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Sample records for modeling beam lines

  1. Secondary beam line phase space measurement and modeling at LAMPF

    International Nuclear Information System (INIS)

    Floyd, R.; Harrison, J.; Macek, R.; Sanders, G.

    1979-01-01

    Hardware and software have been developed for precision on-line measurement and fitting of secondary beam line phase space parameters. A system consisting of three MWPC planes for measuring particle trajectories, in coincidence with a time-of-flight telescope and a range telescope for particle identification, has been interfaced to a computer. Software has been developed for on-line track reconstruction, application of experimental cuts, and fitting of two-dimensional phase space ellipses for each particle species. The measured distributions have been found to agree well with the predictions of the Monte Carlo program DECAY TURTLE. The fitted phase space ellipses are a useful input to optimization routines, such as TRANSPORT, used to search for superior tunes. Application of this system to the LAMPF Stopped Muon Channel is described

  2. SLC beam line error analysis using a model-based expert system

    International Nuclear Information System (INIS)

    Lee, M.; Kleban, S.

    1988-02-01

    Commissioning particle beam line is usually a very time-consuming and labor-intensive task for accelerator physicists. To aid in commissioning, we developed a model-based expert system that identifies error-free regions, as well as localizing beam line errors. This paper will give examples of the use of our system for the SLC commissioning. 8 refs., 5 figs

  3. Evolution of a beam dynamics model for the transport line in a proton therapy facility

    Science.gov (United States)

    Rizzoglio, V.; Adelmann, A.; Baumgarten, C.; Frey, M.; Gerbershagen, A.; Meer, D.; Schippers, J. M.

    2017-12-01

    During the conceptual design of an accelerator or beamline, first-order beam dynamics models are essential for studying beam properties. However, they can only produce approximate results. During commissioning, these approximate results are compared to measurements, which will rarely coincide if the model does not include the relevant physics. It is therefore essential that this linear model is extended to include higher-order effects. In this paper, the effects of particle-matter interaction have been included in the model of the transport lines in the proton therapy facility at the Paul Scherrer Institut (PSI) in Switzerland. The first-order models of these beamlines provide an approximated estimation of beam size, energy loss and transmission. To improve the performance of the facility, a more precise model was required and has been developed with opal (Object Oriented Parallel Accelerator Library), a multiparticle open source beam dynamics code. In opal, the Monte Carlo simulations of Coulomb scattering and energy loss are performed seamless with the particle tracking. Beside the linear optics, the influence of the passive elements (e.g., degrader, collimators, scattering foils, and air gaps) on the beam emittance and energy spread can be analyzed in the new model. This allows for a significantly improved precision in the prediction of beam transmission and beam properties. The accuracy of the opal model has been confirmed by numerous measurements.

  4. The Fluka Linebuilder and Element Database: Tools for Building Complex Models of Accelerators Beam Lines

    CERN Document Server

    Mereghetti, A; Cerutti, F; Versaci, R; Vlachoudis, V

    2012-01-01

    Extended FLUKA models of accelerator beam lines can be extremely complex: heavy to manipulate, poorly versatile and prone to mismatched positioning. We developed a framework capable of creating the FLUKA model of an arbitrary portion of a given accelerator, starting from the optics configuration and a few other information provided by the user. The framework includes a builder (LineBuilder), an element database and a series of configuration and analysis scripts. The LineBuilder is a Python program aimed at dynamically assembling complex FLUKA models of accelerator beam lines: positions, magnetic fields and scorings are automatically set up, and geometry details such as apertures of collimators, tilting and misalignment of elements, beam pipes and tunnel geometries can be entered at user’s will. The element database (FEDB) is a collection of detailed FLUKA geometry models of machine elements. This framework has been widely used for recent LHC and SPS beam-machine interaction studies at CERN, and led to a dra...

  5. Transfer line scattering model of therapeutic hadron beams and applications to nozzle and gantry optimization

    Directory of Open Access Journals (Sweden)

    M. Palm

    2013-01-01

    Full Text Available The field of hadron therapy is growing rapidly with several facilities currently being planned, under construction or in commissioning worldwide. In the “active scanning” irradiation technique, the target is irradiated using a narrow pencil beam that is scanned transversally over the target while the penetration depth is altered with the beam energy. Together, the target dose can thereby be conformed in all three dimensions to the shape of the tumor. For applications where a sharp lateral beam penumbra is required in order to spare critical organs from unwanted dose, beam size blowup due to scattering in on-line beam diagnostic monitors, air gaps and passive elements like the ripple filter must be minimized. This paper presents a model for transverse scattering of therapeutic hadron beams along arbitrary multislab geometries. The conventional scattering formulation, which is only applicable to a drift space, is extended to not only take beam optics into account, but also non-Gaussian transverse beam profiles which are typically obtained from the slow resonant extraction from a synchrotron. This work has been carried out during the design phase of the beam delivery system for MedAustron, an Austrian hadron therapy facility with first patient treatment planned for the end of 2015. Irradiation will be performed using active scanning with proton and carbon ion beams. As a direct application of the scattering model, design choices for the MedAustron proton gantry and treatment nozzles are evaluated with respect to the transverse beam profile at the focal point; in air and at the Bragg peak.

  6. Semi-empirical model for fluorescence lines evaluation in diagnostic x-ray beams.

    Science.gov (United States)

    Bontempi, Marco; Andreani, Lucia; Labanti, Claudio; Costa, Paulo Roberto; Rossi, Pier Luca; Baldazzi, Giuseppe

    2016-01-01

    Diagnostic x-ray beams are composed of bremsstrahlung and discrete fluorescence lines. The aim of this study is the development of an efficient model for the evaluation of the fluorescence lines. The most important electron ionization models are analyzed and implemented. The model results were compared with experimental data and with other independent spectra presented in the literature. The implemented peak models allow the discrimination between direct and indirect radiation emitted from tungsten anodes. The comparison with the independent literature spectra indicated a good agreement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Modeling the biophysical effects in a carbon beam delivery line by using Monte Carlo simulations

    Science.gov (United States)

    Cho, Ilsung; Yoo, SeungHoon; Cho, Sungho; Kim, Eun Ho; Song, Yongkeun; Shin, Jae-ik; Jung, Won-Gyun

    2016-09-01

    The Relative biological effectiveness (RBE) plays an important role in designing a uniform dose response for ion-beam therapy. In this study, the biological effectiveness of a carbon-ion beam delivery system was investigated using Monte Carlo simulations. A carbon-ion beam delivery line was designed for the Korea Heavy Ion Medical Accelerator (KHIMA) project. The GEANT4 simulation tool kit was used to simulate carbon-ion beam transport into media. An incident energy carbon-ion beam with energy in the range between 220 MeV/u and 290 MeV/u was chosen to generate secondary particles. The microdosimetric-kinetic (MK) model was applied to describe the RBE of 10% survival in human salivary-gland (HSG) cells. The RBE weighted dose was estimated as a function of the penetration depth in the water phantom along the incident beam's direction. A biologically photon-equivalent Spread Out Bragg Peak (SOBP) was designed using the RBE-weighted absorbed dose. Finally, the RBE of mixed beams was predicted as a function of the depth in the water phantom.

  8. Status of ACCULINNA beam line

    CERN Document Server

    Rodin, A M; Bogdanov, D D; Golovkov, M S; Fomichev, A S; Sidorchuk, S I; Slepnev, R S; Wolski, R; Ter-Akopian, G M; Oganessian, Yu T; Yukhimchuk, A A; Perevozchikov, V V; Vinogradov, Yu I; Grishenchkin, S K; Demin, A M; Zlatoustovskii, S V; Kuryakin, A V; Filchagin, S V; Ilkaev, R I

    2003-01-01

    The separator ACCULINNA was upgraded to achieve new experimental requirements. The beam line was extended by new ion-optical elements beyond the cyclotron hall. The new arrangements yield much better background conditions. The intensities of sup 6 He and sup 8 He radioactive beams produced in fragmentation of 35 A MeV sup 1 sup 1 B ions were increased up to a factor of 10. The upgraded beam line was used in experiments to study the sup 5 H resonance states populated in the t+t reaction. A cryogenic liquid tritium target was designed and installed at the separator beam line.

  9. Beam line design using G4BeamLine

    CERN Document Server

    Dogan, Arda

    2014-01-01

    In Turkey in Ankara TAEK SANAEM Proton Accelerator Facility (PAF), there is a cyclotron which produces a focused intense 30 MeV proton beam and sends this beam to four different arms, three of which uses this beam to produce pharmaceutical medicine. The remaining one is spared for R&D purposes and the idea was to use these protons coming out from the fourth arm to use space radiation tests, which cannot be done in Turkey at the moment. However, according to SCC 25100 standards which is for 30 MeV protons, the beam coming out of cyclotron is too intense and focused to use for space radiation tests. Therefore, the main aim of my project is to design a beam line which will defocus the beam and reduce the flux so that the space radiation tests can be done according to the standards of SCC 25100.

  10. Beam line windows at LAMPF

    International Nuclear Information System (INIS)

    Brown, R.D.; Grisham, D.L.; Lambert, J.E.

    1985-01-01

    The A-6 main beam-line window at LAMPF separates the vacuum of the main beam line from the isotope production station, proton irradiation ports, and the beam stop, which operate in air. This window must withstand the design beam current of 1 mA at 800 MeV for periods of at least 3000 hours without failure. The window is water cooled and must be strong enough to withstand the 2.1 MPa (300 psig) cooling water pressure, as well as beam-induced thermal stresses. Two designs have been used to meet these goals, a stepped-plate window and a hemispherical window, both made from a precipitation-hardened nickel base alloy, Alloy 718. Calculations of the temperatures and stresses in each of these windows are presented

  11. Standardization of beam line representations

    International Nuclear Information System (INIS)

    Carey, David C.

    1999-01-01

    Standardization of beam line representations means that a single set of data can be used in many situations to represent a beam line. This set of data should be the same no matter what the program to be run or the calculation to be made. We have concerned ourselves with three types of standardization: (1) The same set of data should be usable by different programs. (2) The inclusion of other items in the data, such as calculations to be done, units to be used, or preliminary specifications, should be in a notation similar to the lattice specification. (3) A single set of data should be used to represent a given beam line, no matter what is being modified or calculated. The specifics of what is to be modified or calculated can be edited into the data as part of the calculation. These three requirements all have aspects not previously discussed in a public forum. Implementations into TRANSPORT will be discussed

  12. Standardization of beam line representations

    International Nuclear Information System (INIS)

    Carey, David C.

    1998-01-01

    Standardization of beam line representations means that a single set of data can be used in many situations to represent a beam line. This set of data should be the same no matter what the program to be run or the calculation to be made. We have concerned ourselves with three types of standardization: (1) The same set of data should be usable by different programs. (2) The inclusion of other items in the data, such as calculations to be done, units to be used, or preliminary specifications, should be in a notation similar to the lattice specification. (3) A single set of data should be used to represent a given beam line, no matter what is being modified or calculated. The specifics of what is to be modified or calculated can be edited into the data as part of the calculation. These three requirements all have aspects not previously discussed in a public forum. Implementations into TRANSPORT will be discussed

  13. Doppler-shifted neutral beam line shape and beam transmission

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O`Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-{alpha} line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3{degrees} (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9{degrees}. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9{degrees}. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of {approximately}75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2{degrees}, rather than the 4.95{degrees} subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence.

  14. Doppler-shifted neutral beam line shape and beam transmission

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-α line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3 degrees (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9 degrees. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9 degrees. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of ∼75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2 degrees, rather than the 4.95 degrees subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence

  15. The appearance of beam lines

    International Nuclear Information System (INIS)

    Carey, D.C.

    1993-05-01

    The combination of an existing graphics package with a large program like TRANSPORT has often resulted in considerable modification to the large program. Use of other graphics package has resulted in essentially having to repeat the work. This difficulty has been avoided in a modification of TRANSPORT which produce layouts of beam lines. Drawings of the reference trajectory and three-dimensional images of all magnets are made by the graphics package TOP DRAWER. Nothing specific to TOP DRAWER or any other graphics has been incorporated into TRANSPORT. If a user is with a different graphics package he or she can then begin usage of this alternate package essentially immediately

  16. The appearance of beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Carey, D.C.

    1993-05-01

    The combination of an existing graphics package with a large program like TRANSPORT has often resulted in considerable modification to the large program. Use of other graphics package has resulted in essentially having to repeat the work. This difficulty has been avoided in a modification of TRANSPORT which produce layouts of beam lines. Drawings of the reference trajectory and three-dimensional images of all magnets are made by the graphics package TOP DRAWER. Nothing specific to TOP DRAWER or any other graphics has been incorporated into TRANSPORT. If a user is with a different graphics package he or she can then begin usage of this alternate package essentially immediately.

  17. The appearance of beam lines

    International Nuclear Information System (INIS)

    Carey, D.C.

    1993-01-01

    The combination of an existing graphics package with a large program like TRANSPORT has often resulted in considerable modification to the large program. Use of other graphics packages has resulted in essentially having to repeat the work. This difficulty has been avoided in a modification of TRANSPORT which produces layouts of beam lines. Drawings of the reference trajectory and three dimensional images of all magnets are made by the graphics package TOP DRAWER. Nothing specific to TOP DRAWER or any other graphics package has been incorporated into TRANSPORT. If a user is familiar with a different graphics package he or she can then begin usage of this alternate package essentially immediately

  18. Beam line to S155

    CERN Multimedia

    1977-01-01

    The experiment S155 was designed by the Orsay (CSNM-CNRS) Collaboration to observe the properties of exotic light nuclei. It was installed in the PS neutrino tunnel. The photo shows a mass spectrometer (in the background) on line with the PS proton beam which arrives (bottom, right) from the fast extraction FE74. Roger Fergeau stands on the left. The alkaline isotopes produced in the carbon-uranium target heated at 2000°C were swiftly extracted, mass separated, and brought to a detector behind the shielding. Sodium 34 (11 protons and 23 neutrons) was observed and its half-life of only 5 ms was measured. The excited levels 2+ of Magnesium 30 and Magnesium 32 (Sodium descendants) were localised, and the magic number 20 was found to vanish. Thus, the discovery made earlier for Sodium 30 and Sodium 32, with the same apparatus, was confirmed. (See also photo 7706511.)

  19. BEAM TRANSPORT LINES FOR THE BSNS.

    Energy Technology Data Exchange (ETDEWEB)

    WEI, J.

    2006-06-26

    This paper presents the design of two beam transport lines at the BSNS: one is the injection line from the Linac to the RCS and the other is the target line from the RCS to the target station. In the injection beam line, space charge effects, transverse halo collimation, momentum tail collimation and debunching are the main concerned topics. A new method of using triplet cells and stripping foils is used to collimate transverse halo. A long straight section is reserved for the future upgrading linac and debuncher. In the target beam line, large halo emittance, beam stability at the target due to kicker failures and beam jitters, shielding of back-scattering neutrons from the target are main concerned topics. Special bi-gap magnets will be used to reduce beam losses in the collimators in front of the target.

  20. A directly heated electron beam line source

    International Nuclear Information System (INIS)

    Iqbal, M.; Masood, K.; Rafiq, M.; Chaudhry, M.A.

    2002-05-01

    A 140-mm cathode length, Electron Beam Line Source with a high degree of focusing of the beam is constructed. The design principles and basic characteristic considerations for electron beam line source consists of parallel plate electrode geometric array as well as a beam power of 35kW are worked out. The dimensions of the beam at the work site are 1.25xl00mm. The gun is designed basically for the study of evaporation and deposition characteristic of refractory metals for laboratory use. However, it may be equally used for melting and casting of these metals. (author)

  1. FFAG Beam Line for nuPIL - Neutrinos from PIon Beam Line

    Energy Technology Data Exchange (ETDEWEB)

    Lagrange, Jean-Baptiste [Fermilab; Pasternak, Jaroslaw [Rutherford; Bross, Alan [Fermilab; Liu, Ao [Fermilab; Appleby, Robert [Cockcroft Inst. Accel. Sci. Tech.; Tygier, Sam [Cockcroft Inst. Accel. Sci. Tech.

    2016-06-01

    The Long Baseline Neutrino Facilities (LBNF) program aims to deliver a neutrino beam for the Deep Underground Neutrino Experiment (DUNE). The current baseline for LBNF is a conventional magnetic horn and decay pipe system. Neutrinos from PIon beam Line (nuPIL) is a part of the optimization effort to optimize the LBNF. It consists of a pion beam line after the horn to clean the beam of high energy protons and wrong-sign pions before transporting them into a decay beam line, where instrumentation could be implemented. This paper focuses on the FFAG solution for this pion beam line. The resulting neutrino flux is also presented.

  2. The IFUSP microtron accelerator beam transport line

    International Nuclear Information System (INIS)

    Rios, Paulo Beolchi

    2002-01-01

    In this work, the electron optical project of the IFUSP microtron beam transport line is presented, including the operational values for the parameters of the dipolar and quadrupolar electromagnets, as well as their location along the beam line. Analytical calculations and computer simulations were performed to obtain these results, and a programming tool was developed in order to analyze the beam parameters and to help studying racetrack microtrons. The electron optical simulations were split into two different study cases: the microtron booster, and the transfer line. In the first case, it was determined the main operational parameters of a microtron working far from its usual stability conditions. In the latter, it was done the basic design of the linking line between the booster and main (not yet built) microtrons, and between them and the experimental hall, with a total path length of approximately 32 m including large horizontal and vertical deflections with variable beam energy. (author)

  3. Beam line for Schools: beyond expectations

    CERN Multimedia

    Cian O'Luanaigh

    2014-01-01

    Out of 292 proposals for CERN's first ever "Beam line for Schools" contest, two teams of high-school students – Odysseus' Comrades from Varvakios Pilot School in Athens, Greece and Dominicuscollege from Dominicus College in Nijmegen in the Netherlands – were selected to spend 10 days conducting their proposed experiments at the fully equipped T9 beam line on CERN's Meyrin site. Dedicated CERN staff and users from across the departments have put in a huge effort to ensure the success of the project.   Detector physicist Cenk Yidriz (centre, white helmet) explains the setup of the "Beamline for schools" experiment at the T9 beamline. It's finally beam time. After months of organisation, coding, engineering and even painting the experimental area, the T9 beam line is ready to deliver protons to experiments devised and built by high-school students. “They are here to collect data and experience the l...

  4. Diode line scanner for beam diagnostics

    International Nuclear Information System (INIS)

    Gustov, S.A.

    1987-01-01

    The device-scanning diode line is described. It is applied for beam profile measuring with space precision better than ± 0.5 mm and with discreteness of 3 mm along Y-axis and 0.25 mm along X-axis. The device is easy in construction, reliable and has a small time of information acquisition (2-5 min). The working range is from 100 to 10 6 rad/min (10 6 -10 10 part/mm 2 /s for 660 MeV protons). Radioresistance is 10 7 rad. The device can be applied for precise beam line element tuning at beam transporting and emittance measuring. The fixed diode line (a simplified device version) has smaller dimensions and smaller time of data acquisition (2-5 s). It is applied for quick preliminary beamline tuning. The flowsheet and different variants of data representation on beam profile are given

  5. SU-E-T-794: Validation of the MCNPX Monte Carlo Model of the Ocular Beam Line at the Proton Therapy Center Houston

    Energy Technology Data Exchange (ETDEWEB)

    Titt, U; Suzuki, K [The Univ. of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: The PTCH is preparing the ocular proton beam nozzle for clinical use. Currently commissioning measurements are being performed using films, diodes and ionization chambers. In parallel, a Monte Carlo model of the beam line was created for integration into the automated Monte Carlo treatment plan computation system, MC{sup 2}. This work aims to compare Monte Carlo predictions to measured proton doses in order to validate the Monte Carlo model. Methods: A complete model of the double scattering ocular beam line has been created and is capable of simulating proton beams with a comprehensive set of beam modifying devices, including eleven different range modulator wheels. Simulations of doses in water were scored and compare to ion chamber measurements of depth doses, lateral dose profiles extracted from half beam block exposures of films, and diode measurements of lateral penumbrae at various depths. Results: All comparison resulted in an average relative entrance dose difference of less than 3% and peak dose difference of less than 2%. All range differences were smaller than 0.2 mm. The differences in the lateral beam profiles were smaller than 0.2 mm, and the differences in the penumbrae were all smaller than 0.4%. Conclusion: All available data shows excellent agreement of simulations and measurements. More measurements will have to be performed in order to completely and systematically validate the model. Besides simulating and measuring PDDs and lateral profiles of all remaining range modulator wheels, the absolute dosimetry factors in terms of number of source protons per monitor unit have to be determined.

  6. On a laser beam fiducial line application for metrological purposes

    International Nuclear Information System (INIS)

    Batusov, V.; Budagov, J.; Lyablin, M.; Rusakovich, N.; Sisakyan, A.; Topilin, N.; Khubua, J.; Lasseur, C.

