and a k=11 injector cyclotron with a electron beam ion source and a source of polarized protons and deuterons

  9. Electronic structure and superconductivity of FeSe-related superconductors.

    Science.gov (United States)

    Liu, Xu; Zhao, Lin; He, Shaolong; He, Junfeng; Liu, Defa; Mou, Daixiang; Shen, Bing; Hu, Yong; Huang, Jianwei; Zhou, X J

    2015-05-13

    FeSe superconductors and their related systems have attracted much attention in the study of iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a superconducting transition temperature (Tc) of ~8 K and it can be dramatically enhanced to 37 K at high pressure. On the other hand, its cousin system, FeTe, possesses a unique antiferromagnetic ground state but is non-superconducting. Substitution of Se with Te in the FeSe superconductor results in an enhancement of Tc up to 14.5 K and superconductivity can persist over a large composition range in the Fe(Se,Te) system. Intercalation of the FeSe superconductor leads to the discovery of the AxFe2-ySe2 (A = K, Cs and Tl) system that exhibits a Tc higher than 30 K and a unique electronic structure of the superconducting phase. A recent report of possible high temperature superconductivity in single-layer FeSe/SrTiO3 films with a Tc above 65 K has generated much excitement in the community. This pioneering work opens a door for interface superconductivity to explore for high Tc superconductors. The distinct electronic structure and superconducting gap, layer-dependent behavior and insulator-superconductor transition of the FeSe/SrTiO3 films provide critical information in understanding the superconductivity mechanism of iron-based superconductors. In this paper, we present a brief review of the investigation of the electronic structure and superconductivity of the FeSe superconductor and related systems, with a particular focus on the FeSe films.

  10. Cyclotron waves in plasma

    International Nuclear Information System (INIS)

    Lominadse, D.G.

    1975-01-01

    The book deals with fundamental physical concepts of the theory of cyclotron waves and cyclotron instabilities conditioned by the presence in plasma of direct or alternating electric currents passing in it perpendicularily to a magnetic field. A great variety of problems is considered connected with the linear theory of cyclotron oscillations in equilibrium and electron plasma of metals and semiconductors. Parametric excitations of electron cyclotron oscillations of plasma in an alternating electric field are studied. Particular attention is paid to the investigation of plasma turbulence arising as a result of development of cyclotron instabilities. Experimental data are discussed and compared with theoretical results

  11. Cyclotrons: 1978

    International Nuclear Information System (INIS)

    Martin, J.A.

    1978-01-01

    A compilation is presented of the experimental facilities of the world's cyclotrons including history and status, staff and operation, research staff, target facilities, magnet, acceleration system, vacuum system, characteristic beams, beam properties, and a plan view of the facility for each cyclotron

  12. Damage by the Great East Japan Earthquake and current status of the Sendai cyclotron

    International Nuclear Information System (INIS)

    Wakui, Takashi; Itoh, Masatoshi; Shimada, Kenzi; Yoshida, Hidetomo; Shinozuka, Tsutomu; Sakemi, Yasuhiro

    2012-01-01

    The Great East Japan Earthquake has inflicted damages on the accelerator facility of the Cyclotron and Radioisotope Center (CYRIC), Tohoku University. The K=110 MeV cyclotron was slanted due to the damage of props supporting the cyclotron. The cyclotron building has also been slightly inclined. This situation requires the re-alignment of all the beam transport line and the cyclotron. Some of the shield doors at experimental rooms were broken and blocked the entrance. The earthquake caused also a lot of damages to some components of the cyclotron as well as the beam transport lines, such as beam ducts, magnets, vacuum pumps and power supplies. Fortunately, no one was injured at CYRIC. The restoration work was started on July 2011 and will be completed by July 2012. This report describes the situation of damages and the current status of the restoration work. (author)

  13. Band rejection filter for measurement of electron cyclotron emission during electron cyclotron heating

    International Nuclear Information System (INIS)

    Iwase, Makoto; Ohkubo, Kunizo; Kubo, Shin; Idei, Hiroshi.

    1996-05-01

    For the measurement of electron cyclotron emission from the high temperature plasma, a band rejection filter in the range of 40-60 GHz is designed to reject the 53.2 GHz signal with large amplitude from the gyrotron for the purpose of plasma electron heating. The filter developed with ten sets of three quarters-wavelength coupled by TE 111 mode of tunable resonant cavity has rejection of 50 dB and 3 dB bandwidth of 500 MHz. The modified model of Tschebysheff type for the prediction of rejection is proposed. It is confirmed that the measured rejection as a function of frequency agrees well with the experimental results for small coupling hole, and also clarified that the rejection ratio increases for the large coupling hole. (author)

  14. Commissioning of the superconducting ECR ion source VENUS at 18 GHz

    International Nuclear Information System (INIS)

    Leitner, Daniela; Abbott, Steven R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde E.; Lyneis, Claude M.

    2004-01-01

    During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation are now underway. During the commissioning phase with 18 GHz, tests with various gases and metals have been performed with up to 2000 W RF power. The ion source performance is very promising [1,2]. VENUS (Versatile ECR ion source for Nuclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The goal of the VENUS ECR ion source project as the RIA R and D injector is the production of 240e(micro)A of U 30+ , a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5e(micro)A of U 48+ , a low current, very high charge state beam. To meet these ambitious goals, VENUS has been designed for optimum operation at 28 GHz. This frequency choice has several design consequences. To achieve the required magnetic confinement, superconducting magnets have to be used. The size of the superconducting magnet structure implies a relatively large plasma volume. Consequently, high power microwave coupling becomes necessary to achieve sufficient plasma heating power densities. The 28 GHz power supply has been delivered in April 2004

  15. Preliminary study on AC superconducting machines

    International Nuclear Information System (INIS)

    Yamamoto, M.; Ishigohka, T.; Shimohka, T.; Mizukami, N.; Yamaguchi, M.

    1988-01-01

    This paper describes the issues involved in developing AC superconducting machines. In the first phase, as a preliminary experiment, a 4kVa AC superconducting coil which employs 100A class 50/60Hz superconductors is made and tested. And, in the second phase, as an extension of the 4kVa coil, a model superconducting transformer is made and examined. The transformer has a novel quench protection system with an auxiliary coil only in the low voltage side. The behavior of the overcurrent protection system is confirmed

  16. Surface ferromagnetism and superconducting properties of nanocrystalline niobium nitride

    International Nuclear Information System (INIS)

    Shipra, R.; Kumar, Nitesh; Sundaresan, A.

    2013-01-01

    Nanocrystalline δ-NbN x samples have been synthesized by reacting NbCl 5 and urea at three different temperatures. A comparison of their structural, magnetic, transport and thermal properties is reported in the present study. The size of the particles and their agglomeration extent increase with increasing reaction temperature. The sample prepared at 900 °C showed the highest superconducting transition temperature (T c ) of 16.2 K with a transition width, ∼1.8 K, as obtained from the resistivity measurement on cold-pressed bars. Above T c , magnetization measurements revealed the presence of surface ferromagnetism which coexists with superconductivity below T c . Heat capacity measurements confirm superconductivity with strong electron–phonon coupling constant. The sample prepared at 800 °C shows a lower T c (10 K) while that prepared at 700 °C exhibit no superconductivity down to the lowest temperature (3 K) measured. - Highlights: ► Synthesis of δ-NbN nanoparticles by urea nitridation of NbCl 5 . ► Superconducting transition temperature (T c ) is 16.2 K. ► Superconductivity and surface ferromagnetism coexist in the nanoparticles. ► Effect of size and agglomeration on the physical properties of nanoparticles

  17. Superconducting current generators

    International Nuclear Information System (INIS)

    Genevey, P.

    1970-01-01

    After a brief summary of the principle of energy storage and liberation with superconducting coils,two current generators are described that create currents in the range 600 to 1400 A, used for two storage experiments of 25 kJ and 50 kJ respectively. The two current generators are: a) a flux pump and b) a superconducting transformer. Both could be developed into more powerful units. The study shows the advantage of the transformer over the flux pump in order to create large currents. The efficiencies of the two generators are 95 per cent and 40 to 60 per cent respectively. (author) [fr

  18. Ion-cyclotron-resonance heating in the Wisconsin Levitated Octupole

    International Nuclear Information System (INIS)

    Fortgang, C.M.; Sprott, J.C.; Strait, E.J.

    1983-06-01

    Ion-cyclotron-resonance heating has been investigated, both experimentally and theoretically, on the Wisconsin Levitated Octupole. Heating of both ions and electrons has been observed. Typically, a two-component ion energy distribution is produced (300 eV and 50 eV) with 500 kW of rf power coupled into a 5 x 10 12 cm -3 plasma. Power is coupled to the plasma with an antenna that also serves as the inductor of an oscillator tank circuit. The oscillator is tunable from 1 to 3 MHz and can be applied for periods up to 10 msec. The experiments were performed with hydrogen, gun-injected plasmas. Most of the theortical work presented deals with a calculation that predicts the plasma loading. A slab model is used, and the questions of accessibility, polarization, and damping of the radio-frequency electromagnetic fields are addressed. It is found that cold-plasma theory cannot account for the heating and, therefore, hot-plasma theory is invoked to explain the results. The loading measurements and theoretical predictions are found to be in reasonable agreement

  19. Fullerides - Superconductivity at the limit

    NARCIS (Netherlands)

    Palstra, Thomas T. M.

    The successful synthesis of highly crystalline Cs3C60, exhibiting superconductivity up to a record temperature for fullerides of 38 K, demonstrates a powerful synthetic route for investigating the origin of superconductivity in this class of materials.

  20. Radioisotope production by reactors and cyclotrons in Japan

    International Nuclear Information System (INIS)

    Murakami, Yukio

    1978-01-01

    Present status of radioisotope production in Japan and the increasing demand from various fields are generally reviewed. Future problems associated with the shortage of economical supply are also discussed. The first half of this report is devoted to general review of the increasing demand for various radioisotopes from increasing number of users. The present status and future trends of the distribution of users of specific radioisotopes and their demands are shown. The remaining half of this report reviews the production with reactors and cyclotrons. The Japanese reactors producing radioisotopes are limited to low flux (10 13 ) research reactors at JAERI. Some problems associated with the improvement of availability and with the organizational structure are discussed. As for the production with cyclotrons, available facilities and the method of production are explained in detail. For clinical use, especially for the production of short lived radioisotopes, the advantage of a small special purpose cyclotron at each medical organization is emphasized. (Aoki, K.)

  1. Updating the CSNS injector linac to 250 MeV with superconducting double-spoke cavities

    International Nuclear Information System (INIS)

    Li Zhihui; Fu Shinian

    2015-01-01

    In order to update the beam power from 100 kW to 500 kW in the China Spallation neutron source (CSNS) Phase Ⅱ, one of the important measures is to replace the 80 m long beam transport line between the present 80 MeV linac injector and the rapid cycling synchrotron (RCS) to another kind of acceleration structure. In this paper, we proposed a scheme based on 324 MHz double-spoke superconducting cavities. Unlike the superconducting elliptical cavity and normal conducting coupled cavity linac (CCL) structure, the double-spoke cavity belongs to the TE mode structure and has a smaller transverse dimension compared with that of the TH mode one. It can work at base frequency as the drift tube Linac (DTL) section, so that the cost and complexity of the RF system will be much decreased, and the behaviors of the beam dynamics are also improved significantly because of the low charge density and larger longitudinal acceptance. Furthermore, because of the relatively longer interactive length between the charged particle and the electromagnetic field per cell, it needs relatively less cell numbers and it has larger velocity acceptance compared with the double frequency TH structures. The superconducting section consists of 14 periods, each of which includes 3 superconducting cavities encapsulated in one cryomodule and a doublet in room temperate. The general considerations on cavity and beam dynamics design are discussed and the main results are presented. (authors)

  2. Cyclotrons as mass spectrometers

    International Nuclear Information System (INIS)

    Clark, D.J.

    1984-04-01

    The principles and design choices for cyclotrons as mass spectrometers are described. They are illustrated by examples of cyclotrons developed by various groups for this purpose. The use of present high energy cyclotrons for mass spectrometry is also described. 28 references, 12 figures

  3. Transport and emittance study for 18 GHz superconducting-ECR ion source at RCNP.

    Science.gov (United States)

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Kibayashi, M; Morinobu, S; Tamii, A

    2012-02-01

    As the upgrade program of the azimuthally varying field (AVF) cyclotron is at the cyclotron facility of the RCNP, Osaka University for the improvement of the quality, stability, and intensity of accelerated beams, an 18 GHz superconducting (SC) ECR ion source has been installed to increase beam currents and to extend the variety of ions, especially for highly charged heavy ions which can be accelerated by RCNP AVF cyclotron. The production development of several ions such as B, O, N, Ne, Ar, Ni, Kr, and Xe has been performed by Yorita et al. [Rev. Sci. Instrum. 79, 02A311(2008); 81, 02A332 (2010)]. Further studies for the beam transport have been done in order to improve the beam current more for injection of cyclotron. The effect of field leakage of AVF main coil is not negligible and additional steering magnet has been installed and then beam transmission has been improved. The emittance monitor has also been developed for the purpose of investigating correlation between emittance of beam from ECR ion sources and injection efficiency. The monitor consists with BPM82 with rotating wire for fast measurement for efficient study.

  4. Superconducting homopolar motor and conductor development

    Science.gov (United States)

    Gubser, Donald U.

    1996-10-01

    The U.S. Navy has been developing superconducting homopolar motors for ship applications since 1969; a successful at-sea demonstration of the first motor, using NbTi wire for the magnet, was achieved in the early 1980s. Recently, this same motor was used as a test bed to demonstrate progress in high-critical-temperature superconducting magnet technology using bismuth-strontium- calcium-copper-oxide (BSCCO) compounds. In the fall of 1995, this motor achieved a performance of 124 kW operating at a temperature of 4.2 K and 91 kW while operating at 28 K. Future tests are scheduled using new magnets with conductors of both the 2223 and the 2212 BSCCO phases. This article describes the advantages of superconducting propulsion and recent progress in the development of BSCCO conductors for use in Navy power systems.

  5. Study of LHW and IBW synergy experiment on the HT-7 superconducting tokamak

    International Nuclear Information System (INIS)

    Gao, X.

    2001-01-01

    A successful experiment on lower hybrid wave (LHW) and ion Bernstein wave (IBW) synergy has been carried out in the HT-7 superconducting tokamak. With 500 kW of LHW heating power and 200 kW of injected IBW power, it is observed that the ion temperature increases from 500 eV to about 850 eV, the electron temperature increases from 800 eV to 1.2 keV, and the averaged electron density increases from 0.9x10 19 m -3 to 2.6x10 19 m -3 . The plasma parameters were obviously enhanced by means of the LHW and IBW heating and their synergy. The charge-exchange spectra of the neutral particle analysis (NPA) diagnostics data clearly showed that the high-energy ion tail which was produced by the LHW was decreased by the synergy with the IBW, and the bulk ion temperature was increased. The mechanism of the LHW and IBW synergy effect is discussed. (author)

  6. Improvement the Capacity of Cockcroft-Walton High Voltage Source from 300 kV/20 mA to 500 kV/20 mA for Accelerating Voltage of Electron Beam Machine

    International Nuclear Information System (INIS)

    Suprapto; Djasiman

    2002-01-01

    The improvement capacity of Cockcroft-Walton high voltage source from 300 kV/20 mA to 500 kV/mA has been carrying out. To improve the capacity of high voltage source was done by means of increasing the stage number of voltage multiplier from 11 to 18 and its output voltage measuring resistance. Each stage of voltage multiplier consists of 2 capacitors and 2 circuits of high voltage diode. This voltage multiplier is constructed using main components of high voltage capacitor and high voltage diode each of 0.22 μF/50 kV and UF 5408 respectively. To avoid stray discharge and corona it was provided with high voltage electrode and corona ring. The test result indicated that the output voltage obtained from 16 stages was 350 kV according to operating condition of 25 MΩ resistive load and first stage voltage of 28.5 kV with oscillator frequency of 24 Hz. That condition requires anode voltage and current of 5.5 kV and 2.5 A respectively. The no load test for 16 stages indicates 400 kV of output voltage and 28.5 kV first stage voltage. Efficiency of high voltage source was 48 % at 6.75 kW of output power. The expected test of 500 kV with 18 stages of voltage multiplier can not be carried out because of some restrictive of loading system. From the test result can be predicted that the output voltage of 500 kV with 18 stages of voltage multiplier requires 31.2 kV of first stage voltage. Then the expected high voltage source of Cockcroft-Walton is capable as accelerating voltage source for Electron Beam Machine with energy of 500 kV. (author)

  7. Neigiamojo standumo vibroizoliacinio staliuko „MINUS K 500BM-1“ tyrimas

    Directory of Open Access Journals (Sweden)

    Vitalija Meškelytė

    2012-01-01

    Full Text Available Nagrinėjamas neigiamojo standumo (angl. negative-stiffness vibroizoliacinio staliuko „Minus K 500BM-1“ efektyvumas 2–110 Hz diapazone. Apžvelgti kiti galimi vibroizoliacijos būdai. Atlikti eksperimentiniai vibracijų perduodamumo tyrimai. Išbandyta speciali vibracijų žadinimo įranga, leidžianti atlikti numatytus bandomojo objekto tyrimus. Aprašyta eksperimentinių tyrimų metodika. Pateikti eksperimentų metu gauti rezultatai ir išvados.

  8. Advanced control system for the scattering chamber of K-130 cyclotron

    International Nuclear Information System (INIS)

    Bhaumik, Tapas Kumar; Saha, Amiya Kumar; Mandal, Bidhan Chandra; Adak, Debabrata; Purkait, Monirul; Bhattacharya, Sailajananda

    2013-01-01

    The old relay based position control system of the Scattering Chamber of K-130 Cyclotron was more than 30 years old, developed multiple problems over the years, and the components of the control system like relays, potentiometers, limit switches, radiation resistant cables were not functioning as per specifications. It has been replaced recently by a new PLC based embedded control system. This has been developed using Advantech ADAM-5510EKW 16 bit CPU together with required I/O modules. MULTIPROG Basic V.4.6 has been used as programming software and Ladder Diagram has been used to realize control scheme of the PLC. A resistive type touch screen based operator panel, WebOP-2104VN4AE has been mounted on the control rack for local control. iFIX SCADA, 75 tags Runtime Version 5.1 has been used to operate from remote PC connected to the PLC by 70m CAT6 cable. The PLC communicates with the touch panel and remote PC through 100 Mbps Ethernet switch. The Graphical User Interfaces of the local control panel and the remote panel have been developed as per the requirement from the users. All the old sensors, limit switches, relays and cables have been replaced by new items. This paper reports about the development and commissioning of basic hardware, software and operation of the control system for last six months. (author)

  9. Investigation of superconducting properties of nanowires prepared by template synthesis

    DEFF Research Database (Denmark)

    Michotte, S.; Mátéfi-Tempfli, Stefan; Piraux, L.

    2003-01-01

    of the nanowires is small enough to ensure a one-dimensional superconducting regime in a wide temperature range below T. The non-zero resistance in the superconducting state and its variation caused by fluctuations of the superconducting order parameter were measured versus temperature, magnetic field, and applied......We report on the transport properties of single superconducting lead nanowires grown by an electrodeposition technique, embedded in a nanoporous track-etched polymer membrane. The nanowires are granular, have a uniform diameter of ∼40 nm and a very large aspect ratio (∼500). The diameter...

  10. Medical applications of cyclotrons

    International Nuclear Information System (INIS)

    Jean, R.; Fauchet, M.

    1978-01-01

    Isochronous cyclotrons used to accelerate different charged particles (protons, deuterons, alphas...) at variable energies, have important medical applications, for neutron teletherapy, in vivo or in vitro activation analysis or production of short-lived radioisotopes for nuclear medicine. The characteristics of the cyclotron presently available are described for these three applications (low energy 'compact' cyclotrons, cyclotrons of intermediate and high energies), and their advantages are discussed from the points of view of the medical requirements, the financial investments and the results obtained. (orig.) [de

  11. On active disturbance rejection based control design for superconducting RF cavities

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, John; Morris, Dan; Usher, Nathan [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, MI 48824-1321 (United States); Gao, Zhiqiang, E-mail: z.gao@csuohio.edu [Center for Advanced Control Technologies, Fenn College of Engineering, Cleveland State University, Cleveland, OH 44115-2214 (United States); Zhao Shen; Nicoletti, Achille; Zheng Qinling [Center for Advanced Control Technologies, Fenn College of Engineering, Cleveland State University, Cleveland, OH 44115-2214 (United States)

    2011-07-01

    Superconducting RF (SRF) cavities are key components of modern linear particle accelerators. The National Superconducting Cyclotron Laboratory (NSCL) is building a 3 MeV/u re-accelerator (ReA3) using SRF cavities. Lightly loaded SRF cavities have very small bandwidths (high Q) making them very sensitive to mechanical perturbations whether external or self-induced. Additionally, some cavity types exhibit mechanical responses to perturbations that lead to high-order non-stationary transfer functions resulting in very complex control problems. A control system that can adapt to the changing perturbing conditions and transfer functions of these systems would be ideal. This paper describes the application of a control technique known as 'Active Disturbance Rejection Control' (ARDC) to this problem.

  12. Co60 and Cs137 gamma radiation effects on textured bscco Superconducting fibers

    International Nuclear Information System (INIS)

    Leyva Fabelo, A.; Bouza Dominguez, J.; Cruz Inclan, Crlos M.

    2001-01-01

    Bi2Sr2CaCu2Ox superconducting fibers synthesized by solid state reaction and textured by the method of zonal laser ablation were irradiated with gamma rays of 1.25 MeV and 662 keV and studied the behavior of some of its properties with the exposition dose. The measurements of dynamic magnetic susceptibility were used for the characterization of the samples. It was observed that for the dose of up to 600 kGy in the case of the Co60 and until 500 mGy for the Cs137, the fibers preserve its superconducting intragrain properties. It is an evidence of the high resistance of the material to the radiacional damage. In all the cases were verified that with the increase of the dose the Ton of the transition grows. Two possible mechanisms that play the most important role in this effect are explained in the text. The ac measurements allowed to verified the increasing behavior of the superconducting volume fraction in the sample with the exposition dose

  13. Technical challenges of superconductivity and cryogenics in pursuing TESLA-TTF

    International Nuclear Information System (INIS)

    Shu, Quan-Sheng

    1996-01-01

    TESLA (TeV Energy Superconducting Linear Accelerator) Collaboration is an international R ampersand D effort towards the development of an e + e - linear collider with 500 GeV center of mass by means of 20 km active superconducting accelerating structures at a frequency of 1.3 GHz. The ultimate challenges faced by the TESLA project are (1) to raise operational accelerating gradients to 25 MV/m from current world level of 5-10 MV/m, and (2) to reduce construction costs (cryomodules, klystrons, etc.) down to $2,000/MV from now about $40,000/MV. The TESLA Collaboration is building a prototype TESLA test facility (TTF) of a 500 MeV superconducting linear accelerator to establish the technical basis. TTF is presently under construction and will be commissioned at DESY in 1997, through the joint efforts of 24 laboratories from 8 countries. Significant progress has been made in reaching the high accelerating gradient of 25 MV/m in superconducting cavities, developing cryomodules and constructing TTF infrastructure, etc. This paper will briefly discuss the challenges being faced and review the progress achieved in the technical area of superconductivity and cryogenics by the TESLA Collaboration

  14. Digital control in LLRF system for CYCIAE-100 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Fu, Xiaoliang; Ji, Bin; Zhang, Tianjue; Wang, Chuan

    2016-05-21

    As a driven accelerator, the CYCIAE-100 cyclotron is designed by China Institute of Atomic Energy for the Beijing Radio Ion-beam Facility project. The cyclotron RF system is designed to use two RF power sources of 100 kW to drive two half-wavelength cavities respectively. Two Dee accelerating electrodes are kept separately from each other inside the cyclotron, while their accelerating voltages are maintained in phase by the efforts of LLRF control. An analog–digital hybrid LLRF system has been developed to achieve cavity tuning control, dee voltage amplitude and phase stabilization etc. The analog subsystems designs are focused on RF signal up/down conversion, tuning control, and dee voltage regulation. The digital system provides an RF signal source, aligns the cavity phases and maintains a Finite State Machine. The digital parts combine with the analog functions to provide the LLRF control. A brief system hardware introduction will be given in this paper, followed by the review of several major characteristics of the digital control in the 100 MeV cyclotron LLRF system. The commissioning is also introduced, and most of the optimization during the process was done by changing the digital parts.

