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Sample records for normal conducting linac

  1. Computation of Normal Conducting and Superconducting Linear Accelerator (LINAC) Availabilities

    International Nuclear Information System (INIS)

    Haire, M.J.

    2000-01-01

    A brief study was conducted to roughly estimate the availability of a superconducting (SC) linear accelerator (LINAC) as compared to a normal conducting (NC) one. Potentially, SC radio frequency cavities have substantial reserve capability, which allows them to compensate for failed cavities, thus increasing the availability of the overall LINAC. In the initial SC design, there is a klystron and associated equipment (e.g., power supply) for every cavity of an SC LINAC. On the other hand, a single klystron may service eight cavities in the NC LINAC. This study modeled that portion of the Spallation Neutron Source LINAC (between 200 and 1,000 MeV) that is initially proposed for conversion from NC to SC technology. Equipment common to both designs was not evaluated. Tabular fault-tree calculations and computer-event-driven simulation (EDS) computer computations were performed. The estimated gain in availability when using the SC option ranges from 3 to 13% under certain equipment and conditions and spatial separation requirements. The availability of an NC LINAC is estimated to be 83%. Tabular fault-tree calculations and computer EDS modeling gave the same 83% answer to within one-tenth of a percent for the NC case. Tabular fault-tree calculations of the availability of the SC LINAC (where a klystron and associated equipment drive a single cavity) give 97%, whereas EDS computer calculations give 96%, a disagreement of only 1%. This result may be somewhat fortuitous because of limitations of tabular fault-tree calculations. For example, tabular fault-tree calculations can not handle spatial effects (separation distance between failures), equipment network configurations, and some failure combinations. EDS computer modeling of various equipment configurations were examined. When there is a klystron and associated equipment for every cavity and adjacent cavity, failure can be tolerated and the SC availability was estimated to be 96%. SC availability decreased as

  2. Physics design of APT linac with normal conducting rf cavities

    International Nuclear Information System (INIS)

    Nath, S.; Billen, J.H.; Stovall, J.E.; Takeda, Harunori; Young, L.M.

    1996-01-01

    The accelerator based production of tritium calls for a high-power, cw proton linac. Previous designs for such a linac use a radiofrequency quadrupole (RFQ), followed by a drift-tube linac (DTL) to an intermediate energy and a coupled-cavity linc (CCL) to the final energy. The Los Alamos design uses a high-energy (6.7 MeV) RFQ followed by the newly developed coupled-cavity drift-tube linac (CCDTL) and a CCL. This design accommodates external electromagnetic quadrupole lenses which provide a strong uniform focusing lattice from the end of the RFQ to the end of the CCL. The cell lengths in linacs of traditional design are typically graded as a function of particle velocity. By making groups of cells symmetric in both the CCDTL and CCL, the cavity design as well as mechanical design and fabrication is simplified without compromising the performance. At higher energies, there are some advantages of using superconducting rf cavities. Currently, such schemes are under vigorous study. This paper describes the linac design based on normal conducting cavities and presents simulation results

  3. Beam dynamics design of the 211 MeV APT normal conducting linac

    International Nuclear Information System (INIS)

    Young, L.M.; Billen, J.H.; Takeda, H.; Wood, R.L.

    1998-01-01

    This paper describes the normal conducting linac design that is part of the Accelerator for Production of Tritium (APT) project. The new version of PARMILA designed this linac. This linac accepts the beam from the 6.7 MeV radio frequency quadrupole without a separate matching section. At about 10 MeV, it has a smooth transition in the length of period from 8βλ to 9βλ in quadrupole focusing lattice. This adjustment of the period was needed to provide sufficient space for the quadrupole focusing magnets and beam diagnostic equipment. The linac consists of the coupled cavity drift tube linac up to 97 MeV and coupled cavity linac above 97 MeV

  4. Superconducting versus normal conducting cavities

    CERN Document Server

    Podlech, Holger

    2013-01-01

    One of the most important issues of high-power hadron linacs is the choice of technology with respect to superconducting or room-temperature operation. The favour for a specific technology depends on several parameters such as the beam energy, beam current, beam power and duty factor. This contribution gives an overview of the comparison between superconducting and normal conducting cavities. This includes basic radiofrequency (RF) parameters, design criteria, limitations, required RF and plug power as well as case studies.

  5. A SUPER-CONDUCTING LINAC DRIVER FOR THE HFBR.

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, J.; Raparia, D.; Ruggiero, A.G.

    2000-08-21

    This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a driver for the High-Flux Breeder Reactor (HFBR) at Brookhaven National Laboratory (BNL). The Linac operates in Continuous Wave (CW) mode to produce an average 10 MW of beam power. The Linac beam energy is 1.0 GeV. The average proton beam intensity in exit is 10 mA.

  6. Resonator controller for the super-conducting LINAC

    International Nuclear Information System (INIS)

    Joshi, Gopal; Sujo, C.I.; Karande, Jitendra

    2001-01-01

    A resonator controller has been developed at Electronics Division, BARC, to stabilize the amplitude and phase of RF fields in the super-conducting resonators of BARC-TIFR linac. Due to reduced losses these resonators have intrinsic bandwidth of the order of one hertz at 150MHz whereas the vibration induced center frequency changes are of the order of a few hertz. In the control strategy followed the resonator is made the frequency selective part of an oscillator. The phase lock is achieved by dynamically adding a phase shift in the oscillator. In this paper we present the control strategy, implementation details and performance obtained with this controller. (author)

  7. RF system for the super conducting proton linac

    International Nuclear Information System (INIS)

    Touchi, Y.

    2001-01-01

    In this paper, we introduce the several types of RF sources used for proton liner accelerators. Also we discus the undesirable characteristics of super-conducting cavities, and the influence of the large beam loading for an accelerating field. We propose the RF system for the super-conducting proton linear accelerators using the Diacrode or IOT taking these effects into account. (author)

  8. Application of superconductivity to intense proton linacs

    International Nuclear Information System (INIS)

    Heinrichs, H.

    1996-01-01

    Three examples of proposed superconducting linacs for intense particle beams are presented, and in two cases compared to normal conducting counterparts. Advantages and disadvantages of both types are discussed. Suggestions for future developments are presented. Finally a comparison of estimated operational costs of the normal and the superconducting linac for the ESS is given. (R.P.)

  9. A New RF System for the CEBAF Normal Conducting Cavities

    International Nuclear Information System (INIS)

    Curt Hovater; Hai Dong; Alicia Hofler; George Lahti; John Musson; Tomasz Plawski

    2004-01-01

    The CEBAF Accelerator at Jefferson Lab is a 6 GeV five pass electron accelerator consisting of two superconducting linacs joined by independent magnetic transport arcs. CEBAF also has numerous normal conducting cavities for beam conditioning in the injector and for RF extraction to the experimental halls. The RF systems that presently control these cavities are becoming expensive to maintain, therefore a replacement RF control system is now being developed. For the new RF system, cavity field control is maintained digitally using an FPGA which contains the feedback algorithm. The system incorporates digital down conversion, using quadrature under-sampling at an IF frequency of 70 MHz. The VXI bus-crate was chosen as the operating platform because of its excellent RFI/EMI properties and its compatibility with the EPICS control system. The normal conducting cavities operate at both the 1497 MHz accelerating frequency and the sub-harmonic frequency of 499 MHz. To accommodate this, the ne w design will use different receiver-transmitter daughter cards for each frequency. This paper discusses the development of the new RF system and reports on initial results

  10. Normal Conducting RF Cavity for MICE

    International Nuclear Information System (INIS)

    Li, D.; DeMello, A.; Virostek, S.; Zisman, M.; Summers, D.

    2010-01-01

    Normal conducting RF cavities must be used for the cooling section of the international Muon Ionization Cooling Experiment (MICE), currently under construction at Rutherford Appleton Laboratory (RAL) in the UK. Eight 201-MHz cavities are needed for the MICE cooling section; fabrication of the first five cavities is complete. We report the cavity fabrication status including cavity design, fabrication techniques and preliminary low power RF measurements.

  11. Low-charge-state linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Kim, J.W.

    1995-08-01

    A design is being developed for a low-charge-state linac suitable for injecting ATLAS with a low-charge-state, radioactive beam. Initial work indicates that the existing ATLAS interdigital superconducting accelerating structures, together with the superconducting quadrupole transverse focussing element discussed above, provides a basis for a high-performance low-charge-state linac. The initial 2 or 3 MV of such a linac could be based on a normally-conducting, low-frequency RFQ, possibly combined with 24-MHz superconducting interdigital structures. Beam dynamics studies of the whole low-charge-state post-accelerator section were carried out in early FY 1995.

  12. Statistical simulations of machine errors for LINAC4

    CERN Document Server

    Baylac, M.; Froidefond, E.; Sargsyan, E.

    2006-01-01

    LINAC 4 is a normal conducting H- linac proposed at CERN to provide a higher proton flux to the CERN accelerator chain. It should replace the existing LINAC 2 as injector to the Proton Synchrotron Booster and can also operate in the future as the front end of the SPL, a 3.5 GeV Superconductingg Proton Linac. LINAC 4 consists of a Radio-Frequency Quadrupole, a chopper line, a Drift Tube Linac (DTL) and a Cell Coupled DTL all operating at 352 MHz and finally a Side Coupled Linac at 704 MHz. Beam dynamics was studied and optimized performing end-to-end simulations. This paper presents statistical simulations of machine errors which were performed in order to validate the proposed design.

  13. Some aspects of linacs as applied to the ISL benchmark facility

    International Nuclear Information System (INIS)

    Shepard, K.W.

    1992-01-01

    This paper considers several aspects of using linacs in a radioactive beam facility in terms of the Isospin Laboratory (ISL) Benchmark Facility (BMF) plan, described in the 1991 white paper for a possible radioactive-beam laboratory. The intention is not to review comprehensively the application of linacs to an ISL facility, but to compare in outline form several linac options for such a facility. Particular emphasis is given to the use of superconducting rf technology for the secondary beam accelerator. In what follows, first a possible normally-conducting light-ion linac for a primary beam accelerator is briefly outlined. Then the performance and cost of two options for a secondary beam accelerator are compared: a recent design for a normal-conducting cw linac, and an ATLAS-type superconducting linac. Finally, some of the problems which may be encountered at the entrance of a secondary beam linac are discussed

  14. Effect of normal processes on thermal conductivity of germanium ...

    Indian Academy of Sciences (India)

    Abstract. The effect of normal scattering processes is considered to redistribute the phonon momentum in (a) the same phonon branch – KK-S model and (b) between differ- ent phonon branches – KK-H model. Simplified thermal conductivity relations are used to estimate the thermal conductivity of germanium, silicon and ...

  15. The LINAC4 Project at CERN

    CERN Document Server

    Arnaudon, L; Bertone, C; Body, Y; Broere, J; Brunner, O; Buzio, M; Carli, C; Caspers, F; Corso, JP; Coupard, J; Dallocchio, A; Dos Santos, N; Garoby, R; Gerigk, F; Hammouti, L; Hanke, K; Jones, M; Kozsar, I; Lettry, J; Lallement, JB; Lombardi, A; Lopez-Hernandez, LA; Maglioni, C; Mathot, S; Maury, S; Mikulec, B; Nisbet, D; Noels, C; Paoluzzi, M; Puccio, B; Raich, U; Ramberger, S; Rossi, C; Schwerg, N; Scrivens, R; Vandoni, G; Weisz, S; Vollaire, J; Vretenar, M; Zickler, T

    2011-01-01

    As the first step of a long-term programme aiming at an increase in the LHC luminosity, CERN is building a new 160 MeV H¯ linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the PS Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of an H¯ source, a Radio Frequency Quadrupole (RFQ), a chopping line and a sequence of three accelerating structures: a Drift-Tube Linac (DTL), a Cell-Coupled DTL (CCDTL) and a Pi-Mode Structure (PIMS). The civil engineering has been recently completed, and construction of the main accelerator components has started with the support of a network of international collaborations. The low-energy section up to 3 MeV including a 3-m long 352 MHz RFQ entirely built at CERN is in the final construction phase and is being installed on a dedicated test stand. The present schedule foresees beam commissioning of the accelerator in the new tunnel in 2013/14; the moment of connection of the new linac to the CERN accelerator chain will depend on the L...

  16. Imaging of Conductive Hearing Loss With a Normal Tympanic Membrane.

    Science.gov (United States)

    Curtin, Hugh D

    2016-01-01

    This article presents an approach to imaging conductive hearing loss in patients with normal tympanic membranes and discusses entities that should be checked as the radiologist evaluates this potentially complicated issue. Conductive hearing loss in a patient with a normal tympanic membrane is a complicated condition that requires a careful imaging approach. Imaging should focus on otosclerosis, and possible mimics and potential surgical considerations should be evaluated. The radiologist should examine the ossicular chain and the round window and keep in mind that a defect in the superior semicircular canal can disturb the hydraulic integrity of the labyrinth.

  17. Major projects for the use of high power linacs

    International Nuclear Information System (INIS)

    Prome, M.

    1996-01-01

    A review of the major projects for high power linacs is given. The field covers the projects aiming at the transmutation of nuclear waste or the production of tritium, as well as the production of neutrons for hybrid reactors or basic research with neutron sources. The technologies which arc common to all the projects are discussed. Comments are made on the technical difficulties encountered by all the projects, and the special problems of the pulsed linacs are mentioned. Elements for a comparison of normal conducting linacs versus superconducting ones are given. Finally the technical developments being made in various laboratories are reviewed. (author)

  18. Induction linacs

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-07-01

    The principle of linear induction acceleration is described, and examples are given of practical configurations for induction linacs. These examples include the Advanced Technology Accelerator, Long Pulse Induction Linac, Radial Line Accelerator (RADLAC), and Magnetically-Insulated Electron-Focussed Ion Linac. A related concept, the auto accelerator, is described in which the high-current electron-beam technology in the sub-10 MeV region is exploited to produce electron beams at energies perhaps as high as the 100 to 1000 MeV range. Induction linacs for ions are also discussed. The efficiency of induction linear acceleration is analyzed

  19. LINAC4 low energy beam measurements

    CERN Document Server

    Hein, L M; Lallement, J B; Lombardi, A M; Midttun, O; Posocco, P; Scrivens, R

    2012-01-01

    Linac4 is a 160 MeV normal-conducting linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton Linac (Linac2) as linear injector for the CERN accelerators. The low energy part, comprising a 45 keV Low Energy Beam Transport system (LEBT), a 3 MeV Radiofrequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) is being assembled in a dedicated test stand for pre-commissioning with a proton beam. During 2011 extensive measurements were done after the source and after the LEBT with the aim of preparing the RFQ commissioning and validating the simulation tools, indispensable for future source upgrades. The measurements have been thoroughly simulated with a multi-particle code, including 2D magnetic field maps, error studies, steering studies and the generation of beam distribution from measurements. Emittance, acceptance and transmission measurements will be presented and compared to the results of the simulations.

  20. CERN Linac4. The space charge challenge

    Energy Technology Data Exchange (ETDEWEB)

    Hein, Lutz Matthias

    2013-08-06

    In the first phase of the upgrade program of the CERN accelerator complex the proton injector Linac2 will be replaced by a new, normal-conducting H-ion Linac, Linac4, allowing a significant increase of the proton flux intensity along the downstream accelerator complex. In the design of Linac4 three beam transport sections are implemented to match the beam between the different accelerator elements and to model the longitudinal pulse structure. These three beam transport sections, which are the most critical locations in terms of beam quality preservation, are in the focus of this thesis. During the work of this thesis the Low Energy Beam Transport (LEBT), which is required to match the source beam to the radiofrequency quadrupole (RFQ), has been commissioned and its beam dynamics re-constructed. The measurement campaign used to reconstruct the LEBT beam dynamics was performed with the aim to prepare the RFQ commissioning and to maximise the LEBT performance. Downstream of the Linac4 accelerator the beam is transported along a 180 m long transfer line to the Proton Synchrotron Booster (PS-Booster). The transfer line optics was studied, optimised and sections were completely re-designed. The new transfer line optics is characterised by an improved preservation of the beam emittance, higher stability of the optical solution with respect to alignment errors and field jitters of the transfer line magnets and it is matched to each of the PS-Booster injection schemes. In a concluding ''Start-To-End'' simulation based on the measured beam characteristics at the LEBT exit the beam dynamics of the downstream Linac, including the transfer line, was calculated. To minimise particle losses within acceptable emittance preservation the beam optics of the Medium Energy Beam Transport (MEBT) was adapted to the measured beam parameters. This ''Start-To-End'' simulation was performed to identify critical sections of the Linac4 beam dynamics and

  1. Design study of a normal conducting helical snake for AGS

    CERN Document Server

    Takano, Junpei; Okamura, Masahiro; Roser, Thomas; MacKay, William W; Luccio, Alfredo U; Takano, Koji

    2004-01-01

    A new normal conducting snake magnet is being fabricated for the Alternate Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). In the Relativistic Heavy Ion Collider (RHIC) project, a superconducting type helical dipole magnets had been developed and it performed successfully in high-energy polarized proton acceleration. The new AGS helical snake has the same basic magnetic structure but is more complicated. To achieve no beam shift and no beam deflection in one magnetic device, helical pitches and rotating angles were carefully calculated. Compared to a superconducting magnet, a normal warm magnet must have a large cross- sectional area of conductors which make it difficult to design a magnet with large helical pitch. We developed a modified window frame structure to accommodate the large number of conductors. Its three dimensional magnetic field was simulated by using OPERA3D/TOSCA. 3 Refs.

  2. SUPERCONDUCTING LINAC FOR THE SPALLATION NEUTRON SOURCE

    International Nuclear Information System (INIS)

    STOVALL, J.; NATH, S.

    2000-01-01

    The Spallation Neutron Source (SNS) linac is comprised of both normal and superconducting rf (SRF) accelerating structures. The SRF linac accelerates the beam from 186 to 1250 MeV through 117 elliptical, multi-cell niobium cavities. This paper describes the SRF linac architecture, physics design considerations, cavity commissioning, and the expected beam dynamics performance

  3. Alignment and Field Error Tolerance in Linac4

    CERN Document Server

    Bellodi, G; Garcia Tudela, M; Hein, L; Lallement, J B; Lanzone, S; Lombardi, A M; Posocco, P; Sargsyan, E

    2011-01-01

    LINAC4 [1] is a linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton LINAC (LINAC2) as linear injector for the CERN accelerators. The higher output energy (160 MeV) together with charge-exchange injection will allow increasing beam intensity in the following machines. LINAC4 is about 80 m long, normal-conducting, and will be housed in a tunnel 12 m below ground on the CERN Meyrin site. The location has been chosen to allow using LINAC4 as the first stage of acceleration for a Multi-MegaWatt superconducting LINAC (SPL [2]). A 60 m long transfer line brings the beam towards the present LINAC2-to-PS Booster transfer line, which is joined at the position of BHZ20. The new transfer line consists of 17 new quadrupoles, an RF cavity and 4 bending magnets to adjust both the direction and the level for injection into the PS Booster. End-to-end beam dynamics simulations have been carried out in parallel with the codes PATH [3] and TRACEWIN[4]. Following the definition of the layout...

  4. Normal Conducting Separation Dipoles For The Lhc Beam Cleaning Insertions

    CERN Document Server

    Petrov, V; de Rijk, G; Gerard, D; Hans, O; Kalbreier, Willi; Kiselev, O; Protopopov, I V; Pupkov, Yu; Ramberger, S; Ruvinsky, E; Sukhanov, A

    2004-01-01

    In the Large Hadron Collider (LHC), two straight sections, IR3 and IR7, will be dedicated to beam cleaning [1]. These cleaning insertions will be equipped with normal conducting magnets. MBW magnets are dipole magnets used to increase the separation of the two beams. They have a core length of 3.4 m and a gap height of 52 mm and will operate at a magnetic field ranging from 0.09 T to 1.53 T. Limitations on the dimensions and total weight of the magnet resulted in a special design with a common yoke for the two beams. The orbits of the two beams will be separated horizontally by a distance between 194 mm and 224 mm in the gap of the magnet. The magnet was designed in collaboration between CERN and BINP. The report presents the main design issues and results of the pre-series acceptance tests including mechanical, electrical and magnetic field measurements. Index terms - LHC, normal conducting magnet, twin aperture design, separation dipole

  5. Electron linacs

    Energy Technology Data Exchange (ETDEWEB)

    Loew, G A; Schriber, S O [ed.

    1976-11-01

    A study was made of the present status of the thousand or so electron linacs in the world, and future trends in the field. These machines were classified according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for x-ray and electron therapy, and those which may in the future be used for negative pion therapy. Industrial machines discussed include linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a c-w, 1 GeV, 100..mu..A electron linac is raised, and various options using recirculation and stretchers are examined. In this connection, the status of rf superconductivity is summarized. A review is given of linacs for injectors into synchrotrons and e/sup +-/ storage rings, and recent work done to upgrade the only multi-GeV linac, namely SLAC, is described.

  6. Electron linacs

    International Nuclear Information System (INIS)

    Loew, G.A.

    1976-01-01

    To study the present status of the thousand or so electron linacs in the world, and future trends in the field, we have classified these machines according to their use: medical, industrial, and nuclear physics. In the medical category, two types of electron linacs are discussed: the conventional ones which are used for X-ray and electron therapy, and those which may in the future be used for negative pion therapy. The section on industrial machines includes linacs for radiographic and other specialized applications. In the nuclear physics category, the status of conventional low- and medium-energy as well as high duty cycle linacs is reviewed. The question of how one might obtain a C.W., 1 GeV, 100 μA electron linac is raised and various options using recirculation and stretchers are examined. In this connection, the status of RF superconductivity is summarized. Following, there is a review of linacs for injectors into synchrotrons and e +- storage rings. The paper ends with a description of recent work done to upgrade the only multi-GeV linac, namely SLAC. (author)

  7. Superconducting linac

    International Nuclear Information System (INIS)

    Bollinger, L.M.; Shepard, K.W.; Wangler, T.P.

    1978-01-01

    This project has two goals: to design, build, and test a small superconducting linac to serve as an energy booster for heavy ions from an FN tandem electrostatic accelerator, and to investigate various aspects of superconducting rf technology. The main design features of the booster are described, a status report on various components (resonators, rf control system, linac control system, cryostats, buncher) is given, and plans for the near future are outlined. Investigations of superconducting-linac technology concern studies on materials and fabrication techniques, resonator diagnostic techniques, rf-phase control, beam dynamics computer programs, asymmetry in accelerating field, and surface-treatment techniques. The overall layout of the to-be-proposed ATLAS, the Argonne Tandem-Linac Accelerator System, is shown; the ATLAS would use superconducting technology to produce beams of 5 to 25 MeV/A. 6 figures

  8. RF Breakdown in Normal Conducting Single-cell Structures

    CERN Document Server

    Dolgashev, Valery A; Higo, Toshiyasu; Nantista, Christopher D; Tantawi, Sami G

    2005-01-01

    Operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The limit depends on multiple parameters, including input rf power, rf circuit, cavity shape and material. Experimental and theoretical study of the effects of these parameters on the breakdown limit in full scale structures is difficult and costly. We use 11.4 GHz single-cell traveling wave and standing wave accelerating structures for experiments and modeling of rf breakdown behavior. These test structures are designed so that the electromagnetic fields in one cell mimic the fields in prototype multicell structures for the X-band linear collider. Fields elsewhere in the test structures are significantly lower than that of the single cell. The setup uses matched mode converters that launch the circular TM01 mode into short test structures. The test structures are connected to the mode launchers with vacuum rf flanges. This setup allows economic testing of different cell geometries, cell materials an...

  9. The Properties of Normal Conducting Cathodes in FZD Superconducting Gun

    CERN Document Server

    Xiang, R; Buettig, H; Janssen, D; Justus, M; Lehnert, U; Michel, P; Murcek, P; Schamlott, A; Schneider, Ch; Schurig, R; Staufenbiel, F; Teichert, J

    2009-01-01

    The superconducting radio frequency photoinjector (SRF photoinjector) is one of the latest applications of SC technology in the accelerator field. Since superconducting cathodes with high QE are not available up to now, normal conducting cathode material is the main choice for the SRF photoinjectors. However, the compatibility between the cathode and the cavity is one of the challenges for this concept. The SRF gun with Cs2Te cathode has been successfully operated under the collaboration of BESSY, DESY, FZD, and MBI. In this paper, some experience gained in the gun commissioning will be concluded. The results of the properties of Cs2Te photocathode in the cavity will be presented, such as the Q.E., the life time, the dark current and the thermal emittance.

  10. Normal Conducting Separation Dipoles for the LHC Beam Cleaning Insertions

    CERN Document Server

    Bidon, S; Hans, O; Kalbreier, Willi; Kiselev, O; Petrov, V; Protopopov, I V; Pupkov, Yu A; Ramberger, S; de Rijk, G; Ruvinsky, E; Sukhanov, A

    2004-01-01

    In the Large Hadron Collider (LHC), two straight sections, IR3 and IR7, will be dedicated to beam cleaning. These cleaning insertions will be equipped with normal conducting magnets. MBW magnets are dipole magnets used to increase the separation of the two beams. They have a core length of 3.4 m and a gap height of 52 mm and will operate at a magnetic field ranging from 0.09 T to 1.53 T. Limitations on the dimensions and total weight of the magnet resulted in a special design with a common yoke for the two beams. The orbits of the two beams will be separated horizontally by a distance between 194 mm and 224 mm in the gap of the magnet. The magnet was designed in collaboration between CERN and BINP. The report presents the main design issues and results of the pre-series acceptance tests including mechanical, electrical and magnetic field measurements.

  11. Normal Conducting Deflecting Cavity Development at the Cockcroft Institute

    CERN Document Server

    Burt, G; Dexter, A C; Woolley, B; Jones, R M; Grudiev, A; Dolgashev, V; Wheelhouse, A; Mackenzie, J; McIntosh, P A; Hill, C; Goudket, P; Buckley, S; Lingwood, C

    2013-01-01

    Two normal conducting deflecting structures are currently being developed at the Cockcroft Institute, one as a crab cavity for CERN linear collider CLIC and one for bunch slice diagnostics on low energy electron beams for Electron Beam Test Facility EBTF at Daresbury. Each has its own challenges that need overcome. For CLIC the phase and amplitude tolerances are very stringent and hence beamloading effects and wakefields must be minimised. Significant work has been undertook to understand the effect of the couplers on beamloading and the effect of the couplers on the wakefields. For EBTF the difficulty is avoiding the large beam offset caused by the cavities internal deflecting voltage at the low beam energy. Prototypes for both cavities have been manufactured and results will be presented.

  12. Coherent tunnelling conductance in normal-metal/d-wave superconductor/normal-metal double tunnel junctions

    International Nuclear Information System (INIS)

    Dong, Z C; Zheng, Z M; Xing, D Y

    2004-01-01

    Taking simultaneously into account the electron-injected current from one normal-metal (N) electrode and the hole-injected current from the other N electrode, we study the coherent tunnelling conductance and quantum interference effects in N/d-wave superconductor (S)/N double tunnel junctions. It is found that oscillations of all quasiparticle transport coefficients and the conductance spectrum with quasiparticle energy and thickness of the d-wave S depend to a great extent on the crystal orientation of the d-wave S. The zero-bias conductance peak is gradually lowered with increasing barrier strength and/or temperature, its magnitude exhibiting damped oscillatory behaviour with thickness of S

  13. Development of the High Energy Linac Systems

    International Nuclear Information System (INIS)

    Cho, Yong Sub; Kwon, Hyeok Jung; Kim, Han Sung; Chung, Byung Chul; Jang, Ji Ho; Gao, Changgi; Li, Yingmin; Sun, An; Tang, Yazhe; Zhang, Lipoing; Hwang, Yong Seok

    2008-05-01

    The main purpose of this project is studying the extension plan of the proton engineering frontier project (PEFP) 100-MeV Linac. It includes three categories. One is studying operation plan of the PEFP linac and its extended accelerators, and developing a distribution system of 100-MeV proton beams with a laser striping. Other is designing superconducting RF (SRF) modules and fabricating and testing a copper cavity model. The other is designing a rapid cycling synchrotron (RCS). The operation scheme of the PEFP linac is related to the optimization in the operation of the 100-MeV linac, 200-MeV SRF, and RCS. We studied several operational method to increase the validity of the accelerators. The beam distribution system has two roles. One is supplying proton beams of 100 MeV to the user group. The laser stripping of the negative hydrogen atoms is used in this case. The other beams are directed to the next high energy accelerators. This study contributes to increase the availability of the proton beams. The SRF is one of candidates to extend the PEFP linac system. Since the accelerating gradient of the SRF is much higher than the normal conducting accelerator, a lot of institutes over the world are developing the SRF structure. Main purposes are designing an SRF module, fabricating and testing an copper model which has similar material properties as Nb of the usual SRF cavity material. The RCS is a synchrotron whose injector is the PEFP 100-MeV linac. Main purposes are determining the lattice structure, studying the fast and slow extraction system, simulating beam behavior in the designed synchrotron. The RCS will be used as the spallation neutron source and tools in the basic and applied science including medical application

  14. Avoiding vacuum arcs in high gradient normal conducting RF structures

    CERN Document Server

    Sjøbæk, Kyrre Ness; Adli, Erik; Grudiev, Alexej; Wuensch, Walter

    In order to build the Compact LInear Collider (CLIC), accelerating structures reaching extremely high accelerating gradients are needed. Such structures have been built and tested using normal-conducting copper, powered by X-band RF power and reaching gradients of 100 MV/m and above. One phenomenon that must be avoided in order to reliably reach such gradients, is vacuum arcs or “breakdowns”. This can be accomplished by carefully designing the structure geometry such that high surface fields and large local power flows are avoided. The research presented in this thesis presents a method for optimizing the geometry of accelerating structures so that these breakdowns are made less likely, allowing the structure to operate reliably at high gradients. This was done primarily based on a phenomenological scaling model, which predicted the maximum gradient as a function of the break down rate, pulse length, and field distribution in the structure. The model is written in such a way that it allows direct comparis...

  15. RF Breakdown in Normal Conducting Single-Cell Structures

    International Nuclear Information System (INIS)

    Dolgashev, V.A.; Nantista, C.D.; Tantawi, S.G.; Higashi, Y.; Higo, T.

    2006-01-01

    Operating accelerating gradient in normal conducting accelerating structures is often limited by rf breakdown. The limit depends on multiple parameters, including input rf power, rf circuit, cavity shape and material. Experimental and theoretical study of the effects of these parameters on the breakdown limit in full scale structures is difficult and costly. We use 11.4 GHz single-cell traveling wave and standing wave accelerating structures for experiments and modeling of rf breakdown behavior. These test structures are designed so that the electromagnetic fields in one cell mimic the fields in prototype multicell structures for the X-band linear collider. Fields elsewhere in the test structures are significantly lower than that of the single cell. The setup uses matched mode converters that launch the circular TM 01 mode into short test structures. The test structures are connected to the mode launchers with vacuum rf flanges. This setup allows economic testing of different cell geometries, cell materials and preparation techniques with short turn-around time. Simple 2D geometry of the test structures simplifies modeling of the breakdown currents and their thermal effects

  16. Status and plans for Linac4 installation and commissioning

    CERN Document Server

    Vretenar, M; Arnaudon, L; Baudrenghien, P; Bellodi, G; Broere, J; Brunner, O; Comblin, J F; Coupard, J; Dimov, V A; Fuchs, J F; Funken, A; Gerigk, F; Granemann Souza, E; Hanke, K; Hansen, J; Yarmohammadi Satri, M; Kozsar, I; Lallement, J B; Lenardon, F; Lettry, J; Lombardi, A M; Maglioni, C; Midtun, O; Mikulec, B; Nisbet, D; Paoluzzi, M; Raich, U; Ramberger, S; Roncarolo, F; Rossi, C; Sanchez Alvarez, J L; Scrivens, R; Tan, J; Valerio-Lizarraga, C A; Vollaire, J; Wegner, R; Weisz, S; Zocca, F

    2014-01-01

    Linac4 is a normal conducting 160 MeV Hˉ linear accelerator presently being installed and progressively commissioned at CERN. It will replace the ageing 50 MeV Linac2 as injector of the PS Booster (PSB), increasing at the same time its brightness by a factor of two thanks to the higher injection energy. This will be the first step of a program to increase the beam brightness in the LHC injectors for the needs of the High-Luminosity LHC project. After a series of beam measurements on a dedicated test stand the 3 MeV Linac4 front-end, including ion source, RFQ and a beam chopping line, has been recommissioned at its final position in the Linac4 tunnel. Commissioning of the following section, the Drift Tube Linac, is starting. Beam commissioning will take place in steps of increasing energy, to reach the final 160 MeV in 2015. An extended beam measurement phase including testing of stripping equipment for the PSB and a year-long test run to assess and improve Linac4 reliability will take place in 2016, prior to...

  17. SNS superconducting linac

    International Nuclear Information System (INIS)

    Sundelin, Ronald M.

    2001-01-01

    The Spallation Neutron Source (SNS) decided in early 2000 to use superconducting RF (SRF) in the linac at energies above 185 MeV. Since the SNS duty cycle is 6%, the SRF and normal conducting approaches have capital costs which are about the same, but operating costs and future upgradability are improved by using SRF. The current status of cavity and cryomodule development and procurement, including the basis for decisions made, is discussed. The current plan includes use of 805 MHz, 6-cell cavities with geometrical betas of 0.61 and 0.81. There are 33 medium beta and 60 high beta cavities in 11 and 15 cryomodules, respectively. Each cavity (except the 93rd) is powered by a 550 kW pulsed klystron. Issues addressed include choice of peak surface gradient, optimization of cavity shape, selection of a scaled KEK input power coupler, selection of scaled TESLA higher mode couplers, and control of the effects of higher order modes on the beam. (author)

  18. CERN Linac4 - The Space Charge Challenge Design and Commission

    CERN Document Server

    Hein, Lutz Matthias; Holzer, Bernhard

    In the first phase of the upgrade program of the CERN accelerator complex the proton injector Linac2 will be replaced by a new, normal-conducting $H^-$ ion Linac, Linac4, allowing a significant increase of the proton flux intensity along the downstream accelerator complex. In the design of Linac4 three beam transport sections are implemented to match the beam between the different accelerator elements and to model the longitudinal pulse structure. These three beam transport sections, which are the most critical locations in terms of beam quality preservation, are in the focus of this thesis. During the work of this thesis the low energy beam transport (LEBT), which is required to match the source beam to the radiofrequency quadrupole (RFQ), has been commissioned and its beam dynamics re-constructed. The measurement campaign used to re-construct the LEBT beam dynamics was performed with the aim to prepare the RFQ commissioning and to maximise the LEBT performance. Downstream of the Linac4 accelerator the beam...

  19. Design of LINAC4, A New Injector for the CERN Booster

    CERN Document Server

    Garoby, R; Lombardi, A M; Rossi, C; Vretenar, M; Gerigk, F

    2004-01-01

    A new H- linac (Linac4) is presently under study at CERN. This accelerator, based on normal conducting structures at 352 and 704 MHz, will provide a 30 mA 160 MeV H- beam to the CERN PS Booster (PSB), thus overcoming the present space-charge bottleneck at injection with a 50 MeV proton beam. Linac4 is conceived as the first stage of a future 2.2 GeV superconducting linac (SPL) and it is therefore designed for a higher duty cycle than necessary for the PSB. This paper discusses the design choices, presents the layout of the facility and illustrates the advantages for the LHC and other CERN users. The R&D and construction strategy, which mainly relies upon international collaborations, is also presented.

  20. Development of a commissioning plan for the APT linac

    International Nuclear Information System (INIS)

    Funk, L.W.; Crandall, K.R.; Gilpatrick, J.D.; Gray, E.R.; Regan, A.H.; Rohlev, A.; Rybarcyk, L.J.; Wangler, T.P.

    1998-01-01

    The Accelerator Production of Tritium (APT) facility is based on a linac which incorporates both normal-conducting and superconducting RF technology and accelerates a 100-mA cw proton beam to an energy of 1,030 MeV or higher, depending on the desired production rate. Commissioning plans to achieve full power operation with minimum beam-induced activation of components have been evolving. This paper presents the main issues and the basic approaches that are now being discussed

  1. The Superconducting Super Collider (SSC) linac

    International Nuclear Information System (INIS)

    Watson, J.M.

    1990-09-01

    The preliminary design of the 600 MeV H - linac for the Superconducting Super Collider injector is described. The linac must provide a 25 mA beam during 7--35 μs macropulses at Hz within injection bursts. Normalized transverse emittances of less than 0.5 π mm-mrad (rms) are required for injection into the Low Energy Booster synchrotron. Cost, ease of commissioning, and operational reliability are important considerations. The linac will consists of an H - source with electrostatic LEBT, 2.5 MeV radiofrequency quadrupole accelerator, a 70 MeV drift-tube linac, and 530 MeV and the side-coupled linac operates at 1284 MHz. A modest total length of 150 m results from the tradeoff between cost optimization and reliability. The expected performance from beam dynamics simulations and the status of the project are described. 11 refs., 1 fig., 6 tabs

  2. Assessment of Alternative RF Linac Structures for APT

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-03-26

    The APT program has been examining both normal and superconducting variants of the APT linac for the past two years. A decision on which of the two will be the selected technology will depend upon several considerations including the results of ongoing feasibility experiments, the performance and overall attractiveness of each of the design concepts, and an assessment of the system-level features of both alternatives. The primary objective of the Assessment of Alternative RF Linac Structures for APT study reported herein was to assess and compare, at the system-level, the performance, capital and life cycle costs, reliability/availability/maintainability (RAM) and manufacturing schedules of APT RF linear accelerators based upon both superconducting and normal conducting technologies. A secondary objective was to perform trade studies to explore opportunities for system optimization, technology substitution and alternative growth pathways and to identify sensitivities to design uncertainties.

  3. Assessment of Alternative RF Linac Structures for APT

    International Nuclear Information System (INIS)

    None

    1997-01-01

    The APT program has been examining both normal and superconducting variants of the APT linac for the past two years. A decision on which of the two will be the selected technology will depend upon several considerations including the results of ongoing feasibility experiments, the performance and overall attractiveness of each of the design concepts, and an assessment of the system-level features of both alternatives. The primary objective of the Assessment of Alternative RF Linac Structures for APT study reported herein was to assess and compare, at the system-level, the performance, capital and life cycle costs, reliability/availability/maintainability (RAM) and manufacturing schedules of APT RF linear accelerators based upon both superconducting and normal conducting technologies. A secondary objective was to perform trade studies to explore opportunities for system optimization, technology substitution and alternative growth pathways and to identify sensitivities to design uncertainties

  4. On the possibility of a normal conducting photo-injector for Tesla

    International Nuclear Information System (INIS)

    Travier, C.

    1992-12-01

    The possibility of using a normal conducting photo-injector for the TESLA linear collider is investigated. It is shown that the 8 nC,3 ps bunch can be produced with a normalized emittance less than 100 Π mm mrad. The generation of the train depends on the feasibility of the laser which has to be looked at more carefully

  5. SRF LINAC for future extension of the PEFP

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Sung; Kwon, Hyeok Jung; Seol, Kyoung Tae; Jang, Ji Ho; Cho, Yong Sub [Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-04-15

    A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

  6. SRF LINAC for future extension of the PEFP

    International Nuclear Information System (INIS)

    Kim, Han Sung; Kwon, Hyeok Jung; Seol, Kyoung Tae; Jang, Ji Ho; Cho, Yong Sub

    2014-01-01

    A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

  7. Commissioning of the 112 MHz SRF Gun and 500 MHz bunching cavities for the CeC PoP Linac

    Energy Technology Data Exchange (ETDEWEB)

    Belomestnykh, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Brutus, J. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); McIntosh, P. [Science and Technology Facilities Council (STFC), Daresbury (United Kingdom). Daresbury Lab.; Moss, A. [Science and Technology Facilities Council (STFC), Daresbury (United Kingdom). Daresbury Lab.; Narayan, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Orfin, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pinayev, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rao, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Skaritka, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tuozzolo, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wang, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wheelhouse, A. [Science and Technology Facilities Council (STFC), Daresbury (United Kingdom). Daresbury Lab.; Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xiao, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xin, T. [Stony Brook Univ., NY (United States); Xu, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zaltsman, A. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    The Coherent electron Cooling Proof-of-Principle (CeC PoP) experiment at BNL includes a short electron linac. During Phase 1, a 112 MHz superconducting RF photo-emission gun and two 500 MHz normal conducting bunching cavities were installed and are under commissioning. The paper describes the Phase1 linac layout and presents commissioning results for the cavities and associated RF, cryogenic and other sub-systems

  8. The KAERI 10 MeV Electron Linac - Description and Operational Manual

    International Nuclear Information System (INIS)

    Lee, Byung Cheol; Park, Seong Hee; Jung, Young Uk; Han, Young Hwan; Kang, Hee Young

    2005-06-01

    The objective of this technical report is to guide the right operation and maintenance of the KAERI electron linac system. The KAERI electron linac system consists of 2 MeV injector based on 176 MHz Normal conducting RF (Radio Frequency)cavity and 10 MeV main accelerator based on 352 MHz Superconducting RF cavity, electron beamlines (injection and extraction). Since a electron accelerator generates hazard radiation, this system is located at the shielded room in basement and we can operate the system using the remote control system. It includes the description and the operational manual as well as the detailed technical direction for trouble shooting

  9. The KAERI 10 MeV Electron Linac - Description and Operational Manual

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Cheol; Park, Seong Hee; Jung, Young Uk; Han, Young Hwan; Kang, Hee Young

    2005-06-15

    The objective of this technical report is to guide the right operation and maintenance of the KAERI electron linac system. The KAERI electron linac system consists of 2 MeV injector based on 176 MHz Normal conducting RF (Radio Frequency)cavity and 10 MeV main accelerator based on 352 MHz Superconducting RF cavity, electron beamlines (injection and extraction). Since a electron accelerator generates hazard radiation, this system is located at the shielded room in basement and we can operate the system using the remote control system. It includes the description and the operational manual as well as the detailed technical direction for trouble shooting.

  10. Linac4 Low Energy Beam Measurements with Negative Hydrogen

    CERN Document Server

    Scrivens, R; Crettiez, O; Dimov, V; Gerard, D; Granemann Souza, E; Guida, R; Hansen, J; Lallement, J B; Lettry, J; Lombardi, A; Midttun, O; Pasquino, C; Raich, U; Riffaud, B; Roncarolo, F; Valerio-Lizarraga, C A; Wallner, J; Yarmohammadi Satri, M; Zickler, T

    2014-01-01

    Linac4, a 160 MeV normal-conducting H- linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H- beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

  11. Linac4 low energy beam measurements with negative hydrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Scrivens, R., E-mail: richard.scrivens@cern.ch; Bellodi, G.; Crettiez, O.; Dimov, V.; Gerard, D.; Granemann Souza, E.; Guida, R.; Hansen, J.; Lallement, J.-B.; Lettry, J.; Lombardi, A.; Midttun, Ø.; Pasquino, C.; Raich, U.; Riffaud, B.; Roncarolo, F.; Valerio-Lizarraga, C. A.; Wallner, J.; Yarmohammadi Satri, M.; Zickler, T. [CERN, 1211 Geneva 23 (Switzerland)

    2014-02-15

    Linac4, a 160 MeV normal-conducting H{sup −} linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ (Radiofrequency Quadrupole) has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H{sup −} beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

  12. Conductance of graphene based normal-superconductor junction with double magnetic barriers

    Science.gov (United States)

    Abdollahipour, B.; Mohebalipour, A.; Maleki, M. A.

    2018-05-01

    We study conductance of a graphene based normal metal-superconductor junction with two magnetic barriers. The magnetic barriers are induced via two applied magnetic fields with the same magnitudes and opposite directions accompanied by an applied electrostatic potential. We solve Dirac-Bogoliubov-De-Gennes (DBdG) equation to calculate conductance of the junction. We find that applying the magnetic field leads to suppression of the Andreev reflection and conductance for all energies. On the other hand, we observe a crossover from oscillatory to tunneling behavior of the conductance as a function of the applied potential by increasing the magnetic field.

  13. Linac 1, inner structure

    CERN Multimedia

    1968-01-01

    This photo shows the inner structure of Linac 1. As injector to the PS, and later to the Booster, Linac 1 accelerated protons to 50 MeV, but it has also accelerated heavier ions. Fitted with a 520 keV RFQ pre-injector (instead of the original Cockcroft-Walton generator), it delivered protons and heavy ions to LEAR, from 1982 to 1992. After 33 years of faithful service, Linac 1 was dismantled in 1992 to make room for Linac 3 (Pb ions).

  14. Construction of SPring-8 LINAC

    International Nuclear Information System (INIS)

    Yokomizo, Hideaki; Yoshikawa, Hiroshi; Suzuki, Shinsuke; Yanagida, Ken-ichi; Mizuno, Akihiko; Hori, Toshihiko; Tamezane, Kenji; Kodera, Masahiko; Sakaki, Hironao; Mashiko, Katsuo

    1993-01-01

    Construction of the linac building has been started in February 1993. The components of the linac are under manufacturing. The preinjector of linac was already constructed and temporarily installed in Tokai Establishment in order to test the beam quality. (author)

  15. Protection of Hardware: Powering Systems (Power Converter, Normal Conducting, and Superconducting Magnets)

    Energy Technology Data Exchange (ETDEWEB)

    Pfeffer, H. [Fermilab; Flora, B. [Fermilab; Wolff, D. [Fermilab

    2016-01-01

    Along with the protection of magnets and power converters, we have added a section on personnel protection because this is our highest priority in the design and operation of power systems. Thus, our topics are the protection of people, power converters, and magnet loads (protected from the powering equipment), including normal conducting magnets and superconducting magnets.

  16. Behavior of conduct disordered children in interaction with each other and with normal peers

    NARCIS (Netherlands)

    MATTHYS, W; VANLOO, P; PACHEN, [No Value; de Vries, Han; VANHOOFF, JARAM; VANENGELAND, H

    1995-01-01

    This study investigated the behavior of children with conduct disorder or oppositional defiant disorder (CD/ODD) in interaction with each other and with normal control (NC) children in a semi-standardized setting over a period of 25 minutes. This short time turned out to be sufficient to demonstrate

  17. BNCT with linac, feasibility study

    International Nuclear Information System (INIS)

    Alfuraih, A.; Ma, A.; Spyrou, N.M.; Awotwi-Pratt, Joseph

    2006-01-01

    High energy photon beams from Medical Linear Accelerators (linacs) which are used in radiotherapy produce undesirable neutrons, beside the clinically useful electron and photon beams. Neutrons are produced from the photonuclear reaction (γ,n) of high energy photons with high Z-materials which compose the accelerator head. In this paper the possible use of these undesirable neutrons for BNCT is investigated, making use of high energy linacs already installed in hospitals, primarily for high energy electron and photon therapy and applying them in the context of BNCT. The photoneutron components emitted by the accelerator is the source for Monte Carlo simulations of the interactions that take place within the head of a voxel-based phantom. The neutron flux across the phantom head is calculated using different moderator arrangements and different techniques in the aim of increasing the thermal neutron flux at the targeted site. Also, we shall test different configurations of the linac head to maximize the exposure of high-Z materials to the photon beam, including the removal of the flattening filter, so as to boost the photoneutron production in the linac head. Experimental work will be conducted in hospitals to validate the Monte Carlo simulations. To make use of linacs for BNCT will be advantageous in the sense that the setting in a hospital department is much more acceptable by the public than a reactor installation. This will mean less complications regarding patient positioning and movement with respect to the beams, additional patient transportation and management will be more cost effective. (author)

  18. Normal processes of phonon-phonon scattering and thermal conductivity of germanium crystals with isotopic disorder

    CERN Document Server

    Kuleev, I G

    2001-01-01

    The effect of normal processes of the phonon-phonon scattering on the thermal conductivity of the germanium crystals with various isotopic disorder degrees is considered. The phonon pulse redistribution in the normal scattering processes both inside each oscillatory branch (the Simons mechanism) and between various phonon oscillatory branches (the Herring mechanism) is accounted for. The contributions of the longitudinal and cross-sectional phonons drift motion into the thermal conductivity are analyzed. It is shown that the pulse redistribution in the Herring relaxation mechanism leads to essential suppression of the longitudinal phonons drift motion in the isotopically pure germanium crystals. The calculations results of thermal conductivity for the Herring relaxation mechanism agree well with experimental data on the germanium crystals with various isotopic disorder degrees

  19. Workshop: Linac90

    Energy Technology Data Exchange (ETDEWEB)

    Van Dyck, Olin

    1990-12-15

    In 1960 the first linear accelerator (linac) conference was organized at Brookhaven by John Blewett. In the few years following, linear accelerator energies jumped from 50 MeV (at Brookhaven and CERN) to 2 GeV at Stanford. With the realization that, at least for electrons, circular accelerators have reached their practical limits, linacs are once more in the spotlight.

  20. Magnet innovations for linacs

    International Nuclear Information System (INIS)

    Halbach, K.

    1986-01-01

    It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results of past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs are presented

  1. Linac pre-injector

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    New accelerating column of the linac pre-injector, supporting frame and pumping system. This new system uses two mercury diffusion pumps (in the centre) and forms part of the modifications intended to increase the intensity of the linac. View taken during assembly in the workshop.

  2. Magnet innovations for linacs

    International Nuclear Information System (INIS)

    Halbach, K.

    1986-06-01

    It is possible to produce large magnetic fields at the aperture of permanent magnet quadrupoles, even when the magnetic aperture is very small. That, combined with their compactness, makes permanent magnet quadrupoles very powerful components of small aperture linacs. Results will be presented about past and present work on both fixed and variable strength permanent magnets suitable for use in and around linacs

  3. Workshop: Linac90

    International Nuclear Information System (INIS)

    Van Dyck, Olin

    1990-01-01

    In 1960 the first linear accelerator (linac) conference was organized at Brookhaven by John Blewett. In the few years following, linear accelerator energies jumped from 50 MeV (at Brookhaven and CERN) to 2 GeV at Stanford. With the realization that, at least for electrons, circular accelerators have reached their practical limits, linacs are once more in the spotlight

  4. Zero-bias conductance quantization in a normal / superconducting junction of nano wire

    International Nuclear Information System (INIS)

    Asano, Yasuhiro; Tanaka, Yukio

    2012-01-01

    We discuss a strong relationship between Majorana fermions and odd-frequency Cooper pairs which appear at a disordered normal nano wire attached to a topologically nontrivial superconducting one. The zero-bias differential conductance in a normal / superconducting nano wire junctions is quantized at 2e 2 /h irrespective of degree of disorder, length of disordered segment, and random realization of disordered potential. Such behaviors are exactly the same as those in the anomalous proximity effect of p x -wave spin-triplet superconductors. We show that odd-frequency Cooper pairs assist the unusual transport properties.

  5. Design of a 120 MeV $H^{-}$ Linac for CERN High-Intensity Applications

    CERN Document Server

    Gerigk, F

    2002-01-01

    The SPL (Superconducting Proton Linac) study at CERN foresees the construction of a 2.2 GeV linac as a high beam-power driver for applications such as a second-generation radioactive ion beam facility or a neutrino superbeam. At the same time such a high-performance injector would both modernize and improve the LHC injection chain. The 120 MeV normal-conducting section of the SPL could be used directly in a preliminary stage for H- charge-exchange injection into the PS Booster. This would increase the proton flux to the CERN experiments while also improving the quality and reliability of the beams for the LHC. The 120 MeV linac consists of a front-end, a conventional Drift Tube Linac (DTL) to 40 MeV and a Cell Coupled Drift Tube Linac (CCDTL) to the full energy. All the RF structures will operate at 352 MHz, using klystrons and RF equipment recovered from the LEP collider. This paper concentrates on the design of the 3 to 120 MeV section. It introduces the design criteria for high-stability beam optics and th...

  6. Binaural Hearing Ability With Bilateral Bone Conduction Stimulation in Subjects With Normal Hearing: Implications for Bone Conduction Hearing Aids.