    2008-01-01

    The possibility of a collimated one-mode laser beam used as a fiducial line is considered. The technology of an 'extended' laser beam formation and application for a much extended fiducial line is proposed

  7. Implementation of EPICS based Control System for Radioisotope Beam line

    International Nuclear Information System (INIS)

    Kim, Jae-Ha; Ahn, Tae-Sung; Song, Young-Gi; Kwon, Hyeok-Jung; Cho, Yong-Sub

    2015-01-01

    Korea Mult-purpose Accelerator Complex (KOMAC) has been operating 100 MeV proton linear accelerator . For operating 100 MeV linac, various control system has been implemented such as vacuum, power supply, RCCS and etc. KOMAC is operating two beam lines so that clients can use 100 MeV proton beam for their experiment. KOMAC sends beam to beam line and target room using two dipole magnets and several quadrupole magnets. As demand for experiments and Radius Isotope using beam is increased, another beam line is under construction and RI beam line control system is need. To synchronize with KOMAC control system, RI beam line control system is based on Experimental Physics and Industrial control System (EPICS) software. The beam is transported to RI beam line to control magnet power supply and vacuum. Implementation of RI beam line control system is presented and some preliminary results are reported. The base RI beam line control system is implemented. It can control beam direction and vacuum. Comparing archived data and current data, RI beam line and control system will be improved. In the future, scroll pump and gate control system will be implemented using programmable logic controller PLC. RI beam interlock sequence will be added to KOMAC interlock system to protect linac

  8. A beam source model for scanned proton beams.

    Science.gov (United States)

    Kimstrand, Peter; Traneus, Erik; Ahnesjö, Anders; Grusell, Erik; Glimelius, Bengt; Tilly, Nina

    2007-06-07

    A beam source model, i.e. a model for the initial phase space of the beam, for scanned proton beams has been developed. The beam source model is based on parameterized particle sources with characteristics found by fitting towards measured data per individual beam line. A specific aim for this beam source model is to make it applicable to the majority of the various proton beam systems currently available or under development, with the overall purpose to drive dose calculations in proton beam treatment planning. The proton beam phase space is characterized by an energy spectrum, radial and angular distributions and deflections for the non-modulated elementary pencil beam. The beam propagation through the scanning magnets is modelled by applying experimentally determined focal points for each scanning dimension. The radial and angular distribution parameters are deduced from measured two-dimensional fluence distributions of the elementary beam in air. The energy spectrum is extracted from a depth dose distribution for a fixed broad beam scan pattern measured in water. The impact of a multi-slab range shifter for energy modulation is calculated with an own Monte Carlo code taking multiple scattering, energy loss and straggling, non-elastic and elastic nuclear interactions in the slab assembly into account. Measurements for characterization and verification have been performed with the scanning proton beam system at The Svedberg Laboratory in Uppsala. Both in-air fluence patterns and dose points located in a water phantom were used. For verification, dose-in-water was calculated with the Monte Carlo code GEANT 3.21 instead of using a clinical dose engine with approximations of its own. For a set of four individual pencil beams, both with the full energy and range shifted, 96.5% (99.8%) of the tested dose points satisfied the 1%/1 mm (2%/2 mm) gamma criterion.

  9. BEAMS3D Neutral Beam Injection Model

    Energy Technology Data Exchange (ETDEWEB)

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  10. G4beamline Particle Tracking in Matter Dominated Beam Lines

    Energy Technology Data Exchange (ETDEWEB)

    T.J. Roberts, K.B. Beard, S. Ahmed, D. Huang, D.M. Kaplan

    2011-03-01

    The G4beamline program is a useful and steadily improving tool to quickly and easily model beam lines and experimental equipment without user programming. It has both graphical and command-line user interfaces. Unlike most accelerator physics codes, it easily handles a wide range of materials and fields, being particularly well suited for the study of muon and neutrino facilities. As it is based on the Geant4 toolkit, G4beamline includes most of what is known about the interactions of particles with matter. We are continuing the development of G4beamline to facilitate its use by a larger set of beam line and accelerator developers. A major new feature is the calculation of space-charge effects. G4beamline is open source and freely available at http://g4beamline.muonsinc.com

  11. MuSR Beam Line Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. W. [Weirich Consulting Services, Inc. Hunterville, NC (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2013-12-13

    When a substance is implanted with positive muons the precession of their magnetic moments can be used to sample the magnetic properties of the material. The information obtained is complementary to that from NMR, ESR, and neutron scattering. To date, only four user facilities exist in the world but none in the US. We explore the possibility of using the AGS complex at BNL for a μSR facility for the production of positive surface muons. With an incident proton intensity of 1014 protons per second hitting a 200 mm long 0.5 mm thick graphite target, our preliminary design of the beam line could produce low momentum surface muons (24–30 MeV/c) with a flux of 0.9 MHz/cm2 for experiments.

  12. BEAM LINE DESIGN FOR THE CERN HIRADMAT TEST FACILITY

    CERN Document Server

    Hessler, C; Goddard, B; Meddahi, M; Weterings, W

    2009-01-01

    The LHC phase II collimation project requires beam shock and impact tests of materials used for beam intercepting devices. Similar tests are also of great interest for other accelerator components such as beam entrance/exit windows and protection devices. For this purpose a dedicated High Radiation Material test facility (HiRadMat) is under study. This facility may be installed at CERN at the location of a former beam line. This paper describes the associated beam line which is foreseen to deliver a 450 GeV proton beam from the SPS with an intensity of up to 3×1013 protons per shot. Different beam line designs will be compared and the choice of the beam steering and diagnostic elements will be discussed, as well as operational issues.

  13. Beam Line Design for the CERN Hiradmat Test Facility

    CERN Document Server

    Hessler, C; Goddard, B; Meddahi, M; Weterings, W

    2010-01-01

    The LHC phase II collimation project requires beam shock and impact tests of materials used for beam intercepting devices. Similar tests are also of great interest for other accelerator components such as beam entrance/exit windows and protection devices. For this purpose a dedicated High Radiation Material test facility (HiRadMat) is under study. This facility may be installed at CERN at the location of a former beam line. This paper describes the associated beam line which is foreseen to deliver a 450 GeV proton beam from the SPS with an intensity of up to 3×10**13 protons per shot. Different beam line designs will be compared and the choice of the beam steering and diagnostic elements will be discussed, as well as operational issues.

  14. Magnet power supply and beam line control for a secondary beam line K6

    International Nuclear Information System (INIS)

    Suzuki, Y.; Takasaki, M.; Minakawa, M.; Ishii, H.; Kato, Y.; Ieiri, M.; Tanaka, K.H.; Noumi, H.; Yamanoi, Y.

    1992-01-01

    K6 is a secondary separated-beam line with momentum range up to 2.0 GeV/c in the north experimental hall at the KEK 12 GeV Proton Synchrotron (KEK-PS). On the construction, newly developed magnet power supplies (MPSs), in each of them a microprocessor is embedded, are introduced. The features of the MPS are as follows: 1, The MPS is connected to an upper-level beam line controller (BLC) by GPIB highway for exchanging simple messages. 2, All the operations of the MPS are supervised by the microprocessor, which has its individual parameters and fault messages. It reduces the load of the upper-level controller. 3, The MPS has functions to inspect itself and to report the result. It saves much time and labor of maintenance. (author)

  15. Progress during the decade of the BSF beam-line

    International Nuclear Information System (INIS)

    Irie, Yoshiro; Adachi, Toshikazu; Yano, Yoshiharu; Fujimori, Hiroshi; Kaneko, Naokatsu; Kobayashi, Yasuo; Tahara, Toshihiro.

    1991-07-01

    Since the Booster Synchrotron Utilization Facility (BSF) came into operation in June, 1980, ten years have passed. This report summarizes the development of beam-line hardware and software system during the decade. Especially, the result on radiation protection along the beam-line is satisfactory. (author)

  16. Simulation of a low energy beam transport line

    International Nuclear Information System (INIS)

    Yang Yao; Liu Zhanwen; Zhang Wenhui; Ma Hongyi; Zhang Xuezhen; Zhao Hongwei; Yao Ze'en

    2012-01-01

    A 2.45 GHz electron cyclotron resonance intense proton source and a low energy beam transport line with dual-Glaser lens were designed and fabricated by Institute of Modern Physics for a compact pulsed hadron source at Tsinghua. The intense proton beams extracted from the ion source are transported through the transport line to match the downstream radio frequency quadrupole accelerator. Particle-in-cell code BEAMPATH was used to carry out the beam transport simulations and optimize the magnetic field structures of the transport line. Emittance growth due to space charge and spherical aberrations of the Glaser lens were studied in both theory and simulation. The results show that narrow beam has smaller aberrations and better beam quality through the transport line. To better match the radio frequency quadrupole accelerator, a shorter transport line is desired with sufficient space charge neutralization. (authors)

  17. Muon Beam Studies in the H4 beam line and the Gamma Irradiation Facility (GIF++)

    CERN Document Server

    Margraf, Rachel; CERN. Geneva. EN Department

    2017-01-01

    In this report, I summarize my work of detailed study and optimization of the muon beam configuration of H4 beam line in SPS North Area. Using Monte-Carlo simulations, I studied the properties and behavior of the muon beam in combination with the field of the large, spectrometer “ GOLIATH” magnet at -1.5, -1.0, 0, 1.0 and 1.5 Tesla, which is shown to affect the central x position of the muon beam that is delivered to the Gamma Irradiation Facility (GIF++). I also studied the muon beam for different configurations of the two XTDV beam dumps upstream of GIF++ in the H4 beam line. I will also discuss my role in mapping the magnetic field of the GOLIATH magnet in the H4 beam line.

  18. Beam dynamics and error study of the medium energy beam transport line in the Korea Heavy-Ion Medical Accelerator

    Science.gov (United States)

    Kim, Chanmi; Kim, Eun-San; Hahn, Garam

    2016-11-01

    The Korea Heavy Ion Medical Accelerator consists of an injector and a synchrotron for an ion medical accelerator that is the first carbon-ion therapy system in Korea. The medium energy beam transport(MEBT) line connects the interdigital H-mode drift tube linac and the synchrotron. We investigated the beam conditions after the charge stripper by using the LISE++ and the SRIM codes. The beam was stripped from C4+ into C6+ by using the charge stripper. We investigated the performance of a de-buncher in optimizing the energy spread and the beam distribution in z-dW/W (direction of beam progress-beam and energy) phase. We obtained the results of the tracking simulation and the error analysis by using the TRACK code. Possible misalignments and rotations of the magnets were considered in the simulations. States of the beam were examined when errors occurred in the magnets by the applying analytic fringe field model in TRACK code. The condition for the beam orbit was optimized by using correctors and profile monitors to correct the orbit. In this paper, we focus on the beam dynamics and the error studies dedicated to the MEBT beam line and show the optimized beam parameters for the MEBT.

  19. Neutrinos from PIon Beam Line, nuPIL

    Energy Technology Data Exchange (ETDEWEB)

    Lagrange, J. B. [Imperial Coll., London; Pasternak, J. [Imperial Coll., London; Bross, A. [Fermilab; Liu, A. [Fermilab

    2016-05-05

    LBNF-DUNE (Long Baseline Neutrino Facilities - Deep Underground Neutrino Experiment) is a project based at Fermilab to study neutrino oscillations. The current baseline regarding the neutrino production considers the conventional approach: a high energy proton beam hits a target, producing pions that are collected by a horn and that decay in a decay pipe. An alternative solution, called nuPIL (neutrinos from a Pion beam Line) consists of using a beam line to guide the pions to clean the beam and to put instrumentation to monitor it. This paper presents the concept and the first preliminary results.

  20. Developing an expert system to control a beam line at the Los Alamos Meson Physics Facility

    International Nuclear Information System (INIS)

    Clearwater, S.H.; Papcun, G.; Clark, D.A.

    1985-01-01

    High energy particle experiments require an accelerator as a source of high energy particles. To increase the productivity of an accelerator facility, we wish to develop an expert system to control beam lines. Expert Systems are a branch of Artificial Intelligence where a computer program performs tasks requiring human expertise. Unlike most expert systems we have a physical model underlying our beam line and this model can be used with the expert system to improve performance. The development of the expert system will lead to an increased understanding of the beam line as well as the possibility of state-of-the-art expert system building

  1. On-line spectroscopy with thermal atomic beams

    International Nuclear Information System (INIS)

    Thibault, C.; Guimbal, P.; Klapisch, R.; Saint Simon, M. de; Serre, J.M.; Touchard, F.; Duong, H.T.; Jacquinot, P.; Juncar, P.

    1981-01-01

    On-line high resolution laser spectroscopy experiments have been performed in which the light from a cw tunable dye laser interacts at right angles with a thermal atomic beam. sup(76-98)Rb, sup(118-145)Cs and sup(208-213)Fr have been studied using the ionic beam delivered by the ISOLDE on-line mass separator at CERN while sup(20-31)Na and sup(38-47)K have been studied by setting the apparaturs directly on-line with the PS 20 GeV proton beam. The principle of the method is briefly explained and some results concerning nuclear structure are given. (orig.)

  2. Development of the collinear laser beam line at TRIUMF

    Science.gov (United States)

    Levy, C. D. P.; Pearson, M. R.; Morris, G. D.; Chow, K. H.; Hossain, M. D.; Kiefl, R. F.; Labbé, R.; Lassen, J.; Macfarlane, W. A.; Parolin, T. J.; Saadaoui, H.; Smadella, M.; Song, Q.; Wang, D.

    2010-02-01

    The low-energy collinear laser beam line at ISAC routinely produces highly nuclear-spin polarized beams of 8Li + for depth-controlled studies of thin films and near-surface phenomena. It also is used for nuclear structure and fundamental symmetry studies requiring other beams of polarized lithium and sodium isotopes. Further development of polarized 20F and 11Be beams is described, the latter in some detail. Laser fluorescence spectroscopy at high sensitivity using unpolarized bunched beams is briefly mentioned.

  3. Development of the collinear laser beam line at TRIUMF

    Energy Technology Data Exchange (ETDEWEB)

    Levy, C. D. P., E-mail: levy@triumf.ca; Pearson, M. R.; Morris, G. D. [TRIUMF (Canada); Chow, K. H. [University of Alberta, Department of Physics (Canada); Hossain, M. D. [University of British Columbia, Department of Physics and Astronomy (Canada); Kiefl, R. F. [TRIUMF (Canada); Labbe, R. [Universite Laval, Departement de Physique (Canada); Lassen, J. [TRIUMF (Canada); MacFarlane, W. A.; Parolin, T. J. [University of British Columbia, Chemistry Department (Canada); Saadaoui, H.; Smadella, M.; Song, Q.; Wang, D. [University of British Columbia, Department of Physics and Astronomy (Canada)

    2010-02-15

    The low-energy collinear laser beam line at ISAC routinely produces highly nuclear-spin polarized beams of {sup 8}Li{sup +} for depth-controlled studies of thin films and near-surface phenomena. It also is used for nuclear structure and fundamental symmetry studies requiring other beams of polarized lithium and sodium isotopes. Further development of polarized {sup 20}F and {sup 11}Be beams is described, the latter in some detail. Laser fluorescence spectroscopy at high sensitivity using unpolarized bunched beams is briefly mentioned.

  4. Computer simulation of high current uranium beams for the injection beam line of the UNILAC

    International Nuclear Information System (INIS)

    Xiang, W.; Spaedtke, P.; Hollinger, R.; Galonska, M.; Heymach, F.

    2004-07-01

    In an attempt to generate an ion beam with high current and high brightness for the design ion, the computer code KOBRA3-INP has been used to evaluate the extraction system, the DC post-acceleration system as well as the quadrupole transport beam line, and to study the behavior of the ion beam in the combined system. (orig.)

  5. Muon Beam Studies in the H4 beam line and the Gamma Irradiation Facility (GIF++)

    CERN Document Server

    Margraf, Rachel; CERN. Geneva. ATS Department

    2018-01-01

    In this note, we present detailed simulation results for the trajectory of a muon beam, traversing beam zones PPE-134 and PPE-154, produced by a 150 GeV positive hadron beam incident on collimators 9 & 10 in the H4 beam line when these collimators are placed off-beam axis to stop all hadrons and electrons. Using G4Beamline, a GEANT-4 based Monte-Carlo program, the trajectory of the muon beam has been studied for several field strengths of the GOLIATH magnet, as well as for different polarities. The position of the beam at the Gamma Irradiation Facility (GIF++), located downstream the PPE-144 area, is also presented. In addition, two configurations of the two XTDV’s present in the line (XTDV.022.520 and XTDV.022.610) have been studied, with the purpose to simulate the pion contamination of the beam both in PPE134 and GIF++.

  6. Investigation of Beam Emittance and Beam Transport Line Optics on Polarization

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Andrew [Northern Illinois U.; Syphers, Michael [Fermilab

    2017-10-06

    Effects of beam emittance, energy spread, optical parameters and magnet misalignment on beam polarization through particle transport systems are investigated. Particular emphasis will be placed on the beam lines being used at Fermilab for the development of the muon beam for the Muon g-2 experiment, including comparisons with the natural polarization resulting from pion decay, and comments on the development of systematic correlations among phase space variables.

  7. The SPS beam lines to the West Hall

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The proton beam arriving from bottom is cut into three parts by the special steel septum magnets, seen in the centre, and then focussed onto the targets just out the sight on the top. The beam line near the right hand wall carries an RF-separated beam to BEBC from a target located deep in the TT60 tunnel. (Annual Report 1976 p. 116)

  8. Analysis of particle species evolution in neutral beam injection lines

    International Nuclear Information System (INIS)

    Kim, J.; Haselton, H.H.

    1978-07-01

    Analytic solutions to the rate equations describing the species evolution of a multispecies positive ion beam of hydrogen due to charge exchange and molecular dissociation are derived as a function of the background gas (H 2 ) line density in the neutralizing gas cell and in the drift tube. Using the solutions, calculations are presented for the relative abundance of each species as a function of the gas cell thickness, the reionization loss rates in the drift tube, and the neutral beam power as a function of the beam energy and the species composition of the original ion beam

  9. A beam position feedback system for beam lines at the photon factory

    International Nuclear Information System (INIS)

    Katsura, T.; Kamiya, Y.; Haga, K.; Mitsuhashi, T.

    1987-01-01

    The beam position of the synchrotron radiation produced from the Storage Ring was stabilized by a twofold position feedback system. A digital feedback system was developed to suppress the diurnal beam movement (one cycle of sin-like drifting motion per day) which became a serious problem in low-emittance operation. The feedback was applied to the closed-orbit-distortion (COD) correction system in order to cancel the position variation at all the beam lines proportionately to the variation monitored at one beam line. An analog feedback system is also used to suppress frequency components faster than the slow diurnal movement

  10. An electromagnetically focused electron beam line source

    International Nuclear Information System (INIS)

    Iqbal, Munawar; Masood, Khalid; Rafiq, Mohammad; Chaudhary, Maqbool A.; Aleem, Fazal-e-

    2003-01-01

    A directly heated thermionic electron beam source was constructed. A tungsten wire of length 140 mm with diameter 0.9 mm was used as a cathode. An emission current of 5000 mA was achieved at an input heating power of 600 W. Cathode to anode distance of 6 mm with acceleration voltage of 10 kV was used. A uniform external magnetic field of 50 G was employed to obtain a well-focused electron beam at a deflection of 180 deg., with cathode to work site distance of 130 mm. Dimensions of the beam (1.25x120 mm) recorded at the work site were found to be in good agreement with the designed length of cathode. The deformation of the cathode was overcome by introducing a spring action mechanism, which gives uniform emission current density throughout the emission surface. We have achieved the saturation limit of the designed source resulting in smooth and swift operation of the gun for many hours (10-15 h continuously). The design of gun is so simple that it can accommodate longer cathodes for obtaining higher emission values. This gun has made it possible to coat large substrate surfaces at much faster evaporation rate at lower cost. It can also be useful in large-scale vacuum metallurgy plants for melting, welding and heat treatment

  11. The beam diagnostic instruments in Beijing radioactive ion-beam facilities isotope separator on-line

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Y., E-mail: yjma@ciae.ac.cn; Cui, B.; Ma, R.; Tang, B.; Chen, L.; Huang, Q.; Jiang, W. [China Institute of Atomic Energy, Beijing 102413 (China)

    2014-02-15

    The beam diagnostic instruments for Beijing Radioactive Ion-beam Facilities Isotope Separator On-Line are introduced [B. Q. Cui, Z. H. Peng, Y. J. Ma, R. G. Ma, B. Tang, T. Zhang, and W. S. Jiang, Nucl. Instrum. Methods 266, 4113 (2008); T. J. Zhang, X. L. Guan, and B. Q. Cui, in Proceedings of APAC 2004, Gyeongju, Korea, 2004, http://www.jacow.org , p. 267]. For low intensity ion beam [30–300 keV/1 pA–10 μA], the beam profile monitor, the emittance measurement unit, and the analyzing slit will be installed. For the primary proton beam [100 MeV/200 μA], the beam profile scanner will be installed. For identification of the nuclide, a beam identification unit will be installed. The details of prototype of the beam diagnostic units and some experiment results will be described in this article.

  12. The beam diagnostic instruments in Beijing radioactive ion-beam facilities isotope separator on-line

    Science.gov (United States)

    Ma, Y.; Cui, B.; Ma, R.; Tang, B.; Chen, L.; Huang, Q.; Jiang, W.

    2014-02-01

    The beam diagnostic instruments for Beijing Radioactive Ion-beam Facilities Isotope Separator On-Line are introduced [B. Q. Cui, Z. H. Peng, Y. J. Ma, R. G. Ma, B. Tang, T. Zhang, and W. S. Jiang, Nucl. Instrum. Methods 266, 4113 (2008); T. J. Zhang, X. L. Guan, and B. Q. Cui, in Proceedings of APAC 2004, Gyeongju, Korea, 2004, http://www.jacow.org, p. 267]. For low intensity ion beam [30-300 keV/1 pA-10 μA], the beam profile monitor, the emittance measurement unit, and the analyzing slit will be installed. For the primary proton beam [100 MeV/200 μA], the beam profile scanner will be installed. For identification of the nuclide, a beam identification unit will be installed. The details of prototype of the beam diagnostic units and some experiment results will be described in this article.