  15. New development of neutron radiography with a small cyclotron

    International Nuclear Information System (INIS)

    Ikeda, Yasushi; Ohkubo, Kohei; Kato, Toshihiko; Nakamura, Tomihisa; Fuji, Takayoshi.

    1990-01-01

    A series of neutron radiography testing has been performed for several years by using a small accelerator called 'Baby Cyclotron' manufactured by Japan Steel Works, Ltd. The Baby Cyclotron produces fast neutrons at the rate of 4x10 12 n/cm 2 s, and enables to perform neutron radiography imaging by various techniques. The most important application of this Baby Cyclotron radiography system is the non-destructive testing (NDT) of various explosive devices prepared for space launch vehicles. It is assured that thermal neutron radiography testing is a very useful means for the NDT. Also fast neutron radiography testing is in progress. The fast neutron radiography with a CR39 track-etch image recorder was developed, and it was shown to be the very useful NDT means when the thicker objects used for new H-2 launch vehicles had to be examined. Because thermal neutron radiography has the high detectability of hydrogenous materials, organic elastomers such as O-rings and explosive powder are clearly observable through the opaque steel walls of containers. The Baby Cyclotron and the neutron radiography facility, thermal neutron and fast neutron radiography testings and so on are reported. (K.I.)

  16. Two-step superconducting transition in Cu-V-Si alloys

    International Nuclear Information System (INIS)

    Sharma, R.G.; Krishna, M.M.; Narlikar, A.V.

    1980-01-01

    Copper ternary alloys containing small amounts of vanadium and silicon exhibit a two-step superconducting resistive transition. The first transition occurs around 17 K, the transition temperature of β-W V 3 Si, followed by a plateau and a second transition around 10 K. The resistivity, however, does not drop to zero down to 2.5 K. Reduction of the wire diameter causes the two transitions to shift to lower temperatures. Complete superconductivity in these specimens is absent for two reasons. Firstly, the superconducting volume fraction present in these alloy-wires is below the threshold given by either the effective-medium theory or the site percolation theory. Secondly, the superconducting phase V 3 Si does not precipitate in copper matrix in a fine structure and the proximity effect does not operate strongly. Annealing causes the superconducting particles to coalesce and grow in size and suppresses the proximity effect and superconductivity further in these alloy wires. (author)

  17. Ion–Cyclotron Resonance Frequency Interval Dependence on the O ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The frequency intervals in which O VI ions get in resonance with ion–cyclotron waves are calculated using the kinetic model, for the latest six values found in literature on O VI ion number densities in the 1.5–3 region of the NPCH. It is found that the common resonance interval is 1.5 kHz to 3 kHz.

  18. Radio frequency system of the RIKEN ring cyclotron

    International Nuclear Information System (INIS)

    Fujisawa, T.; Ogiwara, K.; Kohara, S.; Oikawa, Y.; Yokoyama, I.; Nagase, M.; Takeshita, I.; Chiba, Y.; Kumata, Y.

    1987-01-01

    The radio-frequency(RF) system of the RIKEN ring cyclotron(K = 540) is required to work in a frequency range of 20 to 45 MHz and to generate the maximum acceleration voltage 250 kV. A new movable box type variable frequency resonator was designed for that purpose. The final amplifier is capable to deliver 300 kW. The resonators and the amplifiers have been installed at RIKEN and the performances are studied. The result shows the movable box type resonator and the power amplifier system satisfy the design aim. (author)

  19. Quality assessment of buccal versus blood genomic DNA using the Affymetrix 500 K GeneChip

    Directory of Open Access Journals (Sweden)

    Martin Lisa J

    2007-11-01

    Full Text Available Abstract Background With the advent of genome-wide genotyping, the utility of stored buccal brushes for DNA extraction and genotyping has been questioned. We sought to describe the genomic DNA yield and concordance between stored buccal brushes and blood samples from the same individuals in the context of Affymetrix 500 K Human GeneChip genotyping. Results Buccal cytobrushes stored for ~7 years at -80°C prior to extraction yielded sufficient double stranded DNA (dsDNA to be successfully genotyped on the Affymetrix ~262 K NspI chip, with yields between 536 and 1047 ng dsDNA. Using the BRLMM algorithm, genotyping call rates for blood samples averaged 98.4%, and for buccal samples averaged 97.8%. Matched blood samples exhibited 99.2% concordance, while matched blood and buccal samples exhibited 98.8% concordance. Conclusion Buccal cytobrushes stored long-term result in sufficient dsDNA concentrations to achieve high genotyping call rates and concordance with stored blood samples in the context of Affymetrix 500 K SNP genotyping. Thus, given high-quality collection and storage protocols, it is possible to use stored buccal cytobrush samples for genome-wide association studies.

  20. Design and Fabrication Study on the TESLA500 Superconducting Magnet Package

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Tabares, L.; Toral, F.; Calero, J.; Abramian, P.; Iturbe, R.; Etxeandia, J.; Lucia, C.; Landete, R.; Gomez, J.

    2001-07-01

    An international collaboration at DESY is currently studying the possibilities of a new type of particle accelerator: the superconducting linear collider (1). Developed under the project name TESLA, which stands for TeV Energy Superconducting Linear Accelerator, the facility would be placed in a 33 km long tunnel and would work at the energy range of 0.5 to 0.8 TeV. TESLA opens up new horizons not only as a particle accelerator because it can be also used to generate laser-type X-ray beams: the accelerated electrons would be guided through a refined system of magnetic fields to form a Free Electron Laser (FEL). This study is about one of the components of the accelerator: the magnet package. A technical design of this device and a cost estimate of the series production have been performed. The present report should be understood as a Spanish contribution to the TESLA project. The study has been lead by CIEMAT (Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas) [2], and several Spanish companies have also been involved: ANTEC, JEMA and INGOVI. Special thanks are given to the Oficina de Ciencia y Tecnologia, which has granted this work. (Author) 16 refs.

  1. Design and Fabrication Study on the TESLA500 Superconducting Magnet Package

    International Nuclear Information System (INIS)

    Garcia-Tabares, L.; Toral, F.; Calero, J.; Abramian, P.; Iturbe, R.; Etxeandia, J.; Lucia, C.; Landete, R.; Gomez, J.

    2001-01-01

    An international collaboration at DESY is currently studying the possibilities of a new type of particle accelerator: the superconducting linear collider (1). Developed under the project name TESLA, which stands for TeV Energy Superconducting Linear Accelerator, the facility would be placed in a 33 km long tunnel and would work at the energy range of 0.5 to 0.8 TeV. TESLA opens up new horizons not only as a particle accelerator because it can be also used to generate laser-type X-ray beams: the accelerated electrons would be guided through a refined system of magnetic fields to form a Free Electron Laser (FEL). This study is about one of the components of the accelerator: the magnet package. A technical design of this device and a cost estimate of the series production have been performed. The present report should be understood as a Spanish contribution to the TESLA project. The study has been lead by CIEMAT (Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas) [2], and several Spanish companies have also been involved: ANTEC, JEMA and INGOVI. Special thanks are given to the Oficina de Ciencia y Tecnologia, which has granted this work. (Author) 16 refs

  2. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    Energy Technology Data Exchange (ETDEWEB)

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology (IUST), Tehran (Iran, Islamic Republic of)], E-mail: heydari@iust.ac.ir, E-mail: faramarz_faghihi@ee.iust.ac.ir, E-mail: reza_sharifi@ee.iust.ac.ir, E-mail: amirhosseinp@ee.iust.ac.ir

    2008-09-15

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT.

  3. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    Science.gov (United States)

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein

    2008-09-01

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT.

  4. Superconducting technology for overcurrent limiting in a 25 kA current injection system

    International Nuclear Information System (INIS)

    Heydari, Hossein; Faghihi, Faramarz; Sharifi, Reza; Poursoltanmohammadi, Amir Hossein

    2008-01-01

    Current injection transformer (CIT) systems are within the major group of the standard type test of high current equipment in the electrical industry, so their performance becomes very important. When designing high current systems, there are many factors to be considered from which their overcurrent protection must be ensured. The output of a CIT is wholly dependent on the impedance of the equipment under test (EUT). Therefore current flow beyond the allowable limit can occur. The present state of the art provides an important guide to developing current limiters not only for the grid application but also in industrial equipment. This paper reports the state of the art in the technology available that could be developed into an application of superconductivity for high current equipment (CIT) protection with no test disruption. This will result in a greater market choice and lower costs for equipment protection solutions, reduced costs and improved system reliability. The paper will also push the state of the art by using two distinctive circuits, closed-core and open-core, for overcurrent protection of a 25 kA CIT system, based on a flux-lock-type superconducting fault current limiter (SFCL) and magnetic properties of high temperature superconducting (HTS) elements. An appropriate location of the HTS element will enhance the rate of limitation with the help of the magnetic field generated by the CIT output busbars. The calculation of the HTS parameters for overcurrent limiting is also performed to suit the required current levels of the CIT

  5. A parasitic magnetic refrigerator for cooling superconducting magnet

    International Nuclear Information System (INIS)

    Nakagome, H.; Takahashi, M.; Ogiwara, H.

    1988-01-01

    The application of magnetic refrigeration principle at a liquid helium temperature (4.2K) is very useful for cooling a superconducting magnet for its potential of high efficiency. The magnetic refrigerator equipped with 14 pieces of GGG (gadolinium-gallium-garnet) single crystal unit (30mm in diameter 10mm in length) in the rotating disk operates along the gradient of the magnetic field produced by a racetrack superconducting magnet, whose maximum magnetic field is 4.5 Tesla and the minimum field is 1.1 Tesla. The final goal of their program is to liquefy gaseous helium evaporated from a liquid helium vessel of the racetrack superconducting magnet by the rotating magnetic refrigerator which operates by using the magnetic field of the superconducting magnet. A 0.12W refrigeration power in the 0.72rpm operation has been achieved under condition of 4.2K to 11.5K operation. The helium evaporation rate of this magnet system is estimated as the order of 10mW, and the achieved refrigeration power of 0.12W at 4.2K is sufficient for cooling the superconducting magnet

  6. Superconducting solenoid designed for 400 kJ at 25 kA under conditions of fast discharge and field reversal

    International Nuclear Information System (INIS)

    Weldon, D.; Chowdhuri, P.; Honig, M.; Rogers, J.D.; Thullen, P.

    1981-05-01

    A 1.26-mH superconducting solenoid made of NbTi and Cu-CuNi mixed matrix superconductor was designed and fabricated by Westinghouse Electric Corporation for the Los Alamos National Laboratory as part of the pulsed energy storage coil program. The coil was designed to store 400 kJ at a current of 25 kA and has been operated to currents of 20 kA. Development of high current cables and low-loss superconductors are both necessary undertakings for future fusion devices. The first tests of the coil involved a very slow charge of the coil followed by a rapid discharge in 1.07 ms with a capacitor bank and a normal-conductor load coil in a resonant L-C-L circuit. The second test consisted of a slow charge followed by a discharge and recharge on a time scale of a few seconds. This latter cycle resembles that expected in a tokamak induction coil. Loss measurements were made by an electrical method during the second series of tests

  7. Development of 50 MVA superconducting generator

    International Nuclear Information System (INIS)

    Ueda, Kiyotaka; Maki, Naoki; Takahashi, Noriyoshi; Ogata, Hisanao; Sanematsu, Toshihiro.

    1984-01-01

    Superconducting synchronous generators are expected to be the large capacity turbogenerators of next generation, but they have the structural features considerably different from conventional generators, such as low temperature multiple cylinder rotors and air gap armature winding. For the purpose of grasping the performance of superconducting generators and establishing the fundamental technology for their practical use, Hitachi Ltd. manufactured a 50 MVA superconducting generator. As the results of test, the precooling operation was smoothly finished for about 40 hours, and the superconducting rotor rotated stably at 3000 rpm. The steady and transient electrical characteristics were able to be grasped. It is intended to reflect these results to the development of a practical generator of 500 MVA class expected as the next step. When the superconducting exciting winding cooled by liquid helium is used, the reduction of weight, the improvement of efficiency and the improvement of the stability of power system can be expected. The structural features and the function of superconducting generators, the present state of the development in the world, the outline of the 50 MVA generator, the test results and the problems and the prospect hereafter are reported. The superconducting winding was made of NbTiZr alloy multicore wires. (Kako, I.)

  8. Status of superconducting power transformer development

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.C.; McConnell, B.W.; Mehta, S.P. [and others

    1996-03-01

    Development of the superconducting transformer is arguably the most difficult of the ac power applications of superconductivity - this is because of the need for very low ac losses, adequate fault and surge performance, and the rigors of the application environment. This paper briefly summarizes the history of superconducting transformer projects, reviews the key issues for superconducting transformers, and examines the status of HTS transformer development. Both 630-kVA, three-phase and 1-MVA single phase demonstration units are expected to operate in late 1996. Both efforts will further progress toward the development of economical and performance competitive superconducting transformers.

  9. Superconducting magnet

    Science.gov (United States)

    1985-01-01

    Extensive computer based engineering design effort resulted in optimization of a superconducting magnet design with an average bulk current density of approximately 12KA/cm(2). Twisted, stranded 0.0045 inch diameter NbTi superconductor in a copper matrix was selected. Winding the coil from this bundle facilitated uniform winding of the small diameter wire. Test coils were wound using a first lot of the wire. The actual packing density was measured from these. Interwinding voltage break down tests on the test coils indicated the need for adjustment of the wire insulation on the lot of wire subsequently ordered for construction of the delivered superconducting magnet. Using the actual packing densities from the test coils, a final magnet design, with the required enhancement and field profile, was generated. All mechanical and thermal design parameters were then also fixed. The superconducting magnet was then fabricated and tested. The first test was made with the magnet immersed in liquid helium at 4.2K. The second test was conducted at 2K in vacuum. In the latter test, the magnet was conduction cooled from the mounting flange end.

  10. A high-resolution mK-calorimeter applying SQUID-thermometry

    Energy Technology Data Exchange (ETDEWEB)

    Reifenberger, Andreas; Leps, Norman; Fleischmann, Andreas; Pies, Christian; Enss, Christian; Klingeler, Ruediger [Kirchhoff-Institut fuer Physik, Universitaet Heidelberg, INF 227,69120 Heidelberg (Germany)

    2012-07-01

    A new calorimeter for measuring single-crystalline samples of mg-size at ultra-low temperatures is described. Thermometry is done by means of a paramagnetic sensor material (Er-doped Au) in a low magnetic field. A temperature change results in a magnetization change which can be read out as change in magnetic flux by a superconducting quantum interference device (SQUID). This enables measurements in a wide temperature range (theoretically from 1 mK-1 K) with very high sensitivities. The bolometric design exhibits low addenda heat capacity and allows measurements of heat capacities from nJ/K to {mu}J/K by means of a temperature-relaxation method. The performance of the device is compared to a commercially available Quantum Design calorimeter in elsewise unchanged experimental settings in the temperature range from 15 mK to 500 mK.

  11. Proceedings of the 12. Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Heating

    International Nuclear Information System (INIS)

    Giruzzi, Gerardo

    2003-01-01

    The 12. Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Heating was held in Aix-en-Provence (France) from 13 to 16 May 2002. The meeting was hosted by the Association Euratom-CEA sur la Fusion (CEA/Cadarache, France), with additional financial support from: - Region Provence-Alpes Cote d'Azur - The City of Aix-en-Provence - Communaute de l'Agglomeration du Pays d'Aix - Thales Electron Devices (France) - Alstom Magnets and Superconductors (France) - Spinner GmbH (Germany). The members of the local organizing committee were: G. Giruzzi, M. Lennholm, R. Magne and V. Poli, from CEA/Cadarache. The composition of the International Programme Committee was the following: M. Bornatici (Italy), A. Costley (ITER), E. de la Luna (Spain), G. Giruzzi (France), W. Kasparek (Germany), B. Lloyd (UK), J. Lohr (USA), K. Sakamoto (Japan). The subjects of the meeting were classified in four main topics: Electron Cyclotron Theory; Electron Cyclotron Emission; Electron Cyclotron Heating and Current Drive Experiments; Electron Cyclotron Technology. The results presented in these topics have been summarised in the closing session by E. Westerhof, A. Kraemer-Flecken, T. Goodman and G. Bosia, respectively. The workshop was attended by 85 participants from 18 countries, providing 10 invited talks, 30 oral presentations and 50 posters. The success of the workshop is mainly due to the amount and quality of their work and of their presentations. The generosity of the sponsors, the selection and advice work of the International Programme Committee, as well as the contribution of the chairmen and of the summary speakers should also be warmly acknowledged. The papers in this collection have been reproduced directly from the authors' manuscripts, provided either as camera-ready texts or as pdf files. The constraints on the papers lengths and formats have been kept to a minimum, on purpose. This series of workshops has now reached a good level of maturity, with well established

  12. ECH pre-ionization and assisted startup in the fully superconducting KSTAR tokamak using second harmonic

    International Nuclear Information System (INIS)

    Bae, Y.S.; Joung, M.; Kim, J.H.; Hahn, S.H.; Yoon, S.W.; Yang, H.L.; Kim, W.C.; Oh, Y.K.; England, A.C.; Bak, J.S.; Jeong, J.H.; Park, S.I.; Namkung, W.; Cho, M.H.; Jackson, G.L.

    2009-01-01

    This letter reports on the successful demonstration of the second harmonic electron cyclotron heating (ECH)-assisted startup in the first plasma experiments recently completed in the fully superconducting Korea Superconducting Tokamak Advanced Research (KSTAR) device whose major and minor radii are 1.8 m and 0.5 m, respectively. For the second harmonic ECH-assisted startup, an 84 GHz EC wave at 0.35 MW was launched before the onset of the toroidal electric field of the Ohmic system. And it was observed that this was sufficient to achieve breakdown in the ECH pre-ionization phase, allow burn-through and sustain the plasma during the current ramp with a low loop voltage of 2.0 V and a corresponding toroidal electric field of 0.24 V m -1 at the innermost vacuum vessel wall (R = 1.3 m). This is a lower value than 0.3 Vm -1 which is the maximum electric field in ITER. Due to the limited volt-seconds and the loop voltage of the Ohmic power system, the extended pulse duration of the ECH power up to 180 ms allowed the plasma current to rise up to more than 100 kA with a ramp-up rate of 0.8 MA s -1 . (letter)

  13. Ingledow 500 kV substation : using mixed technology switchgear solutions for replacement

    Energy Technology Data Exchange (ETDEWEB)

    Wallner, C.; Glaubitz, P. [Siemens AG, Munich (Germany); Messinger, T. [British Columbia Transmission Corp., Vancouver, BC (Canada)

    2008-07-01

    The reliability of the 500 kV equipment at the Ingledow substation operated by BC Hydro Transmission System is of critical importance due to the energy interchange with the Bonneville Power Authority in the United States and the major role of the substation in serving the energy needs of British Columbia's densely populated Lower Mainland. Presently, the 500 kV switchyard includes 10 airblast circuit breakers and the associated current transformers which are all approaching their end of service-life. In response to environmental and safety concerns, the British Columbia Transmission Corporation adopted a policy whereby new oil-filled transformers are no longer acceptable, and the replacement of existing oil-filled transformers must be oil-free. The result is that the current transformers must be either bushing-type or sulphur-hexafluoride (SF6) type. The replacement strategies for the substation equipment consider economical, environmental and seismic issues. They have just as strong an influence on the decision process as the technical, operational and reliability aspects for the particular case or switchgear replacement in the transmission system. The Ingledow case demonstrates the advantages of using mixed technology switchgear, with its compact design flowing from gas insulated switchgear (GIS) for replacement of equipment in an outdoor switchyard. The advantages of the MTS in this case offer the possibility of future reconfiguration to improve the system reliability within the existing switchyard space. 3 refs., 5 figs.

  14. 110GHz-500kW long-pulse gyrotron with built-in quasi-optical mode converter

    International Nuclear Information System (INIS)

    Sakamoto, Keishi; Kariya, Tsuyoshi; Hayashi, Ken-ichi.

    1994-01-01

    We have designed, fabricated, and tested a 110 GHz-500 kW long-pulse gyrotron. The gyrotron incorporates a quasi-optical mode converter which transforms the oscillation mode, TE 22,2 , into a Gaussian radiation beam. The adoption of a built-in mode converter enabled us to design the electron beam collector so as to be capable of tolerating a 2 MW heat load. Attention was also paid to designing the gyrotron cavity and output window so as to permit long-pulse operations. In an experiment, we observed a maximum output power of 550 kW and achieved 1.3 s operation at a power level of 410 kW. (author)

  15. High-field superconducting nested coil magnet

    Science.gov (United States)

    Laverick, C.; Lobell, G. M.

    1970-01-01

    Superconducting magnet, employed in conjunction with five types of superconducting cables in a nested solenoid configuration, produces total, central magnetic field strengths approaching 70 kG. The multiple coils permit maximum information on cable characteristics to be gathered from one test.

  16. SATDSK: a numerical simulation of the magnetic field due to saturated iron in cyclotron poletips

    International Nuclear Information System (INIS)

    McNeilly, G.S.

    1979-10-01

    SATDSK is a computer program, written in FORTRAN, which calculates the median plane magnetic field due to fully saturated iron poletips. Optionally, SATDSK calculates the magnetic field due to disks of magnetic charge, which can simulate the effect of holes in the iron poletip, or circular trim rods embedded in the poletip. SATDSK is intended for poletip geometries that are both symmetric about the median plane, and have azimuthal sector symmetry. Thus, the program is primarily designed to simulate the magnetic field due to iron poletips in superconducting cyclotrons

  17. 500 keV, 10 kW DC electron accelerator at BRIT, Vashi

    International Nuclear Information System (INIS)

    Sharma, D.K.; Rajan, R.N.; Bakhtsingh, R.I.; Acharya, S.; Rajawat, R.K.