    Science.gov (United States)

    Zeitooni, Mehrnaz; Mäki-Torkko, Elina; Stenfelt, Stefan

    The purpose of this study is to evaluate binaural hearing ability in adults with normal hearing when bone conduction (BC) stimulation is bilaterally applied at the bone conduction hearing aid (BCHA) implant position as well as at the audiometric position on the mastoid. The results with BC stimulation are compared with bilateral air conduction (AC) stimulation through earphones. Binaural hearing ability is investigated with tests of spatial release from masking and binaural intelligibility level difference using sentence material, binaural masking level difference with tonal chirp stimulation, and precedence effect using noise stimulus. In all tests, results with bilateral BC stimulation at the BCHA position illustrate an ability to extract binaural cues similar to BC stimulation at the mastoid position. The binaural benefit is overall greater with AC stimulation than BC stimulation at both positions. The binaural benefit for BC stimulation at the mastoid and BCHA position is approximately half in terms of decibels compared with AC stimulation in the speech based tests (spatial release from masking and binaural intelligibility level difference). For binaural masking level difference, the binaural benefit for the two BC positions with chirp signal phase inversion is approximately twice the benefit with inverted phase of the noise. The precedence effect results with BC stimulation at the mastoid and BCHA position are similar for low frequency noise stimulation but differ with high-frequency noise stimulation. The results confirm that binaural hearing processing with bilateral BC stimulation at the mastoid position is also present at the BCHA implant position. This indicates the ability for binaural hearing in patients with good cochlear function when using bilateral BCHAs.

  7. Tunneling Conductance in Ferromagnetic Metal/Normal Metal/Spin-Singlet -Wave Ferromagnetic Superconductor Junctions

    Directory of Open Access Journals (Sweden)

    Hamidreza Emamipour

    2013-01-01

    Full Text Available In the framework of scattering theory, we study the tunneling conductance in a system including two junctions, ferromagnetic metal/normal metal/ferromagnetic superconductor, where ferromagnetic superconductor is in spin-singlet -wave pairing state. The non-magnetic normal metal is placed in the intermediate layer with the thickness ( which varies from 1 nm to 10000 nm. The interesting result which we have found is the existence of oscillations in conductance curves. The period of oscillations is independent of FS and FN exchange field while it depends on . The obtained results can serve as a useful tool to determine the kind of pairing symmetry in ferromagnetic superconductors.

  8. Experimental Modeling of VHTR Plenum Flows during Normal Operation and Pressurized Conduction Cooldown

    Energy Technology Data Exchange (ETDEWEB)

    Glenn E McCreery; Keith G Condie

    2006-09-01

    The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. The present document addresses experimental modeling of flow and thermal mixing phenomena of importance during normal or reduced power operation and during a loss of forced reactor cooling (pressurized conduction cooldown) scenario. The objectives of the experiments are, 1), provide benchmark data for assessment and improvement of codes proposed for NGNP designs and safety studies, and, 2), obtain a better understanding of related phenomena, behavior and needs. Physical models of VHTR vessel upper and lower plenums which use various working fluids to scale phenomena of interest are described. The models may be used to both simulate natural convection conditions during pressurized conduction cooldown and turbulent lower plenum flow during normal or reduced power operation.

  9. TOP LINAC design; Progetto del TOP LINAC

    Energy Technology Data Exchange (ETDEWEB)

    Picardi, L; Ronsivalle, C; Vignati, A [ENEA, Centro Ricerche Frascati, Rome (Italy). Dip. Innovazione

    1997-11-01

    The report describes a linear accelerator for protons named TOP LINAC designed for the TOP (Terapia Oncologica con Protoni, Oncological Protontherapy) project launched by the Italian National Institute of Health (Istituto Superiore di Sanita`, ISS) to explore in collaboration with the biggest Oncological Hospital in Rome (Istituto Regina Elena, IRE) the potentialities of the therapy with accelerated protons and establish guide lines for the application of this new type of radiotherapy in comparison with the more traditional electron and x-rays radiotherapy. The concept of a compact accelerator for protontherapy applications bore within the Italian Hadrontherapy Collaboration (TERA Collaboration) with the aim to diffuse the protontherapy on the National territory. The ISS program plans to use the TOP linac proton beam also for production of PET (Positron Emission Tomography) radioisotopes and radiobiology studies. Official agreements are in course between ISS and ENEA which provides its experience in the industrial and medical accelerators for the design and the construction of the TOP linac. The accelerator that will be the first 3 GHz proton linac in the world, will be composed of a 428.3 MHz 7 Me V RFQ + DTL injector followed by a 7-65 Me V section of a 3 GHz SCDTL structure and a 65 - 200 Me V variable energy SCL 3 GHz structure. In particular the SCDTL section uses a highly innovative accelerating structure patented by ENEA. In this report the clinical and physical requests are discussed and a preliminary design of the whole machine is given.

  10. DESCRIPTION OF BRAINSTEM AUDITORY EVOKED RESPONSES (AIR AND BONE CONDUCTION IN CHILDREN WITH NORMAL HEARING

    Directory of Open Access Journals (Sweden)

    A. V. Pashkov

    2014-01-01

    Full Text Available Diagnosis of hearing level in small children with conductive hearing loss associated with congenital craniofacial abnormalities, particularly with agenesis of external ear and external auditory meatus is a pressing issue. Conventional methods of assessing hearing in the first years of life, i. e. registration of brainstem auditory evoked responses to acoustic stimuli in the event of air conduction, does not give an indication of the auditory analyzer’s condition due to potential conductive hearing loss in these patients. This study was aimed at assessing potential of diagnosing the auditory analyzer’s function with registering brainstem auditory evoked responses (BAERs to acoustic stimuli transmitted by means of a bone vibrator. The study involved 17 children aged 3–10 years with normal hearing. We compared parameters of registering brainstem auditory evoked responses (peak V depending on the type of stimulus transmission (air/bone in children with normal hearing. The data on thresholds of the BAERs registered to acoustic stimuli in the event of air and bone conduction obtained in this study are comparable; hearing thresholds in the event of acoustic stimulation by means of a bone vibrator correlates with the results of the BAERs registered to the stimuli transmitted by means of air conduction earphones (r = 0.9. High correlation of thresholds of BAERs to the stimuli transmitted by means of a bone vibrator with thresholds of BAERs registered when air conduction earphones were used helps to assess auditory analyzer’s condition in patients with any form of conductive hearing loss.  

  11. Compendium of Scientific Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Clendenin, James E

    2003-05-16

    The International Committee supported the proposal of the Chairman of the XVIII International Linac Conference to issue a new Compendium of linear accelerators. The last one was published in 1976. The Local Organizing Committee of Linac96 decided to set up a sub-committee for this purpose. Contrary to the catalogues of the High Energy Accelerators which compile accelerators with energies above 1 GeV, we have not defined a specific limit in energy. Microtrons and cyclotrons are not in this compendium. Also data from thousands of medical and industrial linacs has not been collected. Therefore, only scientific linacs are listed in the present compendium. Each linac found in this research and involved in a physics context was considered. It could be used, for example, either as an injector for high energy accelerators, or in nuclear physics, materials physics, free electron lasers or synchrotron light machines. Linear accelerators are developed in three continents only: America, Asia, and Europe. This geographical distribution is kept as a basis. The compendium contains the parameters and status of scientific linacs. Most of these linacs are operational. However, many facilities under construction or design studies are also included. A special mention has been made at the end for the studies of future linear colliders.

  12. Machine Imperfection Studies of the RAON Superconducting Linac

    Science.gov (United States)

    Jeon, D.; Jang, J.-H.; Jin, H.

    2018-05-01

    Studies of the machine imperfections in the RAON superconducting linac (SCL) that employs normal conducting (NC) quadrupoles were done to assess the tolerable error budgets of the machine imperfections that ensure operation of the beam. The studies show that the beam loss requirement is met even before the orbit correction and that the beam loss requirement is met even without the MHB (multi-harmonic buncher) and VE (velocity equalizer) thanks to the RAON's radio-frequency quadrupole (RFQ) design feature. For the low energy section of the linac (SCL3), a comparison is made between the two superconducting linac lattice types: one lattice that employs NC quadrupoles and the other that employs SC solenoids. The studies show that both lattices meet the beam loss requirement after the orbit correction. However, before the orbit correction, the lattice employing SC solenoids does not meet the beam loss requirement and can cause a significant beam loss, while the lattice employing NC quadrupoles meets the requirement. For the lattice employing SC solenoids, care must be taken during the beam commissioning.

  13. Review of superconducting linacs

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1992-01-01

    This paper summarizes the status of the technology of superconducting (SC) linacs designed for the acceleration of ions. The emphasis is on the technical issues involved, with only brief descriptions of the numerous linacs now in operation or under construction. Recent developments of special interest are treated in more detail, and remaining technical challenges are outlined. The technology required for acceleration of ions with velocity β ∼ 1 is not discussed because it is almost the same as for relativistic electrons. That is, this paper is mainly about SC linacs for low-velocity heavy ions. (Author) 5 tabs., 6 figs., 29 refs

  14. Review of induction LINACS

    International Nuclear Information System (INIS)

    Faltens, A.; Keefe, D.

    1981-10-01

    There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

  15. Review of induction linacs

    International Nuclear Information System (INIS)

    Faltens, A.; Keefe, D.

    1982-01-01

    There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of several kiloamps of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

  16. Feasibility and normal values of an integrated conductivity (Nanoduct™) sweat test system in healthy newborns.

    Science.gov (United States)

    Kuehni, Claudia E; Schindler, Matthias; Mazur, Agnieszka; Malzacher, Andreas; Hornung, René; Barben, Juerg

    2017-07-01

    Nanoduct™ is a simple and practical sweat analysis system measuring conductivity in situ. It requires only three microlitres of sweat, making it especially applicable to newborns. We measured conductivity in 260 healthy term infants at the age of four days, and again at four weeks to determine the proportion of successful tests, test duration, and normal values for sweat conductivity in newborns. Sufficient sweat was collected in 159/260 of four-day olds (61%), and in 225/239 of four-week olds (94%). Mean (sd) test duration was 27 (5) and 25 (5) min. Mean (sd, range) conductivity was 53mmol/l (16, 8-114) at age four days, and 36 (9, 12-64) at four weeks. Determination of sweat conductivity using Nanoduct™ cannot be recommended for four-day old newborns. However, at the age of four weeks the success rate is high (94%), and conductivity values at that age are comparable to older healthy children. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  17. Operative findings of conductive hearing loss with intact tympanic membrane and normal temporal bone computed tomography.

    Science.gov (United States)

    Kim, Se-Hyung; Cho, Yang-Sun; Kim, Hye Jeong; Kim, Hyung-Jin

    2014-06-01

    Despite recent technological advances in diagnostic methods including imaging technology, it is often difficult to establish a preoperative diagnosis of conductive hearing loss (CHL) in patients with an intact tympanic membrane (TM). Especially, in patients with a normal temporal bone computed tomography (TBCT), preoperative diagnosis is more difficult. We investigated middle ear disorders encountered in patients with CHL involving an intact TM and normal TBCT. We also analyzed the surgical results with special reference to the pathology. We reviewed the medical records of 365 patients with intact TM, who underwent exploratory tympanotomy for CHL. Fifty nine patients (67 ears, eight bilateral surgeries) had a normal preoperative TBCT findings reported by neuro-radiologists. Demographic data, otologic history, TM findings, preoperative imaging findings, intraoperative findings, and pre- and postoperative audiologic data were obtained and analyzed. Exploration was performed most frequently in the second and fifth decades. The most common postoperative diagnosis was stapedial fixation with non-progressive hearing loss. The most commonly performed hearing-restoring procedure was stapedotomy with piston wire prosthesis insertion. Various types of hearing-restoring procedures during exploration resulted in effective hearing improvement, especially with better outcome in the ossicular chain fixation group. In patients with CHL who have intact TM and normal TBCT, we should consider an exploratory tympanotomy for exact diagnosis and hearing improvement. Information of the common operative findings from this study may help in preoperative counseling.

  18. 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)

  19. Brookhaven Linac Isotope Producer

    Data.gov (United States)

    Federal Laboratory Consortium — The Brookhaven Linac Isoptope Producer (BLIP)—positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis—produces commercially...

  20. Electron linac injector developments

    International Nuclear Information System (INIS)

    Fraser, J.S.

    1986-01-01

    There is a continuing demand for improved injectors for electron linacs. Free-electron laser (FEL) oscillators require pulse trains of high brightness and, in some applications, high average power at the same time. Wakefield-accelerator and laser-acceleration experiments require isolated bunches of high peak brightness. Experiments with alkali-halide photoemissive and thermionic electron sources in rf cavities for injector applications are described. For isolated pulses, metal photocathodes (illuminated by intense laser pulses) are being employed. Reduced emittance growth in high-peak-current electron injectors may be achieved by linearizing the cavity electric field's radial component and by using high field strengths at the expense of lower shunt impedance. Harmonically excited cavities have been proposed for enlarging the phase acceptance of linac cavities and thereby reducing the energy spread produced in the acceleration process. Operation of injector linacs at a subharmonic of the main linac frequency is also proposed for enlarging the phase acceptance

  1. Cs2Te normal conducting photocathodes in the superconducting rf gun

    CERN Document Server

    Xiang, R; Buettig, H; Janssen, D; Justus, M; Lehnert, U; Michel, P; Murcek, P; Schamlott, A; Schneider, Ch; Schurig, R; Staufenbiel, F; Teichert, J

    2010-01-01

    The superconducting radio frequency photoinjector (SRF gun) is one of the latest applications of superconducting rf technology in the accelerator field. Since superconducting photocathodes with high quantum efficiency are yet unavailable, normal conducting cathode material is the main choice for SRF photoinjectors. However, the compatibility between the photocathode and the cavity is one of the challenges for this concept. Recently, a SRF gun with Cs2Te cathode has been successfully operated in Forschungszentrum Dresden-Rossendorf. In this paper, we will present the physical properties of Cs2Te photocathodes in the SC cavity, such as the quantum efficiency, the lifetime, the rejuvenation, the charge saturation, and the dark current.

  2. Studies on normal-conducting coils for Wendelstein VII-X

    International Nuclear Information System (INIS)

    Harmeyer, E.; Kisslinger, J.; Rau, F.; Sapper, J.; Wobig, H.

    1990-08-01

    For Wendelstein VII-X, the next step stellarator experiment at IPP Garching, a Helias configuration has been chosen. The goals of Wendelstein VII-X are to continue the development of the modular stellarator and to demonstrate the reactor capability of this stellarator line. The main data of the selected HS5-10 configuration with five field periods are: major radius R 0 = 5.5 m, magnetic induction B 0 = 3 T and stored magnetic energy W ≅ 0.6 GJ. For comparison with the superconducting coil system which is foreseen for Wendelstein VII-X, a pulsed water-cooled normal-conducting version has been designed in order to explore the limitations and restrictions of this approach. Limitations are the high ohmic power dissipated in the coils and the electric energy currently available at IPP. Normal-conducting coils would allow to apply the well-known techniques in manufactoring these coils, as successful in use in the Wendelstein VII-AS experiment. But these techniques are applicable also for the conductor proposed for the superconducting coils of Wendelstein VII-X. In this report the time-dependent current and resistance of the coil system circuit is considered; the electric power needed, the total dissipated energy, and the temperature rise of the coil copper is calculated. Scaling laws are derived and parameter studies are made by varying the geometrical dimensions of the system. (orig.)

  3. Variable-energy drift-tube linacs

    International Nuclear Information System (INIS)

    Swenson, D.A.; Boyd, T.J. Jr.; Potter, J.M.; Stovall, J.E.

    1982-01-01

    Practical applications of ion linacs are more viable now than ever before because of the recent development of the radio-frequency quadrupole accelerating structure, as well as other technological advances developed under the Pion Generator for Medical Irradiations program. This report describes a practical technique for varying the energy of drift-tube linacs and thus further broadening the possibilities for linac applications. This technique involves using the post couplers (normally used to flatten and stabilize the electric fields) to create a step in the fields, thus terminating the acceleration process. In the examples given for a 70-MeV accelerator design, when using this technique the energy is continually variable down to 20 MeV, while maintaining a small energy spread

  4. Normal-state conductance used to probe superconducting tunnel junctions for quantum computing

    Energy Technology Data Exchange (ETDEWEB)

    Chaparro, Carlos; Bavier, Richard; Kim, Yong-Seung; Kim, Eunyoung; Oh, Seongshik [Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Kline, Jeffrey S; Pappas, David P, E-mail: carlosch@physics.rutgers.ed, E-mail: ohsean@physics.rutgers.ed [National Institute of Standards and Technology, Boulder, CO 80305 (United States)

    2010-04-15

    Here we report normal-state conductance measurements of three different types of superconducting tunnel junctions that are being used or proposed for quantum computing applications: p-Al/a-AlO/p-Al, e-Re/e-AlO/p-Al, and e-V/e-MgO/p-V, where p stands for polycrystalline, e for epitaxial, and a for amorphous. All three junctions exhibited significant deviations from the parabolic behavior predicted by the WKB approximation models. In the p-Al/a-AlO/p-Al junction, we observed enhancement of tunneling conductances at voltages matching harmonics of Al-O stretching modes. On the other hand, such Al-O vibration modes were missing in the epitaxial e-Re/e-AlO/p-Al junction. This suggests that absence or existence of the Al-O stretching mode might be related to the crystallinity of the AlO tunnel barrier and the interface between the electrode and the barrier. In the e-V/e-MgO/p-V junction, which is one of the candidate systems for future superconducting qubits, we observed suppression of the density of states at zero bias. This implies that the interface is electronically disordered, presumably due to oxidation of the vanadium surface underneath the MgO barrier, even if the interface was structurally well ordered, suggesting that the e-V/e-MgO/p-V junction will not be suitable for qubit applications in its present form. This also demonstrates that the normal-state conductance measurement can be effectively used to screen out low quality samples in the search for better superconducting tunnel junctions.

  5. Linac design for the LCLS project at SLAC

    International Nuclear Information System (INIS)

    Bharadwaj, V.K.; Bane, K.; Clendenin, J.

    1997-05-01

    The Linac Coherent Light Source (LCLS) at SLAC is being designed to produce intense, coherent 0.15-nm x-rays. These x-rays will be produced by a single pass of a 15 GeV bunched electron beam through a long undulator. Nominally, the bunches have a charge of 1 nC, normalized transverse emittances of less than 1.5π mm-mr and an rms bunch length of 20 μm. The electron beam will be produced using the last third of the SLAC 3-km linac in a manner compatible with simultaneous operation of the remainder of the linac for PEP-II. The linac design necessary to produce an electron beam with the required brightness for LCLS is discussed, and the specific linac modifications are described

  6. Design and Beam Dynamics Studies of a Multi-Ion Linac Injector for the JLEIC Ion Complex

    Energy Technology Data Exchange (ETDEWEB)

    Ostroumov, P. N.; Plastun, A. S.; Mustapha, B.; Conway, Z. A.

    2016-01-01

    The electron-ion collider (JLEIC) being proposed at JLab requires a new ion accelerator complex which includes a linac capable of delivering any ion beam from hydrogen to lead to the booster. We are currently developing a linac which consists of several ion sources, a normal conducting (NC) front end, up to 5 MeV/u, and a SC section for energies > 5 MeV/u. This design work is focused on the beam dynamics and electrodynamics studies performed to design efficient and cost-effective accelerating structures for both the NC and SC sections of the linac. Currently, we are considering two separate RFQs for the heavy-ion and light-ion beams including polarized beams, and different types of NC accelerating structures downstream of the RFQ. Quarter-wave and half-wave resonators can be effectively used in the SC section.

  7. High power coupler issues in normal conducting and superconducting accelerator applications

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, H. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2001-02-01

    The ceramic material (Al{sub 2}O{sub 3}) commonly used for the klystron output coupler in normal conducting, and for an input coupler to superconducting cavities is one of the most troublesome parts in accelerator applications. But the performance can be improved very much by starting with high purity (>99.9%) alumina powder of controlled grain-size (0.1-0.5-{mu}m), and reducing the magnesium (Mg) sintering-binder to lower the dielectric loss to the order of 10{sup -4} at S-band frequencies. It has been confirmed that the new ceramic can stand a peak S-band frequency rf power of up to 300 MW and 2.5 {mu}sec pulse width. (author)

  8. Cs_{2}Te normal conducting photocathodes in the superconducting rf gun

    Directory of Open Access Journals (Sweden)

    R. Xiang

    2010-04-01

    Full Text Available The superconducting radio frequency photoinjector (SRF gun is one of the latest applications of superconducting rf technology in the accelerator field. Since superconducting photocathodes with high quantum efficiency are yet unavailable, normal conducting cathode material is the main choice for SRF photoinjectors. However, the compatibility between the photocathode and the cavity is one of the challenges for this concept. Recently, a SRF gun with Cs_{2}Te cathode has been successfully operated in Forschungszentrum Dresden-Rossendorf. In this paper, we will present the physical properties of Cs_{2}Te photocathodes in the SC cavity, such as the quantum efficiency, the lifetime, the rejuvenation, the charge saturation, and the dark current.

  9. A 201-MHz Normal Conducting RF Cavity for the International MICE Experiment

    International Nuclear Information System (INIS)

    Li, D.; DeMello, A.J.; Virostek, Steve; Zisman, Michael S.; Rimmer, Robert

    2008-01-01

    MICE is a demonstration experiment for the ionization cooling of muon beams. Eight RF cavities are proposed to be used in the MICE cooling channel. These cavities will be operated in a strong magnetic field; therefore, they must be normal conducting. The cavity design and construction are based on the successful experience and techniques developed for a 201-MHz prototype cavity for the US MUCOOL program. Taking advantage of a muon beamΛ s penetration property, the cavity employs a pair of curved thin beryllium windows to terminate conventional beam irises and achieve higher cavity shunt impedance. The cavity resembles a round, closed pillbox cavity. Two half-shells spun from copper sheets are joined by e-beam welding to form the cavity body. There are four ports on the cavity equator for RF couplers, vacuum pumping and field probes. The ports are formed by means of an extruding technique.

  10. Normal-Conducting Separation and Compensation Dipoles for the LHC Experimental Insertions

    CERN Document Server

    Ramberger, S; Cornuet, D; Gérard, D; Gurov, D; Hans, O; Kalbreier, Willi; Kiselev, O; Morozov, I; Ogurtsov, A; Petrov, V; de Rijk, G; Ruvinsky, E; Sukhanov, A; Zhilayev, K

    2006-01-01

    The experimental insertions of the LHC make use of normal-conducting magnets to provide for part of the beam separation and to compensate the effect of two large spectrometer dipoles. Three different types with respect to the length were designed and are based on the same type of lamination. The main type of magnet MBXW has a core length of 3.4 m while the MBXWT and MBXWS magnets are 1.5 m and 0.75 m long versions respectively. The magnet design was done in collaboration between CERN and BINP and the dipole magnets are produced by BINP. So far all three MBXWS magnets, all three MBXWT magnets and fifteen of twenty-nine MBXW magnets have been manufactured and delivered to CERN. The report presents the main design issues and results of the acceptance tests including mechanical, electrical and magnetic field measurements.

  11. Tunneling Conductance in Two-Dimensional Junctions between a Normal Metal and a Ferromagnetic Rashba Metal

    Science.gov (United States)

    Oshima, Daisuke; Taguchi, Katsuhisa; Tanaka, Yukio

    2018-03-01

    We have studied charge transport in a ferromagnetic Rashba metal (FRM), where both Rashba type spin-orbit coupling (RSOC) and exchange coupling coexist. It has nontrivial metallic states, i.e., a normal Rashba metal (NRM), anomalous Rashba metal (ARM), and Rashba ring metal (RRM), and they are manipulated by tuning the Fermi level with an applied gate voltage. We theoretically studied the tunneling conductance (G) in a normal metal/FRM junction by changing the Fermi level via an applied gate voltage (Vg) on the FRM. We found a wide variation in the Vg dependence of G, which depends on the metallic states. In an NRM, the Vg dependence of G is the same as that in a conventional two-dimensional system. However, in an ARM, the Vg dependence of G is similar to that in a conventional one- (two-)dimensional system for a large (small) RSOC. Furthermore, in an RRM, which is generated by a large RSOC, the Vg dependence of G is similar to that in the one-dimensional system. In addition, these anomalous properties stem from the density of states in the ARM and RRM caused by the large RSOC and exchange coupling rather than the spin-momentum locking of RSOC.

  12. High field electron linacs

    International Nuclear Information System (INIS)

    Le Duff, J.

    1985-12-01

    High field electron linacs are considered as potential candidates to provide very high energies beyond LEP. Since almost twenty years not much improvement has been made on linac technologies as they have been mostly kept at low and medium energies to be used as injectors for storage rings. Today, both their efficiency and their performances are being reconsidered, and for instance the pulse compression sheme developed at SLAC and introduced to upgrade the energy of that linac is a first step towards a new generation of linear accelerators. However this is not enough in terms of power consumption and more development is needed to improve both the efficiency of accelerating structures and the performances of RF power sources

  13. Open-type congenital cholesteatoma: differential diagnosis for conductive hearing loss with a normal tympanic membrane.

    Science.gov (United States)

    Kim, Se-Hyung; Cho, Yang-Sun; Chu, Ho-Suk; Jang, Jeon-Yeob; Chung, Won-Ho; Hong, Sung Hwa

    2012-06-01

    In patients with progressive conductive hearing loss and a normal tympanic membrane (TM), and with soft tissue density in the middle ear cavity (MEC) on temporal bone computed tomography (TBCT) scan, open-type congenital cholesteatoma (OCC) should be highly suspected and a proper surgical plan that includes mastoid exploration and second-stage operation is required. The clinical presentation of OCC is very similar to congenital ossicular anomaly (COA) presenting with a conductive hearing loss with intact TM. Therefore, it is challenging to make a correct preoperative diagnosis in patients with OCC. We evaluated the clinical characteristics of OCC compared with those of COA to find diagnostic clues useful in diagnosis of OCC. The medical records of 12 patients with surgically proven OCC and 14 patients with surgically proven COA were reviewed for demographic data, otologic history, preoperative TBCT findings, intraoperative findings, and pre- and postoperative audiologic data. There was no difference between OCC and COA based on demographic data, preoperative hearing, and ossicular status on TBCT. However, the presence of progressive hearing loss, soft tissue density in the MEC on TBCT scan, and the need for mastoid surgery and second-stage operation were significantly more frequent in OCC patients.

  14. RF linacs for FELs

    International Nuclear Information System (INIS)

    Schwettman, H.A.

    1992-01-01

    There are twenty rf linac-driven Free Electron Lasers (FELs) existing or under construction throughout the world and proposals for several more. A number of these FELs have recently been established as facilities to produce coherent optical beams for materials and biomedical research. Both short pulse low duty factor and long pulse high duty factor linac-driven FELs will be discussed. Accelerator issues that influence the performance of an FEL as a scientific instrument will be indicated. (Author) 6 refs., 6 figs., 2 tabs

  15. System design of a proton linac for the neutron science project at Japan Atomic Energy Research Institute

    International Nuclear Information System (INIS)

    Hasegawa, Kazuo; Mizumoto, Motoharu; Ouchi, Nobuo; Honda, Yoichiro; Ino, Hiroshi

    1999-01-01

    The Japan Atomic Energy Research Institute has been proposing the Neutron Science Project (NSP). The NSP requires pulse and CW proton beams with an energy of 1.5 GeV and an average beam power up to 8MW. This paper describes design concepts and parameters of the linac. A front end part of the linac, which consists of RFQ, DTL and SDTL sections, uses normal conducting structures and a high energy part uses superconducting (SC) structures. The linac has two injector lines for the pulse and the CW modes, respectively, and the two lines merge at 7 MeV. The total linac length is approximately 900 m and most of the part (>75%) is the superconducting section. An equipartitioning design, which is a new idea to suppress an emittance growth for high power linacs, has been taken for the DTL, the SDTL and the SC sections. Compared with the conventional constant phase advance design scheme, the equipartitioning design scheme is proved to be a good approach to suppress the longitudinal emittance growth. (author)

  16. Fermilab: Linac upgrade

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The Fermilab linear accelerator (Linac) was conceived 20 years ago, produced its first 200 MeV proton beam on 30 November 1970 and has run without major interruption ever since. Demands have steadily increased through the added complexity of the downstream chain of accelerators and by the increased patient load of the Neutron Therapy Facility

  17. TOP LINAC design

    International Nuclear Information System (INIS)

    Picardi, L.; Ronsivalle, C.; Vignati, A.

    1997-11-01

    The report describes a linear accelerator for protons named TOP LINAC designed for the TOP (Terapia Oncologica con Protoni, Oncological Protontherapy) project launched by the Italian National Institute of Health (Istituto Superiore di Sanita', ISS) to explore in collaboration with the biggest Oncological Hospital in Rome (Istituto Regina Elena, IRE) the potentialities of the therapy with accelerated protons and establish guide lines for the application of this new type of radiotherapy in comparison with the more traditional electron and x-rays radiotherapy. The concept of a compact accelerator for protontherapy applications bore within the Italian Hadrontherapy Collaboration (TERA Collaboration) with the aim to diffuse the protontherapy on the National territory. The ISS program plans to use the TOP linac proton beam also for production of PET (Positron Emission Tomography) radioisotopes and radiobiology studies. Official agreements are in course between ISS and ENEA which provides its experience in the industrial and medical accelerators for the design and the construction of the TOP linac. The accelerator that will be the first 3 GHz proton linac in the world, will be composed of a 428.3 MHz 7 Me V RFQ + DTL injector followed by a 7-65 Me V section of a 3 GHz SCDTL structure and a 65 - 200 Me V variable energy SCL 3 GHz structure. In particular the SCDTL section uses a highly innovative accelerating structure patented by ENEA. In this report the clinical and physical requests are discussed and a preliminary design of the whole machine is given

  18. High-gradient normal-conducting RF structures for muon cooling channels

    International Nuclear Information System (INIS)

    Corlett, J.N.; Green, M.A.; Hartman, N.; Ladran, A.; Li, D.; MacGill, R.; Rimmer, R.; Moretti, A.; Jurgens, T.; Holtkamp, N.; Black, E.; Summers, D.; Booke, M.

    2001-01-01

    We present a status report on the research and development of high-gradient normal-conducting RF structures for the ionization cooling of muons in a neutrino factory or muon collider. High-gradient RF structures are required in regions enclosed in strong focusing solenoidal magnets, precluding the application of superconducting RF technology [1]. We propose using linear accelerating structures, with individual cells electromagnetically isolated, to achieve the required gradients of over 15 MV/m at 201 MHz and 30 MV/m at 805 MHz. Each cell will be powered independently, and cell length and drive phase adjusted to optimize shunt impedance of the assembled structure. This efficient design allows for relatively small field enhancement on the structure walls, and an accelerating field approximately 1.7 times greater than the peak surface field. The electromagnetic boundary of each cell may be provided by a thin Be sheet, or an assembly of thin-walled metal tubes. Use of thin, low-Z materials will allow passage of the muon beams without significant deterioration in beam quality due to scattering. R and D in design and analysis of robust structures that will operate under large electric and magnetic fields and RF current heating are discussed, including the experimental program based in a high-power test laboratory developed for this purpose

  19. Drift tubes of Linac 2

    CERN Multimedia

    CERN PhotoLab

    1977-01-01

    With the advent of the 800 MeV PS Booster in 1972, the original injector of the PS, a 50 MeV Alvarez-type proton linac, had reached its limits, in terms of intensity and stability. In 1973 one therefore decided to build a new linac (Linac 2), also with a drift-tube Alvarez structure and an energy of 50 MeV. It had a new Cockcroft-Walton preinjector with 750 keV, instead of the previous one with 500 keV. Linac 2 was put into service in 1980. The old Linac 1 was then used for the study of, and later operation with, various types of ions. This picture shows Linac 2 drift-tubes, suspended on stems coming from the top, in contrast to Linac 1, where the drift-tubes stood on stems coming from the bottom.

  20. Reflectance Measures from Infant Ears With Normal Hearing and Transient Conductive Hearing Loss.

    Science.gov (United States)

    Voss, Susan E; Herrmann, Barbara S; Horton, Nicholas J; Amadei, Elizabeth A; Kujawa, Sharon G

    2016-01-01

    The objective is to develop methods to utilize newborn reflectance measures for the identification of middle-ear transient conditions (e.g., middle-ear fluid) during the newborn period and ultimately during the first few months of life. Transient middle-ear conditions are a suspected source of failure to pass a newborn hearing screening. The ability to identify a conductive loss during the screening procedure could enable the referred ear to be either (1) cleared of a middle-ear condition and recommended for more extensive hearing assessment as soon as possible, or (2) suspected of a transient middle-ear condition, and if desired, be rescreened before more extensive hearing assessment. Reflectance measurements are reported from full-term, healthy, newborn babies in which one ear referred and one ear passed an initial auditory brainstem response newborn hearing screening and a subsequent distortion product otoacoustic emission screening on the same day. These same subjects returned for a detailed follow-up evaluation at age 1 month (range 14 to 35 days). In total, measurements were made on 30 subjects who had a unilateral refer near birth (during their first 2 days of life) and bilateral normal hearing at follow-up (about 1 month old). Three specific comparisons were made: (1) Association of ear's state with power reflectance near birth (referred versus passed ear), (2) Changes in power reflectance of normal ears between newborn and 1 month old (maturation effects), and (3) Association of ear's newborn state (referred versus passed) with ear's power reflectance at 1 month. In addition to these measurements, a set of preliminary data selection criteria were developed to ensure that analyzed data were not corrupted by acoustic leaks and other measurement problems. Within 2 days of birth, the power reflectance measured in newborn ears with transient middle-ear conditions (referred newborn hearing screening and passed hearing assessment at age 1 month) was significantly

  1. Conductive Hearing Loss in Autistic, Learning-Disabled, and Normal Children.

    Science.gov (United States)

    Smith, Donald E. P.; And Others

    1988-01-01

    Repeated impedance measures were given over five weeks to 11 autistic, 20 learning-disabled, and 20 normal children. A repeated measures analysis of variance led to the conclusion that fluctuating, negative middle ear pressure greater than normal characterizes both autistic and learning-disabled children with the more abnormal pressures typical in…

  2. Cystic fibrosis transmembrane conductance regulator is correlated closely with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters.

    Science.gov (United States)

    Jiang, L-Y; Shan, J-J; Tong, X-M; Zhu, H-Y; Yang, L-Y; Zheng, Q; Luo, Y; Shi, Q-X; Zhang, S-Y

    2014-10-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20-29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30-39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer-assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (P sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age. © 2013 Blackwell Verlag GmbH.

  3. Beam Loss in Linacs

    CERN Document Server

    Plum, M.A.

    2016-01-01

    Beam loss is a critical issue in high-intensity accelerators, and much effort is expended during both the design and operation phases to minimize the loss and to keep it to manageable levels. As new accelerators become ever more powerful, beam loss becomes even more critical. Linacs for H- ion beams, such as the one at the Oak Ridge Spallation Neutron Source, have many more loss mechanisms compared to H+ (proton) linacs, such as the one being designed for the European Spallation Neutron Source. Interesting H- beam loss mechanisms include residual gas stripping, H+ capture and acceleration, field stripping, black-body radiation and the recently discovered intra-beam stripping mechanism. Beam halo formation, and ion source or RF turn on/off transients, are examples of beam loss mechanisms that are common for both H+ and H- accelerators. Machine protection systems play an important role in limiting the beam loss.

  4. Radioisotope production linac

    International Nuclear Information System (INIS)

    Stovall, J.E.; Hansborough, L.D.; O'Brien, H.A.

    1981-01-01

    A 70-MeV proton beam would open a new family of medical radioisotopes (including the important 123 I) to wide application. A 70-MeV, 500-μA linac is described, based on recent innovations in accelerator technology. It would be 27.3 m long, cost approx. $6 million, and the cost of power deposited in the radioisotope-production target is comparable to existing cyclotrons. By operating the rf-power system to its full capability, the same accelerator is capable of producing a 1140-μA beam, and the cost per beam watt on the target is less than half that of comparable cyclotrons. The technology to build such a linac is in a mature stage of developmnt, ready for use by industry

  5. Linacs for medical isotope production

    International Nuclear Information System (INIS)

    Pramudita, A.

    2012-01-01

    This paper reviews efforts on using high energy (25-30 MeV) and high power (10-20 kW) electron linacs and lower energy (7 MeV) proton linacs for medical radioisotope production. Using high energy x-rays from the electron linacs, PET (Positron Emission Tomography) radioisotopes are produced through photonuclear reactions such as 19 F(γ,n) 18 F, which also allow production of other PET radionuclides 11 C, 13 N, and 15 O. Other mostly used medical radionuclides 99m Tc can also be obtained by using the electron linacs, through photofission or photonuclear reactions. Proton linacs for PET have also been recently developed and the product has been available in the market since 2005. The linacs have been tested for 18 F production. As a proton accelerator, the target systems and nuclear reactions are similar to the ones used in PET cyclotrons. (author)

  6. The Fermilab 400-MeV Linac Upgrade

    International Nuclear Information System (INIS)

    Schmidt, C.W.

    1993-05-01

    The Fermilab Linac Upgrade will increase the linac energy from 201 MeV to 401.5 MeV. Seven accelerating modules, composed of 805-MHz side-coupled cells, will accelerate H - beams from 116.5 to 401.5 MeV. The side-coupled structure (SCS) has been built, tuned, tested to full power, and placed in the linac enclosure along side the operating Linac. All seven accelerating modules, each containing four sections of sixteen cells, have been connected to 12-MW power klystrons and tested to full power for a significant period. The transition section to match the beam from the 201.25-MHz drift-tube linac to the SCS, consisting of a sixteen-cell cavity and a vernier four-cell cavity, has also been tested at full power. A new import line from the Linac to the Booster synchrotron with a new Booster injection girder is to be installed. Removal of the last four Alvarez linac tanks (116.5 to 201 MeV) and beam-line installation of the Upgrade components is to begin in early June 1993 and should take about 12 weeks. Beam commissioning of the project will follow and normal operation is expected in a short period. In preparation for beam commissioning, studies are being done with done operating linac to characterize the beam at transition and prepare for phase, amplitude and energy measurements to commission the new linac. The past, present and future activities of the 400-MeV Upgrade will be reviewed

  7. Injector linac of SPring-8

    International Nuclear Information System (INIS)

    Yoshikawa, H.; Hori, T.; Suzuki, S.; Yanagida, K.; Itoh, Y.; Mizuno, A.; Taniuchi, T.; Sakaki, H.; Kuba, A.; Fukushima, S.; Kobayashi, T.; Asaka, T.; Yokomizo, H.

    1996-01-01

    The linac that is SPring-8 injector was completed and started operation from August 1. A beam was able to be transported to the final beam dumping at a tail end on August 8. From now on this linac carries out beam adjustment and be scheduled to do a beam injection to a synchrotron in October. The construction and fundamental performance of the linac are described. (author)

  8. Superconducting heavy-ion linacs

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1977-01-01

    A summary is given of plans developed by four different groups for the construction of small superconducting linacs to boost the energy of heavy ions from existing tandem electrostatic accelerators. The projects considered are the linac under construction at Argonne and the design efforts at Karlsruhe, at Stanford, and by a Cal Tech-Stony Brook collaboration. The intended uses of the accelerator systems are stated. Beam dynamics of linacs formed of short independently-phased resonators are reviewed, and the implications for performance are discussed. The main parameters of the four linacs are compared, and a brief analysis of accelerating structures is given

  9. High-beta linac structures

    International Nuclear Information System (INIS)

    Schriber, S.O.

    1979-01-01

    Accelerating structures for high-beta linacs that have been and are in use are reviewed in terms of their performance. Particular emphasis is given to room-temperature structures and the disk-and-washer structure. The disk-and-washer structure has many attractive features that are discussed for pulsed high-gradient linacs, for 100% duty-cycle medium-gradient linacs and for high-current linacs requiring maximal amounts of stored energy in the electric fields available to the beam

  10. Mechanical considerations in cw linacs

    International Nuclear Information System (INIS)

    King, J.D.

    1985-01-01

    An 80-MHz radio-frequency quadrupole (RFQ) linac has been designed, fabricated and operated at 100% duty factor (cw) for the Fusion Materials Irradiation Test (FMIT) project at Los Alamos. This paper describes the design features, fabrication techniques, and operational problems of the device. The RFQ is an assembly of heavy steel, copper-plated weldments. It measures about 15 ft (4.5 m) long by 5 ft (1.5 m) in diameter and weighs over 12 t. Major components are two pair of diametrically orthogonal vanes mounted in a core cylinder. The core is assembled into a manifold cylinder that couples rf power into the vane quadrants. The design features discussed include assembly of hollow wall, flood-cooled components; high-conductivity rf seals; removable and adjustable vanes; and tuning devices. Fabrication challenges such as close-tolerance weldments, vane-tip-contour machining and large-component plating requirements are covered

  11. Linac4 45 keV Proton Beam Measurements

    CERN Document Server

    Bellodi, G; Hein, L M; Lallement, J-B; Lombardi, A M; Midttun, O; Scrivens, R; Posocco, P A

    2013-01-01

    Linac4 is a 160 MeV normal-conducting H- linear accelerator, which will replace the 50 MeV proton Linac2 as injector for the CERN proton complex. Commissioning of the low energy part - comprising the H - source, a 45 keV Low Energy Beam Transport line (LEBT), a 3 MeV Radiofrequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) - will start in fall 2012 on a dedicated test stand installation. In preparation to this, preliminary measurements were taken using a 45 keV proton source and a temporary LEBT setup, with the aim of characterising the output beam by comparison with the predictions of simulations. At the same time this allowed a first verification of the functionalities of diagnostics instrumentation and acquisition software tools. Measurements of beam profile, emittance and intensity were taken in three different setups: right after the source, after the first and after the second LEBT solenoids respectively. Particle distributions were reconstructed from emittance scan...

  12. A proposed injector for the LCLS linac

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Bharadwaj, V.K.; Emma, P.; Miller, R.H.; Palmer, D.T.; Woodley, M.D.

    1996-11-01

    The Linac Coherent Light Source (LCLS) will use the last portion of the SLAC accelerator as a driver for a short wavelength FEL. The injector must produce 1-nC, 3-ps rms electron bunches at a repetition rate of up to 120 Hz with a normalized rms emittance of about 1 mm-mrad. The injector design takes advantage of the photocathode rf gun technology developed since its conception in the mid 1980's, in particular the S-band rf gun developed by the SLAC/BNL/UCLA collaboration, and emittance compensation techniques developed in the last decade. The injector beamline has been designed using the SUPERFISH, POISSON, PARMELA, and TRANSPORT codes in a consistent way to simulate the beam from the gun up to the entrance of the main accelerator linac where the beam energy is 150 MeV. PARMELA simulations indicate that at 150 MeV, space charge effects are negligible

  13. High current induction linacs

    International Nuclear Information System (INIS)

    Barletta, W.; Faltens, A.; Henestroza, E.; Lee, E.

    1994-07-01

    Induction linacs are among the most powerful accelerators in existence. They have accelerated electron bunches of several kiloamperes, and are being investigated as drivers for heavy ion driven inertial confinement fusion (HIF), which requires peak beam currents of kiloamperes and average beam powers of some tens of megawatts. The requirement for waste transmutation with an 800 MeV proton or deuteron beam with an average current of 50 mA and an average power of 40 MW lies midway between the electron machines and the heavy ion machines in overall difficulty. Much of the technology and understanding of beam physics carries over from the previous machines to the new requirements. The induction linac allows use of a very large beam aperture, which may turn out to be crucial to reducing beam loss and machine activation from the beam halo. The major issues addressed here are transport of high intensity beams, availability of sources, efficiency of acceleration, and the state of the needed technology for the waste treatment application. Because of the transformer-like action of an induction core and the accompanying magnetizing current, induction linacs make the most economic sense and have the highest efficiencies with large beam currents. Based on present understanding of beam transport limits, induction core magnetizing current requirements, and pulse modulators, the efficiencies could be very high. The study of beam transport at high intensities has been the major activity of the HIF community. Beam transport and sources are limiting at low energies but are not significant constraints at the higher energies. As will be shown, the proton beams will be space-charge-dominated, for which the emittance has only a minor effect on the overall beam diameter but does determine the density falloff at the beam edge

  14. SRF and RF systems for LEReC Linac

    Energy Technology Data Exchange (ETDEWEB)

    Belomestnykh, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Brutus, J. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); McIntyre, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Polizzo, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tuozzolo, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Veshcherevich, V. [Cornell Univ., Ithaca, NY (United States); Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xiao, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xu, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zaltsman, A. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    The Low Energy RHIC electron Cooling (LEReC) is under development at BNL to improve RHIC luminosity at low energies. It will consist of a short electron linac and two cooling sections, one for blue and one for yellow rings. For the first stage of the project, LEReC-I, we will install a 704 MHz superconducting RF cavity and three normal conducting cavities operating at 9 MHz, 704 MHz and 2.1 GHz. The SRF cavity will boost the electron beam energy up to 2 MeV. The warm cavities will be used to correct the energy spread introduced in the SRF cavity. The paper describes layouts of the SRF and RF systems, their parameters and status.

  15. Compact LINAC for deuterons

    International Nuclear Information System (INIS)

    Kurennoy, S.S.; O'Hara, J.F.; Rybarcyk, L.J.

    2008-01-01

    We are developing a compact deuteron-beam accelerator up to the deuteron energy of a few MeV based on room-temperature inter-digital H-mode (IH) accelerating structures with the transverse beam focusing using permanent-magnet quadrupoles (PMQ). Combining electromagnetic 3-D modeling with beam dynamics simulations and thermal-stress analysis, we show that IHPMQ structures provide very efficient and practical accelerators for light-ion beams of considerable currents at the beam velocities around a few percent of the speed of light. IH-structures with PMQ focusing following a short RFQ can also be beneficial in the front end of ion linacs.

  16. CONFERENCE: Linacs at Seeheim

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-07-15

    The 12th Linear Accelerator Conference, organized by GSI Darmstadt, was held from 8-11 May at the Lufthansa Schulungszentrum in Seeheim, West Germany. It was the first of this series of Linac Accelerator Conferences - started in 1961 with 20 participants and 17 contributions at Brookhaven - held outside North America. In Seeheim, 32 invited talks, 11 oral and 98 poster papers were presented to more than 250 participants from the USA, Canada, Europe, Japan, the USSR and China, representing 39 research institutions and 12 industrial laboratories.

  17. CONFERENCE: Linacs at Seeheim

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    The 12th Linear Accelerator Conference, organized by GSI Darmstadt, was held from 8-11 May at the Lufthansa Schulungszentrum in Seeheim, West Germany. It was the first of this series of Linac Accelerator Conferences - started in 1961 with 20 participants and 17 contributions at Brookhaven - held outside North America. In Seeheim, 32 invited talks, 11 oral and 98 poster papers were presented to more than 250 participants from the USA, Canada, Europe, Japan, the USSR and China, representing 39 research institutions and 12 industrial laboratories

  18. NPL superconducting Linac control system

    International Nuclear Information System (INIS)

    Swanson, H.E.; Howe, M.A.; Jackson, L.W.; LaCroix, J.M.; Readdy, H.P.; Storm, D.W.; Van Houten, L.P.

    1985-01-01

    The control system for the NPL Linac is based on a Microvax II host computer connected in a star network with 9 satellite computers. These satellites use single board varsions of DEC's PDP 11 processor. The operator's console uses high performance graphics and touch screen technology to display the current linac status and as the means for interactively controlling the operation of the accelerator

  19. Linac4 Technical Design Report

    CERN Document Server

    Arnaudon, L; Baylac, M; Bellodi, G; Body, Y; Borburgh, J; Bourquin, P; Broere, J; Brunner, O; Bruno, L; Carli, C; Caspers, Friedhelm; Cousineau, S M; Cuvet, Y; De Almeida Martins, C; Dobers, T; Fowler, T; Garoby, R; Gerigk, F; Goddard, B; Hanke, K; Hori, M; Jones, M; Kahle, K; Kalbreier, Willi; Kroyer, T; Küchler, D; Lombardi, A M; López-Hernandez, L A; Magistris, M; Martini, M; Maury, S; Page, E; Paoluzzi, M; Pasini, M; Raich, U; Rossi, C; Royer, J P; Sargsyan, E; Serrano, J; Scrivens, R; Silari, M; Timmins, M; Venturini-Delsolaro, W; Vretenar, M; Wegner, R; Weterings, W; Zickler, T

    2006-01-01

    Linac4 is an H- linear accelerator, intended to replace Linac2 as injector to the PS Booster (PSB). By delivering to the PSB a beam at 160 MeV energy, Linac4 will provide the conditions to double the brightness and intensity of the beam from the PSB, thus removing the first bottleneck towards higher brightness for the LHC and simplifying operation. Moreover, this new linac constitutes an essential component of any of the envisaged LHC upgrade scenarios and could open the way to future extensions of the CERN accelerator complex towards higher performance. This Technical Design Report presents a detailed technical overview of the Linac4 design as it stands at end 2006.

  20. The FAIR proton linac

    International Nuclear Information System (INIS)

    Kester, O.

    2015-01-01

    FAIR - the Facility for Antiproton and Ion Research in Europe - constructed at GSI in Darmstadt comprises an international centre of heavy ion accelerators that will drive heavy ion and antimatter research. FAIR will provide worldwide unique accelerator and experimental facilities, allowing a large variety of fore-front research in physics and applied science. FAIR will deliver antiproton and ion beams of unprecedented intensities and qualities. The main part of the FAIR facility is a sophisticated accelerator system, which delivers beams to different experiments of the FAIR experimental collaborations - APPA, NuSTAR, CBM and PANDA - in parallel. Modern H-type cavities offer highest shunt impedances of resonant structures of heavy ion linacs at low beam energies < 20 MeV/u and enable the acceleration of intense proton and ion beams. One example is the interdigital H-type structure. The crossed-bar H-cavities extend these properties to high energies even beyond 100 MeV/u. Compared to conventional Alvarez cavities, these crossed-bar (CH) cavities feature much higher shunt impedance at low energies. The design of the proton linac is based on those cavities

  1. DIFFERENCE IN THE INTENSITY OF DEPRESSION BETWEEN PARENTS HAVING CHILDREN WITH CONDUCT DISORDER AND PARENTS HAVING NORMAL CHILDREN

    Directory of Open Access Journals (Sweden)

    Bindu Meethale Veettil

    2017-10-01

    Full Text Available BACKGROUND Parents experience psychological trauma if they recognise that their children are having conduct disorder, which is unacceptable to the society and against the social norms. The intensity of depression in parents having children with conduct disorder is included in this study. MATERIALS AND METHODS Exploratory research was used in this study as the method of study. A sample was selected from parents having children with conduct disorder reported in various psychiatric settings in Kerala, India, and also from parents having normal children. Random sampling was used for selecting the sample. All the parents of children diagnosed with conduct disorder in the age group of 6 to 12 reported in the psychiatric settings on a random day is selected as sample. Mann-Whitney U test was used for statistical analysis. RESULTS Depression in parents affect their skills in caregiving, support to their children, nurturance and it will affect proper development of children physically and mentally. Similarly, conduct disorder in children will affect their parents mental and social functioning and their life functioning and the parents maybe suffering from depression. Mothers of children with conduct disorders are reported to have exhibit more depressed and they show very poor parenting skills and negative interactions with their children compared to normal mothers. Parents having children with conduct disorder did have higher intensity of depression compared to parents having normal children. CONCLUSION The study hopes to make contributions in identifying the intensity of depression in parents having children with conduct disorder and it’s serious and least recognised impact on their parents. The study will also help to find out the areas in which parents need intervention and to decide which type of therapy will be more helpful to the family as a whole. Identifying and understanding the relevant and feasible components of therapy can then facilitate

  2. One-dimensional classical many-body system having a normal thermal conductivity

    International Nuclear Information System (INIS)

    Casati, G.; Ford, J.; Vivaldi, F.; Visscher, W.M.