  13. Dipole corrector magnets for the LBNE beam line

    Energy Technology Data Exchange (ETDEWEB)

    Yu, M.; Velev, G.; Harding, D.; /Fermilab

    2011-03-01

    The conceptual design of a new dipole corrector magnet has been thoroughly studied. The planned Long-Baseline Neutrino Experiment (LBNE) beam line will require correctors capable of greater range and linearity than existing correctors, so a new design is proposed based on the horizontal trim dipole correctors built for the Main Injector synchrotron at Fermilab. The gap, pole shape, length, and number of conductor turns remain the same. To allow operation over a wider range of excitations without overheating, the conductor size is increased, and to maintain better linearity, the back leg thickness is increased. The magnetic simulation was done using ANSYS to optimize the shape and the size of the yoke. The thermal performance was also modeled and analyzed.

  14. Construction of a pulsed MeV positron beam line

    Energy Technology Data Exchange (ETDEWEB)

    Masuno, Shin-ichi; Okada, Sohei; Kawasuso, Atsuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    To develop a fast (1 MeV) and short pulsed (100 ps) positron beam which enables defect behavior analysis of bulk states of materials even at high temperatures where a usual positron source would melt, we have been performing design study and construction of the beam line in a three-year program since 1994. This report describes the components, design study results and experimental results of the completed parts until now. (author)

  15. Simulating the Beam-line at CERN's ISOLDE Experiment

    CERN Document Server

    McGrath, Casey

    2013-01-01

    Maximizing the optical matching along portions of the ISOLDE beam-line and automating this procedure will make it easier for scientists to determine what the strengths of the electrical elds of each beam-line element should be in order to reduce particle loss. Simulations are run using a program called MAD-X, however, certain issues were discovered that hindered an immediate success of the simulations. Specifically, the transfer matrices for electrostatic components like the switchyards, kickers, and electric quadrupoles were missing from the original coding. The primary aim of this project was to design these components using AutoCAD and then extract the transfer matrices using SIMION. Future work will then implement these transfer matrices into the MAD-X code to make the simulations of the beam-line more accurate.

  16. Beam lines from Linac 1 to PS and Booster

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    View against the direction of the proton beams. The 50 MeV Linac 1 is behind the concrete wall. Its beam emerges from the hole near the centre of the picture. A switching magnet directs the beam either to the PS (to the right in the sense of the beam; original injection line), or lets it go straight on to the Booster (originally 800 MeV, now 1.4 GeV). The huge drum in the line to the Booster is a "debuncher", driven by the 200 MHz RF of the linac. It reduces the beam's momentum spread. This was the last year of Linac 1 as provider of protons to the Booster. Linac 2, nearly completed at the time of this picture, took up trial delivery at the end of 1978, and routine delivery in 1979. The beam line from Linac 2, barely visible here, can be clearly seen on 7802260. Linac 1 had a second life as an ion accelerator.

  17. Off-line system for particle beam diagnostics

    International Nuclear Information System (INIS)

    Basiladze, S.G.; Komolov, L.N.; Yudin, V.K.

    1979-01-01

    An off-line system in the CAMAC standard for beam diagnostics with the help of proportional chambers and the NTA-512B analyzer is described. The maximum number of wires in the system is 512. The accuracy of beam profile presentation is increased by selection of single-wire operations. The inquire time of one proportional chamber constitutes 15-20 μs and is comparable to the analyzer recording cycle. As a result, six chambers can detect 3000 particles per one accelerator cycle at the beam extraction duration of 400 ms. The system can be connected to a computer

  18. Note: Characteristic beam parameter for the line electron gun.

    Science.gov (United States)

    Iqbal, M; Islam, G U; Zhou, Z; Chi, Y

    2013-11-01

    We have optimized the beam parameters of line source electron gun using Stanford Linear Accelerator Centre electron beam trajectory program (EGUN), utilizing electrostatic focusing only. We measured minimum beam diameter as 0.5 mm that corresponds to power density of 68.9 kW/cm(2) at 13.5 mm in the post-anode region which is more than two-fold (33 kW/cm(2)), of the previously reported results. The gun was operated for the validation of the theoretical results and found in good agreement. The gun is now without any magnetic and electrostatic focusing thus much simpler and more powerful.

  19. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test

    International Nuclear Information System (INIS)

    Jana, M.R.; Bross, A.; Chung, M.; Greer, S.; Johnstone, C.; Kobilarcik, T.; Koizumi, G.; Leonova, M.; Moretti, A.; Popovic, M.; Schwartz, T.

    2012-01-01

    Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is ∼ 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.

  20. E-line: A new crystal collimator beam line for source size measurements at CHESS

    International Nuclear Information System (INIS)

    White, Jeffrey A.; Revesz, Peter; Finkelstein, Ken

    2007-01-01

    A new X-ray beam line has been constructed at cornell high energy synchrotron source (CHESS) to measure the vertical and horizontal source size of the positron particle beam. The cornell laboratory of elementary particle physics (LEPP) operates the storage ring (CESR) for X-ray generation for the CHESS user community by circulating electrons and their antimatter counterpart positrons in counter-rotating beams. As the laboratory reduces the emittances of particle beams to increase X-ray brilliance, there has been an increasing need for diagnostic tools to measure and monitor source size. A beam line front end that accesses the positron synchrotron light has been fitted with an experimental chamber and apparatus of compact design capable of horizontal and vertical source size measurement using the 'crystal collimator' technique, and an additional setup for vertical beam position monitoring using a luminescence-based X-ray video beam position monitoring system. The crystal collimators each consist of two Si(2 2 0) crystals in a dispersive (+,+) arrangement that diffract X-rays to a fluorescent material coated on a view port observed with a CCD camera. Measurements of the positron vertical beam size using the crystal collimation method at E-line are compared with measurements of visible synchrotron light at a remotely located dedicated port on the storage ring

  1. On setting magnets in the PEP beam-transport line

    International Nuclear Information System (INIS)

    Peterson, J.M.

    1979-01-01

    This paper discusses magnets in the PEP beam-transport line. Topics discussed are: conditioning, direction of excitation, rate of excitation; determination of the excitation current for the principal bend magnets; steering mechanisms; bump magnets; and determination of excitation currents of the quadrupole magnets

  2. Confining continuous manipulations of accelerator beam-line optics

    Directory of Open Access Journals (Sweden)

    Ph. Amstutz

    2017-04-01

    Full Text Available Altering the optics in one section of a linear accelerator beam line will in general cause an alteration of the optics in all downstream sections. In circular accelerators, changing the optical properties of any beam-line element will have an impact on the optical functions throughout the whole machine. In many cases, however, it is desirable to change the optics in a certain beam-line section without disturbing any other parts of the machine. Such a local optics manipulation can be achieved by adjusting a number of additional corrector magnets that restore the initial optics after the manipulated section. In that case, the effect of the manipulation is confined in the region between the manipulated and the correcting beam-line elements. Introducing a manipulation continuously, while the machine is operating, therefore requires continuous correction functions to be applied to the correcting quadrupole magnets. In this paper, we present an approach to calculate such continuous correction functions for six quadrupole magnets by means of a homotopy method. Besides a detailed derivation of the method, we present its application to an algebraic example, as well as its demonstration at the seeding experiment sFLASH at the free-electron laser FLASH located at DESY in Hamburg.

  3. A polarized beam for the M-3 line

    International Nuclear Information System (INIS)

    Underwood, D.; Colton, E.; Halpern, H.

    1978-01-01

    A beamline is proposed for polarized protons to be built in the M-3 line of the Meson Laboratory utilizing lambda decays. This beamline would provide a clean source of polarized protons or an enriched beam of antiprotons or polarized antiprotons

  4. Consistency checks in beam emission modeling for neutral beam injectors

    International Nuclear Information System (INIS)

    Punyapu, Bharathi; Vattipalle, Prahlad; Sharma, Sanjeev Kumar; Baruah, Ujjwal Kumar; Crowley, Brendan

    2015-01-01

    In positive neutral beam systems, the beam parameters such as ion species fractions, power fractions and beam divergence are routinely measured using Doppler shifted beam emission spectrum. The accuracy with which these parameters are estimated depend on the accuracy of the atomic modeling involved in these estimations. In this work, an effective procedure to check the consistency of the beam emission modeling in neutral beam injectors is proposed. As a first consistency check, at a constant beam voltage and current, the intensity of the beam emission spectrum is measured by varying the pressure in the neutralizer. Then, the scaling of measured intensity of un-shifted (target) and Doppler shifted intensities (projectile) of the beam emission spectrum at these pressure values are studied. If the un-shifted component scales with pressure, then the intensity of this component will be used as a second consistency check on the beam emission modeling. As a further check, the modeled beam fractions and emission cross sections of projectile and target are used to predict the intensity of the un-shifted component and then compared with the value of measured target intensity. An agreement between the predicted and measured target intensities provide the degree of discrepancy in the beam emission modeling. In order to test this methodology, a systematic analysis of Doppler shift spectroscopy data obtained on the JET neutral beam test stand data was carried out

  5. Characteristics of Sissi beams in the transport lines of Ganil

    International Nuclear Information System (INIS)

    Nghiem, P.; Payet, J.; Tkatchenko, A.

    1994-01-01

    This study is the following of the Sissi primary beam characteristics definition. Its aim is to determine the performances in resolution and in transmission of transport lines which guide the secondary beams until the experimentation rooms. The first part concerns the study of the secondary order characteristics with the help of BETA matrix code for the nominal case. The second part is the same study but but of superior orders carried out with the Zgoubi program. The third part consists to search new regulating to minimise the losses of particles due to the effect of non-linearity. (O.L.). 3 refs., 34 figs., 5 tabs

  6. Performance of the Culham multi-megawatt beam line facility

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, D.P.; Cottrell, G.A.; Coupland, J.R.

    1981-01-01

    The Culham Megawatt Beam Line has been upgraded in order to test injector modules for the JET experiment. The major items provided are: a high voltage modulator tube system, modified auxiliary supplies, new vacuum tanks and cryopumps, a high power beam pump, additional tanks and cryopumps, a high power data acquisition system. Delivery of the first complete JET prototype source and accelerator was scheduled for the end of 1981. The major components, having been tested separately as far as possible, are now installed and are being tested up to the 80kV, 12A level of the existing plasma source.

  7. Performance of the Culham multi-megawatt beam line facility

    International Nuclear Information System (INIS)

    Hammond, D.P.; Cottrell, G.A.; Coupland, J.R.

    1981-01-01

    The Culham Megawatt Beam Line has been upgraded in order to test injector modules for the JET experiment. The major items provided are: a high voltage modulator tube system, modified auxiliary supplies, new vacuum tanks and cryopumps, a high power beam pump, additional tanks and cryopumps, a high power data acquisition system. Delivery of the first complete JET prototype source and accelerator was scheduled for the end of 1981. The major components, having been tested separately as far as possible, are now installed and are being tested up to the 80kV, 12A level of the existing plasma source

  8. Beam manipulation and acceleration with Dielectric-Lined Waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Lemery, Francois [Northern Illinois Univ., DeKalb, IL (United States)

    2015-06-01

    The development of next-generation TeV+ electron accelerators will require either immense footprints based on conventional acceleraton techniques or the development of new higher{gradient acceleration methods. One possible alternative is beam-driven acceleration in a high-impedance medium such as a dielectric-lined-waveguide (DLW), where a highcharge bunch passes through a DLW and can excite gradients on the order of GV/m. An important characteristic of this acceleration class is the transformer ratio which characterizes the energy transfer of the scheme. This dissertation discusses alternative methods to improve the transformer ratio for beam-driven acceleration and also considers the use of DLWs for beam manipulation at low energy.

  9. Intelligent mirror monitor and controller for synchrotron radiation beam lines

    International Nuclear Information System (INIS)

    Xu, X.L.; Yang, J.

    1983-01-01

    A microprocessor-based, stand-alone mirror monitor and control system has been developed for synchrotron radiation beam lines. The operational requirements for mirror position and tilt angle, including the parameters for controlling the number of steps, direction, speed and acceleration of the driving motors, may be programmed into EPROMS. The instruction sequence to carry out critical motions will be stored in a program buffer. A manual control knob is also provided to fine tune the mirror position if desired. A synchronization scheme for the height and tilt motions maintains a fixed mirror angle during insertion. Absolute height and tilt angle are displayed. Electronic (or programmable) tilt angle limits are provided to protect against damage from misalignment of high power beams such as focussed wiggler beams. A description of mirror drives with a schematic diagram is presented. Although the controller is made for mirror movers, it can be used in other applications where multiple stepping motors perform complex synchronized motions

  10. The H line: a brand new beam line for fundamental physics at the J-PARC muon facility

    International Nuclear Information System (INIS)

    Kawamura, N; Shimomura, K; Miyake, Y; Toyoda, A; Saito, N; Mihara, S; Aoki, M

    2013-01-01

    The muon facility, J-PARC (Muon Science Establishment; MUSE), has been operated since first beam in 2008. Starting with a 200 kW proton beam, the beam intensity has reached 3×10 6 / muons/s, the most intense pulsed muon beam in the world. A 2 cm thick graphite target permits the extraction of four secondary muon beams. A brand new beam line, the H line, is planned to be constructed. The new beam line is designed to have a large acceptance, will provide the ability to tune the momentum, and use a kicker magnet and/or Wien filter. This beam line will provide an intense beam for experiments that require high statistics and must occupy the experimental areas for a relatively long period.

  11. Physics at the new CERN neutron beam line

    CERN Document Server

    Guerrero, C

    2014-01-01

    A new neutron beam line (n_TOF EAR - 2) is being built at CERN within the n_TOF facility. Compared to the existing 185 meters long time - of - flight beam line, the new one (which will operate in parallel) will feature a shorter flight of 20 meters, providing a 2 7 times more intense neutron flux extending from thermal to 300 MeV. The scientific program is now bein g discussed and the first detailed proposals will be refereed by February 2014. This contribution is devoted to present and discuss the expected performance of the facility, briefly, and the details of some of the first measureme nts foreseen for 2014 and 2015.

  12. Beam line design for synchrotron spectroscopy in the VUV

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M R

    1980-01-01

    The character of the radiation source provided by an electron storage ring is briefly reviewed from the point of view of utilization for VUV spectroscopy. The design of beam line components is then considered with special reference to the problems of contamination of optical surfaces and vacuum protection. The issues involved in designing mirrors for use with storage rings are considered with emphasis on the questions of power dissipation, image quality and materials selection.

  13. Beam line design for synchrotron spectroscopy in the VUV

    International Nuclear Information System (INIS)

    Howells, M.R.

    1980-01-01

    The character of the radiation source provided by an electron storage ring is briefly reviewed from the point of view of utilization for VUV spectroscopy. The design of beam line components is then considered with special reference to the problems of contamination of optical surfaces and vacuum protection. The issues involved in designing mirrors for use with storage rings are considered with emphasis on the questions of power dissipation, image quality and materials selection

  14. High energy beam line based on bent crystal

    International Nuclear Information System (INIS)

    Biryukov, V.M.; Chesnokov, Yu.A.; Greth, V.N.; Ivanov, A.A.; Kotov, V.I.; Selesnev, V.S.; Tarakanov, M.V.; Terekhov, V.I.; Tsarik, S.V.

    1995-01-01

    A peculiarities of the beam bent with crystals is the independence of the crystal deflector strength Θ=L D /R c ∼0.5 rad of the particle energy (L D is the dechanneling length, R c is the critical radius). The possibility of abrupt bending with crystal of a beam fraction at a large angle allows one to make over a short base a non-traditional beam line to carry out physical experiments. At IHEP, a 150 mrad bent crystal was used to create a test area, to work in parallel with other set-ups consuming practically no power. A 100 mm long Si crystal, placed in the halo of the intense extracted 70 GeV/c beam, extracts along the ∼20 m base 10 6 protons/sec beyond the 2-meter iron-concrete shield. The beam high quality (low emittance and high stability) allows one to carry out the program of the studies of channeling and testing the microstrip detectors. 2 refs.; 2 figs

  15. On- and off-line monitoring of ion beam treatment

    Science.gov (United States)

    Parodi, Katia

    2016-02-01

    Ion beam therapy is an emerging modality for high precision radiation treatment of cancer. In comparison to conventional radiation sources (photons, electrons), ion beams feature major dosimetric advantages due to their finite range with a localized dose deposition maximum, the Bragg peak, which can be selectively adjusted in depth. However, due to several sources of treatment uncertainties, full exploitation of these dosimetric advantages in clinical practice would require the possibility to visualize the stopping position of the ions in vivo, ideally in real-time. To this aim, different imaging methods have been proposed and investigated, either pre-clinically or even clinically, based on the detection of prompt or delayed radiation following nuclear interaction of the beam with the irradiated tissue. However, the chosen or ad-hoc developed instrumentation has often relied on technologies originally conceived for different applications, thus compromising on the achievable performances for the sake of cost-effectiveness. This contribution will review major examples of used instrumentation and related performances, identifying the most promising detector developments for next generation devices especially dedicated to on-line monitoring of ion beam treatment. Moreover, it will propose an original combination of different techniques in a hybrid detection scheme, aiming to make the most of complementary imaging methods and open new perspectives of image guidance for improved precision of ion beam therapy.

  16. Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

    Science.gov (United States)

    Scisciò, M.; Lancia, L.; Migliorati, M.; Mostacci, A.; Palumbo, L.; Papaphilippou, Y.; Antici, P.

    2016-03-01

    In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupoles and solenoids) as an easy implementable solution when the laser-plasma accelerated beam requires optimization. In this paper, we report on a parametric study related to the transport of electron beams accelerated by laser-plasma interaction, using conventional accelerator elements and tools. We focus on both, high energy electron beams in the GeV range, as produced on petawatt (PW) class laser systems, and on lower energy electron beams in the hundreds of MeV range, as nowadays routinely obtained on commercially available multi-hundred TW laser systems. For both scenarios, our study allows understanding what are the crucial parameters that enable laser-plasma accelerators to compete with conventional ones and allow for a beam transport. We show that suitable working points require a tradeoff-combination between low beam divergence and narrow energy spread.

  17. Modeling FAMA ion beam diagnostics based on the Ptolemy II model

    Energy Technology Data Exchange (ETDEWEB)

    Balvanovic, R., E-mail: broman@vinca.rs [Laboratory of Physics, Vinca Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001 Belgrade (Serbia); Belicev, P. [Laboratory of Physics, Vinca Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001 Belgrade (Serbia); Radjenovic, B. [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia)

    2012-10-21

    The previously developed model of ion beam transport control of the FAMA facility is further enhanced by equipping it with the model of ion beam diagnostics. The model of control, executing once, is adjusted so that it executes in iterative mode, where each iteration samples the input beam normally distributed over initial phase space and calculates a single trajectory through the facility beam lines. The model takes into account only the particles that manage to pass through all the beam line apertures, emulating in this way a Faraday cup and a beam profile meter. Generated are also beam phase space distributions and horizontal and vertical beam profiles at the end of the beam transport lines the FAMA facility consists of. By adding the model of ion beam diagnostics to the model of ion beam transport control, the process of determining optimal ion beam control parameters is eased and speeded up, and the understanding of influence of control parameters on the ion beam characteristics is improved.

  18. Beam optics of the AmPS extraction line

    International Nuclear Information System (INIS)

    Hoekstra, R.

    1991-01-01

    The design of the Amsterdam Pulse Stretcher includes a feasibility study of part of the extraction trajectory. The latter includes some proposed curves projected through the hall of the beam switch yard. Since extraction is performed in the north line of the ring and the connection to the trajectory of the spectrometers is planned in a trajectory parallel to the east line of the ring the curves contain bending magnets for bending 90 degrees either by only two magnets or by making use of ring bending magnets in the same way as the ring curves are constructed. The bending through 90 degrees has optimal imaging properties of a unit cell much the same as the curves in the ring. This one-to-one (or one-to-minus-one) property is intended to shift the known required beam dimensions stream upwards from a defined point in the trajectory of the spectrometers to be able to create the dimensions at this shifted point by means of a so called beam transformer, placed in between the extraction point and this position. This report deals with the further developments with respect to the extraction trajectory. (author). 5 refs.; 9 figs.; 3 tabs

  19. Beam profile monitor system for the bevalac transfer line

    International Nuclear Information System (INIS)

    Stover, G.

    1985-01-01

    Incorporated in the current Bevalac transfer line upgrade project is a proposal for a new electronic beam monitoring system. It will be designed to amplify, convert, and transmit the signals of twelve 16 by 16 multi-wire grids to a central computer located in the Bevatron control room. Each station will contain interface amplifiers and a local microprocessor to convert wire grid currents into digitized values which will then be transmitted via a serial data channel to the main computer. The system will have a large dynamic range (1 nano to 1 milli-ampere of beam current), be designed for distributed operation, and will be easily expandable. This paper describes the basic electronic hardware and software components of the proposed system

  20. Issues for Bringing Electron Beam Irradiators On-Line

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, R.J.; Turman, B.N.

    1999-04-20

    Irradiation of red meat and poultry has been approved by the U.S. FDA, and the U.S. Department of Agriculture's rule for processing red meat is out for comment. Looking beyond the current issues of packaging materials, labeling, and consumer acceptance, this paper reviews the next step of implementation and how to remove, or at least reduce, the barriers to utilization. Polls of the user community identified their requirements for electron beam or x-ray processing of meat or poultry and their concerns about implementation for on-line processing. These needs and issues are compared to the capabilities of the accelerator industry. The critical issues of beam utilization and dose uniformity, factors affecting floor space requirements, and treatment costs are examined.