    2017-01-01

    The 500 keV DC accelerator was indigenously designed and developed by Accelerator and Pulse Power Division, BARC during 1994-97 and commissioned at REPF Hall, BRIT, Vashi on 10"t"h August, 1998. The accelerator operation at 3kW beam power for 8 hour shifts was established in February 2001, confirming to industrial standards for EB treatment of plastic sheets as well as various surface-treatment processes for value addition of the products and materials. Since then, this EB facility is functional and being regularly utilized for various applications

  18. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron

  19. Superconducting magnets for HERA

    International Nuclear Information System (INIS)

    Wolff, S.

    1987-01-01

    The Hadron-Electron-Ring Accelerator (HERA) presently under construction at DESY, Hamburg, consists of an electron storage ring of 30 GeV and a proton storage ring of 820 GeV. Superconducting magnets are used for the proton ring. There are 416 superconducting bending magnets of 4.698 T central field and 8.824 m magnetic length, 224 superconducting quadrupoles of 91.2 T/m central gradient and many superconducting correction dipoles, quadrupoles and sextupoles. The main dipoles and quadrupoles consist of two-layer coils of 75 mm inner diameter clammed with aluminium (for the dipoles) or stainless steel laminations (for the quadrupoles). The collared coils are surrounded by a laminated cold iron yoke and supported inside a low loss cryostat. The protection system uses cold diodes to bypass the current around a quenching magnet. The magnets are cooled with one phase helium supplied by a 3 block central refrigeration system of 20 kW refrigeration power at 4.3 K. Two helium is returned through the magnets in good thermal contact with the one phase helium in the dipoles for temperature control. This paper describes the magnet system and gives the results obtained for prototype magnets

  20. Coupling between magnetic and superconducting order parameters and evidence for the spin excitation gap in the superconducting state of a heavy fermion superconductor UPd2Al3

    International Nuclear Information System (INIS)

    Metoki, Naoto; Haga, Yoshinori; Koike, Yoshihiro; Aso, Naofumi; Onuki, Yoshichika

    1997-01-01

    Neutron scattering experiments have been carried out in order to study the interplay between magnetism and superconductivity in a heavy fermion superconductor, UPd 2 Al 3 . We have observed 1% suppression of the (0 0 0.5) magnetic peak intensity below the superconducting transition temperature T c . This is direct evidence for the coupling of the magnetic order parameter with the superconducting one. Furthermore, we have observed a spin excitation gap associated with superconductivity. The gap energy ΔE g increases continuously from ΔE g =0 to 0.4 meV with decreasing temperature from T c to 0.4 K. This gap energy corresponds to 2k B T c , which is smaller than the superconducting gap expected from the BCS theory (3.5k B T c ). These results are indicative of the strong interplay between magnetism and superconductivity. (author)

  1. Cyclotrons as Drivers for Precision Neutrino Measurements

    International Nuclear Information System (INIS)

    Alonso, J.; Barletta, W. A.; Winslow, L. A.; Shaevitz, M. H.; Spitz, J.; Conrad, J. M.; Toups, M.; Adelmann, A.

    2014-01-01

    As we enter the age of precision measurement in neutrino physics, improved flux sources are required. These must have a well defined flavor content with energies in ranges where backgrounds are low and cross-section knowledge is high. Very few sources of neutrinos can meet these requirements. However, pion/muon and isotope decay-at-rest sources qualify. The ideal drivers for decay-at-rest sources are cyclotron accelerators, which are compact and relatively inexpensive. This paper describes a scheme to produce decay-at-rest sources driven by such cyclotrons, developed within the DAEδALUS program. Examples of the value of the high precision beams for pursuing Beyond Standard Model interactions are reviewed. New results on a combined DAEδALUS—Hyper-K search for CP violation that achieve errors on the mixing matrix parameter of 4° to 12° are presented

  2. Superconducting tin core fiber

    International Nuclear Information System (INIS)

    Homa, Daniel; Liang, Yongxuan; Hill, Cary; Kaur, Gurbinder; Pickrell, Gary

    2015-01-01

    In this study, we demonstrated superconductivity in a fiber with a tin core and fused silica cladding. The fibers were fabricated via a modified melt-draw technique and maintained core diameters ranging from 50-300 microns and overall diameters of 125-800 microns. Superconductivity of this fiber design was validated via the traditional four-probe test method in a bath of liquid helium at temperatures on the order of 3.8 K. The synthesis route and fiber design are perquisites to ongoing research dedicated all-fiber optoelectronics and the relationships between superconductivity and the material structures, as well as corresponding fabrication techniques. (orig.)

  3. Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes

    Science.gov (United States)

    Lin, He; Yao, Chao; Zhang, Xianping; Zhang, Haitao; Wang, Dongliang; Zhang, Qianjun; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo

    2014-03-01

    Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 104 A/cm2 in 10 T and 4.3 × 104 A/cm2 in 14 T at 4.2 K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications.

  4. Status report on RIKEN Ring Cyclotron

    International Nuclear Information System (INIS)

    Yano, Y.

    1988-01-01

    This paper gives a status report on RIKEN Ring Cyclotron (RRC), successfully commissioned on December 16, 1986. The routine operation of RRC began in April, 1987, and was made until March 1988. April and May were devoted to the machine studies, and beams were delivered to the experiments from the end of May. Seven kinds of ion species from carbon to copper were used for the nuclear physics and atomic physics experiments during these one-year runs. High quality beams with transverse emittances less than 10 mm mrad, energy spread of approximately 0.1% and pulse width less than 300 psec were extracted. Since the middle of March, 1988, RRC has been shut down for extending the beam transfer lines and installing the various experimental setups. Next experimental program will start in July, 1988. The initial operational status of RRC is described as well as the running construction program of the new injector, a K70 AVF cyclotron with an external ECR ion source

  5. Radiation protection of cyclotron vault with maze in PET Cyclotron Center

    International Nuclear Information System (INIS)

    Fueloep, Marko

    2003-01-01

    The PET Cyclotron center (PCC) is a complex for production, research and application of positron radiopharmaceuticals for PET (Positron Emission Tomography), which was commissioned this year (2004) in Bratislava, Slovak Republic. Positron radionuclides are produced by 18/9 MeV proton/deuteron cyclotron CYCLONE 18/9. Radiation protection of personnel and inhabitants against ionizing radiation in the PCC is solved with regard to the ICRP recommendations and Slovak regulatory system, protection rules and criteria and optimization of radiation protection. In the article comparisons of calculated and measured neutron and gamma dose equivalent rates around the CYCLONE 18/9 and at various points behind the shielding of cyclotron vault with maze are presented. Description of the CYCLONE 18/9 as a source of angular distribution of neutron energy spectra (production of 18 F was considered) was simulated by Monte Carlo code MCNPX. Code MCNP4B was used for shielding calculation of cyclotron vault with maze. Neutron energy spectra behind the shielding were measured by Bonner spectrometer. The values of neutron dose equivalent, which were calculated and measured around the CYCLONE 18/9 and at various points behind the shielding of cyclotron vault with maze, are within the range of factor 2. (authors)

  6. Test equipment for a flywheel energy storage system using a magnetic bearing composed of superconducting coils and superconducting bulks

    International Nuclear Information System (INIS)

    Ogata, M; Matsue, H; Yamashita, T; Hasegawa, H; Nagashima, K; Maeda, T; Matsuoka, T; Mukoyama, S; Shimizu, H; Horiuchi, S

    2016-01-01

    Energy storage systems are necessary for renewable energy sources such as solar power in order to stabilize their output power, which fluctuates widely depending on the weather. Since ‘flywheel energy storage systems’ (FWSSs) do not use chemical reactions, they do not deteriorate due to charge or discharge. This is an advantage of FWSSs in applications for renewable energy plants. A conventional FWSS has capacity limitation because of the mechanical bearings used to support the flywheel. Therefore, we have designed a superconducting magnetic bearing composed of a superconducting coil stator and a superconducting bulk rotor in order to solve this problem, and have experimentally manufactured a large scale FWSS with a capacity of 100 kWh and an output power of 300 kW. The superconducting magnetic bearing can levitate 4 tons and enables the flywheel to rotate smoothly. A performance confirmation test will be started soon. An overview of the superconducting FWSS is presented in this paper. (paper)

  7. Development of superconducting links for the Large Hadron Collider machine

    Science.gov (United States)

    Ballarino, Amalia

    2014-04-01

    In the framework of the upgrade of the Large Hadron Collider (LHC) machine, new superconducting lines are being developed for the feeding of the LHC magnets. The proposed electrical layout envisages the location of the power converters in surface buildings, and the transfer of the current from the surface to the LHC tunnel, where the magnets are located, via superconducting links containing tens of cables feeding different circuits and transferring altogether more than 150 kA. Depending on the location, the links will have a length ranging from 300 m to 500 m, and they will span a vertical distance of about 80 m. An overview of the R&D program that has been launched by CERN is presented, with special attention to the development of novel types of cables made from MgB2 and high temperature superconductors (Bi-2223 and REBCO) and to the results of the tests performed on prototype links. Plans for future activities are presented, together with a timeline for potential future integration in the LHC machine.

  8. Development of superconducting links for the Large Hadron Collider machine

    CERN Document Server

    Ballarino, A

    2014-01-01

    In the framework of the upgrade of the Large Hadron Collider (LHC) machine, new superconducting lines are being developed for the feeding of the LHC magnets. The proposed electrical layout envisages the location of the power converters in surface buildings, and the transfer of the current from the surface to the LHC tunnel, where the magnets are located, via superconducting links containing tens of cables feeding different circuits and transferring altogether more than 150 kA. Depending on the location, the links will have a length ranging from 300 m to 500 m, and they will span a vertical distance of about 80 m. An overview of the R&D program that has been launched by CERN is presented, with special attention to the development of novel types of cables made from MgB 2 and high temperature superconductors (Bi-2223 and REBCO) and to the results of the tests performed on prototype links. Plans for future activities are presented, together with a timeline for potential future integration in the LHC machine.

  9. Superconducting wires and methods of making thereof

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xingchen; Sumption, Michael D.; Peng, Xuan

    2018-03-13

    Disclosed herein are superconducting wires. The superconducting wires can comprise a metallic matrix and at least one continuous subelement embedded in the matrix. Each subelement can comprise a non-superconducting core, a superconducting layer coaxially disposed around the non-superconducting core, and a barrier layer coaxially disposed around the superconducting layer. The superconducting layer can comprise a plurality of Nb.sub.3Sn grains stabilized by metal oxide particulates disposed therein. The Nb.sub.3Sn grains can have an average grain size of from 5 nm to 90 nm (for example, from 15 nm to 30 nm). The superconducting wire can have a high-field critical current density (J.sub.c) of at least 5,000 A/mm.sup.2 at a temperature of 4.2 K in a magnetic field of 12 T. Also described are superconducting wire precursors that can be heat treated to prepare superconducting wires, as well as methods of making superconducting wires.

  10. High-Tc superconductivity of Tl-Ba-Ca-Cu-O samples

    International Nuclear Information System (INIS)

    Porjesz, T.; Kirschner, I.; Kovacs, G.

    1988-08-01

    A TlBaCaCuO 4.5+x compound has been investigated from the point of view of superconductivity. Depending on the heat treatment, one part of the sample exhibits superconductivity with an onset of 121 K and zero resistivity of 106 K and the other part of them shows a sharp drop in resistivity at 130 K which hints at an existence of superconducting grains. This picture was confirmed by magnetic and ESR measurements giving possibility for estimation of critical magnetic fields. (author). 5 refs, 6 figs

  11. Medical cyclotron: why, where, how

    International Nuclear Information System (INIS)

    Scheer, Kurt; Comar, Dominique; Kellershohn, Claude

    1976-01-01

    Cyclotrons for medical purposes are particularly useful for the production of radioactive isotopes of elements normally constituting organic matter ( 15 O, 13 N, 11 C). The short half-life and positron emission of those elements are of great interest in medical diagnosis. Many others carrier-free radioisotopes can be produced by cyclotrons. Three categories of cyclotrons are mentioned. Desk top cyclotron only adapted to the production of short-lived radioisotopes in a hospital; low energy and average energy cyclotrons which require well-entrained personnel for their operation and are best adapted to the production of radioelements on a regional or even national scale. Examples relative to the interest of short-lived radioisotopes in lung and brain investigations and tumor detection are given

  12. Overview of superconductivity in Japan Strategy road map and R&D status

    Science.gov (United States)

    Tsukamoto, O.

    2008-09-01

    Superconducting technology benefits society in broad fields; environment/energy, life science, manufacturing industry and information and communication. Superconducting equipments and devices used in various fields are divided into two categories, electric and electronic applications. Technologies in those applications are progressing remarkably owing to firm and consistent supports by various national projects. The final target of the NEDO R&D project of fundamental technology for superconductivity applications to develop 500 m long coated conductors (CCs) of the critical current 300 A/cm (at 77 K, 0 T) will be fulfilled by the end of JFY 2007 and manufacturing process to produce extremely low-cost CCs is to be developed to make the applications realistic. Preliminary works to develop power apparatuses using CCs have started in the frame of the R&D project for the fundamental technology and have produced significant results. Performance of BSCCO/Ag-sheathed wires has been improved greatly and various applications using those wires are being developed. R&D projects for SMES, power cable, flywheel energy storage and rotating machines are going to introduce those equipments to the real world. Technologies of SQUID and SFQ, basic devices of the electronic applications, are progressing dramatically also owing to various national projects. In this back ground the technology strategy map in the field of superconducting technology was formulated to prioritize investments in R&D by clearly defining the objectives and inspire autonomous R&D actives in various fields of industries. R&D activities in the superconducting technologies are to be scheduled following this strategy map.

  13. Cyclotrons for isotope production

    International Nuclear Information System (INIS)

    Milton, B.F.; Stevenson, N.R.

    1995-06-01

    Cyclotrons continue to be efficient accelerators for radioisotope production. In recent years, developments in the accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicates a strong future for commercial cyclotrons. In this paper we will survey recent developments in the areas of cyclotron technology, and isotope production, as they relate to the new generation of commercial cyclotrons. We will also discuss the possibility of systems capable of extracted energies up to 100 MeV and extracted beam currents of up to 2.0 mA. (author). 6 refs., 2 tabs., 3 figs

  14. Three-terminal superconducting devices

    International Nuclear Information System (INIS)

    Gallagher, W.J.

    1985-01-01

    The transistor has a number of properties that make it so useful. The authors discuss these and the additional properties a transistor would need to have for high performance applications at temperatures where superconductivity could contribute advantages to system-level performance. These properties then serve as criteria by which to evaluate three-terminal devices that have been proposed for applications at superconducting temperatures. FETs can retain their transistor properties at low temperatures, but their power consumption is too large for high-speed, high-density cryogenic applications. They discuss in detail why demonstrated superconducting devices with three terminals -Josephson effect based devices, injection controlled weak links, and stacked tunnel junction devices such as the superconducting transistor proposed by K. Gray and the quiteron -- each fail to have true transistor-like properties. They conclude that the potentially very rewarding search for a transistor compatible with superconductivity in high performance applications must be in new directions

  15. High-Density Superconducting Cables for Advanced ACTPol

    Science.gov (United States)

    Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-07-01

    Advanced ACTPol (AdvACT) is an upcoming Atacama Cosmology Telescope (ACT) receiver upgrade, scheduled to deploy in 2016, that will allow measurement of the cosmic microwave background polarization and temperature to the highest precision yet with ACT. The AdvACT increase in sensitivity is partly provided by an increase in the number of transition-edge sensors (TESes) per array by up to a factor of two over the current ACTPol receiver detector arrays. The high-density AdvACT TES arrays require 70 \\upmu m pitch superconducting flexible cables (flex) to connect the detector wafer to the first-stage readout electronics. Here, we present the flex fabrication process and test results. For the flex wiring layer, we use a 400-nm-thick sputtered aluminum film. In the center of the cable, the wiring is supported by a polyimide substrate, which smoothly transitions to a bare (uncoated with polyimide) silicon substrate at the ends of the cable for a robust wedge wire-bonding interface. Tests on the first batch of flex made for the first AdvACT array show that the flex will meet the requirements for AdvACT, with a superconducting critical current above 1 mA at 500 mK, resilience to mechanical and cryogenic stress, and a room temperature yield of 97 %.

  16. Isochronous cyclotron data base description

    International Nuclear Information System (INIS)

    Kiyan, I.N.; Vorozhtsov, S.B.; Tarashkevich, R.

    2004-01-01

    The relational data base of the control parameters of the isochronous cyclotron, Isochronous Cyclotron Data Base (ICDB), is described. The relational data base under consideration, written in Transact SQL for the MS SQL Server 2000 with the use of MS Enterprise Manager and MS Query Analyzer, was installed on the server of the AIC144 isochronous cyclotron in Krakow, which operates under the control of the operating system MS Windows Server 2003 (Standard Edition). The interface of the data base under considerations is written in C++ with the use of Visual C++ .NET and is built in the Cyclotron Operator Help Program (COHP), which is used for modeling the operational modes of the isochronous cyclotron. Communication between the COHP and the relational data base is realised on the base of the Open Data Base Connectivity protocol. The relational data base of the control parameter of the isochronous cyclotron is intended: firstly, for systematization and automatic use of all measured and modelled magnetic field maps in the process of modeling the operational modes; secondly, for systematization and convenient access to the stored operational modes; thirdly, for simplifying the operator's work. The relational data base of the control parameter of the isochronous cyclotron reflects its physical structure and the logic of its operator's work. (author)

  17. Loss and Inductance Investigation in Superconducting Cable Conductors

    DEFF Research Database (Denmark)

    Olsen, Søren Krüger; Tønnesen, Ole; Træholt, Chresten

    1999-01-01

    An important parameter in the design and optimization of a superconducting cable conductor is the control of the current distribution among single tapes and layers. This distribution is to a large degree determined by inductances, since the resistances are low. The self and mutual inductances...... of transport current and current distribution.This presentation is based on a number of experiments performed on prototype superconducting cable conductors. The critical current (1uV/cm) of the conductor at 77K was 1590 A (cable #1) and 3240 A (cable #2) respectively.At an rms current of 2 kA (50 Hz) the AC......-loss was measured on cable #2 to 0.6W/mxphase. This is, to our knowledge, the lowest AC-loss (at 2kA and 77K) of a high temperature superconducting cable conductor reported so far....

  18. Status of RF superconductivity at Argonne

    International Nuclear Information System (INIS)

    Shepard, K.W.

    1990-01-01

    Development of a superconducting slow-wave structures began at Argonne National Laboratory (ANL) in 1971, and led to the first superconducting heavy-ion linac (ATLAS - the Argonne Tandem-Linac Accelerator System). The Physics Division at ANL has continued to develop superconducting RF technology for accelerating heavy-ions, with the result that the linac has been in an almost continuous process of upgrade and expansion. In 1987, the Engineering Physics Division at ANL began developing of superconducting RF components for the acceleration of high-brightness proton and deuterium beams. The two divisions collaborate in work on several applications of RF superconductivity, and also in work to develop the technology generally. The present report briefly describes major features of the superconducting heavy-ion linac (very-low-velocity superconducting linac, positive ion injector), proton accelerating structures (superconducting resonant cavities for acceleration of high-current proton and deuteron beams, RF properties of oxide superconductors), and future work. Both divisions expect to continue a variety of studies, frequently in collaboration, to advance the basic technology of RF superconductivity. (N.K.)

  19. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry at the Cyclotron Frequency.

    Science.gov (United States)

    Nagornov, Konstantin O; Kozhinov, Anton N; Tsybin, Yury O

    2017-04-01

    The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω + ), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω + quantity. Here, we describe an experimental observation of a new resonant state, which is located close to the ω c frequency and is established because of azimuthally-dependent trapping electric fields of the recently developed ICR cells with narrow aperture detection electrodes. We show that in mass spectra, peaks close to ω + frequencies can be reduced to negligible levels relative to peaks close to ω c frequencies. Due to reduced errors with which the ω c quantity is obtained, the new resonance provides a means of cyclotron frequency measurements with precision greater than that achieved when ω + frequency peaks are employed. The described phenomenon may be considered for a development into an FT-ICR MS technology with increased mass accuracy for applications in basic research, life, and environmental sciences. Graphical Abstract ᅟ.

  20. Superconductivity in doped Dirac semimetals

    Science.gov (United States)

    Hashimoto, Tatsuki; Kobayashi, Shingo; Tanaka, Yukio; Sato, Masatoshi

    2016-07-01

    We theoretically study intrinsic superconductivity in doped Dirac semimetals. Dirac semimetals host bulk Dirac points, which are formed by doubly degenerate bands, so the Hamiltonian is described by a 4 ×4 matrix and six types of k -independent pair potentials are allowed by the Fermi-Dirac statistics. We show that the unique spin-orbit coupling leads to characteristic superconducting gap structures and d vectors on the Fermi surface and the electron-electron interaction between intra and interorbitals gives a novel phase diagram of superconductivity. It is found that when the interorbital attraction is dominant, an unconventional superconducting state with point nodes appears. To verify the experimental signature of possible superconducting states, we calculate the temperature dependence of bulk physical properties such as electronic specific heat and spin susceptibility and surface state. In the unconventional superconducting phase, either dispersive or flat Andreev bound states appear between point nodes, which leads to double peaks or a single peak in the surface density of states, respectively. As a result, possible superconducting states can be distinguished by combining bulk and surface measurements.

  1. Superconducting active impedance converter

    International Nuclear Information System (INIS)

    Ginley, D.S.; Hietala, V.M.; Martens, J.S.

    1993-01-01

    A transimpedance amplifier for use with high temperature superconducting, other superconducting, and conventional semiconductors allows for appropriate signal amplification and impedance matching to processing electronics. The amplifier incorporates the superconducting flux flow transistor into a differential amplifier configuration which allows for operation over a wide temperature range, and is characterized by high gain, relatively low noise, and response times less than 200 picoseconds over at least a 10-80 K. temperature range. The invention is particularly useful when a signal derived from either far-IR focal plane detectors or from Josephson junctions is to be processed by higher signal/higher impedance electronics, such as conventional semiconductor technology. 12 figures

  2. New 30 kA power system at Fermilab and its use for measuring the effects of ripple current on the performance of superconducting high field magnets

    Energy Technology Data Exchange (ETDEWEB)

    Carcagno, R.; Feher, S.; Garvey, J.; Jaskierny, W.; Lamm, M.; Makulski, A.; Orris, D.F.; Pfeffer, H.; Tartaglia, M.; Tompkins, J.; Wolff, D.; /Fermilab

    2004-12-01

    A new 30 kA, 30 V dc Power System was designed, built, and commissioned at Fermilab for testing Superconducting High Field Magnets. This system has been successfully supporting operations at the Fermilab Magnet Test Facility since April 2002. It is based on six commercial 150 kW Power Energy Industries power supply modules and the following in-house modules: six 720 Hz filters, two 15 kA/1kV dc solid-state dump switch, and a 3 MJ/30 kA/1 kV dc dump resistor. Additional inhouse electronic components were designed and built to provide precise current regulation and distribution of current and current rate of change. An industrial-type Programmable Logic Controller system was used to provide equipment interlocks and monitoring. This paper summarizes studies on the influence of characteristics of this new power system--such as ripple current--on the performance of High Field Superconducting magnets.