    1984-01-01

    By numerically computing orbits for a chaotic, one-dimensional, many-body system placed between two thermal reservoirs, we verify directly that its energy transport obeys the Fourier heat law and we determine its thermal conductivity K. The same value of K is independently obtained by use of the Green-Kubo formalism. These numerical studies verify that chaos is the essential ingredient of diffusive energy transport, and they validate the Green-Kubo formalism

  3. A new technique for precise measurement of thermal conductivity of metals at normal and high temperatures

    International Nuclear Information System (INIS)

    Binkele, L.

    1990-09-01

    Theoretical and experimental investigations on a new measuring technique are described; a technique similar to the well known Kohlrausch measuring technique, which is characterized by direct electrical sample heating. Subject of the investigations is a cylindrical metallic sample, 5 mm thick and 200 mm in length, which is positioned vertically between water-cooled clamps in a vacuum container. The sample can be heated using two simultaneously operating current sources, a 50 Hz-source for axial flow (main heating) as well as a 200 kHz-induction source for generating eddy currents in two short regions above and below the sample centre (additional heating). By using two heating sources different symmetrical temperature profiles in a central eddy-current-free area of about ± 10mm can be produced for any given central sample temperature. The last chapter contains thermal conductivity and electrical resistivity measuring curves for Pt, W, Fe, Ni, Ag, Al, Mg, Ir, Ru, Re, Ho and Y in the temperature range 273 to 1500 K representative of all the metals and alloys investigated. In cases where comparisons with published precise conductivity data, established by other measuring techniques in restricted temperature ranges, were posible, the new measuring method is greatly supported (in the case of Pt, W, Ni, Ag, Al). For the Metals Ir, Ru, Re, Ho and Y high temperature thermal conductivity data are given for the first time. (orig./MM) [de

  4. 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)

  5. Review of superconducting ion linacs

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1992-01-01

    This paper summarizes the status of the technology of superconducting (SC) linacs designed for the acceleration of ions. The emphasis is on the technical issues involved, with only brief descriptions of the numerous linacs now in operation or under construction. Recent developments of special interest are treated in more detail, and remaining technical challenges are outlined. The technology required for the acceleration of ions with velocity β=1 is not discussed because it is almost the same as for relativistic electrons. That is, this paper is mainly about SC linacs for low-velocity heavy ions

  6. Single-Phase Full-Wave Rectifier as an Effective Example to Teach Normalization, Conduction Modes, and Circuit Analysis Methods

    Directory of Open Access Journals (Sweden)

    Predrag Pejovic

    2013-12-01

    Full Text Available Application of a single phase rectifier as an example in teaching circuit modeling, normalization, operating modes of nonlinear circuits, and circuit analysis methods is proposed.The rectifier supplied from a voltage source by an inductive impedance is analyzed in the discontinuous as well as in the continuous conduction mode. Completely analytical solution for the continuous conduction mode is derived. Appropriate numerical methods are proposed to obtain the circuit waveforms in both of the operating modes, and to compute the performance parameters. Source code of the program that performs such computation is provided.

  7. 6 MeV RF Linac for cargo scanning and industrial radiography

    International Nuclear Information System (INIS)

    2017-01-01

    RF Linac-based X-ray sources are very widely used for cargo-scanning and industrial X-ray radiography applications. A 6 MeV on-axis coupled-cavity S-band RF linac has been designed, developed and tested successfully at Electron Beam Centre, Navi Mumbai. This facility falls under the purview of BARC Safety Council, which has conducted safety reviews and awarded regulatory clearances for the operation of the linac system. This paper outlines the salient features of the 6 MeV linac, its safety aspects and test results. A brief history of regulatory aspects is also presented

  8. Drift tubes of Linac 2

    CERN Multimedia

    Photographic Service

    1977-01-01

    Being redied for installation, those at the right are for tank 1, those on the left for tank 2. Contrary to Linac 1, which had drift-tubes supported on stems, here the tubes are suspended, for better mechanical stability.

  9. Installation of the Gbar LINAC

    CERN Multimedia

    Maximilien, Brice

    2017-01-01

    Installation of the GBAR linac in its shielding bunker. The electrons accelerated to 10 MeV toward a target will produce the positrons that are necessary to form anti hydrogen with the antiprotons coming from the ELENA decelerator.

  10. Commissioning plans for SSC linac

    International Nuclear Information System (INIS)

    Hurd, J.W.; Aprile, R.L.; Chang, C.R.; Crist, C.E.; Cutler, R.I.; Funk, L.W.; Guy, F.W.; Leifeste, G.T.; Raparia, D.; Saadatmand, K.; Sethi, R.C.; Swenson, D.A.; Tooker, J.; Yao, C.G.

    1992-01-01

    Presented are the general description of the SSC linac and the plans for commissioning. Sections of the linac are installed, tested, and beam commissioned in a serial approach. A specialized set of diagnostics is used to characterize the beam through each section. In addition to the standard diagnostic set, plans call for the use of a bunch shape monitor and x-ray spectrometer. Streak camera and digital imaging diagnostics will be developed. The commissioning plan is folded into the general linac project schedule to show the relation between delivery, staging, installation, conditioning, and actual commissioning with beam. These plans form the basis for coordination between the various organizations responsible for different elements of the linac including the technical components, infrastructure, and temporary staging and operation facilities. (Author) 2 figs., 17 refs

  11. Superconducting linacs used with tandems

    International Nuclear Information System (INIS)

    Ben-Zvi, I.

    1984-01-01

    The main features of superconducting linacs used as post-accelerators of tandems are reviewed. Various aspects of resonators, cryogenics and electronics are discussed, and recent advances in the field are presented. (orig.)

  12. SLAC Linac Preparations for FACET

    International Nuclear Information System (INIS)

    Erickson, Roger

    2011-01-01

    The SLAC 3km linear electron accelerator has been cut at the two-thirds point to provide beams to two independent programs. The last third provides the electron beam for the Linac Coherent Light Source (LCLS), leaving the first two-thirds available for FACET, the new experimental facility for accelerator science and test beams. In this paper, we describe this separation and projects to prepare the linac for the FACET experimental program.

  13. Comparison of LINAC-4 Designs

    CERN Document Server

    Crandall, K; Sargsyan, E; Lallement, J-B; CERN. Geneva. BE Department

    2009-01-01

    We have studied the expected performance of two drift tube linac (DTL) designs proposed for LINAC-4. The two designs use the same cell geometries but are characterized by different phase (φs) and accelerating field (E0) distributions. In addition we have investigated the expected performance of 3 different quadrupole focusing schemes in each design. The expected performance of these 6 variants is compared with respect to their stability and risk of beam loss with alignment errors.

  14. Inner structure of Linac 2

    CERN Multimedia

    CERN PhotoLab

    1977-01-01

    With the advent of the 800 MeV Booster in 1972, the original injector of the PS, a 50 MeV Alvarez-type proton linac, had reached its limits, in terms of intensity and stability. In 1973 one therefore decided to build a new linac (Linac 2), also with a drift-tube Alvarez structure and an energy of 50 MeV. It had a new Cockcroft-Walton preinjector with 750 keV, instead of the previous one with 500 keV. Linac 2 was put into service in 1980. The old Linac 1 was then used for the study of, and later operation with, various types of ions. This picture shows the inner structure of Linac 2, with drift-tubes hanging on stems under a rigid support structure, soon to be mounted inside tank 1 (750 keV to 10 MeV, the lowest-energy one of 3). Frank Malthouse is standing in the background.

  15. Testing begins on Linac4

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    On 3 August 2012, the Linac4 radiofrequency quadrupole (RFQ) module was installed at the accelerator test-stand in Building 152. The site will be the module’s home for almost a year, as the linear accelerator enters the assembly and testing stage.   Final module assembly is carried out before installation in Building 152.  Over the next Long Shutdown (LS2), Linac4 will replace the current Linac2 linear accelerator as the first link in CERN’s accelerator chain. It will deliver particles at 160 MeV to the PS Booster, more than triple the energy currently delivered by Linac2. But before the accelerator team can pop the champagne, the various elements of Linac4 will be tested and re-tested in facilities across CERN. “The first Linac4 tests are currently underway, starting with the CERN-built RFQ,” says Carlo Rossi, a physicist in the RF Group of the Beams (BE) Department and the RFQ project coordinator. “It’s an extremely impre...

  16. H- ion sources for CERN's Linac4

    Science.gov (United States)

    Lettry, J.; Aguglia, D.; Coutron, Y.; Chaudet, E.; Dallocchio, A.; Gil Flores, J.; Hansen, J.; Mahner, E.; Mathot, S.; Mattei, S.; Midttun, O.; Moyret, P.; Nisbet, D.; O'Neil, M.; Paoluzzi, M.; Pasquino, C.; Pereira, H.; Arias, J. Sanchez; Schmitzer, C.; Scrivens, R.; Steyaert, D.

    2013-02-01

    The specifications set to the Linac4 ion source are: H- ion pulses of 0.5 ms duration, 80 mA intensity and 45 keV energy within a normalized emittance of 0.25 mmmrad RMS at a repetition rate of 2 Hz. In 2010, during the commissioning of a prototype based on H- production from the plasma volume, it was observed that the powerful co-extracted electron beam inherent to this type of ion source could destroy its electron beam dump well before reaching nominal parameters. However, the same source was able to provide 80 mA of protons mixed with a small fraction of H2+ and H3+ molecular ions. The commissioning of the radio frequency quadrupole accelerator (RFQ), beam chopper and H- beam diagnostics of the Linac4 are scheduled for 2012 and its final installation in the underground building is to start in 2013. Therefore, a crash program was launched in 2010 and reviewed in 2011 aiming at keeping the original Linac4 schedule with the following deliverables: Design and production of a volume ion source prototype suitable for 20-30 mA H- and 80 mA proton pulses at 45 keV by mid-2012. This first prototype will be dedicated to the commissioning of the low energy components of the Linac4. Design and production of a second prototype suitable for 40-50 mA H- based on an external RF solenoid plasma heating and cesiated-surface production mechanism in 2013 and a third prototype based on BNL's Magnetron aiming at reliable 2 Hz and 80 mA H- operations in 2014. In order to ease the future maintenance and allow operation with Ion sources based on three different production principles, an ion source "front end" providing alignment features, pulsed gas injection, pumping units, beam tuning capabilities and pulsed bipolar high voltage acceleration was designed and is being produced. This paper describes the progress of the Linac4 ion source program, the design of the Front end and first ion source prototype. Preliminary results of the summer 2012 commissioning are presented. The outlook on

  17. Detuning effect in a traveling wave type linac

    International Nuclear Information System (INIS)

    Arai, Shigeaki.

    1981-10-01

    Detailed measurement of acceleration characteristics has been performed on a 15 MeV electron linac as the injector of the electron synchrotron at Institute for Nuclear Study, University of Tokyo. Remarkable feature of the results is that the energy gain as well as the energy spread of the output beam, are optimized when the linac is operated with the microwave whose frequency is higher than the resonant frequency of the accelerator waveguide. The difference of this operating frequency from the resonant frequency grows up as the beam intensity is increased, and amounts to 250 KHz when the beam intensity is 350 mA. In order to clarify the mechanism of the phenomena, the interaction of electron beam with the microwave in the accelerator structure of traveling wave type, is examined on the linac and also on a test accelerator structure. For the analysis of the experimental results, the normal mode method which has been used for standing wave cavities, is developed so as to be applied to the accelerator structure of traveling wave type. The results of analysis show that the observed phenomena at INS linac are caused by the resonant frequency shift, detuning, due to the reactive beam loading and this detuning effects are compensated by use of the microwave of higher frequency. Thus the detuning effects are significant even in the traveling wave type linac composed of buncher and regular sections as well as in the standing wave type accelerator structure. (author)

  18. Configuring the SLC linac for injection into PEP

    International Nuclear Information System (INIS)

    Bane, K.L.F.

    1989-01-01

    From time to time the normal SLC physics program is to be interrupted so that beam can be delivered to PEP. In order that the switch to PEP injection (and the switch back again) can be accomplished quickly and easily, the gun, the damping rings, the linac phase ramp, the energy profile of the linac klystrons for the scavenger bunch, and the entire positron production system are to be kept the same as in the SLC configuration. What mainly remains to be changed is the linac klystron profile for the leading two bunches - those going to PEP. The new klystron profile must be such that it leaves these two beams (1) with final energies that match that of the storage ring and (2) with final energy spectra that fit within the energy aperture of the PEP transfer line. The conditions that need to be met in order to achieve these two goals are discussed in this note. 1 ref., 2 figs

  19. Systematic study on the tunneling conductance in a normal-metal/px+y ± ipy-x-wave superconductor junction

    International Nuclear Information System (INIS)

    Jin Biao; Zhang Yinhan; Cheng Qiang

    2010-01-01

    The chiral p x+y ± ip y-x -wave state is currently considered to be a promising candidate state for Sr 2 RuO 4 in the light of microscopic theories. We theoretically investigate the tunneling conductance in a normal-metal/p x+y ± ip y-x -wave superconductor junction over a wide range of temperature and barrier strength. For a cylindrical Fermi surface with the magnitude of the radius R, the p x+y ± ip y-x -wave gap function exhibits two typical types of nodal structures when R = 1.0 and R=1/√2, respectively. It is found, in particular, that the line shapes of the conductance spectra for R∼1/√2 cases can qualitatively account for the existing in-plane tunneling experiments on Sr 2 RuO 4 .

  20. Simultaneous identification of a contaminant source and hydraulic conductivity via the restart normal-score ensemble Kalman filter

    Science.gov (United States)

    Xu, Teng; Gómez-Hernández, J. Jaime

    2018-02-01

    Detecting where and when a contaminant entered an aquifer from observations downgradient of the source is a difficult task; this identification becomes more challenging when the uncertainty about the spatial distribution of hydraulic conductivity is accounted for. In this paper, we have implemented an application of the restart normal-score ensemble Kalman filter (NS-EnKF) for the simultaneous identification of a contaminant source and the spatially variable hydraulic conductivity in an aquifer. The method is capable of providing estimates of the spatial location, initial release time, the duration of the release and the mass load of a point-contamination event, plus the spatial distribution of hydraulic conductivity together with an assessment of the estimation uncertainty of all the parameters. The method has been applied in synthetic aquifers exhibiting both Gaussian and non-Gaussian patterns. The identification is made possible by assimilating in time both piezometric head and concentration observations from an array of observation wells. The method is demonstrated in three different synthetic scenarios that combine hydraulic conductivities with unimodal and bimodal histograms, and releases in high and low conductivity zones. The results prove that the specific implementation of the EnKF is capable of recovering the source parameters with some uncertainty and of recovering the main patterns of heterogeneity of the hydraulic conductivity fields by assimilating a sufficient number of state variable observations. The proposed approach is an important step towards contaminant source identification in real aquifers, which may have logconductivity spatial distributions with either Gaussian or non-Gaussian features, yet, it is still far from practical applications since the transport parameters, the external sinks and sources and the initial and boundary conditions are assumed known.

  1. Superconducting LINAC booster for the Mumbai pelletron

    Indian Academy of Sciences (India)

    LINAC), to boost the energy of heavy ion beams from the 14UD Pelletron accelerator, at Tata Institute of Fundamental Research, Mumbai. The accelerating structures in the LINAC are quarter wave resonators (QWR) coated with lead which is ...

  2. Design of an L-band normally conducting RF gun cavity for high peak and average RF power

    Energy Technology Data Exchange (ETDEWEB)

    Paramonov, V., E-mail: paramono@inr.ru [Institute for Nuclear Research of Russian Academy of Sciences, 60-th October Anniversary prospect 7a, 117312 Moscow (Russian Federation); Philipp, S. [Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen (Germany); Rybakov, I.; Skassyrskaya, A. [Institute for Nuclear Research of Russian Academy of Sciences, 60-th October Anniversary prospect 7a, 117312 Moscow (Russian Federation); Stephan, F. [Deutsches Elektronen-Synchrotron DESY, Platanenallee 6, D-15738 Zeuthen (Germany)

    2017-05-11

    To provide high quality electron bunches for linear accelerators used in free electron lasers and particle colliders, RF gun cavities operate with extreme electric fields, resulting in a high pulsed RF power. The main L-band superconducting linacs of such facilities also require a long RF pulse length, resulting in a high average dissipated RF power in the gun cavity. The newly developed cavity based on the proven advantages of the existing DESY RF gun cavities, underwent significant changes. The shape of the cells is optimized to reduce the maximal surface electric field and RF loss power. Furthermore, the cavity is equipped with an RF probe to measure the field amplitude and phase. The elaborated cooling circuit design results in a lower temperature rise on the cavity RF surface and permits higher dissipated RF power. The paper presents the main solutions and results of the cavity design.

  3. Upgrading the Fermilab Linac local control system

    International Nuclear Information System (INIS)

    McCrory, E.S.; Goodwin, R.W.; Shea, M.F.

    1991-02-01

    A new control system for the Fermilab Linac is being designed, built and implemented. First, the nine-year-old linac control system is being replaced. Second, a control system for the new 805 MHz part of the linac is being built. The two systems are essentially identical, so that when the installations are complete, we will still have a single Linac Control System. 8 refs., 5 figs

  4. Electron Linacs for High Energy Physics

    International Nuclear Information System (INIS)

    Wilson, Perry B.

    2011-01-01

    The purpose of this article is to introduce some of the basic physical principles underlying the operation of electron linear accelerators (electron linacs). Electron linacs have applications ranging from linacs with an energy of a few MeV, such that the electrons are approximately relativistic, to future electron-positron linear colliders having a collision energy in the several-TeV energy range. For the most part, only the main accelerating linac is treated in this article.

  5. Status and performance of PF injector linac

    International Nuclear Information System (INIS)

    Sato, Isamu

    1994-01-01

    PF injector linac has been improved on a buncher section for accelerating of intense electron beam, and reinforced a focusing system of the positron generator linac for the expansion of phase space. In this presentation, I shall report present status and performance of PF injector linac, and discuss its upgrade program for B-factory project. (author)

  6. Radiotechnical Institute activity in the linac field

    International Nuclear Information System (INIS)

    Murin, B.P.

    1976-01-01

    For many years, the Radiotechnical Institute has been involved in a number of projects aimed at constructing linear accelerators for protons or electrons. This report summarizes the experience gained and covers 1) some problems of developing linacs to serve as meson or neutron generators, 2) results of study of a linac with asymmetric alternating phase focusing, and 3) electron linac projects. (author)

  7. IMPACT simulation and the SNS linac beam

    International Nuclear Information System (INIS)

    Zhang, Y.; Qiang, J.

    2008-01-01

    Multi-particle tracking simulations for the SNS linac beam dynamics studies are performed with the IMPACT code. Beam measurement results are compared with the computer simulations, including beam longitudinal halo and beam losses in the superconducting linac, transverse beam Courant-Snyder parameters and the longitudinal beam emittance in the linac. In most cases, the simulations show good agreement with the measured results

  8. The normalization of data in the Constant-Murley score for the shoulder. A study conducted on 563 healthy subjects.

    Science.gov (United States)

    Grassi, F A; Tajana, M S

    2003-01-01

    The study was conducted in order to evaluate the theoretical design of the Constant-Murley system and to reveal any difficulties in obtaining data when it is used in 563 subjects not affected with shoulder pathology. The total mean score for the subjects examined was 85.2 points (minimum 75, maximum 100 points). Values revealed a decreasing trend beginning at 50 years of age for men and 30 for women. Only 4 subjects achieved a maximum score of 100. The measurements taken allowed us to elaborate a reference table based on sex and age, which was required to calculate the correct score. These values differ from those reported by the inventors of the system and they reveal the need to compile personal tables for the normalization of scores.

  9. Light ion linacs for medical applications

    International Nuclear Information System (INIS)

    Bradbury, J.N.; Knapp, E.A.; Nagle, D.E.

    1975-01-01

    Recent advances in linear accelerator technology point to the feasibility of designing and developing practical medical linacs for producing protons, neutrons, or π mesons for the radiation therapy of cancer. Additional uses of such linacs could include radioisotope production and charged particle radiography. For widespread utilization medical linacs must exhibit reasonable cost, compactness, reliability, and simplicity of operation. Possible extensions of current accelerator technology which might provide these characteristics are discussed in connection with linac design, fabrication techniques, materials, power sources, injectors, and particle collection and delivery systems. Parameters for a medical proton linac for producing pions are listed. (U.S.)

  10. Drift Tube Linac Conditioning of Tank1

    CERN Document Server

    Shafqat, N; Toor, W A

    2014-01-01

    Tank1 of the Drift Tube Linac (DTL) of the Linac4 has been conditioned at the Linac4 tunnel. The tank was tuned for resonance at 352.2 MHz, and stable operation has been achieved with 725 µs long RF pulses at a repetition rate of 1 Hz. The maximum RF level that has been reached is 810 kW with a pulse width of 600 µs. Since this was the first RF structure exclusively conditioned in the Linac4 tunnel with the operation and control software of Linac4, some related issues and limitations had to be taken into account.

  11. Heavy-ion superconducting linacs

    International Nuclear Information System (INIS)

    Delayen, J.R.

    1989-01-01

    This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs

  12. Heavy-ion superconducting linacs

    Energy Technology Data Exchange (ETDEWEB)

    Delayen, J.R.

    1989-01-01

    This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs.

  13. Emittance growth in rf linacs

    International Nuclear Information System (INIS)

    Jameson, R.A.

    1979-01-01

    As the space-charge limit is approached, the current that can be accelerated in an rf linac and the output emittance that can be expected are discussed. The role of the envelope equations to estimate limits is outlined. The results of numerical experiments to explore general properties of emittance growth are given

  14. The new Linac moves mountains

    CERN Multimedia

    2008-01-01

    The civil engineering work has started for Linac 4, one of the major renovation projects for the CERN accelerator complex. The work will be completed at the end of 2010 and the new linear accelerator is scheduled to be commissioned in 2013.

  15. Linac boosters for electrostatic machines

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Brookhaven National Lab., Upton, NY

    1990-01-01

    A survey of linacs which are used as boosters to electrostatic accelerators is presented. Machines both operating and under construction, copper and superconducting, are reviewed. The review includes data on the accelerating structures, performance, rf and control, beam optics, budget, vacuum and cryogenics. (orig.)

  16. Progress in design of the SNS linac

    International Nuclear Information System (INIS)

    Hardekopf, R.

    2001-01-01

    The Spallation Neutron Source (SNS) is a six-laboratory collaboration to build an intense pulsed neutron facility at Oak Ridge, TN. The linac design has evolved from the conceptual design presented in 1997 in order to achieve higher initial performance and to incorporate desirable upgrade features. The linac is now designed to produce 2-MW beam power using a combination of radio-frequency quadrupole (RFQ) linac, drift-tube linac (DTL), coupled-cavity linac (CCL), and superconducting-RF (SRF) linac. Designs of each of these elements support he high peak intensity and high quality beam required for injection into the SNS accumulator ring. This paper will trace the evolution of the linac design and the progress made in the R and D program. (author)

  17. Florida State University superconducting linac

    International Nuclear Information System (INIS)

    Myers, E.G.; Fox, J.D.; Frawley, A.D.; Allen, P.; Faragasso, J.; Smith, D.; Wright, L.

    1988-01-01

    As early as the fall of 1977 it was decided that the future research needs of their nuclear structure laboratory required an increase in energy capability to at least 8 MeV per nucleon for the lighter ions, and that these needs could be met by the installation of a 17 MV tandem Van de Graaff accelerator. The chief problem with this proposal was the high cost. It became apparent that a far less expensive option was to construct a linear accelerator to boost the energy from their existing 9 MV tandem. The options open to them among linac boosters were well represented by the room temperature linac at Heidelberg and the superconducting Stony Brook and Argonne systems. By the Spring of 1979 it had been decided that both capital cost and electric power requirements favored a superconducting system. As regards the two superconducting resonator technologies - the Argonne niobium-copper or the Caltech-Stony Brook lead plated copper - the Argonne resonators, though more expensive to construct, had the advantages of more boost per resonator, greater durability of the superconducting surface and less stringent beam bunching requirements. In 1980 pilot funding from the State of Florida enabled the construction of a building addition to house the linac and a new target area, and the setting up of a small, three resonator, test booster. Major funding by the NSF for the laboratory upgrade started in 1984. With these funds they purchased their present helium liquefaction and transfer system and constructed three large cryostats, each housing four Argonne beta = 0.105 resonators and two superconducting solenoids. The last large cryostat was completed and installed on-line early this year and the linac was dedicated on March 20. Nuclear physics experiments using the whole linac began in early June. 4 references, 6 figures, 1 table

  18. Accelerating Convergence in Molecular Dynamics Simulations of Solutes in Lipid Membranes by Conducting a Random Walk along the Bilayer Normal.

    Science.gov (United States)

    Neale, Chris; Madill, Chris; Rauscher, Sarah; Pomès, Régis

    2013-08-13

    All molecular dynamics simulations are susceptible to sampling errors, which degrade the accuracy and precision of observed values. The statistical convergence of simulations containing atomistic lipid bilayers is limited by the slow relaxation of the lipid phase, which can exceed hundreds of nanoseconds. These long conformational autocorrelation times are exacerbated in the presence of charged solutes, which can induce significant distortions of the bilayer structure. Such long relaxation times represent hidden barriers that induce systematic sampling errors in simulations of solute insertion. To identify optimal methods for enhancing sampling efficiency, we quantitatively evaluate convergence rates using generalized ensemble sampling algorithms in calculations of the potential of mean force for the insertion of the ionic side chain analog of arginine in a lipid bilayer. Umbrella sampling (US) is used to restrain solute insertion depth along the bilayer normal, the order parameter commonly used in simulations of molecular solutes in lipid bilayers. When US simulations are modified to conduct random walks along the bilayer normal using a Hamiltonian exchange algorithm, systematic sampling errors are eliminated more rapidly and the rate of statistical convergence of the standard free energy of binding of the solute to the lipid bilayer is increased 3-fold. We compute the ratio of the replica flux transmitted across a defined region of the order parameter to the replica flux that entered that region in Hamiltonian exchange simulations. We show that this quantity, the transmission factor, identifies sampling barriers in degrees of freedom orthogonal to the order parameter. The transmission factor is used to estimate the depth-dependent conformational autocorrelation times of the simulation system, some of which exceed the simulation time, and thereby identify solute insertion depths that are prone to systematic sampling errors and estimate the lower bound of the

  19. first tank of Linac 1

    CERN Multimedia

    This was the first tank of the linear accelerator Linac1, the injection system for the Proton Synchrotron, It ran for 34 years (1958 - 1992). Protons entered at the far end and were accelerated between the copper drift tubes by an oscillating electromagnetic field. The field flipped 200 million times a second (200 MHz) so the protons spent 5 nanoseconds crossing a drift tube and a gap. Moving down the tank, the tubes and gaps had to get longer as the protons gained speed. The tank accelerated protons from 500 KeV to 10 MeV. Linac1 was also used to accelerate deutrons and alpha particles for the Intersecting Storage Rings and oxygen and sulpher ions for the Super Proton Synchrotron heavy ion programme.

  20. Review of induction linac studies

    International Nuclear Information System (INIS)

    Keefe, Denis

    1984-01-01

    The major emphasis of the U.S. program in Heavy Ion Fusion Accelerator Research is on developing and understanding induction-linac systems that employ multiple beams of high-current heavy ions. The culmination of the plan lies in building the High Temperature Experiment (HTE) which will involve an ion induction linac to deliver multiple high current beams, that can be focussed and overlapped on a two-millimeter diameter spot. A sequence of three major experimental activities are as follows. In the Single-Beam Transport Experiment (SBTE), the stability or otherwise transport of a high-current Cs +1 beam over a long distance is tested. In the Multiple-Beam Experiment (MBE), the experiment is designed to simulate on a small scale as many as possible of the features to be encountered in the HTE. (Mori, K.)

  1. The BATES linac control system

    International Nuclear Information System (INIS)

    Russ, T.; Radouch, Z.

    1989-01-01

    The Bates linac control system (LCS), a distributed processing architecture, is described. Due to the historic evolution of the system, a mix of different hardware, operating systems and programming languages are used throughout. However, a standardized interface at the network level enables a smooth system integration. In particular, a multicasting scheme for data transmission over the network permits simultaneous database updates on more than one workstation. This allows for true distribution of data processing power. 3 figs

  2. LFSC - Linac Feedback Simulation Code

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Valentin; /Fermilab

    2008-05-01

    The computer program LFSC (<Linac Feedback Simulation Code>) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100 Hz, as slower feedbacks, operating in the 0.1-1 Hz range in the Main Linac and Beam Delivery System. The code LFSC is running under Matlab for MS Windows operating system. It contains about 30,000 lines of source code in more than 260 subroutines. The code uses the LIAR ('Linear Accelerator Research code') for particle tracking under ground motion and technical noise perturbations. It uses the Guinea Pig code to simulate the luminosity performance. A set of input files includes the lattice description (XSIF format), and plane text files with numerical parameters, wake fields, ground motion data etc. The Matlab environment provides a flexible system for graphical output.

  3. Wakefields in SLAC linac collimators

    Directory of Open Access Journals (Sweden)

    A. Novokhatski

    2014-12-01

    Full Text Available When a beam travels near collimator jaws, it gets an energy loss and a transverse kick due to the backreaction of the beam field diffracted from the jaws. The effect becomes very important for an intense short bunch when a tight collimation of the background beam halo is required. In the Linac Coherent Light Source at SLAC a collimation system is used to protect the undulators from radiation due to particles in the beam halo. The halo is most likely formed from gun dark current or dark current in some of the accelerating sections. However, collimators are also responsible for the generation of wake fields. The wake field effect from the collimators not only brings an additional energy jitter and change in the trajectory of the beam, but it also rotates the beam on the phase plane, which consequently leads to a degradation of the performance of the Free Electron Laser at the Linac Coherent Light Source. In this paper, we describe a model of the wake field radiation in the SLAC linac collimators. We use the results of a numerical simulation to illustrate the model. Based on the model, we derive simple formulas for the bunch energy loss and the average kick. We also present results from experimental measurements that confirm our model.

  4. Linacs for medical and industrial applications

    International Nuclear Information System (INIS)

    Hamm, R.W.

    1986-01-01

    Linear accelerators for medical and industrial applications have become an important commercial business. Microwave electron linacs for cancer radiation therapy and high-energy industrial radiography form the bulk of this market, but these, as well as induction linacs, are now being offered for radiation processing applications such as sterilization of disposable medical products, food preservation and material modifications. The radio frequency quadrupole (RFQ) linac has now made the ion linac also practical for commercial applications in medicine and industry, including radiation therapy, isotope production, neutron production, materials modification, and energy transfer processes. Ion linacs for several of these applications will soon be commercially available. The market for both ion and electron linacs is expected to significantly grow in several exciting and important areas

  5. Conceptual Design of the Linac4 Main Dump

    CERN Document Server

    Leitao, I V; Maglioni, C

    2012-01-01

    Linac4 is the new CERN linear accelerator intended to replace the ageing Linac2 as the injector to the Proton Synchrotron Booster (PSB) for increasing the luminosity of the Large Hadron Collider (LHC). By delivering a 160MeV H- beam, Linac4 will provide the necessary conditions to double the brightness and intensity of the beam extracted from the PSB. This paper describes the conceptual design of the Linac4 Main Dump, where two different concepts relying respectively on water and air cooling were compared and evaluated. Based on the application of analytical models for the energy deposited by the beam, heat conduction and cooling concepts, a parametric study was performed. This approach allowed the identification of the “optimal” configuration for these two conceptual geometries and their relative comparison. Besides giving the theoretical guidelines for the design of the new dump, this work also contributes to the development of analytical tools to allow a better understanding of the influence of the se...

  6. Laser plasma LINAC

    International Nuclear Information System (INIS)

    Palmer, R.B.; Baggett, N.; Claus, J.; Fernow, R.; Ghosh, A.; Giordano, S.; Radeka, V.; Stumer, I.; Takacs, P.; Warren, J.

    1985-01-01

    The grating accelerator concept is reviewed. The use of a double row of conducting droplets instead of a conventional grating constrains the fields to a narrow band. The use of droplets also allows fields that will destroy the structure. RF modelling results are presented together with a simple theory of the fields. Coupling to incoming radiation is described. A possible laser specification is also given. (orig.)

  7. Laser plasma LINAC

    International Nuclear Information System (INIS)

    Palmer, R.B.; Baggett, N.; Claus, J.

    1984-01-01

    The grating accelerator concept is reviewed. The use of a double row of conducting droplets instead of a conventional grating constrains the fields to a narrow band. The use of droplets also allows fields that will destroy the structure. The rf modeling results are presented together with a simple theory of the fields. Coupling to incoming radiation is described. A possible laser specification is also given. 9 references, 8 figures

  8. Heavy-ion-linac post-accelerators

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1979-01-01

    The main features of the tandem-linac system for heavy-ion acceleration are reviewed and illustrated in terms of the technology and performance of the superconducting heavy-ion energy booster at Argonne. This technology is compared briefly with the corresponding technologies of the superconducting linac at Stony Brook and the room-temperature linac at Heidelberg. The performance possibilities for the near-term future are illustrated in terms of the proposed extension of the Argonne booster to form ATLAS

  9. Diagnostic expert system in the PF LINAC

    International Nuclear Information System (INIS)

    Abe, Isamu; Nakahara, Kazuo; Kitamura, Masaharu.

    1992-01-01

    A prototype diagnostic expert system (ES) was developed for the Photon Factory 2.5-GeV electron/positron LINAC injector system. The ES has been on-lined with the conventional linac computer network for receiving real data. This project was undertaken in an attempt to reduce the linac operator's mental workload, diagnosis duties, and to explore Artificial Intelligence (AI) technologies. The outlook for ES and its problems, and what has been achieved are outlined in this presentation. (author)

  10. Muon Acceleration Concepts for NuMAX: "Dual-use" Linac and "Dogbone" RLA

    Science.gov (United States)

    Bogacz, S. A.

    2018-02-01

    We summarize the current state of a concept for muon acceleration aimed at a future Neutrino Factory. The main thrust of these studies was to reduce the overall cost while maintaining performance by exploring the interplay between the complexity of the cooling systems and the acceptance of the accelerator complex. To ensure adequate survival for the short-lived muons, acceleration must occur at high average gradient. The need for large transverse and longitudinal acceptances drives the design of the acceleration system to an initially low RF frequency, e.g., 325 MHz, which is then increased to 650 MHz as the transverse size shrinks with increasing energy. High-gradient normal conducting RF cavities at these frequencies require extremely high peak-power RF sources. Hence superconducting RF (SRF) cavities are chosen. We consider two cost effective schemes for accelerating muon beams for a stageable Neutrino Factory: exploration of the so-called "dual-use" linac concept, where the same linac structure is used for acceleration of both H- and muons and, alternatively, an SRF-efficient design based on a multi-pass (4.5) "dogbone" RLA, extendable to multi-pass FFAG-like arcs.

  11. Transverse and longitudinal emittance measurements in the ELSA linac

    International Nuclear Information System (INIS)

    Loulergue, A.; Dowell, D.H.; Joly, S.; De Brion, J.P.; Haouat, G.; Schumann, F.

    1997-01-01

    The ELSA RF linac photoinjector has been designed to deliver high-brightness electron beams. The present paper deals with the transverse and longitudinal emittance measurements, at different locations along the ELSA beam line, and the analysis of their variations as a function of the photoinjector parameters : magnetic field generated by the anode focusing lens, bunch charge and pulse duration. While transverse emittance has been already studied in other similar installations, there has been little study of the electron beam longitudinal dynamics. Experimental results are presented and compared to simulation-code expectations. For 2.0 nC, 85 A electron bunches, a normalized rms emittance of 2 π mm mrad and a brightness of 4.5 x 10 13 A/(π m rad) 2 at the linac exit have been measured as well as less than 10 keV rms energy spread (or less than 0.1% at 16.5 MeV). (orig.)

  12. Electron bunch structure in energy recovery linac with high-voltage dc photoelectron gun

    Directory of Open Access Journals (Sweden)

    Y. M. Saveliev

    2016-09-01

    Full Text Available The internal structure of electron bunches generated in an injector line with a dc photoelectron gun is investigated. Experiments were conducted on the ALICE (accelerators and lasers in combined experiments energy recovery linac at Daresbury Laboratory. At a relatively low dc gun voltage of 230 kV, the bunch normally consisted of two beamlets with different electron energies, as well as transverse and longitudinal characteristics. The beamlets are formed at the head and the tail of the bunch. At a higher gun voltage of 325 kV, the beam substructure is much less pronounced and could be observed only at nonoptimal injector settings. Experiments and computer simulations demonstrated that the bunch structure develops during the initial beam acceleration in the superconducting rf booster cavity and can be alleviated either by increasing the gun voltage to the highest possible level or by controlling the beam acceleration from the gun voltage in the first accelerating structure.

  13. Disruptive behavior in preschool children: distinguishing normal misbehavior from markers of current and later childhood conduct disorder.

    Science.gov (United States)

    Hong, Ji S; Tillman, Rebecca; Luby, Joan L

    2015-03-01

    To investigate which disruptive behaviors in preschool were normative and transient vs markers of conduct disorder, as well as which disruptive behaviors predicted the persistence of conduct disorder into school age. Data from a longitudinal study of preschool children were used to investigate disruptive behaviors. Caregivers of preschoolers ages 3.0-5.11 years (n = 273) were interviewed using the Preschool Age Psychiatric Assessment to derive the following diagnostic groups: conduct disorder, externalizing disorder without conduct disorder, internalizing disorder without externalizing disorder, and healthy. At school age, participants were again assessed via an age-appropriate diagnostic interview. Logistic and linear regression with pairwise group comparisons was used to investigate clinical markers of preschool conduct disorder and predictors of school age conduct disorder. Losing one's temper, low-intensity destruction of property, and low-intensity deceitfulness/stealing in the preschool period were found in both healthy and disordered groups. In contrast, high-intensity argument/defiant behavior, both low- and high-intensity aggression to people/animals, high-intensity destruction of property, high-intensity deceitfulness/stealing, and high-intensity peer problems were markers of preschool conduct disorder and predictors of school age conduct disorder. Inappropriate sexual behavior was not a marker for preschool conduct disorder but was a predictor of school age conduct disorder. These findings provide a guide for primary care clinicians to help identify preschoolers with clinical conduct disorder and those who are at risk for persistent conduct disorder in childhood. Preschoolers displaying these symptoms should be targeted for mental health assessment. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. DIFFERENCE IN THE INTENSITY OF DEPRESSION BETWEEN PARENTS HAVING CHILDREN WITH CONDUCT DISORDER AND PARENTS HAVING NORMAL CHILDREN

    OpenAIRE

    Bindu Meethale Veettil; Sheeba Damodar; Jayadevan Sreedharan; Vimal Rohan K; Jayasree Ananda Bhavan Kumaran

    2017-01-01

    BACKGROUND Parents experience psychological trauma if they recognise that their children are having conduct disorder, which is unacceptable to the society and against the social norms. The intensity of depression in parents having children with conduct disorder is included in this study. MATERIALS AND METHODS Exploratory research was used in this study as the method of study. A sample was selected from parents having children with conduct disorder reported in various psychia...

  15. Induction linacs as radiation processors

    International Nuclear Information System (INIS)

    Birx, D.L.

    1986-01-01

    Experiments at the Lawrence Livermore National Laboratory (LLNL), University of California, in conjunction with the University of California at Davis have shown induction linear accelerators (linacs) to be suitable for radiation processing of food. Here we describe how it might be possible to optimize this technology developded for the Department of Defense to serve in radiation processing. The possible advantages of accelerator-produced radiation over the use of radioisotopes include a tailor-made energy spectrum that can provide much deeper penetration and thereby better dose uniformity

  16. Signal multiplexing scheme for LINAC

    International Nuclear Information System (INIS)

    Sujo, C.I.; Mohan, Shyam; Joshi, Gopal; Singh, S.K.; Karande, Jitendra

    2004-01-01

    For the proper operation of the LINAC some signals, RF (radio frequency) as well as LF (low frequency) have to be available at the Master Control Station (MCS). These signals are needed to control, calibrate and characterize the RF fields in the resonators. This can be achieved by proper multiplexing of various signals locally and then routing the selected signals to the MCS. A multiplexing scheme has been designed and implemented, which will allow the signals from the selected cavity to the MCS. High isolation between channels and low insertion loss for a given signal are important issues while selecting the multiplexing scheme. (author)

  17. Induction linacs and pulsed power

    International Nuclear Information System (INIS)

    Caporaso, G.J.

    1995-01-01

    Progress in electronic power conversion technology is making possible a new class of induction linacs that can operate at extremely high repetition rates. Advances in insulator technology, pulse forming line design and switching may also lead to a new type of high current accelerator with accelerating gradients at least an order of magnitude greater than those attainable today. The evolution of the induction accelerator pulsed power system will be discussed along with some details of these emerging technologies which are at the frontiers of accelerator technology

  18. Study of characteristics of linac with TWRR

    International Nuclear Information System (INIS)

    Wang, Y.L.; Toyama, S.; Emoto, T.; Nomura, M.; Takahashi, N.; Oshita, H.; Hirano, K.; Sato, I.

    1994-01-01

    High power electron linac which is developed by PNC is an electron linac with the TWRR (Traveling Wave Resonant Ring). Some phenomena occurred on our high power test are mentioned. Some important characteristics such as stability and phase characteristic are discussed. (author)

  19. Fermilab Linac Upgrade Conceptual Design: Revision 3

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1989-07-01

    The goal of the Tevatron Collider Upgrade program is to improve the Collider luminosity and the fixed-target intensity. The Linac portion of this project will increase the energy of the existing 200- MeV linac to 400 MeV in order to reduce beam emittance degradation in the Booster.

  20. Present status of the ETL LINAC facility

    International Nuclear Information System (INIS)

    Suzuki, Ryoichi; Mikado, Tomohisa; Ohgaki, Hideaki

    1993-01-01

    The ETL LINAC has been operated for the beam injection to the storage rings NIJI-II, III, IV, and TERAS, and for the generation of an intense slow positron beam. The status of the ETL LINAC on the operations, the maintenances, and the improvements is described. (author)

  1. Linac design for the European spallation source

    Energy Technology Data Exchange (ETDEWEB)

    Klein, H. [Universitaet Postfach, Frankfurt am Main (Germany)

    1995-10-01

    A study group has started to develop a conceptual design for a European Spallation Source (ESS). This pulsed 5 MW source presently consists of a 1.334 GeV linac and two compressor rings. In the following mainly the high intensity linac part will be discussed, which has some features of interest for accelerators for transmutation of radioactive waste too.

  2. DESIGN AND FABRICATION OF THE BEAM POSITION MONITOR FOR THE PEFP LINAC

    Directory of Open Access Journals (Sweden)

    HYEOK-JUNG KWON

    2013-08-01

    Full Text Available The beam position monitor (BPM is an essential component for the PEFP 100-MeV linac's commissioning. A prototype stripline-type linac BPM was designed for this purpose. The electrode aperture is 20 mm in diameter, and the electrode is 25 mm long, so it can be installed between Drift Tube Linac (DTL101 and DTL102, which is the shortest distance. One end of the electrode is connected to the Sub Miniature Type A (SMA feed through for signal measurement, and the other end is terminated as a short. The signal amplitude of the fundamental component was calculated and compared with that of the second harmonic component. The designed BPM was fabricated and a low-power RF test was conducted. In this paper, the design, fabrication and low power test of the BPM for the PEFP linac are presented.

  3. High gradient linac for proton therapy

    Directory of Open Access Journals (Sweden)

    S. Benedetti

    2017-04-01

    Full Text Available Proposed for the first time almost 30 years ago, the research on radio frequency linacs for hadron therapy experienced a sparkling interest in the past decade. The different projects found a common ground on a relatively high rf operating frequency of 3 GHz, taking advantage of the availability of affordable and reliable commercial klystrons at this frequency. This article presents for the first time the design of a proton therapy linac, called TULIP all-linac, from the source up to 230 MeV. In the first part, we will review the rationale of linacs for hadron therapy. We then divided this paper in two main sections: first, we will discuss the rf design of the different accelerating structures that compose TULIP; second, we will present the beam dynamics design of the different linac sections.

  4. Superconducting heavy-ion linac at Argonne

    International Nuclear Information System (INIS)

    Aron, J.; Benaroya, R.; Bollinger, L.M.; Clifft, B.G.; Johnson, K.W.; Nixon, J.M.; Markovich, P.; Pardo, R.C.; Shepard, K.W.

    1981-01-01

    The design, status, and performance of the first operating superconducting heavy-ion accelerator, a linac used to boost the energies of beams from a 9-MV tandem, is summarized. When completed in 1981, the linac will consist of 24 independently-phased split-ring niobium resonators operating at 97 MHz. This linac is designed to provide 29 MV of acceleration. Because of the modular character of the system, the linac has been operable and useful since mid-1978, when a beam was accelerated through 2 units and the first nuclear-physics experiments were preformed. Now, 16 resonators are in use, and a beam has been accelerated for approx. 6000 h. Resonator performance has been remarkably stable, in spite of vacuum accidents, and the linac as a whole operates reliably without operators in attendance during nights and weekends. The ease and speed with which the beam energy can be changed is proving to be unexpectedly valuable to users

  5. LFSC - Linac Feedback Simulation Code

    International Nuclear Information System (INIS)

    Ivanov, Valentin; Fermilab

    2008-01-01

    The computer program LFSC ( ) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100 Hz, as slower feedbacks, operating in the 0.1-1 Hz range in the Main Linac and Beam Delivery System. The code LFSC is running under Matlab for MS Windows operating system. It contains about 30,000 lines of source code in more than 260 subroutines. The code uses the LIAR ('Linear Accelerator Research code') for particle tracking under ground motion and technical noise perturbations. It uses the Guinea Pig code to simulate the luminosity performance. A set of input files includes the lattice description (XSIF format), and plane text files with numerical parameters, wake fields, ground motion data etc. The Matlab environment provides a flexible system for graphical output

  6. Sustainable business conduct as business model or business identity : a stakeholder review of a potential trend towards a new normal

    OpenAIRE

    Kvarnström, Lovisa

    2016-01-01

    The objective of the thesis is to analyse how stakeholder influence has transformed sustainability work from being primarily risk management into becoming an integral part of business conduct and even business identities of today. To detect this trend I gather theoretical information that elaborate on the meaning and drivers of sustainable business conduct, sustainability as corporate identity, relevant stakeholders and ways of communicating to stakeholders. A case study of Ben & Jerry’s ...

  7. One-dimensional time-dependent conduction states and temperature distribution along a normal zone during a quench

    International Nuclear Information System (INIS)

    Lopez, G.

    1991-01-01

    The quench simulations of a superconducting (s.c.) magnet requires some assumptions about the evolution of the normal zone and its temperature profile. The axial evolution of the normal zone is considered through the longitudinal quench velocity. However, the transversal quench propagation may be considered through the transversal quench velocity or with the turn-to-turn time delay quench propagation. The temperature distribution has been assumed adiabatic-like or cosine-like in two different computer programs. Although both profiles are different, they bring about more or less the same qualitative quench results differing only in about 8%. Unfortunately, there are not experimental data for the temperature profile along the conductor in a quench event to have a realistic comparison. Little attention has received the temperature profile, mainly because it is not so critical parameter in the quench analysis. Nonetheless, a confident quench analysis requires that the temperature distribution along the normal zone be taken into account with good approximation. In this paper, an analytical study is made about the temperature profile

  8. H- Ion Sources For CERN’s Linac4

    CERN Document Server

    Lettry, J; Coutron, Y; Chaudeta, E; Dallocchio, A; Gil Flores, J; Hansen, J; Mahner, E; Mathot, S; Mattei, S; Midttun, O; Moyret, P; Nisbet, D; O’Neil, M; Paoluzzi, M; Pasquino, C; Pereira, H; Sanchez Arias, J; Schmitzer, C; Scrivens, R; Steyaert, D

    2013-01-01

    The specifications set to the Linac4 ion source are: H- ion pulses of 0.5 ms duration, 80 mA intensity and 45 keV energy within a normalized emittance of 0.25 mmmrad RMS at a repetition rate of 2 Hz. In 2010, during the commissioning of a prototype based on H- production from the plasma volume, it was observed that the powerful co-extracted electron beam inherent to this type of ion source could destroy its electron beam dump well before reaching nominal parameters. However, the same source was able to provide 80 mA of protons mixed with a small fraction of H2+ and H3+ molecular ions. The commissioning of the radio frequency quadrupole accelerator (RFQ), beam chopper and H- beam diagnostics of the Linac4 are scheduled for 2012 and its final installation in the underground building is to start in 2013. Therefore, a crash program was launched in 2010 and reviewed in 2011 aiming at keeping the original Linac4 schedule with the following deliverables: Design and production of a volume ion source prototype suitabl...

  9. 25th anniversary for Linac-2

    CERN Multimedia

    2003-01-01

    On Friday, 3 October 2003, the Linac team celebrated a quarter century of successful operation of one of its linear accelerators: Linac-2, the proton workhorse of the CERN accelerator complex. Linac-2, CERN's linear proton accelerator, has now been running for 25 years - ample reason for a small celebration. About 30 members of the original team (10 of the initially more than 50 are still working at CERN), and other CERN personnel met on 3 October 2003. Linac-2 is the first link in the accelerator chain Linac-2 - PS Booster - PS - SPS and eventually LHC. Beams from Linac-2 are used after further acceleration in the CERN complex for SPS fixed target physics; for antiproton production for the Antiproton Decelerator (AD); for test beams in the East Experimental Hall and in the PS; for nuclear physics at ISOLDE; for LHC test beams and in the past for both ISR physics and Antiproton production (AA/AC) and test beams in LEAR. Linac-2 was built to obtain higher intensities and better stability than with ...

  10. Beam position monitoring in the AGS Linac to Booster transfer line

    International Nuclear Information System (INIS)

    Shea, T.J.; Brodowski, J.; Witkover, R.

    1991-01-01

    A beam position monitor system has been developed and used in the commissioning of Brookhaven's Linac to Booster transfer line. This line transports a chopped, RF modulated H- beam from the 200 MeV Linac to the AGS Booster. Over a 15dB dynamic range in beam current, the position monitor system provides a real-time, normalized position signal with an analog bandwidth of about 20 MHz. Seven directional coupler style pickups are installed in the line with each pickup sensing both horizontal and vertical position. Analog processing electronics are located in the tunnel and incorporate the amplitude modulation to phase modulation normalization technique. To avoid interference from the 200 MHz linac RF system, processing is performed at 400 MHz. This paper provides a system overview and report results from the commissioning experience

  11. Radiation protection studies for a high-power 160 MeV proton linac

    CERN Document Server

    Mauro, Egidio

    2009-01-01

    CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H− linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS Booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This work summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, to estimate the radiological impact of ...

  12. submitter Radiation Protection Studies for CERN LINAC4/SPL Accelerator Complex

    CERN Document Server

    Mauro, Egidio; Silari, Marco

    2009-01-01

    CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H$^-$ linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This thesis summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed 1) to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, 2) to estimate the radiological i...

  13. Study on design of proton linacs

    International Nuclear Information System (INIS)

    Yu Qingchang

    2000-01-01

    Two important directions in the development of proton linacs are high-current proton linacs (mainly applied in nuclear power field) and compact proton linacs (for proton therapy). There are some common characteristics in them: (1) Employment of the novel accelerating structures, which are combination and evolution of the conventional ones; (2) Accelerating beam with small emittance; (3) Requirement for high reliability. The construction of the former is, however, much more difficult because it still needs low beam lose rate and as high power transformation efficiency as possible. Some important problems in the design of these accelerators are discussed and some schemes designed are presented

  14. Wire alignment system for ATF LINAC

    International Nuclear Information System (INIS)

    Hayano, H.; Takeda, S.; Matsumoto, H.; Matsui, T.