  1. High current nonlinear transmission line based electron beam driver

    Directory of Open Access Journals (Sweden)

    B. W. Hoff

    2017-10-01

    Full Text Available A gigawatt-class nonlinear transmission line based electron beam driver is experimentally demonstrated. Four experimental series, each with a different Marx bank charge voltage (15, 20, 25, and 30 kV, were completed. Within each experimental series, shots at peak frequencies ranging from 950 MHz to 1.45 GHz were performed. Peak amplitude modulations of the NLTL output voltage signal were found to range between 18% and 35% for the lowest frequency shots and between 5% and 20% for the highest frequency shots (higher modulation at higher Marx charge voltage. Peak amplitude modulations of the electron beam current were found to range between 10% and 20% for the lowest frequency shots and between 2% and 7% for the highest frequency shots (higher modulation at higher Marx charge voltage.

  2. High current nonlinear transmission line based electron beam driver

    Science.gov (United States)

    Hoff, B. W.; French, D. M.; Simon, D. S.; Lepell, P. D.; Montoya, T.; Heidger, S. L.

    2017-10-01

    A gigawatt-class nonlinear transmission line based electron beam driver is experimentally demonstrated. Four experimental series, each with a different Marx bank charge voltage (15, 20, 25, and 30 kV), were completed. Within each experimental series, shots at peak frequencies ranging from 950 MHz to 1.45 GHz were performed. Peak amplitude modulations of the NLTL output voltage signal were found to range between 18% and 35% for the lowest frequency shots and between 5% and 20% for the highest frequency shots (higher modulation at higher Marx charge voltage). Peak amplitude modulations of the electron beam current were found to range between 10% and 20% for the lowest frequency shots and between 2% and 7% for the highest frequency shots (higher modulation at higher Marx charge voltage).

  3. Issues for Bringing Electron Beam Irradiators On-Line

    International Nuclear Information System (INIS)

    Kaye, R.J.; Turman, B.N.

    1999-01-01

    Irradiation of red meat and poultry has been approved by the U.S. FDA, and the U.S. Department of Agriculture's rule for processing red meat is out for comment. Looking beyond the current issues of packaging materials, labeling, and consumer acceptance, this paper reviews the next step of implementation and how to remove, or at least reduce, the barriers to utilization. Polls of the user community identified their requirements for electron beam or x-ray processing of meat or poultry and their concerns about implementation for on-line processing. These needs and issues are compared to the capabilities of the accelerator industry. The critical issues of beam utilization and dose uniformity, factors affecting floor space requirements, and treatment costs are examined

  4. Noninterceptive beam energy measurements in line D of the Los Alamos Meson Physics Facility

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.; Carter, H.; Plum, M.; Power, J.F.; Rose, C.R.; Shurter, R.B.

    1995-01-01

    Several members of the Accelerator and Operations Technology (AOT) division beam-diagnostics team performed time-of-flight (TOF) beam-energy measurements in line D of the Los Alamos Meson Physics Facility (LAMPF) using developmental beam time. These measurements provided information for a final design of an on-line beam energy measurement. The following paper discusses these measurements and how they apply to the final beam energy measurement design

  5. An interactive beam line simulator module for RHIC

    International Nuclear Information System (INIS)

    MacKay, W.W.

    1997-01-01

    This paper describes the interactive simulation engine, bl, designed for the RHIC project. The program tracks as output to shared memory the central orbit, Twiss and dispersion functions, as well as the 6 x 6 beam hyperellipsoid. Transfer matrices between elements are available via interactive requests. Using a 6-d model, optical elements are modeled with a linear transfer matrix and a vector. The vector allows simulation of misalignments, shifts in field strengths, and beam rigidity. Currently only a linear model is used for elements. In addition to the usual magnets, a foil element is included which can shift the beam's rigidity (resulting from a change of charge and energy loss), as well as increase the momentum spread and emittance. Running as a Glish client, bl can be interfaced to other programs, such as an orbit plotter and a power supply application to give a quick prediction of the beam orbit from actual operating currents in the accelerator. Various strengths and offsets may be changed by sending Glish events to bl

  6. Beam Dumps and Beam Stoppers for LHC and CNGS Transfer Lines

    CERN Document Server

    Péraire, S

    2001-01-01

    Three new beam transfer lines are presently under construction at the SPS: TI2 and TI8 which will transfer protons and ions to the LHC, and TT41 which will transfer protons to the CNGS neutrino target. Three beam dumps (TED) and two beam stoppers (TBSE) will be installed in TI2 and TI8, and one TBSE in TT41. Both types of equipment are required to intercept the 450 GeV SPS beams concentrated in very short pulses (7.8 µs-10.5 µs) at intensities up to ~ 5 10**13 protons, every 16.8 seconds for the TED and as single shot for the TBSE. The outer TED iron shielding will be identical to the existing SPS one, while dimensions and material composition of both TED and TBSE cores have been optimised to cope with the new beam conditions. The optimised TED inner core consists of a Ø80 mm graphite cylinder 2.9 m long, housed into a Ø80/160 mm aluminium blind tube 3.5 m long, itself fitted into a Ø160/310 mm copper blind tube 4.3 m long. The TBSE is made of the same graphite cylinder, housed into a Ø80/120 mm alumin...

  7. Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, C.; Halama, H.; Thomlinson, W.

    1986-10-01

    Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures. (LEW)

  8. Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A

    International Nuclear Information System (INIS)

    Foerster, C.; Halama, H.; Thomlinson, W.

    1986-10-01

    Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures

  9. Geant4 simulations of proton beam transport through a carbon or beryllium degrader and following a beam line

    NARCIS (Netherlands)

    van Goethem, M. J.; van der Meer, R.; Reist, H. W.; Schippers, J. M.

    2009-01-01

    Monte Carlo simulations based on the Geant4 simulation toolkit were performed for the carbon wedge degrader used in the beam line at the Center of Proton Therapy of the Paul Scherrer Institute (PSI). The simulations are part of the beam line studies for the development and understanding of the

  10. Investigation of the flat-beam model of the beam-beam interaction

    Directory of Open Access Journals (Sweden)

    Bjoern S. Schmekel

    2003-10-01

    Full Text Available At the interaction point of a storage ring collider each beam is subject to perturbations due to the electromagnetic field of the counterrotating beam. For flat beams, a well-known approximation models the beam by a current sheet which is uniform in the horizontal plane, restricting the particle motion to the vertical direction. In this classical model a water-bag beam distribution has been used to find working points and beam-beam tune shift parameters which lead to a stable beam distribution. We investigate the stability of a more realistic Gaussian equilibrium distribution. A linearized Vlasov equation written in action-angle variables is used to compute the radial and angular modes of a perturbation in two-dimensional phase space to first order in the displacement from the design trajectory. We find that the radial modes, which are often neglected, can have a stabilizing effect on the beam motion.

  11. RFQ Cooler and Buncher (and beam line section associated)

    CERN Document Server

    Podadera-Aliseda, I

    2003-01-01

    Developing a new RFQ cooler and buncher for ISOLDE. Such a device combines an energy loss in buffer gas atom-ion collisions with confinement provided by RF-field in transverse plane. Optional confinement in longitudinal direction is provided by static potential dwell. Then, an improvement of the beam line is achieved for all the experiments at ISOLDE. The RFQ operates inside a high voltage cage of 60 kV, and with a system of turbomulecular pumps both to keep the high vacuum before/after the RFQ and to keep a low pressure (around 0,1 mbar) inside the RFQ. The project is to be thought not only as a mechanical design and construction project, unless as a project of research and development, since it is about improving (operationally and technically) the existing RFQ cooler and buncher placed around the world. Due to ion optical reasons whole beam line section has to be redesigned and constructed as a part of this project.

  12. The 12-GeV/c beam transfer and absorber lines for the Superconducting Super Collider

    International Nuclear Information System (INIS)

    Mao, N.; McGill, J.; Gerig, R.; Brown, K.

    1994-08-01

    The beam optics of the 12-GeV/c proton beam transfer line between the Low Energy Booster (LEB) and the Medium Energy Booster (MEB) at the Superconducting Super Collider is presented. The beam is extracted from the LEB vertically and is injected into the MEB through a vertical Lambertson magnet and a horizontal kicker. The beamline has high flexibility for amplitude and dispersion function matching. Effects of various errors in the transfer line are studied, and a beam position correction scheme is proposed. The beam optics of the 12-GeV/c absorber line transporting the beam from the LEB to an absorber during the LEB commissioning is also presented

  13. Construction of Superconducting Magnet System for the J-PARC Neutrino Beam Line

    Energy Technology Data Exchange (ETDEWEB)

    Nakamoto, T.; Wanderer, P.; Sasaki, K.; Ajima, Y.; Araoka, O.; Fujii, Y.; Hastings, N.; Higashi, N.; Iida, M.; Ishii, T.; Kimura, N.; Kobayashi, T.; Makida, Y.; Nakadaira, T.; Ogitsu, T.; Ohhata, H.; Okamura, T.; Sakashita, K.; Sugawara, S.; Suzuki, S.; Tanaka, K.; Tomaru, T.; Terashima, A.; Yamamoto, A.; Ichikawa, A.; Kakuno, H.; Anerella, M.; Escallier, J.; Ganetis, G.; gupta, R.; Jain, A.; Muratore, J.; Parker, B.; Boussuge, T.; Charrier, J.-P.; Arakawa, M.; Ichihara, T.; Minato, T.; Okada, Y.; Itou, A.; Kumaki, T.; Nagami, M.; Takahashi, T.

    2009-10-18

    Following success of a prototype R&D, construction of a superconducting magnet system for J-PARC neutrino beam line has been carried out since 2005. A new conceptual beam line with the superconducting combined function magnets demonstrated the successful beam transport to the neutrino production target.

  14. Finite element modelling of composite castellated beam

    Directory of Open Access Journals (Sweden)

    Frans Richard

    2017-01-01

    Full Text Available Nowadays, castellated beam becomes popular in building structural as beam members. This is due to several advantages of castellated beam such as increased depth without any additional mass, passing the underfloor service ducts without changing of story elevation. However, the presence of holes can develop various local effects such as local buckling, lateral torsional buckling caused by compression force at the flange section of the steel beam. Many studies have investigated the failure mechanism of castellated beam and one technique which can prevent the beam fall into local failure is the use of reinforced concrete slab as lateral support on castellated beam, so called composite castellated beam. Besides of preventing the local failure of castellated beam, the concrete slab can increase the plasticity moment of the composite castellated beam section which can deliver into increasing the ultimate load of the beam. The aim of this numerical studies of composite castellated beam on certain loading condition (monotonic quasi-static loading. ABAQUS was used for finite element modelling purpose and compared with the experimental test for checking the reliability of the model. The result shows that the ultimate load of the composite castellated beam reached 6.24 times than the ultimate load of the solid I beam and 1.2 times compared the composite beam.

  15. Characterization of a tagged $\\gamma$-ray beam line at the DAFNE Beam Test Facility

    CERN Document Server

    Cattaneo, P W; Boffelli, F; Bulgarelli, A; Buonomo, B; Chen, A W; D’Ammando, F; FoggettA, L; Froysland, T; Fuschino, F; Galli, M; Gianotti, F; Giuliani, A; Longo, F; Marisaldi, M; Mazzitelli, G; Pellizzoni, A; Prest, M; Pucella, G; Quintieri, L; Rappoldi, A; Tavani, M; Trifoglio, M; Trois, A; Valente, P; Vallazza, E; Vercellone, S; Zambra, A; Barbiellini, G; Caraveo, P; Cocco, V; Costa, E; De Paris, G; Del Monte, E; Di Cocco, G; Donnarumma, I; Evangelista, Y; Feroci, M; Ferrari, A; Fiorini, M; Labanti, C; Lapshov, I; Lazzarotto, F; Lipari, P; Mastropietro, M; Mereghetti, S; Morelli, E; Moretti, E; Morselli, A; Pacciani, L; Perotti, F; Piano, G; Picozza, P; Pilia, M; Porrovecchio, G; Rapisarda, M; Rubini, A; Sabatini, S; Soffitta, P; Striani, E; Vittorini, V; Zanello, D; Colafrancesco, S; Giommi, P; Pittori, C; Santolamazza, P; Verrecchia, F; Salotti, L

    2012-01-01

    At the core of the AGILE scientific instrument, designed to operate on a satellite, there is the Gamma Ray Imaging Detector (GRID) consisting of a Silicon Tracker (ST), a Cesium Iodide Mini-Calorimeter and an Anti-Coincidence system of plastic scintillator bars. The ST needs an on-ground calibration with a γ-ray beam to validate the simulation used to calculate the energy response function and the effective area versus the energy and the direction of the γ rays. A tagged γ-ray beam line was designed at the Beam Test Facility (BTF) of the INFN Laboratori Nazionali of Frascati (LNF), based on an electron beam generating γ-rays through bremsstrahlung in a position-sensitive target. The γ-ray energy is deduced by difference with the post-bremsstrahlung electron energy [1] and [2]. The electron energy is measured by a spectrometer consisting of a dipole magnet and an array of position sensitive silicon strip detectors, the Photon Tagging System (PTS). The use of the combined BTF-PTS system as tagged photon be...

  16. submitter Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

    CERN Document Server

    Scisciò, M; Migliorati, M; Mostacci, A; Palumbo, L; Papaphilippou, Y; Antici, P

    2016-01-01

    In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupo...

  17. Computer controlled vacuum control system for synchrotron radiation beam lines

    International Nuclear Information System (INIS)

    Goldberg, S.M.; Wang, C.; Yang, J.

    1983-01-01

    The increasing number and complexity of vacuum control systems at the Stanford Synchrotron Radiation Laboratory has resulted in the need to computerize its operations in order to lower costs and increase efficiency of operation. Status signals are transmitted through digital and analog serial data links which use microprocessors to monitor vacuum status continuously. Each microprocessor has a unique address and up to 256 can be connected to the host computer over a single RS232 data line. A FORTRAN program on the host computer will request status messages and send control messages via only one RS232 line per beam line, signal the operator when a fault condition occurs, take automatic corrective actions, warn of impending valve failure, and keep a running log of all changes in vacuum status for later recall. Wiring costs are thus greatly reduced and more status conditions can be monitored without adding excessively to the complexity of the system. Operators can then obtain status reports at various locations in the lab quickly without having to read a large number of meter and LED's

  18. Grasshopper beam line for utilization of synchrotron radiation

    International Nuclear Information System (INIS)

    Saito, Norio; Suzuki, I.H.; Onuki, Hideo; Nishi, Morotake

    1989-01-01

    Optical characteristics of a new beam line consisting of a pre-mirror, a Grasshopper monochromator and a re-focusing mirror have been investigated. A ray-tracing calculation was performed for designing the mirrors so as to optimize the photon intensity and the spot size at the sample point. The intensity of the monochromatic soft x-ray was about 10 8 photons/(sec·100mA) at 25 A under the storage electron energy of 600 MeV with the minimum slit width which corresponded to a resolution of about 500. The sum of stray light and higher order components was less than 10% of the total intensity except around the C-K edge. Using an appropriate filter, it was reduced to less than a few percent. (author)

  19. An alternative beam line at the U-400 M cyclotron for RIB separation and transport to the FOBOS spectrometer (The technical proposal)

    International Nuclear Information System (INIS)

    Majdikov, V.Z.; Bashevoj, V.V.

    1998-01-01

    The first order ion-optic calculations performed together with the graphical modeling permits us to propose a new variant of the beam-transport line from the backside of the U-400M cyclotron to the FOBOS spectrometer. This beam line could be built in a rather short time without large financial expenditures from available magnetic and vacuum elements. The new beam line could even be considered as an economic alternative to the existing beam line and as a RIB separator. This work is the result of the pre-design R and D aimed to develop the U-400M cyclotron facilities for the RIB experiments performance with the FOBOS spectrometer

  20. Model-Independent Beam Dynamics Analysis

    International Nuclear Information System (INIS)

    Irwin, J.; Wang, C.X.; Yan, Y.T.; Bane, K.L.; Cai, Y.; Decker, F.; Minty, M.G.; Stupakov, G.V.; Zimmermann, F.

    1999-01-01

    Using a singular value decomposition of a beam line matrix, composed of many beam position measurements for a large number of pulses, together with the measurement of pulse-by-pulse beam properties or machine attributes, the contributions of each variable to the beam centroid motion can be identified with a greatly improved resolution. The eigenvalues above the noise floor determine the number of significant physical variables. This method is applicable to storage rings, linear accelerators, and any system involving a number of sources and a larger number of sensors with unknown correlations. Applications are presented from the Stanford Linear Collider. copyright 1999 The American Physical Society

  1. Extraction Compression and Acceleration of High Line Charge Density Ion Beams

    CERN Document Server

    Henestroza, Enrique; Grote, D P; Peters, Craig; Yu, Simon

    2005-01-01

    HEDP applications require high line charge density ion beams. An efficient method to obtain this type of beams is to extract a long pulse, high current beam from a gun at high energy, and let the beam pass through a decelerating field to compress it. The low energy beam bunch is loaded into a solenoid and matched to a Brillouin flow. The Brillouin equilibrium is independent of the energy if the relationship between the beam size (a), solenoid magnetic field strength (B) and line charge density is such that (Ba)2

  2. Millimeter-wave Line Ratios and Sub-beam Volume Density Distributions

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, Adam K.; Gallagher, Molly [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Usero, Antonio [Observatorio Astronmico Nacional (IGN), C/Alfonso XII, 3, E-28014 Madrid (Spain); Schruba, Andreas [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße 1, D-85748 Garching (Germany); Bigiel, Frank [Institute für theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle Str. 2, D-69120 Heidelberg (Germany); Kruijssen, J. M. Diederik; Schinnerer, Eva [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstraße 12-14, D-69120 Heidelberg (Germany); Kepley, Amanda [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Blanc, Guillermo A. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Bolatto, Alberto D. [Department of Astronomy, Laboratory for Millimeter-wave Astronomy, and Joint Space Institute, University of Maryland, College Park, MD 20742 (United States); Cormier, Diane; Jiménez-Donaire, Maria J. [Max Planck Institute für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Hughes, Annie [CNRS, IRAP, 9 av. du Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Rosolowsky, Erik [Department of Physics, University of Alberta, Edmonton, AB (Canada)

    2017-02-01

    We explore the use of mm-wave emission line ratios to trace molecular gas density when observations integrate over a wide range of volume densities within a single telescope beam. For observations targeting external galaxies, this case is unavoidable. Using a framework similar to that of Krumholz and Thompson, we model emission for a set of common extragalactic lines from lognormal and power law density distributions. We consider the median density of gas that produces emission and the ability to predict density variations from observed line ratios. We emphasize line ratio variations because these do not require us to know the absolute abundance of our tracers. Patterns of line ratio variations have the potential to illuminate the high-end shape of the density distribution, and to capture changes in the dense gas fraction and median volume density. Our results with and without a high-density power law tail differ appreciably; we highlight better knowledge of the probability density function (PDF) shape as an important area. We also show the implications of sub-beam density distributions for isotopologue studies targeting dense gas tracers. Differential excitation often implies a significant correction to the naive case. We provide tabulated versions of many of our results, which can be used to interpret changes in mm-wave line ratios in terms of adjustments to the underlying density distributions.

  3. New magnet transport system for the LHC beam transfer lines

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system (pictured here in one of the tunnels) is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. The lead vehicle is powered by an electric rail set into the roof of the tunnel. The system is backed up by electrical batteries that enable it to operate in the absence of an outside power source or in the event of power failure. Last but not least, for the long-distance transport of magnets, it can be optically guided by a line traced on the tunnel floor. The convoy moves through the particularly narr...

  4. Neutron beam-line shield design for the protein crystallography instrument at the Lujan Center

    International Nuclear Information System (INIS)

    Russell, G.J.; Pitcher, E.J.; Muhrer, G.; Ferguson, P.D.

    2001-01-01

    We have developed a very useful methodology for calculating absolute total (neutron plus gamma-ray) dose equivalent rates for use in the design of neutron beam line shields at a spallation neutron source. We have applied this technique to the design of beam line shields for several new materials science instruments being built at the Manuel Lujan Jr. Neutron Scattering Center. These instruments have a variety of collimation systems and different beam line shielding issues. We show here some specific beam line shield designs for the Protein Crystallography Instrument. (author)

  5. Modeling of active beam units with Modelica

    DEFF Research Database (Denmark)

    Maccarini, Alessandro; Hultmark, Göran; Vorre, Anders

    2015-01-01

    . Measurements from a full-scale experiment are used to compare the thermal behavior of the active beam with the one predicted by simulations. The simulation results show that the model corresponds closely with the actual operation. The model predicts the outlet water temperature of the active beam...... with a maximum mean absolute error of 0.18 °C. In term of maximum mean absolute percentage error, simulation results differ by 0.9%. The methodology presented is general enough to be applied for modeling other active beam units. Modeling of active beam units with Modelica. Available from: https...

  6. Design of active feedback controller used in the infrared beam line of SSRF

    International Nuclear Information System (INIS)

    Zhang Yongli; Tong Yajun; Zhang Zhaohong; Chen Min; Jiang Jianguo; Gong Peirong

    2014-01-01

    Background: The infrared beam line consists of many kinds of optical components that are susceptible to the external mechanical vibration, which will be further amplified by the long optical paths to seriously destroy the stability of infrared beam position. Purpose: The active feedback controller is used to stabilize the infrared beam position disturbed by the external environment. Methods: The design of the active feedback controller used in the infrared beam line of SSRF was proposed in this paper firstly, which included its background, light-path layout and operating process. Subsequently, the selections of the crucial components such as detector and actuator were discussed in details. Finally, the correction compensator design and its experimental test were also presented. The correction compensator design was realized by utilizing the frequency response method, and tested in time domain, frequency domain and mathematical model simulation of the controlled object. Results: The experimental tests included time domain step response signal of the controller, the time domain signal and its relevant magnitude spectrum in frequency domain due to the light source simulation vibration. Conclusion: The results show that the maximum effective operating band is 250 Hz and the maximum steady error is 5 μm. (authors)

  7. RESULTS FROM THE COMMISSIONING OF THE NSRL BEAM TRANSFER LINE AT BNL.

    Energy Technology Data Exchange (ETDEWEB)

    TSOUPAS,N.; BELLAVIA,S.; BONATI,R.; ET AL.