  3. New 30 kA power system at Fermilab and its use for measuring the effects of ripple current on the performance of superconducting high field magnets

    International Nuclear Information System (INIS)

    Carcagno, R.; Feher, S.; Garvey, J.; Jaskierny, W.; Lamm, M.; Makulski, A.; Orris, D.F.; Pfeffer, H.; Tartaglia, M.; Tompkins, J.; Wolff, D.

    2004-01-01

    A new 30 kA, 30 V dc Power System was designed, built, and commissioned at Fermilab for testing Superconducting High Field Magnets. This system has been successfully supporting operations at the Fermilab Magnet Test Facility since April 2002. It is based on six commercial 150 kW Power Energy Industries power supply modules and the following in-house modules: six 720 Hz filters, two 15 kA/1kV dc solid-state dump switch, and a 3 MJ/30 kA/1 kV dc dump resistor. Additional in-house electronic components were designed and built to provide precise current regulation and distribution of current and current rate of change. An industrial-type Programmable Logic Controller system was used to provide equipment interlocks and monitoring. This paper summarizes studies on the influence of characteristics of this new power system--such as ripple current--on the performance of High Field Superconducting Magnets

  4. Anomalous superconductivity in black phosphorus under high pressures

    International Nuclear Information System (INIS)

    Kawamura, H.; Tachikawa, K.

    1984-01-01

    Pressure induced superconductivity in single crystals of black phosphorus has been studied. Maximum onset Tsub(c) was near 13 K. The anomalous superconductivity may be explained in terms of excitonic mechanism. (author)

  5. The energizing of a NMR superconducting coil by a superconducting rectifier

    International Nuclear Information System (INIS)

    Sikkenga, J.; ten Kate, H.H.J.; van der Klundert, L.J.M.; Knoben, J.; Kraaij, G.J.; Spuorenberg, C.J.G.

    1985-01-01

    NMR magnets require a good homogeneity within a certain volume and an excellent field stability. The homogeneity can be met using a superconducting shim coil system. The field stability requires a constant current, although in many cases the current decay time constant is too low, due to imperfections in the superconducting wire and joints. This can be overcome using a rectifier. The rectifier can also be used to load the coil. The combination and interaction of the superconducting NMR coil (2.0 Tesla and 0.35 m cold bore) and the rectifier (20 W / 1 kA) is tested. The safety of the system is discussed. The shim coil system can compensate the strayfield of the rectifier. The field decay compensation will be discussed

  6. An overview of accelerator activities at VECC

    International Nuclear Information System (INIS)

    Sinha, Bikash

    2005-01-01

    A superconducting cyclotron with K bend =520 is under construction at this centre. Heavy-ion beams of 80 MeV/nucleon energy for light ions will be available from this cyclotron. Fabrication and development of most of the major systems have advanced significantly. The superconducting cyclotron will become a national facility for various universities and institutes. It will also be open to the international experimental physics community. The room temperature cyclotron at Kolkata is now delivering heavy ion beams. Recently the beams have been utilised by several institutions using clover detectors which is a joint collaborative effort of different institutions. In very near future the cyclotron will be used as primary source for Radioactive Ion Beam (RIB) Facility. Recently alpha and proton beams have been developed using the external ECR ion source. The RIB facility is under construction phase and several components have been installed already. The status of this facility will be described. Preliminary studies regarding the Accelerator Driven System (ADS) using cyclotron as an option to achieve high current proton beam has been undertaken at the centre and the project has been financed. (author)

  7. Medical cyclotron facilities

    International Nuclear Information System (INIS)

    1984-09-01

    This report examines the separate proposals from the Austin Hospital and the Australian Atomic Energy Commission for a medical cyclotron facility. The proponents have argued that a cyclotron facility would benefit Australia in areas of patient care, availability and export of radioisotopes, and medical research. Positron emission tomography (PET) and neutron beam therapy are also examined

  8. Experimental investigation on electron cyclotron absorption at down-shifted frequency in the PLT tokamak

    International Nuclear Information System (INIS)

    Mazzucato, E.; Fidone, I.; Cavallo, A.; von Goeler, S.; Hsuan, H.

    1986-05-01

    The absorption of 60 GHz electron cyclotron waves, with the extraordinary mode and an oblique angle of propagation, has been investigated in the PLT tokamak in the regime of down-shifted frequencies. The production of energetic electrons, with energies of up to 300 to 400 keV, peaks at values of toroidal field (approx. =29 kG) for which the wave frequency is significantly smaller than the electron cyclotron frequency in the whole plasma region. The observations are consistent with the predictions of the relativistic theory of electron cyclotron damping at down-shifted frequency. Existing rf sources make this process a viable method for assisting the current ramp-up, and for heating the plasma of present large tokamaks

  9. Current leads for superconducting solenoids in a transportable Dewar flask for currents up to 1kA

    International Nuclear Information System (INIS)

    Shirshov, L.S.

    1981-01-01

    A simple design of the current lead for currents up to 1 kA into a transportable helium dewar with 22 mm neck diameter is described. The lead characteristics have been studied at various conditions. Examples of pulse superconducting solenoid usage, parmitting to achieve the magnetic field up to 3.3 T are given. The 1% field homogeneity has been obtained on a length of 90 mm [ru

  10. Optical photon detection in Al superconducting tunnel junctions

    International Nuclear Information System (INIS)

    Brammertz, G.; Peacock, A.; Verhoeve, P.; Martin, D.; Venn, R.

    2004-01-01

    We report on the successful fabrication of low leakage aluminium superconducting tunnel junctions with very homogeneous and transparent insulating barriers. The junctions were tested in an adiabatic demagnetisation refrigerator with a base temperature of 35 mK. The normal resistance of the junctions is equal to ∼7 μΩ cm 2 with leakage currents in the bias voltage domain as low as 100 fA/μm 2 . Optical single photon counting experiments show a very high responsivity with charge amplification factors in excess of 100. The total resolving power λ/Δλ (including electronic noise) for 500 nm photons is equal to 13 compared to a theoretical tunnel limited value of 34. The current devices are found to be limited spectroscopically by spatial inhomogeneities in the detectors response

  11. Synthesis of Bulk Superconducting Magnesium Diboride

    Directory of Open Access Journals (Sweden)

    Margie Olbinado

    2002-06-01

    Full Text Available Bulk polycrystalline superconducting magnesium diboride, MgB2, samples were successfully prepared via a one-step sintering program at 750°C, in pre Argon with a pressure of 1atm. Both electrical resistivity and magnetic susceptibility measurements confirmed the superconductivity of the material at 39K, with a transition width of 5K. The polycrystalline nature, granular morphology, and composition of the sintered bulk material were confirmed using X-ray diffractometry (XRD, scanning electron microscopy (SEM, and energy dispersive X-ray analysis (EDX.

  12. First tests of twisted-pair HTS 1 kA range cables for use in superconducting links

    CERN Document Server

    Ballarino, A; Hurte, J; Sitko, M; Willering, G

    2011-01-01

    The requirement at CERN for 1 kA range High Temperature Superconducting (HTS) cables optimized for long electrical transfer has led to the design and assembly of a novel type of cable that can be made from pre-reacted MgB2, Bi-2223 or YBCO tapes. The cable consists of an assembly of twisted pairs, each of which is made from three superconducting tapes with the required copper stabilizer. The twisted pair cable is designed to transfer a DC current of ± 600 A in helium gas environment. The paper reports on the results of the electrical tests performed on twisted-pair cables of identical structure and made from commercially available MgB2, Bi-2223 and YBCO tapes. The twist pitch of the cables is adapted to match the mechanical properties of the different superconductors. Critical current tests were performed at both liquid helium and liquid nitrogen temperature. The electrical performance of several cables made from different conductors is reported and compared.

  13. Two gap superconductivity in Ba0.55K0.45Fe2As2 single crystals studied by the directional point-contact Andreev reflection spectroscopy

    International Nuclear Information System (INIS)

    Szabo, P.; Pribulova, Z.; Pristas, G.; Bud'ko, S.L.; Canfield, P.C.; Samuely, P.

    2009-01-01

    First directional point-contact Andreev reflection spectroscopy on the Ba 0.55 K 0.45 Fe 2 As 2 single crystals is presented. The spectra show significant differences when measured in the ab plane in comparison with those measured in the c direction. In the latter case no traces of superconducting energy gap could be found, just a reduced point-contact conductance persisting up to about 100 K and indicating reduced density of states. On the other hand within the ab plane two nodeless superconducting energy gaps Δ S ∼2-5 meV and Δ L ∼9-11 meV are detected.

  14. Development of Medical Cyclotron in KIRAMS

    International Nuclear Information System (INIS)

    Chai, Jong Seo; Jung, In Su; An, Dong Hyun

    2005-01-01

    This paper is presented on the development and status of medical cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS) at present. We have developed medical cyclotron which is KIRAMS-13. And the improvement of KIRAMS-13 is presented. Furthermore, the design of new cyclotrons, such as KIRAMS-5 and KIRAMS-30 cyclotron, are presented, and R and D studies for future plan of heavy ion accelerator are discussed

  15. Superconducting permanent magnets and their application in magnetic levitation

    International Nuclear Information System (INIS)

    Schultz, L.; Krabbes, G.; Fuchs, G.; Pfeiffer, W.; Mueller, K.H.

    2002-01-01

    Superconducting permanent magnets form a completely new class of permanent magnets. Of course, they must be cooled to 77 K or below. At very low temperatures (24 K) their magnetization can be a factor of 10 higher than that of the best conventional magnets, providing magnetic forces and energies which are up to two orders of magnitude higher. These new supermagnets became only recently available by the extreme improvement of the quality of melt-textured massive YBa 2 Cu 3 O x samples. Besides having a high magnetization, these superconducting permanent magnets can freeze in any given magnetic field configuration allowing completely new applications like superconducting transport systems or superconducting magnetic bearings. (orig.)

  16. Study of superconducting magnetic bearing applicable to the flywheel energy storage system that consist of HTS-bulks and superconducting-coils

    International Nuclear Information System (INIS)

    Seino, Hiroshi; Nagashima, Ken; Tanaka, Yoshichika; Nakauchi, Masahiko

    2010-01-01

    The Railway Technical Research Institute conducted a study to develop a superconducting magnetic bearing applicable to the flywheel energy-storage system for railways. In the first step of the study, the thrust rolling bearing was selected for application, and adopted liquid-nitrogen-cooled HTS-bulk as a rotor, and adopted superconducting coil as a stator for the superconducting magnetic bearing. Load capacity of superconducting magnetic bearing was verified up to 10 kN in the static load test. After that, rotation test of that approximately 5 kN thrust load added was performed with maximum rotation of 3000rpm. In the results of bearing rotation test, it was confirmed that position in levitation is able to maintain with stability during the rotation. Heat transfer properties by radiation in vacuum and conductivity by tenuous gas were basically studied by experiment by the reason of confirmation of rotor cooling method. The experimental result demonstrates that the optimal gas pressure is able to obtain without generating windage drag. In the second stage of the development, thrust load capacity of the bearing will be improved aiming at the achievement of the energy capacity of a practical scale. In the static load test of the new superconducting magnetic bearing, stable 20kN-levitation force was obtained.

  17. Nonlinear cyclotron absorption and stimulated scattering

    International Nuclear Information System (INIS)

    Chung, T.H.

    1986-01-01

    In electron cyclotron resonance heating (ECRH), wave sources heating a plasma linearly with respect to intensity; but as the intensity of ECRH gets larger, there might appear nonlinear effects that would result in cutoff of net absorption. This thesis uses quantum mechanical theory to derive a threshold microwave intensity for nonlinear absorption. The quantum mechanical theory estimates that the threshold microwave intensity for nonlinear absorption is about 10 5 watts/cm 2 for a microwave heating experiment (T/sub e/ = 100 ev, λ = 3,783 cm, B = 2.5 kG). This value seems large considering the present power capabilities of microwave sources (10 2 ∼ 10 3 watts/cm 2 ), but for a low temperature plasma, this threshold will go down. There is another nonlinear phenomenon called stimulated cyclotron scattering that enhances photon scattering by electrons gyrating in a magnetic field. This is expected to prevent incoming photons from arriving at the central region of the fusion plasma, where absorption mainly takes place. Theory based on a photon transport model predicts that the threshold intensity for the stimulated cyclotron scattering is about 10 4 watts/cm 2 for the plasma parameters mentioned above. This value seems large also, but a longer wavelength of microwaves and a larger magnitude magnetic field, which will be the case in reactor type facilities, will lower the threshold intensity to levels comparable with the currently developed microwave sources

  18. Investigation, modelling and control of the 1.9 K cooling loop for superconducting magnets for the Large Hadron Collider

    CERN Document Server

    Flemsæter, Bjorn

    2000-01-01

    The temperature of the superconducting magnets for the 27 km LHC particle accelerator under construction at CERN is a control parameter with strict operating constraints imposed by (a) the maximum temperature at which the magnets can operate, (b) the cooling capacity of the cryogenic system, (c) the variability of applied heat loads and (d) the accuracy of the instrumentation. A pilot plant for studying aspects beyond single magnet testing has been constructed. This magnet test string is a 35-m full-scale model if the LHC and consists of four superconducting cryogmagnets operating in a static bath of He II at 1.9 K. An experimental investigation of the properties dynamic characteristics of the 1.9 K cooling loop of the magnet test string has been carried out. A first principle model of the system has been created. A series of experiments designed for system identification purposes have been carried out, and black box models of the system have been created on the basis on the recorded data. A Model Predictive ...

  19. All-magnetic extraction for cyclotron beam reacceleration

    Science.gov (United States)

    Hudson, E.D.; Mallory, M.L.

    1975-07-22

    An isochronous cyclotron can be modified to provide an initial electron stripping stage, a complete acceleration of the stripped ions through the cyclotron to a first energy state, means for returning the ions to an intermediate cyclotron orbit through a second stripping stage, further acceleration of the now higher energy stripped ions through the cyclotron to their final energy, and final extraction of the ions from the cyclotron. (auth)

  20. Critical current density improvements in MgB2 superconducting bulk samples by K2CO3 additions  

    DEFF Research Database (Denmark)

    Grivel, J.-C.

    2018-01-01

    MgB2 bulk samples with potassium carbonate doping were made by means of reaction of elemental Mg and B powders mixed with various amounts of K2CO3. The Tc of the superconducting phase as well as its a-axis parameter were decreased as a result of carbon doping. Potassium escaped the samples during...... reaction. The critical current density of MgB2 was improved both in self field and under applied magnetic field for T ≤ 30 K, with optimum results for 1 mol% K2CO3 addition. The normalized flux pinning force (f(b)) shows that the flux pinning mechanism at low field is similar for all samples, following...

  1. Nematicity, magnetism and superconductivity in FeSe.

    Science.gov (United States)

    Böhmer, Anna E; Kreisel, Andreas

    2018-01-17

    Iron-based superconductors are well known for their complex interplay between structure, magnetism and superconductivity. FeSe offers a particularly fascinating example. This material has been intensely discussed because of its extended nematic phase, whose relationship with magnetism is not obvious. Superconductivity in FeSe is highly tunable, with the superconducting transition temperature, T c , ranging from 8 K in bulk single crystals at ambient pressure to almost 40 K under pressure or in intercalated systems, and to even higher temperatures in thin films. In this topical review, we present an overview of nematicity, magnetism and superconductivity, and discuss the interplay of these phases in FeSe. We focus on bulk FeSe and the effects of physical pressure and chemical substitutions as tuning parameters. The experimental results are discussed in the context of the well-studied iron-pnictide superconductors and interpretations from theoretical approaches are presented.

  2. Trends in cyclotrons for radionuclide production

    International Nuclear Information System (INIS)

    Vera Ruiz, H.; Lambrecht, R.M.

    1999-01-01

    The IAEA recently concluded a worldwide survey of the cyclotrons used for radionuclide production. Most of the institutions responded to the questionnaire. The responses identified technical, utilisation and administrative information for 206 cyclotrons. Compiled data includes the characteristics, performance and popularity of each of the different commercial cyclotrons. Over 20 cyclotrons are scheduled for installation in 1998. The expansion in the number of cyclotron installations during the last decade was driven by the advent of advances in medical imaging instrumentation (namely, positron emission tomography (PET), and more recently by 511 KeV emission tomography); introduction of user friendly compact medical cyclotrons; and recent governmental decisions that permit reimbursement for cyclotron radiopharmaceutical studies by the government or insurance companies. The priorities for the production of clinical, commercial and research radionuclides were identified. The emphasis is on radionuclides used for medical diagnosis with SPET (e.g. 123 I, 201 Tl) and PET (e.g. 11 C, 13 N, 15 O, 18 F) radiopharmaceuticals, and for individualized patient radiation treatment planning (e.g. 64 Cu, 86 Y, 124 I) with PET. There is an emerging trend to advance the cyclotron as an alternative method to nuclear reactors for the production of neutron-rich radionuclides (e.g. 64 Cu, 103 Pd, 186 Re) needed for therapeutic applications. (authors)

  3. Exotic Magnetic Orders and Their Interplay with Superconductivity

    DEFF Research Database (Denmark)

    Christensen, Morten Holm

    Superconductivity represents one of the most important scientific discoveries of the 20th century. The practical applications are numerous ranging from clean energy storage and MRI machines to quantum computers. However, the low temperatures required for superconductivity prohibits many practical...... applications. The more recent discovery of high-temperature superconductors, with superconducting transition temperatures above 100~K, has led to the hope that superconductivity at room-temperature might be achievable, although a complete theoretical understanding of the high-temperature superconductors...

  4. Future cyclotron systems : an industrial perspective

    International Nuclear Information System (INIS)

    Stevenson, N.R.; Dickie, W.J.

    1995-09-01

    The use of commercial cyclotron systems for the production of radioisotopes continues to grow on a world-wide scale. Improvements in technology have significantly increased the production capabilities of modem cyclotron-based isotope production facilities. In particular, the change to negative ion acceleration and new high power systems have resulted in dramatic improvements in reliability, increases in capacity, and decreases in personnel radiation dose. As more and more older machines are retired decisions regarding their replacement are made based on several factors including the market's potential and the cyclotron system's abilities. Taking the case of the recently upgraded TR30 cyclotron at TRIUMF/Nordion, we investigate the requirements industrial/medical users are likely to impose on future commercial cyclotron systems and the impact this will have on cyclotron technology by the end of the century. (author)

  5. Future cyclotron systems: An industrial perspective

    International Nuclear Information System (INIS)

    Stevenson, N.R.; Dickie, W.J.

    1995-09-01

    The use of commercial cyclotron systems for the production of radioisotopes continues to grow on a world-wide scale. Improvements in technology have significantly increased the production capabilities of modern cyclotron-based isotope production facilities. In particular, the change to negative ion acceleration and new high power systems have resulted in dramatic improvements in reliability, increases in capacity, and decreases in personnel radiation dose. As more and more older machines are retired, decisions regarding their replacement are made based on several factors including the market's potential and the cyclotron system's abilities. Taking the case of the recently upgraded TR30 cyclotron at TRIUMF/Nordion, the authors investigate the requirements industrial/medical users are likely to impose on future commercial cyclotron systems and the impact this will have on cyclotron technology by the end of the century

  6. Development of superconducting acceleration cavity technology for free electron lasers

    International Nuclear Information System (INIS)

    Lee, Jong Min; Lee, Byung Cheol; Kim, Sun Kook; Jeong, Young Uk; Cho, Sung Oh

    2000-10-01

    As a result of the cooperative research between the KAERI and Peking University, the key technologies of superconducting acceleration cavity and photoelectron gun have been developed for the application to high power free electron lasers. A 1.5-GHz, 1-cell superconducting RF cavity has been designed and fabricated by using pure Nb sheets. The unloaded Q values of the fabricated superconducting cavity has been measured to be 2x10 9 at 2.5K, and 8x10 9 at 1.8K. The maximum acceleration gradient achieved was 12 MeV/m at 2.5K, and 20MV/m at 1.8 K. A cryostat for the 1-cell superconducting cavity has been designed. As a source of electron beam, a DC photocathode electron gun has been designed and fabricated, which is composed of a photocathode evaporation chamber and a 100-keV acceleration chamber. The efficiency of the Cs2Te photocathode is 3% nominally at room temperature, 10% at 290 deg C. The superconducting photoelectron gun system developed has been estimated to be a good source of high-brightness electron beam for high-power free electron lasers

  7. Development of superconducting acceleration cavity technology for free electron lasers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Min; Lee, Byung Cheol; Kim, Sun Kook; Jeong, Young Uk; Cho, Sung Oh

    2000-10-01

    As a result of the cooperative research between the KAERI and Peking University, the key technologies of superconducting acceleration cavity and photoelectron gun have been developed for the application to high power free electron lasers. A 1.5-GHz, 1-cell superconducting RF cavity has been designed and fabricated by using pure Nb sheets. The unloaded Q values of the fabricated superconducting cavity has been measured to be 2x10{sup 9} at 2.5K, and 8x10{sup 9} at 1.8K. The maximum acceleration gradient achieved was 12 MeV/m at 2.5K, and 20MV/m at 1.8 K. A cryostat for the 1-cell superconducting cavity has been designed. As a source of electron beam, a DC photocathode electron gun has been designed and fabricated, which is composed of a photocathode evaporation chamber and a 100-keV acceleration chamber. The efficiency of the Cs2Te photocathode is 3% nominally at room temperature, 10% at 290 deg C. The superconducting photoelectron gun system developed has been estimated to be a good source of high-brightness electron beam for high-power free electron lasers.

  8. Overview of superconductivity in Japan - Strategy road map and R and D status

    International Nuclear Information System (INIS)

    Tsukamoto, O.

    2008-01-01

    Superconducting technology benefits society in broad fields; environment/energy, life science, manufacturing industry and information and communication. Superconducting equipments and devices used in various fields are divided into two categories, electric and electronic applications. Technologies in those applications are progressing remarkably owing to firm and consistent supports by various national projects. The final target of the NEDO R and D project of fundamental technology for superconductivity applications to develop 500 m long coated conductors (CCs) of the critical current 300 A/cm (at 77 K, 0 T) will be fulfilled by the end of JFY 2007 and manufacturing process to produce extremely low-cost CCs is to be developed to make the applications realistic. Preliminary works to develop power apparatuses using CCs have started in the frame of the R and D project for the fundamental technology and have produced significant results. Performance of BSCCO/Ag-sheathed wires has been improved greatly and various applications using those wires are being developed. R and D projects for SMES, power cable, flywheel energy storage and rotating machines are going to introduce those equipments to the real world. Technologies of SQUID and SFQ, basic devices of the electronic applications, are progressing dramatically also owing to various national projects. In this back ground the technology strategy map in the field of superconducting technology was formulated to prioritize investments in R and D by clearly defining the objectives and inspire autonomous R and D actives in various fields of industries. R and D activities in the superconducting technologies are to be scheduled following this strategy map

  9. Low-temperature synthesis of superconducting nanocrystalline MgB2

    International Nuclear Information System (INIS)

    Lu, J.; Xiao, Z.; Lin, Q.; Claus, H.; Fang, Z.Z.