    1994-01-01

    A wire based alignment system is adopted to make less than 40μm precision alignment for injector linac of Accelerator Test Facility (ATF). The system consists of two stretched SUS wires, pickup coils and active mover stages. The position of pickup coils in a mount which will be installed into LINAC stages is set to the calculated wire position prior to installation. All of LINAC stages are then moved to keep the calculated position by the active mover. The test results of wire position detection in a long term are described. (author)

  15. Overview of the Pelletron Linac facility, Mumbai

    International Nuclear Information System (INIS)

    Pillay, R.G.

    2011-01-01

    The Pelletron LINAC Facility at TIFR, Mumbai, comprising the 14 MV Pelletron and the superconducting LINAC booster caters to a variety of experiments in basic and applied Sciences. The Liquid Helium Refrigeration plant for the LINAC has been upgraded to enhance the refrigeration capacity. New instrumentation and interface for control and monitor of the cryogenic parameters, beam diagnostics and beam transport devices have been developed and installed. Digital implementation of the LLRF control has been demonstrated. All seven beam lines in new user halls have been commissioned and several new experimental setups have been added. (author)

  16. The superconducting linac booster at the ANU

    International Nuclear Information System (INIS)

    Weisser, D.C.

    1995-02-01

    This report outlines the progress of the installation of the superconducting Linac booster at the Australian National University. The Linac is based upon four modules, three of which contain three split-loop resonators. The fourth cryostat was intended to be a superbuncher and so houses only one resonator. The first stage of Linac operation will employ only three modules with 2 MV/m from each resonator. It is expected that the implementation of all nine modules, in subsequent stages, would boost beams by 18 MV/q. The project has fostered productive international collaboration between UK and Australian scientists. 1 tab., 6 figs

  17. Operating experience with the ALS linac

    International Nuclear Information System (INIS)

    Selph, F.; Massoletti, D.

    1991-05-01

    The linac injector for the Advanced Light Source (ALS) at LBL was recently put into operation. Energy is 50 MeV, frequency 3 GHz. The electron gun delivers up to 6nC in a 3.0-ns bunch at 120 kV. A train of bunches is injected into a 1-Hz booster and accelerated to 1.5 GHz for storage ring injection. A magnetic analysis system is used for optimizing the linac. Measured beam properties from the gun and after acceleration in the linac are described. 9 refs., 3 figs

  18. Upgrade of the AGS H- linac

    International Nuclear Information System (INIS)

    Alessi, J.G.; Buxton, W.; Kponou, A.; LoDestro, V.; Mapes, M.; McNerney, A.J.; Raparia, D.

    1994-01-01

    The AGS linac presently accelerates 25 mA of H - to 200 MeV at a 5 Hz rep-rate and 500 μs pulse width. The Booster takes 4 pulses every 3.8 seconds, and the remaining pulses are used for isotope production. The authors are in the process of upgrading the linac to increase the average current delivered for isotope production by more than a factor of two, while at the same time expecting to decrease linac downtime. Various aspects of this upgrade are discussed, including the upgrade of the control system, new high power transmission line, transport line vacuum, and rf power supply system upgrades

  19. The Mothering of Conduct Problem and Normal Children in Spain and the USA: Authoritarian and Permissive Asynchrony

    OpenAIRE

    Cerezo Jiménez, María Ángeles; Wahler, Robert G.

    2005-01-01

    Ninety-two clinic-referred and nonclinical mother-child dyads in Spain and the USA were observed in their home settings under naturalistic conditions for a total of 477 hours. Children in the clinic-referred dyads were considered troubled because of conduct problems. The observations were aimed at assessing two forms of mother-child asynchrony, either of which was expected to differentiate clinic referred from nonclinical dyads. Authoritarian asynchrony was defined as a mother’s indiscriminat...

  20. Laser-driven grating linac

    International Nuclear Information System (INIS)

    Palmer, R.B.

    1982-01-01

    I would like to consider a 50 TeV on 50 TeV collider. Even a hadron machine with such an energy seems unrealistic with current technology. Magnetic fields higher than 10 Tesla are difficult and at this field the circumference would be 120 km. I conclude that only a high gradient Linac could be practical and that one should aim for 10 GeV/meter so as to keep the total length down to the order ot 10 km. Currently it is only plausible to obtain such fields using the very high energy densities produced by lasers. The luminosity is another issue. I aim for 10 33 to 10 34 but I am conscious that higher luminosities than even these are really desired, especially for an e + e - machine. I tend to assume that the machine is an e + e - machine but it will also accept hadrons

  1. Source and LINAC3 studies

    CERN Document Server

    Bellodi, G

    2017-01-01

    In the framework of the LHC Ion Injector Upgrade pro-gramme (LIU), several activities have been carried out in2016 to improve the ion source and Linac3 performance,with the goal to increase the beam current routinely deliv-ered to LEIR. The extraction region of the GTS-LHC ionsource was upgraded with enlarged vacuum chamber aper-tures and the addition of an einzel lens, yielding highertransmission through the rest of the machine. Also, a seriesof experiments have been performed to study the effects ofdouble frequency mixing on the afterglow performance ofthe source after installation of a Travelling Wave Tube Am-plifier (TWTA) as secondary microwave source at variablefrequency. Measurements have been carried out at a dedi-cated oven test stand for better understanding of the ionsource performance. Finally, several MD sessions werededicated to the study and characterization of the strippingfoils, after evidence of degradation in time was discoveredin the 2015 run.

  2. High duty factor plasma generator for CERN's Superconducting Proton Linac.

    Science.gov (United States)

    Lettry, J; Kronberger, M; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, J-M; Küchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

    2010-02-01

    CERN's Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN's PS-Booster. Its ion source is a noncesiated rf driven H(-) volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H(-) during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the Large Hadron Collider. It consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H(-) during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H(-) plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the required heat dissipation and maintains the original functionality. Materials with higher thermal conductivity are selected and, wherever possible, thermal barriers resulting from low pressure contacts are removed by brazing metals on insulators. The AlN plasma chamber cooling circuit is inspired from the approach chosen for the cesiated high duty factor rf H(-) source operating at SNS.

  3. A linac for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Jason, A.J.

    1998-01-01

    The Spallation Neutron Source Project (SNS), to be constructed at Oak Ridge National Laboratory, accelerates H - ions to an energy of 1.0 GeV with an average current of 1-mA for injection into an accumulator ring that produces the short intense burst of protons needed for the spallation-neutron source. The linac will be the most intense source of H - ions and as such requires advanced design techniques to meet project technical goals. In particular, low beam loss is stressed for the chopped beam placing strong requirements on the beam dynamics and linac construction. Additionally, the linac is to be upgraded to the 2- and 4-MW beam-power levels with no increase in duty factor. The author gives an overview of the linac design parameters and design choices made

  4. Operational experience with the CERN hadron linacs

    International Nuclear Information System (INIS)

    Charmot, H.; Dutriat, C.; Hill, C.E.; Langbein, K.; Lombardi, A.M.; O'Neil, M.; Tanke, E.; Vretenar, M.

    1996-01-01

    The present CERN proton linac (Linac2) was commissioned in 1978 and since that date has been the primary source of protons to the CERN accelerator complex. During the past 18 years, the machine has had a very good reliability record in spite of the demands made upon it. Modifications have been made with the view of maintaining this reliability with reduced resources and new requirements from the users. Further demands will be made in the future for LHC operation. In 1994, a new linac for heavy ion production was put into service replacing the original CERN proton linac. As this machine was built within an international collaboration, operation had to take into account the novelty of the techniques used and the variety of equipment supplied by outside collaborators. Even so, the new machine has also had very good reliability. (author)

  5. System engineering in the SSC Linac

    International Nuclear Information System (INIS)

    Tooker, J.F.; Chang, C.R.; Cutler, R.I.; Funk, L.W.; Guy, F.W.; Hale, R.; Leifeste, G.T.; Nonte, J.; Prichard, B.; Raparia, D.; Saadatmand, K.; Sethi, R.C.; Yao, C.G.

    1992-01-01

    The design and construction of the SSC Linac involves various departments within the SSCL and many outside vendors. The adaptive incorporation of system engineering principles into the SSC Linac is described. This involves the development of specification trees with the breakdown and flow of functional and physical requirements from the top level system specifications to the lower level component specifications. Interfaces are defined, which specify and control the interconnections between the various components. Review cycles are presented during which the requirements, evolution of the design, and test plans are reviewed, monitored, and finalized. The Linac specification tree, interface definition, and reviews of the Linac are presented, including typical examples. (Author) 2 refs., 3 tabs

  6. The invention that is shaping Linac4

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Accelerator experts are no strangers to innovative optimizations of existing techniques and to the development of novel solutions. Sometimes, they even come up with ideas that have the potential to revolutionize the field. This is the case with the Tolerance Aligned Cantilever Mounting (TACM) system, a completely new way of supporting the drift tubes, one of the core elements of linear accelerators. The new, patent-pending technique will be implemented at Linac4.   Drift tubes in a prototype for Linac4, assembled using the new TACM technology. “Assemble and adjust” – that was the technique used to build drift-tube linacs before the arrival of the TACM. Now, the inventors’ motto has become ‘adjust and assemble’. The inversion of these two words represents a real revolution for people working in the field. “The drift tubes are a critical element of Linac4 and they have to satisfy several requirements: they have to be mechanically ...

  7. The mothering of conduct problem and normal children in Spain and the USA: authoritarian and permissive asynchrony.

    Science.gov (United States)

    Wahler, Robert G; Cerezo, M Angeles

    2005-11-01

    Ninety-two clinic-referred and nonclinical mother-child dyads in Spain and the USA were observed in their home settings under naturalistic conditions for a total of 477 hours. Children in the clinic-referred dyads were considered troubled because of conduct problems. The observations were aimed at assessing two forms of mother-child asynchrony, either of which was expected to differentiate clinic referred from nonclinical dyads. Authoritarian asynchrony was defined as a mother's indiscriminate use of aversive reactions to her child, whereas the permissive form entailed indiscriminate positive reactions. Results showed the American mothers to generate more permissive asynchrony, whereas the Spanish mothers were inclined in the authoritarian direction. Only authoritarian asynchrony differentiated the clinical versus nonclinical dyads in each country. Discussion was centered on the greater salience of aversive as opposed to positive maternal attention, and cultural differences between countries that might have accounted for the different parenting styles.

  8. The control system of the CERN new linac

    International Nuclear Information System (INIS)

    Cheretakis, A.; Knott, J.; Mead, P.; Schueren, P. van; Tallgren, U.

    1976-01-01

    Two computers are used for the Linac control system, interfaced to the process over CAMAC, configured in such a way that each computer has direct access to the CAMAC system. The control system is designed in such a way as to minimize the knowledge of programming and computers required by the normal users of the system. The consoles use touch panels for parameter, program and option selections and are interfaced over parallel CAMAC to the computers, whereas the process itself is interfaced over bit serial CAMAC. In the case of the ion source, the CAMAC Serial Highway crosses the 750 kV with the help of optical data links

  9. New linac technology - for SSC, and beyond

    International Nuclear Information System (INIS)

    Jameson, R.A.

    1983-01-01

    With recent agreement on the high priority of seeking funding for a Superconducting Super Collider (SSC), it is appropriate to consider the injector linac requirements for such a machine. In so doing, the status of established technique and advantages of near-term R and D with relatively clear payoff are established, giving a base line for some speculation about linac possibilities even further in the future

  10. University of Washington superconducting booster linac

    International Nuclear Information System (INIS)

    Storm, D.W.; Amsbaugh, J.F.; Cramer, J.G.; Swanson, H.E.; Trainor, T.A.; Vandenbosch, R.; Weitkamp, W.G.; Will, D.I.

    1985-01-01

    We have begun construction of a superconducting linac designed to accelerate ions from protons through about mass 60. Injected by our 9 MV-terminal tandem van de Graaff accelerator, the linac is expected to double the proton energy and quadruple the energies of heavier ions. The resonators are lead plated copper quarter wave structures. The overall layout and expected performance of the accelerator will be presented, along with a brief status report. 3 refs., 3 figs

  11. The trajectory control in the SLC linac

    International Nuclear Information System (INIS)

    Hsu, I.C.; Adolphsen, C.E.; Himel, T.M.; Seeman, J.T.

    1991-05-01

    Due to wake field effects, the trajectories of accelerated beams in the Linac should be well maintained to avoid severe beam breakup. In order to maintain a small emittance at the end of the Linac, the tolerance on the trajectory deviations become tighter when the beam intensities increase. The existing two beam trajectory correction method works well when the theoretical model agrees with the real machine lattice. Unknown energy deviations along the linac as well as wake field effects can cause the real lattice to deviate from the model. This makes the trajectory correction difficult. Several automated procedures have been developed to solve these problems. They are: an automated procedure to frequently steer the whole Linac by dividing the Linac into several small regions; an automated procedure to empirically correct the model to fit the real lattice and eight trajectory correcting feedback loops along the linac and steering through the collimator region with restricted corrector strengths and a restricted number of correctors. 6 refs., 2 figs

  12. The computer program LIAR for the simulation and modeling of high performance linacs

    International Nuclear Information System (INIS)

    Assmann, R.; Adolphsen, C.; Bane, K.; Emma, P.; Raubenheimer, T.O.; Siemann, R.; Thompson, K.; Zimmermann, F.

    1997-07-01

    High performance linear accelerators are the central components of the proposed next generation of linear colliders. They must provide acceleration of up to 750 GeV per beam while maintaining small normalized emittances. Standard simulation programs, mainly developed for storage rings, did not meet the specific requirements for high performance linacs with high bunch charges and strong wakefields. The authors present the program. LIAR (LInear Accelerator Research code) that includes single and multi-bunch wakefield effects, a 6D coupled beam description, specific optimization algorithms and other advanced features. LIAR has been applied to and checked against the existing Stanford Linear Collider (SLC), the linacs of the proposed Next Linear Collider (NLC) and the proposed Linac Coherent Light Source (LCLS) at SLAC. Its modular structure allows easy extension for different purposes. The program is available for UNIX workstations and Windows PC's

  13. Linac4 H− ion sources

    International Nuclear Information System (INIS)

    Lettry, J.; Aguglia, D.; Andersson, P.; Bertolo, S.; Butterworth, A.; Coutron, Y.; Dallocchio, A.; David, N.; Chaudet, E.; Fink, D. A.; Garlasche, M.; Grudiev, A.; Guida, R.; Hansen, J.; Haase, M.; Jones, A.; Koszar, I.; Lallement, J.-B.; Lombardi, A. M.; Machado, C.

    2016-01-01

    CERN’s 160 MeV H − linear accelerator (Linac4) is a key constituent of the injector chain upgrade of the Large Hadron Collider that is being installed and commissioned. A cesiated surface ion source prototype is being tested and has delivered a beam intensity of 45 mA within an emittance of 0.3 π ⋅ mm ⋅ mrad. The optimum ratio of the co-extracted electron- to ion-current is below 1 and the best production efficiency, defined as the ratio of the beam current to the 2 MHz RF-power transmitted to the plasma, reached 1.1 mA/kW. The H − source prototype and the first tests of the new ion source optics, electron-dump, and front end developed to minimize the beam emittance are presented. A temperature regulated magnetron H − source developed by the Brookhaven National Laboratory was built at CERN. The first tests of the magnetron operated at 0.8 Hz repetition rate are described

  14. 25 years of Pelletron Linac facility

    International Nuclear Information System (INIS)

    Shrivastava, A.; Palit, R.

    2014-01-01

    The DAE-BRNS International Symposium on Nuclear Physics was held in BARC during 2nd to 6th December 2013. A summary of the highlights of this symposium has recently appeared in Physics News. As a part of the symposium, a special session was held to commemorate 25 years of operation of the Mumbai Pelletron Linac Facility (PLF). PLF, being operated jointly by Bhabha Atomic Research Centre and Tata Institute of Fundamental Research, has been a major centre for heavy-ion accelerator based research in India. The Pelletron accelerator was formally inaugurated on 30th December 1988, and marked an important milestone in nuclear physics research in India. The facility was augmented with the indigenously developed superconducting LINAC booster to enhance the energy of the accelerated beams. The LINAC booster was commissioned in a phased manner and the entire facility was dedicated to the users on the 28th November 2007. The LINAC booster consists of seven liquid helium cryostat modules, each housing four lead coated (2 μm) copper quarter wave resonators (QWR). The cavities are designed to operate at 150 MHz with an optimum acceptance at a velocity corresponding to β=0.1. The performance of the QWRs is found to be excellent with an average energy gain of 0.4 MV/q per cavity corresponding to 80% of the design value. Beam transmission from the entry to the exit of the LINAC was found to be 80% and the beam timing (FWHM) of 600 ps was measured at the target position. Development of the superconducting LINAC is a major milestone in the accelerator technology in our country. Most of the critical components of the LINAC booster, the first superconducting heavy-ion accelerator in India, have been designed, developed and fabricated indigenously

  15. Comparative study of attachment relationships in young children with symptoms of externalizing disorders: Attention-deficit hyperactivity disorder, oppositional defiant disorder, and conduct disorder and normal children

    Directory of Open Access Journals (Sweden)

    Solmaz Najafi Shoar

    2016-07-01

    Full Text Available This study aimed to compare the relationship of attachment between children with externalizing disorder (ADHD and less conflict and conduct disorder was performed with normal children. And the correlation was causalcomparative research design. The study population included all male students in Year 94 was 12.7 years in Tabriz To this aim, and to a multi-stage random sampling method, a sample of 200 (150 patients with symptoms and 50 normal KCAQ people were selected and CSI-4 was performed on them. The data were analyzed using ANOVA. The results showed that children with externalizing disorders and normal children in terms of attachment there is a significant difference (P <0/005. So that children with attention disorders and children with the disorder more or less active and less conflict in relationships have insecure attachment styles. Another finding of the study showed that children with conduct disorder, avoidant, ambivalent insecure attachment relationships are the common children are secure attachment relationships. Thus, the results of this study have practical implications in clinical areas to the extent that the design of such attachment-based interventions are necessary.

  16. Thermal Conductance and High-Frequency Properties of Cryogenic Normal or Superconducting Semi-rigid Coaxial Cables in the Temperature Range of 1-8 K

    Science.gov (United States)

    Kushino, A.; Kasai, S.; Ukibe, M.; Ohkubo, M.

    2018-04-01

    In this study, the characteristics of thin semi-rigid cables composed of different conductors and with outer diameters ranging from 0.86 to 1.19 mm were investigated at low temperatures. The thermal conductance was measured between approximately 1 and 8 K, and the frequency dependence of the attenuation in the cables was obtained at 3 K. The electrical conductors used in the cables were alloys: beryllium copper, brass, stainless steel (SUS304), phosphor bronze, cupronickel (CuNi), and niobium-titanium (NbTi). The thermal conductance of a commercial miniature coaxial cable with braided wires forming the outer electrical conductor was also examined for reference. The measured thermal conductance was compared to published data and that generated from material libraries and databases. Among the measured cables using normal metals, the semi-rigid cable composed of SUS304 conductors and a polytetrafluoroethylene insulator showed the lowest thermal conductance. The transmission performance of the semi-rigid cables using SUS304 or CuNi was improved by plating the central conductors with a silver coating of approximately 3 μm thickness, and their thermal conductance with the plating increased by approximately one order of magnitude. The superconducting NbTi semi-rigid cable exhibited the lowest thermal conductance of all the cables considered in the present study along with very small attenuation up to above 5 GHz.

  17. Dispersion and betatron matching into the linac

    International Nuclear Information System (INIS)

    Decker, F.J.; Adolphsen, C.; Corbett, W.J.; Emma, P.; Hsu, I.; Moshammer, H.; Seeman, J.T.; Spence, W.L.

    1991-05-01

    In high energy linear colliders, the low emittance beam from a damping ring has to be preserved all the way to the linac, in the linac and to the interaction point. In particular, the Ring-To-Linac (RTL) section of the SLAC Linear Collider (SLC) should provide an exact betatron and dispersion match from the damping ring to the linac. A beam with a non-zero dispersion shows up immediately as an increased emittance, while with a betatron mismatch the beam filaments in the linac. Experimental tests and tuning procedures have shown that the linearized beta matching algorithms are insufficient if the actual transport line has some unknown errors not included in the model. Also, adjusting quadrupole strengths steers the beam if it is offset in the quadrupole magnets. These and other effects have lead to a lengthy tuning process, which in the end improves the matching, but is not optimal. Different ideas will be discussed which should improve this matching procedure and make it a more reliable, faster and simpler process. 5 refs., 2 figs

  18. Argonne superconducting heavy-ion linac

    International Nuclear Information System (INIS)

    Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

    1976-01-01

    A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2 0 K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (ΔE/E approximately equal to 2 x 10 -4 ) or very good time resolution

  19. Challenges of the ILC Main Linac

    International Nuclear Information System (INIS)

    Ross, Marc

    2007-01-01

    With the completion of the ILC Reference Design Report (RDR), we begin the next phase of the project - development of the Engineering Design. Our strategy and priorities come from the identification, contained in the RDR, of scientific and engineering challenges of the ILC. First among these is the cost of the main linac which, including the associated earthworks and cooling/power systems, amounts to 60% of the ILC total cost. Next is the challenge to reach the highest practical gradient since this R and D has the largest cost leverage of any of the ongoing programs. Finally, we have to understand the beam dynamics and beam tuning processes in the main linac, as we will not have the opportunity to do full (or even large) scale tests of these before the linac is constructed.

  20. Integrated design of the SSC linac injector

    International Nuclear Information System (INIS)

    Evans, D.; Valiecnti, R.; Wood, F.

    1992-01-01

    The Ion Source, Low Energy Beam Transport (LEBT), and Radio Frequency Quadrupole (RFQ) of the Superconducting Super Collider (SSC) Linac act as a unit (referred to as the Linac Injector), the Ion Source and LEBT being cantilevered off of the RFQ. Immediately adjacent to both ends of the RFQ cavity proper are endwall chambers containing beam instrumentation and independently-operated vacuum isolation valves. The Linac Injector delivers 30 mA of H - beam at 2.5 MeV. This paper describes the design constraints imposed on the endwalls, aspects of the integration of the Ion Source and LEBT including attachment to the RFQ, maintainability and interchangeability of LEBTs, vacuum systems for each component, and the design of necessary support structure. (Author) 2 tab

  1. Heavy ion induction linacs for fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.; Ho, D.D.M.

    1991-01-01

    In 1976 Denis Keefe proposed the heavy ion induction linac as a driver for inertial confinement fusion (ICF) power plants. Subsequent research has established that heavy ion fusion (HIF) is potentially an attractive energy source and has identified the issues that must be resolved to make HIF a reality. The principal accelerator issues are achieving adequately low transverse and longitudinal emittance and acceptable cost. Results from the single and multiple beam experiments at LBL on transverse emittance are encouraging. A predicted high current longitudinal instability that can affect longitudinal emittance is currently being studied. This paper presents an overview of economics and ICF target requirements and their relationship to accelerator design. It also presents a summary of the status of heavy ion induction linac research. It concludes with a discussion of research plans, including plans for the proposed Induction Linac Systems Experiments (ILSE)

  2. Focussing magnets for proton Linac of ADS

    International Nuclear Information System (INIS)

    Malhotra, Sanjay; Mahapatra, U.; Singh, Pitamber; Choudhury, R.K.; Goel, Priyanshu; Verma, Vishnu; Bhattacharya, S.; Srivastava, G.P.; Kailas, S.; Sahni, V.C.

    2009-01-01

    A linear accelerator comprising of Radio frequency quadruple (RFQ) and drift tube linac (DTL) is being developed by BARC. The Alvarez type post-coupled cw DTL accelerates protons from an energy of 3 MeV to 20 MeV. The drift tube linac is excited in TM010 mode, wherein the particles are accelerated by longitudinal electric fields at the gap crossings between drift tubes. The particles are subjected to transverse RF defocusing forces at the gap crossings due to the increasing electric fields in the gap. The transverse defocusing is corrected by housing magnetic quadrupole focussing lenses inside the drift tubes. The permanent magnet quadrupoles (PMQs) are placed inside the hermetically sealed drift tubes and provide a constant magnetic field gradient in the beam aperture. This paper discusses various aspects of magnetic design, selection of magnetic materials and the engineering development involved in the prototype development of these drift tubes for proton Linac. (author)

  3. ARIEL e-LINAC: Commissioning and Development

    Science.gov (United States)

    Laxdal, R. E.; Zvyagintsev, V.

    2016-09-01

    A superconducting electron Linac (e-Linac) will be a part of the ARIEL facility for the production of radioactive ion beams (RIB) at TRIUMF. The e-Linac will consist of five 1.3GHz 9-cell cavities in three cryomodules delivering a 50MeV 10mA beam. The baseline operation will be single pass but a re-circulating ring is planned to allow either energy boost or energy recovery operation. The first stage of the accelerator which consists of two cryomodules has been successfully commissioned in 2014. The paper will discuss the superconducting radio-frequency (SRF) challenges of the accelerator. Cavities, crymodules and RF system design, preparation, and performance will be presented.

  4. Electro neutrons around a 12 MV Linac

    International Nuclear Information System (INIS)

    Vega C, H. R.; Perez L, L. H.

    2012-10-01

    Neutron contamination around Linacs for radiotherapy is a source of undesirable doses for the patient. The main source of these neutrons is the photonuclear reactions occurring in the Linac head and the patient body. Electrons also produce neutrons through (e, en) reactions. This reaction is known as electro disintegration and is carried out by the electron scattering that produce a virtual photon that is absorbed by the scattering nucleus producing the reaction e + A → (A-1) + n + e'. In this work the electron-neutron spectrum to 100 cm from the isocenter of a 12 MV Linac has been measured using a passive Bonner spheres spectrometer in a novel procedure named Planetary mode. (Author)

  5. ARIEL e-LINAC: Commissioning and Development

    International Nuclear Information System (INIS)

    Laxdal, R.E.; Zvyagintsev, V.

    2016-01-01

    A superconducting electron Linac (e-Linac) will be a part of the ARIEL facility for the production of radioactive ion beams (RIB) at TRIUMF. The e-Linac will consist of five 1.3GHz 9-cell cavities in three cryomodules delivering a 50MeV 10mA beam. The baseline operation will be single pass but a re-circulating ring is planned to allow either energy boost or energy recovery operation. The first stage of the accelerator which consists of two cryomodules has been successfully commissioned in 2014. The paper will discuss the superconducting radio-frequency (SRF) challenges of the accelerator. Cavities, crymodules and RF system design, preparation, and performance will be presented. (paper)

  6. Magnetron based high energy S-band linac system

    International Nuclear Information System (INIS)

    Tiwari, T.; Krishnan, R.; Phatangare, Manoj

    2012-01-01

    This paper deals with the study of magnetron based high energy S-band linear accelerator (linac) system operating at spot frequency 2.998 GHz. The energy and dose are two important parameters of linac system which depend on input power of microwave source and length of linac tube. Here the author has studied how these parameters can be improved for side coupled standing wave S-band linac system

  7. Proton induction linacs as high-intensity neutron sources

    International Nuclear Information System (INIS)

    Keefe, D.; Hoyer, E.

    1981-01-01

    Proton induction linacs are explored as high intensity neutron sources. The induction linac - concept, properties, experience with electrons, and possibilities - and its limitations for accelerating ions are reviewed. A number of proton induction linac designs are examined with the LIACEP program and general conclusions are given. Results suggest that a proton induction accelerator of the lowest voltage, consistent with good neutron flux, is preferred and could well be cost competitive with the usual rf linac/storage ring designs. (orig.)

  8. Application of RF Superconductivity to High-Current Linac

    International Nuclear Information System (INIS)

    Chan, K.C.D.

    1998-01-01

    In 1997, the authors initiated a development program in Los Alamos for high-current superconducting proton-linac technology to build prototypes components of this linac to demonstrate the feasibility. The authors are building 700-MHz niobium cavities with elliptical shapes, as well as power couplers to transfer high RF power to these cavities. The cavities and power couplers will be integrated in cryostats as linac cryomodules. In this paper, they describe the linac design and the status of the development program

  9. Development of the Medium Energy Linac Systems

    International Nuclear Information System (INIS)

    Jang, Ji Ho; Kwon, Hyeok Jung; Kim, Dae Il; Kim, Han Sung; Park, Bum Sik; Seol, Kyung Tae; Song, Young Gi; Yun, Sang Pil; Cho, Yong Sub; Hong, In Seok

    2008-05-01

    The main purpose of this project is developing 100-MeV proton linear accelerator (linac) for proton engineering frontier project (PEFP). In the first phase of the PEFP, the development of the 20-MeV linac has successfully finished. Hence the work scope of this project is designing the linac to accelerate proton beams from 20-MeV up to 100-MeV, fabricating the linac up to 45 MeV, fabricating one set of the medium energy beam transport (MEBT) tank, and developing the low level radio frequency (LLRF) system and the control system. The basic role of the new proton accelerator is accelerating 20-mA proton beams from 20 MeV up to 100 MeV. The first step of the design procedure is optimizing and determining the accelerator parameters. The beam loss is also main concern in the design stage. The drift tube (DT) and the quadrupole magnets are designed to be optimized to the new linac design. The other purpose is confirming the new design by fabricating and tuning the drift tube linac (DTL). The 20MeV proton beam divided into two directions. One is supplying the beams to user group by turning on the 45-degree bending magnet. The other is guided into the 100-MeV DTL by tuning off the dipole magnet. That is why the PEFP MEBT located after 20-MeV DTL. The MEBT is realized as two small DTL tanks with three cells and a 45-degree bending magnet. The fabrication of one MEBT tank is another purpose of this project. The other purposes of this project is developing the LLRF system to control the RF signal and control system to monitor and control the vacuum system, magnet power supply, etc

  10. Linac design algorithm with symmetric segments

    International Nuclear Information System (INIS)

    Takeda, Harunori; Young, L.M.; Nath, S.; Billen, J.H.; Stovall, J.E.

    1996-01-01

    The cell lengths in linacs of traditional design are typically graded as a function of particle velocity. By making groups of cells and individual cells symmetric in both the CCDTL AND CCL, the cavity design as well as mechanical design and fabrication is simplified without compromising the performance. We have implemented a design algorithm in the PARMILA code in which cells and multi-cavity segments are made symmetric, significantly reducing the number of unique components. Using the symmetric algorithm, a sample linac design was generated and its performance compared with a similar one of conventional design

  11. BARC-TIFR Pelletron Linac facility

    International Nuclear Information System (INIS)

    Gore, J.A.; Gupta, A.K.; Saxena, A.

    2017-01-01

    The Pelletron Accelerator, set up as a collaborative project between the Bhabha Atomic Research Centre and the Tata Institute of Fundamental Research, has been serving as the workhorse for the heavy ion accelerator based research in India since its commissioning in December 30, 1988. The facility was augmented with an indigenously developed superconducting Linac booster to enhance the energy of the Pelletron accelerated beams and was fully commissioned on November 28, 2007. The augmented facility is renamed as Pelletron Linac facility (PLF). While the PLF is predominantly utilized by the experimental users from BARC and TIFR, the users include researchers from other research institutions and universities within India and abroad

  12. EG and G electron linac modifications

    International Nuclear Information System (INIS)

    Norris, N.J.; Detch, J.L.; Kocimski, S.M.; Sawyer, C.R.; Hudson, C.L.

    1986-01-01

    A three-year modification of the EG and G electron linac has been performed to replace obsolete equipment and bring all subsystems up to the current state of the art. Components and subsystems were designed, constructed, and tested off-line to minimize interruption of experiments. The configuration of the modified linac is shown schematically, and performance characteristics are give. Each subsystem is described, including: the electron gun; solenoid focusing system; subharmonic bunchers; accelerating system; RF system; klystron modulators and power supplies; control system; beam handling system; vacuum system; and beam current monitors. 7 refs., 4 figs., 2 tabs

  13. Proton linacs for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Lennox, A.J.

    1993-08-01

    Recent advances in the ability to deliver boron-containing drugs to brain tumors have generated interest in ∼4 MeV linacs as sources of epithermal neutrons for radiation therapy. In addition, fast neutron therapy facilities have been studying methods to moderate their beams to take advantage of the high cross section for epithermal neutrons on boron-10. This paper describes the technical issues involved in each approach and presents the motivation for undertaking such studies using the Fermilab linac. the problems which must be solved before therapy can begin are outlined. Status of preparatory work and results of preliminary measurements are presented

  14. 4-rod RFQ linac for ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Fujisawa, Hiroshi; Hamamoto, Nariaki; Inouchi, Yutaka [Nisshin Electric Co. Ltd., Kyoto (Japan)

    1997-03-01

    A 34 MHz 4-rod RFQ linac system has been upgraded in both its rf power efficiency and beam intensity. The linac is able to accelerate in cw operation 0.83 mA of a B{sup +} ion beam from 0.03 to 0.91 MeV with transmission of 61 %. The rf power fed to the RFQ is 29 kW. The unloaded Q-value of the RFQ has been improved approximately 61 % to 5400 by copper-plating stainless steel cooling pipes in the RFQ cavity. (author)

  15. Preinjector for Linac 1, accelerating column

    CERN Multimedia

    1974-01-01

    For a description of the Linac 1 preinjector, please see first 7403070X. High up on the wall of the Faraday cage (7403073X) is this drum-shaped container of the ion source (7403083X). It is mounted at the HV end of the accelerating column through which the ions (usually protons; many other types of ions in the course of its long history) proceed through the Faraday cage wall to the low-energy end (at ground potential) of Linac 1. The 520 kV accelerating voltage was supplied by a SAMES generator (7403074X).

  16. Modeling radiation loads in the ILC main linac and a novel approach to treat dark current

    Energy Technology Data Exchange (ETDEWEB)

    Mokhov, Nilolai V. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Rakhno, Igor L. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Tropin, Igor S. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2017-09-11

    Electromagnetic and hadron showers generated by electrons of dark current (DC) can represent a significant radiation threat to the ILC linac equipment and personnel. In this study, a commissioning scenario is analysed which is considered as the worst-case scenario for the main linac regarding the DC contribution to the radiation environment in the tunnel. A normal operation scenario is analysed as well. An emphasis is made on radiation load to sensitive electronic equipment—cryogenic thermometers inside the cryomodules. Prompt and residual dose rates in the ILC main linac tunnels were also calculated in these new high-statistics runs. A novel approach was developed—as a part of general purpose Monte Carlo code MARS15—to model generation, acceleration and transport of DC electrons in electromagnetic fields inside SRF cavities. Comparisons were made with a standard approach when a set of pre-calculated DC electron trajectories is used, with a proper normalization, as a source for Monte Carlo modelling. Results of MARS15 Monte Carlo calculations, performed for the current main linac tunnel design, reveal that the peak absorbed dose in the cryogenic thermometers in the main tunnel for 20 years of operation is about 0.8 MGy. The calculated contact residual dose on cryomodules and tunnel walls in the main tunnel for typical irradiation and cooling conditions is 0.1 and 0.01 mSv/hr, respectively.

  17. Progress Report on SIMULINK Modelling of RF Cavity Control for SPL Extension to LINAC4 Theory and Analysis behind Simulation Results of SPL Model Using I/Q Components in SIMULINK to Date, Including Lorentz Force Effects and Multiple Cavities Driven by Single Feedback Loop

    CERN Document Server

    Hernandez, M

    2011-01-01

    In the context of a luminosity upgrade for the LHC within the coming years, works have started on LINAC4 to provide an infrastructure for updating the LHC supplier chain. In order to achieve energy levels and particles per bunch necessary for the expected rate of events at LHC detectors and related experiments, a project proposal is underway for an appended Superconducting Proton LINAC (SPL) that will run from the normal conducting LINAC4 and LP-SPL onto the LHC supplier chain. Thus, the SPL will have two main functions: Firstly, to provide H- beam for injection into the PS2 which is compatible with LHC luminosity. For this purpose the SPL will accelerate the output beam of LINAC4 from 1GeV to 4GeV,removing, at the same time, the necessity for PSB operation in the LHC supply chain. Secondly, it will provide an infrastructure upgradeable to meet the needs of all potential high-power proton users at CERN (EURISOL) and possibly neutrino production facilities. For high-power applications of this nature the SPL wi...

  18. Alternate Tunings for the Linac Coherent Light Source Photoinjector

    CERN Document Server

    Limborg-Deprey, Cecile

    2005-01-01

    The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser (FEL) project based on the SLAC linac. The LCLS Photoinjector beamline has been designed to deliver 10 ps long electron bunches of 1nC with a normalized transverse emittance of less than 1 mm.mrad for 80% of the slices constituting the core of the bunch at 135 MeV. Tolerances and regulation requirements are tight for this tuning. The main contribution to emittance is the "cathode emittance which counts for 0.72 mm.mrad for the nominal tuning. As the "cathode emittance" scales linearly with laser spot radius, the emittance will be dramatically reduced for smaller radius, but this is only possible at lower charge. In particular, for a 0.2nC, we believe we can achieve an emittance closer to 0.4 mm.mrad. This working point will be easier to tune and the beam quality should be much easier to maintain than for the nominal one. In this paper, we also discuss how emittance could be further reduced by using the appropriate laser pulse shaping.

  19. 10 MeV RF electron linac for industrial applications

    International Nuclear Information System (INIS)

    2017-01-01

    Electron linacs have found numerous applications in the field of radiation processing on an industrial scale. High power RF electron linacs are commonly used for food irradiation, medical sterilization, cross-linking of polymers, etc. For this purpose, the 10 MeV RF linac has been indigenously designed, developed, commissioned and is being used regularly at 3 kW beam power. This paper gives a brief description of the linac and its utilization for various applications. Safety considerations and regulatory aspects of the linac are also discussed

  20. Neutron and photon spectra in LINACs

    International Nuclear Information System (INIS)

    Vega-Carrillo, H.R.; Martínez-Ovalle, S.A.; Lallena, A.M.; Mercado, G.A.; Benites-Rengifo, J.L.

    2012-01-01

    A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10 –6 and 1 MeV. Neutron and the Bremsstrahlung spectra show the same features regardless of the linac voltage. - Highlights: ► With MCNPX code realistic models of two LINACs were built. ► Photon and neutron spectra below the flattening filter and at the isocenter were calculated. ► Neutron spectrum at the flattening filter was compared against the Tosi et al. source-term model. ► Tosi et al. model underestimates the neutron contribution below 1 MeV. ► Photon spectra look alike to those published in literature.

  1. Microphonic measurements on superconducting linac structures

    International Nuclear Information System (INIS)

    Marzali, A.; Schwettman, H.A.

    1992-01-01

    Microphonics in multi-cell linac structures lead to energy and pointing modulation of the electron beam despite RF stabilization. Evaluation of the microphonic behaviour of a 500 MHz two cell structure is planned in collaboration with Lawrence Berkeley Laboratory and Brookhaven National Laboratory. In this paper we describe a method of evaluation based on accelerometer measurements. (Author) fig., 2 tabs., 5 refs

  2. Preinjector for Linac 1, ion source

    CERN Multimedia

    1974-01-01

    For a description of the Linac 1 preinjector, please see first 7403070X. Inside the drum-shaped container shown in 7403081X, is the ion source with its associated electronics. It sits at the HV end of the accelerating column seen also in 7403081.

  3. Status of the Novosibirsk energy recovery linac

    International Nuclear Information System (INIS)

    Bolotin, V.P.; Vinokurov, N.A.; Gavrilov, N.G.; Kayran, D.A.; Knyazev, B.A.; Kolobanov, E.I.; Kotenkov, V.V.; Kubarev, V.V.; Kulipanov, G.N.; Matveenko, A.N.; Medvedev, L.E.; Miginsky, S.V.; Mironenko, L.A.; Oreshkov, A.D.; Ovchar, V.K.; Popik, V.M.; Salikova, T.V.; Serednyakov, S.S.; Skrinsky, A.N.; Shevchenko, O.A.; Scheglov, M.A.; Tcheskidov, V.G.

    2006-01-01

    The Novosibirsk terahertz free electron laser is based on the energy recovery linac (ERL) with room-temperature radiofrequency system. Some features of the ERL are discussed. The results of emittance measurements and electron optics tests are presented. The second stage of the ERL, which has four orbits, is described briefly

  4. Linac based radiosurgery and stereotactic radiotherapy

    International Nuclear Information System (INIS)

    Mackie, T.R.

    2008-01-01

    The following topics were discussed: Definition of stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT); Stereo market; Indications for SRS/SRT; History of linac-based SRS/SRT; Variety of systems; QA for SRS; Localization; and Imaging. (P.A.)

  5. First beam in Linac4 DTL

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Following the installation of the Linac4 Drift Tube Linac (DTL) earlier this summer (see here), the first DTL tank saw beams at 12 MeV on 5 August.   Transverse emittance measured at 12 MeV after the DTL tank1 using a temporary slit-and-grid emittance device. You never forget your first beam. That was especially true for the Linac4 DTL team, as it followed years of design, construction and vigorous testing. "We performed countless measurements of the geometry, vacuum and magnet polarisation of the DTL tanks while we were in the workshop," says Suitbert Ramberger, project engineer for the Linac4 DTL. "Add that preparation to the excellent RF conditioning that we carried out in the weeks before the beam tests and I was confident that the acceleration with beam would fully meet expectations!" Indeed it did. Beam commissioning tests ran until 21 August and found the DTL operating with nominal transmission. This successful run has confirmed the innovative design ...

  6. Linac technology for free-electron lasers

    International Nuclear Information System (INIS)

    Cooper, R.K.; Morton, P.L.; Wilson, P.B.; Keefe, D.; Faltens, A.

    1983-01-01

    The purpose of this paper is to concentrate on the properties of high-energy electron linear accelerators for use in free-electron lasers operating principally in the Compton regime. To fix our focus somewhat, we shall consider electron energies in the 20- to 200-MeV range and consider requirements for high-power free-electron lasers operating in the 0.5- to 10-μm range. Preliminary remarks are made on high-power free-electron laser amplifiers and oscillators and some desirable characteristics of the linacs that deliver electron beams for these devices. Both the high peak-current requirements of the amplifier and the high pulse-repetition frequency requirements of the oscillator can be met by present-day linac technology, although not necessarily by the same machine. In this papers second and third section, the technology of two rather different types of linear accelerators, the rf linac and the induction linac, is reviewed. In conclusion, applications to the Free Electron Lasers are stated

  7. CEBAF Cryomodule Commissioning in the South Linac

    International Nuclear Information System (INIS)

    M. Drury; H. Lankford; T. Lee; J. Marshall; J. Preble; Q. Saulter; W. Schneider; Michael Spata; Mark Wiseman

    1993-01-01

    When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, 38 1/4 cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz[1]. A cryomodule must provide an energy gain of 20 MeV to the 200 mu-A beam[2]. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's (Q(sub ext)) of the cavity ports, the unloaded Q (Q(sub 0)) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity[3]. Finally, the mechanical tuners are cycled and characterized. A portable test stand allows local control of the rf system and provides automated data acquisition. During the period from April 1993 through September 1993, 16 of the 20 cryomodules installed in the South Linac were commissioned. All cryomodules tested in the South Linac meet or exceed the CEBAF specifications. This paper describes the results of the commissioning of the first 10 cryomodules in the South Linac

  8. Preinjector for Linac 1, SAMES generator

    CERN Multimedia

    1974-01-01

    For a description of the Linac 1 preinjector, please see first 7403070x. When the original 520 kV Cockcroft-Walton generator broke down in 1973, it was replaced by this much smaller 520 kV SAMES generator, seen here sitting on the floor of the Faraday cage.

  9. Upgrade of GUI for linac control

    International Nuclear Information System (INIS)

    Oonuma, Tadahiro; Shibasaki, Yoshinobu

    1993-01-01

    We are now upgrading GUI(Graphical User Interface) of the control system at Tohoku Linac. This system uses Personal Computer (DECpc466D2LP-66MHz) and Visual Basic which makes coding GUI easy and simple. The first results of this system are presented. (author)

  10. Mechanical design and fabrication of the VHF-gun, the Berkeley normal-conducting continuous-wave high-brightness electron source

    Science.gov (United States)

    Wells, R. P.; Ghiorso, W.; Staples, J.; Huang, T. M.; Sannibale, F.; Kramasz, T. D.

    2016-02-01

    A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. The basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.

  11. Heat Capacity and Thermal Conductance Measurements of a Superconducting-Normal Mixed State by Detection of Single 3 eV Photons in a Magnetic Penetration Thermometer

    Science.gov (United States)

    Stevenson, T. R.; Balvin, M. A.; Bandler, S. R.; Denis, K. L.; Lee, S.-J.; Nagler, P. C.; Smith, S. J.

    2015-01-01

    We report on measurements of the detected signal pulses in a molybdenum-gold Magnetic Penetration Thermometer (MPT) in response to absorption of one or more 3 eV photons. We designed and used this MPT sensor for x-ray microcalorimetry. In this device, the diamagnetic response of a superconducting MoAu bilayer is used to sense temperature changes in response to absorbed photons, and responsivity is enhanced by a Meissner transition in which the magnetic flux penetrating the sensor changes rapidly to minimize free energy in a mixed superconducting normal state. We have previously reported on use of our MPT to study a thermal phonon energy loss to the substrate when absorbing x-rays. We now describe results of extracting heat capacity C and thermal conductance G values from pulse height and decay time of MPT pulses generated by 3 eV photons. The variation in C and G at temperatures near the Meissner transition temperature (set by an internal magnetic bias field) allow us to probe the behavior in superconducting normal mixed state of the condensation energy and the electron cooling power resulting from quasi-particle recombination and phonon emission. The information gained on electron cooling power is also relevant to the operation of other superconducting detectors, such as Microwave Kinetic Inductance Detectors.

  12. Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

    1976-01-01

    A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2/sup 0/K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (..delta..E/E approximately equal to 2 x 10/sup -4/) or very good time resolution (..delta.. t approximately equal to 30 psec).

  13. Superconducting LINAC booster for the Mumbai pelletron

    Indian Academy of Sciences (India)

    relative to normal ones, a substantial reduction in electric power to maintain large electric fields can be ... Design and construction of a suitable cryogenic system. • Fabrication of ... The QWR is essentially an open-ended λ/4 coaxial transmission line capable of sup- ... helium, while the outer can is cooled by conduction.

  14. Photocathode electron linac for AFEL

    International Nuclear Information System (INIS)

    Wood, R.L.; Young, L.M.; Aikin, D.J.; Clark, W.L.; DePaula, R.F.; Gladwell, C.; Ledford, J.E.; Martinez, F.A.; Stovall, J.E.

    1992-01-01

    A compact, high brightness accelerator was designed and fabricated by Los Alamos National Laboratory for use in the Advanced Free Electron Laser facility. A brazed copper, 1300 MHz, 20 MeV structure is suspended within a thermally insulating vacuum vessel. Integral cooling passages allow introduction of cooling water for normal operation, or liquid nitrogen for cryogenic operation. Its exceptional beam quality is expected to enhance the performance of the FEL experiments planned for the AFEL facility

  15. LINAC5 - A Quasi-Alvarez Linac for BioLEIR

    International Nuclear Information System (INIS)

    Garland, J M; Lallement, J-B; Lombardi, A

    2017-01-01

    LINAC5 is a new linac proposed for the acceleration of light ions with Q/A = 1/3 to 1/4 for medical applications within the BioLEIR (Low Energy Ion Ring) design study at CERN. We propose a novel quasi-Alvarez drift-tube linac (DTL) accelerating structure design for LINAC5, which can reduce the length of a more conventional DTL structure, yet allows better beam focussing control and flexibility than the inter-digital H (IH) structures typically used for modern ion acceleration. We present the main sections of the linac with total length ∼12 m, including a 202 MHz radio frequency quadrupole (RFQ) a matching medium energy beam transport (MEBT) and a 405 MHz quasi-Alvarez accelerating section with an output energy of 4.2 MeV/u. Permanent magnet quadrupoles are proposed for use in the quasi-Alvarez structure to improve the compactness of the design and increase the efficiency. Lattice design considerations, multi-particle beam dynamics simulations and RFQ and radio frequency (RF) cavity designs are presented. (paper)

  16. Current status of femtosecond triplet Linacs 2000

    International Nuclear Information System (INIS)

    Uesaka, M.; Watanabe, T.; Kobayashi, T.

    2000-01-01

    Femtosecond Ultrafast Quantum Phenomenon Research Facility has been commissioned in 2000. It consists the femtosecond linac-laser synchronization system, the 12 TW 50 fs laser system and the analyzing system. Laser photocathode RF gun produced l kA = 7 nC / 7 ps for 250 μJ 267 nm laser irradiation, synchronization of 300 fs (rms) for minutes and l.9 ps (rms) for hours was established. Efforts to avoid such long-term drift are under way. This system is applied to subpico- and picosecond pulseradiolysis for radiation chemistry of water and supercritical water. Laser plasma linac works are under way to generate 20 MeV 10 fs electron bunch and ps ion beam using the 12 TW 50 fs laser. Further, the time-resolved X-ray diffraction is close to dynamic visualization of atomic motions. (author)

  17. Superconducting linac booster for NSC Pelletron

    International Nuclear Information System (INIS)

    Roy, A.; Prakash, P.N.; Ajithkumar, B.P.; Ghosh, S.; Changrani, T.; Mehta, R.; Sarkar, A.; Muralidhar, S.; Dutt, R.N.; Kumar, M.; Shepard, K.W.; and others.

    1996-01-01

    The progress made in the heavy ion superconducting linac booster project for the Nuclear Science Centre Pelletron accelerator is overviewed. Prototypes of the accelerating structure have been fabricated at Argonne National Laboratory and undergone several diagnostic tests. In the first phase heavy ions up to mass 80 will be accelerated to energies above the Coulomb barrier and in the second phase the mass limit would be increased to 120. The subsystems of the project are the basic accelerating structures, the RF instrumentation and control, the cryogenic system and the beam optics. Preliminary designs for the buncher and linac cryostats have been made. Several prototypes of RF electronics and control modules have been fabricated and tested. (R.P.)

  18. Operation of the tandem-linac accelerator

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The tandem-linac accelerator system is operated as a source of energetic heavy-ion projectiles for research in several areas of nuclear physics and occasionally in other areas of science. The accelerator system consists of a 9-MV tandem electrostatic accelerator and a superconducting-linac energy booster that can provide an additional 20 MV of acceleration. A figure shows the layout of this system, which will be operated in its present form until September 1985, when it will be incorporated into the larger ATLAS system. In both the present and future forms the accelerator is designed to provide the exceptional beam quality and overall versatility required for precision nuclear-structure research

  19. The source development lab linac at BNL

    International Nuclear Information System (INIS)

    Graves, W.S.; Johnson, E.D.

    1996-12-01

    A 210 MeV SLAC-type electron linac is currently under construction at BNL as part of the Source Development Laboratory. A 1.6 cell RF photoinjector is employed as the high brightness electron source which is excited by a frequency tripled Titanium:Sapphire laser. This linac will be used for several source development projects including a short bunch storage ring, and a series of FEL experiments based on the 10 m long NISUS undulator. The FEL will be operated as either a SASE or seeded beam device using the Ti:Sapp laser. For the seeded beam experiments; direct amplification, harmonic generation, and chirped pulse amplification modes will be studied, spanning an output wavelength range from 900 nm down to 100 nm. This paper presents the project's design parameters and results of recent modeling using the PARMELA and MAD simulation codes

  20. Electron linac design for pion radiotherapy

    International Nuclear Information System (INIS)

    Loew, G.A.; Brown, K.L.; Miller, R.H.; Walz, D.R.