    2004-07-05

    The NASA SPACE RADIATION LABORATORY (NSRL) has been constructed and started operations at the Brookhaven National Laboratory in 2003. The NSRL facility will be used by NASA to perform radiation effect studies on materials and biological samples for the space program. The facility utilizes proton and heavy-ion beams of energies from 50 to 3000 MeVln which are accelerated by the AGS Booster synchrotron accelerator. To date, {sup 1}H, {sup 12}C, {sup 56}Fe, {sup 48}Ti, and {sup 197}Au ion beams of various magnetic rigidities have been extracted from the Booster, and transported by the NSRL beam transport line to the sample location which is located 100 m from the extraction point. The NSRL beam transport line has been designed to employ octupole magnetic elements which transform the normal (Gaussian) beam distribution at the location of the sample into a beam with rectangular cross section, and uniformly distributed over the sample. When using the octupole magnetic elements to obtain the uniform beam distribution on the sample, no beam-collimation is applied at any location along the NSRL beam transport line and the beam focusing on the sample is purely magnetic. The main subject of this paper will be the performance of the octupoles (third order optics) in obtaining uniform beam distributions at the target of the NSRL beam transport line.

  8. Experimental results from a diagnostic beam line for text

    International Nuclear Information System (INIS)

    Coupland, J.R.; Hammond, D.P.; Mepham, J.W.; Hancock, O.J.

    1987-01-01

    The experimental performance of a high brightness neutral beam system is described. The neutral beam serves as a diagnostic on the Fusion Research Center Tokamak TEXT, to measure impurities by observing optical spectra produced by collisions between the injected neutral beam and ions in the plasma

  9. High resolution line for secondary radioactive beams at the U400M cyclotron

    Science.gov (United States)

    Rodin, A. M.; Sidorchuk, S. I.; Stepantsov, S. V.; Ter-Akopian, G. M.; Fomichev, A. S.; Wolski, R.; Galinskiy, V. B.; Ivanov, G. N.; Ivanova, I. B.; Gorshkov, V. A.; Lavrentyev, A. Yu.; Oganessian, Yu. Ts.

    For implementation of an experimental program for studying nuclear reactions with radioactive ion beams in the energy domain of 20 through 80 MeV A the high resolution beam line ACCULINNA was put into commissioning on a primary beam line of the JINR U-400M cyclotron. By means of nuclear fragmentation of the 14N beam with the energy of 51 MeV A on the 170 mg/cm 2 carbon target radioactive beams of 6He, 8He and 8B were obtained. Possibilities of further development of the set-up are discussed.

  10. Development of pulsed MeV positron beam line

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Masaki; Kawasuso, Atsuo; Itoh, Hisayoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Masuno, Shinichi [Mitsubishi Electric Engineering Company Limited, Tokyo (Japan); Hirano, Takeshi; Kondo, Masakazu [Mitsubishi Electric Corporation, Tokyo (Japan); Okada, Sohei [Japan Atomic Energy Research Inst., Kashiwa, Chiba (Japan)

    2003-03-01

    We have developed a high-energy pulsed positron beam apparatus employing an RF acceleration method in order to apply positron annihilation lifetime spectroscopy (PALS) studies to bulk materials at high-temperature and/or high-pressure conditions. This apparatus contains a slow positron pulsing system and a radio frequency (RF) acceleration cavity. Performance tests were carried out using electron and positron beams. Beam energy ({approx}1 MeV), s beam size ({phi} 0.5 mm) and a beam transmission are as good as expectations of machine design. In the time structures of accelerated beam, satellite pulses superposed on broad pulses were observed. In order to make PULS measurement using RF cavity, it is important to form a high quality beam with single fine pulses by refine of the bunching system and the RF source driven with high duty ratio. (author)

  11. Reliability analysis of minimum energy on target for laser facilities with more beam lines

    International Nuclear Information System (INIS)

    Chen Guangyu

    2008-01-01

    Shot reliability performance measures of laser facilities with more beam lines pertain to three categories: minimum-energy-on-target, power balance, and shot diagnostics. Accounting for symmetry of NIF beam line design and similarity of subset reliability in a same partition, a fault tree of meeting minimum-energy-on-target for the large laser facility shot of type K and a simplified method are presented, which are used to analyze hypothetic reliability of partition subsets in order to get trends of influences increasing number of beam lines and diverse shot types of large laser facilities on their shot reliability. Finally, it finds that improving component reliability is more crucial for laser facilities with more beam lines in comparison with those with beam lines and functional diversity from design flexibility is greatly helpful for improving shot reliability. (authors)

  12. REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

    Energy Technology Data Exchange (ETDEWEB)

    FOERSTER,C.

    1999-05-01

    Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware

  13. REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B

    International Nuclear Information System (INIS)

    FOERSTER, C.

    1999-01-01

    Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of ∼ 1 x 10 -10 Torr without beam and ∼ 1 x 10 -9 Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware downstream of front ends. O-ring-sealed valves, if used, are not

  14. Monitoring beam position in the TRISTAN AR-to-MR transport lines

    International Nuclear Information System (INIS)

    Ieiri, Takao; Arinaga, Mitsuhiro

    1994-01-01

    A beam-position monitor (BPM) has been installed in the transport lines between the Accumulation Ring (AR) and the Main Ring (MR) of TRISTAN. This monitor can detect the beam position and its charge every passage of the beam. Variations of the beam position have been observed during the routine operation. An investigation into the AR extraction components has been carried out in order to clarify a source of the variations. (author)

  15. An after-market, five-port vertical beam line extension for the PETtrace

    DEFF Research Database (Denmark)

    Barnhart, T. E.; Engle, J. W.; Severin, Gregory

    2012-01-01

    Most commercial cyclotrons intended for medical isotope production provide a limited number of beam ports crowded into a minimal vault space. Taking advantage of our new lab construction, we planned and installed a beam-line on port ♯2 of our GEMS PETtrace to bring beam to an additional 5 target...... positions. These are oriented in the vertical plane, with the downward directed beam well suited for molten target substrates. © 2012 American Institute of Physics...

  16. An after-market, five-port vertical beam line extension for the PETtrace

    Science.gov (United States)

    Barnhart, T. E.; Engle, J. W.; Severin, G. W.; Valdovinos, H. F.; Gagnon, K.; Nickles, R. J.

    2012-12-01

    Most commercial cyclotrons intended for medical isotope production provide a limited number of beam ports crowded into a minimal vault space. Taking advantage of our new lab construction, we planned and installed a beam-line on port ♯2 of our GEMS PETtrace to bring beam to an additional 5 target positions. These are oriented in the vertical plane, with the downward directed beam well suited for molten target substrates.

  17. DIAGNOSIS OF THE LOW EMITTANCE BEAM IN ATF DR EXTRACTION LINE

    International Nuclear Information System (INIS)

    McCormick, Douglas

    2003-01-01

    The ATF (Accelerator Test Facility in KEK) damping ring has been designed to produce the low emittance beam required by future linear colliders. In the design, the normalized vertical emittance of the ATF damping ring is 3.0E-8 radm which corresponds to the vertical beam size of about 10 micron in the extraction line. The emittance of the beam extracted from the ATF damping ring is measured with four wire scanners located in a dispersion free region of the extraction line. The optics of the extraction line is also studied. We will report the method and the result of the emittance measurement at the extraction line

  18. IDENTIFIKASI PROFIL DASAR LAUT MENGGUNAKAN INSTRUMEN SIDE SCAN SONAR DENGAN METODE BEAM PATTERN DISCRETE-EQUI-SPACED UNSHADED LINE ARRAY

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-05-01

    Full Text Available Laut Punggur merupakan laut yang terletak di Batam, Kepulauan Riau yang mempunyai beragam habitat objek,dan bentuk struktur bawah laut yang memiliki dinamika laut yang sangat tinggi. Side scan sonar (SSS merupakan instrumen pengembangan sistem sonar yang mampu menunjukkan dalam gambar dua dimensional permukaan dasar laut dengan kondisi kontur, topografi, dan target secara bersamaan. Metode Beam Pattern Discrete-Equi-Spaced Unshaded Line Array digunakan untuk menghitung beam pattern dua dimensi yang tergantung pada sudut dari gelombang suara yang masuk dari sumbu array yang diterima tergantung pada sudut di mana sinar suara pada array. Penelitian ini dilakukan pada Desember 2016 di laut Punggur,Batam, Kepulauan Riau-Indonesia, dengan koordinat 104 ° 08,7102 E dan 1° 03,2448 N sampai 1 ° 03.3977 N dan 104 ° 08,8133 E, menggunakan instrumen Side Scan Sonar C-Max CM2 Tow fish dengan frekuensi 325 kHz. Hasil yang diperoleh dari perekaman terdapat 7 target, dan Beam pattern dari metode Beam Discrete-Equi-Spaced Unshaded Line Array target 4 memiliki nilai tertinggi pada directivity Pattern yaitu 21.08 dB. Hasil model beam pattern ini memiliki nilai pusat pada incidence angle (o terhadap Directivity pattern (dB tidak berada di nilai 0 ataupun pada pusat beam pattern yang dihasilkan pada target 6 dengan nilai incident angle -1.5 o dan 1.5o mengalami penurunan hingga -40 dB. Karakteristik sedimen dasar perairan di laut punggur ditemukan lebih banyak pasir. Hasil metode Beam Discrete-Equi-Spaced Unshaded Line Array ditemukan bangkai kapal tenggelam.Kata Kunci: Side Scan Sonar, Beam Pattern Discrete-Equi-Spaced Unshaded Line Array, Incidence angle, Directivity pattern IDENTIFICATION OF SEABED PROFILE USING SIDE SCAN SONAR INSTRUMENT WITH PATTERN DISCRETE-EQUI-SPACED UNSHADED LINE ARRAY METHODRiau Islands is an island that has a variety of habitat objects, and forms of submarine structures that have a very high ocean dynamics, Punggur Sea is the sea

  19. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Science.gov (United States)

    Zhang, Xu; Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming; Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN-LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  20. Proton induced radioactivity estimation and radiological safety aspects of materials science beam line at medical cyclotron

    International Nuclear Information System (INIS)

    Srivastava, S.K.; Nair, K.G.M.; Sarangapani, R.

    2012-01-01

    A medical cyclotron facility is under development in Kolkata. This medical cyclotron would deliver 15 - 30 MeV H + ions with beam current up to 500 μA. Though this facility will be mainly used for production of medically useful isotopes, a beam line has been also provided for materials science research. The materials science beam line will be used to study radiation damage in nuclear materials. Apart from radiation damage studies, material science beam line will be used for thin layer activation analysis, charged particle activation analysis and production of special isotopes. High intensity proton beam in this energy regime can induce high level of radioactivity in the target material and other beam line components. Hence it is necessary to calculate the induced radioactivity for a variety of materials, so as to find a suitable candidate for use in beam line components, to design radiation shielding and to design proper target handling devices and shielding arrangements. There are two ways by which radioactivity in beam line components can be induced, either by direct interaction of proton beam or by neutrons emitted from target during irradiation. The cross-section of production of various radionuclides and neutrons at different energies produced as a result of nuclear reaction between proton and target atoms has been generated using ALICE code. These cross-sections are used to calculate concentration of radionuclides and emitted neutron spectrum. The decay scheme of radionuclides is taken from Universal Nuclide Chart. Neutron induced activity in target chamber is estimated using MCNP code. These calculations have found to be very useful in the material selection for beam line components and designing radiation shielding. Various aspects of radioactivity calculations and radiological safety on material science beam line will be discussed. (author)

  1. Beam Transfer Line Design for a Plasma Wakefield Acceleration Experiment (AWAKE) at the CERN SPS

    CERN Document Server

    Bracco, C; Brethoux, D; Clerc, V; Goddard, B; Gschwendtner, E; Jensen, L K; Kosmicki, A; Le Godec, G; Meddahi, M; Muggli, P; Mutin, C; Osborne, O; Papastergiou, K; Pardons, A; Velotti, F M; Vincke, H

    2013-01-01

    The world’s first proton driven plasma wakefield acceleration experiment (AWAKE) is presently being studied at CERN. The experimentwill use a high energy proton beam extracted from the SPS as driver. Two possible locations for installing the AWAKE facility were considered: the West Area and the CNGS beam line. The previous transfer line from the SPS to the West Area was completely dismantled in 2005 and would need to be fully re-designed and re-built. For this option, geometric constraints for radiation protection reasons would limit the maximum proton beam energy to 300 GeV. The existing CNGS line could be used by applying only minor changes to the lattice for the final focusing and the interface between the proton beam and the laser, required for plasma ionisation and bunch-modulation seeding. The beam line design studies performed for the two options are presented.

  2. Simulations of LEIR Injection Line Beam Position Monitors

    CERN Document Server

    Maltseva, Mariya

    2016-01-01

    In this paper sensitivity characteristics of a beam position monitor are described. Characteristics are obtained during the simulations in CST Studio, the results are compared with the calculated values. The results for a low-beta beam and with a wire are compared.

  3. Development of beam position monitor of the transport line from LINAC to AR in TRISTAN

    International Nuclear Information System (INIS)

    Tejima, M.; Satoh, M.; Mori, K.

    1994-01-01

    We constructed and installed 9 Beam Position Monitors (BPM) having four strip-lines along the beam transport line from the linac to the accumulating ring (AR) last summer. Every signal was gathered in the local control room, the beam signal is measured by using the digitizing oscilloscope and sent to the micro-computer(μ-com) through the GPIB. The picture of beam positions on the μ-com terminal is converted to the video signal and transmitted to a TV monitor at the central control room. (author)

  4. The MICE Muon Beam on ISIS and the beam-line instrumentation of the Muon Ionization Cooling Experiment

    CERN Document Server

    Bogomilov, M.; Kolev, D.; Russinov, I.; Tsenov, R.; Vankova-Kirilova, G.; Wang, L.; Xu, F.Y.; Zheng, S.X.; Bertoni, R.; Bonesini, M.; Ferri, F.; Lucchini, G.; Mazza, R.; Paleari, F.; Strati, F.; Palladino, V.; Cecchet, G.; de Bari, A.; Capponi, M.; Cirillo, A.; Iaciofano, A.; Manfredini, A.; Parisi, M.; Orestano, D.; Pastore, F.; Tonazzo, A.; Tortora, L.; Mori, Y.; Kuno, Y.; Sakamoto, H.; Sato, A.; Yano, T.; Yoshida, M.; Ishimoto, S.; Suzuki, S.; Yoshimura, K.; Filthaut, F.; Garoby, R.; Gilardoni, S.; Gruber, P.; Hanke, K.; Haseroth, H.; Janot, P.; Lombardi, A.; Ramberger, S.; Vretenar, M.; Bene, P.; Blondel, A.; Cadoux, F.; Graulich, J.S.; Grichine, V.; Gschwendtner, E.; Masciocchi, F.; Sandstrom, R.; Verguilov, V.; Wisting, H.; Petitjean, C.; Seviour, R.; Alexander, J.; Charnley, G.; Collomb, N.; Griffiths, S.; Martlew, B.; Moss, A.; Mullacrane, I.; Oates, A.; Owens, P.; White, C.; York, S.; Adams, D.; Apsimon, R.; Barclay, P.; Baynham, D.E.; Bradshaw, T.W.; Courthold, M.; Drumm, P.; Edgecock, R.; Hayler, T.; Hills, M.; Ivaniouchenkov, Y.; Jones, A.; Lintern, A.; MacWaters, C.; Nelson, C.; Nichols, A.; Preece, R.; Ricciardi, S.; Rochford, J.H.; Rogers, C.; Spensley, W.; Tarrant, J.; Tilley, K.; Watson, S.; Wilson, A.; Forrest, D.; Soler, F.J.P.; Walaron, K.; Cooke, P.; Gamet, R.; Alekou, A.; Apollonio, M.; Barber, G.; Clark, D.; Clark, I.; Dobbs, A.; Dornan, P.; Fish, A.; Hare, R.; Greenwood, S.; Jamdagni, A.; Kasey, V.; Khaleeq, M.; Leaver, J.; Long, K.; McKigney, E.; Matsushita, T.; Pasternak, J.; Sashalmi, T.; Savidge, T.; Takahashi, M.; Blackmore, V.; Carlisle, T.; Cobb, J.H.; Lau, W.; Rayner, M.; Tunnell, C.D.; Witte, H.; Yang, S.; Booth, C.N.; Hodgson, P.; Howlett, L.; Nicholson, R.; Overton, E.; Robinson, M.; Smith, P.; Adey, D.; Back, J.; Boyd, S.; Harrison, P.; Ellis, M.; Kyberd, P.; Littlefield, M.; Nebrensky, J.J.; Bross, A.D.; Geer, S.; Neuffer, D.; Moretti, A.; Popovic, M.; Cummings, M.A.C.; Roberts, T.J.; DeMello, A.; Green, M.A.; Li, D.; Virostek, S.; Zisman, M.S.; Freemire, B.; Hanlet, P.; Huang, D.; Kafka, G.; Kaplan, D.M.; Snopok, P.; Torun, Y.; Blot, S.; Kim, Y.K.; Bravar, U.; Onel, Y.; Cline, D.; Fukui, Y.; Lee, K.; Yang, X.; Rimmer, R.A.; Cremaldi, L.M.; Gregoire, G.; Hart, T.L.; Sanders, D.A.; Summers, D.J.; Coney, L.; Fletcher, R.; Hanson, G.G.; Heidt, C.; Gallardo, J.; Kahn, S.; Kirk, H.; Palmer, R.B.

    2012-01-01

    The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz muon rate, with a neglible pion contamination in the beam.

  5. The MICE Muon Beam on ISIS and the beam-line instrumentation of the Muon Ionization Cooling Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bogomilov, M. [University of Sofia (Bulgaria); et al.

    2012-05-01

    The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz instantaneous muon rate, with a neglible pion contamination in the beam.

  6. Design study of low energy beam transport line for ion beams of the post-accelerator at RAON

    Science.gov (United States)

    Lee, Yumi; Kim, Eun-San

    2015-07-01

    Low-energy ions produced by the ion source pass through the focusing and acceleration sections. During this process, the ions accumulate energy and are finally transported to the apparatus that utilizes them for a specific purpose. Thus, in order to increase the transmission efficiency of the ion beams, the low energy beam transport (LEBT) system must minimize the beam loss and the emittance growth. The LEBT system is designed and optimized to transmit 132Sn16+ and 58Ni8+ beams of the post-accelerator at RAON that is the accelerator complex for the rare isotope science. The post-accelerator LEBT line comprises solenoids and electrostatic quadrupoles for transverse focusing and a multi-harmonic buncher for longitudinal focusing. This paper presents the results of the optical design and beam tracking for the post-accelerator LEBT obtained by using TraceWIN and TRACK codes.

  7. High intensity beam profile monitors for the LAMPF primary beam lines

    International Nuclear Information System (INIS)

    Hoffman, E.W.; Macek, R.J.; van Dyck, O.; Lee, D.; Harvey, A.; Bridge, J.; Cainet, J.

    1979-01-01

    Two types of beam profile monitors are in use at LAMPF to measure the properties of the 800 MeV, 500 μA proton beam external to the linac. Both types use secondary electron emission from a wire to produce a current signal proportional to the amount of proton beam that intercepts the wire. The wire scanner system uses a pair of orthogonal wires which are passed through the beam and the harp system uses two fixed planes of parallel wires. Most of the harps are not retractable and are exposed continuously to the primary beam. The high beam intensities available lead to a number of technical problems for instruments that intercept the beam or are close to primary beam targets. The thermal, electrical, radiation-damage, and material selection problems encountered, and some solutions which have been implemented are discussed

  8. The Brookhaven ATF low-emittance beam line

    International Nuclear Information System (INIS)

    Wang, X.J.; Kirk, H.G.

    1991-01-01

    One component of the experimental program at the Brookhaven Accelerator Test Facility (ATF) consists of a class of experiments which will study the acceleration of electrons through micron-size structures which are exposed in coincidence to a 100 GW CO 2 laser beam. These experiments require the development and control of an electron beam with geometric emittances on the order of 10 -10 m-rad and intensities on the order of 10 6 electrons. In this paper, the authors describe the strategies for producing such beams and the effects of higher-order aberrations. Particle tracking results are presented for the final-focus system

  9. NSLS infra-red beam line (U3) conceptual design report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, G.P.

    1984-02-09

    We describe the conceptual design of an infrared (I-R) beam line on the vacuum-ultra-violet storage ring of the National Synchrotron Light Source. The beam line forms part of the Phase II expansion of the NSLS. Consistent with the implementation of the current design is the extraction of hitherto wasted radiation and the establishment of a mezzanine floor or platform to make full use of the available headroom. This means that the I-R beam line, once established, does not interfere with any existing operations on the VUV floor.

  10. Optics calculations and beam line design for the JANNuS facility in Orsay

    Science.gov (United States)

    Chauvin, N.; Henry, S.; Flocard, H.; Fortuna, F.; Kaitasov, O.; Pariset, P.; Pellegrino, S.; Ruault, M. O.; Serruys, Y.; Trocelier, P.