    2010-01-01

    Magnesium diboride (MgB 2 ) is considered a promising material for practical application in superconducting devices, with a transition temperature near 40 K. In the present paper, nanocrystalline MgB 2 with an average particle size of approximately 70 nm is synthesized by reacting LiBH 4 with MgH 2 at temperatures as low as 450 C. This synthesis approach successfully bypasses the usage of either elemental boron or toxic diborane gas. The superconductivity of the nanostructures is confirmed by magnetization measurements, showing a superconducting critical temperature of 38.7 K.

  10. Magneto-optical and cyclotron resonance studies of semiconductors and their nanostructures in pulsed high magnetic fields

    International Nuclear Information System (INIS)

    Miura, N.

    1999-01-01

    Full text: We present a review on the recent advances in physics of magneto-optical spectroscopy in the visible range and of infrared cyclotron resonance in pulsed high magnetic fields, which are produced by electromagnetic flux compression up to 500T, by the single-turn coil technique up to 200T or by conventional non-destructive long pulse magnets up to 50T. We discuss the recent results on the spectroscopy of low dimensional excitons in quantum wells and short period superlattices. In very high fields up to 500T, we observed anomalous field dependence of the exciton absorption lines and the 2D - 3D cross-over effects in GaAs/AlAs quantum wells. In GaP/AlP short period superlattices, it was found that the exciton photoluminescence intensity shows a dramatic decrease and the diamagnetic shift was negative when high magnetic fields were applied parallel to the growth direction. We observed also remarkable effects of uniaxial stress, which are ascribed to the cross-over effect between the two inequivalent valleys at the X points. Cyclotron resonance was measured by using various molecular gas lasers as radiation sources in the range 5 - 119 m . We present the results of cyclotron resonance in GaAs/AlGaAs quantum wells with tilted magnetic fields from the growth direction. It was found that the resonant field and the peak intensity show many different features depending on the extent of the Landau level-subband coupling and on the relation between the photon energy and the barrier height. A large hysteresis was observed between the rising and the falling sweeps of the magnetic field, when the cyclotron resonance energy became comparable with the subband spacing. In a diluted magnetic semiconductor CdFeS, we observed anomalous temperature dependence of the effective mass, suggestive of the magnetic polaron effect

  11. Cryocooler-cooled 10 T superconducting magnet; Reitoki chokurei hoshiki no 10T chodendo jishaku

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, T.; Yamamoto, K.; Urata, M. [Toshiba Corp., Tokyo (Japan)

    1995-09-01

    A superconducting magnet totally free of such cooling agents as liquefied helium has been developed, which can be cooled by a cryocooler alone in a direct cooler cooled method, and a success was attained when a 10T magnetic field was generated in a vacancy 10cm in diameter. The value is the highest in the world realized by a system not using a cooling medium (only 7.7T attained before this). The coil comprises a coil of an NbTi superconducting lead and a coil of Nb3Sn superconducting lead, and is impregnated with epoxy resin for reduction in size. It is cooled only by heat conduction thanks to a thermally coupled 4K cooler in vacuum, and necessitates the insertion of indium between the coil and a copper made cooling board which combination is further tightened up by a stainless steel wire. Furthermore, a superconducting oxide lead has been developed, with its performance not lowered even in an intensive magnetic field, for the supply of power to the coil, and this suppresses the infiltration of conduction caused heat and the generation of Joule heat. The magnet is designed small and light with dimensions 650{times}500{times}490mm (height), and can be operated by mere manipulation of a switch. 6 refs., 6 figs.

  12. Design and development progress of a LLRF control system for a 500 MHz superconducting cavity

    Science.gov (United States)

    Lee, Y. S.; Kim, H. W.; Song, H. S.; Lee, J. H.; Park, K. H.; Yu, I. H.; Chai, J. S.

    2012-07-01

    The LLRF (low-level radio-frequency) control system which regulates the amplitude and the phase of the accelerating voltage inside a RF cavity is essential to ensure the stable operation of charged particle accelerators. Recent advances in digital signal processors and data acquisition systems have allowed the LLRF control system to be implemented in digitally and have made it possible to meet the higher demands associated with the performance of LLRF control systems, such as stability, accuracy, etc. For this reason, many accelerator laboratories have completed or are completing the developments of digital LLRF control systems. The digital LLRF control system has advantages related with flexibility and fast reconfiguration. This paper describes the design of the FPGA (field programmable gate array) based LLRF control system and the status of development for this system. The proposed LLRF control system includes an analog front-end, a digital board (ADC (analog to digital converter), DAC (digital to analog converter), FPGA, etc.) and a RF & clock generation system. The control algorithms will be implemented by using the VHDL (VHSIC (very high speed integrated circuits) hardware description language), and the EPICS (experiment physics and industrial control system) will be ported to the host computer for the communication. In addition, the purpose of this system is to control a 500 MHz RF cavity, so the system will be applied to the superconducting cavity to be installed in the PLS storage ring, and its performance will be tested.

  13. Superconductivity and Competing Ordered Phase in RuPn (Pn = As, P)

    Science.gov (United States)

    Hirai, Daigorou; Takayama, Tomohiro; Hashizume, Daisuke; Yamamoto, Ayako; Takagi, Hidenori

    2011-03-01

    Unconventional superconductivity likely manifests itself when some competing electronic phases are suppressed down to zero temperature such as cuprates and iron-pnictide superconductors. Therefore, the correlated metallic state neighboring a competing electronic ordering can be a promising playground for unconventional superconductivity. Here we report superconductivity emerging adjacent to electronically ordered phases of RuPn (Pn = As, P). We found that RuAs(P) exhibits phase transitions at 240 (265) K, which is discerned as a drop of magnetic susceptibility or a resistivity upturn. Such anomalies can be suppressed by substituting Rh to the Ru site. Accompanied by the disappearance of the electronic order, superconductivity was found to emerge below 1.8 K and 3.8 K for RuAs and RuP, respectively. The superconductivity in Rh substituted RuPn, which neighbors a competing electronic order, might exhibit an exotic pairing state as seen in the unconventional superconductors known to date.

  14. Solid targets and irradiation facilities for production of diagnostic and therapeutic radionuclides at the Debrecen cyclotron

    International Nuclear Information System (INIS)

    Tarkanyi, F.; Ando, L.; Szucs, Z.; Mahunka, I.; Kovacs, Z.

    2000-01-01

    The MGC-20E (NIIEFA, Leningrad, USSR) variable energy compact cyclotron (k=20) was installed in ATOMKI (Debrecen, Hungary) in 1985. Protons, deuterons, 3 He- and α-particles can be accelerated with currents up to 300 μA for internal irradiation and up to 50 μA for external beams. The establishment of the Cyclotron Laboratory was partly supported by the International Atomic Energy Agency. The application of the cyclotron is multipurpose: basic nuclear research, application of activation technique for analytical and wear studies, application of intense fast neutron source for agro-biological, bio-medical application and for radiation damage test of electronic components, and finally radioisotope production for medical diagnostics and for other scientific and applied fields. The cyclotron laboratory has six target rooms, a radiochemistry laboratory and a medical unit equipped with PET

  15. Superconducting cavities for HERA

    International Nuclear Information System (INIS)

    Dwersteg, B.; Ebeling, W.; Moeller, W.D.; Renken, D.; Proch, D.; Sekutowicz, J.; Susta, J.; Tong, D.

    1988-01-01

    Superconducting 500 MHz cavities are developed to demonstrate the feasibility of upgrading the e-beam energy of the HERA storage ring. A prototype module with 2 x 4 cell resonators and appropriate fundamental and higher mode couplers has been designed at DESY and is being built by industrial firms. The design and results of RF and cryogenic measurements are reported in detail. 17 references, 10 figures, 2 tables

  16. Operation of a quasioptical electron cyclotron maser

    International Nuclear Information System (INIS)

    Morse, E.C.; Pyle, R.V.

    1984-12-01

    The electron cyclotron maser or gyrotron concept has been developed to produce sources producing 200 kW at 28 GHz continuously, and higher power outputs and frequencies in pulsed mode. These sources have been useful in electron cyclotron resonance heating (ECRH) in magnetically confined fusion devices. However, higher frequencies and higher power levels will be required in reactor-grade fusion plasmas, with likely requirements of 1.0 MW or more per source at 140 GHz. Conventional gyrotrons follow a trend of decreasing power for increasing frequency. In order to circumvent this problem, the quasioptical electron cyclotron maser was proposed. In this device, the closed resonator of the conventional gyrotron is replaced with an open, Fabry-Perot type resonator. The cavity modes are then the TEM-type modes of an optical laser. The advantage of this configuration is that the cavity size is not a function of frequency, since the length can be any half-integer number of wavelengths. Furthermore, the beam traverses across the cavity transverse to the direction of radiation output, and thus the rf window design is less complicated than in conventional tubes. The rf output, if obtained by diffraction coupling around one of the mirrors, could be in a TEM mode, which would allow for quasioptical transmission of the microwaves into the plasma in fusion devices. 4 references, 1 figure

  17. Visual assistance system for cyclotron operation

    International Nuclear Information System (INIS)

    Okamura, Tetsuya; Tachikawa, Toshiki; Murakami, Tohru.

    1994-01-01

    A computer-based operation system for a cyclotron which assists operators has been developed. It is the operation assistance system depending on visual sense to indicate beam parameters to operators. First, the mental model of operators at the time of beam adjustment was analyzed, and it was presumed to be composed of five partial mental models, that is, beam behavior model, feasible setting region model, parameter sensitivity model, parameter interrelation model and status map model. Next, three visual interfaces were developed. Beam trajectory is rapidly calculated and graphically displayed whenever operators change parameters. Feasible setting regions (FSR) for parameters that satisfy the beam acceptance criteria of a cyclotron are indicated. The distribution of beam current values which are the quantity for evaluating adjustment is indicated as search history. Finally, for evaluating the system effectiveness, the search time required to reach the optimum conditions was measured. In addition, the system usability was evaluated by written questionnaires. The result of experiment showed the reduction of search time by about 65%. The written questionnaires survey showed the operators highly evaluate system usability. (K.I.)

  18. MMS Observations of Harmonic Electromagnetic Cyclotron Waves

    Science.gov (United States)

    Usanova, M.; Ahmadi, N.; Ergun, R.; Trattner, K. J.; Fuselier, S. A.; Torbert, R. B.; Mauk, B.; Le Contel, O.; Giles, B. L.; Russell, C. T.; Burch, J.; Strangeway, R. J.

    2017-12-01

    Harmonically related electromagnetic ion cyclotron waves with the fundamental frequency near the O+ cyclotron frequency were observed by the four MMS spacecraft on May 20, 2016. The wave activity was detected by the spacecraft on their inbound passage through the Earth's morning magnetosphere during generally quiet geomagnetic conditions but enhanced solar wind dynamic pressure. It was also associated with an enhancement of energetic H+ and O+ ions. The waves are seen in both magnetic and electric fields, formed by over ten higher order harmonics, most pronounced in the electric field. The wave activity lasted for about an hour with some wave packets giving rise to short-lived structures extending from Hz to kHz range. These observations are particularly interesting since they suggest cross-frequency coupling between the lower and higher frequency modes. Further work will focus on examining the nature and role of these waves in the energetic particle dynamics from a theoretical perspective.

  19. Contribution to the study of superconducting magnets using high transition temperature superconducting materials

    International Nuclear Information System (INIS)

    Lecrevisse, Thibault

    2012-01-01

    The new industrial superconductors using high critical temperature compounds offer new possibilities for superconducting magnetism. Indeed they allow higher magnetic field with the same classical cryogenics at 4.2 K on one hand, and on the other hand they also pave the way for superconducting magnets working between 10 K and 30 K. The high temperature superconductors are then needed in order to produce magnetic fields higher than 16 T (case of HTS dipole insert for Large Hadron Collider at CERN) or to increase the specific density stored in one SMES (Superconducting Magnetic Energy Storage, in the case of the SuperSMES ANR Project).Nevertheless the indisputable assets (critical temperature, critical magnetic field, mechanical stresses) brought by the use of High critical temperature superconductors like YBCO, used in superconducting magnets, require to solve some challenges. Their behavior is still badly understood, especially during the resistive transitions. To succeed in protecting these conductors we need a new reflection on protection schemes designed to avoid the thermal and mechanical damages. The answer to the question: 'Can we use those materials in the long run inside superconducting magnets?' is now inescapable.Some answers are given here. The use of the conductors is approached through various experimental studies to understand the material (electrical characterization and modeling of the critical surface) and to define the key stages of high critical temperature superconducting magnets manufacturing (work on the junctions between conductors and pancakes). This study led to the creation of two coils in order to identify the issues related to the use of YBCO tapes. A numerical thermo-electrical model of the high critical temperature superconductor has been developed and a numerical code based on the CEA software CASTEM (Finish Elements Model) allowed to study the resistive transition (or quench) behavior of those conductor and coil. The code has been

  20. Development of superconducting magnets for RAON 28 GHz ECR ion source.

    Science.gov (United States)

    Heo, Jeongil; Choi, Sukjin; Kim, Yonghwan; Hong, In-Seok

    2016-02-01

    RAON, a 28 GHz electron cyclotron resonance ion source (ECR IS), was designed and tested as a Rare Isotope Science Project. It is expected that RAON would provide not only rare-isotope beams but also stable heavy ions ranging from protons to uranium. In order to obtain the steady heavy-ion beam required for ECR IS, we must use a 28 GHz microwave source as well as a high magnetic field. A superconducting magnet using a NbTi wire was designed and manufactured for producing the ECR IS and a test was conducted. In this paper, the design and fabrication of the superconducting magnet for the ECR IS are presented. Experimental results show that the quench current increases whenever quenching occurs, but it has not yet reached the designed current. The experiment is expected to reveal the ideal conditions required to reach the designed current.

  1. Computer design of a compact cyclotron

    International Nuclear Information System (INIS)

    Bing Wang; Huanfeng Hao; Qinggao Yao; Jinquan Zhang; Mingtao Song; Vorozhtsov, S.B.; Smirnov, V.L.; Hongwei Zhao

    2011-01-01

    Here we present results of the computer design of the structural elements of a compact cyclotron by the example of HITFiL cyclotron selected as the driving accelerator that is under construction at the Institute of Modern Physics (Lanzhou, China). In the article a complex approach to modeling of the compact cyclotron, including calculation of electromagnetic fields of the structural elements and beam dynamics calculations, is described. The existing design data on the axial injection, magnetic, acceleration and extraction systems of the cyclotron are used as a starting point in the simulation. Some of the upgrades of the cyclotron structural elements were proposed, which led to substantial improvement of the beam quality and transmission

  2. Bi-based superconducting fibers with high critical parameters

    International Nuclear Information System (INIS)

    Huo Yujing; He Yusheng; Liu Menglin; Mao Sining; Cai Liying; Wang Ying; Zhang Jincang; He Aisheng; Wang Jinsong

    1991-01-01

    Superconducting fibers of Bi(Pb)-Sr-Ca-Cu-O high Tc superconducting materials have been prepared by means of the laser-heated pedestal growth (LHPG) method. The highest zero resistance temperature T c0 reaches is 114K, and the highest critical current density J c (77K, O T) is greater than 5000 A/cm 2 . As-grown superconducting fibers were successfully fabricated without post growth heat treatment. Amorphous materials were used for the first time to make high quality fibers. The influence of growth conditions, thermal treatment and the composition of the fibers were discussed. (author). 5 refs., 7 figs., 3 tabs

  3. Development of Nb-Ti multifilamentar superconducting wires

    International Nuclear Information System (INIS)

    Otubo, J.

    1986-01-01

    Ni-Ti superconducting wires with multifilamentar configuration were produced, using the grouping technique. Some basic concepts on superconductivity and its main critical parameters are presented. The criteria for stabilizing superconductors in terms of the geometry are studied. The main critical parameters, H c , J c , T c in function of the composition and the metallurgical structure of Ni-Ti alloy are analysed. The development of Ni-Ti superconducting wires is described. (M.C.K.) [pt

  4. Research on the Best Root Span of 500kV Substation Frame Based on Finite Element

    Science.gov (United States)

    Chen, Hao; Fang, Qing; Chen, Haoyuan

    2018-01-01

    A-shaped and steel tube structures have been widely applied when designing 500kV substation frame in China. While, compared with steel tube, angle steels have an advantage of easy-transporting, especially in oversea projects. However, researches on substation frame with angle steel were not enough. In order to find out the best root span of 500kV substation frame under similar engineering conditions, using the overseas project substation frame as an example, the substation frames with different root span have been detailed calculated, to find the best root span according to the cost of it. When the height of column is about 30m, the root suggestion value is 6.1m×3.1m. And then, the buckling analysis of the overall structure has been carried out by ANSYS, to find out that the weak part of the structure is in the middle of it. The structural adjustment is carried out for the weak part, including adjusting the web members and the chord members, to obtain a higher bearing capacity of the structure.

  5. Startup work on Inshas cyclotron

    International Nuclear Information System (INIS)

    Vorogushin, M.F.; Strokach, A.P.; Shikhov, V.Ya.; Galchuk, A.V.; Soliman, A.N.; El-Abyad, M.; Comsan, M.N.H.; Saleh, Z.A.; Azzam, A.N.

    2001-01-01

    Startup works on the MGC-20 variable energy cyclotron in the Inshas Nuclear Research Center (Egypt) are described. The cyclotron is intended for acceleration of hydrogen and helium ions in a wide energy range (for protons - from 5 to 20 MeV). Main units of the cyclotron and results of computer experimental acceleration of protons to 18 MeV are described. The prospects of furthers investigations are presented [ru

  6. Superconductivity in Weyl semimetal candidate MoTe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Yanpeng; Naumov, Pavel; Rajamathi, Catherine; Barkalov, Oleg; Wu, Shu-Chun; Shekhar, Chandra; Sun, Yan; Suess, Vicky; Schmidt, Marcus; Schwarz, Ulrich; Schnelle, Walter; Felser, Claudia; Medvedev, Sergey [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Ali, Mazhar; Cava, Robert [Department of Chemistry, Princeton University, Princeton (United States); Hanfland, Michael [European Synchrotron Radiation Facility, Grenoble (France); Pippel, Eckhard; Werner, Peter; Hillebrand, Reinald; Parkin, Stuart [Max Planck Institute of Microstructure Physics, Halle (Germany); Foerster, Tobias; Kampert, Erik [Dresden High Magnetic Field Laboratory, Dresden (Germany); Yan, Binghai [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for the Physics of Complex Systems, Dresden (Germany)

    2016-07-01

    In this work, we investigate the sister compound of WTe{sub 2}, MoTe{sub 2}, which is also predicted to be a Weyl semimetal and a quantum spin Hall insulator in bulk and monolayer form, respectively. We find that MoTe{sub 2} exhibits superconductivity with a resistive transition temperature T{sub c} of 0.1 K. The application of a small pressure is shown to dramatically enhance the T{sub c}, with a maximum value of 8.2 K being obtained at 11.7 GPa (a more than 80-fold increase in Tc). This yields a dome-shaped superconducting phase diagram. Further explorations into the nature of the superconductivity in this system may provide insights into the interplay between superconductivity and topological physics.

  7. Kramers non-magnetic superconductivity in LnNiAsO superconductors.

    Science.gov (United States)

    Li, Yuke; Luo, Yongkang; Li, Lin; Chen, Bin; Xu, Xiaofeng; Dai, Jianhui; Yang, Xiaojun; Zhang, Li; Cao, Guanghan; Xu, Zhu-an

    2014-10-22

    We investigated a series of nickel-based oxyarsenides LnNiAsO (Ln=La, Ce, Pr, Nd, Sm) compounds. CeNiAsO undergoes two successive anti-ferromagnetic transitions at TN1=9.3 K and TN2=7.3 K; SmNiAsO becomes an anti-ferromagnet below TN≃3.5 K; NdNiAsO keeps paramagnetic down to 2 K but orders anti-ferromagnetically below TN≃1.3 K. Superconductivity was observed only in Kramers non-magnetic LaNiAsO and PrNiAsO with Tc=2.7 K and 0.93 K, respectively. The superconductivity of PrNiAsO is further studied by upper critical field and specific heat measurements, which reveal that PrNiAsO is a weakly coupled Kramers non-magnetic superconductor. Our work confirms that the nickel-based oxyarsenide superconductors are substantially different in mechanism to iron-based ones, and are likely to be described by the conventional superconductivity theory.

  8. Cyclotron Production of Technetium-99m

    Science.gov (United States)

    Gagnon, Katherine M.

    Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

  9. A study on the development of high Tc superconducting materials

    International Nuclear Information System (INIS)

    Won, Dong Yeon; Lee, Hee Gyoun; Kim, Chan Joong

    1990-01-01

    The microstructure, crystal structure and formation kinetics for the superconducting phases were studied in the lead-doped BiSrCaCuO system. The formation kinetics was also investigated in the samples with different Pb/Bi ratio and it was observed that the 30 % Pb addition is most perferable for the formation of the high T c phase. The formation of the high T c phase was delayed by the excessive addition of Pb. The lattice parameter (c) of the unit cell of both low T c and high T c phases increased with increasing Pb content. Superconducting thin film was sucessfully prepared by chemical vapor deposition (CVD). Film deposited on MgO substrate showed a T c , onset of 85 K and did not reach to zero resistivity down to 77 K. Superconducting 124 phase in Y-system, which is more stable than 123 phase at high temperature showed a T c , onser of 84 K. Additionally, 0.1 mole of Pb, Sn and Ca was substituted for yttrium in 124 phase, respectively. For Pb and Sn-subsituted specimens, 124 phase was formed and for Ca substituted specimen, 124 phase was not formed and revealed no superconductivity down to 77 K. For Sn-substituted specimens, 124 phase was formed but showed no superconductivity down to 77 K. (author)

  10. Superconducting magnet for a Ku-band maser.

    Science.gov (United States)

    Berwin, R.; Wiebe, E.; Dachel, P.

    1972-01-01

    A superconducting magnet to provide a uniform magnetic field of up to 8000 G in a 1.14-cm gap for the 15.3-GHz (Ku-band) traveling wave maser is described. The magnet operates in a persistent mode in the vacuum environment of a closed-cycle helium refrigerator (4.5 K). The features of a superconducting switch, which has both leads connected to 4.5 K heat stations and thereby does not receive heat generated by the magnet charging leads, are described.