    1977-03-01

    The electron linac provides a straightforward, state-of-the-art method of producing the primary beam required for a hospital-based multiport pion radiotherapy facility for cancer treatment. The accelerator and associated beam transport system described are capable of generating an electron beam of about 250 kW and delivering it alternately to one of several pion generators and treatment areas. Each pion generator, a prototype of which now exists at the Stanford W. W. Hansen Laboratory, would contain a target for the electron beam and sixty separate superconducting magnet channels which focus the pions in the patient. The considerations which enter the design of a practical linac are presented together with a possible layout of a flexible beam transport system

  1. New high power linacs and beam physics

    International Nuclear Information System (INIS)

    Wangler, T.P.; Gray, E.R.; Nath, S.; Crandall, K.R.; Hasegawa, K.

    1997-01-01

    New high-power proton linacs must be designed to control beam loss, which can lead to radioactivation of the accelerator. The threat of beam loss is increased significantly by the formation of beam halo. Numerical simulation studies have identified the space-charge interactions, especially those that occur in rms mismatched beams, as a major concern for halo growth. The maximum-amplitude predictions of the simulation codes must be subjected to independent tests to confirm the validity of the results. Consequently, the authors compare predictions from the particle-core halo models with computer simulations to test their understanding of the halo mechanisms that are incorporated in the computer codes. They present and discuss scaling laws that provide guidance for high-power linac design

  2. Superconducting RF for energy-recovery linacs

    International Nuclear Information System (INIS)

    Liepe, M.; Knobloch, J.

    2006-01-01

    Since superconducting RF for particle accelerators made its first appearance in the 1970s, it has found highly successful application in a variety of machines. Recent progress in this technology has made so-called Energy-Recovery Linacs (ERLs)-originally proposed in 1965-feasible, and interest in this type of machine has increased enormously. A superconducting linac is the driving heart of ERLs, and emittance preservation and cost efficiency is of utmost importance. The resulting challenges for the superconducting cavity technology and RF field control are manifold. In March 2005 the first international workshop on ERLs was held at Newport News, VA, to explore the potential of ERLs and to discuss machine-physics and technology challenges and their solutions. This paper reviews the state-of-the-art in superconducting RF and RF control for ERLs, and summarizes the discussions of the SRF working group on this technology during the ERL2005 workshop

  3. Low-energy linac structure for PIGMI

    International Nuclear Information System (INIS)

    Swenson, D.A.; Stovall, J.E.

    1977-01-01

    The higher radio frequency (450 MHz) and lower injection energy (250 keV) of the PIGMI (Pion Generator for Medical Irradiations) linac design seriously compound the problem of beam containment in the first few meters of the structure. The conventional quadrupole-focused, drift-tube linac represents the best solution for beam energies above 8 MeV, but because of the small space available for quadrupoles in the PIGMI designs, cannot provide the required focusing at lower energies. A satisfactory solution to this focusing problem has been found based on pure alternating phase focusing for the first few MeV, followed by a smooth transition to a pure permanent magnet quadrupole-focused structure at 8 MeV. The structure and its calculated performance are described

  4. Induction linacs for heavy ion fusion research

    International Nuclear Information System (INIS)

    Fessenden, T.J.; Avery, R.T.; Brady, V.; Bisognano, J.; Celata, C.; Chupp, W.W.; Faltens, A.; Hartwig, E.C.; Judd, D.L.; Keefe, D.; Kim, C.H.; Laslett, L.J.; Lee, E.P.; Rosenblum, S.S.; Smith, L.; Warwick, A.

    1984-01-01

    The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams. (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to proportional70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units. (orig.)

  5. Operational experience with the Fermilab Linac

    International Nuclear Information System (INIS)

    Allen, L.J.; Lennox, A.J.; Schmidt, C.W.

    1992-01-01

    The Fermilab 200-MeV Linac has been in operation for nearly 22 years as a proton injector to the Booster synchrotron. It presently accelerates H - ions to 200 MeV for charge-exchange injection into the Booster and to 66 MeV for the production of neutrons at the Neutron Therapy Facility (NTF). The beam intensity is typically 35 mA with pulse widths of 30 μsec for the Booster for high energy physics and 57 μsec for NTF at a maximum of 15 pulses per sec. During a typical physics run of nine to twelve months, beam is available for greater than 98% of the scheduled time. The Linac history, operation, tuning, stability and reliability will be discussed. (Author) 15 refs., 2 tabs

  6. Research on backward traveling wave electron linac

    International Nuclear Information System (INIS)

    Chen Huaibi; Zheng Shuxin; Ding Xiaodong; Lin Yuzheng

    1999-01-01

    Future electron linacs require high gradient acceleration. The studies on the high shunt impedance backward traveling wave electron linac accelerating structure (BTW) are presented. At first, the characteristics of BTW are researched. The option of mode and optimal design methods of accelerating cavity for BTW are studied. A physical design method for BTW accelerators, including longitudinal and transversal particle dynamics, is given. Based on above studies, a 9 MeV BTW accelerating tube at 3π/4 mode with frequency 2856 MHz for inspecting large container as radiation source at customs is designed, and a comparison with disk-loaded waveguide accelerating tube is made. The result of research leads to the conclusion that backward traveling wave accelerating structure is preferable. Because BTW has higher effective shunt impedance, shorter filling time and more stable operation

  7. Induction linacs for heavy ion fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Fessenden, T.J.

    1984-05-01

    The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams, (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to approx. 70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units.

  8. Commissioning the Linac Coherent Light Source injector

    Directory of Open Access Journals (Sweden)

    R. Akre

    2008-03-01

    Full Text Available The Linac Coherent Light Source is a SASE x-ray free-electron laser (FEL project presently under construction at SLAC [J. Arthur et al., SLAC-R-593, 2002.]. The injector section, from drive laser and rf photocathode gun through first bunch compressor chicane, was installed in the fall of 2006. The initial system commissioning with an electron beam was completed in August of 2007, with the goal of a 1.2-micron emittance in a 1-nC bunch demonstrated. The second phase of commissioning, including second bunch compressor and full linac, is planned for 2008, with FEL commissioning in 2009. We report experimental results and experience gained in the first phase of commissioning, including the photocathode drive laser, rf gun, photocathode, S-band and X-band rf systems, first bunch compressor, and the various beam diagnostics.

  9. Re-circulating linac vacuum system

    International Nuclear Information System (INIS)

    Wells, Russell P.; Corlett, John N.; Zholents, Alexander A.

    2003-01-01

    The vacuum system for a proposed 2.5 GeV, 10ΜA recirculating linac synchrotron light source [1] is readily achievable with conventional vacuum hardware and established fabrication processes. Some of the difficult technical challenges associated with synchrotron light source storage rings are sidestepped by the relatively low beam current and short beam lifetime requirements of a re-circulating linac. This minimal lifetime requirement leads directly to relatively high limits on the background gas pressure through much of the facility. The 10ΜA average beam current produces very little synchrotron radiation induced gas desorption and thus the need for an ante-chamber in the vacuum chamber is eliminated. In the arc bend magnets, and the insertion devices, the vacuum chamber dimensions can be selected to balance the coherent synchrotron radiation and resistive wall wakefield effects, while maintaining the modest limits on the gas pressure and minimal outgassing

  10. Making electron beams for the SLC linac

    International Nuclear Information System (INIS)

    Clendenin, J.E.; Ecklund, S.D.; James, M.B.; Miller, R.H.; Sheppard, J.C.; Sodja, J.; Truher, J.B.; Minten, A.

    1984-01-01

    A source of high-intensity, single-bunch electron beams has been developed at SLAC for the SLC. The properties of these beams have been studied extensively utilizing the first 100-m of the SLAC linac and the computer-based control system being developed for the SLC. The source is described and the properties of the beams are summarized. 9 references, 2 figures, 1 table

  11. Control system in the technological electron linacs

    International Nuclear Information System (INIS)

    Boriskin, V.N.; Akchurin, Yu.I.; Bahmetev, N.N.; Gurin, V.A.

    1999-01-01

    The special system has been developed for linac control.It controls the electron beam current,the energy and the position,protects the accelerating and scanning systems from the damage caused by the beam;blocks the modulator and the klystron amplifier in the case of intolerable operating modes;regulates the phase and power of the HF signals in the injecting system and also regulates the source power currents in the magnetic system

  12. Beam dynamics in heavy ion induction LINACS

    International Nuclear Information System (INIS)

    Smith, L.

    1981-10-01

    Interest in the use of an induction linac to accelerate heavy ions for the purpose of providing the energy required to initiate an inertially confined fusion reaction has stimulated a theoretical effort to investigate various beam dynamical effects associated with high intensity heavy ion beams. This paper presents a summary of the work that has been done so far; transverse, longitudinal and coupled longitudinal transverse effects are discussed

  13. LINAC for ADS application - accelerator technologies

    International Nuclear Information System (INIS)

    Garnett, Robert W.; Sheffreld, Richard L.

    2009-01-01

    Sifnificant high-current, high-intensity accelerator research and development have been done in the recent past in the US, centered primarily at Los Alamos National Laboratory. These efforts have included designs for the Accelerator Production of Tritium Project, Accelerator Transmutation of Waste, and Accelerator Driven Systems, as well as many others. This past work and some specific design principles that were developed to optimie linac designs for ADS and other high-intensity applications will be discussed briefly.

  14. Thermo mechanical design of normal-conducting deflecting cavities at the Advanced Photon Source for short x-ray pulse generation.

    Energy Technology Data Exchange (ETDEWEB)

    Brajuskovic, B.; Collins, J.; Den Hartog, P.; Morrison, L.; Waldschmidt, G.

    2008-01-01

    A normal-conducting deflecting cavity is being designed at the Advanced Photon Source (APS) as a part of the short x-ray pulse project intended to provide users with approximately 2 picosecond x-rays. The system will use two pairs of 3-cell cavities in sectors 6ID and 7ID for the generation of the x-ray pulse in the 7ID beamline. The 3-cell cavities are designed to provide the desired beam deflection while absorbing in excess of 4 kW of power from a pulsed rf system and up to 2.6 kW in the damper system of high-order mode (HOM) and low-order mode (LOM) waveguides. Since the cavity frequency is very sensitive to thermal expansion, the cooling water system is designed so that it is able to control cavity temperature to within 0.1 C. This paper describes the optimization of the thermomechanical design of the cavity based on calculation of thermal stresses and displacement caused by the generated heat loads, and presents the design of a cooling water system required for the proper operation of the cavities.

  15. LINAC4 takes a tour of Europe

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Along the German Autobahnen, a truck carrying 20 tonnes of copper is on its way to Poland. The metal has already made a short tour of Europe, yet the drive across the high-speed highway is only the beginning of its transformation into CERN’s next linear accelerator, LINAC4.   Grzegorz Wrochna (left), director of the Andrzej Soltan Institute for Nuclear Studies (IPJ), and Rolf Heuer (right), CERN DG, sign the framework agreement between the two institutes. By the summer of 2012, the PI-Mode Structures (PIMS) will be constructed and completely installed in the LINAC4 tunnel. The PIMS cavities are the final accelerating structures needed for LINAC4, and have been designed to accelerate protons from 100 to 160MeV. While the first cavity was built entirely at CERN, construction of the remaining cavities has become a larger, multi-national operation. In a 1 million euro framework agreement signed on 11 February by the Director-General, the Andrzej Soltan Institute for Nuclear Studies in Swie...

  16. The RF system for FELI linac

    International Nuclear Information System (INIS)

    Morii, Y.; Abe, S.; Keishi, T.; Tomimasu, T.

    1995-01-01

    FELI (Free Electron Laser Research Institute, Inc.) is constructing a Free Electron Laser facility covering from 20μm (infra red region) to 0.35μm (ultra violet region), using as S-band linac. The linac consists of a thermoionic 0.5ns-pulse triggered gun, a 714-MHz SHB (subharmonic buncher), a 2856-MHz standing wave type buncher, and seven ETL (Electro-technical Laboratory) type accelerating sections. An RF system of the linac for FELs is required of long pulse duration and high stability. Two S-band klystrons (TOSHIBA E3729) are operated in three pulse operation modes (pulse width and peak RF power): 24μs-24MW, 12.5μs-34MW, 0.5μs-70MW. Each klystron modulator has a PFN consisting of 4 parallel networks of 24 capacitors and 24 variable inductors, and it has a line switch of an optical thyristor stack. An S-band klystron and its modulator were combined to test their performance at the works of NISSIN ELECTRIC Co. in December 1993. These equipments were installed at FELI in January 1994. The design and experimental results of the RF system are summarized in this paper. (author)

  17. Experiments and prospects for induction linac drivers

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-05-01

    In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source

  18. Experiments and prospects for induction linac drivers

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-12-01

    In the last three years, the US program in Heavy Ion Fusion has concentrated on understanding the induction linac approach to a power-plant driver. In this method it is important that the beam current be maximized throughout the accelerator. Consequently, it is crucial to understand the space-charge limit in the AG transport system in the linac and, also, to achieve current amplification during acceleration to keep pace with the kinematical increase of this limit with energy. Experimental results on both these matters and also on the use of multiple beams (inside the same accelerating structure) will be described. A new examination of the most attractive properties of the induction linac for a fusion driver has clearly pointed to the advantage of using heavy ions with a charge-state greater than unity - perhaps q = 3 may be an optimum. This development places even greater importance on understanding space-charge limits and mechanisms for emittance growth; also, it will require a new emphasis on the development of a suitable ion source

  19. Preinjector for Linac 1, Faraday cage

    CERN Multimedia

    1974-01-01

    The 50 MeV Linac 1 started up in 1958 as injector to the 26 GeV PS, with a 520 kV Cockcroft-Walton generator as its preinjector, housed in a vast Faraday cage, visible here. When the Cockcroft-Walton broke down in 1973, it was replaced by a much smaller SAMES generator, of the kind used for electrostatic separators. From 1980 on, Linac 2 took over as injector for the 800 MeV Booster, and Linac 1 continued as injector for LEAR. In 1984, the electrostatic preinjector (i.e. the Faraday cage with its contents, SAMES generator and all) was replaced by a 520 keV RFQ. At the lower left corner we see the HV connectors to the SAMES generator, at the right edge part of the opened electronics-platform. Jean-Luc Vallet sees to it that all parts are properly grounded. See also 7403073X, 7403074X, 7403081X, 7403083X.

  20. All Digital IQ Servo-System for CERN Linacs

    CERN Document Server

    Rohlev, A; Garoby, R

    2003-01-01

    A new VME based system has been developed and built at CERN for the servo loops regulating the field in the linac accelerating structure. It makes use of high speed digital In-phase/Quadrature (IQ) detection, digital processing, and digital IQ modulation. The digital processing and IQ modulation is done in a single PLD. The system incorporates continually variable set points, iterative learning, feed forward as well as extensive diagnostics and other features well suited for digital implementations. Built on a single VME card, it will be first used in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3) and later for upgrading the present proton linac (linac 2). This system serves also as a prototype for the future Superconducting Proton Linac (SPL). The design principle and the experimental results are described.

  1. Preliminary design of a dedicated proton therapy linac

    International Nuclear Information System (INIS)

    Hamm, R.W.; Crandall, K.R.; Potter, J.M.

    1991-01-01

    The preliminary design has been completed for a low current, compact proton linac dedicated to cancer therapy. A 3 GHz side-coupled structure accelerates the beam from a 70 MeV drift tube linac using commercially available S-band rf power systems and accelerating cavities. This significantly reduces the linac cost and allows incremental energies up to 250 MeV. The short beam pulse width and high repetition rate make the linac similar to the high energy electron linacs now used for cancer therapy, yet produce a proton flux sufficient for treatment of large tumors. The high pulse repetition rate permits raster scanning, and the small output beam size and emittance result in a compact isocentric gantry design. Such a linac will reduce the facility and operating costs for a dedicated cancer therapy system

  2. SU-F-J-147: Magnetic Field Dose Response Considerations for a Linac Monitor Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, M; Fallone, B [Cross Cancer Institute, Edmonton, AB (Canada)

    2016-06-15

    Purpose: The impact of magnetic fields on the readings of a linac monitor chamber have not yet been investigated. Herein we examine the total dose response as well as any deviations in the beam parameters of flatness and symmetry when a Varian monitor chamber is irradiated within an applied magnetic field. This work has direct application to the development of Linac-MR systems worldwide. Methods: A Varian monitor chamber was modeled in the Monte Carlo code PENELOPE and irradiated in the presence of a magnetic field with a phase space generated from a model of a Linac-MR prototype system. The magnetic field strength was stepped from 0 to 3.0T in both parallel and perpendicular directions with respect to the normal surface of the phase space. Dose to each of the four regions in the monitor chamber were scored separately for every magnetic field adaptation to evaluate the effect of the magnetic field on flatness and symmetry. Results: When the magnetic field is perpendicular to the phase space normal we see a change in dose response with a maximal deviation (10–25% depending on the chamber region) near 0.75T. In the direction of electron deflection we expectedly see opposite responses in chamber regions leading to a measured asymmetry. With a magnetic field parallel to the phase space normal we see no measured asymmetries, however there is a monotonic rise in dose response leveling off at about +12% near 2.5T. Conclusion: Attention must be given to correct for the strength and direction of the magnetic field at the location of the linac monitor chamber in hybrid Linac-MR devices. Elsewise the dose sampled by these chambers may not represent the actual dose expected at isocentre; additionally there may be a need to correct for the symmetry of the beam recorded by the monitor chamber. Fallone is a co-founder and CEO of MagnetTx Oncology Solutions (under discussions to license Alberta bi-planar linac MR for commercialization).

  3. RESONANCE CONTROL FOR THE COUPLED CAVITY LINAC AND DRIFT TUBE LINAC STRUCTURES OF THE SPALLATION NEUTRON SOURCE LINAC USING A CLOSED-LOOP WATER COOLING SYSTEM

    International Nuclear Information System (INIS)

    Bernardin, J.D.; Brown, R.L.

    2001-01-01

    The Spallation Neutron Source (SNS) is a facility being designed for scientific and industrial research and development. SNS will generate and use neutrons as a diagnostic tool for medical purposes, material science, etc. The neutrons will be produced by bombarding a heavy metal target with a high-energy beam of protons, generated and accelerated with a linear particle accelerator, or linac. The low energy end of the linac consists of two room temperature copper structures, the drift tube linac (DTL), and the coupled cavity linac (CCL). Both of these accelerating structures use large amounts of electrical energy to accelerate the protons to an energy of 185 MeV. Approximately 60-80% of the electrical energy is dissipated in the copper structure and must be removed. This is done using specifically designed water cooling passages within the linac's copper structure. Cooling water is supplied to these cooling passages by specially designed resonance control and water cooling systems

  4. Effect of the transverse parasitic mode on beam performance for the ADS driver linac in China

    International Nuclear Information System (INIS)

    Cheng Peng; Pei Shilun; Wang Jiuqing; Li Zhihui

    2015-01-01

    The ADS (Accelerator Driven subcritical System) driver linac in China is designed to run in CW (Continuous Wave) mode with 10 mA designed beam current. In this scenario, the beam-induced parasitic modes in the ADS driver linac may make the beam unstable or deteriorate the beam performance. To evaluate the parasitic mode effect on the beam dynamics systematically, simulation studies using the ROOT-based numerical code SMD have been conducted. The longitudinal beam instability induced by the HOMs (High Order Modes) and SOMs (Same Order Modes) has little effect on the longitudinal beam performance for the current ADS driver linac design based on the 10 MeV/325 MHz injector I from previous studies. Here the transverse parasitic mode (i.e., dipole HOM) effect on the transverse beam performance at the ADS driver linac exit is investigated. To more reasonably quantify the dipole mode effect, the multi-bunch effective emittance is introduced in this paper. (authors)

  5. A 2--4 nm Linac Coherent Light Source (LCLS) using the SLAC linac

    International Nuclear Information System (INIS)

    Winick, H.; Bane, K.; Boyce, R.

    1993-05-01

    We describe the use of the SLAC linac to drive a unique, powerful. short wavelength Linac Coherent Light Source (LCLS). Operating as an FEL, lasing would be achieved in a single pass of a high peak current electron beam through a long undulator by self-amplified spontaneous emission (SASE). The main components are a high-brightness rf photocathode electron gun; pulse compressors; about 1/5 of the SLAC linac; and a long undulator with a FODO quadrupole focussing system. Using electrons below 8 GeV, the system would operate at wavelengths down to about 3 nm, producing ≥10 GW peak power in sub-ps pulses. At a 120 Hz rate the average power is ∼ 1 W

  6. S-band linac-based X-ray source with {pi}/2-mode electron linac

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Abhay, E-mail: abhay@post.kek.jp [Department of Accelerator Science, School of High Energy Accelerator Science, Graduate University for Advanced Studies, Shonan International Village, Hayama, Miura, Kanagawa 240-0193 (Japan); Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Araki, Sakae [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Dixit, Tanuja [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Fukuda, Masafumi [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Krishnan, R; Pethe, Sanjay [Society for Applied Microwave Electronic Engineering and Research (SAMEER), R and D Laboratory of the Government of India, IIT Campus, Powai, Mumbai 400 076 (India); Sakaue, Kazuyuki [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan); Terunuma, Nobuhiro; Urakawa, Junji [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Washio, Masakazu [Waseda University, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2011-05-01

    The activities with the compact X-ray source are attracting more attention, particularly for the applications of the source in medical fields. We propose the fabrication of a compact X-ray source using the SAMEER electron linear accelerator and the KEK laser undulator X-ray source (LUCX) technologies. The linac developed at SAMEER is a standing wave side-coupled S-band linac operating in the {pi}/2 mode. In the proposed system, a photocathode RF gun will inject bunches of electrons in the linac to accelerate and achieve a high-energy, low-emittance beam. This beam will then interact with the laser in the laser cavity to produce X-rays of a type well suited for various applications. The side-coupled structure will make the system more compact, and the {pi}/2 mode of operation will enable a high repetition rate operation, which will help to increase the X-ray yield.

  7. Wire scanner data analysis for the SSC Linac emittance measurement

    International Nuclear Information System (INIS)

    Yao, C.Y.; Hurd, J.W.; Sage, J.

    1993-07-01

    The wire scanners are designed in the SSC Linac for measurement of beam emittance at various locations. In order to obtain beam parameters from the scan signal, a data analysis program was developed that considers the problems of noise reduction, machine modeling, parameter fitting, and correction. This program is intended as a tool for Linac commissioning and also as part of the Linac control program. Some of the results from commissioning runs are presented

  8. Design of 6 MeV X-band electron linac for dual-head gantry radiotherapy system

    Science.gov (United States)

    Shin, Seung-wook; Lee, Seung-Hyun; Lee, Jong-Chul; Kim, Huisu; Ha, Donghyup; Ghergherehchi, Mitra; Chai, Jongseo; Lee, Byung-no; Chae, Moonsik

    2017-12-01

    A compact 6 MeV electron linac is being developed at Sungkyunkwan University, in collaboration with the Korea atomic energy research institute (KAERI). The linac will be used as an X-ray source for a dual-head gantry radiotherapy system. X-band technology has been employed to satisfy the size requirement of the dual-head gantry radiotherapy machine. Among the several options available, we selected a pi/2-mode, standing-wave, side-coupled cavity. This choice of radiofrequency (RF) cavity design is intended to enhance the shunt impedance of each cavity in the linac. An optimum structure of the RF cavity with a high-performance design was determined by applying a genetic algorithm during the optimization procedure. This paper describes the detailed design process for a single normal RF cavity and the entire structure, including the RF power coupler and coupling cavity, as well as the beam dynamics results.

  9. Crossbar H-mode drift-tube linac design with alternative phase focusing for muon linac

    Science.gov (United States)

    Otani, M.; Futatsukawa, K.; Hasegawa, K.; Kitamura, R.; Kondo, Y.; Kurennoy, S.

    2017-07-01

    We have developed a Crossbar H-mode (CH) drift-tube linac (DTL) design with an alternative phase focusing (APF) scheme for a muon linac, in order to measure the anomalous magnetic moment and electric dipole moment (EDM) of muons at the Japan Proton Accelerator Research Complex (J-PARC). The CH-DTL accelerates muons from β = v/c = 0.08 to 0.28 at an operational frequency of 324 MHz. The design and results are described in this paper.

  10. Linac4: the final assembly stage is under way

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    The Linac4 radiofrequency quadrupole (RFQ) module was installed at the accelerator test-stand in Building 152 last August. After an assembly phase and tests that concluded last March with the acceleration of a hydrogen beam to 3 MeV, the module has just been permanently installed in the new Linac4 tunnel (Building 400). The installation of the MEBT (Medium Energy Beam Transport) will begin shortly, followed by the start of the first Linac4 commissioning phase.     To find out more about the Linac4 RFQ module, read the previous Bulletin articles published in Nos. 21-22/2010 and 35-36/2012.

  11. Oxygen ion source and RFQ for Linac 1

    CERN Multimedia

    Photographic Service

    1986-01-01

    As injector to the PS Booster, Linac 1 was replaced by Linac 2 in 1980. It continued to be used for the acceleration of oxygen and sulfur ions. In 1984, its Cockcroft-Walton preinjector was replaced by an RFQ. In the foreground at the right is the oxygen ion source. A 90 deg bending magnet selects O6+ ions which are preaccelerated in an RFQ and enter Linac 1, at the far left. In the background is the proton and negative hydrogen ion source, followed by the 520 keV RFQ-1 and a bending magnet towards the entrance of Linac 1.

  12. Two-pulse acceleration for BEPCII injector linac

    International Nuclear Information System (INIS)

    Pei Shilun; Wang Shuhong; Lu Weibin

    2007-01-01

    In order to double the injection rate of positron beam from the linac to the storage ring of BEPC II, a two-pulse generation and acceleration scheme has been proposed. The two-pulse simulation by programs including LIAR, PARMELA, EGUN and TRANSPORT is described first and the method is applied in the beam dynamics studies of BEPC II linac. The experiment of two-pulse acceleration was performed in BEPC II linac and some preliminary results are obtained, which provides a good reference for further upgrading of BEPC II injector linac. (authors)

  13. Upgrade of the controls for the Brookhaven linac

    International Nuclear Information System (INIS)

    Buxton, W.E.

    1995-01-01

    The control of the magnets, rf system, and other components at the Brookhaven Linac uses a system that was developed at Brookhaven in the late 1960's. This system will be retired in the summer of 1995. The Linac controls are being upgraded using modem VME-based hardware compatible with RHIC generation controls, and an existing serial field bus. The timing for the Linac will also be upgraded and will use components developed for RHIC. The controls in general, the timing for the Linac, and the modules developed will be described

  14. All Digital IQ Servo-System for CERN Linacs

    CERN Document Server

    Broere, J; Garoby, R; Rohlev, A; Serrano, J

    2004-01-01

    A VME based control system has been developed and built at CERN for the servo loops regulating the field in linac accelerating structures. It is an all-digital system built on a single VME card, providing digital detection, processing, and modulation. It is foreseen to be used, in different versions, for the needs of both present and future CERN hadron linacs. The first application will be in the energy ramping RF chain of the CERN Heavy Ion Linac (linac 3). Design principle and the experimental results are described.

  15. Improved temperature regulation of APS linac RF components

    International Nuclear Information System (INIS)

    Dortwegt, R.

    1998-01-01

    The temperature of the APS S-Band linac's high-power rf components is regulated by water from individual closed-loop deionized (DI) water systems. The rf components are all made of oxygen-free high-conductivity copper and respond quickly to temperature changes. The SLED cavities are especially temperature-sensitive and cause beam energy instabilities when the temperature is not well regulated. Temperature regulation better than ± 0.1 F is required to achieve good energy stability. Improvements in the closed-loop water systems have enabled them to achieve a regulation of ± 0.05 F over long periods. Regulation philosophy and equipment are discussed and numerical results are presented

  16. Development of an RFQ linac for unstable nuclei

    International Nuclear Information System (INIS)

    Arai, S.; Imanishi, A.; Morimoto, T.; Shibuya, S.; Tojyo, E.; Tokuda, N.

    1990-05-01

    A split coaxial RFQ (SCRFQ) is being developed for accelerating unstable nuclei with a charge-to-mass ratio larger than 1/60 from 1 to 170 keV/u in the JHP heavy-ion linac. The SCRFQ is equipped with modulated vanes to generate ideal quadrupole and accelerating fields. The fundamental problems on the SCRFQ have been clarified and solved through studies on a cold model, and the excellent accelerating performance has been confirmed by using a proton accelerating model working at 50 MHz. A 25.5-MHz prototype for the JHP SCRFQ is now under development. The prototype, 2.1 m in length and 0.9 m in diameter, will accelerate ions with a charge-to-mass ratio larger than 1/30 from 1 to 45 keV/u. Low-power tests conducted so far show that the prototype cavity has good rf characteristics. (author)

  17. WE-G-17A-09: Novel Magnetic Shielding Design for Inline and Perpendicular Integrated 6 MV Linac and 1.0 T MRI Systems

    Energy Technology Data Exchange (ETDEWEB)

    Li, X; Ma, B; Kuang, Y [University of Nevada, Las Vegas, Las Vegas, NV (United States); Diao, X [Shenzhen University, Shenzhen, Guangdong (China)

    2014-06-15

    Purpose: The influence of fringe magnetic fields delivered by magnetic resonance imaging (MRI) on the beam generation and transportation in Linac is still a major challenge for the integration of linear accelerator and MRI (Linac-MRI). In this study, we investigated an optimal magnetic shielding design for Linac-MRI and further characterized the beam trajectory in electron gun. Methods: Both inline and perpendicular configurations were analyzed in this study. The configurations, comprising a Linac-MRI with a 100cm SAD and an open 1.0 T superconductive magnet, were simulated by the 3D finite element method (FEM). The steel shielding around the Linac was included in the 3D model, the thickness of which was varied from 1mm to 20mm, and magnetic field maps were acquired with and without additional shielding. The treatment beam trajectory in electron gun was evaluated using OPERA 3d SCALA with and without shielding cases. Results: When Linac was not shielded, the uniformity of diameter sphere volume (DSV) (30cm) was about 5 parts per million (ppm) and the fringe magnetic fields in electron gun were more than 0.3 T. With shielding, the magnetic fields in electron gun were reduced to less than 0.01 T. For the inline configuration, the radial magnetic fields in the Linac were about 0.02T. A cylinder steel shield used (5mm thick) altered the uniformity of DSV to 1000 ppm. For the perpendicular configuration, the Linac transverse magnetic fields were more than 0.3T, which altered the beam trajectory significantly. A 8mm-thick cylinder steel shield surrounding the Linac was used to compensate the output losses of Linac, which shifted the magnetic fields' uniformity of DSV to 400 ppm. Conclusion: For both configurations, the Linac shielding was used to ensure normal operation of the Linac. The effect of magnetic fields on the uniformity of DSV could be modulated by the shimming technique of the MRI magnet. NIH/NIGMS grant U54 GM104944, Lincy Endowed Assistant

  18. WE-G-17A-09: Novel Magnetic Shielding Design for Inline and Perpendicular Integrated 6 MV Linac and 1.0 T MRI Systems

    International Nuclear Information System (INIS)

    Li, X; Ma, B; Kuang, Y; Diao, X

    2014-01-01

    Purpose: The influence of fringe magnetic fields delivered by magnetic resonance imaging (MRI) on the beam generation and transportation in Linac is still a major challenge for the integration of linear accelerator and MRI (Linac-MRI). In this study, we investigated an optimal magnetic shielding design for Linac-MRI and further characterized the beam trajectory in electron gun. Methods: Both inline and perpendicular configurations were analyzed in this study. The configurations, comprising a Linac-MRI with a 100cm SAD and an open 1.0 T superconductive magnet, were simulated by the 3D finite element method (FEM). The steel shielding around the Linac was included in the 3D model, the thickness of which was varied from 1mm to 20mm, and magnetic field maps were acquired with and without additional shielding. The treatment beam trajectory in electron gun was evaluated using OPERA 3d SCALA with and without shielding cases. Results: When Linac was not shielded, the uniformity of diameter sphere volume (DSV) (30cm) was about 5 parts per million (ppm) and the fringe magnetic fields in electron gun were more than 0.3 T. With shielding, the magnetic fields in electron gun were reduced to less than 0.01 T. For the inline configuration, the radial magnetic fields in the Linac were about 0.02T. A cylinder steel shield used (5mm thick) altered the uniformity of DSV to 1000 ppm. For the perpendicular configuration, the Linac transverse magnetic fields were more than 0.3T, which altered the beam trajectory significantly. A 8mm-thick cylinder steel shield surrounding the Linac was used to compensate the output losses of Linac, which shifted the magnetic fields' uniformity of DSV to 400 ppm. Conclusion: For both configurations, the Linac shielding was used to ensure normal operation of the Linac. The effect of magnetic fields on the uniformity of DSV could be modulated by the shimming technique of the MRI magnet. NIH/NIGMS grant U54 GM104944, Lincy Endowed Assistant

  19. LINAC-radiosurgery for nonsecreting pituitary adenomas. Long-term results

    Energy Technology Data Exchange (ETDEWEB)

    Runge, M.J.R.; Maarouf, M.; Hunsche, S.; Ruge, M.I.; El Majdoub, F.; Treuer, H.; Sturm, V. [Koeln Univ. (Germany). Dept. of Stereotaxy and Functional Neurosurgery; Kocher, M.; Mueller, R.P. [Koeln Univ. (Germany). Dept. of Radiation Oncology; Voges, J. [Magdeburg Univ. (Germany). Dept. of Stereotactic Neurosurgery

    2012-04-15

    Stereotactic linear accelerator-based radiosurgery (LINAC-RS) is increasingly used for microsurgically inaccessible or recurrent pituitary adenomas. This single-center study evaluates the long-term follow-up after LINAC-RS of nonsecreting pituitary adenomas (NSA). Patients and methods: Between 1992 and August 2008, 65 patients with NSA were treated. Patient treatment and follow-up were conducted according to a prospective protocol. Indications for LINAC-RS were (1) tumor recurrence or (2) residual tumor. Three patients were treated primarily. For analysis of prognostic factors, patients were grouped according to epidemiological or treatment-associated characteristics. Results: A total of 61 patients with a follow-up {>=} 12 months (median 83 months, range 15-186 months, longest follow-up of published radiosurgery series) were evaluated with regard to their clinical, radiological, and endocrinological course. The median tumor volume was 3.5 ml ({+-} 4.3 ml, range 0.3-17.3 ml) treated with a median surface and maximum dose of 13.0 Gy and 29.7 Gy, respectively. Local tumor control was achieved in 98%. One patient died of unrelated cause after 36 months and 1 patient developed a radiation-induced seizure disorder. Visual complications did not occur. In 37 of 41 patients (90.2%), pituitary function remained stable. Maximum dose to the pituitary {<=} 16 Gy and female gender were positive prognostic factors for the preservation of pituitary function. Conclusion: LINAC-RS is a minimally invasive, safe, and effective treatment for recurrent NSA or microsurgically inaccessible residual tumor. LINAC-RS yielded a high rate of local long-term tumor control with a small number of radiation-induced side effects. (orig.)

  20. LINAC-radiosurgery for nonsecreting pituitary adenomas. Long-term results

    International Nuclear Information System (INIS)

    Runge, M.J.R.; Maarouf, M.; Hunsche, S.; Ruge, M.I.; El Majdoub, F.; Treuer, H.; Sturm, V.; Kocher, M.; Mueller, R.P.; Voges, J.

    2012-01-01

    Stereotactic linear accelerator-based radiosurgery (LINAC-RS) is increasingly used for microsurgically inaccessible or recurrent pituitary adenomas. This single-center study evaluates the long-term follow-up after LINAC-RS of nonsecreting pituitary adenomas (NSA). Patients and methods: Between 1992 and August 2008, 65 patients with NSA were treated. Patient treatment and follow-up were conducted according to a prospective protocol. Indications for LINAC-RS were (1) tumor recurrence or (2) residual tumor. Three patients were treated primarily. For analysis of prognostic factors, patients were grouped according to epidemiological or treatment-associated characteristics. Results: A total of 61 patients with a follow-up ≥ 12 months (median 83 months, range 15-186 months, longest follow-up of published radiosurgery series) were evaluated with regard to their clinical, radiological, and endocrinological course. The median tumor volume was 3.5 ml (± 4.3 ml, range 0.3-17.3 ml) treated with a median surface and maximum dose of 13.0 Gy and 29.7 Gy, respectively. Local tumor control was achieved in 98%. One patient died of unrelated cause after 36 months and 1 patient developed a radiation-induced seizure disorder. Visual complications did not occur. In 37 of 41 patients (90.2%), pituitary function remained stable. Maximum dose to the pituitary ≤ 16 Gy and female gender were positive prognostic factors for the preservation of pituitary function. Conclusion: LINAC-RS is a minimally invasive, safe, and effective treatment for recurrent NSA or microsurgically inaccessible residual tumor. LINAC-RS yielded a high rate of local long-term tumor control with a small number of radiation-induced side effects. (orig.)

  1. An induction linac injector for scaled experiments

    International Nuclear Information System (INIS)

    Rutkowski, H.L.; Faltens, A.; Pike, C.; Brodzik, D.; Johnson, R.M.; Vanecek, D.; Hewett, D.W.

    1991-04-01

    An injector is being developed at LBL that would serve as the front end of a scaled induction linac accelerator technology experiment for heavy ion fusion. The ion mass being used is in the range 10--18. It is a multi-beam device intended to accelerate up to 2 MeV with 500 mA in each beam. The first half of the accelerating column has been built and experiments with one carbon beam are underway at the 1 MeV level. 5 refs., 1 fig

  2. Laser system for a subpicosecond electron linac

    International Nuclear Information System (INIS)

    Crowell, R. A.

    1998-01-01

    At the Argonne Chemistry Division efforts are underway to develop a sub-picosecond electron beam pulse radiolysis facility for chemical studies. The target output of the accelerator is to generate electron pulses that can be adjusted from 3nC in .6ps to 100nC in 45ps. In conjunction with development of the accelerator a state-of-the-art ultrafast laser system is under construction that will drive the linac's photocathode and provide probe pulses that are tunable from the UV to IR spectral regions

  3. A new RFQ linac fabrication technique

    International Nuclear Information System (INIS)

    Schrage, D.; Roybal, P.; Young, L.; Clark, W.; DePaula, R.; Martinez, F.

    1994-01-01

    The use of hydrogen furnace brazing has been applied as a joining technology to the fabrication of a Radio-Frequency-Quadrupole (RFQ) linac for the Los Alamos Accelerator Performance Demonstration Facility (APDF). The design concept provides a monolithic cavity with no longitudinal rf, vacuum, or mechanical joints. A 530 MHz, 0.46 meter long engineering model RFQ has been fabricated and tested at the Los Alamos National Laboratory as a technical demonstration of this concept. It is planned that two funneled RFQ's for the APDF (7 MeV, 350 MHz, 100 mAmp CW, each eight meters in length) will be manufactured by this method

  4. High power CW linac in PNC

    International Nuclear Information System (INIS)

    Toyama, S.; Wang, Y.L.; Emoto, T.

    1994-01-01

    Power Reactor and Nuclear Fuel Development Corporation (PNC) is developing a high power electron linac for various applications. The electron beam is accelerated in CW operation to get maximum beam current of 100 mA and energy of 10 MeV. Crucial components such as a high power L-band klystron and a high power traveling wave resonant ring (TWRR) accelerator guides were designed and manufactured and their performance were examined. These design and results from the recent high power RF tests were described in this paper. (author)

  5. Contraband detection technological complex with ion linac

    International Nuclear Information System (INIS)

    Gavrish, Yu.N.; Svistunov, Yu.A.; Sidorov, A.V.

    2004-01-01

    The contraband detection technological complex (CDTC) to detect explosives, fission materials, and vegetable drugs is proposed. Our approach employs the pulsed neutron source. The CDTC employs the rf linac to provide a beam of deuterons of 1 or 3.5 MeV, which impinge upon a target giving birth pulsed neutron flow. Explosives are identified by the matrix detection system with gamma registration under interaction of neutron on N, O, C nuclei. Experimental verification of main principles of matrix detection system is presented

  6. Fermilab linac upgrade. Module conditioning results

    International Nuclear Information System (INIS)

    Kroc, T.; Moretti, A.; Popovic, M.

    1992-01-01

    The 805 MHz side-coupled cavity modules for the Fermilab 400 MeV linac upgrade have been conditioned to accept full power. The sparking rate in the cavities and in the side cells has been reduced to acceptable levels. It required approximately 40 x 10 6 pulses for each module to achieve an adequately low sparking rate. This contribution outlines the commissioning procedure, presents the sparking rate improvements and the radiation level improvements through the commissioning process and discusses the near-on-line commissioning plans for this accelerator. (Author) ref., 4 figs

  7. Fermilab Linac Upgrade: Module conditioning results

    International Nuclear Information System (INIS)

    Kroc, T.; Moretti, A.; Popovic, M.

    1992-12-01

    The 805 MHz Side-coupled cavity modules for the Fermilab 400 MeV linac upgrade have been conditioned to accept full power. The sparking rate in the cavities and in the side-cells has been reduced to acceptable levels. It required approximately 40 x 10 6 pulses for each module to achieve an adequately low sparking rate. This contribution outlines the commissioning procedure, presents the sparking rate improvements and the radiation level improvements through the commissioning process and disc the near-online commissioning plans for this accelerator

  8. High density harp for SSCL linac

    International Nuclear Information System (INIS)

    Fritsche, C.T.; Krogh, M.L.; Crist, C.E.

    1993-01-01

    AlliedSignal Inc., Kansas City Division, and the Superconducting Super Collider Laboratory (SSCL) are collaboratively developing a high density harp for the SSCL linac. This harp is designed using hybrid microcircuit (HMC) technology to obtain a higher wire density than previously available. The developed harp contains one hundred twenty-eight 33-micron-diameter carbon wires on 0.38-mm centers. The harp features an onboard broken wire detection circuit. Carbon wire preparation and attachment processes were developed. High density surface mount connectors were located. The status of high density harp development will be presented along with planned future activities

  9. High density harp for SSCL linac

    International Nuclear Information System (INIS)

    Fritsche, C.T.; Krogh, M.L.

    1993-05-01

    AlliedSignal Inc., Kansas City Division, and the Superconducting Super Collider Laboratory (SSCL) are collaboratively developing a high density harp for the SSCL linac. This harp is designed using hybrid microcircuit (HMC) technology to obtain a higher wire density than previously available. The developed harp contains one hundred twenty-eight 33-micron-diameter carbon wires on 0.38-mm centers. The harp features an onboard broken wire detection circuit. Carbon wire preparation and attachment processes were developed. High density surface mount connectors were located. The status of high density harp development will be presented along with planned future activities

  10. Event Registration System for INR Linac

    International Nuclear Information System (INIS)

    Grekhov, O.V.; Drugakov, A.N.; Kiselev, Yu.V.

    2006-01-01

    The software of the Event registration system for the linear accelerators is described. This system allows receiving of the information on changes of operating modes of the accelerator and supervising of hundreds of key parameters of various systems of the accelerator. The Event registration system consists of the source and listeners of events. The sources of events are subroutines built in existing ACS Linac. The listeners of events are software Supervisor and Client ERS. They are used for warning the operator about change controlled parameter of the accelerator

  11. Superconducting radiofrequency linac development at Fermilab

    International Nuclear Information System (INIS)

    Holmes, Stephen D.

    2009-01-01

    As the Fermilab Tevatron Collider program draws to a close, a strategy has emerged of an experimental program built around the high intensity frontier. The centerpiece of this program is a superconducting H- linac that will support world leading programs in long baseline neutrino experimentation and the study of rare processes. Based on technology shared with the International Linear Collider, Project X will provide multi-MW beams at 60-120 GeV from the Main Injector, simultaneous with very high intensity beams at lower energies. Project X also supports development of a Muon Collider as a future facility at the energy frontier.

  12. Model measurements for the switched power linac

    International Nuclear Information System (INIS)

    Aronson, S.; Caspers, F.; Haseroth, H.; Knott, J.; Willis, W.

    1987-01-01

    To study some aspects of the structure of the switched power linac (or wakefield transformer), a scaled-up model with 2.4 m diameter has been built. Measurements were performed with real-time and synthetic pulses with spectral components up to 5 GHz. Results are obtained for the achievable transformer ratio as a function of the spectral composition of the pulses and for the influence of discrete feeding at the circumference of the transformer disk. The effects of asymmetric feeding in space and time were also investigated experimentally as well as the influence of the central geometry

  13. Survey of vibration amplitudes throughout the linac

    International Nuclear Information System (INIS)

    Werner, K.L.

    1984-01-01

    The magnitude of vibrations of the Linac structure due to on site disturbances, such as cooling towers, pumps, generators, Highway 280 overpass traffic, is of interest. CN-263, for example, discusses tolerances of random (i.e., uncorrelated) quad jitter and suggests that amplitudes should not exceed 0.7 microns rms. This note describes the results of a series of measurements carried out in the summer of 1983. In general, the tolerance is not exceeded, but there appears not to be a good safety factor at low frequencies

  14. Induction linac drivers for commercial heavy-ion beam fusion

    International Nuclear Information System (INIS)

    Keefe, D.

    1987-11-01

    This paper discusses induction linac drivers necessary to accelerate heavy ions at inertial fusion targets. Topics discussed are: driver configurations, the current-amplifying induction linac, high current beam behavior and emittance growth, new considerations for driver design, the heavy ion fusion systems study, and future studies. 13 refs., 6 figs., 1 tab

  15. Properties of heavy ion linacs with alternating phase focusing

    International Nuclear Information System (INIS)

    Deitinghoff, H.; Junior, P.; Klein, H.

    1976-01-01

    General aspects for the application of alternating phase focusing are discussed. The results demand necessary linac parameters. The possibility of their accomplishment by already existing or feasible linac structures with acceleration rates of 2 - 3 MV/m will be considered

  16. Production of slow-positron beams with an electron linac

    International Nuclear Information System (INIS)

    Howell, R.H.; Alvarez, R.A.; Stanek, M.

    1982-01-01

    Intense, pulsed beams of low-energy positrons have been produced by a high-energy beam from an electron linac. The production efficiency for low-energy positrons has been determined for electrons with 60 to 120 MeV energy, low-energy positron beams from a linac can be of much higher intensity than those beams currently derived from radioactive sources

  17. MEIC Proton Beam Formation with a Low Energy Linac

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuhong [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    The MEIC proton and ion beams are generated, accumulated, accelerated and cooled in a new green-field ion injector complex designed specifically to support its high luminosity goal. This injector consists of sources, a linac and a small booster ring. In this paper we explore feasibility of a short ion linac that injects low-energy protons and ions into the booster ring.

  18. Compensated linac beam colliding with a stored beam

    International Nuclear Information System (INIS)

    Csonka, P.L.; Oregon Univ., Eugene

    1981-01-01

    The disruptive effect of a linac beam on a beam circulating in a storage ring can be reduced by compensating for the space charge of the linac beam with a beam which is oppositely charged, may have different bunchlength as well as lower energy, and need not be circulating in a storage ring. (orig.)

  19. Characteristics of short pulse grid pulser for an electron LINAC

    International Nuclear Information System (INIS)

    Wang Guicheng; Fang Zhigao; Hong Jun

    1996-01-01

    An equivalent circuit is used to obtain the output waveform of a short pulse grid pulser for an electron LINAC, and the amplitude of the output pulse is studied as a function of number of switching transistors for some kinds of transistor. Two pulsers were fabricated to fulfill the requirements of the 200 MeV LINAC at NSRL

  20. Development of an Eddy Current Septum for LINAC4

    CERN Document Server

    Barnes, M; Borburgh, J; Fowler, T; Goddard, B; Ueda, A; Weterings, W

    2008-01-01

    A linear accelerator (linac) is the first stage of the CERN accelerator complex. The linac defines the beam quality for subsequent stages of acceleration and the reliability has to be high as a fault of the linac shuts down all other machines. The existing linacs at CERN were designed 30 or more years ago: recent upgrades allowed the linacs to reach LHC requirements but also showed that they are at the limit of their brightness and intensity capabilities. A replacement Superconducting Proton Linac (SPL) has been proposed; the initial part of the SPL is termed LINAC4. The LINAC4 injection bump would be made up of a set of four pulsed dipole magnets; the first of these magnets (BS1) must act as a septum with a thin element dividing the high-field region of the circulating beam from the field-free region through which injected $H^{-}$ beam must pass. The initial specifications for BS1 required; a deflection of 66 mrad at 160 MeV, achieved with a peak field of 628 mT and a length of 250 mm: the field fall time wa...

  1. Design of the SLC damping ring to linac transport lines

    International Nuclear Information System (INIS)

    Fieguth, T.H.; Murray, J.J.

    1983-07-01

    The first and second order optics for the damping ring to linac transport line are designed to preserve the damped transverse emittance while simultaneously compressing the bunch length of the beam to that length required for reinjection into the linac. This design, including provisions for future control of beam polarization, is described

  2. A Pencil Beam for the Linac4 commissioning

    CERN Document Server

    Lallement, JB

    2010-01-01

    In order to characterize the different accelerating structures and transport lines of Linac4 and to proceed to its commissioning, we need to produce a low current, low emittance beam. This note describes the generation of two pencil beams and their dynamic through the Linac.

  3. Development and performance test of a new high power RF window in S-band PLS-II LINAC

    Science.gov (United States)

    Hwang, Woon-Ha; Joo, Young-Do; Kim, Seung-Hwan; Choi, Jae-Young; Noh, Sung-Ju; Ryu, Ji-Wan; Cho, Young-Ki

    2017-12-01

    A prototype of RF window was developed in collaboration with the Pohang Accelerator Laboratory (PAL) and domestic companies. High power performance tests of the single RF window were conducted at PAL to verify the operational characteristics for its application in the Pohang Light Source-II (PLS-II) linear accelerator (Linac). The tests were performed in the in-situ facility consisting of a modulator, klystron, waveguide network, vacuum system, cooling system, and RF analyzing equipment. The test results with Stanford linear accelerator energy doubler (SLED) have shown no breakdown up to 75 MW peak power with 4.5 μs RF pulse width at a repetition rate of 10 Hz. The test results with the current operation level of PLS-II Linac confirm that the RF window well satisfies the criteria for PLS-II Linac operation.

  4. Error studies for SNS Linac. Part 1: Transverse errors

    International Nuclear Information System (INIS)

    Crandall, K.R.

    1998-01-01

    The SNS linac consist of a radio-frequency quadrupole (RFQ), a drift-tube linac (DTL), a coupled-cavity drift-tube linac (CCDTL) and a coupled-cavity linac (CCL). The RFQ and DTL are operated at 402.5 MHz; the CCDTL and CCL are operated at 805 MHz. Between the RFQ and DTL is a medium-energy beam-transport system (MEBT). This error study is concerned with the DTL, CCDTL and CCL, and each will be analyzed separately. In fact, the CCL is divided into two sections, and each of these will be analyzed separately. The types of errors considered here are those that affect the transverse characteristics of the beam. The errors that cause the beam center to be displaced from the linac axis are quad displacements and quad tilts. The errors that cause mismatches are quad gradient errors and quad rotations (roll)

  5. The Pre-Injector Linac for the Diamond Light Source

    CERN Document Server

    Christou, C

    2004-01-01

    The Diamond Light Source is a new medium-energy high brightness synchrotron light facility which is under construction on the Rutherford Appleton Laboratory site in the U.K. The accelerator facility can be divided into three major components; a 3 GeV 561 m circumference storage ring, a full-energy booster synchrotron and a 100 MeV pre-injector linac. This paper describes the linac design and plans for operation. The linac is supplied by ACCEL Instruments GmbH under a turn-key contract, with Diamond Light Source Ltd. providing linac beam diagnostics, control system hardware and standard vacuum components. Commissioning of the linac will take place in early 2005 and user operation of the facility will commence in 2007.

  6. Photon and photoneutron spectra produced in radiotherapy Linacs

    International Nuclear Information System (INIS)

    Vega C, H. R.; Martinez O, S. A.; Benites R, J. L.; Lallena, A. M.