    2007-08-01

    JANNuS (Joint Accelerators for Nano-Science and Nuclear Simulation) will be a unique user facility in Europe dedicated to material modification by ion beam implantation and irradiation. The main originality of the project is that it will be possible to perform implantation and irradiation with simultaneous multiple ions beams and in situ characterization by transmission electron microscopy (TEM) observation or ion beam analysis. This facility will be composed of two experimental platforms located in two sites: the CEA-SRMP in Saclay and the CNRS-CSNSM in Orsay. This paper will focus on the design of two new transport beam lines for the Orsay site. One of the most challenging parts of the JANNuS project (Orsay site) is to design two new beam lines in order to inject, into a 200 kV TEM, two different ion beams (low and medium energy) coming from two existing pieces of equipment: a 2 MV Tandem accelerator and a 190 kV ion implanter. For these new beam lines, first order beam calculations have been done using transfer matrix formalism. A genetic algorithm has been written and adapted to perform the optimization of the beam line parameters. Then, using the SIMION code, field maps of the electrostatic elements (quadrupoles, spherical sectors) have been calculated and ion trajectories have been simulated. We studied specifically the optical aberrations induced by the electrostatic spherical deflectors. Finally, the results of the first order calculations and the field map simulations show a good agreement.

  11. Design and initial tests of beam current monitoring systems for the APS transport lines

    International Nuclear Information System (INIS)

    Wang, Xucheng.

    1992-01-01

    The non-intercepting beam current monitoring systems suitable for a wide, range of beam parameters have been developed for the Advanced Photon Source (APS) low energy transport lines and high energy transport line. The positron or electron beam pulse in the transport lines wig have peak beam currents ranging from 8 mA to 29 A with pulse widths varying from 120 ps to 30 ns and pulse repetition rates from 2 Hz to 60 Hz. The peak beam current or total beam charge is measured with the fast or integrating current transformer, respectively, manufactured by Bergoz. In-house high speed beam signal processing electronics provide a DC level output proportional to the peak current or total charge for the digitizer input. The prototype systems were tested on the linacs which have beam pulse structures similar to that of the APS transport lines. This paper describes the design of beam signal processing electronics and grounding and shielding methods for current transformers. The results of the initial operations are presented. A short introduction on the preliminary design of current monitoring systems for the APS rings is also included

  12. Optics calculations and beam line design for the JANNuS facility in Orsay

    International Nuclear Information System (INIS)

    Chauvin, N.; Henry, S.; Flocard, H.; Fortuna, F.; Kaitasov, O.; Pariset, P.; Pellegrino, S.; Ruault, M.O.; Serruys, Y.; Trocelier, P.

    2007-01-01

    JANNuS (Joint Accelerators for Nano-Science and Nuclear Simulation) will be a unique user facility in Europe dedicated to material modification by ion beam implantation and irradiation. The main originality of the project is that it will be possible to perform implantation and irradiation with simultaneous multiple ions beams and in situ characterization by transmission electron microscopy (TEM) observation or ion beam analysis. This facility will be composed of two experimental platforms located in two sites: the CEA-SRMP in Saclay and the CNRS-CSNSM in Orsay. This paper will focus on the design of two new transport beam lines for the Orsay site. One of the most challenging parts of the JANNuS project (Orsay site) is to design two new beam lines in order to inject, into a 200 kV TEM, two different ion beams (low and medium energy) coming from two existing pieces of equipment: a 2 MV Tandem accelerator and a 190 kV ion implanter. For these new beam lines, first order beam calculations have been done using transfer matrix formalism. A genetic algorithm has been written and adapted to perform the optimization of the beam line parameters. Then, using the SIMION code, field maps of the electrostatic elements (quadrupoles, spherical sectors) have been calculated and ion trajectories have been simulated. We studied specifically the optical aberrations induced by the electrostatic spherical deflectors. Finally, the results of the first order calculations and the field map simulations show a good agreement

  13. Pulsed magnet systems for high energy physics beam lines

    International Nuclear Information System (INIS)

    Praeg, W.F.

    1975-01-01

    During the past years pulsed magnet systems have been developed at Argonne National Laboratory to transport beam bursts of charged high energy particles of the Zero Gradient Synchrotron (ZGS) facility. The particular features of the switching circuits, the power supplies and the magnets are described. Included are septum, quadrupole, beam shutter and bending magnets with energies ranging from 25 J to 100 kJ. The degree to which magnet current must be repeated and held constant (flattopped) during beam spill varies from +-5 percent for a beam shutter magnet to +-0.005 percent for a bending magnet; the duration of flattop ranges from a few μs to many ms. (U.S.)

  14. Beam Line Design and Beam Physics Study of Energy Recovery Linac Free Electron Laser at Peking University

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guimei [Peking Univ., Beijing (China)

    2011-12-31

    Energy recovering linac (ERL) offers an attractive alternative for generating intense beams of charged particles by approaching the operational efficiency of a storage ring while maintaining the superior beam quality typical of a linear accelerator. In ERLs, the decelerated beam cancels the beam loading effects of the accelerated beam with high repetition rate. Therefore, ERLs can, in principle, accelerate very high average currents with only modest amounts of RF power. So the efficiency of RF power to beam is much higher. Furthermore, the energy of beam to dump is lower, so it will reduce dump radiation. With the successful experiments in large maximum-to-injection energy ratio up to 51:1 and high power FEL up to 14kW, the use of ERL, especially combining with superconducting RF technology, provides a potentially powerful new paradigm for generation of the charged particle beams used in MW FEL, synchrotron radiation sources, high-energy electron cooling devices and so on. The 3+1/2 DC-SC photo injector and two 9cell TESLA superconducting cavity for IR SASE FEL in PKU provides a good platform to achieve high average FEL with Energy Recovery. The work of this thesis is on Beam line design and Beam dynamics study of Energy Recovery Linac Free Electron Laser for Peking University. It is the upgrade of PKU facility, which is under construction. With ERL, this facility can work in CW mode, so it can operate high average beam current without RF power constraint in main linac and generate high average FEL power. Moreover, it provides a test facility to study the key technology in ERL. System parameters are optimized for PKU ERL-FEL. The oscillation FEL output power is studied with different bunch charge, transverse emittance, bunch length and energy spread. The theory of optimal RF power and Q{sub ext} with ERL and without ERL is analyzed and applied to PKU injector and linac including microphonic effect. pace charge effect in the injector and merger is studied for beam

  15. Transport and dosimetric solutions for the ELIMED laser-driven beam line

    International Nuclear Information System (INIS)

    Cirrone, G.A.P.; Romano, F.; Scuderi, V.; Amato, A.; Candiano, G.; Cuttone, G.; Giove, D.; Korn, G.; Krasa, J.; Leanza, R.; Manna, R.; Maggiore, M.; Marchese, V.; Margarone, D.; Milluzzo, G.; Petringa, G.; Sabini, M.G.; Schillaci, F.

    2015-01-01

    Within 2017, the ELIMED (ELI-Beamlines MEDical applications) transport beam-line and dosimetric systems for laser-generated beams will be installed at the ELI-Beamlines facility in Prague (CZ), inside the ELIMAIA (ELI Multidisciplinary Applications of laser–Ion Acceleration) interaction room. The beam-line will be composed of two sections: one in vacuum, devoted to the collecting, focusing and energy selection of the primary beam and the second in air, where the ELIMED beam-line dosimetric devices will be located. This paper briefly describes the transport solutions that will be adopted together with the main dosimetric approaches. In particular, the description of an innovative Faraday Cup detector with its preliminary experimental tests will be reported

  16. Operational experience with synchrotron light interferometers for CEBAF experimental beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov

    2006-10-24

    Beam size and energy spread monitoring systems based on Synchrotron Light Interferometers (SLI) have been in operations at Jefferson Lab for several years. A non-invasive nature and a very high (a few mm) resolution of SLI make these instruments valuable beam diagnostic tools for the CEBAF accelerator. This presentation describes the evolution of the Synchrotron Light Interferometer at Jefferson Lab and highlights our extensive experience in the installation and operation of the SLI for CEBAF experimental beam lines.

  17. Object-Oriented Modelling of Flexible Beams

    International Nuclear Information System (INIS)

    Schiavo, Francesco; Vigano, Luca; Ferretti, Gianni

    2006-01-01

    In this paper the problem of modelling flexible thin beams in multibody systems is tackled. The proposed model, implemented with the object-oriented modelling language Modelica, is completely modular, allowing the realization of complex systems by simple aggregation of basic components. The finite element method is employed as the basic scheme to spatially discretize the model equations. Exploiting the modular features of the language, the beam substructuring discretisation scheme (mixed finite element-finite volume) is derived as well. Selected simulation results are presented in order to validate the model with respect to both theoretical predictions and literature reference results

  18. Spectral line competition in a coaxial e-beam pumped high pressure Ar/Xe laser

    NARCIS (Netherlands)

    Lan, Y.F.; Lan, Y.F.; Peters, P.J.M.; Witteman, W.J.

    1991-01-01

    In order to study the kinetic mechanism of the e-beam pumped Ar/Xe laser, the temporal profiles of individual laser lines during multiline oscillation have been measured as a function of power deposition (1–12MW/cm3) and gas laser pressure (2–14 bar) using a short pulse (30 ns) coaxial electron beam

  19. Design of medium energy beam transport line between the RFQ and ...

    Indian Academy of Sciences (India)

    Abstract. The design of a medium energy beam transport (MEBT) line comprising of a re-buncher and four quadrupoles, two upstream and the other two downstream of the re-buncher, has been presented. The design was done to ensure almost 100% transport of heavy-ion beams of about 99 keV/u energy from RFQ having ...

  20. Design of medium energy beam transport line between the RFQ and ...

    Indian Academy of Sciences (India)

    Design of medium energy beam transport line between the RFQ and the Linac in the radioactive ion beam facility at VECC, Kolkata. S Dechoudhury Vaishali Naik Manas Mondal Hemendra Kumar Pandey Avik Chatterjee Dirtha Sanyal Debasis Bhowmick Alok Chakrabarti. Research Articles Volume 75 Issue 3 September ...

  1. Beam profile control of line focus for x-ray laser experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, G.Y.; Jitsuno, T.; Nakatsuka, M.; Daido, H.; Kato, Y.; Nakai, S. [Osaka Univ., Suita, Osaka (Japan). Inst. of Laser Engineering

    1995-12-31

    A high aspect ratio line focus on a target for the x-ray laser experiments is required for obtaining a high gain-length product. A new line focus system is developed to generate a uniform line focus. The system consists of a deformable mirror of a continuous faceplate type which provides an appropriate wavefront distribution for compensating an aberration of a line focus optics. The width and intensity distribution of 18.2mm long line focus have been improved on 2 times diffraction limit. As other application, a rectangular beam shaping from a circular defocused beam is investigated by the experiment and the diffraction calculation. The controllability of intensity distribution of laser beam by deformable mirror has been demonstrated.

  2. Interleaving of beam lines inside the PS tunnel

    CERN Multimedia

    1983-01-01

    View against the direction of the proton beams. The PS ring (section 26) is on the left. The injection tunnel for LEAR leaving from here has increased the trafic in this already busy area where the two Linacs and the transfer tunnel leading to the SPS, ISR and AA join the PS ring (cf. photo 7802260, 7802261, Annual Report 1981, p. 89, fig. 12).

  3. Beam lines from Linac 1 and Linac 2 to the Booster

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    View against the direction of the beams. Both Linacs are behind the concrete wall at the back of the picture. The 50 MeV proton beam from Linac 1 enters the PS tunnel through the hole at left. The line from Linac 2, in the process of being installed, comes from the hole at right. The lines converge at a switching magnet (prominently in the foreground), which selects which of the 2 beams to send on to the Booster. See also 7802261 and further explanations there.

  4. Analysis of particle species evolution in neutral-beam injection lines

    International Nuclear Information System (INIS)

    Kim, J.; Haselton, H.H.

    1979-01-01

    Analytic solutions to the rate equations describing the species evolution of a multispecies positive ion beam of hydrogen due to charge exchange and molecular dissociation are derived as a function of the background gas (H 2 ) line density in the neutralizing gas cell and in the drift tube. Using the solutions, calculations are presented for the relative abundance of each species as a function of the gas-cell thickness, the reionization loss in the drift tube, and the neutral-beam power as a function of the beam energy and the species composition of the original ion beam

  5. Emittance Measurements For Future LHC Beams Using The PS Booster Measurement Line

    CERN Document Server

    Abelleira, Jose; Mikulec, Bettina; Di Giovanni, Gian Piero; CERN. Geneva. ATS Department

    2017-01-01

    The CERN PS Booster measurement line contains three pairs of SEM grids separated by drift space that measures the beam size in both planes. The combined analysis of these grids allows calculating a value for the transverse beam emittances. The precision of such a measurement depends on the ratio of RMS beam size and wire spacing. Within the LIU-PSB upgrade the extraction kinetic energy of the PSB will be increased from the current 1.4 GeV to 2.0 GeV. This will result in smaller transverse beam sizes for some of the future beams. The present layout of the transverse emittance measurement line is reviewed to verify if it will satisfy future requirements.

  6. Defocusing beam line design for an irradiation facility at the TAEA SANAEM Proton Accelerator Facility

    CERN Document Server

    Gencer, A.; Efthymiopoulos, I.; Yiğitoğlu, M.

    2016-01-01

    Electronic components must be tested to ensure reliable performance in high radiation environments such as Hi-Limu LHC and space. We propose a defocusing beam line to perform proton irradiation tests in Turkey. The Turkish Atomic Energy Authority SANAEM Proton Accelerator Facility was inaugurated in May 2012 for radioisotope production. The facility has also an R&D room for research purposes. The accelerator produces protons with 30 MeV kinetic energy and the beam current is variable between View the MathML source10μA and View the MathML source1.2mA. The beam kinetic energy is suitable for irradiation tests, however the beam current is high and therefore the flux must be lowered. We plan to build a defocusing beam line (DBL) in order to enlarge the beam size, reduce the flux to match the required specifications for the irradiation tests. Current design includes the beam transport and the final focusing magnets to blow up the beam. Scattering foils and a collimator is placed for the reduction of the beam ...

  7. Beam Line and Associated Work: Operational Phase 1985-1987

    Science.gov (United States)

    1988-08-26

    ENEA FEL experiment. F. Cicci, E. Fiorentino. A. Ranieri, E. Sabie. Centro Ricerche Energia Frascati (Italy?. ....................... 169 582.25...C) knife-edge pinhole bracket (cf. Fig. 14); (D) beam stop; (E) calorimeter with an attached Si solar cell detector; (F) paddle with tilted platforms...used for T real-time signal pickup behind the slit was a standard Si solar cell, epoxied to the calorimeter case (detail . in Fig. 5). The experimental

  8. Uniform beam distributions at the target of the NASA Space Radiation Laboratory’s beam line

    Directory of Open Access Journals (Sweden)

    N. Tsoupas

    2007-02-01

    Full Text Available Errors in delivering a uniformly distributed radiation dose to biological and material samples exposed to charged particle beams are a significant problem for experimenters. In this paper, we discuss data collected on the uniform beam distributions produced for NASA’s Space Radiation Laboratory (NSRL at Brookhaven National Laboratory (BNL, using a method that was conceived theoretically and tested experimentally at BNL. This method [N. Tsoupas et al., Nucl. Sci. Eng. 126, 71 (1997NSENAO0029-5639] of generating uniform beam distributions on a plane normal to the beam’s direction relies only on magnetically focusing the transported beam; no collimation of the beam is required or any other type of interaction of the beam with materials other than the target material. The method compares favorably with alternative methods of producing such distributions, and it can be applied to the entire energy spectrum of charged particle beams that are delivered to the NSRL’s experiments by the Booster for the Alternating Gradient Synchrotron at BNL.

  9. Accurate transfer maps for realistic beam-line elements: Straight elements

    Directory of Open Access Journals (Sweden)

    Chad E. Mitchell

    2010-06-01

    Full Text Available The behavior of orbits in charged-particle beam transport systems, including both linear and circular accelerators as well as final focus sections and spectrometers, can depend sensitively on nonlinear fringe-field and high-order-multipole effects in the various beam-line elements. The inclusion of these effects requires a detailed and realistic model of the interior and fringe fields, including their high spatial derivatives. A collection of surface fitting methods has been developed for extracting this information accurately from three-dimensional field data on a grid, as provided by various three-dimensional finite-element field codes. Based on these realistic field models, Lie or other methods may be used to compute accurate design orbits and accurate transfer maps about these orbits. Part I of this work presents a treatment of straight-axis magnetic elements, while part II will treat bending dipoles with large sagitta. An exactly soluble but numerically challenging model field is used to provide a rigorous collection of performance benchmarks.

  10. Fast pencil beam dose calculation for proton therapy using a double-Gaussian beam model

    Directory of Open Access Journals (Sweden)

    Joakim eda Silva

    2015-12-01

    Full Text Available The highly conformal dose distributions produced by scanned proton pencil beams are more sensitive to motion and anatomical changes than those produced by conventional radiotherapy. The ability to calculate the dose in real time as it is being delivered would enable, for example, online dose monitoring, and is therefore highly desirable. We have previously described an implementation of a pencil beam algorithm running on graphics processing units (GPUs intended specifically for online dose calculation. Here we present an extension to the dose calculation engine employing a double-Gaussian beam model to better account for the low-dose halo. To the best of our knowledge, it is the first such pencil beam algorithm for proton therapy running on a GPU. We employ two different parametrizations for the halo dose, one describing the distribution of secondary particles from nuclear interactions found in the literature and one relying on directly fitting the model to Monte Carlo simulations of pencil beams in water. Despite the large width of the halo contribution, we show how in either case the second Gaussian can be included whilst prolonging the calculation of the investigated plans by no more than 16%, or the calculation of the most time-consuming energy layers by about 25%. Further, the calculation time is relatively unaffected by the parametrization used, which suggests that these results should hold also for different systems. Finally, since the implementation is based on an algorithm employed by a commercial treatment planning system, it is expected that with adequate tuning, it should be able to reproduce the halo dose from a general beam line with sufficient accuracy.

  11. Chemical investigations of isotope separation on line target units for carbon and nitrogen beams

    CERN Document Server

    Franberg, H; Gäggeler, H W; Köster, U

    2006-01-01

    Radioactive ion beams (RIBs) are of significant interest in a number of applications. Isotope separation on line (ISOL) facilities provide RIB with high beam intensities and good beam quality. An atom that is produced within the ISOL target will first diffuse out from the target material. During the effusion towards the transfer line and into the ion source the many contacts with the surrounding surfaces may cause unacceptable delays in the transport and, hence, losses of the shorter-lived isotopes. We performed systematic chemical investigations of adsorption in a temperature and concentration regime relevant for ISOL targets and ion source units, with regard to CO/sub x/ and NOmaterials are potential construction materials for the above-mentioned areas. Off-line and on-line tests have been performed using a gas thermochromatography setup with radioactive tracers. The experiments were performed at the production of tracers for atmospheric chemistry (PROTRAC) facility at the Paul Schener Institute in Villigen...

  12. Design of back-streaming white neutron beam line at CSNS.

    Science.gov (United States)

    Zhang, L Y; Jing, H T; Tang, J Y; Li, Q; Ruan, X C; Ren, J; Ning, C J; Yu, Y J; Tan, Z X; Wang, P C; He, Y C; Wang, X Q

    2018-02-01

    A white neutron beam line using back-streaming neutrons from the spallation target is under construction at China Spallation Neutron Source (CSNS). Different spectrometers, to be installed in the so-called Back-n beam line for nuclear data measurements, are also being developed in phases. The physical design of the beam line is carried out with the help of a complicated collimation system and a sophisticated neutron dump, taking the overview of the neutron beam characteristics into account. This includes energy spectrum, flux and time structure, the optimizations of neutron beam spots and in-hall background. The wide neutron energy range of 1eV-100MeV is excellent for supporting different applications, especially nuclear data measurements. At Endstation#2, which is about 80m away from the target, the main properties of the beam line include neutron flux of 10 6 n/cm 2 /s, time resolution of a few per mille over nearly the entire energy range, and in-hall background of about 0.01/cm 2 /s for both neutron and gamma. With its first commission in late 2017, Back-n will not only be the first high-performance white neutron source in China, but also one of the best white neutron sources in the world. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. The Challenge of Interfacing the Primary Beam Lines for the AWAKE Project at CERN

    CERN Document Server

    Bracco, C; Gschwendtner, E; Meddahi, M; Petrenko, A; Velotti, FM

    2014-01-01

    The Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) at CERN foresees the simultaneous operation of a proton, a laser and an electron beam. The first stage of the experiment will consist in proving the self-modulation, in the plasma, of a long proton bunch into micro-bunches. The success of this experiment requires an almost perfect concentricity of the proton and laser beam, over the full length of the plasma cell. The complexity of integrating the laser into the proton beam line and fulfilling the strict requirements in terms of pointing precision of the proton beam at the plasma cell are described. The second stage of the experiment foresees also the injection of electron bunches to probe the accelerating wakefields driven by the proton beam. Studies were performed to evaluate the possibility of injecting the electron beam parallel and with an offset to the beam axis. This option would imply that protons and electrons will have to share the last few meters of a common beam line. Issues and po...