  11. The capacitor banks for the text diagnostic neutral beam and electron cyclotron heating experiments

    International Nuclear Information System (INIS)

    Nelin, K.; Jagger, J.; Baker, M.; Ourou, A.; De Turk, P.

    1986-01-01

    The Texas Experimental Tokamak (TEXT) has been operational since November of 1980. Since that time, many experimental systems have been added to the machine. Currently, two major experiments are being added to compliment the diagnostics already online. These systems, the Diagnostic Neutral Beam (DNB) and the Electron Cyclotron Heating (ECH) experiments are described in separate papers. A set of five modular, bipolar capacitor banks are used to power both the DNB and the ECH. The total capacitance of the banks is 92μF. The stored energy is about 500kJ at+or-100kV. The banks are built as five identical, interchangeable modules. One module is adequate to run the DNB. Up to four banks are used to power the ECH. The banks are portable so that they can be moved to the open end of the laboratory for maintenance. This gives much better access for repair work and allows the experiments to continue to run with the remaining banks. Due to budgetary constraints, these banks were constructed in the most economical manner possible consistent with worker safety and long term reliability. The capacitors themselves are on loan from Los Alamos National Labs. They are rated at 1.85μF at 60kV. Our application requires that they be used in a series/parallel configuration with a peak voltage of 50kV each. This paper describes the electrical, mechanical and control design considerations required to achieve a working set of banks

  12. Superconductivity in gallium-substituted Ba8Si46 clathrates

    Science.gov (United States)

    Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

    2007-02-01

    We report a joint experimental and theoretical investigation of superconductivity in Ga-substituted type-I silicon clathrates. We prepared samples of the general formula Ba8Si46-xGax , with different values of x . We show that Ba8Si40Ga6 is a bulk superconductor, with an onset at TC≈3.3K . For x=10 and higher, no superconductivity was observed down to T=1.8K . This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with TC≈8K . Suppression of superconductivity can be attributed primarily to a decrease in the density of states at the Fermi level, caused by a reduced integrity of the sp3 -hybridized networks as well as the lowering of carrier concentration. These results are corroborated by first-principles calculations, which show that Ga substitution results in a large decrease of the electronic density of states at the Fermi level, which explains the decreased superconducting critical temperature within the BCS framework. To further characterize the superconducting state, we carried out magnetic measurements showing Ba8Si40Ga6 to be a type-II superconductor. The critical magnetic fields were measured to be HC1≈35Oe and HC2≈8.5kOe . We deduce the London penetration depth λ≈3700Å and the coherence length ξc≈200Å . Our estimate of the electron-phonon coupling reveals that Ba8Si40Ga6 is a moderate phonon-mediated BCS superconductor.

  13. Synchrotron radiation and absorption at electron cyclotron harmonics in inhomogeneous plasmas

    International Nuclear Information System (INIS)

    Hu, Jian-Long.

    1993-01-01

    In order to understand fully the absorption, emission and conversion phenomena for any electron cyclotron harmonic, one must include all relevant mode conversion processes and a finite parallel wave number k parallel . Relativistic plasma mode conversion and tunneling equations at the second and third electron cyclotron harmonics have been derived analytically. A finite k parallel has been introduced which keeps the coupling between the O-mode, the X-mode and the Bernstein wave in the mode conversion problems without absorption have been obtained, and the connection formulas between different wave branches have been established. The corresponding transmission, reflection and conversion coefficients have also been given. Mode conversion problem at any harmonic has been generalized to either a three branch or a five branch problem. A comparison between the coupled equation and the uncoupled equation has been made. The effort has been directed at the third harmonic since the adsorption at ω = 2ω ce is known to be very strong in virtually every fusion case. Both the low density limit and the high density limit cases have been studied separately. The relativistic effects on the mode conversion and absorption problem has been analyzed. The mode conversion equation with absorption has been solved by using the Green function method. The electron cyclotron emission experiments have already begun at 3ω ce , and the third harmonic is the first nontrivial case of importance

  14. Experimental Observation of Non-'S-Wave' Superconducting Behavior in Bulk Superconducting Tunneling Junctions of Yba2Cu3O7-δ

    Directory of Open Access Journals (Sweden)

    Leandro Jose Guerra

    1998-06-01

    Full Text Available Evidence of non-s-wave superconductivity from normal tunneling experiments in bulk tunneling junctions of YBa2Cu3O7-δ is presented. The I-V and dI/dV characteristics of bulk superconducting tunneling junctions of YBa2Cu3O7-δ have been measured at 77.0K and clear deviation from s-wave superconducting behavior has been observed. The result agrees with d-wave symmetry, and interpreting the data in this way, the magnitude of the superconducting energy gap, 2Δ, is found to be (0.038 ± 0.002 eV. Comparing this energy gap with Tc (2Δ/kB Tc = 5.735, indicates that these high-Tc superconductors are strongly correlated materials, which in contrast with BCS-superconductors are believed to be weakly correlated.

  15. Low-velocity superconducting accelerating structures

    International Nuclear Information System (INIS)

    Delayen, J.R.

    1990-01-01

    The present paper reviews the status of RF superconductivity as applied to low-velocity accelerating properties. Heavy-ion accelerators must accelerate efficiently particles which travel at a velocity much smaller than that of light particles, whose velocity changes along accelerator, and also different particles which have different velocity profiles. Heavy-ion superconducting accelerators operate at frequencies which are lower than high-energy superconducting accelerators. The present paper first discusses the basic features of heavy-ion superconducting structures and linacs. Design choices are then addressed focusing on structure geometry, materials, frequency, phase control, and focusing. The report also gives an outline of the status of superconducting booster projects currently under way at the Argonne National Laboratory, SUNY Stony Brook, Weizmann Institute, University of Washington, Florida State, Saclay, Kansas State, Daresbury, Japanese Atomic Energy Research Institute, Legnaro, Bombay, Sao Paulo, ANU (Canberra), and Munich. Recent developments and future prospects are also described. (N.K.) 68 refs

  16. Superconducting linac booster

    International Nuclear Information System (INIS)

    Srinivasan, B.; Betigeri, M.G.; Pandey, M.K.; Pillay, R.G.; Kurup, M.B.

    1997-01-01

    The report on superconducting LINAC booster, which is a joint project of Bhabha Atomic Research Centre (BARC) and Tata Institute of Fundamental Research (TIFR), brings out the work accomplished so far towards the development of the technology of superconducting LINAC to boost the energy of ions from the 14UD Pelletron. The LINAC is modular in construction with each module comprising of a helium cryostat housing four lead-plated quarter wave resonators. The resonators are superconducting for temperatures below 7.19K. An energy boost of 2 MeV/q per module is expected to be achieved. The first module and the post-tandem superbuncher have been fabricated and tested on the LINAC beam line. This report gives a summary of the technological achievements and also brings out the difficulties encountered during the R and D phase. (author)

  17. Superconductivity and structure of gallium under nanoconfinement

    Energy Technology Data Exchange (ETDEWEB)

    Charnaya, E V; Tien, Cheng; Lee, Min Kai [Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan (China); Kumzerov, Yu A [A F Ioffe Physico-Technical Institute RAS, St Petersburg, 194021 (Russian Federation)

    2009-11-11

    Superconductivity and crystalline structure were studied for two nanocomposites consisting of gallium loaded porous glasses with different pore sizes. The superconducting transition temperatures were found to differ from those in known bulk gallium modifications. The transition temperatures 7.1 and 6.7 K were ascribed to two new confined gallium structures, iota- and kappa-Ga, observed by synchrotron radiation x-ray powder diffraction. The evolution of superconductivity on decreasing the pore filling with gallium was also studied.

  18. An internal superconducting ''holding-coil'' for frozen spin targets

    International Nuclear Information System (INIS)

    Dutz, H.; Gehring, R.; Goertz, S.; Kraemer, D.; Meyer, W.; Reicherz, G.; Thomas, A.

    1995-01-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 μm. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  19. An internal superconducting ``holding-coil`` for frozen spin targets

    Energy Technology Data Exchange (ETDEWEB)

    Dutz, H. [Bonn Univ. (Germany). Physikalisches Inst.; Gehring, R. [Bonn Univ. (Germany). Physikalisches Inst.; Goertz, S. [Bonn Univ. (Germany). Physikalisches Inst.; Kraemer, D. [Bonn Univ. (Germany). Physikalisches Inst.; Meyer, W. [Bonn Univ. (Germany). Physikalisches Inst.; Reicherz, G. [Bonn Univ. (Germany). Physikalisches Inst.; Thomas, A. [Bonn Univ. (Germany). Physikalisches Inst.

    1995-03-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 {mu}m. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  20. Superconducting RF activities at Cornell University

    International Nuclear Information System (INIS)

    Kirchgessner, J.; Moffat, D.; Padamsee, H.; Rubin, D.; Sears, J.; Shu, Q.S.

    1990-01-01

    This paper outlines the RF superconductivity research and development work that has taken place at Cornell Laboratory of Nuclear Studies over the past years. The work that has been performed since the last RF superconductivity workshop is emphasized together with a discussion of the direction of future efforts. Past work is summarized first, focusing on research and development activities in the area of RF superconductivity. Superconducting TeV linear collider is then discussed focusing on the application of superconducting RF to a future TeV linear collider. Linear collider structure development is then described centering on the development of a simpler (thereby cheaper) structure for a TeV linear collider. B-factory with superconducting RF is outlined focusing on the formulation of a conceptual design for a B-factory. B-factory structure development is discussed in relation to the advancement in the capability of SC cavities to carry beam currents of several amperes necessary for a high luminosity storage ring. High gradients are discussed as the key to the realization of a high energy superconducting linac or a superconducting RF B-factory. (N.K.)

  1. A superconducting direct-current limiter with a power of up to 8 MVA

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, L. M.; Alferov, D. F., E-mail: DFAlferov@niitfa.ru; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V. [National Technical Physics and Automation Research Institute (Russian Federation)

    2016-12-15

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with a nominal voltage of 3.5 kV and a nominal current of 2 kA was developed, produced, and tested. The SFCL has two main units—an assembly of superconducting modules and a high-speed vacuum circuit breaker. The assembly of superconducting modules consists of nine (3 × 3) parallel–series connected modules. Each module contains four parallel-connected 2G high-temperature superconducting (HTS) tapes. The results of SFCL tests in the short-circuit emulation mode with a maximum current rise rate of 1300 A/ms are presented. The SFCL is capable of limiting the current at a level of 7 kA and break it 8 ms after the current-limiting mode begins. The average temperature of HTS tapes during the current-limiting mode increases to 210 K. After the current is interrupted, the superconductivity recovery time does not exceed 1 s.

  2. A superconducting direct-current limiter with a power of up to 8 MVA

    Science.gov (United States)

    Fisher, L. M.; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V.

    2016-12-01

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with a nominal voltage of 3.5 kV and a nominal current of 2 kA was developed, produced, and tested. The SFCL has two main units—an assembly of superconducting modules and a high-speed vacuum circuit breaker. The assembly of superconducting modules consists of nine (3 × 3) parallel-series connected modules. Each module contains four parallel-connected 2G high-temperature superconducting (HTS) tapes. The results of SFCL tests in the short-circuit emulation mode with a maximum current rise rate of 1300 A/ms are presented. The SFCL is capable of limiting the current at a level of 7 kA and break it 8 ms after the current-limiting mode begins. The average temperature of HTS tapes during the current-limiting mode increases to 210 K. After the current is interrupted, the superconductivity recovery time does not exceed 1 s.

  3. Assessment of the impact of HTSCs on superconducting fault-current limiters

    International Nuclear Information System (INIS)

    Giese, R.F.; Runde, M.

    1992-01-01

    The possible impact of nitrogen-cooled superconductors on the design and cost of superconducting fault-current limiters is assessed by considering the technical specifications such devices must meet and by comparing material properties of 77-K and 4-K superconductors. The main advantage of operating superconducting at 77 K is that the refrigeration operating cost is reduced by a factor of up to 25, and the refrigeration capital cost is reduced by a factor of up to 10. The heat capacity at 77 K is several orders of magnitude larger than at 4 K. This phenomenon increases conductor stability against flux jumps but makes switching from the superconducting to normal state slow and difficult. Therefore, a high critical current density, probably at least 10 5 A/cm 2 , is required

  4. Fabrication of superconducting wire using organometallic precursors and infiltration

    International Nuclear Information System (INIS)

    Lee, Y.J.

    1991-01-01

    Organometallic precursors from naphthenic acid and metal nitrates were used for the synthesis of YBCO oxide superconducting compounds. The characteristics of metal naphthenates as organometallic precursors were investigated by IR spectra, viscosity measurements, and infiltration. 123 superconducting compound obtained from 123 naphthenate showed a Tc of 90 degree K and a rather dense and elongated microstructure. Also, the melting behavior of Ba-cuprates which were used for 123 making was studied. A low-temperature melting process was developed to fabricate silver-sheathed superconducting wire with the powder-in-tube method; flowing argon gas is introduced to the system at 930-945 degree C to reduce the melting temperature of the 123 compound without silver sheath melting. It resulted in a 90 degree K Tc superconducting core with dense and locally aligned microstructure. SEM-EDS and XRD analysis, 4-probe resistance and Jc measurements, and carbon-content determinations were carried out to characterize the microstructure, grain alignment, and superconducting properties of the samples

  5. High-Density Superconducting Cables for Advanced ACTPol

    Science.gov (United States)

    Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.; hide

    2016-01-01

    Advanced ACTPol (AdvACT) is an upcoming Atacama Cosmology Telescope (ACT) receiver upgrade, scheduled to deploy in 2016, that will allow measure- ment of the cosmic microwave background polarization and temperature to the highest precision yet with ACT. The AdvACT increase in sensitivity is partly provided by an increase in the number of transition-edge sensors (TESes) per array by up to a factor of two over the current ACTPol receiver detector arrays. The high-density AdvACT TES arrays require 70 µ m pitch superconducting flexible cables (flex) to connect the detec- tor wafer to the first-stage readout electronics. Here, we present the flex fabrication process and test results. For the flex wiring layer, we use a 400-nm-thick sputtered alu- minum film. In the center of the cable, the wiring is supported by a polyimide substrate, which smoothly transitions to a bare (uncoated with polyimide) silicon substrate at the ends of the cable for a robust wedge wire-bonding interface. Tests on the first batch of flex made for the first AdvACT array show that the flex will meet the requirements for AdvACT, with a superconducting critical current above 1 mA at 500 mK, resilience to mechanical and cryogenic stress, and a room temperature yield of 97%.

  6. Thermal expansion of superconducting fulleride and borocarbide compounds

    International Nuclear Information System (INIS)

    Burkhart, G.J.

    1995-08-01

    In order to detact and analyze thermodynamic phase transitions, the investigation of the thermal expansion via capacitance dilatometry is a powerful experimental technique, due to the extremely high resolution (ΔL/L∝10 -8 -10 -10 ). With respect to the air sensitivity of the fullerides a dilatometer operating under inert atmosphere was designed and the thermal expansion of polycrystalline fulleride (Rb 3 C 60 , K 3 C 60 ) and borocarbide (YNi 2 B 2 C, LuNi 2 B 2 C) compounds was determined in the temperature range 5-320 K. Most effort was focused on a quantitative evaluation of the discontinuity in the thermal expansivity α at the superconducting transition. The results are discussed in the context of the Ehrenfest relation, which connects the jump in the thermal expansivity Δα with the pressure dependence of the superconducting transition temperature dT c /dp and the jump in the specific heat Δc p /T c at the superconducting transition. For Rb 3 C 60 and K 3 C 60 the jump in the specific heat can be derived via the Ehrenfest relation using the results of the thermal expansion measurements and the well-known pressure dependence of the superconducting transition temperature. The derived values for Rb 3 C 60 and K 3 Cu 60 are Δc p /T c ∝75mJ/molK 2 and Δc p /T c ∝64 mJ.molK 2 , respectively. The directly measured specific heat jump of K 3 C 60 gives approximately the same value of Δc p /T c , and, therefore, the use of the Ehrenfest relation on fullerides is justified. The specific heat jumps Δc p /T c , determined from theoretically derived values of the density of states at the Fermi level N(E F ) and the McMillan-parameter λ, exceed the experimental results by a factor of 1.5-2. This finding reflects the uncertainty concerning the superconducting parameters N(E F ) and λ. (orig.)

  7. [Cyclotron based nuclear science

    International Nuclear Information System (INIS)

    1993-07-01

    The period 1 April 1992--31 March 1993 saw the initial runs of three new spectrometers, which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP) (data from which are shown on the cover of this document), the Mass Achroniat Recoil Mass Spectrometer (MARS), and the Multipole Dipole Multipole (MDM) Particle Spectrometer. The ECR-K500 cyclotron combination operated 5,849 hours. The beam was on target 39% of this time. Studies of nuclear dynamics and nuclear thermodynamics using the neutron ball have come to fruition. A critical re-evaluation of the available data on the giant monopole resonance indicated that the incompressibility is not specified to a range smaller than 200--350 MeV by those data. New systematic experiments using the MDM spectrometer are now underway. The MEGA collaboration obtained the first data on the μ → eγ decay rate and determination of the Michel parameter in normal μ decay. Experiments appear to confirm the existence of monoenergetic pair peaks even for relatively low Z projectile -- Z target combinations. Studies of the (α,2α) knockout reaction indicate that this reaction may prove to be a valuable tool for determination of reaction rates of astrophysical interest. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. New measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported. The research is presented in nearly 50 brief summaries usually including data and references

  8. Playing catch with energy between two superconducting coils

    International Nuclear Information System (INIS)

    Masuda, Masayoshi; Shintomi, Takakazu; Asaji, Kiyoyuki.

    1979-03-01

    The first performance of playing catch with energy between two 100 kJ superconducting magnets has been presented. The mechanism of the energy transfer as an interface between the superconducting coils is a thyristorized DC-AC-DC converter. The obtained experimental efficiency of energy transfer has been compared with the theory and good agreement has been obtained. The method will offer a versatile extension of superconductive technique in energy problems. (author)

  9. Synthesis and characterization of superconducting bismuthates

    International Nuclear Information System (INIS)

    Tang, Horngyi.

    1991-01-01

    A new electrosynthetic technique for low-temperature crystal growth of superconducting bismuthates was developed, and its utility demonstrated by growing various high-quality BiO 3 crystals. The crystals of Ba 1-x K x BiO 3 and Ba 1-x Rb x BiO 3 display their T c onset at 31.8k and 28k, respectively, using SQUID magnetometry. The structure of a KBiO 3 x H 2 O single crystal determined by single crystal x-ray diffraction confirms previous results from powder samples that it is isostructural with KSbO 3 . The crystals of Ba 1-x Cs x BiO 3 do not show superconductivity to 4k. Chemical vapor-transport experiments leading to the fabrication of MoS 2 /WSe 2 junctions were also performed and are described in detail

  10. State-of-the-art superconducting accelerator magnets

    CERN Document Server

    Rossi, L

    2002-01-01

    With the LHC the technology of NbTi-based accelerator magnets has been pushed to the limit. By operating in superfluid helium, magnetic fields in excess of 10 T have been reached in various one meter-long model magnets while full scale magnets, 15 meter-long dipoles, have demonstrated possibility of safe operation in the 8.3-9 tesla range, with the necessary, very tight, field accuracy. The paper reviews the key points of the technology that has permitted the construction of the largest existing superconducting installations (Fermilab, Desy and Brookhaven), highlighting the novelties of the design of the LHC dipoles, quadrupoles and other superconducting magnets. All together the LHC project will need more than 5000 km of fine filament superconducting cables capable of 14 kA @ 10 T, 1.9 K. (13 refs).

  11. Pressure induced superconductivity in the antiferromagnetic Dirac material BaMnBi2.

    Science.gov (United States)

    Chen, Huimin; Li, Lin; Zhu, Qinqing; Yang, Jinhu; Chen, Bin; Mao, Qianhui; Du, Jianhua; Wang, Hangdong; Fang, Minghu

    2017-05-09

    The so-called Dirac materials such as graphene and topological insulators are a new class of matter different from conventional metals and (doped) semiconductors. Superconductivity induced by doing or applying pressure in these systems may be unconventional, or host mysterious Majorana fermions. Here, we report a successfully observation of pressure-induced superconductivity in an antiferromagnetic Dirac material BaMnBi 2 with T c of ~4 K at 2.6 GPa. Both the higher upper critical field, μ 0 H c2 (0) ~ 7 Tesla, and the measured current independent of T c precludes that superconductivity is ascribed to the Bi impurity. The similarity in ρ ab (B) linear behavior at high magnetic fields measured at 2 K both at ambient pressure (non-superconductivity) and 2.6 GPa (superconductivity, but at the normal state), as well as the smooth and similar change of resistivity with pressure measured at 7 K and 300 K in zero field, suggests that there may be no structure transition occurred below 2.6 GPa, and superconductivity observed here may emerge in the same phase with Dirac fermions. Our findings imply that BaMnBi 2 may provide another platform for studying SC mechanism in the system with Dirac fermions.

  12. DAISY - the Oslo Cyclotron data acquisition system

    International Nuclear Information System (INIS)

    Ramsoey, T.

    1991-08-01

    The new CACTUS multidetector system for the Oslo Cyclotron consists of 8 particle telescopes, 28 NAI detectors and 2 Ge detectors. Each detector gives rise to one energy parameter and one time parameter. Thus, a total of 80 parameters are present. The counting rate is 100 kByte/s for the highest beam intensities. A new data acquisition system, DAISY, satisfying these demands has been designed. The present report is intended as a complete technical manual for the new system. 24 refs

  13. Construction of testing facilities and verifying tests of a 22.9 kV/630 A class superconducting fault current limiter

    Science.gov (United States)

    Yim, S.-W.; Yu, S.-D.; Kim, H.-R.; Kim, M.-J.; Park, C.-R.; Yang, S.-E.; Kim, W.-S.; Hyun, O.-B.; Sim, J.; Park, K.-B.; Oh, I.-S.

    2010-11-01

    We have constructed and completed the preparation for a long-term operation test of a superconducting fault current limiter (SFCL) in a Korea Electric Power Corporation (KEPCO) test grid. The SFCL with rating of 22.9 kV/630 A, 3-phases, has been connected to the 22.9 kV test grid equipped with reclosers and other protection devices in Gochang Power Testing Center of KEPCO. The main goals of the test are the verification of SFCL performance and protection coordination studies. A line-commutation type SFCL was fabricated and installed for this project, and the superconducting components were cooled by a cryo-cooler to 77 K in the sub-cooled liquid nitrogen pressurized by 3 bar of helium gas. The verification test includes un-manned - long-term operation with and without loads and fault tests. Since the test site is 170 km away from the laboratory, we will adopt the un-manned operation with real-time remote monitoring and controlling using high speed internet. For the fault tests, we will apply fault currents up to around 8 kArms to the SFCL using an artificial fault generator. The fault tests may allow us not only to confirm the current limiting capability of the SFCL, but also to adjust the SFCL - recloser coordination such as resetting over-current relay parameters. This paper describes the construction of the testing facilities and discusses the plans for the verification tests.