    2011-10-01

    A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10 -6 and 1 MeV. Neutron and Bremsstrahlung spectra show the same features regardless of the linac voltage. The amount of photons and neutrons produced by the 15 MV linac is smaller than that found for the 18 MV linac. As expected, Bremsstrahlung spectra ends according to the voltage used to accelerate the electrons. (Author)

  7. Stabilization of the RF system at the SPring-8 linac

    CERN Document Server

    Asaka, T; Hori, T; Kobayashi, T; Mizuno, A; Sakaki, H; Suzuki, S; Taniuchi, T; Yanagida, K; Yokomizo, H; Yoshikawa, H

    2002-01-01

    Beam energy variation of the SPring-8 linac was 1% or more at the start of beam commissioning. Depending on fluctuation, beam transmission efficiency from the linac to the booster synchrotron was significantly affected, and beam intensity in the booster synchrotron changed 20-30%. This caused delay of optimization of the various parameters in the booster synchrotron. More problematic, the beam intensities stored in each RF (radio frequency) bucket of the storage ring at SPring-8 were all different from each other. The users utilizing synchrotron radiation requested that the beam intensity in each RF bucket be as uniform as possible. It was thus a pressing necessity to stabilize the beam energy in the linac. Investigation of the cause has clarified that the various apparatuses installed in the linac periodically changed depending on circumstances and utilities such as the air conditioner, cooling water and electric power. After various improvements, beam energy stability in the linac of <0.06% rms was attai...

  8. Photon and photoneutron spectra produced in radiotherapy Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Martinez O, S. A. [Universidad Pedagogica y Tecnologica de Colombia, Grupo de Fisica Nuclear Aplicada y Simulacion, Av. Central del Norte Km. 1, Via Paipa Tunja, Boyaca (Colombia); Benites R, J. L. [Universidad Autonoma de Nayarit, Postgrado CBAP, Carretera Tepic Compostela Km. 9, Xalisco, Nayarit (Mexico); Lallena, A. M., E-mail: fermineutron@yahoo.com [Universida de Granada, Departamento de Fisica Atomica, Molecular y Nuclear, E-18071 Granada (Spain)

    2011-10-15

    A Monte Carlo calculation, using the MCNPX code, was carried out in order to estimate the photon and neutron spectra in two locations of two linacs operating at 15 and 18 MV. Detailed models of both linac heads were used in the calculations. Spectra were estimated below the flattening filter and at the isocenter. Neutron spectra show two components due to evaporation and knock-on neutrons. Lethargy spectra under the filter were compared to the spectra calculated from the function quoted by Tosi et al. that describes reasonably well neutron spectra beyond 1 MeV, though tends to underestimate the energy region between 10{sup -6} and 1 MeV. Neutron and Bremsstrahlung spectra show the same features regardless of the linac voltage. The amount of photons and neutrons produced by the 15 MV linac is smaller than that found for the 18 MV linac. As expected, Bremsstrahlung spectra ends according to the voltage used to accelerate the electrons. (Author)

  9. Range of Possible Beam Current in Linac4

    CERN Document Server

    Lallement, J-B; CERN. Geneva. BE Department

    2009-01-01

    Linac4 is a new accelerator under construction at CERN. It is designed to accelerate H- ions to 160MeV, for injection into the existing Proton Synchrotron Booster (PSB). It is also the front-end of the SPL Linac, a high energy proton driver that will reach the energy of 5GeV. The Linac baseline design has been done for a nominal beam peak current of 70mA but it will certainly have to deal with different currents. 132 out of 155 quadrupoles in the Linac are permanent magnets, this choice of using PMQ having fixed gradient, mainly in the DTL and in the CCDTL may then entail issues concerning the beam transverse matching and quality from current different from the nominal one. In this paper, we present the beam dynamics performances in Linac4 obtained for different currents.

  10. Measurements of longitudinal phase space in the SLC linac

    International Nuclear Information System (INIS)

    Bane, K.; Adolphsen, C.; Lavine, T.L.; Ross, M.; Seeman, J.; Thompson, K.

    1990-05-01

    In the Stanford Linear Collider the beam leaves a damping ring and then enters the Ring-to-Linac (RTL) transfer line. In the RTL it is compressed in length by a factor of 10 by means of an rf section, with which a longitudinally correlated energy variation is induced in the beam, and a following beam line which has non-zero momentum compaction. The compressed beam then enters the linac proper. In this paper we describe three measurements of longitudinal properties of the beam in the SLC linac. We present measurements of single bunch beam loading, of the energy spectrum at the end of the linac, and of the linac bunch length. Since the results of all three measurements depend on the beam's longitudinal charge distribution in the linac they, in turn, also depend on the bunch lengthening that occurs in the damping rings, as well as on the behavior of the compressor. The results of the first two measurements, in addition, depend critically on the strength of the longitudinal wakefields in the linac. The results of these three measurements are compared with simulations. For these calculations, at any given current, the potential well distortion in the damping ring is first computed. The compression process is then simulated to obtain the longitudinal charge distribution in the linac. For the first two measurements this distribution is then convolved with the calculated longitudinal wake function of the SLAC linac in order to obtain the induced voltage. Finally, the induced voltage is combined with the effect of the linac rf wave to give the final energy spectrum. 8 refs., 5 figs

  11. Production of Medical Isotopes with Electron Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Rotsch, D A; Alford, K.; Bailey, J. L.; Bowers, D. L.; Brossard, T.; Brown, M. A.; Chemerisov, S. D.; Ehst, D.; Greene, J.; Gromov, R. G.; Grudzinski, J.J.; Hafenrichter, L.; Hebden, A. S.; Henning, W.; Heltemes, T. A.; Jerden, J.; Jonah, C. D.; Kalensky, M.; Krebs, J. F.; Makarashvili, V.; Micklich, B.; Nolen, J.; Quigley, K. J.; Schneider, J. F.; Smith, N. A.; Stepinski, D. C.; Sun, Z.; Tkac, P.; Vandegrift, G. F.; Virgo, M J; Wesolowski, K. A.; Youker, A. J.

    2017-06-01

    Radioisotopes play important roles in numerous areas ranging from medical treatments to national security and basic research. Radionuclide production technology for medical applications has been pursued since the early 1900s both commercially and in nuclear science centers. Many medical isotopes are now in routine production and are used in day-to-day medical procedures. Despite these advancements, research is accelerating around the world to improve the existing production methodologies as well as to develop novel radionuclides for new medical appli-cations. Electron linear accelerators (linacs) represent a unique method for the production of radioisotopes. Even though the basic technology has been around for decades, only recently have electron linacs capable of producing photons with sufficient energy and flux for radioisotope production become available. Housed in Argonne Nation-al Laboratory’s Low Energy Accelerator Facility (LEAF) is a newly upgraded 55 MeV/25-kW electron linear ac-celerator, capable of producing a wide range of radioiso-topes. This talk will focus on the work being performed for the production of the medical isotopes 99Mo (99Mo/99mTc generator), 67Cu, and 47Sc.

  12. Linac-driven spallation-neutron source

    International Nuclear Information System (INIS)

    Jason, A.J.

    1995-01-01

    Strong interest has arisen in accelerator-driven spallation-neutron sources that surpass existing facilities (such as ISIS at Rutherford or LANSCE at Los Alamos) by more than an order of magnitude in beam power delivered to the spallation target. The approach chosen by Los Alamos (as well as the European Spallation Source) provides the full beam energy by acceleration in a linac as opposed to primary acceleration in a synchrotron or other circular device. Two modes of neutron production are visualized for the source. A short-pulse mode produces 1 MW of beam power (at 60 pps) in pulses, of length less than 1 ms, by compression of the linac macropulse through multi-turn injection in an accumulator ring. A long-pulse mode produces a similar beam power with 1-ms-long pulses directly applied to a target. This latter mode rivals the performance of existing reactor facilities to very low neutron energies. Combination with the short-pulse mode addresses virtually all applications

  13. Short wavelength FELs using the SLAC linac

    International Nuclear Information System (INIS)

    Winick, H.; Bane, K.; Boyce, R.

    1993-08-01

    Recent technological developments have opened the possibility to construct a device which we call a Linac Coherent Light Source (LCLS); a fourth generation light source, with brightness, coherence, and peak power far exceeding other sources. Operating on the principle of the free electron laser (FEL), the LCLS would extend the range of FEL operation to much aborter wavelength than the 240 mn that has so far been reached. We report the results of studies of the use of the SLAC linac to drive an LCLS at wavelengths from about 3-100 nm initially and possibly even shorter wavelengths in the future. Lasing would be achieved in a single pass of a low emittance, high peak current, high energy electron beam through a long undulator. Most present FELs use an optical cavity to build up the intensity of the light to achieve lasing action in a low gain oscillator configuration. By eliminating the optical cavity, which is difficult to make at short wavelengths, laser action can be extended to shorter wavelengths by Self-Amplified-Spontaneous-Emission (SASE), or by harmonic generation from a longer wavelength seed laser. Short wavelength, single pass lasers have been extensively studied at several laboratories and at recent workshops

  14. Superconducting linac at Inter-University Accelerator Centre: Operational challenges and solutions

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    2009-04-01

    Full Text Available A superconducting linear accelerator based on niobium quarter wave resonators has recently become operational to boost the energy of the heavy ion beams available from the existing 15 UD (unit doubled Pelletron accelerator. The niobium resonators typically performed at an accelerating field of 3–6  MV/m at 6 watts of input power in the test cryostat. When they were tested in the linac cryostat, the accelerating fields were drastically reduced and a number of other problems were also encountered. At present, all the problems have been diagnosed and solved. Many design modifications, e.g., in power coupler, mechanical tuner, helium cooling system, etc. were incorporated to solve the problems. A novel method of vibration damping was also implemented to reduce the effect of microphonics on the resonators. Finally, the accelerated beam through linac was delivered to conduct experiments.

  15. Post acceleration of a pseudospark-produced electron beam by an induction linac

    International Nuclear Information System (INIS)

    Ding, B.N.; Myers, T.J.; Rhee, M.J.

    1992-01-01

    Recently, a high-brightness electron beam produced by a simple pseudospark device has been reported. Typically, the electron beam has a peak current of up to 1 kA, FWHM pulse duration of 30 ns, and an effective emittance of 4[ 2 > r2 > - 2] 1/2 = 100 mm-mrad. The normalized brightness of the beam is estimated to be on the order of 10 11 A/(m 2 -rad 2 ). This high-brightness beam may be immediately useful for high current accelerators and free-electron lasers if the beam energy can be boosted up. In this paper, the authors present preliminary results of the post acceleration of the electron beam by using an induction linac. The pseudospark device is modified by adding a trigger electrode in the hollow cavity of the cathode so that the generation of the electron beam is synchronized with the induction linac. A simple induction linac system of 25 kV, 1 kA, 50 ns pulse is being constructed. The electron beam, which is born in a low pressure gas, will be accelerated in the same background gas. This gas provides a sufficient ion channel for necessary focusing of this high-current density beam. Preliminary results on the beam current, energy spectrum, and emittance measurements of the post-accelerated beam will be presented

  16. An Optimized Low-Charge Configuration of the LINAC Coherent Light Source

    CERN Document Server

    Emma, Paul; Huang, Zhirong; Limborg-Deprey, Cecile; Reiche, Sven; Wu, Juhao; Zolotorev, Max S

    2005-01-01

    The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser (FEL) project based on the SLAC linac. The nominal parameter set is founded on a 1-nC bunch charge and normalized emittance of about 1 micron. The most challenging issues, such as emittance generation, wakefields, and coherent synchrotron radiation (CSR), are associated with the high bunch charge. In the LCLS in particular, with its strong linac wakefields, the bunch compression process produces sharp temporal horns at the head and tail of the bunch with degraded local emittance, effectively wasting much of the charge. The sharp horns intensify CSR in the bends and further drive a strong resistive-wall wakefield in the long FEL undulator. Although these issues are not insurmountable, they suggest a lower bunch charge may be more suitable. This study uses a 0.2-nC bunch charge and 0.85-micron emittance with only 30 A of peak current in the injector, producing the same FEL saturation length. The resulting performance is more stable, has negl...

  17. Injection schemes for the TOP Linac; Schemi di iniezione per il TOP Linac

    Energy Technology Data Exchange (ETDEWEB)

    Picardi, L.; Ronsivalle, C. [ENEA, Centro Ricerche Frascati, Frascati, RM (Italy). Dipt. Innovazione; Bartolini, R. [Istituto Superiore di Sanita' , Rome (Italy)

    1999-07-01

    In this report two schemes are studied for the injection in the SCDTL section of the TOP Linac of the proton beam produced by a 7 MeV linear accelerator. The project derives by an agreement between ENEA (National Agency for New Technology, Energy and Environment) and ISS. In these new versions of the design the constraint of a synchronization of the radio frequencies of the two accelerators is suppressed. [Italian] In questo rapporto sono studiati due schemi di iniezione nella sezione accelerante SCDTL a 3 GHz del TOP (terapia oncologica con protoni) linac del fascio di protoni generato da un acceleratore lineare di 7 MeV. L'acceleratore e' frutto di una convenzione tra L'ENEA e l'Istituto Superiore di Sanita'. Rispetto a versioni precedenti del progetto, viene eliminato il vincolo della sincronizzazione delle radiofrequenze dei due acceleratori.

  18. Optimization of the beam extraction systems for the Linac4 H{sup −} ion source

    Energy Technology Data Exchange (ETDEWEB)

    Fink, D. A.; Lettry, J.; Scrivens, R.; Steyaert, D. [CERN, 1211 Geneva 23 (Switzerland); Midttun, Ø. [University of Oslo, P.O. Box 1048, 0316 Oslo (Norway); CERN, 1211 Geneva 23 (Switzerland); Valerio-Lizarraga, C. A. [Departamento de Investigación en Fisica, Universidad de Sonora, Hermosillo (Mexico); CERN, 1211 Geneva 23 (Switzerland)

    2015-04-08

    The development of the Linac 4 and its integration into CERN’s acceleration complex is part of the foreseen luminosity upgrade of the Large Hadron Collider (LHC). The goal is to inject a 160 MeV H{sup −} beam into the CERN PS Booster (PSB) in order to increase the beam brightness by a factor of 2 compared to the 50 MeV proton linac, Linac 2, that is currently in operation. The requirements for the ion source are a 45 keV H{sup −} beam of 80 mA intensity, 2 Hz repetition rate and 0.5 ms pulse length within a normalized rms-emittance of 0.25 mm· mrad. The previously installed beam extraction system has been designed for an H{sup −} ion beam intensity of 20 mA produced by an RF-volume source with an electron to H{sup −} ratio of up to 50. For the required intensity upgrades of the Linac4 ion source, a new beam extraction system is being produced and tested; it is optimized for a cesiated surface RF-source with a nominal beam current of 40 mA and an electron to H{sup −} ratio of 4. The simulations, based on the IBSIMU code, are presented. At the Brookhaven National Laboratory (BNL), a peak beam current of more than 100 mA was demonstrated with a magnetron H{sup −} source at an energy of 35 keV and a repetition rate of 2 Hz. A new extraction system is required to operate at an energy of 45 keV; simulation of a two stage extraction system dedicated to the magnetron is presented.

  19. Linac4 crosses the 100 MeV threshold

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    The new linear accelerator, which from 2020 will be the first link in the accelerator chain, has entered a new stage of its commissioning.   Members of the team in charge of the commissioning of Linac4 in the accelerator’s control room. A few hours earlier, Linac4 accelerated a beam to 107 MeV for the first time. We couldn’t have imagined a more appropriate date: on 1 July (1.07), Linac4 reached an energy of 107 MeV. Having crossed the 100 MeV barrier, the linear accelerator is now on the home straight of its commissioning. “This stage was very quick – it took less than two weeks,” says Alessandra Lombardi, deputy project leader of Linac4, in charge of the commissioning. In 2020, Linac4 will replace the existing Linac2 as the first link in the accelerator chain. It will accelerate beams of H- ions (protons surrounded by two electrons) to 160 MeV, compared to 50 MeV with Linac2. The new machine is particularly sophisticated as it comprises...

  20. First Linac4 DTL & CCDTL cavities installed in tunnel

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    On 5 June, the first Drift Tube Linac (DTL) was successfully transported to its forever home in the Linac4 tunnel. Similarly, the first Cell-Coupled Drift Tube Linac (CCDTL) was installed on 6 June. These moves marked the end of years of design and manufacturing by Linac4 teams.   Although it may seem like a relatively routine transport operation, the DTL's move was a landmark event for the entire Linac4 collaboration. "Along with the first four Cell-Coupled DTL modules, which were installed on the following two working days, these are the first accelerating structures after front-end commissioning to be installed in the tunnel," says Frank Gerigk, who is responsible for all Linac4 accelerating structures. "It is a major milestone, because work on all these structures started well over a decade ago." The transport operation was also quite a victory for the Linac4 DTL team, whose journey to a complete DTL structure has been a bit of a wild ride. &qu...

  1. Update of the Linac4-PSB Transfer Line

    CERN Document Server

    HEIN, Lutz

    2010-01-01

    The installation of Linac4 represents the first step of the upgrade plans of the CERN accelerator complex for the future in order to raise the available proton flux to attain amongst others the LHC ultimate luminosity. This linac is capable to accelerate H--ions from 45keV to 160MeV, which will be injected into the Proton Synchrotron Booster (PSB). The increase of energy from 50MeV (Linac2) to 160MeV (Linac4) allows to overcome the space charge limitations at the PSB injection, which is the main bottleneck towards higher beam brightness in the downstream accelerator chain. In order to preserve beam quality from the outlet of Linac4 to PSB injection the design of the transfer line becomes crucial. As the location of Linac4 was chosen in view of upgrade scenarios, the construction of a new transfer line is foreseen, see ref.[1] and ref.[2]. Here part of the Linac2-PSB transfer line will be re-used. In the new part of the transfer line the beam is horizontally and vertically adjusted towards the bending magnet B...

  2. Simulation studies of the LAMPF proton linac

    International Nuclear Information System (INIS)

    Garnett, R.W.; Gray, E.R.; Rybarcyk, L.J.; Wangler, T.P.

    1995-01-01

    The LAMPF accelerator consists of two 0.75-MeV injectors, one for H + and the other for H - , a separate low-energy beam transport (LEBT) line for each beam species, a 0.75 to 100-MeV drift-tube linac (DTL) operating at 201.25-MHz, a 100-MeV transition region (TR), and a 100 to 800-MeV side-coupled linac (SCL) operating at 805-MHz. Each LEBT line consists of a series of quadrupoles to transport and transversely match the beam. The LEBT also contains a prebuncher, a main buncher, and an electrostatic deflector. The deflector is used to limit the fraction of a macropulse which is seen by the beam diagnostics throughout the linac. The DTL consists of four rf tanks and uses singlet FODO transverse focusing. The focusing period is doubled in the last two tanks by placing a quadrupole only in every other drift-tube. Doublet FDO transverse focusing is used in the SCL. The TR consists of separate transport lines for the H + and H - beams. The pathlengths for the two beams differ, by introducing bends, so as to delay arrival of one beam relative to the other and thereby produce the desired macropulse time structure. Peak beam currents typically range from 12 to 18-mA for varying macropulse lengths which give an average beam current of 1-mA. The number of particles per bunch is of the order 10 8 . The work presented here is an extension of previous work. The authors have attempted to do a more complete simulation by including modeling of the LEBT. No measurements of the longitudinal structure of the beam, except phase-scans, are performed at LAMPF. The authors show that, based on simulation results, the primary causes of beam spill are inefficient longitudinal capture and the lack of longitudinal matching. Measurements to support these claims are not presently made at LAMPF. However, agreement between measurement and simulation for the transverse beam properties and transmissions serve to benchmark the simulations

  3. Development of the low energy linac systems

    International Nuclear Information System (INIS)

    Cho, Yong Sub; Kwon, H. J.; Kim, Y. H.

    2005-08-01

    The project 'Development of the Low Energy Linac System' is aiming to develop the 20 MeV proton linac system. This consists of a 50 keV proton injector, a 3 MeV RFQ, and a 20 MeV DTL. We obtained the first beam signal after the 20 MeV linac. The high power switch installed in the ion source supplies the pulsed beam into the following LEBT. The pulse operation was successfully tested. The main role of the LEBT is to match the beam into the 3 MeV RFQ. The total length of the four-vane type RFQ is about 3.26m. For the field stabilization, we used the resonant coupling scheme and dipole stabilizer rods. An 1 MW klystron supplies the RF power into the RFQ. After tuning, the field deviation of the quadrupole mode is less than 2% of the design value and the dipole fraction is less than 5% of the operating mode. The following accelerating structure is DTL which accelerate 20 mA proton beams up to 20 MeV. It consists of 4 tanks and the length of each tank is less than 5 m. The lattice is FFDD type and the integrated fields of the quadrupole magnets are 1.75 T. The inner walls of the tanks are copper-plated by PR plating method. The thickness is 100m with the roughness of 0.3m. Each drift tube consists of 6 parts and assembled by e-beam welding. The tanks and drift tubes are aligned under the installation limit of 50m by using the laser-tracker. The tuning by the slug tuners and post couplers results in the field uniformity of 2% and field sensitivity of 100%/MHz. In order to detect the beam signal, we installed the Faraday cup after the RFQ or the DTL. For the RFQ, we observed the beam of 12 A under the forward RF power of 450 kW. The beam current after DTL is about 0.5 A when RF power of 150 kW was fed into each tank

  4. The Linac4 DTL Prototype: Low and High Power Measurements

    CERN Document Server

    De Michele, G; Marques-Balula, J; Ramberger, S

    2012-01-01

    The prototype of the Linac4 Drift Tube Linac (DTL) has undergone low power measurements in order to verify the RF coupling and to adjust the post-coupler lengths based on bead-pull and spectrum measurements. Following the installation at the test stand, the cavity has been subjected to high power operation at Linac4 and SPL duty cycles. Saturation effects and multipacting have been observed and linked to X-ray emission. Voltage holding is reported in the presence of magnetic fields from permanent magnet quadrupoles (PMQ) installed in the first drift tubes.

  5. Preliminary Characterization of the O4+ Beam in Linac 3

    CERN Document Server

    Dumas, L; Scrivens, R; CERN. Geneva. AB Department

    2007-01-01

    The new GTS-LHC ECR ion source was installed in 2005. An oxygen 4+ beam was delivered to LEIR both for injection line (June 2005) and for the ring commissioning (September to December 2005). During these runs, studies were made of the beam transport in the Linac and towards LEIR. Some of the most significant results concerning the Linac are presented in this report. From 2006 the ECR source and the Linac3 delivered a lead beam for the LEIR commissioning, leaving some questions open for the oxygen beam transport. This report serves as a summary of the status of the investigations on the oxygen beam.

  6. High-Performance Beam Simulator for the LANSCE Linac

    International Nuclear Information System (INIS)

    Pang, Xiaoying; Rybarcyk, Lawrence J.; Baily, Scott A.

    2012-01-01

    A high performance multiparticle tracking simulator is currently under development at Los Alamos. The heart of the simulator is based upon the beam dynamics simulation algorithms of the PARMILA code, but implemented in C++ on Graphics Processing Unit (GPU) hardware using NVIDIA's CUDA platform. Linac operating set points are provided to the simulator via the EPICS control system so that changes of the real time linac parameters are tracked and the simulation results updated automatically. This simulator will provide valuable insight into the beam dynamics along a linac in pseudo real-time, especially where direct measurements of the beam properties do not exist. Details regarding the approach, benefits and performance are presented.

  7. Transverse Matching Progress Of The SNS Superconducting Linac

    International Nuclear Information System (INIS)

    Zhang, Yan; Cousineau, Sarah M.; Liu, Yun

    2011-01-01

    Experience using laser-wire beam profile measurement to perform transverse beam matching in the SNS superconducting linac is discussed. As the SNS beam power is ramped up to 1 MW, transverse beam matching becomes a concern to control beam loss and residual activation in the linac. In our experiments, however, beam loss is not very sensitive to the matching condition. In addition, we have encountered difficulties in performing a satisfactory transverse matching with the envelope model currently available in the XAL software framework. Offline data analysis from multi-particle tracking simulation shows that the accuracy of the current online model may not be sufficient for modeling the SC linac.

  8. A new method for improving beam quality of LINAC

    International Nuclear Information System (INIS)

    Xie Jialin; Li Fengtian; Wang Yanshan; Wang Bosi

    1999-01-01

    The principle of the self-adaptive feed-forward (SAFF) control to improve the beam quality of linac is introduced. the analytical procedure for calculating the control signals, the structure of a practical control system, and applications of SAFF in klystron, RF gun, and linac are presented, especially the application in the thermionic gun whose response is non-linear, time-variant and of large time-delay. The described control system is operational and some primary experimental results have been obtained, including the control of amplitude and phase fluctuations of the klystron output, the microwave field in the gun cavity and linac

  9. History of the JAERI linac facility for 33 years

    International Nuclear Information System (INIS)

    Ohkubo, Makio; Mizumoto, Motoharu; Nakajima, Yutaka; Mashiko, Katsuo

    1994-01-01

    The JAERI electron linear accelerator will be shutdown and disassembled at the end of 1993. At the JAERI, a prototype 20 MeV linac was constructed at 1960, and was used for the neutron time-of-flight experiments and for the isotope productions. An upgraded 120 MeV linac was constructed at 1972, and was used for many fields of research works until 1993. History of the JAERI Linac and the results of the works made using these facilities are reviewed, and also R/D on the accelerator engineering are described briefly. (author)

  10. Initial operation of the Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K. W.

    1979-01-01

    Initial operation and recent development of the Argonne superconducting heavy-ion linac are discussed. The linac has been developed in order to demonstrate a cost-effective means of extending the performance of electrostatic tandem accelerators. The results of beam acceleration tests which began in June 1978 are described. At present 7 of a planned array of 22 resonators are operating on-line, and the linac system provides an effective accelerating potential of 7.5 MV. Although some technical problems remain, the level of performance and reliability is sufficient that appreciable beam time is becoming available to users.

  11. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystronlike interaction with the accelerating cavities, leading to enhanced momentum spread. In this paper, we describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  12. Radiation processing with the Messina electron linac

    International Nuclear Information System (INIS)

    Auditore, L.; Barna, R.C.; De Pasquale, D.; Emanuele, U.; Loria, D.; Morgana, E.; Trifiro, A.; Trimarchi, M.

    2008-01-01

    In the last decades radiation processing has been more and more applied in several fields of industrial treatments and scientific research as a safe, reliable and economic technique. In order to improve existing industrial techniques and to develop new applications of this technology, at the Physics Department of Messina University a high power 5 MeV electron linac has been studied and set-up. The main features of the accelerating structure will be described together with the distinctive features of the delivered beam and several results obtained by electron beam irradiations, such as improvement of the characteristics of polymers and polymer composite materials, synthesis of new hydrogels for pharmaceutical and biomedical applications, reclaim of culture ground, sterilization of medical devices, development of new dosimeters for very high doses and dose rates required for monitoring of industrial irradiations

  13. The injector linac for the Mainz microtron

    International Nuclear Information System (INIS)

    Euteneuer, H.; Braun, H.; Herminghaus, H.; Scholer, H.; Weis, T.

    1988-01-01

    The design and setup of a 3.5 MeV, 100μA injector for a cascade of race track microtrons is presented. It replaces a 2.1 MeV Van De Graaff for getting higher reliability, improved beam dynamics in the first RTM by increased and more stable input energy, as well as an easier access and a better vacuum to launch a beam of polarized electrons. In this paper, the considerations which led under given boundary conditions to the final design concept are discussed and its realization with PARMELA is described. Details of the linac setup are given. First operation showed a good longitudinal performance (energy stability ≤ ±2 star 10 -4 , spectrum ≤ 1 star 10 -3 FWHM, bunch length ≤ ± 1.5 degrees) and an excellent reproducibility of machine operation

  14. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S. Jr.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystron-like interaction with the accelerating cavities leading to enhanced momentum spread. In this paper, the author describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  15. A new trajectory correction technique for linacs

    International Nuclear Information System (INIS)

    Raubenheimer, T.O.; Ruth, R.D.

    1990-06-01

    In this paper, we describe a new trajectory correction technique for high energy linear accelerators. Current correction techniques force the beam trajectory to follow misalignments of the Beam Position Monitors. Since the particle bunch has a finite energy spread and particles with different energies are deflected differently, this causes ''chromatic'' dilution of the transverse beam emittance. The algorithm, which we describe in this paper, reduces the chromatic error by minimizing the energy dependence of the trajectory. To test the method we compare the effectiveness of our algorithm with a standard correction technique in simulations on a design linac for a Next Linear Collider. The simulations indicate that chromatic dilution would be debilitating in a future linear collider because of the very small beam sizes required to achieve the necessary luminosity. Thus, we feel that this technique will prove essential for future linear colliders. 3 refs., 6 figs., 2 tabs

  16. Wall current monitor for SPring-8 linac

    International Nuclear Information System (INIS)

    Yanagida, Kenichi; Yamada, Kouji; Yokoyama, Minoru

    1994-06-01

    A fast rise time, broad band width and wide dynamic range wall current monitor was developed for SPring-8 linac. The performances are a rise time of ∼250ps, an effective impedance of 1.4Ω (output of ∼1.4V/A) and a bandwidth of 18kHz-2GHz. From a result of examination using 40ns electron beam, a significant change of effective impedance was not observed when a peak current was changed up to 12A or when a beam was moved by 8mm in a vacuum pipe. A circuit model that includes a core inductor loop was constructed. Using this model effective impedance and band width were calculated and compared to measured ones. They agreed very well except one part. In consequence the mechanism of wall current monitor can be explained by means of this model. (author)

  17. FRIB driver linac vacuum model and benchmarks

    CERN Document Server

    Durickovic, Bojan; Kersevan, Roberto; Machicoane, Guillaume

    2014-01-01

    The Facility for Rare Isotope Beams (FRIB) is a superconducting heavy-ion linear accelerator that is to produce rare isotopes far from stability for low energy nuclear science. In order to achieve this, its driver linac needs to achieve a very high beam current (up to 400 kW beam power), and this requirement makes vacuum levels of critical importance. Vacuum calculations have been carried out to verify that the vacuum system design meets the requirements. The modeling procedure was benchmarked by comparing models of an existing facility against measurements. In this paper, we present an overview of the methods used for FRIB vacuum calculations and simulation results for some interesting sections of the accelerator. (C) 2013 Elsevier Ltd. All rights reserved.

  18. Emittance variations in current-amplifying ion induction linacs

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1991-01-01

    Since 1985 the Heavy Ion Fusion Accelerator Research program at the Lawrence Berkeley Laboratory has been studying current amplification and emittance variations in MBE-4, a four-cesium-beam induction linac. This experiment models much of the accelerator physics of the electrostatically focused section of a fusion driver. Four space-charge dominated Cs + beams, initially about one meter in length at currents of 5-10 mA, are focused by electrostatic quadrupoles and accelerated in parallel from approximately 200 keV up to one MeV by 24 accelerating gaps. Final currents of 20-40 mA per beam are typical. Recent experiments with extremely low emittance beams (var-epsilon n =0.03 mm-mRad) have investigated variations of transverse and longitudinal normalized emittance for drifting and accelerating beams. These very strongly tune-depressed beams (σ 0 =72 degree, σ∼6 degree) are difficult to match to the accelerator so as to avoid emittance growth during acceleration. During transport strong emittance fluctuations are observed in good qualitative agreement with simulations. Warmer beams with less tune depression exhibit little to no emittance growth, show smaller emittance fluctuations, and are much easier to match. A summary of findings from the MBE-4 studies is presented

  19. Emittance variations in current-amplifying ion induction linacs

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1991-04-01

    Since 1985 the Heavy Ion Fusion Accelerator Research program at the Lawrence Berkeley Laboratory has been studying current amplification and emittance variations in MBE-4, a four-cesium-beam induction linac. This experiment models much of the accelerator physics of the electrostatically focused section of a fusion driver. Four space-charge dominated Cs + beams, initially about one meter in length at currents of 5--10 mA, are focused by electrostatic quadrupoles and accelerated in parallel from approximately 200 keV up to one MeV by 24 accelerating gaps. Final currents of 20--40 mA per beam are typical. Recent experiments with extremely low emittance beams (ε n = 0.03 mm-mRad) have investigated variations of transverse and longitudinal normalized emittance for drifting and accelerating beams. These very strongly tune-depressed beams (σ o = 72 degrees, σ∼6 degree) are difficult to match the accelerator so as to avoid emittance growth during acceleration. During transport strong emittance fluctuations are observed in good qualitative agreement with simulations. Warmer beams with less tune depression exhibit little to no emittance growth, show smaller emittance fluctuations, and are much easier to match. A summary of findings from the MBE-4 studies is presented. 12 refs., 8 figs

  20. Verification of Radiation Isocenter on Linac Beam 6 MV using Computed Radiography

    Science.gov (United States)

    Irsal, Muhammad; Hidayanto, Eko; Sutanto, Heri

    2017-06-01

    Radiation isocenter is more important part of quality assurance for the linear accelerator (Linac) due to radiation isocenter is a main location in irradiation radiotherapy, isocenter can shift when the gantry and collimator rotation. In general, the radiation isocenter verification using a special film. This research was conducted radiation isocenter verification using computed radiography with digital image processing techniques. Image acquisition was done using the modalities of Linac 6 MV with star shot method is star-shaped beam due to rotation of the collimator, gantry and couch. Then do the delineation on each beam to determine the centroid and beam diameter. By the results of verification of radiation isocenter performed on collimator and the couch, it shows that the size diameter for rotational collimator is 0.632 mm and 0.458 mm for the couch. Based on AAPM report 40 about the size of the Linac radiation isocenter diameter used in this study is still in good condition and worth to be operated because the value of the radiation isocenter diameter is below 2 mm.

  1. Verification of Radiation Isocenter on Linac Beam 6 MV using Computed Radiography

    International Nuclear Information System (INIS)

    Irsal, Muhammad; Hidayanto, Eko; Sutanto, Heri

    2017-01-01

    Radiation isocenter is more important part of quality assurance for the linear accelerator (Linac) due to radiation isocenter is a main location in irradiation radiotherapy, isocenter can shift when the gantry and collimator rotation. In general, the radiation isocenter verification using a special film. This research was conducted radiation isocenter verification using computed radiography with digital image processing techniques. Image acquisition was done using the modalities of Linac 6 MV with star shot method is star-shaped beam due to rotation of the collimator, gantry and couch. Then do the delineation on each beam to determine the centroid and beam diameter. By the results of verification of radiation isocenter performed on collimator and the couch, it shows that the size diameter for rotational collimator is 0.632 mm and 0.458 mm for the couch. Based on AAPM report 40 about the size of the Linac radiation isocenter diameter used in this study is still in good condition and worth to be operated because the value of the radiation isocenter diameter is below 2 mm. (paper)

  2. Development of an IH-type linac for the acceleration of high current heavy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Haehnel, Jan Hendrik

    2017-07-20

    The Facility for Antiproton and Ion Research (FAIR) at GSI Darmstadt will provide unprecedented intensities of protons and heavy ions up to uranium at energies of up to 29 GeV for protons and 2.7 GeV/u for U{sup 28+}. To achieve high intensities in the synchrotron accelerators, high beam currents have to be provided by the injector linear accelerators. High current heavy ion beams are provided by the Universal Linear Accelerator (UNILAC), which in its current state will not be able to provide the required FAIR beam currents. This thesis deals with the development of upgrades for the UNILAC to ensure its high current capability. The first improvement is a matching section (MEBT) for the interface between the RFQ and the IH-DTL of the existing high current injector HSI at the UNILAC. With this new MEBT section, particle losses are eliminated and the overall beam quality is improved. As a second improvement, a complete replacement of the existing Alvarez-DTL is presented. A combination of efficient IH-type cavities and KONUS beam dynamics results in a reduction of the linac length from about 60 m (Alvarez) to just 23 m (new IH-DTL) while providing the same energy and fulfilling FAIR requirements of a high beam current and beam quality. This thesis contains a detailed beam dynamics design of the new linac including some fundamental investigations of the KONUS beam dynamics concept. A cross-check of the beam dynamics design was performed with two independent multi-particle simulation codes. Detailed error studies were conducted to investigate the influence of manufacturing, alignment and operating errors on the beam dynamics performance. Additionally, all five linac cavities were designed, optimized, and their RF parameters including power requirements calculated to provide a comprehensive linac design.

  3. Development of an IH-type linac for the acceleration of high current heavy ion beams

    International Nuclear Information System (INIS)

    Haehnel, Jan Hendrik

    2017-01-01

    The Facility for Antiproton and Ion Research (FAIR) at GSI Darmstadt will provide unprecedented intensities of protons and heavy ions up to uranium at energies of up to 29 GeV for protons and 2.7 GeV/u for U 28+ . To achieve high intensities in the synchrotron accelerators, high beam currents have to be provided by the injector linear accelerators. High current heavy ion beams are provided by the Universal Linear Accelerator (UNILAC), which in its current state will not be able to provide the required FAIR beam currents. This thesis deals with the development of upgrades for the UNILAC to ensure its high current capability. The first improvement is a matching section (MEBT) for the interface between the RFQ and the IH-DTL of the existing high current injector HSI at the UNILAC. With this new MEBT section, particle losses are eliminated and the overall beam quality is improved. As a second improvement, a complete replacement of the existing Alvarez-DTL is presented. A combination of efficient IH-type cavities and KONUS beam dynamics results in a reduction of the linac length from about 60 m (Alvarez) to just 23 m (new IH-DTL) while providing the same energy and fulfilling FAIR requirements of a high beam current and beam quality. This thesis contains a detailed beam dynamics design of the new linac including some fundamental investigations of the KONUS beam dynamics concept. A cross-check of the beam dynamics design was performed with two independent multi-particle simulation codes. Detailed error studies were conducted to investigate the influence of manufacturing, alignment and operating errors on the beam dynamics performance. Additionally, all five linac cavities were designed, optimized, and their RF parameters including power requirements calculated to provide a comprehensive linac design.

  4. A heavy ion linac complex for RI beams

    International Nuclear Information System (INIS)

    Arai, Shigeaki

    1995-01-01

    A heavy ion linac complex for RI-beams has been under construction since fiscal year 1992 at INS. The linac complex comprises following accelerating structures: a 25.5-MHz split coaxial RFQ (SCRFQ), a 51-MHz interdigital-H (IH) linac, and a 25.5-MHz rebuncher cavity. The SCRFQ with modulated vanes accelerates ions with a charge-to-mass ratio (q/A) greater than 1/30 from 2 to 170 keV/u. The IH linac comprises four cavities and three magnetic quadrupole triplets placed between cavities, accelerates ions with q/A≥1/10, and varies the output energy continuously in the range 0.17 ∼1.05 MeV/u. The rebuncher cavity with six accelerating gaps is a double coaxial λ/4 resonator, and the total accelerating voltage is 200 kV. (author)

  5. HOM Dampers or not in Superconducting RF Proton Linacs

    CERN Document Server

    Tückmantel, Joachim

    2009-01-01

    Circular machines are plagued by Coupled Bunch Instabilities, driven by impedance peaks, irrespectively of their frequency relation to machine lines; hence all cavity Higher Order Modes are possible drivers. This is the fundamental reason that all superconducting RF cavities in circular machines are equipped with HOM dampers. This raises the question if HOM damping would not be imperative also in high current proton linacs where a mechanism akin to CBI might exist. To clarify this question we have simulated the longitudinal bunched beam dynamics in linacs, allowing bunch-to-bunch variations in time-of-arrival. Simulations were executed for a generic proton linac with properties close to SNS or the planned SPL at CERN. It was found that for monopole HOMs with high Qext large beam scatter or even beam loss cannot be excluded. Therefore omitting HOM dampers on superconducting RF cavities in high current proton linacs, even pulsed ones, is a very risky decision.

  6. HOM Dampers or not in SUPERCONDUCTING RF Proton Linacs

    CERN Document Server

    Tückmantel, Joachim

    2009-01-01

    Circular machines are plagued by Coupled Bunch Instabilities, driven by impedance peaks, irrespectively of their frequency relation to machine lines; hence all cavity Higher Order Modes are possible drivers. This is the fundamental reason that all superconducting RF cavities in circular machines are equipped with HOM dampers. This raises the question if HOM damping would not be imperative also in high current proton linacs where a mechanism akin to CBI might exist. To clarify this question we have simulated the longitudinal bunched beam dynamics in linacs, allowing bunch-to-bunch variations in time-of-arrival. Simulations were executed for a generic proton linac with properties close to SNS or the planned SPL at CERN. It was found that for monopole HOMs with high Qext large beam scatter or even beam loss cannot be excluded. Therefore omitting HOM dampers on superconducting RF cavities in high current proton linacs, even pulsed ones, is a very risky decision.

  7. RF linac designs with beams in thermal equilibrium

    International Nuclear Information System (INIS)

    Reiser, M.; Brown, N.

    1996-01-01

    Beams in conventional radio-frequency linear accelerators (rf linacs) usually have a transverse temperature which is much larger than the longitudinal temperature. With high currents, space charge forces couple the transverse and longitudinal particle motions, driving the beam toward thermal equilibrium, which leads to emittance growth and halo formation. A design strategy is proposed in which the beam has equal transverse and longitudinal temperatures through the entire linac, avoiding these undesirable effects. For such equipartitioned linac beams, simple analytical relationships can be derived for the bunch size, tune depression, and other parameters as a function of beam intensity, emittance, and external focusing. These relations were used to develop three conceptual designs for a 938 MeV, 100 mA proton linac with different tune depressions, which are presented in this paper. copyright 1996 American Institute of Physics

  8. Reduction of losses in linacs for protons or heavy ions

    International Nuclear Information System (INIS)

    Claus, J.

    1977-01-01

    It is necessary to minimize the beam losses in linacs for high average currents in order to avoid serious problems due to radiation damage, dissipation and radio activation of the accelerator structure. A large part of the losses in existing linacs is due to incomplete bunching of the injected beam. Proposed improvements generally appear to be deficient in one or more respects if applied to linacs with conventional frequencies, injection energies and current densities. By preceding the linac proper with an accelerating structure and an energy analyzer, it becomes possible to separate the particles that remained outside the buckets from those that are inside so that they can be dumped in a controlled manner

  9. Overview of High Intensity Linac Programs in Europe

    CERN Document Server

    Garoby, R

    2004-01-01

    Recent years have seen a boost in the support by the European Union (EU) of accelerator research in Europe. Provided they coordinate their efforts and define common goals and strategies, laboratories and institutions from the member states can receive a financial support reaching 50% of the total project cost. In the field of High Intensity Linacs, the EU has already supported the EURISOL initiative for nuclear physics, which this year is applying for funding of a Design Study, and the development of linacs for Waste Transmutation. More recently, an initiative for high-energy physics has been approved, which includes a programme for the development of pulsed linac technologies. The coordination and synergy imposed by the EU rules increase the benefit of the allocated resources. Combined with the ongoing internal projects in the partner laboratories, these European initiatives represent a strong effort focussed towards the development of linac technologies. This paper summarises the requests from the various E...

  10. Post-accelerator LINAC design for the VECC RIB project

    Indian Academy of Sciences (India)

    acclerator type of RIB facility. The scheme utilises the existing = 130 room temperature variable energy cyclotron machine as the primary accelerator for the production of RIBs and radio frequency quadrupole (RFQ) and LINAC modules for ...

  11. An induction Linac driven heavy-ion fusion systems model

    International Nuclear Information System (INIS)

    Zuckerman, D.S.; Driemeyer, D.E.; Waganer, L.M.; Dudziak, D.J.

    1988-01-01

    A computerized systems model of a heavy-ion fusion (HIF) reactor power plant is presented. The model can be used to analyze the behavior and projected costs of a commercial power plant using an induction linear accelerator (Linac) as a driver. Each major component of the model (targets, reactor cavity, Linac, beam transport, power flow, balance of plant, and costing) is discussed. Various target, reactor cavity, Linac, and beam transport schemes are examined and compared. The preferred operating regime for such a power plant is also examined. The results show that HIF power plants can compete with other advanced energy concepts at the 1000-MW (electric) power level [cost of electricity (COE) -- 50 mill/kW . h] provided that the cost savings predicted for Linacs using higher charge-state ions (+3) can be realized

  12. Finite element thermal study of the Linac4 plasma generator

    International Nuclear Information System (INIS)

    Faircloth, D.; Kronberger, M.; Kuechler, D.; Lettry, J.; Scrivens, R.

    2010-01-01

    The temperature distribution and heat flow at equilibrium of the plasma generator of the rf-powered noncesiated Linac4 H - ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW rf power, 2 Hz repetition rate, and 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of the Superconducting Proton Linac (SPL), an extrapolation of the heat load toward 100 kW rf power, 50 Hz repetition rate, and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in the high-power mode of SPL.

  13. Finite element thermal study of the Linac4 plasma generator

    Energy Technology Data Exchange (ETDEWEB)

    Faircloth, D. [STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom); Kronberger, M.; Kuechler, D.; Lettry, J.; Scrivens, R. [BE-ABP, Hadron Sources and Linacs, CERN, CH-1211 Geneva (Switzerland)

    2010-02-15

    The temperature distribution and heat flow at equilibrium of the plasma generator of the rf-powered noncesiated Linac4 H{sup -} ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW rf power, 2 Hz repetition rate, and 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of the Superconducting Proton Linac (SPL), an extrapolation of the heat load toward 100 kW rf power, 50 Hz repetition rate, and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in the high-power mode of SPL.

  14. Present status of the TOHOKU 300 MeV linac

    International Nuclear Information System (INIS)

    Takahashi, Shigenobu; Oyamada, Masayuki; Urasawa, Shigekazu; Nakazato, Toshiharu; Kurihara, Akira; Mutoh, Masakatu; Shibasaki, Yoshinobu; Oonuma, Tadahiro

    1993-01-01

    The TOHOKU linac that was constructed about a quarter century before has been operated without serious trouble recently. This report describes as follows: main trouble, maintenance, present performance of the machine and status of operation. (author)

  15. A high current electron gun for the IEAv linac

    International Nuclear Information System (INIS)

    Muraro, A. Jr.; Stopa, C.R.S.; Romao, B.M.V.; Jorge, A.M.; Takahashi, J.

    2001-01-01

    This work presents the design, construction and characterization of a new electron gun for the linear electron accelerator (linac) which is under construction at the Instituto de Estudos Avancados (IEAv)

  16. 1-GeV Linac Upgrade Study at Fermilab

    International Nuclear Information System (INIS)

    Popovic, M.; Moretti, A.; Noble, R.; Schmidt, C.W.

    1998-09-01

    A linac injector for a new proton source complex at Fermilab is assumed to have a kinetic energy of 1 GeV. This linac would be sized to accelerate 100 mA of H - beam in a 200 microsecond pulse at a 15 Hz repetition rate. This would be adequate to produce ∼10 14 protons per pulse allowing for future improvements of the new proton source complex. An alternate proposal is to add 600 MeV of side coupled cavity linac at 805 MHz to the existing 400 MeV Linac. This addition may either be in a new location or use the present Booster tunnel. A discussion of these possibilities will be given

  17. CAS CERN Accelerator School: Cyclotrons, linacs and their applications. Proceedings

    International Nuclear Information System (INIS)

    Turner, S.

    1996-01-01

    These proceedings present the lectures given at the eighth specialized course organized by the CERN Accelerator School (CAS), the topic this time being 'Cyclotrons, Linacs and Their Applications'. Following an introductory lecture on linacs, the fundamental features of electron, ion and induction linacs are described together with their RF systems and particle sources. Cyclotrons are then introduced followed by details of their different types, their magnet and RF design, and their injection and extraction systems, with a glance towards exotic and possible future machines. Chapters are then presented on the use of linacs and cyclotrons for medical, fission, fusion and material applications, as well as for isotope production. Finally, descriptions of the design of a radioisotope facility, the matching of accelerators to their task and the computational tools used in their design are included. (orig.)

  18. CAS CERN Accelerator School: Cyclotrons, linacs and their applications. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Turner, S [ed.

    1996-03-04

    These proceedings present the lectures given at the eighth specialized course organized by the CERN Accelerator School (CAS), the topic this time being `Cyclotrons, Linacs and Their Applications`. Following an introductory lecture on linacs, the fundamental features of electron, ion and induction linacs are described together with their RF systems and particle sources. Cyclotrons are then introduced followed by details of their different types, their magnet and RF design, and their injection and extraction systems, with a glance towards exotic and possible future machines. Chapters are then presented on the use of linacs and cyclotrons for medical, fission, fusion and material applications, as well as for isotope production. Finally, descriptions of the design of a radioisotope facility, the matching of accelerators to their task and the computational tools used in their design are included. (orig.).

  19. Fast automatic system for measurements of beam parameters of the MMF linac

    International Nuclear Information System (INIS)

    Reinhardt-Nickulin, P.; Bragin, S.; Ilinsky, N.; Senichev, Yu.

    1992-01-01

    Fast transverse beam profile and current monitoring systems have been tested at the Linear Accelerator of Moscow Meson Factory. The signals for each system are derived from multiwire secondary emission chamber and beam current transformer. Each beam pulse is digitized by fast ADC's. There are two modes for systems. First one is for detailed beam adjustment and second one is for normal 100 Hz rate of the MMF Linac. Essential features of the hardware, software, data acquisition, measurement accuracy and beam results are presented. (author)

  20. Linac 1 in the process of being pulled back

    CERN Multimedia

    Photographic Service; CERN PhotoLab

    1985-01-01

    As injector to the PS Booster, Linac 1 was replaced by Linac 2 in 1980. It continued to be used for the acceleration of oxygen and sulfur ions and, from 1981 to 1996, of protons and negative hydrogen ions for LEAR. In 1984, its Cockcroft-Walton preinjector was replaced by a much smaller RFQ, which allowed it to be moved to a more convenient location.

  1. Effect of cooling water on stability of NLC linac components

    Energy Technology Data Exchange (ETDEWEB)

    F. Le Pimpec et al.

    2003-02-11

    Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

  2. Effect of Cooling Water on Stability of NLC Linac Components

    Energy Technology Data Exchange (ETDEWEB)

    Le Pimpec, Frederic

    2002-11-01

    Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structures and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. A design, incorporating the proper decoupling of structure vibrations from the linac quadrupoles, is being pursued.

  3. Nonlinear space charge effect of bunched beam in linac

    International Nuclear Information System (INIS)

    Chen Yinbao

    1992-02-01

    The nonlinear space charge effect due to the nonuniform particle density distribution in bunched beam of a linac is discussed. The formulae of nonlinear space charge effect and nonlinear focusing forces were derived for the bunched beam with Kapchinskij-Vladimirskij (K-V) distribution, waterbag (WB) distribution, parabolic (PA) distribution, and Gauss (GA) distribution in both of the space charge disk model and space charge cylinder model in the waveguide of a linac

  4. Evolution of the 400 MeV linac design

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1987-01-01

    The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also

  5. Vibrational Stability of NLC Linac and Final Focus Components

    Energy Technology Data Exchange (ETDEWEB)

    Le Pimpec, Frederic

    2002-09-25

    Vertical vibration of linac components (accelerating structures, girders and quadrupoles) in the NLC has been studied experimentally and analytically. Effects such as structural resonances and vibration caused by cooling water both in accelerating structure and quadrupoles have been considered. Experimental data has been compared with analytical predictions and simulations using ANSYS. Design to properly decouple the structure vibrations from the linac quadrupoles is being pursued.

  6. Induction linac driven relativistic klystron and cyclotron autoresonance maser experiments

    International Nuclear Information System (INIS)

    Goodman, D.L.; Birx, D.L.; Danly, B.G.

    1991-01-01

    In this paper design and experimental results are presented from two high power microwave generation experiments utilizing a high repetition rate induction linac generated electron beam. A relativistic klystron has generated more than 100 MW microwave pulses in X-band for 50 ns without pulse shortening or breakdown. design studies for the first cyclotron autoresonance maser (CARM) amplifier using an induction linac electron beam are also presented

  7. Evolution of the 400 MeV linac design

    Energy Technology Data Exchange (ETDEWEB)

    MacLachlan, J.A.

    1987-11-09

    The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also.