  14. The use of EXOGAM for in-beam spectroscopy of proton drip-line nuclei with radioactive ion beams

    Science.gov (United States)

    Petri, M.; Paul, E. S.; Nolan, P. J.; Boston, A. J.; Boston, H. C.; Cooper, R. J.; Dimmock, M. R.; Gros, S.; McGuirk, B. M.; Turk, G.; Guinet, D.; Lautesse, Ph.; Meyer, M.; Redon, N.; Rossé, B.; Schmitt, Ch.; Stézowski, O.; Bhattacharyya, S.; De France, G.; Mukherjee, G.; Rejmund, F.; Savajols, H.; Scheurer, J. N.; Gál, J.; Molnár, J.; Nyakó, B. M.; Timár, J.; Zolnai, L.; Juhász, K.; Astier, A.; Deloncle, I.; Porquet, M. G.; Prévost, A.; Pucknell, V. F. E.; Wadsworth, R.; Joshi, P.; La Rana, G.; Moro, R.; Trotta, M.; Vardaci, E.; Hackman, G.; Ball, G. C.

    2009-08-01

    One of the first fusion-evaporation experiments using radioactive ion beams was performed at GANIL in order to study proton-rich nuclei of the light rare-earth region. The low production cross-section of the exotic species of interest, in combination with the low intensity of the beam and its induced background, demanded the use of a highly efficient experimental setup. This consisted of the EXOGAM γ-ray spectrometer coupled for the first time with both the DIAMANT charged-particle array and the VAMOS recoil spectrometer. In this report the experimental challenges of such studies will be discussed and the experimental achievements of the in-beam spectroscopy of proton drip-line nuclei using EXOGAM will be presented.

  15. DOE/DMS workshop on future synchrotron VUV and x-ray beam Lines

    International Nuclear Information System (INIS)

    Green, P.H.

    1992-03-01

    This document contains an overview of the participating DOE Laboratory beam line interests and the projected science to be addressed on these beam lines, both at new and existing synchrotron facilities. The scientific programs associated with present and planned synchrotron research by DOE Laboratories are discussed in chapters titled ''VUV and Soft X-Ray Research'' and ''Hard X-Ray Research.'' This research encompasses a broad range of the nation's scientific and technical research needs from fundamental to applied, in areas including environmental, biological, and physical sciences; new materials; and energy-related technologies. The projected cost of this proposed construction has been provided in tabular form using a uniform format so that anticipated DOE and outside funding agency contributions for construction and for research and development can be determined. The cost figures are, of course, subject to uncertainties of detailed design requirements and the availability of facility-designed generic components and outside vendors. The report also contains a compendium (as submitted by the beam line proposers) of the design capabilities, the anticipated costs, and the scientific programs of projected beam line construction at the four synchrotron facilities. A summary of the projected cost of these beam lines to be requested of DOE is compiled

  16. Controlling FAMA by the Ptolemy II model of ion beam transport

    Energy Technology Data Exchange (ETDEWEB)

    Balvanovic, R. [Vinca Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia)], E-mail: broman@vinca.rs; Radenovic, B. [Institute of Physics, Pregrevica 118, Belgrade 11080 (Serbia); Belicev, P.; Neskovic, N. [Vinca Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001 (Serbia)

    2009-08-11

    FAMA is a facility for modification and analysis of materials with ion beams. Due to the wide range of ion beams and energies used in the facility and its future expansion, the need has arisen for faster tuning of ion beams transport control parameters. With this aim, a new approach to modeling ion-beam transport system was developed, based on the Ptolemy II modeling and design framework. A model in Ptolemy II is a hierarchical aggregation of components called actors, which communicate with other actors using tokens, or pieces of data. Each ion optical element is modeled by a composite actor implementing beam matrix transformation function, while tokens carry beam matrix data. A basic library of models of typical ion optical elements is developed, and a complex model of FAMA ion beam transport system is hierarchically integrated with bottom-up approach. The model is extended to include control functions. The developed model is modular, flexible and extensible. The results obtained by simulation on the model demonstrate easy and efficient tuning of beam line control parameters. Fine tuning of control parameters, due to uncertainties inherent to modeling, still has to be performed on-line.

  17. Low emittance growth in a low energy beam transport line with un-neutralized section

    Science.gov (United States)

    Prost, L.; Carneiro, J.-P.; Shemyakin, A.

    2018-02-01

    In a low energy beam transport line (LEBT), the emittance growth due to the beam's space charge is typically suppressed by way of neutralization from either electrons or ions, which originate from ionization of the background gas. In cases where the beam is chopped, the neutralization pattern usually changes throughout the beginning of the pulse, causing the Twiss parameters to differ significantly from their steady state values, which, in turn, may result in beam losses downstream. For a modest beam perveance, there is an alternative solution, in which the beam is kept un-neutralized in the portion of the LEBT that contains the chopper. The emittance can be nearly preserved if the transition to the un-neutralized section occurs where the beam exhibits low transverse tails. This report introduces the rationale for the proposed scheme and formulates the physical arguments for it as well as its limitations. An experimental realization of the scheme was carried out at Fermilab's PIP2IT where low beam emittance dilution was demonstrated for a 5 mA, 30 keV H- beam.

  18. 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

  19. On-line Observation Of Electron Beam Bunches In The Large Storage Ring Of Kurchatov Srs

    CERN Document Server

    Ioudin, L I; Krylov, Y V; Rezvov, V A; Stirin, A I; Valentinov, A G; Yupinov, Y L

    2004-01-01

    A complex of instrumentation for visual quantitative estimation of electron beam bunches in the big storage ring of Kurchatov Synchrotron Radiation Centre (KSRC) is tested. The bunches pass through a cylindrical electrostatic sensor whose signal is recorded by a wide-band oscillograph. The TV camera reads the optical image of the signal from the oscillograph screen. The TV signal numbering board inputs the video image to the computer memory. The monitor displays the beam bunch structure. A special program provides on-line visualisation of bunch behaviour on the beam orbit. The images of beam structure and a series of images showing the beam behaviour in the regimes of accumulation, acceleration and in the stationary regime a full power are numbered and stored.

  20. Successful beam test of the SPS-to-LHC transfer line TI2

    CERN Multimedia

    2007-01-01

    Image of the first beam spot on the last BTV screen traversed by the beam during the TI 2 test.At 12:03:47 on 28 October a beam passed down the 2.7 km of the new SPS-to-LHC transfer line TI 2 at the first attempt, to within some 50 m of the LHC tunnel. After initial tuning, a range of measurements was carried out with a low intensity proton beam and preliminary analyses look good. After the test, no increase in radiation levels was found in either the LHC or ALICE, and the zones were rapidly opened again for access. As from next year TI 2 will regularly transport a beam from the SPS to the LHC injection point of Ring 1, near Point 2 (ALICE). The TI 8 transfer line, which will bring particles from the SPS to the injection point in Ring 2, near Point 8 (LHCb), was commissioned successfully with low intensity beam in 2004. The two LHC injection lines have a combined length of 5.6 km and comprise some seven hundred warm magnets. While a...

  1. Simulation and measurement of the electrostatic beam kicker in the low-energy undulator test line

    International Nuclear Information System (INIS)

    Waldschmidt, G. J.

    1998-01-01

    An electrostatic kicker has been constructed for use in the Low-Energy Undulator Test Line (LEUTL) at the Advanced Photon Source (APS). The function of the kicker is to limit the amount of beam current to be accelerated by the APS linac. Two electrodes within the kicker create an electric field that adjusts the trajectory of the beam. This paper will explore the static fields that are set up between the offset electrode plates and determine the reaction of the beam to this field. The kicker was numerically simulated using the electromagnetic solver package MAFIA [1

  2. Neutron beam line design of a white neutron source at CSNS

    Science.gov (United States)

    Jing, Hantao; Zhang, Liying; Tang, Jingyu; Ruan, Xichao; Ning, Changjun; Yu, Yongji; Wang, Pengcheng; Li, Qiang; Ren, Jie; Tang, Hongqing; Wang, Xiangqi

    2017-09-01

    China Spallation Neutron Source (CSNS), which is under construction, is a large scientific facility dedicated mainly for multi-disciplinary research on material characterization using neutron scattering techniques. The CSNS Phase-I accelerator will deliver a proton beam with an energy of 1.6 GeV and a pulse repetition rate of 25 Hz to a tungsten target, and the beam power is 100 kW. A white neutron source using the back-streaming neutrons through the incoming proton beam channel was proposed and is under construction. The back-streaming neutrons which are very intense and have good time structure are very suitable for nuclear data measurements. The white neutron source includes an 80-m neutron beam line, two experimental halls, and also six different types of spectrometers. The physics design of the beam line is presented in this paper, which includes beam optics and beam characterization simulations, with the emphasis on obtaining extremely low background. The first-batch experiments on nuclear data measurements are expected to be conducted in late 2017.

  3. Present Status And First Results of the Final Focus Beam Line at the KEK Accelerator Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Bambade, P.; /Orsay /KEK, Tsukuba; Alabau Pons, M.; /Valencia U., IFIC; Amann, J.; /SLAC; Angal-Kalinin, D.; /Daresbury; Apsimon, R.; /Oxford U., JAI; Araki, S.; Aryshev, A.; /KEK, Tsukuba; Bai, S.; /Beijing, Inst. High Energy Phys.; Bellomo, P.; /SLAC; Bett, D.; /Oxford U., JAI; Blair, G.; /Royal Holloway, U. of London; Bolzon, B.; /Savoie U.; Boogert, S.; Boorman, G.; /Royal Holloway, U. of London; Burrows, P.N.; Christian, G.; Coe, P.; Constance, B.; /Oxford U., JAI; Delahaye, Jean-Pierre; /CERN; Deacon, L.; /Royal Holloway, U. of London; Elsen, E.; /DESY /Valencia U., IFIC /KEK, Tsukuba /Beijing, Inst. High Energy Phys. /Savoie U. /Fermilab /Ecole Polytechnique /KEK, Tsukuba /Kyungpook Natl. U. /KEK, Tsukuba /Pohang Accelerator Lab. /Kyoto U., Inst. Chem. Res. /Savoie U. /Daresbury /Tokyo U. /Royal Holloway, U. of London /Kyungpook Natl. U. /Pohang Accelerator Lab. /Tokyo U. /KEK, Tsukuba /SLAC /University Coll. London /KEK, Tsukuba /SLAC /Royal Holloway, U. of London /KEK, Tsukuba /Tokyo U. /SLAC /Tohoku U. /KEK, Tsukuba /Tokyo U. /Pohang Accelerator Lab. /Brookhaven /SLAC /Oxford U., JAI /SLAC /Orsay /KEK, Tsukuba /Oxford U., JAI /Orsay /Fermilab /Tohoku U. /Manchester U. /CERN /SLAC /Tokyo U. /KEK, Tsukuba /Oxford U., JAI /Hiroshima U. /KEK, Tsukuba /CERN /KEK, Tsukuba /Oxford U., JAI /Ecole Polytechnique /SLAC /Oxford U., JAI /Fermilab /SLAC /Liverpool U. /SLAC /Tokyo U. /SLAC /Tokyo U. /KEK, Tsukuba /SLAC /CERN

    2011-11-11

    ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.

  4. Timoshenko beam model for chiral materials

    Science.gov (United States)

    Ma, T. Y.; Wang, Y. N.; Yuan, L.; Wang, J. S.; Qin, Q. H.

    2017-12-01

    Natural and artificial chiral materials such as deoxyribonucleic acid (DNA), chromatin fibers, flagellar filaments, chiral nanotubes, and chiral lattice materials widely exist. Due to the chirality of intricately helical or twisted microstructures, such materials hold great promise for use in diverse applications in smart sensors and actuators, force probes in biomedical engineering, structural elements for absorption of microwaves and elastic waves, etc. In this paper, a Timoshenko beam model for chiral materials is developed based on noncentrosymmetric micropolar elasticity theory. The governing equations and boundary conditions for a chiral beam problem are derived using the variational method and Hamilton's principle. The static bending and free vibration problem of a chiral beam are investigated using the proposed model. It is found that chirality can significantly affect the mechanical behavior of beams, making materials more flexible compared with nonchiral counterparts, inducing coupled twisting deformation, relatively larger deflection, and lower natural frequency. This study is helpful not only for understanding the mechanical behavior of chiral materials such as DNA and chromatin fibers and characterizing their mechanical properties, but also for the design of hierarchically structured chiral materials.

  5. Assembly line performance and modeling

    Science.gov (United States)

    Rane, Arun B.; Sunnapwar, Vivek K.

    2017-09-01

    Automobile sector forms the backbone of manufacturing sector. Vehicle assembly line is important section in automobile plant where repetitive tasks are performed one after another at different workstations. In this thesis, a methodology is proposed to reduce cycle time and time loss due to important factors like equipment failure, shortage of inventory, absenteeism, set-up, material handling, rejection and fatigue to improve output within given cost constraints. Various relationships between these factors, corresponding cost and output are established by scientific approach. This methodology is validated in three different vehicle assembly plants. Proposed methodology may help practitioners to optimize the assembly line using lean techniques.

  6. Design of the low energy beam transport line between CARIBU and the EBIS charge breeder

    Energy Technology Data Exchange (ETDEWEB)

    Perry, A., E-mail: aperry4@hawk.iit.edu [Argonne National Laboratory, Argonne, IL 60439, USA and Illinois Institute of Technology, Chicago, IL 60616 (United States); Ostroumov, P. N.; Barcikowski, A.; Dickerson, C.; Kondrashev, S. A.; Mustapha, B.; Savard, G. [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2015-01-09

    An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at ATLAS. The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and improve the purity of reaccelerated radioactive ion beams. The EBIS-CB is in the final stage of off-line commissioning. Currently, we are developing a low energy beam transport (LEBT) system to transfer CARIBU beams to the EBIS-CB. As was originally planned, an RFQ cooler-buncher will precede the EBIS-CB. Recently, it was decided to include a multi-reflection time-of-flight (MR-TOF) mass-spectrometer following the RFQ. MR-TOF is a relatively new technology used to purify beams with a mass-resolving power up to 3×10{sup 5} as was demonstrated in experiments at CERN/ISOLDE. Very high purity singly-charged radioactive ion beams will be injected into the EBIS for charge breeding and due to its inherent properties, the EBIS-CB will maintain the purity of the charge bred beams. Possible contamination of residual gas ions will be greatly suppressed by achieving ultra-high vacuum in the EBIS trap. This paper will present and discuss the design of the LEBT and the overall integration of the EBIS-CB into ATLAS.

  7. Upgrades to the SPS-to-LHC Transfer Line Beam Stoppers for the LHC High-Luminosity Era

    CERN Document Server

    Kain, Verena; Fraser, Matthew; Goddard, Brennan; Meddahi, Malika; Perillo Marcone, Antonio; Steele, Genevieve; Velotti, Francesco

    2016-01-01

    Each of the 3 km long transfer lines between the SPS and the LHC is equipped with two beam stoppers (TEDs), one at the beginning of the line and one close to the LHC injection point, which need to absorb the full transferred beam. The beam stoppers are used for setting up the SPS extractions and transfer lines with beam without having to inject into the LHC. Energy deposition and thermo-mechanical simulations have, however, shown that the TEDs will not be robust enough to safely absorb the high intensity beams foreseen for the high-luminosity LHC era. This paper will summarize the simulation results and limitations for upgrading the beam stoppers. An outline of the hardware upgrade strategy for the TEDs together with modifications to the SPS extraction interlock system to enforce intensity limitations for beam on the beam stoppers will be given.

  8. A very sensitive nonintercepting beam average velocity monitoring system for the TRIUMF 300-keV injection line

    International Nuclear Information System (INIS)

    Yin, Y.; Laxdal, R.E.; Zelenski, A.; Ostroumov, P.

    1997-01-01

    A nonintercepting beam velocity monitoring system has been installed in the 300-keV injection line of the TRIUMF cyclotron to reproduce the injection energy for beam from different ion sources and to monitor any beam energy fluctuations. By using a programmable beam signal leveling method the system can work with a beam current dynamic range of 50 dB. Using synchronous detection, the system can detect 0.5 eV peak-to-peak energy modulation of the beam, sensitivity is 1.7x10 -6 . The paper will describe the principle and beam measurement results. copyright 1997 American Institute of Physics

  9. Simulation and beam line experiments for the superconducting ECR ion source VENUS

    International Nuclear Information System (INIS)

    Todd, Damon S.; Leitner, Daniela; Grote, David P.; Lyneis, ClaudeM.

    2007-01-01

    The particle-in-cell code Warp has been enhanced to incorporate both two- and three-dimensional sheath extraction models giving Warp the capability of simulating entire ion beam transport systems including the extraction of beams from plasma sources. In this article we describe a method of producing initial ion distributions for plasma extraction simulations in electron cyclotron resonance (ECR) ion sources based on experimentally measured sputtering on the source biased disc. Using this initialization method, we present preliminary results for extraction and transport simulations of an oxygen beam and compare them with experimental beam imaging on a quartz viewing plate for the superconducting ECR ion source VENUS

  10. Analysis of the proton beam in the DESY transport lines by video readout

    CERN Document Server

    Solodovnik, F; Wittenburg, K

    2000-01-01

    Injection efficiency, beam optic matching and emittance preservation are very important parameters in achieving a high luminosity in large proton accelerators. We improved the analysing system of the phosphor screen readout of the proton transport lines in the accelerator chain of HERA with respect to the parameters above. The screens are read out by simple CCD video cameras. The signals are stored in local frame grabbers. An analogue output of the stored image is multiplexed and read-out by a fast PCI frame grabber card in a PC. The beam orbit and the beam emittance can be measured from each screen. A Visual Basic program is used to displays the trajectory and the envelope of the beam from a single transfer. The same program helps to drive bumps to achieve a proper steering through the line. The beam width can be measured from selected screens to calculate the emittance and other beam parameters including their errors. The read out and analysing system will be described and measurements will be shown.

  11. Modeling space charge in beams for heavy-ion fusion

    International Nuclear Information System (INIS)

    Sharp, W.M.

    1995-01-01

    A new analytic model is presented which accurately estimates the radially averaged axial component of the space-charge field of an axisymmetric heavy-ion beam in a cylindrical beam pipe. The model recovers details of the field near the beam ends that are overlooked by simpler models, and the results compare well to exact solutions of Poisson's equation. Field values are shown for several simple beam profiles and are compared with values obtained from simpler models

  12. Experimental observations and theoretical models for beam-beam phenomena

    International Nuclear Information System (INIS)

    Kheifets, S.

    1981-03-01

    The beam-beam interaction in storage rings exhibits all the characteristics of nonintegrable dynamical systems. Here one finds all kinds of resonances, closed orbits, stable and unstable fixed points, stochastic layers, chaotic behavior, diffusion, etc. The storage ring itself being an expensive device nevertheless while constructed and put into operation presents a good opportunity of experimentally studying the long-time behavior of both conservative (proton machines) and nonconservative (electron machines) dynamical systems - the number of bunch-bunch interactions routinely reaches values of 10 10 -10 11 and could be increased by decreasing the beam current. At the same time the beam-beam interaction puts practical limits for the yield of the storage ring. This phenomenon not only determines the design value of main storage ring parameters (luminosity, space charge parameters, beam current), but also in fact prevents many of the existing storage rings from achieving design parameters. Hence, the problem has great practical importance along with its enormous theoretical interest. A brief overview of the problem is presented

  13. An inexpensive electron beam annealing apparatus with line focus, made from a converted electron welding machine

    International Nuclear Information System (INIS)

    Krimmel, E.F.; Lutsch, AG.K.; Meyer, H.P.; Theron, S.B.K.

    1985-01-01

    Electron beam annealing has, after an active period of research, become an established technology in the production of semiconductor devices, since high quality restoration practically without out-diffusion, can be achieved. Many universities and research institutions cannot afford to purchase a dedicated electron beam annealing apparatus. In the following a conversion of an industrial electron beam welding apparatus into an annealing apparatus with line focus is described, which could easily be copied by interested institutions. A magnetic quadrupole-lens is described which converts the point into a line focus. Standard-TV deflections with a special generator circuit for the X and Y deflection are used. Electron currents of 4 to 5 mA cause silicon to melt (1415 deg C). Annealing results obtained with the apparatus are discussed. (author)

  14. New development of hadron physics at new laser electron beam line (LEP2) of SPring-8

    International Nuclear Information System (INIS)

    Muramatsu, Norihito; Niiyama, Masayuki; Yosoi, Masaru

    2015-01-01

    This paper introduces the outline of LEPS2 beam line and two types of large detectors (electromagnetic calorimeter BGOegg and solenoid spectrometer), LEPS2/BGOegg experiment, and the target physics using LEPS2 solenoid spectrometer. In LEPS2 beam line, experiments are performed with the improvement of beam intensity by nearly one digit due to the simultaneous incidence of multiple lasers of high output, as well as with the installation of a large solid angle high-resolution detector. In LEPS2/BGOegg experiment, direct observation with a large solid angle of mesons such as π 0 , η, η', and ω has become possible, which has given expectation for new physics. As one of the physics at the core of BGOegg experiments, there is the systematic examination of interaction between η' and nucleus/nucleon. In the physics using a solenoid spectrometer, the first target is the measurement of penta-quark particle Θ + . (A.O.)

  15. Beam-line considerations for experiments with highly-charged ions

    International Nuclear Information System (INIS)

    Johnson, B.M.