  14. Construction of testing facilities and verifying tests of a 22.9 kV/630 A class superconducting fault current limiter

    International Nuclear Information System (INIS)

    Yim, S.-W.; Yu, S.-D.; Kim, H.-R.; Kim, M.-J.; Park, C.-R.; Yang, S.-E.; Kim, W.-S.; Hyun, O.-B.; Sim, J.; Park, K.-B.; Oh, I.-S.

    2010-01-01

    We have constructed and completed the preparation for a long-term operation test of a superconducting fault current limiter (SFCL) in a Korea Electric Power Corporation (KEPCO) test grid. The SFCL with rating of 22.9 kV/630 A, 3-phases, has been connected to the 22.9 kV test grid equipped with reclosers and other protection devices in Gochang Power Testing Center of KEPCO. The main goals of the test are the verification of SFCL performance and protection coordination studies. A line-commutation type SFCL was fabricated and installed for this project, and the superconducting components were cooled by a cryo-cooler to 77 K in the sub-cooled liquid nitrogen pressurized by 3 bar of helium gas. The verification test includes un-manned - long-term operation with and without loads and fault tests. Since the test site is 170 km away from the laboratory, we will adopt the un-manned operation with real-time remote monitoring and controlling using high speed internet. For the fault tests, we will apply fault currents up to around 8 kA rms to the SFCL using an artificial fault generator. The fault tests may allow us not only to confirm the current limiting capability of the SFCL, but also to adjust the SFCL - recloser coordination such as resetting over-current relay parameters. This paper describes the construction of the testing facilities and discusses the plans for the verification tests.

  15. Superconductivity in Ba sub 1 sub - sub x K sub x BiO sub 3 : possible scenario of spatially separated Fermi-Bose mixture

    CERN Document Server

    Menushenkov, A P; Kuznetsov, A V; Kagan, M Y

    2001-01-01

    A new scenario for the metal-insulator phase transition and superconductivity in the perovskite-like bismuthates Ba sub 1 sub - sub x K sub x BiO sub 3 (BKBO) is proposed. It is shown that two types of charge carriers, the local pairs (real-space bosons) and the itinerant electrons, exist in the metallic compound BKBO (x >= 0.37). The real-space bosons are responsible for the charge transport in semiconducting BaBiO sub 3 and for superconductivity in the metallic BKBO. The appearance of the Fermi-liquid state as the percolation threshold is overcome (x >= 0.37) explains the observed metal-insulator phase transition. Because bosons and fermions occupy different types of the octahedral BiO sub 6 complexes, they are separated in real space, and therefore, the spatially separated Fermi-Bose mixture of a new type is likely to be realized in the bismuthates. The nature of superconductivity is consistently explained in the framework of this scenario. A new superconducting oxide Ba sub 1 sub - sub x La sub x PbO sub ...

  16. Superconducting inductive displacement detection of a microcantilever

    Science.gov (United States)

    Vinante, A.

    2014-07-01

    We demonstrate a superconducting inductive technique to measure the displacement of a micromechanical resonator. In our scheme, a type I superconducting microsphere is attached to the free end of a microcantilever and approached to the loop of a dc Superconducting Quantum Interference Device (SQUID) microsusceptometer. A local magnetic field as low as 100 μT, generated by a field coil concentric to the SQUID, enables detection of the cantilever thermomechanical noise at 4.2 K. The magnetomechanical coupling and the magnetic spring are in good agreement with image method calculations assuming pure Meissner effect. These measurements are relevant to recent proposals of quantum magnetomechanics experiments based on levitating superconducting microparticles.

  17. A line-of-sight electron cyclotron emission receiver for electron cyclotron resonance heating feedback control of tearing modes

    DEFF Research Database (Denmark)

    Oosterbeek, J.W.; Bürger, A.; Westerhof, E.

    2008-01-01

    An electron cyclotron emission (ECE) receiver inside the electron cyclotron resonance heating (ECRH) transmission line has been brought into operation. The ECE is extracted by placing a quartz plate acting as a Fabry-Perot interferometer under an angle inside the electron cyclotron wave (ECW) bea...

  18. Design study for superconducting main field coils for the Oak Ridge Isochronous Cyclotron

    International Nuclear Information System (INIS)

    Schwenterly, S.W.; Litherland, P.S.; Ballou, J.K.

    1981-01-01

    The design study described here demonstrated the feasibility of replacing the existing ORIC coils with superconducting magnets. The design is quite conservative, requires no unusual technology, and should result in a coil system with good reliability and durability. The operating regime of ORIC will be considerably extended, and running costs should be reduced. A proposal to continue with detailed design and coil fabrication is currently under review and has been submitted to the Nuclear Science Advisory Committee

  19. Possibility of high temperature superconducting phases in PdH

    Science.gov (United States)

    Tripodi, Paolo; Di Gioacchino, Daniele; Borelli, Rodolfo; Vinko, Jenny Darja

    2003-05-01

    Possible new superconducting phases with a high critical transition temperature (Tc) have been found in stable palladium-hydrogen (PdHx) samples for stoichiometric ratio x=H/Pd⩾1, in addition to the well-known low critical transition temperature (0⩽Tc⩽9) when x is in the range (0.75⩽x⩽1.00). Possible new measured superconducting phases with critical temperature in the range 51⩽Tc⩽295 K occur. This Tc varies considerably with every milli part of x when x exceeds unit. A superconducting critical current density Jc⩾6.1×104 A cm-2 has been measured at 77 K with HDC=0 T.

  20. Anomalous magnetism of superconducting Mg-doped InN film

    Directory of Open Access Journals (Sweden)

    P. H. Chang

    2016-02-01

    Full Text Available We report on the Meissner effect of Mg-doped InN film with superconducting transition onset temperature Tc,onset of 5 K. Mg-doped InN is magnetically ordered and exhibits a simultaneous first-order magnetic and electric transition near 50 K. Its behavior is similar to that of iron-based superconductors. A strong correlation is proposed to exist between structural distortion and superconductivity when Mg is doped into InN. The suppression of magnetic ordering close to Tc by doping is further demonstrated by anisotropic magnetoresistance and M-H measurements. The findings suggest that the superconducting mechanism in the system may not be conventional BCS.

  1. Method and apparatus for ion cyclotron spectrometry

    Science.gov (United States)

    Dahl, David A [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2010-08-17

    An ion cyclotron spectrometer may include a vacuum chamber that extends at least along a z-axis and means for producing a magnetic field within the vacuum chamber so that a magnetic field vector is generally parallel to the z-axis. The ion cyclotron spectrometer may also include means for producing a trapping electric field within the vacuum chamber that includes at least a first section that induces a first magnetron effect that increases a cyclotron frequency of an ion and at least a second section that induces a second magnetron effect that decreases the cyclotron frequency of an ion. The cyclotron frequency changes induced by the first and second magnetron effects substantially cancel one another so that an ion traversing the at least first and second sections will experience no net change in cyclotron frequency.

  2. Commercial compact cyclotrons in the 90's

    International Nuclear Information System (INIS)

    Milton, B.F.

    1995-09-01

    Cyclotrons continue to be efficient accelerators for radio-isotope production. In recent years, developments in the accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicate a strong future for commercial cyclotrons. In this paper we will survey recent developments in the areas of cyclotron technology, as they relate to the new generation of commercial cyclotrons. Design criteria for the different types of commercial cyclotrons will be presented, with reference to those demands that differ from those in a research oriented cyclotron project. We will also discuss the possibility of systems designed for higher energies and capable of extracted beam currents of up to 2.0 mA. (author)

  3. Commercial compact cyclotrons in the 90's

    International Nuclear Information System (INIS)

    Milton, B.F.

    1995-09-01

    Cyclotrons continue to be efficient accelerators for radio-isotope production. In recent years, developments in the accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicate a strong future for commercial cyclotrons. In this paper the authors will survey recent developments in the areas of cyclotron technology, as they relate to the new generation of commercial cyclotrons. Design criteria for the different types of commercial cyclotrons will be presented, with reference to those demands that differ from those in a research oriented cyclotron project. The authors also discuss the possibility of systems designed for higher energies and capable of extracted beam currents of up to 2.0 mA

  4. Cryogenic safety of the superconducting ALPI accelerator at INFN-LNL

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    The superconducting linac ALPI at INFN-LNL is composed of 20 identical cryostats housing, at a group of four (or two), 74 superconducting QWR type cavities: 58 resonators are made of copper with Nb sputtered on the internal surface and 16 are made of Nb bulk. In each cryostat is installed a 100 liter volume LHe reservoir feeding by gravity the QWR’s. The thermal shield around is cooled by GHe at 6 bar abs at 60-80 K. The linac ALPI is a post-accelerator which can receive heavy ions from either the 16 MV Tandem Van de Graaf or from the superconducting injector PIAVE. The latter is composed by an ECR source, two superconducting RFQ, and two cryostats each containg four superconducting bulk Nb QWR. The ALPI cryostats are cooled by a Helium refrigerator whose refrigerator capacity is 1200 W at 4.5 K and 3900 W additional at 60-80 K. PIAVE cryostats are cooled by a separate TCF50 helium refrigerator. The complex ALPI-PIAVE is installed in a semi-open removable concrete tunnel in the same building where the two h...

  5. Changes of superconducting interaction in interfaces

    International Nuclear Information System (INIS)

    Halbritter, J.

    1976-01-01

    The leakage of conduction electrons from metals into dielectric or semiconducting coatings yields changes in electron phonon coupling and hybridization with localized states in the coating. The changed electron-phonon coupling explains the observed strengthened superconducting interaction with some monolayer thick coating. The hybridization with localized states, i.e. resonance scattering, yields pair weakening and hence a monotonic depression of superconductivity with coating thickness in agreement with experiments. The latter effect explains quantitatively the Tsub(c) and Δ depression (Δ/kTsub(c) approximately equal to const) and a decrease in the Maki-Thompson-fluctuation term observed with thin superconducting films. (author)

  6. Ion-cyclotron-resonance- and Fourier-transform-ion-cyclotron-resonance spectroscopy: technology and application

    International Nuclear Information System (INIS)

    Luederwald, I.

    1977-01-01

    Instrumentation and technology of Ion-Cyclotron-Resonance and Fourier-Transform-Ion-Cyclotron-Resonance Spectroscopy are described. The method can be applied to studies of ion/molecule reactions in gas phase, to obtain thermodynamic data as gas phase acidity or basicity, proton and electron affinity, and to establish reaction mechanisms and ion structures. (orig.) [de

  7. Ceramic superconductor/metal composite materials employing the superconducting proximity effect

    Science.gov (United States)

    Holcomb, Matthew J.

    2002-01-01

    Superconducting composite materials having particles of superconducting material disposed in a metal matrix material with a high electron-boson coupling coefficient (.lambda.). The superconducting particles can comprise any type of superconductor including Laves phase materials, Chevrel phase materials, A15 compounds, and perovskite cuprate ceramics. The particles preferably have dimensions of about 10-500 nanometers. The particles preferably have dimensions larger than the superconducting coherence length of the superconducting material. The metal matrix material has a .lambda. greater than 0.2, preferably the .lambda. is much higher than 0.2. The metal matrix material is a good proximity superconductor due to its high .lambda.. When cooled, the superconductor particles cause the metal matrix material to become superconducting due to the proximity effect. In cases where the particles and the metal matrix material are chemically incompatible (i.e., reactive in a way that destroys superconductivity), the particles are provided with a thin protective metal coating. The coating is chemically compatible with the particles and metal matrix material. High Temperature Superconducting (HTS) cuprate ceramic particles are reactive and therefore require a coating of a noble metal resistant to oxidation (e.g., silver, gold). The proximity effect extends through the metal coating. With certain superconductors, non-noble metals can be used for the coating.

  8. 100 Years of Superconductivity: Perspective on Energy Applications

    Science.gov (United States)

    Grant, Paul

    2011-11-01

    One hundred years ago this past April, in 1911, traces of superconductivity were first detected near 4.2 K in mercury in the Leiden laboratory of Kammerlingh Onnes, followed seventy-five years later in January, 1986, by the discovery of ``high temperature'' superconductivity above 30 K in layered copper oxide perovskites by Bednorz and Mueller at the IBM Research Laboratory in Rueschlikon. Visions of application to the electric power infrastructure followed each event, and the decades following the 1950s witnessed numerous, successful demonstrations to electricity generation, transmission and end use -- rotating machinery, cables, transformers, storage, current limiters and power conditioning, employing both low and high temperature superconductors in the USA, Japan, Europe, and more recently, China. Despite these accomplishments, there has been to date no substantial insertion of superconducting technology in the electric power infrastructure worldwide, and its eventual deployment remains problematic. We will explore the issues delaying such deployment and suggest future electric power scenarios where superconductivity will play an essential central role.

  9. RF control hardware design for CYCIAE-100 cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhiguo, E-mail: bitbearAT@hotmail.com; Fu, Xiaoliang; Ji, Bin; Zhao, Zhenlu; Zhang, Tianjue; Li, Pengzhan; Wei, Junyi; Xing, Jiansheng; Wang, Chuan

    2015-11-21

    The Beijing Radioactive Ion-beam Facility project is being constructed by BRIF division of China Institute of Atomic Energy. In this project, a 100 MeV high intensity compact proton cyclotron is built for multiple applications. The first successful beam extraction of CYCIAE-100 cyclotron was done in the middle of 2014. The extracted proton beam energy is 100 MeV and the beam current is more than 20 μA. The RF system of the CYCIAE-100 cyclotron includes two half-wavelength cavities, two 100 kW tetrode amplifiers and power transmission line systems (all above are independent from each other) and two sets of Low Level RF control crates. Each set of LLRF control includes an amplitude control unit, a tuning control unit, a phase control unit, a local Digital Signal Process control unit and an Advanced RISC Machines based EPICS IOC unit. These two identical LLRF control crates share one common reference clock and take advantages of modern digital technologies (e.g. DSP and Direct Digital Synthesizer) to achieve closed loop voltage and phase regulations of the dee-voltage. In the beam commission, the measured dee-voltage stability of RF system is better than 0.1% and phase stability is better than 0.03°. The hardware design of the LLRF system will be reviewed in this paper.

  10. Theory of the current-driven ion cyclotron instability in the bottomside ionosphere

    International Nuclear Information System (INIS)

    Satyanarayana, P.; Chaturvedi, P.K.; Keskinen, M.J.; Huba, J.D.; Ossakow, S.L.

    1985-01-01

    A theory of the current-driven electrostatic ion cyclotron (EIC) instability in the collisional bottomside ionosphere is presented. It is found that electron collisions are destabilizing and are crucial for the excitation of the EIC instability in the collisional bottomside ionosphere. Furthermore, the growth rates of the ion cyclotron instability in the bottomside ionosphere maximize for k/sub perpendicular/ rho/sub i/> or =1, where 2π/k/sub perpendicular/ is the mode scale size perpendicular to the magnetic field and rho/sub i/ the ion gyroradius. Realistic plasma density and temperature profiles typical of the high-latitude ionosphere are used to compute the altitude dependence of the linear growth rate of the maximally growing modes and critical drift velocity of the EIC instability. The maximally growing modes correspond to observed tens of meter size irregularities, and the threshold drift velocity required for the excitation of EIC instability is lower for heavier ions (NO + , O + ) than that for the lighter ions (H + ). Dupree's resonance-broadening theory is used to estimate nonlinear saturated amplitudes for the ion cyclotron instability in the high-latitude ionosphere. Comparison with experimental observations is also made. It is conjectured that the EIC instability in the bottomside ionosphere could be a source of transversely accelerated heavier ions and energetic heavy-ion conic distributions at higher altitudes

  11. Developing the smallest possible medical cyclotron

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Imagine a portable medical cyclotron operated in a conventional radioactive facility at a hospital. Imagine a nurse or technician switching it on and producing isotopes at the patient’s bedside. Sounds like science fiction? Think again.   CERN has teamed up with Spain’s national scientific research centre (CIEMAT) to develop an avant-garde cyclotron to be used for Positron Emission Tomography (PET). “We plan to make a cyclotron that doesn't need an insulated building or ‘vault’: a cyclotron small enough to fit inside a hospital lift,” explains Jose Manuel Perez, who is leading the CIEMAT/CERN collaboration. “It will be the smallest possible medical cyclotron for single patient dose production and will dramatically reduce costs for hospitals.” While PET technology has transformed imaging techniques, many of its medical benefits have remained confined to highly specialised hospitals. “Studies have foun...

  12. Loss-cone-driven ion cyclotron waves in the magnetosphere

    International Nuclear Information System (INIS)

    Denton, R.E.; Hudson, M.K.; Roth, I.

    1992-01-01

    The theoretical properties of linear ion cyclotron waves propagating in the magnetosphere at arbitrary angles to the background magnetic field are explored. It is found that in some cases the linear wave growth of modes with oblique propagation can dominate that of the parallel propagating electromagnetic ion cyclotron (EMIC) wave. In particular, when the hot ring current protons have a loss cone and their temperature anisotropy A ≡ T perpendicular /T parallel - 1 is reduced, the parallel propagating EMIC wave becomes stable, while the obliquely propagating loss-cone-driven mode persists. The growth rate of the loss-cone-driven model depends strongly on the depth of the loss cone. Unlike the parallel propagating EMIC wave, it can be unstable with A = 0. Other conditions that favor the loss-cone-driven mode in comparison to the parallel mode are stronger background magnetic field, lower density of cold hydrogen, and a lower temperature for the hot anisotropic component of hydrogen. A simple analytical theory is presented which explains the scaling of the growth rate of the oblique mode with respect to various parameters. The loss-cone-driven mode is an electromagnetic mode which is preferentially nearly linearly polarized. It is nearly electrostatic in the sense that the wave electric field is aligned with the perpendicular (to B 0 ) component of the wave vector k and k perpendicular > k parallel . Since the electric and magnetic wave fields are perpendicular to B 0 , they would be difficult to distinguish from those of a linearly polarized parallel propagating electromagnetic wave with the same k parallel

  13. Development of superconducting ship propulsion system

    International Nuclear Information System (INIS)

    Sakuraba, Junji; Mori, Hiroyuki; Hata, Fumiaki; Sotooka, Koukichi

    1991-01-01

    When we plan displacement-type monohull high speed vessels, it is difficult to get the hull form with the wave-making resistance minimum, because the stern shape is restricted by arrangement of propulsive machines and shafts. A small-sized and light-weight propulsive machines will reduce the limit to full form design. Superconducting technology will have capability of realizing the small-sized and light-weight propulsion motor. The superconducting electric propulsion system which is composed of superconducting propulsion motors and generators, seems to be an ideal propulsion system for future vehicles. We have constructed a 480 kW superconducting DC homopolar laboratory test motor for developing this propulsion system. The characteristic of this motor is that it has a superconducting field winding and a segmented armature drum. The superconducting field winding which operates in the persistent current mode, is cooled by a condensation heat exchanger and helium refigerating system built into the cryostat of the superconducting field winding. The operating parameters of this motor agreed well with the design parameters. Using the design concepts of this motor, we have conceptually designed a 150,000-200,000 PS superconducting electric propulsive system for a displacement-type monohull high speed ship. (author)

  14. Proton beam therapy: reliability of the synchrocyclotron at the Harvard Cyclotron Laboratory

    International Nuclear Information System (INIS)

    Sisterson, J.M.; Cascio, E.; Koehler, A.M.; Johnson, K.N.

    1991-01-01

    The reliability of the synchrocyclotron at Harvard Cyclotron Laboratory has been studied over the period 1980-1989 to see if proton beam therapy can compare in reliability to linear accelerators used in radiation therapy departments. Breakdowns in relation to patient load are reviewed in outline. (U.K.)

  15. Thermal history dependence of superconducting properties in La2CuO4+δ

    International Nuclear Information System (INIS)

    Hirayama, T.; Nakagawa, M.; Sumiyama, A.; Oda, Y.

    1998-01-01

    We studied the thermal history dependence of the superconducting properties below/above room temperature (RT) in the ceramic La 2 CuO 4-δ with excess oxygen. The phase separation (O-rich phase: superconducting and O-poor phase: antiferromagnetic) was concluded to occur above 373 K, in contrast with the usual report of the phase separation around 320 K. As for the superconducting phases, the well-known T c onset of 32 or 36 K, dependent on thermal history around 200 K, in the samples annealed in high-pressure oxygen gas, was not changed by thermal history between RT and 373 K. The samples electrochemically oxidized at RT included the phase with the high T c of 45 K, which was not changed by thermal history below RT, and the phase with the low T c of 32 or 36 K. The 45 K phase was changed into the low-T c phase by annealing at 373 K. The samples electrochemically oxidized at 333 K, which was accompanied with the diffusion of excess oxygen, showed gradual change of superconducting behavior: the single low-T c (32 or 36 K) phase (oxidation time = 24 h), coexistence of the low-T c phase and the high-T c (45 K) phase (36 h), and the single high T c phase (48 and 72 h). Thus, the single superconducting phase with the high T c of 45 K has been obtained, which showed a metallic behavior in normal resistivity and apparent changes of lattice constant in comparison with that of stoichiometric La 2 CuO 4 . (orig.)

  16. Acceleration of tritons with a compact cyclotron

    International Nuclear Information System (INIS)

    Wegmann, H.; Huenges, E.; Muthig, H.; Moringa, H.

    1981-01-01

    With the compact cyclotron at the Faculty of Physics of the Technical University of Munich, tritons have been accelerated to an energy of 7 MeV. A safe and reliable operation of the gas supply for the ion source was obtained by a new tritium storage system. A quantity of 1500 Ci tritium is stored by two special Zr-Al getter pumps in a non-gaseous phase. The tritium can be released in well-defined amounts by heating the getter material. During triton acceleration the pressure in the cyclotron vacuum chamber is maintained only by a large titanium sputter-ion pump, thus forming a closed vacuum system without any exhaust of tritium contaminated gas. Any tritium contaminations in the air can be detected by an extremely sensitive tritium monitoring system. The triton beam with a maximum intensity of 30 μA has been used so far to produce neutron-rich radioisotopes such as 28 Mg, 43 K, or 72 Zn, which are successfully applied in tracer techniques in the studies of biological systems. (orig.)

  17. Medical cyclotron basic concepts and its applications

    International Nuclear Information System (INIS)

    Kumar, Rajeev; Sonkawade, R.G.