  8. LINAC4, A New $H^{-}$ Linear Injector at CERN

    CERN Document Server

    Garoby, R; Hanke, K; Lombardi, A M; Rossi, C; Vretenar, M

    2004-01-01

    Linac2, the present injector of the CERN PS Booster, limits the performance of the proton accelerator complex because of its low output energy (50 MeV). To remove this bottleneck, a higher energy linac is proposed (called â€ワLinac4†) which will double the brightness and the intensity of the beam delivered by the PSB and ensure the â€ワultimate” beam is available for LHC. Linac4 will deliver H- ions at a kinetic energy of 160 MeV. It is designed to be usable as the front-end of a future multi-GeV multi-MW linear accelerator, the â€ワSuperconducting Proton Linac” (SPL). R&D for Linac4 is now actively taking place with the support of the European Union through the Joint Research Activity HIPPI (â€ワHigh Intensity Pulsed Proton Injectors”), and of three ISTC projects involving three major Russian laboratories (BINP, IHEP and ITEP) and two nuclear centres (VNIIEF and VNIITF). The design of this new accelerator and the on-going developments are described.

  9. Design and Development of RF Structures for Linac4

    CERN Document Server

    Vretenar, M; Gerigk, F; Pasini, M; Wegner, R

    2006-01-01

    Linac4 is a new 160 MeV H− linac proposed at CERN to replace the 50 MeV Linac2 as injector to the PS Booster, with the goal of doubling its brightness and intensity. The present design foresees after RFQ and chopping line a sequence of three accelerating structures: a Drift Tube Linac (DTL) from 3 to 40 MeV, a Cell-Coupled DTL (CCDTL) to 90 MeV and a Side Coupled Linac (SCL) up to the final energy. The DTL and CCDTL operate at 352 MHz, while in the SCL the frequency is doubled to 704 MHz. Although the injection in the PS Booster requires only a low duty cycle, the accelerating structures are designed to operate at the high duty cycle required by a possible future extension to a high-power linac driver for a neutrino facility. This paper presents the different accelerating structures, underlining the progress in the design of critical resonator elements, like post-couplers in the DTL, coupling slots in the CCDTL and bridge couplers for the SCL. Prototyping progress for the different structures is reported...

  10. Linac design for intense hadron beams

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chuan

    2009-12-14

    Based on the RFQ and H-type DTL structures, this dissertation is dedicated to study the beam dynamics in the presence of significantly strong space-charge effects while accelerating intense hadron beams in the low- and medium-{beta} region. Besides the 5 mA/30 mA, 17 MeV proton injector (RFQ+DTL) and the 125 mA, 40 MeV deuteron DTL of the EUROTRANS and IFMIF facilities, a 200 mA, 700 keV proton RFQ has been also intensively studied for a small-scale but ultra-intense neutron source FRANZ planned at Frankfurt University. The most remarkable properties of the FRANZ RFQ and the IFMIF DTL are the design beam intensities, 200 mA and 125 mA. A new design approach, which can provide a balanced and accelerated beam bunching at low energy, has been developed for intense beams. To design the IFMIF DTL and the injector DTL part of the EUROTRANS driver linac, which have been foreseen as the first real applications of the novel superconducting CH-DTL structure, intensive attempts have been made to fulfill the design goals under the new conditions. For the IFMIF DTL, the preliminary IAP design has been considerably improved with respect to the linac layout as well as the beam dynamics. By reserving sufficient drift spaces for the cryosystem, diagnostic devices, tuner and steerer, introducing SC solenoid lenses and adjusting the accelerating gradients and accordingly other configurations of the cavities, a more realistic, reliable and efficient linac system has been designed. On the other hand, the specifications and positions of the transverse focusing elements as well as the phase- and energy-differences between the bunch-center particle and the synchronous particle at the beginning of the {phi}{sub s}=0 sections have been totally redesigned. For the EUROTRANS injector DTL, in addition to the above-mentioned procedures, extra optimization concepts to coordinate the beam dynamics between two intensities have been applied. In the beam transport simulations for both DTL designs

  11. Linac design for intense hadron beams

    International Nuclear Information System (INIS)

    Zhang, Chuan

    2009-01-01

    Based on the RFQ and H-type DTL structures, this dissertation is dedicated to study the beam dynamics in the presence of significantly strong space-charge effects while accelerating intense hadron beams in the low- and medium-β region. Besides the 5 mA/30 mA, 17 MeV proton injector (RFQ+DTL) and the 125 mA, 40 MeV deuteron DTL of the EUROTRANS and IFMIF facilities, a 200 mA, 700 keV proton RFQ has been also intensively studied for a small-scale but ultra-intense neutron source FRANZ planned at Frankfurt University. The most remarkable properties of the FRANZ RFQ and the IFMIF DTL are the design beam intensities, 200 mA and 125 mA. A new design approach, which can provide a balanced and accelerated beam bunching at low energy, has been developed for intense beams. To design the IFMIF DTL and the injector DTL part of the EUROTRANS driver linac, which have been foreseen as the first real applications of the novel superconducting CH-DTL structure, intensive attempts have been made to fulfill the design goals under the new conditions. For the IFMIF DTL, the preliminary IAP design has been considerably improved with respect to the linac layout as well as the beam dynamics. By reserving sufficient drift spaces for the cryosystem, diagnostic devices, tuner and steerer, introducing SC solenoid lenses and adjusting the accelerating gradients and accordingly other configurations of the cavities, a more realistic, reliable and efficient linac system has been designed. On the other hand, the specifications and positions of the transverse focusing elements as well as the phase- and energy-differences between the bunch-center particle and the synchronous particle at the beginning of the φ s =0 sections have been totally redesigned. For the EUROTRANS injector DTL, in addition to the above-mentioned procedures, extra optimization concepts to coordinate the beam dynamics between two intensities have been applied. In the beam transport simulations for both DTL designs, no beam

  12. A novel electron gun for inline MRI-linac configurations

    International Nuclear Information System (INIS)

    Constantin, Dragoş E.; Fahrig, Rebecca; Holloway, Lois; Keall, Paul J.

    2014-01-01

    Purpose: This work introduces a new electron gun geometry capable of robust functioning in the presence of a high strength external magnetic field for axisymmetric magnetic resonance imaging (MRI)-linac configurations. This allows an inline MRI-linac to operate without the need to isolate the linear accelerator (linac) using a magnetic shield. This MRI-linac integration approach not only leaves the magnet homogeneity unchanged but also provides the linac flexibility to move along the magnet axis of symmetry if the source to target distance needs to be adjusted. Methods: Simple electron gun geometry modifications of a Varian 600C electron gun are considered and solved in the presence of an external magnetic field in order to determine a set of design principles for the new geometry. Based on these results, a new gun geometry is proposed and optimized in the fringe field of a 0.5 T open bore MRI magnet (GE Signa SP). A computer model for the 6 MeV Varian 600C linac is used to determine the capture efficiency of the new electron gun-linac system in the presence of the fringe field of the same MRI scanner. The behavior of the new electron gun plus the linac system is also studied in the fringe fields of two other magnets, a 1.0 T prototype open bore magnet and a 1.5 T GE Conquest scanner. Results: Simple geometrical modifications of the original electron gun geometry do not provide feasible solutions. However, these tests show that a smaller transverse cathode diameter with a flat surface and a slightly larger anode diameter could alleviate the current loss due to beam interactions with the anode in the presence of magnetic fields. Based on these findings, an initial geometry resembling a parallel plate capacitor with a hole in the anode is proposed. The optimization procedure finds a cathode-anode distance of 5 mm, a focusing electrode angle of 5°, and an anode drift tube length of 17.1 mm. Also, the linac can be displaced with ±15 cm along the axis of the 0.5 T

  13. SU-E-T-429: Feasibility Study On Three-Dimensional GRID Therapy in Conventional Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Y; Meyer, J; Timmerman, R; Hrycushko, B; Chen, B; Saha, D; Jiang, S [UT Southwestern Medical Center, Dallas, TX (United States)

    2015-06-15

    Purpose: Two-dimensional GRID therapy, traditionally planned and delivered using a dedicated GRID block or MLC modulation, has shown clinical efficacy in treating bulky tumors. However, the large dose to normal tissues outside target can be limiting. We hypothesize that modulation in the third dimension will improve dose sparing of normal tissues, maximize the bystander effect within the target, and ultimately improve the therapy effectiveness. This study aims to investigate the feasibility of a three-dimensional GRID technique using conventional LINACs to achieve a 3D lattice of high dose volumes within a target. Methods: Datasets of patient’s having large tumor sizes were used to investigate the planning and delivering of 3D GRID using a Varian TrueBeam linac. Original patient contours of PTV are exported from a TPS to DICOManTX where 3D GRID targets are generated in programmable configurations. A structure of avoidance (SOA), i.e., PTV minus GRID targets, is also generated to facilitate inverse planning to achieve the desired pattern. The artificial structures were sent back to the TPS where an IMRT or VMAT plan is designed to deliver a desired high dose to GRID targets while minimizing the dose to the SOA as much as possible. Results: The programmable GRID target generator enables us to modify the target geometry to maximize the peak-to-valley ratio. Preliminary results show that plans based on spherical GRID targets achieve a higher peak-to-valley dose ratio compared with cylindrical targets. High dose spillage outside the target was eliminated. IMRT planning requires the number of beams to be larger than 16, while for VMAT the number of arcs should be at least 4 in order to achieve dosimetric goals. Conclusion: Planning and delivering 3D GRID therapy using conventional LINACs was shown to be feasible. More research and development are required before this new modality can be implemented clinically.

  14. An Alignment of J-PARC Linac

    CERN Document Server

    Morishita, Takatoshi; Hasegawa, Kazuo; Ikegami, Masanori; Ito, Takashi; Kubota, Chikashi; Naito, Fujio; Takasaki, Eiichi; Tanaka, Hirokazu; Ueno, Akira; Yoshino, Kazuo

    2005-01-01

    J-PARC linear accelerator components are now being installed in the accelerator tunnel, whose total length is more than 400 m including the beam transport line to RCS (Rapid Cycling Synchrotron). A precise alignment of accelerator components is essential for a high quality beam acceleration. In this paper, planned alignment schemes for the installation of linac components, the fine alignment before beam acceleration, and watching the long term motion of the building are described. Guide points are placed on the floor, which acts as a reference for the initial alignment at the installation and also as a relay point for the long surveying network linking at the fine alignment. For a straight line alignment, the wire position sensor is placed on the offset position with respect to the beam center by a target holder, then a single wire can cover the accelerator cavities and the focusing magnets at the DTL-SDTL section (120m). The hydrostatic levering system (HLS) is used for watching the floor elevation (changes)...

  15. Industrial RF Linac Experiences and Laboratory Interactions

    CERN Document Server

    Peiniger, M

    2004-01-01

    Since more than two decades ACCEL Instruments GmbH at Bergisch Gladbach (formerly Siemens/Interatom) is supplying the worldwide accelerator labs with key components like rf cavities and power couplers, s.c. magnets, insertion devices, vacuum chambers and x-ray beamline equipment. Starting with the design and production of turn key SRF accelerating modules in the late 80th, meanwhile ACCEL is engineering, manufacturing, on site commissioning and servicing complete accelerators with guaranteed beam performance. Today, with a staff of more than 100 physicists and engineers and about the same number of manufacturing specialists in our dedicated production facilities, ACCEL's know how and sales volume in this field has accumulated to more than 2000 man years and several hundred Mio €, respectively. Basis of our steady development is a cooperative partnership with the world leading research labs in the respective fields. As an example, for the supply of a turn key 100 MeV injector linac for the Swiss Ligh...

  16. Failure analysis of medical Linac (LMR-15)

    International Nuclear Information System (INIS)

    Kato, Kiyotaka; Nakamura, Katsumi; Ogihara, Kiyoshi; Takahashi, Katsuhiko; Sato, Kazuhisa.

    1994-01-01

    In August 1978, Linac (LMR-15, Z4 Toshiba) was installed at our hospital and in use for 12 years up to September 1990. Recently, we completed working and failure records on this apparatus during the 12-year period, for the purpose of their analysis in the basis of reliability engineering. The results revealed operation rate of 97.85% on the average, mean time between failures (MTBF) from 40-70 hours about the beginning of its working to 280 hours for 2 years before renewal and practically satisfactory values of mean life of parts of life such as magnetron, thyratron and electron gun; the above respective values proved to be above those reported by other literature. On the other hand, we classified, by occurring system, the contents of failures in the apparatus and determined the number of failures and the temperature and humidities in case of failures to examine the correlation between the working environment and failure. The results indicated a change in humidity to gain control of failures in the dosimetric system, especially the monitoring chamber and we could back up the strength of the above correlation from a coefficient of correlation value of 0.84. (author)

  17. Induction linac drivers: Prospects for the future

    International Nuclear Information System (INIS)

    Keefe, D.

    1989-01-01

    This review is intended to place in perspective our current view of the parameter ranges for induction linac drivers that lead to attractive scenarios for civilian electrical power plants; there is a surprising degree of choice (a factor of 2 or so in most parameters) before any significant impact on the cost of energy results. The progress and goals of the US heavy-ion fusion accelerator research (HIFAR) program are reviewed. The step between the realization of the HIFAR goals and a full-scale driver is seen to be very large indeed and will require one or more significant intermediate steps which can be justified only by a commitment to advance the HIF method towards a true fusion goal. Historial anomalies in the way that fusion programs for both military and civilian applications are administered will need to be resolved; the absence of any presently perceived energy crisis results in little current sense of urgency to develop vigorous long-term energy solutions. (orig.)

  18. A cw 4-rod RFQ linac

    International Nuclear Information System (INIS)

    Fujisawa, Hiroshi

    1994-01-01

    A cw 4-rod RFQ linac system has been designed, constructed, and tested as an accelerator section of a MeV-class ion implanter system. The tank diameter is only 60 cm for 34 MHz operating frequency. An equally spaced arrangement of the RFQ electrode supporting plates is proved to be suitable for a low resonant frequency 4-rod RFQ structure. The RFQ electrode cross section is not circular but rectangular to make the handling and maintenance of the electrodes easier. The machining of the electrode is done three dimensionally. Second order corrections in the analyzing magnet of the LEBT (Low Energy Beam Transport) section assure a better transmission through and the matching to the RFQ. A new approach is introduced to measure the rf characteristics of the 4-rod RFQ. This method requires only a few capacitors and a network analyzer. Both the rf and thermal stability of the 4-rod RFQ are tested up to cw 50 kW. Beam experiments with several ions confirm the acceleration of beams to the goal energy of 83 keV/u. The ion beam intensities obtained at the RFQ output for He + , N 2+ , and C + are 32, 13, and 220 pμA, respectively. The measured beam transmissions of >80% agree with the PARMTEQ calculations. The ion implantation method also gives definitive information on the energies of an RFQ output beam. ((orig.))

  19. Delta undulator for Cornell energy recovery linac

    Directory of Open Access Journals (Sweden)

    Alexander B. Temnykh

    2008-12-01

    Full Text Available In anticipation of a new era of synchrotron radiation sources based on energy recovery linac techniques, we designed, built, and tested a short undulator magnet prototype whose features make optimum use of the unique conditions expected in these facilities. The prototype has pure permanent magnet (PPM structure with 24 mm period, 5 mm diameter round gap, and is 30 cm long. In comparison with conventional undulator magnets it has the following: (i full x-ray polarization control.—It may generate varying linear polarized as well as left and right circular polarized x rays with photon flux much higher than existing Apple-II–type devices. (ii 40% stronger magnetic field in linear and approximately 2 times stronger in circular polarization modes. This advantage translates into higher x-ray flux. (iii Compactness.—The prototype can be enclosed in a ∼20  cm diameter cylindrical vacuum vessel. These advantages were achieved through a number of unconventional approaches. Among them is control of the magnetic field strength via longitudinal motion of the magnet arrays. The moving mechanism is also used for x-ray polarization control. The compactness is achieved using a recently developed permanent magnet soldering technique for fastening PM blocks. We call this device a “Delta” undulator after the shape of its PM blocks. The presented article describes the design study, various aspects of the construction, and presents some test results.

  20. Linac4 chopper line commissioning strategy

    CERN Document Server

    Bellodi, G; Lombardi, A M; Posocco, P A; Sargsyan, E

    2010-01-01

    The report outlines the strategy for beam-based commissioning of the Linac4 3 MeV chopper line as currently scheduled to start in the second half of 2011 in the Test Stand Area. A dedicated temporary diagnostics test bench will complement the measurement devices foreseen for permanent installation in the chopper line. A commissioning procedure is set out as a series of consecutive phases, each one supposed to meet a well- defined milestone in the path to fully characterise the beam-line. Specific set-ups for each stage are defined in terms of beam characteristics, machine settings and diagnostics used. Operational guidelines are given and expected results at the relative points of measurements are shown for simulated scenarios (on the basis of multi-particle tracking studies carried out with the codes PATH and TRACEWin). These are then interpreted in the light of the resolution limits of the available diagnostics instruments to assess the precision reach on individual measurements and the feasibility of techn...

  1. Induction linac drivers: Prospects for the future

    International Nuclear Information System (INIS)

    Keefe, D.

    1988-06-01

    This review is intended to place in perspective our current view of the parameter ranges for induction linac drivers that lead to attractive scenarios for civilian electrical power plants; there is a surprising degree of choice (a factor of two or so in most parameters) before any significant impact on the cost of energy results. The progress and goals of the US Heavy Ion Accelerator Research (HIFAR) program are reviewed. The step between the realization of the HIFAR goals and a full-scale driver is seen to be very large indeed and will require one or more significant intermediate steps which can be justified only by a commitment to advance the HIF method towards a true fusion goal. Historical anomalies in the way that fusion programs for both military and civilian applications are administered will need to be resolved; the absence of any presently perceived energy crisis results in little current sense of urgency to develop vigorous long-term energy solutions. 12 refs., 3 figs., 1 tab

  2. Status of the SNS Linac An Overview

    CERN Document Server

    Holtkamp, N

    2004-01-01

    The Spallation Neutron Source SNS is a second generation pulsed neutron source and under construction at Oak Ridge National Laboratory. The SNS is funded by the U.S. Department of Energy?s Office of Basic energy Sciences and is dedicated to the study of the structure and dynamics of materials by neutron scattering. A collaboration composed of six national laboratories (ANL, BNL, TJNAF, LANL, LBNL, ORNL) is responsible for the design and construction of the various subsystems. With the official start in October 1998, the operation of the facility will begin in 2006 and deliver a 1.0 GeV, 1.4 MW proton beam with a pulse length of approximately 700 nanoseconds on a liquid mercury target. The multi-lab collaboration allowed access to a large variety of expertise in order to enhance the delivered beam power by almost an order of magnitude compared to existing neutron facilities. The SNS linac consists of a combination of room temperature and superconducting structures and will be the first pulsed high power sc lin...

  3. Wakefield Band Partitioning in LINAC Structures

    International Nuclear Information System (INIS)

    Jones, Roger M

    2003-01-01

    In the NLC project multiple bunches of electrons and positrons will be accelerated initially to a centre of mass of 500 GeV and later to 1 TeV or more. In the process of accelerating 192 bunches within a pulse train, wakefields are excited which kick the trailing bunches off axis and can cause luminosity dilution and BBU (Beam Break Up). Several structures to damp the wakefield have been designed and tested at SLAC and KEK and these have been found to successfully damp the wakefield [1]. However, these 2π/3 structures suffered from electrical breakdown and this has prompted us to explore lower group velocity structures operating at higher fundamental mode phase advances. The wakefield partitioning amongst the bands has been found to change markedly with increased phase advance. Here we report on general trends in the kick factor and associated wakefield band partitioning in dipole bands as a function of phase advance of the synchronous mode in linacs. These results are applicable to both TW (travelling wave) and SW (standing wave) structures

  4. ETA-II experiments for determining advanced radiographic capabilities of induction linacs

    International Nuclear Information System (INIS)

    Weir, J.T.; Caporaso, G.J.; Clark, J.C.; Kirbie, H.C.; Chen, Y.J.; Lund, S.M.; Westenskow, G.A.; Paul, A.C.

    1997-05-01

    LLNL has proposed a multi-pulsed, multi-line of sight radiographic machine based on induction linac technology to be the core of the advanced hydrotest facility (AHF) being considered by the Department of Energy. In order to test the new technologies being developed for AHF we have recommissioned the Experimental Test Accelerator (ETA II). We will conduct our initial experiments using kickers and large angle bending optics at the ETA II facility. Our current status and our proposed experimental schedule will be presented

  5. Mechanical Engineering of the Linac for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Bultman, N.K.; Chen, Z.; Collier, M.; Erickson, J.L.; Guthrie, A.; Hunter, W.T.; Ilg, T.; Meyer, R.K.; Snodgrass, N.L.

    1999-01-01

    The linac for the Spallation Neutron Source (SNS) Project will accelerate an average current of 1 mA of H - ions from 20 MeV to 1GeV for injection into an accumulator ring. The linac will be an intense source of H - ions and as such requires advanced design techniques to meet project technical goals as well as to minimize costs. The DTL, CCDTL and CCL are 466m long and operate at 805 MHz with a maximum H - input current of 28 mA and 7% rf duty factor. The Drift Tube Linac is a copper-plated steel structure using permanent magnetic quadrupoles. The Coupled-Cavity portions are brazed copper structures and use electromagnetic quads. RF losses in the copper are 80 MW, with total rf power supplied by 52 klystrons. Additionally, the linac is to be upgraded to the 2- and 4-MW beam power levels with no increase in duty factor. The authors give an overview of the linac mechanical engineering effort and discuss the special challenges and status of the effort

  6. Fermilab 200 MeV linac control system hardware

    International Nuclear Information System (INIS)

    Shea, M.F.

    1984-01-01

    This report is a description of the present Linac distributed control system that replaces the original Xerox computer and interface electronics with a network of 68000-based stations. In addition to replacing the obsolete Xerox equipment, goals set for the new system were to retain the fast response and interactive nature of the original system, to improve reliability, to ease maintenance, and to provide 15 Hz monitoring of all Linac parameters. Our previous experience with microcomputer installations showed that small, stand-alone control systems are rather straightforward to implement and have been proven to be reliable in operation, even in the severe environment of the 750-keV preaccelerator. The overall design of the Linac system incorporates the concept of many relatively small, stand-alone control systems networked together using an intercomputer communication network. Each station retains its local control system character but takes advantage of the network to allow an operator to interact with the entire Linac from any local console. At the same time, a link to the central computer system allows Host computers to also access parameters in the Linac

  7. Fermilab 200 MeV linac control system hardware

    Energy Technology Data Exchange (ETDEWEB)

    Shea, M.F.

    1984-01-01

    This report is a description of the present Linac distributed control system that replaces the original Xerox computer and interface electronics with a network of 68000-based stations. In addition to replacing the obsolete Xerox equipment, goals set for the new system were to retain the fast response and interactive nature of the original system, to improve reliability, to ease maintenance, and to provide 15 Hz monitoring of all Linac parameters. Our previous experience with microcomputer installations showed that small, stand-alone control systems are rather straightforward to implement and have been proven to be reliable in operation, even in the severe environment of the 750-keV preaccelerator. The overall design of the Linac system incorporates the concept of many relatively small, stand-alone control systems networked together using an intercomputer communication network. Each station retains its local control system character but takes advantage of the network to allow an operator to interact with the entire Linac from any local console. At the same time, a link to the central computer system allows Host computers to also access parameters in the Linac.

  8. Emittance reconstruction technique for the Linac4 high energy commissioning

    CERN Document Server

    Lallement, JB; Posocco, PA

    2012-01-01

    Linac4 is a new 160 MeV linear accelerator for negative Hydrogen ions (H-) presently under construction which will replace the 50 MeV proton Linac2 as injector for the CERN proton accelerator complex. Linac4 is 80 meters long and comprises a Low Energy Beam Transport line, a 3 MeV RFQ, a MEBT, a 50 MeV DTL, a 100 MeV CCDTL and a PIMS up to 160 MeV. The commissioning of the Linac is scheduled to start in 2013. It will be divided into several steps corresponding to the commissioning of the different accelerating structures. A temporary measurement bench will be dedicated to the high energy commissioning from 30 to 100 MeV (DTL tanks 2 and 3, and CCDTL). The commissioning of the PIMS will be done using the permanent equipment installed in between the end of the Linac and the main dump. This note describes the technique we will use for reconstructing the transverse emittances and the expected results.

  9. Heavy ion induction linac drivers for inertial confinement fusion

    International Nuclear Information System (INIS)

    Lee, E.P.; Hovingh, J.

    1988-10-01

    Intense beams of high energy heavy ions (e.g., 10 GeV Hg) are an attractive option for an ICF driver because of their favorable energy deposition characteristics. The accelerator systems to produce the beams at the required power level are a development from existing technologies of the induction linac, rf linac/storage ring, and synchrotron. The high repetition rate of the accelerator systems, and the high efficiency which can be realized at high current make this approach especially suitable for commercial ICF. The present report gives a summary of the main features of the induction linac driver system, which is the approach now pursued in the USA. The main subsystems, consisting of injector, multiple beam accelerator at low and high energy, transport and pulse compression lines, and final focus are described. Scale relations are given for the current limits and other features of these subsystems. 17 refs., 1 fig., 1 tab

  10. Design considerations for high-current superconducting ion linacs

    International Nuclear Information System (INIS)

    Delayen, J.R.; Bohn, C.L.; Micklich, B.J.; Roche, C.T.; Sagalovsky, L.

    1993-01-01

    Superconducting linacs may be a viable option for high-current applications such as fusion materials irradiation testing, spallation neutron source, transmutation of radioactive waste, tritium production, and energy production. These linacs must run reliably for many years and allow easy routine maintenance. Superconducting cavities operate efficiently with high cw gradients, properties which help to reduce operating and capital costs, respectively. However, cost-effectiveness is not the sole consideration in these applications. For example, beam impingement must be essentially eliminated to prevent unsafe radioactivation of the accelerating structures, and thus large apertures are needed through which to pass the beam. Because of their high efficiency, superconducting cavities can be designed with very large bore apertures, thereby reducing the effect of beam impingement. Key aspects of high-current cw superconducting linac designs are explored in this context

  11. Thirty-five years of drift-tube linac experience

    International Nuclear Information System (INIS)

    Knowles, H.B.

    1984-10-01

    The history of the drift-tube linear accelerator (linac) for the first 35 years of its existence is briefly reviewed. Both US and foreign experience is included. Particular attention is given to technological improvements, operational reliability, capital investment, and number of personnel committed to drift-tube linac (DTL) development. Preliminary data indicate that second- and third-generation (post-1960) DTLs have, in the US alone, operated for a combined total period of more than 75 machine-years and that very high reliability (>90%) has been achieved. Existing US drift-tube linacs represent a capital investment of at least $250 million (1983). Additional statistical evidence, derived from the proceedings of the last 11 linear accelerator conferences, supports the view that the DTL has achieved a mature technological base. The report concludes with a discussion of important recent advances in technology and their applications to the fourth generation of DTLs, many of which are now becoming operational

  12. A hot-spare injector for the APS linac

    International Nuclear Information System (INIS)

    Lewellen, J. W.

    1999-01-01

    Last year a second-generation SSRL-type thermionic cathode rf gun was installed in the Advanced Photon Source (APS) linac. This gun (referred to as ''gun2'') has been successfully commissioned and now serves as the main injector for the APS linac, essentially replacing the Koontz-type DC gun. To help ensure injector availability, particularly with the advent of top-up mode operation at the APS, a second thermionic-cathode rf gun will be installed in the APS linac to act as a hot-spare beam source. The hot-spare installation includes several unique design features, including a deep-orbit Panofsky-style alpha magnet. Details of the hot-spare beamline design and projected performance are presented, along with some plans for future performance upgrades

  13. Heavy-ion acceleration with a superconducting linac

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1988-01-01

    This year, 1988, is the tenth anniversary of the first use of RF superconductivity to accelerate heavy ions. In June 1978, the first two superconducting resonators of the Argonne Tandem-Linac Accelerator System (ATLAS) were used to boost the energy of a 19 F beam from the tandem, and by September 1978 a 5-resonator linac provided an 16 O beam for a nuclear-physics experiment. Since then, the superconducting linac has grown steadily in size and capability until now there are 42 accelerating structures and 4 bunchers. Throughout this period, the system was used routinely for physics research, and by now the total time with beam on target is 35,000 hours. Lessons learned from this long running experience and some key technical developments that made it possible are reviewed in this paper. 19 refs., 3 figs., 2 tabs

  14. Operational experience with the control scheme for IUAC linac booster

    International Nuclear Information System (INIS)

    Sahu, B.K.; Antony, J.; Mathuria, D.S.; Pandey, A.; Ghosh, S.; Mehta, R.; Rai, A.; Patra, P.; Choudhury, G.K.; Singh, K.; Ajith Kumar, B.P.; Kanjilal, D.; Roy, A.

    2009-01-01

    Accelerated beam from the first superconducting linear accelerator (linac) module of IUAC has been delivered to the user. The linac control scheme has worked successfully with the existing pelletron control scheme. Local RF control system consisting of Resonator controller and supporting RF modules are used for multipactoring conditioning, high power pulse conditioning and for the phase/amplitude locking of the superconducting resonators. Beam acceleration is done by adjusting the RF phase of each resonator with respect to master oscillator. The automation of control scheme is planned for smooth operation of linac with minimum human intervention. Python software support is added for writing automation routines in present control system software. An alternate tuning mechanism based on piezoelectric actuators has been successfully tested. (author)

  15. Overview and status of RF systems for the SSC Linac

    International Nuclear Information System (INIS)

    Mynk, J.; Grippe, J.; Cutler, R.I.; Rodriguez, R.

    1993-05-01

    The Superconducting Super Collider (SSC) Linear Accelerator (Linac) produces a 600-MeV, 35-μs, H-beam at a 10-Hz repetition rate. The beam is accelerated by a series of RF cavities. These consist of a Radio Frequency Quadrupole (RFQ), two bunchers, and four Drift Tube Linac (DTL) tanks at 427.617 MHz, and two bunchers, nine side-coupled Linac modules, and an energy compressor at 1282.851 MHz. The RFQ amplifier and the low-frequency buncher cavity amplifiers use gridded tubes, while the other cavities use klystron amplifier systems. The RF control system consists of a reference line and cavity feedback and feedforward loops for each amplifier. The RF amplifier system for each of these accelerator cavities is described, and the current status of each system is presented

  16. Argonne tandem as injector to a superconducting linac

    International Nuclear Information System (INIS)

    Yntema, J.L.; Den Hartog, P.K.; Henning, W.; Kutschera, W.

    1980-01-01

    The Argonne Tandem uses Pelletron chains, NEC accelerator tubes, and a dual closed-corona system. Its main function is to be an injector for a superconducting linear accelerator. As long as the transverse and longitudinal emittances are within the acceptance of the linac, the output beam quality of the tandem-linac system is essentially determined by the tandem. The sensitivity of the linac to the longitudinal emittance ΔEΔt of the incident beam makes the output beam quality dependent on the negative-ion velocity distribution in the source, transit-time effects in the tandem, molecular-beam dissociation, and stripper-foil uniformity. This paper discusses these beam-degrading effects

  17. Progress in the Development of the TOP Linac

    CERN Document Server

    Picardi, L

    2004-01-01

    The TOP Linac (Oncological Therapy with Protons), under development by ENEA and ISS is a sequence of three pulsed (5 msec, 300 Hz) linear accelerators: a 7 MeV, 425 MHz RFQ+DTL (AccSys Model PL-7), a 7–65 MeV, 2998 MHz Side Coupled Drift Tube Linac (SCDTL) and a 65–200 MeV, variable energy 2998 MHz Side Coupled Linac (SCL). The first SCDTL module is composed by 11 DTL tanks coupled by 10 side cavities. The tanks has modified to overcome vacuum leakage that occurred during brazing, and now the module has been completed, and is ready to be tested with protons. The 7 MeV injector has been recently installed in the ENEA Frascati laboratories for preliminary test, before being transferred to the main Oncologycal Hospital in Rome, Istituto Regina Elena.

  18. Status and experiece with the alignment of Linac4

    CERN Document Server

    Fuchs, Jean-Frederic

    2016-01-01

    LINAC4 (L4) is an H- linear accelerator that will deliver, for the High Luminosity LHC (HL-LHC) project requirements, a beam of protons at 160 MeV energy to the PS complex and then to the LHC. Its connection to the PS booster will take place during the Long Shutdown 2 (LS2) in 2019-2020 or earlier if any major failure of the LINAC2. The Linac4 project requires the precise alignment with a tolerance of about +/- 0.2 mm in both the horizontal and vertical planes, of elements along approximately 150 m beam line. This paper will give a status, an overview of the challenges of the alignment, the issues solved by the survey section, the techniques and methodology used to realise the survey activities over the last five years.

  19. An overview of BARC-TIFR pelletron linac facility

    International Nuclear Information System (INIS)

    Gupta, A.K.

    2014-01-01

    The 14UD Pelletron Accelerator at Mumbai has recently completed twenty five years of successful operation. The accelerator is primarily used for basic research in the fields of nuclear, atomic, condensed matter and material science. The superconducting Linac booster provides additional acceleration to the ions from Pelletron injector up to A∼60 region with E∼5 MeV/A. Further, an alternate injector system to the Superconducting LINAC booster is planned as an augmentation programme, comprising of a superconducting ECR ion source, room temperature RFQ and superconducting low-beta cavity resonators. This talk will provide an overview of the recent developmental activities carried out at the Pelletron Accelerator Facility, resulting in enhanced overall performance and uptime of the accelerator. The application oriented programs initiated at Pelletron Accelerator and the current status of the alternate injector system at the Pelletron-Linac facility will also be discussed. (author)

  20. An overview of BARC-TIFR Pelletron-Linac Facility

    International Nuclear Information System (INIS)

    Gupta, A. K.

    2015-01-01

    The 14UD Pelletron Accelerator at Mumbai has recently completed twenty five years of successful operation. The accelerator is primarily used for basic research in the fields of nuclear, atomic, condensed matter and material science. The superconducting Linac booster provides additional acceleration to the ions from Pelletron injector up to A~60 region with E~5 MeV/A. Further, an alternate injector system to the Superconducting LINAC booster is planned as an augmentation programme, comprising of a superconducting ECR ion source, room temperature RFQ and superconducting low-beta cavity resonators. This talk will provide an overview of the recent developmental activities carried out at the Pelletron Accelerator Facility, resulting in enhanced overall performance and uptime of the accelerator. The application oriented programs initiated at Pelletron Accelerator and the current status of the alternate injector system at the Pelletron-Linac facility will also be discussed. (author)

  1. Finite Element Thermal Study of the Linac4 Plasma Generatora

    CERN Document Server

    Faircloth, D; Kuchler, D; Lettry, L; Scrivens, R; CERN. Geneva. BE Department

    2010-01-01

    The temperature distribution and heat flow at equilibrium of the plasma generator of the RF-powered non-cesiated Linac4 H- ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW RF power, 2 Hz, 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of SPL, an extrapolation of the heat load towards 100 kW RF power, 50 Hz repetition rate and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in HP-SPL.

  2. Accelerator study note: An attempt of 1 GeV linac

    International Nuclear Information System (INIS)

    Kato, Takao.

    1987-01-01

    A hypothetical 1 GeV linac is described, including its structure (which includes an ion source, radio frequency quadrupole linac, drift type linac, and coupled cavity linac), criteria for optimized design, cost optimization, frequency dependability of high frequency electric power loss, tuning during operation, the general rf system, computer codes and example calculations, beam dynamics simulation, and reduction of energy spread through the use of a debuncher

  3. Approach of a failure analysis for the MYRRHA linac

    International Nuclear Information System (INIS)

    Carneiro, J.P.; Medeiros-Romao, L.; Salemne, R.; Vandeplassche, D.; Biarotte, J.L.; Bouly, F.; Uriot, D.

    2015-01-01

    The MYRRHA project currently under development at SCK-CEN (Mol, Belgium) is a subcritical research reactor that requires a 600 MeV proton accelerator as a driver. This linac is expected to produce a beam power of 1.5 MW onto a spallation target for the reactor to deliver a thermal power around 70 MW. Thermomechanical considerations of the spallation target set stringent requirements on the beam trip rate which should not exceed 40 trips/year for interruptions longer than three seconds. The 3 underlying principles in the design of the MYRRHA linac are elements redundancy (like the dual-injector), elements operation at de-rated values (like cavities operating at about 30% from their nominal operating points) and the fault tolerance concept, which allows the failure of a beamline component to be compensated by its neighbouring elements. Studies presented in this document show that in the event of a failure of the first cryo-module or the first quadrupole doublet the linac can resume nominal operation with a re-matched lattice. Since the fault tolerance procedure is expected to work more efficiently at higher energies (due to lower space charge effects) we can extrapolate from our studies that the MYRRHA linac is expected to operate with the failure of any cryo-module or quadrupole doublet in the main linac. A virtual accelerator-based control system is mandatory for the operation of the MYRRHA linac to ensure the very fast implementation (<3 seconds) of the fault tolerance procedure. The virtual accelerator uses a beam dynamics code (like TRACEWIN or TRACK) to compute the model of the real accelerator in operation and interacts with this later through the accelerator control command

  4. Safety aspects of pulsed YAYOI and Japan Linac Booster

    International Nuclear Information System (INIS)

    An, S.; Oka, Y.; Wakabayashi, J.

    1976-01-01

    The paper consists of two parts. The first part is concerned with safety aspects of pulsed YAYOI. Reactivity pulsed operation of YAYOI is performed with reactivity oscillating devices. Inherent safety characteristics due to dilation of metal fuel, a small amount of f.p. build up, reactor operation preserving fuel integrity and experience on transient experiments are the principal basis for safety assurance. Conditions for pulsed operation, namely, maximum allowable temperature, maximum number of repetition of pulsed operation and so on are derived from the consideration on the integrity of fuel. Instrumentation and control systems are reinforced by displacement meter in the core, interlock system, special timer for pulsed operation, additional scram conditions and reactivity meter. Accident analysis and safety evaluation indicate the conservative safety features of the facility. Concerning pulsed operation of YAYOI combined with Linac, special attention must be given to the design of Linac target placed in the core. In the second part are described the principal guide-lines and basic ideas for safety design of Japan Linac Booster (JLB). JLB is a U-Mo fueled and sodium cooled fast reactor with rotating reflector and Linac target in the core. The pulsed neutrons are injected into the core coincidentally with repetitive peaks of reactivity. Design of rotating reflector and Linac target system are the new and important safety problems not yet encountered in the usual sodium fast reactor design. The axis of the rotating reflector is horizontal, which avoids the collision of reflector block with core in the case of failure of rotating reflector. The separate cooling channels for target and the Linac electron beam control system are provided. Reactor shut down and power control systems must be carefully designed. Core meltdown and disassembly accident is considered as a hypothetical accident which is a basis for containment system design. (auth.)

  5. An energy recovery electron linac-on-ring collider

    International Nuclear Information System (INIS)

    Merminga, L.; Krafft, G.A.; Lebedev, V.A.; Ben-Zvi, I.

    2000-01-01

    We present the design of high-luminosity electron-proton/ion colliders in which the electrons are produced by an Energy Recovering Linac (ERL). Electron-proton/ion colliders with center of mass energies between 14 GeV and 100 GeV (protons) or 63 GeV/A (ions) and luminosities at the 10 33 (per nucleon) level have been proposed recently as a means for studying hadronic structure. The linac-on-ring option presents significant advantages with respect to: (1) spin manipulations (2) reduction of the synchrotron radiation load in the detectors (3) a wide range of continuous energy variability. Rf power and beam dump considerations require that the electron linac recover the beam energy. Based on extrapolations from actual measurements and calculations, energy recovery is expected to be feasible at currents of a few hundred mA and multi-GeV energies. Luminosity projections for the linac-ring scenario based on fundamental limitations are presented. The feasibility of an energy recovery electron linac-on-proton ring collider is investigated and four conceptual point designs are shown corresponding to electron to proton energies of: 3 GeV on 15 GeV, 5 GeV on 50 GeV and 10 GeV on 250 GeV, and for gold ions with 100 GeV/A. The last two designs assume that the protons or ions are stored in the existing RHIC accelerator. Accelerator physics issues relevant to proton rings and energy recovery linacs are discussed and a list of required R and D for the realization of such a design is presented

  6. Modeling high-Power Accelerators Reliability-SNS LINAC (SNS-ORNL); MAX LINAC (MYRRHA)

    International Nuclear Information System (INIS)

    Pitigoi, A. E.; Fernandez Ramos, P.

    2013-01-01

    Improving reliability has recently become a very important objective in the field of particle accelerators. The particle accelerators in operation are constantly undergoing modifications, and improvements are implemented using new technologies, more reliable components or redundant schemes (to obtain more reliability, strength, more power, etc.) A reliability model of SNS (Spallation Neutron Source) LINAC has been developed within MAX project and analysis of the accelerator systems reliability has been performed within the MAX project, using the Risk Spectrum reliability analysis software. The analysis results have been evaluated by comparison with the SNS operational data. Results and conclusions are presented in this paper, oriented to identify design weaknesses and provide recommendations for improving reliability of MYRRHA linear accelerator. The SNS reliability model developed for the MAX preliminary design phase indicates possible avenues for further investigation that could be needed to improve the reliability of the high-power accelerators, in view of the future reliability targets of ADS accelerators.

  7. Recent operation and modifications on the CPS - 50 MeV linac (old linac)

    International Nuclear Information System (INIS)

    Haseroth, H.; Tetu, P.

    1976-01-01

    Mainly to satisfy the requirements of the Booster synchrotron substantial improvements have been achieved on the Linac since 1970. The pulse length was increased to 100 μs and modifications on the rf system and on the pre-injector allowed the production of a stable beam without active feedback. These and further changes to the equipment have had a very beneficial effect on the fault rate. An emittance line providing one measurement per pulse and a spectrometer line furnishing ten spectra per pulse are important tools for beam adjustments. Without additional drastic changes to the machine beams of deuterons and alphas have been produced recently and successfully accelerated by the PS. (author)

  8. Design of the LINAC4 Transfer Line Quadrupole Electromagnets

    CERN Document Server

    Vanherpe, L

    2013-01-01

    Beam focusing in the various segments of the Linac4 Transfer Line is provided by quadrupole electromagnets. In total seventeen pulsed, air-cooled quadrupole electromagnets are required. They are made of laminated electrical steel yokes and coils wound from solid copper wire. All magnets have an aperture radius of 50 mm and are required to provide an integrated field gradient of 1.8 T over a magnetic length of 300 mm. This design report summarizes the main magnetic, electrical and mechanical design parameters of the Linac4 Transfer Line Quadrupole Magnets. The effect of the vacuum chamber on the magnetic field quality and the field delay is studied.

  9. On the e-linac-based neutron yield

    International Nuclear Information System (INIS)

    Bunatyan, G.G.; Nikolenko, V.G.; Popov, A.B.

    2010-01-01

    We treat neutron generating in high atomic number materials due to the photonuclear reactions induced by the Bremsstrahlung of an electron beam produced by linear electron accelerator (e-linac). The dependence of neutron yield on the electron energy and the irradiated sample size is considered for various sample materials. The calculations are performed without resort to the so-called 'numerical Monte Carlo simulation'. The acquired neutron yields are well correlated with the data asserted in investigations performed at a number of the e-linac-driven neutron sources

  10. Simplified RF power system for Wideroe-type linacs

    International Nuclear Information System (INIS)

    Fugitt, J.; Howard, D.; Crosby, F.; Johnson, R.; Nolan, M.; Yuen, G.

    1981-03-01

    The RF system for the SuperHILAC injector linac was designed and constructed for minimum system complexity, wide dynamic range, and ease of maintenance. The final amplifier is close coupled to the linac and operates in an efficient semilinear mode, eliminating troublesome transmission lines, modulators, and high level regulators. The system has been operated at over 250 kW, 23 MHz with good regulation. The low level RF electronics are contained in a single chassis adjacent to the RF control computer, which monitors all important operating parameters. A unique 360 0 phase and amplitude modular is used for precise control and regulation of the accelerating voltage

  11. Linac upgrade plan for the KEK B-Factory

    International Nuclear Information System (INIS)

    Enomoto, Atsushi; Anami, Shozo; Kamitani, Takuya; Hanaki, Hirofumi; Shidara, Tetsuo; Sato, Isamu

    1993-01-01

    In the KEK B-Factory plan, e+/e- collider rings with 3.5- GeV positions and 8-GeV electrons are being considered, and full-energy injection from the existing linac is required. The acceleration energy of the linac must be upgraded from 2.5 to 8 GeV. The most effective way has been searched from several points of view, such as the beam quality, ease of beam handling, and construction. This article describes the basic plan of the energy upgrade and recent progress regarding this project

  12. High intensity proton linac activities at Los Alamos

    International Nuclear Information System (INIS)

    Rusnak, B.; Chan, K.C.; Campbell, B.

    1998-01-01

    High-current proton linear accelerators offer an attractive alternative for generating the intense neutron fluxes needed for transmutations technologies, tritium production and neutron science. To achieve the fluxes required for tritium production, a 100-mA, 1700-MeV cw proton accelerator is being designed that uses superconducting cavities for the high-energy portion of the linac, from 211 to 1,700 MeV. The development work supporting the linac design effort is focused on three areas: superconducting cavity performance for medium-beta cavities at 700 MHz, high power rf coupler development, and cryomodule design. An overview of the progress in these three areas is presented

  13. Linac design study for an intense neutron-source driver

    International Nuclear Information System (INIS)

    Lynch, M.T.; Browman, A.; DeHaven, R.; Jameson, R.; Jason, A.; Neuschaefer, G.; Tallerico, P.; Regan, A.

    1993-01-01

    The 1-MW spallation-neutron source under design study at Los Alamos is driven by a linac-compressor-ring scheme that utilizes a large portion of the existing Los Alamos Meson Physics Facility (LAMPF) linac, as well as the facility infrastructure. The project is referred to as the National Center for Neutron Research (NCNR). A second phase of the proposal will upgrade the driver power to 5 MW. A description of the 1-MW scheme is given in this paper. In addition, the upgrade path to the substantial increase of beam power required for the 5 MW scenario is discussed

  14. Optimization of the cooling power distribution in a superconducting linac

    International Nuclear Information System (INIS)

    Wendl, C.M.; Noe, J.W.

    1996-01-01

    The benefits of setting the resonators in a superconducting heavy-ion linac to a certain optimum distribution of cooling power have been evaluated in terms of the total acceleration such a distribution may produce, compared to a distribution in which each resonator dissipates power equally. The optimum power distribution can be expressed in closed form in certain simplified cases, but the general case is solved by equalizing the 'marginal power cost' of the resonators by iteration in a computer simulation. For the Stony Brook linac an additional possible acceleration of several percent is thus predicted for typical beams. (author)

  15. Radio frequency quadrupole linac for the superconducting super collider

    International Nuclear Information System (INIS)

    Schrage, D.L.; Young, L.M.; Clark, W.L.; Billen, J.H.; DePaula, R.F.; Naranjo, A.C.; Neuschaefer, G.H.; Roybal, P.L.; Stovall, J.E.; Ray, K.; Richter, R.

    1993-01-01

    A 2.5 MeV, 428 MHz radio frequency quadrupole (RFQ) linac has been designed and fabricated by the Los Alamos National Laboratory and GAR Electroforming for the Superconducting Super Collider Laboratory. This device is a two segment accelerator fabricated from tellurium-copper (CDA14500) vane/cavity quadrants which are joined by electroforming. The structure incorporates an integral vacuum jacket and has no longitudinal rf or mechanical joints. The SSC RFQ linac is an extension of the design of the 1.0 MeV RFQ which was successfully flown on the BEAR Project. (orig.)

  16. Beam position monitor for energy recovered linac beams

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Thomas; Evtushenko, Pavel

    2017-06-06

    A method of determining the beam position in an energy recovered linac (ERL). The method makes use of in phase and quadrature (I/Q) demodulation techniques to separate the pickup signal generated by the electromagnetic fields generated by the first and second pass beam in the energy recovered linac. The method includes using analog or digital based I/Q demodulation techniques in order to measure the relative amplitude of the signals from a position sensitive beam pickup such as a button, strip line or microstripline beam position monitor.

  17. Optical laser systems at the Linac Coherent Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Minitti, Michael P.; Robinson, Joseph S.; Coffee, Ryan N.; Edstrom, Steve; Gilevich, Sasha; Glownia, James M.; Granados, Eduardo; Hering, Philippe; Hoffmann, Matthias C.; Miahnahri, Alan; Milathianaki, Despina; Polzin, Wayne; Ratner, Daniel; Tavella, Franz; Vetter, Sharon; Welch, Marc; White, William E.; Fry, Alan R., E-mail: alanfry@slac.stanford.edu [Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2015-04-22

    This manuscript serves as a reference to describe the optical laser sources and capabilities at the Linac Coherent Light Source. Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS.

  18. Tranverse beam break up in a periodic linac

    International Nuclear Information System (INIS)

    Decker, G.; Wang, J.M.

    1987-01-01

    The problem of cumulative beam break up in a periodic linac for a general impedance is discussed, with the effects of acceleration included. The transverse equations of motion for a set of identical point like bunches moving along the length of the linac are cast into a simple form using a smooth approximation. This results in a working formula that is used to analyze beam breakup. Explicit expressions for the transverse motion in the case of a single resonance impedance are found using saddle point integration. This is done first with no external focusing, and again in the strong focusing limit

  19. Micro-SHINE Uranyl Sulfate Irradiations at the Linac

    Energy Technology Data Exchange (ETDEWEB)

    Youker, Amanda J. [Argonne National Lab. (ANL), Argonne, IL (United States); Kalensky, Michael [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Schneider, John [Argonne National Lab. (ANL), Argonne, IL (United States); Byrnes, James [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-08-01

    Peroxide formation due to water radiolysis in a uranyl sulfate solution is a concern for the SHINE Medical Technologies process in which Mo-99 is generated from the fission of dissolved low enriched uranium. To investigate the effects of power density and fission on peroxide formation and uranyl-peroxide precipitation, uranyl sulfate solutions were irradiated using a 50-MeV electron linac as part of the micro-SHINE experimental setup. Results are given for uranyl sulfate solutions with both high and low enriched uranium irradiated at different linac powers.

  20. Practical test of the LINAC4 RF power system

    CERN Document Server

    Schwerg, N

    2011-01-01

    The high RF power for the Linac4 accelerating structures will be generated by thirteen 1.3 MW klystrons, previously used for the CERN LEP accelerator, and six new klystrons of 2.8 MW all operating at a frequency of 352.2 MHz. The power distribution scheme features a folded magic tee feeding the power from one 2.8 MW klystron to two LEP circulators. We present first results from the Linac4 test place, validating the approach and the used components as well as reporting on the klystron re-tuning activities.

  1. Low power rf system for the ALS Linac

    International Nuclear Information System (INIS)

    Lo, C.C.; Taylor, B.; Lancaster, H.

    1991-05-01

    The Linear Accelerator (Linac) in the Advanced Light Source (ALS) is designed to provide either single or multiple bunchers of 50 MeV electrons for the booster synchrotron. Three cavities are used in the Linac for electron bunching. The two subharmonic bunching cavities operate at 124.914 MHz and 499.654 MHz respectively. The S Band buncher operates at 2.997924 GHz. The low level RF system includes a master signal source, RF burst generators, signal phase control, timing trigger generators and a water temperature control system. The design and performance of the system will be described. 7 refs., 3 figs

  2. Estimates of dispersive effects in a bent NLC Main Linac

    International Nuclear Information System (INIS)

    Syphers, Michael; Michelotti, Leo

    2000-01-01

    An alternative being considered for the Next Linear Collider (NLC) is not to tunnel in a straight line but to bend the Main Linac into an arc so as to follow a gravitational equipotential. The authors begin here an examination of the effects that this would have on vertical dispersion, with its attendant consequences on synchrotron radiation and emittance growth by looking at two scenarios: a gentle continuous bending of the beam to follow an equipotential surface, and an introduction of sharp bends at a few sites in the linac so as to reduce the maximum sagitta produced

  3. ETL linac facility and free-electron lasers

    International Nuclear Information System (INIS)

    Yamazaki, T.; Noguchi, T.; Mikado, T.; Sugiyama, S.; Yamada, K.; Chiwaki, M.; Ohgaki, H.; Suzuki, R.; Sei, N.

    1993-01-01

    An outline is presented of the recent development on the ETL (Electro-technical Laboratory) electron-linac facility and storage-ring FELs (free-electron lasers). Some modifications including the injection system have been made to the linac. Four storage rings are working very well. The TERAS FEL system has been shut down after the successful oscillation around 590 nm. The new NIJI-IV FEL system has been proven to work well, and the current tunable wavelength range is over 100 nm (488-595 nm). Preparatory experiments on the FEL at shorter wavelength are underway. (author)

  4. Design and construction of the main linac module for the superconducting energy recovery linac project at Cornell

    Energy Technology Data Exchange (ETDEWEB)

    Eichhorn, R.; Bullock, B.; He, Y.; Hoffstaetter, G.; Liepe, M.; O' Connell, T.; Quigley, P.; Sabol, D.; Sears, J.; Smith, E.; Veshcherevich, V. [Cornell Laboratory for Accelerator-based Science and Education (CLASSE), Cornell University, 161 Synchrotron Drive, Ithaca, NY 14853 (United States)

    2014-01-29

    Cornell University has been designing and building superconducting accelerators for various applications for more than 50 years. Currently, an energy-recovery linac (ERL) based synchrotron-light facility is proposed making use of the existing CESR facility. As part of the phase 1 R and D program funded by the NSF, critical challenges in the design were addressed, one of them being a full linac cryo-module. It houses 6 superconducting cavities- operated at 1.8 K in continuous wave (CW) mode - with individual HOM absorbers and one magnet/ BPM section. Pushing the limits, a high quality factor of the cavities (2⋅10{sup 10}) and high beam currents (100 mA accelerated plus 100 mA decelerated) are targeted. We will present the design of the main linac cryo-module (MLC) being finalized recently, its cryogenic features and report on the status of the fabrication which started in late 2012.

  5. Obtaining the Bunch Shape in a Linac from Beam Spectrum Measurements

    International Nuclear Information System (INIS)

    Bane, Karl LF

    1999-01-01

    In linacs with high single-bunch charge, and tight tolerances for energy spread and emittance growth, controlling the short-range wakefield effects becomes extremely important. The effects of the wakefields, in turn, depend on the bunch length and also on the bunch shape. It was shown in the linac of the Stanford Linear Collider (SLC), for example, that by shaping the bunch, the final rms energy spread could be greatly reduced, compared to for the standard Gaussian bunch shape[1]. Therefore, in machines with high single-bunch charge, a method of measuring bunch shape can be an important beam diagnostic. In a linac with low single-bunch charge, the longitudinal bunch shape can be obtained relatively easily from a single measurement of the beam's final energy spectrum, provided that the final to initial energy ratio is large. One merely shifts the average phase of the beam, so that it rides off-crest sufficiently to induce an energy variation that is monotonic with longitudinal position. Then, by knowing the initial and final energies, the rf wave number, and the average beam phase, one can directly map the spectrum into the bunch shape. In a linac with high single-bunch charge, however, due to the effect of the longitudinal wakefield, this method either does not work at all, or it requires such a large shift in beam phase as to become impractical. In earlier work[2],[3] it was shown that, even when wakefields are important, if one measures the final beam spectrum for two different (properly chosen) values of beam phase, then one can again obtain the bunch shape, and--as a by-product--also the form of the wakefield induced voltage; this method was then illustrated using data from the linac of the SLC. These SLC measurements, however, had been performed with the machine in a special configuration, where the current was low; in addition, the noise the data was low and the measured spectra were smooth distributions. Under normal SLC conditions, however, the currents

  6. Progress of electron gun systems for the e-/e+ linac at KEK

    International Nuclear Information System (INIS)

    Ohsawa, S.; Ogawa, Y.; Otake, Y.; Yokota, M.; Fukuda, S.; Saito, Y.; Enomoto, A.; Azuma, O.; Iwata, H.; Asami, A.

    1989-01-01

    Several improvements have been made in the electron gun systems of the 2.5 GeV PF linac and the Positron Generator. In the electron gun system of the PF linac, the vacuum system and the focusing system have been modified, and the anode current was increased. In the case of a short pulse beam with a width of 2 ns, the anode current has been more than 200 mA for about a year with a constant pulse voltage output of a grid pulser. Injection time of the electron beam into the Accumulation Ring of TRISTAN has been normally less than 10 s. Meanwhile in the electron gun system of the Positron Generator, improvements have been made mainly in the following two points; (1) a raise of injection voltage of the gun from 115 kV to 150 kV, which was made possible by using a newly designed insulator, and (2) an increase of pulse voltage output of a grid pulser by use of new transistors with a high slew rate. As a result of these improvements, a maximum anode peak current of 12 A with a pulse width of 4 ns can be obtained, which satisfies the design parameters of the gun system. 7 refs., 8 figs

  7. Sawtooth-wave prebuncher with dual-gaps in Linac injector for HIRFL-SSC

    Science.gov (United States)

    Zhang, Xiaohu; Yuan, Youjin; Xia, Jiawen; Yin, Xuejun; Jin, Peng; Xu, Zhe; Du, Heng; Li, Zhongshan; Qiao, Jian; Wang, Kedong

    2018-01-01

    An RFQ structure is normally composed of radial matcher, shaper, gentle buncher and accelerator section with changing cell geometry. Bunching is started in the shaper, and adiabatic bunching is done in gentle buncher section. The beam preforms from DC beam to bunch beam through the RFQ and the longitudinal emittance for the ions linacs is defined initially in the RFQ, in which the beam bunch has been shaped. In the present SSC-Linac injector, an RFQ has been designed to accelerate the continuous beam from 3.728 keV/u to 143 keV/u. The heavy ions beam is injected into the SSC (Separated Sector Cyclotron) with the kinetic energy of 1.025 MeV/u after four IH DTLs. The rf frequency of the SSC is 13.417 MHz, and the frequency of the heavy ions RFQ is set to four times of the rf frequency of the SSC. In order to increase the longitudinal capture efficiency of the SSC and suppress the longitudinal emittance at the exit of RFQ, an external MHB (Multi-Harmonics Buncher) is proposed in front of the RFQ. The fundamental frequency of the MHB is the same as the rf frequency of the cyclotron. The scheme of dual-gaps prebuncher with the sawtooth waveform is firstly carried out through multi-harmonics synthetic technology. The multi-particle beam dynamic simulations of the MHB have been done by the BEAMPATH code.

  8. Radiation induced currents in MRI RF coils: application to linac/MRI integration

    Science.gov (United States)

    Burke, B.; Fallone, B. G.; Rathee, S.

    2010-02-01

    The integration of medical linear accelerators (linac) with magnetic resonance imaging (MRI) systems is advancing the current state of image-guided radiotherapy. The MRI in these integrated units will provide real-time, accurate tumor locations for radiotherapy treatment, thus decreasing geometric margins around tumors and reducing normal tissue damage. In the real-time operation of these integrated systems, the radiofrequency (RF) coils of MRI will be irradiated with radiation pulses from the linac. The effect of pulsed radiation on MRI radio frequency (RF) coils is not known and must be studied. The instantaneous radiation induced current (RIC) in two different MRI RF coils were measured and presented. The frequency spectra of the induced currents were calculated. Some basic characterization of the RIC was also done: isolation of the RF coil component responsible for RIC, dependence of RIC on dose rate, and effect of wax buildup placed on coil on RIC. Both the time and frequency characteristics of the RIC were seen to vary with the MRI RF coil used. The copper windings of the RF coils were isolated as the main source of RIC. A linear dependence on dose rate was seen. The RIC was decreased with wax buildup, suggesting an electronic disequilibrium as the cause of RIC. This study shows a measurable RIC present in MRI RF coils. This unwanted current could be possibly detrimental to the signal to noise ratio in MRI and produce image artifacts.

  9. ANU LINAC upgrade using multi-stub resonators

    Indian Academy of Sciences (India)

    LINAC development work at ANU is currently aimed at improving ... current through the rf joint at the base of the outer wall and so increasing joint losses. The ... The stub geometry was developed with a help of Superfish/Poisson software [8].

  10. NSRL 200 MeV linac beam energy stabilization system

    International Nuclear Information System (INIS)

    Huang Guirong; Pei Yuanji; Dong Sai

    2001-01-01

    By using the computer image processing technology and RF phase auto-shifting system, the ESS (Energy Stabilization System) was applied to 200 MeV Linac. the ESS adjusts beam energy automatically in a range of +-4 MeV. After adjustment beam energy stability is improved to +-6%

  11. Reliability model of SNS linac (spallation neutron source-ORNL)

    International Nuclear Information System (INIS)

    Pitigoi, A.; Fernandez, P.

    2015-01-01

    A reliability model of SNS LINAC (Spallation Neutron Source at Oak Ridge National Laboratory) has been developed using risk spectrum reliability analysis software and the analysis of the accelerator system's reliability has been performed. The analysis results have been evaluated by comparing them with the SNS operational data. This paper presents the main results and conclusions focusing on the definition of design weaknesses and provides recommendations to improve reliability of the MYRRHA ( linear accelerator. The reliability results show that the most affected SNS LINAC parts/systems are: 1) SCL (superconducting linac), front-end systems: IS, LEBT (low-energy beam transport line), MEBT (medium-energy beam transport line), diagnostics and controls; 2) RF systems (especially the SCL RF system); 3) power supplies and PS controllers. These results are in line with the records in the SNS logbook. The reliability issue that needs to be enforced in the linac design is the redundancy of the systems, subsystems and components most affected by failures. For compensation purposes, there is a need for intelligent fail-over redundancy implementation in controllers. Enough diagnostics has to be implemented to allow reliable functioning of the redundant solutions and to ensure the compensation function

  12. Charge measurement system at 100 MeV linac

    International Nuclear Information System (INIS)

    Li Dongmei; Chinese Academy of Sciences, Beijing; Yin Chongxian; Ye Kairong

    2005-01-01

    A charge measurement system of 100 Mev linac is introduced in this paper. After describing the characteristics and functions of the system's components, the authors analyze the methods of data processing and systematic error in detail. Basing on these, the authors get system resolution in the lab. The actual measurement results are presented at last. (authors)

  13. Status of the SNS superconducting linac and future plan

    International Nuclear Information System (INIS)

    Kim, Sang-Ho

    2008-01-01

    The use of superconducting radiofrequency (SRF) cavities in particle accelerator is becoming more widespread. Among the projects that make use of that technology is the Spallation Neutron Source, where H- ions are accelerated to about 1 GeV, mostly making use of niobium elliptical cavities. SNS generates neutrons by the spallation reaction with the accelerated short (about 700 ns) sub-bunches of protons, which will in turn allow probing structural and magnetic properties of new and existing materials. The SNS superconducting linac is the largest application of RF superconductivity to come on-line in the last decade and has been operating with beam for almost two years. As the first operational pulsed superconducting linac, many of the aspects of its performance were unknown and unpredictable. A lot of experiences and data have been gathered on the pulsed behavior of cavities and cryomodules at various repetition rates and at various temperatures during the commissioning of its components and beam operations. This experience is of great value in determining future optimizations of SNS as well in guiding in the design and operation of future pulsed superconducting linacs. The testing of the superconducting cavities, the operating experience with beam, the performance of the superconducting linac and the future plans will be presented.

  14. Optimization of steering elements in the RIA driver linac

    International Nuclear Information System (INIS)

    Lessner, E. S.; Aseev, V. S.; Ostroumov, P. N.; Physics

    2005-01-01

    The driver linac of the projected RIA facility is a versatile accelerator, a 1.4-GV, CW superconducting (SC) linac designed to simultaneously accelerate several heavy-ion charge states, providing beams from proton to uranium at 400 MeV/u at power levels at a minimum of 100 kW and up to 400 kW for most beams. Acceleration of multiple-charge-state uranium beams places stringent requirements on the linac design. A steering algorithm was derived that fulfilled the driver's real estate requirements, such as placement of steering dipole coils on SC solenoids and of beam position monitors outside cryostats, and beam-dynamics requirements, such as coupling effects induced by the focusing solenoids. The algorithm has been fully integrated into the tracking code TRACK and it is used to study and optimize the number and position of steering elements that minimize the multiple-beam centroid oscillations and preserve the beam emittance under misalignments of accelerating and transverse focusing elements in the driver linac

  15. Beam dynamics of alternating-phase-focused linac

    CERN Document Server

    Iwata, Y; Kapin, V

    2004-01-01

    A simple method to find an array of synchronous phases for alternating-phase-focused (APF) linacs is presented. The phase array is described with a smooth function having free parameters. With a set of the parameters, a simulation on the beam dynamics was made and distributions of the six-dimensional phase spaces were calculated for each set of the parameters. The parameters were varied, and numbers of the simulations have been performed. An optimum set of the parameters were determined so that the simulations of the beam dynamics yield large acceptances and small emittances of the extracted beams. Since the APF linac can provide both axial and radial stability of beams just with the rf acceleration-field, no additional focusing element inside of drift tubes are necessary. Comparing with conventional linacs having focusing elements, it has advantage in construction and operation costs as well as its acceleration rate. Therefore, the APF linacs would be suited for an injector of medical synchrotrons. A practic...

  16. Design study on an intense heavy-ion linac system

    International Nuclear Information System (INIS)

    Okamura, M.; Oguri, Y.; Takahashi, Y.; Hattori, T.; Takeda, O.; Satoh, K.; Tanabe, Y.

    1992-01-01

    A four-vane RFQ cavity is designed for an intense heavy-ion linac system. RFQ-vanes with small tip curvatures are applied in order to improve the RF power efficiency. Beam optical and RF parameters are investigated by beams of numerical methods. Using a scale model, the cavity structure is experimentally optimized. (Author) 7 refs., 4 figs

  17. rf quadrupole linac: a new low-energy accelerator

    International Nuclear Information System (INIS)

    Hamm, R.W.; Crandall, K.R.; Fuller, C.W.

    1980-01-01

    A new concept in low-energy particle accelerators, the radio-frequency quadrupole (RFQ) linac, is currently being developed at the Los Alamos National Scientific Laboratory. In this new linear accelerating structure both the focusing and accelerating forces are produced by the rf fields. It can accept a high-current, low-velocity dc ion beam and bunch it with a high capture efficiency. The performance of this structure as a low-energy linear accelerator has been verified with the successful construction of a proton RFQ linac. This test structure has accelerated 38 mA of protons from 100 keV to 640 keV in 1.1 meters with a capture efficiency greater than 80%. In this paper a general description of the RFQ linac and an outline of the basic RFQ linac design procedure are presented in addition to the experimental results from the test accelerator. Finally, several applications of this new accelerator are discussed

  18. Medical application and its promotion of X-band linacs

    International Nuclear Information System (INIS)

    Uesaka, Mitsuru; Dobashi, Katsuhiro; Kaneyasu, Tatsuo

    2005-01-01

    This article presents the current status of the development of the monochromatic tunable hard X-ray source by the X-band linac and YAG leasers. New medical applications such as 2 colors CT and Drug Delivery System (DDS) are planned. Finally, the virtual laboratory for the distribution of the system to the society is discussed. (author)

  19. Failure Modes Analysis for the MSU-RIA Driver Linac

    CERN Document Server

    Wu, Xiaoyu; Gorelov, Dmitry; Grimm, Terry L; Marti, Felix; York, Richard

    2005-01-01

    Previous end-to-end beam dynamics simulation studies* using experimentally-based input beams including alignment and rf errors and variation in charge-stripping foil thickness have indicated that the Rare Isotope Accelerator (RIA) driver linac proposed by MSU has adequate transverse and longitudinal acceptances to accelerate light and heavy ions to final energies of at least 400 MeV/u with beam powers of 100 to 400 kW. During linac operation, equipment loss due to, for example, cavity contamination, availability of cryogens, or failure of rf or power supply systems, will lead to at least a temporary loss of some of the cavities and focusing elements. To achieve high facility availability, each segment of the linac should be capable of adequate performance even with failed elements. Beam dynamics studies were performed to evaluate the linac performance under various scenarios of failed cavities and focusing elements with proper correction schemes, in order to prove the flexibility and robustness of the driver ...

  20. Linac4, a New Injector for the CERN PS Booster

    CERN Document Server

    Garoby, R; Gerigk, F; Hanke, K; Lombardi, A; Pasini, M; Rossi, C; Sargsyan, E; Vretenar, M

    2006-01-01

    The first bottle-neck towards higher beam brightness in the LHC injector chain is due to space charge induced tune spread at injection into the CERN PS Booster (PSB). A new injector called Linac4 is proposed to remove this limitation. Using RF cavities at 352 and 704 MHz, it will replace the present 50 MeV proton Linac2, and deliver a 160 MeV, 40 mA H- beam. The higher injection energy will reduce space charge effects by a factor of 2, and charge exchange will drastically reduce the beam losses at injection. Operation will be simplified and the beam brightness required for the LHC ultimate luminosity should be obtained at PS ejection. Moreover, for the needs of non-LHC physics experiments like ISOLDE, the number of protons per pulse from the PSB will increase by a significant factor. This new linac constitutes an essential component of any of the envisaged LHC upgrade scenarios. It is also designed to become the low energy part of a future 3.5 GeV, multi-megawatt superconducting linac (SPL). The present desig...

  1. Heavy-ion LINAC development for the US RIA project

    Indian Academy of Sciences (India)

    obtain 403 MeV/u the driver LINAC has to have two strippers. Three different sections ... The RFQ and multi-harmonic buncher are specially designed in order to provide very low ..... The colors represent three different types of cavities. Table 6.

  2. Conceptual designs of beam choppers for RFQ linacs

    International Nuclear Information System (INIS)

    Nath, S.; Stevens, S.R. Jr.; Wangler, T.P.

    1995-01-01

    A design study at Los Alamos of a linac/accumulator ring facility for a pulsed neutron spallation source calls for an H - beam with a chopped structure of approximately 200-ns beam-free segments every 600-ns. The required angular impulse can easily be provided with existing pulse power technology and traveling wave structures with a transverse electric field similar to those now available. The deflected beam is then restored by suitable collimation. Chopping is relatively easily done at sufficiently low energies, where the beam is easily deflected, and beam powers are not too large. However, the energy should be high enough so that the space-charge blow-up of the beam can be controlled with adequate focusing. LAMPF presently uses a traveling-wave beam chopper at 750 keV, before injection into the drift tube linac (DTL). In the new linac designs, a radiofrequency quadrupole (RFQ) linac would typically bunch and accelerate the high intensity H - beam from 100 keV to 7 MeV. In this paper, the authors present concepts for beam-chopper systems both before and after the RFQ. The beam-optics designs are presented, together with numerical simulation results

  3. Conceptual Design for the New RPI 2020 Linac

    Energy Technology Data Exchange (ETDEWEB)

    Adolphsen, C.; Bane, K.; Dolgashev, V.; Jensen, A.; Haase, A.; Jongewaard, E.; Kemp, M.; Krasnykh, A.; Lewandowski, J.; Li, Z.; Neilson, J.; Pearson, C.; Tantawi, S.; Wang, J.; Yeremian, A.D.; /SLAC; Brand, P.; Danon, Y.; /Rensselaer Polytech. Inst.; Epping, B.; Donovan, T.; Block, R.; Leinweber, G.; /Knolls Atomic Power Lab.

    2014-10-29

    The Rensselaer Polytechnic Institute (RPI) spectrometer is an installation based on an L-band linear accelerator designed and installed many decades ago. While this installation has served many important experiments over the decades, a new more powerful and more flexible linac to serve a wider range of experiments is envisioned as an upgrade to the existing installation by 2020.

  4. Full power to the first Linac4 module

    CERN Multimedia

    Francesco Poppi

    2010-01-01

    Since last week the first of a total of 23 accelerating structures for Linac4 has been undergoing high-power tests. Although still a prototype, this structure is destined to be the first of the 12 PIMS cavities to be installed in the Linac4 tunnel and it has been completely designed, developed and constructed at CERN.   The PIMS prototype. The new Linac4 has 4 different types of accelerating structures. The PI-Mode Structures (PIMS) are the last stage and are designed to accelerate protons up to 160 MeV. “PIMS have never before been used to accelerate protons”, explains Frank Gerigk, the project engineer responsible for the Linac4 accelerating structures. “In LEP, they were used to accelerate electrons, and now we have modified them and improved several design features to make them suitable for protons”. The first prototype was entirely manufactured in the CERN workshop. Due to the size of the pieces it was difficult to achieve and preserve the required to...

  5. Linac4: injecting new life into the LHC

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    Construction work is nearing completion on the ion source for Linac4, the new linear accelerator that forms part of the LHC injector upgrade programme. Here we find out more about this essential component of the accelerator chain, designed and built at CERN.     The image shows the Linac4 H- source. The red light is the alpha line of the visible hydrogen emission spectrum. The ion source is a key component of Linac4, the linear accelerator that from 2018 will supply H- ions (hydrogen atoms with an extra electron) at 160 MeV for injection into the accelerator complex. As the only ion source at CERN, Linac4 must be highly reliable, which requires a full understanding of the production mechanisms, the simulation of physical processes and the validation of those processes through experimentation. “This source is the result of much fruitful collaboration,” says Jacques Lettry of the BE department. “Its design was inspired by the many sources of th...

  6. 200 MeV RF linac for synchrotron injection

    International Nuclear Information System (INIS)

    Whitham, K.; Anamkath, H.; Lyons, S.; Manca, J.; Miller, R.; Treas, P.; Zante, T.; Miller, R.

    1992-01-01

    Construction has been completed on an electron linear accelerator for the Brookhaven National Laboratory. This accelerator will be used for the injection of a 200 MeV electron beam into a synchrotron for lithography experiments. This paper describes the conceptual design of the linac, its e-gun pulser, and its control and timing systems. 3 figs., ref

  7. A Study of Failure Modes in the ILC Main Linac

    CERN Document Server

    Eliasson, Peder; Krücker, Dirk; Latina, Andrea; Poirier, Freddy; Schulte, Daniel; Walker, Nicholas John; Xia, Guoxing

    2006-01-01

    Failures in the ILC can lead to beam loss or even damage the machine. In the paper quadrupole failures and errors in the klystron phase are being investigated and the impact on the machine protection is being considered for the main linac.

  8. Design and analysis of X-band femtosecond linac

    Energy Technology Data Exchange (ETDEWEB)

    Uesaka, M; Kozawa, T; Takeshita, A; Kobayashi, T; Ueda, T; Miya, K [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1997-03-01

    Femtosecond quantum phenomena research project is proposed at Nuclear Engineering Research Laboratory, University of Tokyo. The research facility consists of an X-band (11.424GHz) femtosecond electron linac, a femtosecond wavelength tunable laser, two S-band (2.856GHz) picosecond electron linacs and measuring equipments. Especially, we aim to generate a 100 fs (FWHM) electron single bunch with more than 1 nC at the X-band femtosecond linac. Ultrafast processes in radiation physics, chemistry, material science and microscopic electromagnetic phenomena are going to be analyzed there. Here the design and analysis of an X-band femtosecond linac is presented. The simulation of electron dynamics is carried out including magnetic pulse compression by using PARMELA and SUPERFISH. It is found by the simulation that the 600 ps (tail-to-tail) electron emission from a 200 kV thermionic gun can be bunched and compressed to 110 fs (FWHM) with the charge of 0.8 nC which gives 7.3 kA. We plan to use one high power X-band klystron which can supply 60 MW with more than 200 ns pulse duration. The flatness of plateau of the pulse should be 0.2% for stable ultrashort bunch generation. (author)

  9. New control system for the KEK-linac

    International Nuclear Information System (INIS)

    Kamikubota, N.; Furukawa, K.; Nakahara, K.; Abe, I.; Akimoto, H.

    1993-01-01

    New control system for the KEK-Linac has been developed. Unix-based workstations and VME-bus computers are introduced. They are inter-connected with an Ethernet, which is used as a high-speed data-exchange network. New system will start the operation after October 1993. (author)

  10. The quarter wave resonator as a superconducting linac element

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Brennan, J.M.

    1983-01-01

    The electrical and mechanical properties of quarter wave resonators are derived. A procedure for optimal design of a quarter wave resonator for use in a superconducting heavy ion linac is given. It is concluded that a quarter wave resonator has significant advantages for this application. (orig.)

  11. Improved performance of the control scheme for IUAC superconducting Linac

    International Nuclear Information System (INIS)

    Sahu, B.K.; Suman, S.K.; Kumar, R.

    2015-01-01

    Since many years energized ion beams from linac are being delivered routinely for scheduled experiments using all the three accelerating modules of linac along with super buncher and rebuncher. Major efforts are dedicated to improve the performance of the control scheme to minimise the down time of the linac during operation. Earlier, a number of developments were carried out to improve the dynamics of the control scheme. The most significant of them is the piezoelectric actuator based tuning mechanism which is implemented in all the operational resonators of second and third accelerating modules of superconducting linac. This has helped us to bridge the gap between the accelerating fields achieved during Q measurement at 6 W of helium power and during phase locking of the resonator during beam operation at a given RF power (∼120W). The piezoelectric actuator based tuner is also instrumental to reduce the unlocking rate of the resonators. Pulse width modulation (PWM) control based helium gas operated tuner is implemented in few resonators to improve phase locking performance. CAMAC based distributed control scheme is upgraded to VME based distributed control without changing the existing client interface to maintain uniformity between the Pelletron and linac control. Python code support has been implemented to protect the resonators against high forward power during unlocking. This is also integrated with the display status of the resonators for monitoring. A frequency to voltage converter is incorporated in control scheme to monitor the frequency error. This has helped us to develop a scheme for automatic phase locking of the cavities using piezoelectric actuator based tuner control. (author)

  12. Beam halo in high-intensity hadron linacs

    Energy Technology Data Exchange (ETDEWEB)

    Gerigk, F

    2006-12-21

    This document aims to cover the most relevant mechanisms for the development of beam halo in high-intensity hadron linacs. The introduction outlines the various applications of high-intensity linacs and it will explain why, in the case of the CERN Superconducting Proton Linac (SPL) study a linac was chosen to provide a high-power beam, rather than a different kind of accelerator. The basic equations, needed for the understanding of halo development are derived and employed to study the effects of initial and distributed mismatch on high-current beams. The basic concepts of the particle-core model, envelope modes, parametric resonances, the free-energy approach, and the idea of core-core resonances are introduced and extended to study beams in realistic linac lattices. The approach taken is to study the behavior of beams not only in simplified theoretical focusing structures but to highlight the beam dynamics in realistic accelerators. All effects which are described and derived with simplified analytic models, are tested in realistic lattices and are thus related to observable effects in linear accelerators. This approach involves the use of high-performance particle tracking codes, which are needed to simulate the behavior of the outermost particles in distributions of up to 100 million macro particles. In the end a set of design rules are established and their impact on the design of a typical high-intensity machine, the CERN SPL, is shown. The examples given in this document refer to two different design evolutions of the SPL study: the first conceptual design report (SPL I) and the second conceptual design report (SPL II). (orig.)

  13. MO-F-CAMPUS-T-04: Implementation of a Standardized Monthly Quality Check for Linac Output Management in a Large Multi-Site Clinic

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H; Yi, B; Prado, K [Univ. of Maryland School Of Medicine, Baltimore, MD (United States)

    2015-06-15

    Purpose: This work is to investigate the feasibility of a standardized monthly quality check (QC) of LINAC output determination in a multi-site, multi-LINAC institution. The QC was developed to determine individual LINAC output using the same optimized measurement setup and a constant calibration factor for all machines across the institution. Methods: The QA data over 4 years of 7 Varian machines over four sites, were analyzed. The monthly output constancy checks were performed using a fixed source-to-chamber-distance (SCD), with no couch position adjustment throughout the measurement cycle for all the photon energies: 6 and 18MV, and electron energies: 6, 9, 12, 16 and 20 MeV. The constant monthly output calibration factor (Nconst) was determined by averaging the machines’ output data, acquired with the same monthly ion chamber. If a different monthly ion chamber was used, Nconst was then re-normalized to consider its different NDW,Co-60. Here, the possible changes of Nconst over 4 years have been tracked, and the precision of output results based on this standardized monthly QA program relative to the TG-51 calibration for each machine was calculated. Any outlier of the group was investigated. Results: The possible changes of Nconst varied between 0–0.9% over 4 years. The normalization of absorbed-dose-to-water calibration factors corrects for up to 3.3% variations of different monthly QA chambers. The LINAC output precision based on this standardized monthly QC relative to the TG-51 output calibration is within 1% for 6MV photon energy and 2% for 18MV and all the electron energies. A human error in one TG-51 report was found through a close scrutiny of outlier data. Conclusion: This standardized QC allows for a reasonably simplified, precise and robust monthly LINAC output constancy check, with the increased sensitivity needed to detect possible human errors and machine problems.

  14. Development of a split coaxial RFQ for the JHP heavy ion linac

    International Nuclear Information System (INIS)

    Arai, Shigeaki.

    1990-05-01

    A split coaxial RFQ (SCRFQ) is being developed as the front-end structure of the heavy-ion linac chain planned in the Japanese Hadron Project (JHP). The features of the INS SCRFQ is that four modulated vanes are installed and that the whole cavity comprises short module cavities. The fundamental problems concerning to the rf and mechanical characteristics were clarified and solved through studies with a cold model. This model was then converted to an accelerating model working at 50 MHz. Acceleration tests using a proton beam showed that the linac had the designed performance. A 25.5-MHz prototype for a JHP machine is now under development. The cavity, 2.1 m in length and 0.9 m in diameter, has been built, and will accelerate ions with a charge-to-mass ratio greater than 1/30 from 1 keV/u to 45 keV/u. From low-power tests so far conducted, we have found that the cavity has good rf characteristics. (author)

  15. Start-To-End Simulations of the Energy Recovery Linac Prototype FEL

    CERN Document Server

    Gerth, Christopher; Muratori, Bruno; Owen, Hywel; Thompson, Neil R

    2004-01-01

    Daresbury Laboratory is currently building an Energy Recovery Linac Prototype (ERLP) that serves as a testbed for the study of beam dynamics and accelerator technology important for the design and construction of the proposed 4th Generation Light Source (4GLS) project. Two major objectives for the ERLP are the operation of an oscillator infra-red FEL and demonstration of energy recovery from an electron bunch with an energy spread induced by the FEL. In this paper we present start-to-end simulations including the FEL of the ERLP. The beam dynamics in the high-brightness injector, which consists of a DC photocathode gun and a super-conducting booster, have been modelled using the particle tracking code ASTRA. After the main linac, in which the particles are accelerated to 35 MeV, particles have been tracked with the code ELEGANT. The 3D code GENESIS was used to model the FEL interaction with the electron beam. Different modes of operation and their impact on the design of the ERLP are discussed.

  16. Conceptual Design of the Superconducting Proton Linac Short Cryo-module

    CERN Document Server

    Bourcey, N; Capatina, O; Azevedo, P; Montesinos, E; Parma, V; Renaglia, T; Vande Craen, A; Williams, L R; Weingarten, W; Rousselot, S; Duthil, P; Duchesne, P; Reynet, D; Dambre, P

    2012-01-01

    The Superconducting Proton Linac (SPL) is an R&amp;amp;D effort conducted by CERN in partnership with other international laboratories, aimed at developing key technologies for the construction of a multi-megawatt proton linac based on state-of-the-art Superconducting Radio Frequency technology, which would serve as a driver for new physics facilities such as neutrinos and radioactive ion beams. Amongst the main objectives of this effort, are the development of 704 MHz bulk niobium b=1 elliptical cavities, operating at 2 K and providing an accelerating field of 25 MV/m, and testing of a string of cavities integrated in a machine-type cryo-module. In an initial phase only four out of the eight cavities of an SPL cryo-module will be tested in a ½ length cryo-module developed for this purpose, and therefore called the Short Cryo-module. This paper presents the conceptual design of the SC, highlighting its innovative principles in terms of cavity supporting and alignment, and describes the integratio...

  17. Gas Injection And Fast Pressure-Rise Measurements For The Linac4 H− Source

    CERN Document Server

    Mahner, E; Lettry, J; Mattei, S; O'Neil, M; Neupert, H; Pasquino, C; Schmitzer, C

    2013-01-01

    In the era of the Large Hadron Collider, the CERN injector complex comprising the 34 years old Linac2 with its primary proton source, is presently upgraded with a new linear accelerator for H− (Linac4). The design, construction, and test of volume production and cesiated RF-driven H− ion sources is presently ongoing with the final goal of producing an H− beam with 80 mA beam current, 45 keV beam energy, 500 s pulse length, and a repetition rate of 2 Hz. In order to have quantitative information of the hydrogen gas density at the moment of plasma ignition the dynamic vacuum properties of the plasma generator were studied experimentally. We describe the experimental setup and present fast pressure-rise measurements for different parameters of the gas injection system, such as gas species (H2, He, N2, Ar), piezo valve voltage pulse length (200 - 500 s), and injection pressure (400 - 2800 mbar). The obtained data are compared with a conductance model of the plasma generator.

  18. A low emittance and uniform density Cs+ source for heavy ion induction linacs

    International Nuclear Information System (INIS)

    Henestroza, E.; Eylon, S.

    1990-01-01

    A heavy-ion induction linac experiment (MBE-4) in progress at LBL is studying the transport and acceleration of space-charge-dominated beams in a long alternate gradient focusing channel. Recent studies of the transverse beam dynamics suggested that characteristics of the injector geometry were contributing to the normalized transverse emittance growth. Phase space and current density distribution measurements of the beam extracted from the injector revealed aberrations and a hollow density profile. Based on EGUN calculations the authors redesigned the 10 mA injector for MBE-4 by modifying the cathode: Pierce electrode and using a curved emitting surface. The simulation predicts an extracted beam with less aberrations and a flat density profile. A test stand was used to check the new design. The density profile has measured and found to be in agreement with the numerical simulation

  19. Transport and energy selection of laser generated protons for postacceleration with a compact linac

    Science.gov (United States)

    Sinigardi, Stefano; Turchetti, Giorgio; Londrillo, Pasquale; Rossi, Francesco; Giove, Dario; De Martinis, Carlo; Sumini, Marco

    2013-03-01

    Laser accelerated proton beams have a considerable potential for various applications including oncological therapy. However, the most consolidated target normal sheath acceleration regime based on irradiation of solid targets provides an exponential energy spectrum with a significant divergence. The low count number at the cutoff energy seriously limits at present its possible use. One realistic scenario for the near future is offered by hybrid schemes. The use of transport lines for collimation and energy selection has been considered. We present here a scheme based on a high field pulsed solenoid and collimators which allows one to select a beam suitable for injection at 30 MeV into a compact linac in order to double its energy while preserving a significant intensity. The results are based on a fully 3D simulation starting from laser acceleration.

  20. Transport and energy selection of laser generated protons for postacceleration with a compact linac

    Directory of Open Access Journals (Sweden)

    Stefano Sinigardi

    2013-03-01

    Full Text Available Laser accelerated proton beams have a considerable potential for various applications including oncological therapy. However, the most consolidated target normal sheath acceleration regime based on irradiation of solid targets provides an exponential energy spectrum with a significant divergence. The low count number at the cutoff energy seriously limits at present its possible use. One realistic scenario for the near future is offered by hybrid schemes. The use of transport lines for collimation and energy selection has been considered. We present here a scheme based on a high field pulsed solenoid and collimators which allows one to select a beam suitable for injection at 30 MeV into a compact linac in order to double its energy while preserving a significant intensity. The results are based on a fully 3D simulation starting from laser acceleration.

  1. Clarifying Normalization

    Science.gov (United States)

    Carpenter, Donald A.

    2008-01-01

    Confusion exists among database textbooks as to the goal of normalization as well as to which normal form a designer should aspire. This article discusses such discrepancies with the intention of simplifying normalization for both teacher and student. This author's industry and classroom experiences indicate such simplification yields quicker…

  2. Applications of electron linacs to ADS: one potential path forward

    International Nuclear Information System (INIS)

    Wells, D.P.; Harmon, J.F.

    2011-01-01

    The application of electron linac accelerators to ADS systems offers a number of advantages for ADS applications. We propose a path forward with electron linac-driven ADS that takes advantage of those important ADS applications that are most easily achieved at relatively low cost, and then building on those successes to enable the more difficult applications with larger impact. We argue that the applications that are most easily achieved are medical isotope production, materials irradiation and environmental applications. The accelerator and target demands for each of these applications are essentially the same as for the ADS needs in energy production and the transmutation of waste. The successful demonstration of these important and highly-visible applications will, in turn, lead to greater visibility and funding to further major advances of ADS systems in energy production, nuclear waste transmutation, and applications to the thorium fuel cycle. (author)

  3. Investigation of alternating-phase focusing for superconducting linacs

    International Nuclear Information System (INIS)

    Sagalovsky, L.; Delayen, J.R.

    1992-01-01

    The paper describes a new model of alternating-phase focusing (APF) dynamics applicable to ion linacs with short independently controlled superconducting cavities. The equations of motion are derived for a cylindrically symmetric electric field represented by a traveling wave with continuous periodic phase modulation. Solutions are obtained and analyzed for both the linear and nonlinear particle motion. Problems of linear stability and overall longitudinal acceptance are solved using standard mathematical techniques for periodic systems; analytical results are obtained. It is shown that the main beam dynamical aspects of APF are adequately described by four parameters; equilibrium synchronous phase, phase modulation amplitude, length of APF period, and incremental energy gain. The model can be applied to study the feasibility of realizing APF in a low-β section of a proton linac. (author). 9 refs., 3 figs

  4. Energy spread in SLC linac with Landau damping

    International Nuclear Information System (INIS)

    Seeman, J.

    1984-01-01

    The possibility of using Landau damping to reduce the growth of the beam size due to transverse wake fields has been known for some time. Recently K. Bane has calculated the effects of Landau damping for the SLC. The energy spread is then slowly removed so that at the end of the linac it has returned to the SLC specification of less than +0.5%. The purpose of the energy spread is to reduce the resonant driving of the tail of the bunch by the head. In this note the expected energy spreads within the beam are tabulated at various positions along the linac for use by those people designing momentum dependent equipment and for those interested in Landau damping

  5. Design of a Marx-Topology Modulator for FNAL Linac

    Energy Technology Data Exchange (ETDEWEB)

    Butler, T. A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Garcia, F. G. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kufer, M. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Pfeffer, H. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Wolff, D. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-04-28

    The Fermilab Proton Improvement Plan (PIP) was formed in late 2011 to address important and necessary upgrades to the Proton Source machines (Injector line, Linac and Booster). The goal is to increase the proton flux by doubling the Booster beam cycle rate while maintaining the same intensity per cycle, the same uptime, and the same residual activation in the enclosure. For the Linac, the main focus within PIP is to address reliability. One of the main tasks is to replace the present hard-tube modulator used on the 200 MHz RF system. Plans to replace this high power system with a Marx-topology modulator, capable of providing the required waveform shaping to stabilize the accelerating gradient and compensate for beam loading, will be presented, along with development data from the prototype unit.

  6. Development of RF System Model for CERN Linac2 Tanks

    CERN Document Server

    Joshi, G; Vretenar, M; Kumar, G; Agarwal, V

    2010-01-01

    An RF system model has been created for the CERN Linac2 Tanks. RF systems in this linac have both single and double feed architectures. The main elements of these systems are: RF power amplifier, main resonator, feed-line and the amplitude and phase feedback loops. The model of the composite system is derived by suitably concatenating the models of these individual sub-systems. For computational efficiency the modeling has been carried out in the base band. The signals are expressed in in-phase - quadrature domain, where the response of the resonator is expressed using two linear differential equations, making it valid for large signal conditions. MATLAB/SIMULINK has been used for creating the model. The model has been found useful in predicting the system behaviour, especially during the transients. In the paper we present the details of the model, highlighting the methodology, which could be easily extended to multiple feed RF systems.

  7. Design of injector section for SPring-8 linac

    International Nuclear Information System (INIS)

    Yoshikawa, Hiroshi; Nakamura, Naoki; Mizuno, Akihiko; Suzuki, Shinsuke; Hori, Toshihiko; Yanagida, Kenichi; Mashiko, Katsuo; Yokomizo, Hideaki

    1993-07-01

    In the SPring-8, we are planning to use positrons in order to increase the beam life time in the storage-ring. For the injector linac, though high current beam production to yield positrons is alternative with accurate low current beam production for commissioning, we designed the injector section to achieve both of the high current mode and the low current mode. In this paper, overview of some simulation codes for the design of electron accelerators are described and the calculation results by TRACE for the injector section of the linac are shown. That is useful not only for the design of machines but for the selection of sensitive parameters to establish the good beam quality. Now the injector section, which is settled at Tokai Establishment, is arranged for the case of the performance check of the electron gun. And we present that the layout of this section is needed to be rearranged for the high current mode operation. (author)

  8. Beam forming system modernization at the MMF linac proton injector

    CERN Document Server

    Derbilov, V I; Nikulin, E S; Frolov, O T

    2001-01-01

    The isolation improvements of the beam forming system (BFS) of the MMF linac proton injector ion source are reported. The mean beam current and,accordingly, BFS electrode heating were increased when the MMF linac has began to operate regularly in long beam sessions with 50 Hz pulse repetition rate. That is why the BFS electrode high-voltage isolation that was made previously as two consequently and rigidly glued solid cylinder insulators has lost mechanical and electric durability. The substitution of large (160 mm) diameter cylinder insulator for four small diameter (20 mm) tubular rods has improved vacuum conditions in the space of beam forming and has allowed to operate without failures when beam currents being up to 250 mA and extraction and focusing voltage being up to 25 and 40 kV respectively. Moreover,the construction provides the opportunity of electrode axial move. The insulators are free from electrode thermal expansion mechanical efforts in a transverse direction.

  9. Leak Propagation Dynamics for the HIE-ISOLDE Superconducting Linac

    CERN Document Server

    Ady, M; Kersevan, R; Vandoni, G; Ziemianski, D

    2014-01-01

    In order to cope with space limitations of existing infrastructure, the cryomodules of the HIE-ISOLDE superconducting linac feature a common insulation and beam vacuum, imposing the severe cleanliness standard of RF cavities to the whole cryostat. Protection of the linac vacuum against air-inrush from the three experimental stations through the HEBT (High Energy Beam Transport) lines relies on fast valves, triggered by fast cold cathode gauges. To evaluate the leak propagation velocity as a function of leak size and geometry of the lines, a computational and experimental investigation is being carried out at CERN. A 28 m long tube is equipped with cold-cathode gauges. A leak is opened by the effect of a cutting pendulum, equipped with an accelerometer for data acquisition triggering, on a thin aluminium window. The air inrush dynamics is simulated by Finite Elements fluid dynamics in the viscous regime.

  10. Control system for 10 MeV irradiation electron linac

    International Nuclear Information System (INIS)

    Zeng Ziqiang; Zhang Lifeng; Lu Weixing; Gao Zhenjiang; Zhang Yan; Han Guangwen; Wang Shuxian

    2005-01-01

    Control system of the 10 MeV electron linac using Distributed Control System (DCS) was studied. The hardware of control system consists of four SIEMENS PLCs and monitor computer, the software bases on STEP 7, Labwindows/CVI and SQL Server. The bus between the monitor computer and the main PLC is 100 M industrial networks, between PLCs is MPI bus, between PLC and remote partner is PROFIBUS, between PLC and terminals is RS485/422. The software of control system can provide a friendly human machine interface to operate the machine, protect the human and equipment from risk, and storage the status of the accelerator real time to the database. The monitor and maintenance of the linac can been carried out not only on local computer or local network, but also in internet. (author)

  11. Plants for H- acceleration in the AGS Linac

    International Nuclear Information System (INIS)

    Barton, D.S.; Witkover, R.L.

    1979-01-01

    Since its commissioning in 1970, the 200 MeV Linac at the Brookhaven AGS has been capable of producing peak proton beam current of greater than 100 mA with pulse lengths up to 300 μsec at a repetition rate of 10 pulses/second. The linac typically runs at 5 pulses per second, providing a 60 mA pulse of 120 μsec duration every 1.6 to 2.4 seconds for conventional multiturn injection into the AGS. The intervening pulses of length up to 300 μsec are used by the radio-isotope production, chemistry and medical facilities. Preparations are now being made to inject and accelerate H - ions in order to implement charge exchange injection into the AGS. This paper describes the aspects of this work leading to an H - beam at 200 MeV

  12. Important aspects of linac beams for food irradiation

    International Nuclear Information System (INIS)

    McKeown, J.; Jones, R.T.

    1987-01-01

    Linac based irradiators will require careful design before they can be routinely adopted for the radiation processing of food. The transverse emittance and energy spread from simple injectors provide a significant challenge to the design of a beam delivery system which must handle high power especially in photon mode. Any nonuniform current distribution at the plane of the product is further complicated by large dose variations near the air/product interface, even with simple geometries. The paper describes the use of methods developed at AECL to control and monitor linac behaviour as well as electron interactions at the product surface. It also reports on activation cross-section measurements and particularly on neutron yields from composite targets, designed to monitor the energy of accelerators used in food applications. (orig.)

  13. A development of BPM for P-LINAC at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Almalki, Mohammed; Kester, Oliver; Forck, Peter; Kaufmann, Wolfgang; Sieber, Thomas; Kowina, Piotr; Vinzenz, Wolfgang; Krueger, Christoph [GSI, Darmstadt (Germany); Simon, Claire [CEA/DSM/IRFU (France); Tinta, Dejan; Hrovatin, Rok; Lemut, Promoz [Instrumentation Technologies, Solkan (Slovenia)

    2014-07-01

    Four-fold button Beam Position Monitor (BPM) has been developed for the planned Proton LINAC at the FAIR facility. These monitors will be installed at 14 locations along the LINAC and four of them will be mounted only about 40 mm upstream of the CH cavities. A BPM prototype will be fabricated to evaluate the rf power at the BPM location as generated by cavity excitation as well as to test different options in the mechanical design. For the read-out electronics, the I/Q digital signal processing will be implemented to derive the transverse beam position and the beam phase. This contribution presents the status of the BPM development and focuses on the mechanical design and the optimization of the button pick-ups. The development progress of digital signal processing system is discussed as well.

  14. The split coaxial linac structure and its RF modes

    International Nuclear Information System (INIS)

    Mueller, R.W.

    1989-01-01

    The Split Coaxial Cavity structure has been invented and applied for the first time in the heavy-ion RFQ linac MAXILAC of GSI. It has an ideally flat RF voltage distribution and a good power economy. From another standpoint, it is a member of the small family of linac structures where the two modes, the wanted one and the unflatness mode, are clearly and strictly separable. The unflatness or ''Q Line'' mode is analyzed in more detail in this paper. It is necessary for the understanding of the interaction of the beam with the cavity, possible beam instabilities resulting from it, and for curing these instabilities with the chance of obtaining improved beams. (orig.)

  15. Conversion of the AGS linac to H- acceleration

    International Nuclear Information System (INIS)

    Witkover, R.L.; Barton, D.S.; Reece, R.K.

    1983-01-01

    The AGS 200 MeV linac was converted to an H - accelerator during the summer of 1982 using a magnetron-type source in the column of the second pre-injector pit. Because of the re-entrant electrode design, a 20 keV transport line was required to carry the beam to the first electrode. Several changes were made to the source which enhanced its performance over previous designs. The same H - beam current is available at 2.75 times the duty factor with reduced deterioration of its output over several months of operation. The source, 750 keV transport, and linac modifications and performance will be presented

  16. The application of statistical process control in linac quality assurance

    International Nuclear Information System (INIS)

    Li Dingyu; Dai Jianrong

    2009-01-01

    Objective: To improving linac quality assurance (QA) program with statistical process control (SPC) method. Methods: SPC is applied to set the control limit of QA data, draw charts and differentiate the random and systematic errors. A SPC quality assurance software named QA M ANAGER has been developed by VB programming for clinical use. Two clinical cases are analyzed with SPC to study daily output QA of a 6MV photon beam. Results: In the clinical case, the SPC is able to identify the systematic errors. Conclusion: The SPC application may be assistant to detect systematic errors in linac quality assurance thus it alarms the abnormal trend to eliminate the systematic errors and improves quality control. (authors)

  17. Detuning effect in a traveling wave type linac

    International Nuclear Information System (INIS)

    Arai, S.; Kobayashi, K.; Tojyo, E.; Yoshida, K.

    1979-01-01

    A 15-MeV traveling wave type electron linac is used as the injector for the 1.3-GeV electron synchrotron at the Institute for Nuclear Study, University of Tokyo. The resonant frequency of this accelerator waveguide is 2758.00 MHz at 30 0 C. The performance of the linac,however, is improved when it is operated with a frequency which is higher than the design value by 200 to 400 KHz. It is shown that the detuning due to the beam loading is serious in such an accelerator waveguide in which the buncher and regular sections are combined, and the detuning effect can approximately be compensated by changing the operating frequency. The detuning effect in the traveling wave-type accelerator waveguide was studied both from experimental and theoretical aspects by using a short test waveguide

  18. Neutron H*(10) estimation and measurements around 18MV linac.

    Science.gov (United States)

    Cerón Ramírez, Pablo Víctor; Díaz Góngora, José Antonio Irán; Paredes Gutiérrez, Lydia Concepción; Rivera Montalvo, Teodoro; Vega Carrillo, Héctor René

    2016-11-01

    Thermoluminescent dosimetry, analytical techniques and Monte Carlo calculations were used to estimate the dose of neutron radiation in a treatment room with a linear electron accelerator of 18MV. Measurements were carried out through neutron ambient dose monitors which include pairs of thermoluminescent dosimeters TLD 600 ( 6 LiF: Mg, Ti) and TLD 700 ( 7 LiF: Mg, Ti), which were placed inside a paraffin spheres. The measurements has allowed to use NCRP 151 equations, these expressions are useful to find relevant dosimetric quantities. In addition, photoneutrons produced by linac head were calculated through MCNPX code taking into account the geometry and composition of the linac head principal parts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Spectral fluence of neutrons generated by radiotherapeutic Linacs

    International Nuclear Information System (INIS)

    Kralik, Miloslav; Solc, Jaroslav; Smoldasova, Jana; Vondracek, Vladimir; Farkasova, Estera; Ticha, Ivana

    2015-01-01

    Spectral fluences of neutrons generated in the heads of the radiotherapeutic linacs Varian Clinac 2100 C/D and Siemens ARTISTE were measured by means of the Bonner spheres spectrometer whose active detector of thermal neutrons was replaced by an activation detector, i.e. a tablet made of pure manganese. Measurements with different collimator settings reveal an interesting dependence of neutron fluence on the area defined by the collimator jaws. The determined neutron spectral fluences were used to derive ambient dose equivalent rate along the treatment coach. To clarify at which components of the linac neutrons are mainly created, the measurements were complemented with MCNPX calculations based on a realistic model of the Varian Clinac. (authors)

  20. Minimizing Energy Spread In The REX/HIE-ISOLDE Linac

    CERN Document Server

    Yucemoz, Mert

    2017-01-01

    This report tries to minimize the energy spread of the beam at the end of the REX-HIE-ISOLDE Linac using the last RF cavity as a buncher. Beams with very low energy spread are often required by the users of the facility In addition, one of the main reason to have minimum energy spread in longitudinal phase space is that higher beam energy spread translates in to a position spread after interacting with target. This causes an overlap in the position of different particles that makes it difficult to distinguish them. Hence, in order to find the operation settings for minimum energy spread at the end of the REX-HIE-ISOLDE linac and to inspect the ongoing physics, several functions on Matlab were created that runs beam dynamics program called “TRACKV39” that provides some graphs and values as a result for analysis.