    2012-01-01

    More than 3000 nuclides are known, of which approximately 2700 are radioactive, and rest are stable. The majority of radionuclides are artificially produced in the reactor and cyclotron. In a cyclotron, Charge particle such as proton, Deuteron, á (Alpha) particle, 3 He particles and so forth are accelerated in circular paths within the Dees under vacuum by means of an electromagnetic field. These accelerated particles can possess few KeV to several BeV of kinetic energy depending on the design of the cyclotron. At our setup we have an 11 MeV dual beam multi target cyclotron which is capable producing 11 C, 13 N, 15 O, 18 F and 2 F radioisotopes and all have been successfully produced and tested in our lab. Earlier cyclotrons were the best source of high-energy beams for nuclear physics experiments; several cyclotrons are still in use for this type of research. Cyclotrons can be used to treat cancer. Ion beams from cyclotrons can be used, as in proton therapy. The positron emitting isotopes are suitable for PET imaging. As discussed we are producing mainly Carbon-11, Nitrogen-13, Oxygen-15, and Fluorine-18: These are positron emitters used in PET for studying brain physiology and pathology, in particular for localizing epileptic focus, and in dementia, psychiatry and neuropharmacology studies. So these are having significant role in diagnosis of Oncological, Neurological and Cardiological disorder. More than ninety percent we are producing 18 F in FDG. 18 F in FDG (Flouro-Deoxy-glucose) has become very important in detection of cancers and the monitoring of progress in their treatment, using PET. Medical cyclotron is complex equipment requiring delicate handling by highly trained personnel. The aim of this article is to highlight few finer aspects of Medical cyclotron operation, including precautions for safety and smooth functioning of this sophisticated equipment. (author)

  18. Application of distantiometric protections to 500 kV lines with AL 100% series compensation; Aplicacion de protecciones distanciometricas a lineas de 500 kV con compensacion serie AL 100%

    Energy Technology Data Exchange (ETDEWEB)

    Gaudio, Juan Carlos; Pesce, Jose Juan O.; Faure, Carlos Hugo [TRANSENER S.A., Buenos Aires (Argentina)

    2001-07-01

    The TRANSENER S.A. viewing the rising of the transmission capacity of the Northeastern Argentine Generators, assumed the installation costs of compensation by series capacitors. In the middle of the year 2000 was put into service a series capacitor bank on the extremity Recreo of the 500 kV to the Malvinas Argentina of the TRANSENER S.A.. The reactance compensation of the line in about 100% was responsible by the necessity of replacing the existent analogic electronic protection by new numerical distantiometric protections on the El Bracho and Malvinas Argentinas transformer station. This paper presents the imposed conditions for the selected line protection, the prior studies posterior the mentioned selection for validating the application, and the difficulties necessary to the task performing as well.

  19. Parameter design and performance simulation of a 10 kV voltage compensation type active superconducting fault current limiter

    International Nuclear Information System (INIS)

    Chen, L.; Tang, Y.J.; Song, M.; Shi, J.; Ren, L.

    2013-01-01

    Highlights: •For a practical 10 kV system, the 10 kV active SFCL’s basic parameters are designed. •Under different fault conditions, the 10 kV active SFCL’s performances are simulated. •The designed 10 kV active SFCL’s engineering feasibility is discussed preliminarily. -- Abstract: Since the introduction of superconducting fault current limiter (SFCL) into electrical distribution system may be a good choice with economy and practicability, the parameter design and current-limiting characteristics of a 10 kV voltage compensation type active SFCL are studied in this paper. Firstly, the SFCL’s circuit structure and operation principle are presented. Then, taking a practical 10 kV distribution system as its application object, the SFCL’s basic parameters are designed to meet the system requirements. Further, using MATLAB, the detailed current-limiting performances of the 10 kV active SFCL are simulated under different fault conditions. The simulation results show that the active SFCL can deal well with the faults, and the parameter design’s suitability can be testified. At the end, in view of the engineering feasibility of the 10 kV active SFCL, some preliminary discussions are carried out

  20. Korea's developmental program for superconductivity

    Science.gov (United States)

    Hong, Gye-Won; Won, Dong-Yeon; Kuk, Il-Hyun; Park, Jong-Chul

    1995-04-01

    Superconductivity research in Korea was firstly carried out in the late 70's by a research group in Seoul National University (SNU), who fabricated a small scale superconducting magnetic energy storage system under the financial support from Korea Electric Power Company (KEPCO). But a few researchers were involved in superconductivity research until the oxide high Tc superconductor was discovered by Bednorz and Mueller. After the discovery of YBaCuO superconductor operating above the boiling point of liquid nitrogen (77 K)(exp 2), Korean Ministry of Science and Technology (MOST) sponsored a special fund for the high Tc superconductivity research to universities and national research institutes by recognizing its importance. Scientists engaged in this project organized 'High Temperature Superconductivity Research Association (HITSRA)' for effective conducting of research. Its major functions are to coordinate research activities on high Tc superconductivity and organize the workshop for active exchange of information. During last seven years the major superconductivity research has been carried out through the coordination of HITSRA. The major parts of the Korea's superconductivity research program were related to high temperature superconductor and only a few groups were carrying out research on conventional superconductor technology, and Korea Atomic Energy Research Institute (KAERI) and Korea Electrotechnology Research Institute (KERI) have led this research. In this talk, the current status and future plans of superconductivity research in Korea will be reviewed based on the results presented in interim meeting of HITSRA, April 1-2, 1994. Taejeon, as well as the research activity of KAERI.

  1. On the automatic control of the ITER ion cyclotron system

    Energy Technology Data Exchange (ETDEWEB)

    Bosia, G. [Department of General Physics, University of Turin, Via P. Giuria 1, 10 125 Turin (Italy)], E-mail: giuseppe.bosia@to.infn.it

    2007-10-15

    The ITER ion cyclotron heating system requires an efficient control system capable of: (i) providing the desired array radiation spectrum, to optimize plasma coupling and absorption and to minimize parasitic power losses in the plasma edge; (ii) maintaining the RF power flow to the plasma against significant load variations, including fast fluctuations induced by ELMs; (iii) reliably detecting and suppressing RF voltage breakdowns in the array and/or in the transmission system, to avoid local equipment damage and (iv) implementing an accurate real time record of performance. In this paper specific aspects of the tuning control system, related to recent conceptual and engineering effort [K. Vulliez, et al., Design of the ITER ion cyclotron heating launcher based on in-vessel tuning system, Article ID106C, this conference] are addressed.

  2. Ion extraction in the cyclotron geometry

    International Nuclear Information System (INIS)

    Rodenburg, R.E.

    1985-01-01

    The detailed physics of ion beam extraction from a plasma column by intense sinusoidal radio frequency (rf) electric fields at the ion cyclotron frequency omega/sub ci/ and its harmonics is experimentally studied. Results describe the instantaneous relationship - within one rf period of approx. = 3009 nsec - between applied rf, the plasma response and the ions expelled by rf and plasma fields. Reflex discharges in H 2 , D 2 , and He with ion and electron densities greater than or equal to10 11 cm -3 are subjected to 0-5 kV zero-to-peak rf electric fields E vector and 0.65-9.00 kG background magnetic fields B 0 vector with E vector perpendicular to B 0 vector. Ion currents up to 200 μA are extracted. Nonperturbing optical diagnostics measure the relative amplitude and phase of instantaneous ion and electron density fluctuations induced by the rf during each rf cycle and the time variation of extracted ion bursts, the latter made possible by the use of a phosphor beam-stop. Detailed dependences on external electric and magnetic fields are reported. The plasma density fluctuations are in good agreement with the dispersion relation for electrostatic ion cyclotron waves (EICW), and the beam data show current enhancement at the second harmonic over that at the fundamental and evidence for a radically different mechanism for the rf-driven ion extraction process than conventional wisdom assumes. This work represents the first detailed, systematic study of the ac ion extraction process

  3. Superconductivity in the Nb-Ru-Ge σ phase

    Science.gov (United States)

    Carnicom, Elizabeth M.; Xie, Weiwei; Sobczak, Zuzanna; Kong, Tai; Klimczuk, Tomasz; Cava, R. J.

    2017-12-01

    We show that the previously unreported ternary σ -phase material N b20.4R u5.7G e3.9 (N b0.68R u0.19G e0.13 ) is a superconductor with a critical temperature of 2.2 K. Temperature-dependent magnetic susceptibility, resistance, and specific-heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for N b20.4R u5.7G e3.9 is 91 mJ mol f .u .-1K-2 (˜3 mJ mol ato m-1K-2 ) and the specific-heat anomaly at the superconducting transition, Δ C /γ Tc , is approximately 1.38. The zero-temperature upper critical field [μ0H c2(0 ) ] was estimated to be 2 T by resistance data. Field-dependent magnetization data analysis estimated μ0H c1(0 ) to be 5.5 mT. Thus, the characterization shows N b20.4R u5.7G e3.9 to be a type-II BCS superconductor. This material appears to be the first reported ternary phase in the Nb-Ru-Ge system, and the fact that there are no previously reported binary Nb-Ru, Nb-Ge, or Ru-Ge σ phases shows that all three elements are necessary to stabilize the material. An analogous σ phase in the Ta-Ru-Ge system did not display superconductivity above 1.7 K, which suggests that electron count cannot govern the superconductivity observed. Preliminary characterization of a possible superconducting σ phase in the Nb-Ru-Ga system is also reported.

  4. 20 years Rossendorf cyclotron

    International Nuclear Information System (INIS)

    1978-08-01

    On the occasion of the 20th anniversary of initiating of the Rossendorf cyclotron accounts are given of most important works and results in the field of accelerator engineering and utilization of this machine. The reports show the trend of development and actual spectrum of application. The enclosed literature lists give a survey of technical and experimental works at cyclotron. (author)

  5. Use of a High-Temperature Superconducting Coil for Magnetic Energy Storage

    International Nuclear Information System (INIS)

    Fagnard, J-F; Crate, D; Jamoye, J-F; Laurent, Ph; Mattivi, B; Cloots, R; Ausloos, M; Genon, A; Vanderbemden, Ph

    2006-01-01

    A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing temperatures down to 17.2 K to be achieved. The temperature dependence of coil electrical resistance R(T) shows a superconducting transition at T = 102.5 K. Measurements of the V(I) characteristics were performed at several temperatures between 17.2 K and 101.5 K to obtain the temperature dependence of the critical current (using a 1 μV/cm criterion). Critical currents were found to exceed 100 A for T < 30 K. An electronic DC-DC converter was built in order to control the energy flow in and out of the superconducting coil. The converter consists of a MOS transistor bridge switching at a 80 kHz frequency and controlled with standard Pulse Width Modulation (PWM) techniques. The system was tested using a 30 V squared wave power supply as bridge input voltage. The coil current, the bridge input and output voltages were recorded simultaneously. Using a 10 A setpoint current in the superconducting coil, the whole system (coil + DC-DC converter) can provide a stable output voltage showing uninterruptible power supply (UPS) capabilities over 1 s

  6. Sample of superconducting wiring from the LHC

    CERN Multimedia

    The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair. The cables carry up to 12’500 amps and must withstand enormous electromagnetic forces. At full field, the force on one metre of magnet is comparable to the weight of a jumbo jet. Coil winding requires great care to prevent movements as the field changes. Friction can create hot spots wh...

  7. On the superconducting state in Ba0.6K0.4BiO3 perovskite oxide

    Science.gov (United States)

    Szcześniak, D.; Kaczmarek, A. Z.; Drzazga, E. A.; Szewczyk, K. A.; Szcześniak, R.

    2018-05-01

    We report study on the superconducting state in Ba0.6K0.4BiO3 (BKBO) perovskite oxide, motivated by the inconclusive results on the pairing mechanism in this compound. Our investigations are conducted within the Migdal-Eliashberg formalism, to account for the phonon-mediated superconducting phase. The considered doping level of the discussed material corresponds to the highest critical temperature in this compound, and allows simultaneous analysis of the oxygen isotope effect, for the O16 and O18 isotopes, respectively. We found that such effect is particularly visible for the critical values of the Coulomb pseudopotential (μC⋆) , which equals to 0.18 for the O16 and 0.16 for the O18 isotope in BKBO. Moreover, we determine the size of the superconducting energy band gap (Δg) and note that obtained values (9.68 meV and 9.55 meV for the O16 and O18, respectively) are in good agreement with the experimental predictions which give Δg ∼ 8.68 meV . Finally, we calculate the characteristic dimensionless parameters, such as the zero-temperature energy gap to the critical temperature, the ratio for the specific heat, as well as the ratio associated with the zero-temperature thermodynamic critical field, which suggest occurrence of the strong-coupling and retardation effects within the phonon-mediated scenario in the analyzed material. Where possible the dimensionless ratios are compared to the experimental estimates, and agrees with these which account for the strong-coupling character of the BKBO superconductor.

  8. Thermal optimum analyses and mechanical design of 10-kA, vapor-cooled power leads for SSC superconducting magnet tests at MTL

    International Nuclear Information System (INIS)

    Shu, Q.S.; Demko, J.; Dorman, R.; Finan, D.; Hatfield, D.; Syromyatnikov, I.; Zolotov, A.; Mazur, P.; Peterson, T.

    1992-08-01

    The spiral-fin, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. In order to thermally optimize the parameters of the power leads, the lead diameters-which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials-were determined. The cryogenic refrigeration and liquefaction loads for supporting the leads have also been calculated. The optimum operational condition with different currents is discussed. An improved mechanical design of the 10-kA power leads was undertaken, with careful consideration of the cryogenic and mechanical performance. In the design, a new thermal barrier device to reduce heat conduction from the vacuum and gas seal area was employed. Therefore, the electric insulation assembly, which isolates the ground potential parts of the lead from the high-power parts, was moved into a warm region in order to prevent vacuum and helium leakage in the 0-ring seals due to transient cold temperature. The instrumentation for testing the power leads is also discussed

  9. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken [Railway Technical Research Institute, 2-8-38 Hikari-cho, Kokubunji-shi, Tokyo 185-8540 (Japan)

    2010-11-15

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  10. Levitation properties of superconducting magnetic bearings using superconducting coils and bulk superconductors

    International Nuclear Information System (INIS)

    Arai, Yuuki; Seino, Hiroshi; Nagashima, Ken

    2010-01-01

    We have been developing a flywheel energy storage system (FESS) with 36 MJ energy capacity for a railway system with superconducting magnetic bearings (SMBs). We prepared two kinds of models using superconducting coils and bulk superconductors (SCs). One model demonstrated SMB load capacity of 20 kN and the other model proved non-contact stable levitation and non-contact rotation with SMBs. Combining these results, the feasibility of a 36 MJ energy capacity FESS with SMBs completely inside a cryostat has been confirmed. In this paper, we report the levitation properties of SMBs in these models.

  11. Inhomogeneities and superconductivity in poly-phase Fe-Se-Te systems

    Science.gov (United States)

    Hartwig, S.; Schäfer, N.; Schulze, M.; Landsgesell, S.; Abou-Ras, D.; Blum, Ch. G. F.; Wurmehl, S.; Sokolowski, A.; Büchner, B.; Prokeš, K.

    2018-02-01

    The impact of synthesis conditions, post-preparation heating procedure, aging and influence of pressure on the superconducting properties of FeSe0.4Te0.6 crystals is reported. Two FeSe0.4Te0.6 single crystals were used in the study, prepared from stoichiometric melt but cooled down with very different cooling rates, and investigated using magnetic bulk and electrical-resistivity methods. The fast-cooled crystal contains large inclusions of Fe3Se2.1Te1.8 and exhibits bulk superconductivity in its as-prepared state, while the other is homogeneous and shows only traces of superconductivity. AC susceptibility measurements under hydrostatic pressure show that the superconducting transition temperature of the inhomogeneous crystal increases from 12.3 K at ambient pressure to Tsc = 17.9 K at 9 kbar. On the other hand, neither pressure nor mechanically-induced stress is sufficient to induce superconductivity in the homogeneous crystal. However, an additional heat treatment at 673 K followed by fast cooling down and/or long-term aging at ambient conditions leads to the appearance of bulk superconductivity also in the latter sample. This sample remains homogeneous on a scale down to few μm but shows an additional magnetic phase transition around 130 K suggesting that it must be inhomogeneous. For comparison also Fe3Se2.1Te1.8 polycrystals have been prepared and their magnetic properties have been studied. It appears that this phase is not superconducting by itself. It is concluded that nano-scale inhomogeneities that appear in the FeSexTe1-x system due to a spinodal decomposition in the solid state are necessary for bulk superconductivity, possibly due to minor changes in the crystal structure and microstructure. Macroscopic inclusions quenched by fast cooling from high temperatures lead obviously to strain and hence variations in the lattice constants, an effect that is further supported by application of pressure/stress.

  12. Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Tsuyoshi [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-30

    This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e⁺/e⁻ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.

  13. Introduction to Superconducting RF Structures and the Effect of High Pressure Rinsing

    International Nuclear Information System (INIS)

    Tajima, Tsuyoshi

    2016-01-01

    This presentation begins by describing RF superconductivity and SRF accelerating structures. Then the use of superconducting RF structures in a number of accelerators around the world is reviewed; for example, the International Linear Collider (ILC) will use ~16,000 SRF cavities with ~2,000 cryomodules to get 500 GeV e@@@/e@@@ colliding energy. Field emission control was (and still is) a very important practical issue for SRF cavity development. It has been found that high-pressure ultrapure water rinsing as a final cleaning step after chemical surface treatment resulted in consistent performance of single- and multicell superconducting cavities.

  14. High resolution beam line of the U400M cyclotron and RIB accumulation and cooling in the K4 storage ring

    International Nuclear Information System (INIS)

    Rodin, A.M.; Sidorchuk, S.I.; Stepantsov, S.V.

    1996-01-01

    The high resolution beam line ACCULINNA put into operation on a primary beam line of the JINR U400M cyclotron is discussed in the framework of the TREBLE project. The capability of the beam line for producing radioactive ion beams is demonstrated by means of nuclear fragmentation of the primary 14 N beam, with the energy of 51 MeV · A, on the 170 mg/cm 2 carbon target. Characteristics of the obtained 6 He, 8 He and 8 B radioactive beams are presented. A scheme of accumulation and cooling on the orbit of the storage ring K4 is proposed for a low intensity radioactive beam obtained from this beam line. 8 refs., 6 figs., 1 tab

  15. Medical cyclotrons

    International Nuclear Information System (INIS)

    Wolf, A.P.

    1976-01-01

    Cyclotrons as tools for therapy and for the production of radionuclides for use in nuclear medicine have been extensively reviewed in the literature. The current world status with respect to cyclotrons used primarily for research, development and application in nuclear medicine is reviewed here in the context of geographical distribution and type of use, presently available commercial types, machine characteristics and trends. Aspects of design requirements from a user perspective such as machine, beam and target characteristics are covered. Some special problems concerning many factors which can lead to effective production of the desired radionuclide or product are considered in light of machine characteristics. Consideration is also given to future directions for accelerators in nuclear medicine

  16. Calendar aging of a 250 kW/500 kWh Li-ion battery deployed for the grid storage application

    Science.gov (United States)

    Kubiak, Pierre; Cen, Zhaohui; López, Carmen M.; Belharouak, Ilias

    2017-12-01

    The introduction of Li-ion batteries for grid applications has become evidence as the cost per kWh is continuously decreasing. Although the Li-ion battery is a mature technology for automotive applications and portable electronics, its use for stationary applications needs more validation. The Li-ion technology is considered safe enough for grid storage application, but its lifetime is generally evaluated to be around 10 years. Higher market penetration will be achieved if a longer lifespan could be demonstrated. Therefore, aging evaluation of the batteries becomes crucial. In this paper we investigated the effects of aging after a three years' standby field deployment of a 250 kW/500 kWh Li-ion battery integrated with the grid and solar farm under the harsh climate conditions of Qatar. The development of tools for acquisition and analysis of data from the battery management system (BMS) allows the assessment of the battery performance at the battery stack, string and cell levels. The analysis of the residual capacity after aging showed that the stack suffered from a low decrease of capacity, whereas some inconsistencies have been found between the strings. These inconsistencies are caused by misalignment of a small number of cells that underwent self-discharge during standby at high state of charge.

  17. Recent improvements of the tandem facility at LNS

    International Nuclear Information System (INIS)

    Ciavola, G.; Calabretta, L.; Cuttone, G.; Gammino, S.; Raia, G.; Rifuggiato, D.; Rovelli, A.; Scuderi, V.

    1993-01-01

    The Laboratorio Nazionale del Sud (LNS) of Catania is equipped with an upgraded 15 MV SMP tandem that is going to be coupled to a k=800 superconducting cyclotron. The status of the facility and the performances of the upgraded tandem are presented. (orig.)

  18. Magnetic Parameters Of A NB3SN Superconducting Magnet For A 56 HGz ECR Ion Source

    International Nuclear Information System (INIS)

    Ferracin, P.; Caspi, S.; Felice, H.; Leitner, D.; Lyneis, C.M.; Prestemon, S.; Sabbi, G.L.; Todd, D.S.

    2009-01-01

    Third generation Electron Cyclotron Resonance (ECR) ion sources operate at microwave frequencies between 20 and 30 GHz and employ NbTi superconducting magnets with a conductor peak field of 6-7 T. A significant gain in performance can be achieved by replacing NbTi with Nb 3 Sn, allowing solenoids and sextupole coils to reach a field of 15 T in the windings. In this paper we describe the design of a Nb 3 Sn superconducting magnet for a fourth generation ECR source operating at a microwave frequency of 56 GHz. The magnet design features a configuration with an internal sextupole magnet surrounded by three solenoids. A finite element magnetic model has been used to investigate conductor peak fields and the operational margins. Results of the numerical analysis are presented and discussed.

  19. MAGNETIC PARAMETERS OF A NB3SN SUPERCONDUCTING MAGNET FOR A 56 HGz ECR ION SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Ferracin, P.; Caspi, S.; Felice, H.; Leitner, D.; Lyneis, C. M.; Prestemon, S.; Sabbi, G. L.; Todd, D. S.

    2009-05-04

    Third generation Electron Cyclotron Resonance (ECR) ion sources operate at microwave frequencies between 20 and 30 GHz and employ NbTi superconducting magnets with a conductor peak field of 6-7 T. A significant gain in performance can be achieved by replacing NbTi with Nb{sub 3}Sn, allowing solenoids and sextupole coils to reach a field of 15 T in the windings. In this paper we describe the design of a Nb{sub 3}Sn superconducting magnet for a fourth generation ECR source operating at a microwave frequency of 56 GHz. The magnet design features a configuration with an internal sextupole magnet surrounded by three solenoids. A finite element magnetic model has been used to investigate conductor peak fields and the operational margins. Results of the numerical analysis are presented and discussed.

  20. A new structure of superconducting magnetic system for 50 GHz operations (invited).

    Science.gov (United States)

    Xie, D Z

    2012-02-01

    High field and high frequency have been leading the development of electron cyclotron resonance ion sources (ECRISs) in the past decade as demonstrated by the achieved great performance. The present superconducting magnet structures built with NbTi wires have reached an axial field of 3.5-4.0 T and a radial field of 2.0 T for operating frequency up to 28 GHz. Further increase of the magnetic field strength will require higher current superconductor, i.e., Nb(3)Sn wires. This paper will present the features of a new superconducting magnet structure and review of the existing structures. Using NbTi wires, the new magnet structure could be able to produce maximum fields of 7.0 T on axis and radial field of 3.7 T at a hexagonal plasma chamber wall for ECRIS operations up to 50 GHz. If this new magnet can be built with Nb(3)Sn wires, much higher fields can be expected.