    1990-01-01

    The APS offers exciting possibilities for a bright future in x-ray research. For example, measurements on the inner-shell photoionization of ions will be feasible using stored ions in ions traps or ion beams from an electron-cyclotron-resonance ion source, or perhaps even a heavy-ion storage ring. Such experiments with ionic targets are the focus for the discussion given here on the optimization of photon flux on a generic beamline at the APS. The performance of beam lines X26C, X26A, and X17 on the x-ray ring of the National Synchrotron Light Source will be discussed as specific examples of beam-line design considerations

  16. Beam-line considerations for experiments with highly-charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, B.M.

    1990-01-01

    The APS offers exciting possibilities for a bright future in x-ray research. For example, measurements on the inner-shell photoionization of ions will be feasible using stored ions in ions traps or ion beams from an electron-cyclotron-resonance ion source, or perhaps even a heavy-ion storage ring. Such experiments with ionic targets are the focus for the discussion given here on the optimization of photon flux on a generic beamline at the APS. The performance of beam lines X26C, X26A, and X17 on the x-ray ring of the National Synchrotron Light Source will be discussed as specific examples of beam-line design considerations.

  17. Shield design for the material science beam line of medical proton cyclotron facility

    International Nuclear Information System (INIS)

    Sarangapani, R.; Meenakshisundaram, V.; Indira, R.; Subbaiah, K.V.

    2007-01-01

    A medical proton cyclotron facility is being commissioned by DAE in Kolkata. The facility will have three dedicated beam lines for i) the production of radioisotopes, ii) Accelerator Driven Systems (ADS) experiments and iii) material science studies. It is proposed to irradiate SS (D9 alloy) samples by Materials Science Division, IGCAR in the material science beam line. The proton energy and current are 30 MeV and 200 μA respectively. It is proposed to irradiate the sample for seven days and retrieve it after a minimum cooling period of 24 h. Proton-induced radionuclides are produced in the target during irradiation. In addition to the induced activity, protons impinging on the sample results in the emission of neutrons. The emitted neutrons interact with the structural materials and produces induced activity. The access to the area is permitted only during shutdown of the beam line and that too after sufficient cooling time. The irradiated target is transferred from irradiation chamber to lead transport cask. When the beam line is in the off state, neutrons are absent and the dose rate at the accessible locations is only from the gamma rays emitted by the target material and induced activity on the structural materials. Calculations have been carried out to estimate the required shielding thickness around the target so that the dose rate at the accessible locations is within acceptable levels. The shield thickness for the lead cask is also estimated. (author)

  18. Beam imaging in the injection line of the INFN-LNS superconducting cyclotron

    Science.gov (United States)

    Nicolosi, Dario; Cosentino, Luigi; Mascali, David; Pappalardo, Alfio; Castro, Maurizio; Celona, Luigi; Marchetta, Carmelo; Marletta, Salvatore; Maugeri, Antonio; Rifuggiato, Danilo; Seminara, Angelo; Gammino, Santo

    2016-02-01

    A cheap and efficient diagnostic system for beam monitoring has been recently developed at INFN-LNS in Catania. It consists of a high sensitivity CCD camera detecting the light produced by an ion beam hitting the surface of a scintillating screen and a frame grabber for image acquisition. A scintillating screen, developed at INFN-LNS and consisting of a 2 μm BaF2 layer evaporated on an aluminium plate, has been tested by using 20Ne and 40Ar beams in the keV energy range. The CAESAR ECR ion source has been used for investigating the influence of the frequency and magnetic field tuning effects, the impact of the microwave injected power, and of the focusing solenoids along the low energy beam transport on the beam shape and current. These tests will allow to better understand the interplay between the plasma and beam dynamics and, moreover, to improve the transport efficiency along the low energy beam line and the matching with the superconducting cyclotron, particularly relevant in view of the expected upgrade of the machine.

  19. Beam imaging in the injection line of the INFN-LNS superconducting cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Nicolosi, Dario, E-mail: dario.nicolosi@lns.infn.it; Cosentino, Luigi; Mascali, David; Pappalardo, Alfio; Castro, Maurizio; Celona, Luigi; Marchetta, Carmelo; Marletta, Salvatore; Maugeri, Antonio; Rifuggiato, Danilo; Seminara, Angelo; Gammino, Santo [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy)

    2016-02-15

    A cheap and efficient diagnostic system for beam monitoring has been recently developed at INFN-LNS in Catania. It consists of a high sensitivity CCD camera detecting the light produced by an ion beam hitting the surface of a scintillating screen and a frame grabber for image acquisition. A scintillating screen, developed at INFN-LNS and consisting of a 2 μm BaF{sub 2} layer evaporated on an aluminium plate, has been tested by using {sup 20}Ne and {sup 40}Ar beams in the keV energy range. The CAESAR ECR ion source has been used for investigating the influence of the frequency and magnetic field tuning effects, the impact of the microwave injected power, and of the focusing solenoids along the low energy beam transport on the beam shape and current. These tests will allow to better understand the interplay between the plasma and beam dynamics and, moreover, to improve the transport efficiency along the low energy beam line and the matching with the superconducting cyclotron, particularly relevant in view of the expected upgrade of the machine.

  20. Fluid-line math model

    Science.gov (United States)

    Kandelman, A.; Nelson, D. J.

    1977-01-01

    Simplified mathematical model simulates large hydraulic systems on either analog or digital computers. Models of pumps, servoactuators, reservoirs, accumulators, and valves are connected generating systems containing six hundred elements.

  1. Power and gas flow models for monoenergetic neutral beam injectors

    International Nuclear Information System (INIS)

    Fasolo, J.A.

    1978-01-01

    Large, ignition tokamak reactors (ITR, EPR, and beyond will require supplemental heating to achieve ignition. In the earlier machines, at least, this heating will probably be provided by monoenergetic neutral beams. These beams, with energies greater than or equal to 150 keV, will most likely be derived from D + or D - ions produced by direct extraction ion sources. A positive ion source will be followed by a bending magnet, a neutralizer, and a second bending magnet. The first magnet will remove molecular ions, and the second one atomic ions. Direct convertors will be used to recover energy from unused molecular and atomic ions. The first bending magnet may be omitted if D - ion sources are used. Models have been developed for power and gas flow in injectors which employ direct extraction D + or D - ion sources. The power flow model accounts explicitly for all beam losses in terms of line densities of gas along paths traversed by ions and neutrals and cross sections for dissociation and charge-changing collisions. The gas flow model uses the results of power flow calculations and known gas flows from sources and neutralizers to determine gas loads and pumping requirements in various parts of the injector

  2. Mathematical model of subscriber extension line

    OpenAIRE

    Petříková, Iva; Diviš, Zdeněk; Tesař, Zdeněk

    2012-01-01

    The paper focuses on measurement properties of metallic subscriber extension lines to build regression mathematical model for a symmetric pair cable. The regression model is compared with an analytical model based on a theoretical description of transfer parameters for this type of line. The output of the paper should demonstrate the impact of electromagnetic interference on the symmetric pair. The paper also describes the method to identify the interference sources and ...

  3. A beam monitoring and validation system for continuous line scanning in proton therapy

    Science.gov (United States)

    Klimpki, G.; Psoroulas, S.; Bula, C.; Rechsteiner, U.; Eichin, M.; Weber, D. C.; Lomax, A.; Meer, D.

    2017-08-01

    Line scanning represents a faster and potentially more flexible form of pencil beam scanning than conventional step-and-shoot irradiations. It seeks to minimize dead times in beam delivery whilst preserving the possibility of modulating the dose at any point in the target volume. Our second generation proton gantry features irradiations in line scanning mode, but it still lacks a dedicated monitoring and validation system that guarantees patient safety throughout the irradiation. We report on its design and implementation in this paper. In line scanning, we steer the proton beam continuously along straight lines while adapting the speed and/or current frequently to modulate the delivered dose. We intend to prevent delivery errors that could be clinically relevant through a two-stage system: safety level 1 monitors the beam current and position every 10 μs. We demonstrate that direct readings from ionization chambers in the gantry nozzle and Hall probes in the scanner magnets provide required information on current and position, respectively. Interlocks will be raised when measured signals exceed their predefined tolerance bands. Even in case of an erroneous delivery, safety level 1 restricts hot and cold spots of the physically delivered fraction dose to  ±36~mGy (±2% of 2~Gy biologically). In safety level 2—an additional, partly redundant validation step—we compare the integral line profile measured with a strip monitor in the nozzle to a forward-calculated prediction. The comparison is performed between two line applications to detect amplifying inaccuracies in speed and current modulation. This level can be regarded as an online quality assurance of the machine. Both safety levels use devices and functionalities already installed along the beamline. Hence, the presented monitoring and validation system preserves full compatibility of discrete and continuous delivery mode on a single gantry, with the possibility of switching between modes during the

  4. Performance of the double multilayer monochromator on the NSLS wiggler beam line X25

    Science.gov (United States)

    Berman, Lonny E.; Yin, Zhijian; Dierker, Steven B.; Dufresne, Eric; Mochrie, Simon G. J.; Tsui, Ophelia K. C.; Burley, Stephen K.; Shu, Fong; Xie, Xiaoling; Capel, Malcolm S.; Sweet, Robert M.

    1997-07-01

    A tunable, double multilayer x-ray monochromator has recently been implemented on the National Synchrotron Light Source (NSLS) X25 wiggler beam line. It is based on a parallel pair of tungsten-boron-carbide multilayer films grown on silicon substrates and purchased from Osmic, Inc. of Troy, Michigan, USA. It acts as an optional alternative to the conventional double silicon crystal monochromator, and uses the same alignment mechanism. Two other NSLS beam lines also have had this kind of monochromator installed recently, following the lead of the NSLS X20C IBM/MIT beam line which has used a double multilayer monochromator for several years. Owing to the 100 times broader bandwidth of a multilayer x-ray monochromator, compared with a silicon monochromator, the multilayer monochromator has the obvious advantage of delivering 100 times the flux of a silicon monochromator, and thereby makes more efficient use of the continuous synchrotron radiation spectrum, yet preserves the narrow collimation of the incident synchrotron beam. In particular, multilayer x-ray bandwidths, on the order of 1%, are well-matched to x-ray undulator linewidths. Performance results for the X25 multilayer monochromator are presented, comparing it with the silicon monochromator. Of note is its short- and long-term performance as an x-ray monochromator delivering the brightness of the wiggler source in the presence of the high-power white beam. Detailed measurements of its spatial beam profile and wavelength dispersion have been made, and it is shown how its resolution could be improved when desired. Finally, its peculiar, anisotropic resolution function in reciprocal space, and its bearing upon x-ray crystallography and scattering experiments, will be discussed, and highlighted by the results of a protein crystallography experiment.

  5. On-line image guided radiation therapy using cone-beam CT (CBCT)

    International Nuclear Information System (INIS)

    Bak, Jin O; Park, Suk Won; Jeong, Kyung Keun; Keum, Ki Chang

    2006-01-01

    Using cone beam CT, we can compare the position of the patients at the simulation and the treatment. In on-line image guided radiation therapy, one can utilize this compared data and correct the patient position before treatments. Using cone beam CT, we investigated the errors induced by setting up the patients when use only the markings on the patients' skin. We obtained the data of three patients that received radiation therapy at the Department of Radiation Oncology in Chung-Ang University during August 2006 and October 2006. Just as normal radiation therapy, patients were aligned on the treatment couch after the simulation and treatment planning. Patients were aligned with lasers according to the marking on the skin that were marked at the simulation time and then cone beam CTs were obtained. Cone beam CTs were fused and compared with simulation CTs and the displacement vectors were calculated. Treatment couches were adjusted according to the displacement vector before treatments. After the treatment, positions were verified with kV X-ray (OBI system). In the case of head and neck patients, the average sizes of the setup error vectors, given by the cone beam CT, were 0.19 cm for the patient A and 0.18 cm for the patient B. The standard deviations were 0.15 cm and 0.21 cm, each. On the other hand, in the case of the pelvis patient, the average and the standard deviation were 0.37 cm and 01 cm. Through the on-line IGRT using cone beam CT, were could correct the setup errors that could occur in the conventional radiotherapy. The importance of the on-line IGRT should be emphasized in the case of 3D conformal therapy and intensity-modulated radiotherapy, which have complex target shapes and steep dose gradients

  6. Laser-line scanning speckle reduction based on a one-dimensional beam homogenizer

    Science.gov (United States)

    Nelsen, B.; Jacobs, P.; Hartmann, P.

    2017-06-01

    Laser-line scanners have become ubiquitous in many forms of automation and measurement systems. Despite this fact, these systems are still susceptible to speckle or interference on rough scattering surfaces. Many scanning systems must be calibrated to the material being analyzed to obtain their full potential. In general, post-processing algorithms are used in most modern line-scanning devices in order to smooth out speckle and enhance the resolution through sub-pixel interpolation. However, these post-processing techniques come at a cost of increased CPU time and a subsequent decrease in bandwidth and resolution. in this paper, a low-cost, high-resolution solution to generating speckle-free sharply focused laser lines is presented. The key to this technique relies on only removing the spatial coherence in one dimension using a 1-D cylindrical lens array as a beam homogenizer. This beam homogenizer is then wrapped around and rotated about a central axis in order to remove the temporal component on the laser's coherence. Since the plane-wave-like behavior is maintained along one dimension, this beam can still be sharply focused to a line. however, the spatial coherence and temporal coherence are reduced to the point that speckle is minimally visible.

  7. Status and Plans for the SPS to LHC Beam Transfer Lines TI 2 and TI 8

    CERN Document Server

    Goddard, B; Risselada, Thys

    2004-01-01

    Beam transfer from the CERN Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC) will be done through the two transfer lines TI 2 and TI 8, presently under construction, with a combined length of about 5.6 km. The final layout, optics design and correction scheme for these lines will be presented. The requirement of simultaneously matching their geometry and optics with that of the LHC will be treated, including the methodology for alignment of the elements along the line and a proposed solution in the final matching section. After the commissioning of the short transfer line TT40 just upstream of TI 8 in 2003, beam tests of the whole of TI 8 are scheduled for autumn 2004, with the aim to validate many of the new features and mechanisms involved in the future control and operation of these lines. The status of the installation will be described, comprising the progress with infrastructure, services and line elements. An outlook will be given for the work remaining until 2007.

  8. A Monte Carlo study for the calculation of the average linear energy transfer (LET) distributions for a clinical proton beam line and a radiobiological carbon ion beam line.

    Science.gov (United States)

    Romano, F; Cirrone, G A P; Cuttone, G; Rosa, F Di; Mazzaglia, S E; Petrovic, I; Fira, A Ristic; Varisano, A

    2014-06-21

    Fluence, depth absorbed dose and linear energy transfer (LET) distributions of proton and carbon ion beams have been investigated using the Monte Carlo code Geant4 (GEometry ANd Tracking). An open source application was developed with the aim to simulate two typical transport beam lines, one used for ocular therapy and cell irradiations with protons and the other for cell irradiations with carbon ions. This tool allows evaluation of the primary and total dose averaged LET and predict their spatial distribution in voxelized or sliced geometries. In order to reproduce the LET distributions in a realistic way, and also the secondary particles' contributions due to nuclear interactions were considered in the computations. Pristine and spread-out Bragg peaks were taken into account both for proton and carbon ion beams, with the maximum energy of 62 MeV/n. Depth dose distributions were compared with experimental data, showing good agreement. Primary and total LET distributions were analysed in order to study the influence of contributions of secondary particles in regions at different depths. A non-negligible influence of high-LET components was found in the entrance channel for proton beams, determining the total dose averaged LET by the factor 3 higher than the primary one. A completely different situation was obtained for carbon ions. In this case, secondary particles mainly contributed in the tail that is after the peak. The results showed how the weight of light and heavy secondary ions can considerably influence the computation of LET depth distributions. This has an important role in the interpretation of results coming from radiobiological experiments and, therefore, in hadron treatment planning procedures.

  9. On-line electron beam measurements for the Los Alamos Free-Electron Laser

    International Nuclear Information System (INIS)

    Lumpkin, A.H.; Feldman, R.B.; Feldman, D.W.; Stein, W.E.

    1987-01-01

    Recent developments in the electron beam diagnostics used on the Los Alamos Free-Electron Laser (FEL) have extended our on-line, quantitative analysis capability to extraction efficiency and micropulse temporal duration. The FEL's 20-MeV electron beam is 100 μs in length and consists of ∼2000 micropulses of 20-ps duration and 46-ns separation. This extreme range of time scales is addressed by employing a combination of synchronized beam deflectors, an electron spectrometer, intensified video cameras, real-time video digitizers, and microcomputers. The tapered wiggler result for extraction efficiency (2%) and results for pulse duration measurements (10 to 15 ps) by two techniques are presented

  10. Proposal for characterization of muon spectrometers for neutrino beam lines with the Baby MIND

    CERN Document Server

    Noah, E

    2015-01-01

    Neutrino detectors based on state-of-the-art plastic scintillators read out with solid state photo-sensors, as well as new magnetization schemes, have been developed in the framework of AIDA. Meaningful size prototypes are under construction. In the framework of the CERN neutrino platform, we propose to test a Totally Active Scintillator Detector (TASD) and a prototype of a Magnetized Iron Neutrino Detector (MIND), called Baby MIND in the H8 beam line in 2016-2018. The design of the detectors and the purpose and plans for the beam tests are presented. An opportunity to use the Baby MIND detector in a real neutrino beam at JPARC for the measurement of the cross-section ratio between Water and scintillator (WAGASCI experiment) is described.

  11. Digitral Down Conversion Technology for Tevatron Beam Line Tuner at FNAL

    Energy Technology Data Exchange (ETDEWEB)

    Schappert, W.; Lorman, E.; Scarpine, V.; Ross, M.C.; Sebek, J.; Straumann, T.; /Fermilab /SLAC

    2008-03-17

    Fermilab is presently in Run II collider operations and is developing instrumentation to improve luminosity. Improving the orbit matching between accelerator components using a Beam Line Tuner (BLT) can improve the luminosity. Digital Down Conversion (DDC) has been proposed as a method for making more accurate beam position measurements. Fermilab has implemented a BLT system using a DDC technique to measure orbit oscillations during injections from the Main Injector to the Tevatron. The output of a fast ADC is downconverted and filtered in software. The system measures the x and y positions, the intensity, and the time of arrival for each proton or antiproton bunch, on a turn-by-turn basis, during the first 1024 turns immediately following injection. We present results showing position, intensity, and time of arrival for both injected and coasting beam. Initial results indicate a position resolution of {approx}20 to 40 microns and a phase resolution of {approx}25 ps.

  12. Digital Down Conversion Technology for Tevatron Beam Line Tuner at FNAL

    International Nuclear Information System (INIS)

    Schappert, W.; Lorman, E.; Scarpine, V.; Ross, M.C.; Sebek, J.; Straumann, T.

    2008-01-01

    Fermilab is presently in Run II collider operations and is developing instrumentation to improve luminosity. Improving the orbit matching between accelerator components using a Beam Line Tuner (BLT) can improve the luminosity. Digital Down Conversion (DDC) has been proposed as a method for making more accurate beam position measurements. Fermilab has implemented a BLT system using a DDC technique to measure orbit oscillations during injections from the Main Injector to the Tevatron. The output of a fast ADC is downconverted and filtered in software. The system measures the x and y positions, the intensity, and the time of arrival for each proton or antiproton bunch, on a turn-by-turn basis, during the first 1024 turns immediately following injection. We present results showing position, intensity, and time of arrival for both injected and coasting beam. Initial results indicate a position resolution of ∼20 to 40 microns and a phase resolution of ∼25 ps

  13. Free Vibration Analysis for Cracked FGM Beams by Means of a Continuous Beam Model

    Directory of Open Access Journals (Sweden)

    E Chuan Yang

    2015-01-01

    Full Text Available Based on Euler-Bernoulli beam theory and a continuous stiffness beam model, the free vibration of rectangular-section beams made of functionally graded materials (FGMs containing open edge cracks is studied. Assuming the material gradients follow exponential distribution along beam thickness direction, the conversion relation between the vibration governing equations of a FGM beam and that of an isotropic homogenous beam is deduced. A continuous function is used to characterize the bending stiffness of an edge cracked FGM beam. Thus, the cracked FGM beam is treated as an intact beam with continuously varying bending stiffness along its longitudinal direction. The characteristic equations of beams with different boundary conditions are obtained by transfer matrix method. To verify the validity of the proposed method, natural frequencies for intact and cracked FGM beams are calculated and compared with those obtained by three-dimensional finite element method (3D FEM and available data in the literature. After that, further discussions are carried out to analyze the influences of crack depth, crack location, material property, and slenderness ratio on the natural frequencies of the cracked FGM beams.

  14. The Advanced Light Source U8 beam line, 20--300 eV

    International Nuclear Information System (INIS)

    Heimann, P.; Warwick, T.; Howells, M.; McKinney, W.; Digennaro, D.; Gee, B.; Yee, D.; Kincaid, B.

    1991-10-01

    The U8 is a beam line under construction at the Advanced Light Source (ALS). The beam line will be described along with calculations of its performance and its current status. An 8 cm period undulator is followed by two spherical collecting mirrors, an entrance slit, spherical gratings having a 15 degree deviation angle, a moveable exit slit, and refocusing and branching mirrors. Internal water cooling is provided to the metal M1 and M2 mirrors as well as to the gratings. Calculations have been made of both the flux output and the resolution over its photon energy range of 20--300 eV. The design goal was to achieve high intensity, 10 12 photons/sec, at a high resolving power of 10,000. The U8 Participating Research Team (PRT) is planning experiments involving the photoelectron spectroscopy of gaseous atoms and molecules, the spectroscopy of ions and actinide spectroscopy

  15. National Synchrotron Light Source users manual: Guide to the VUV and x-ray beam lines

    International Nuclear Information System (INIS)

    Gmuer, N.F.; White-DePace, S.M.

    1987-08-01

    The success of the National Synchrotron Light Source in the years to come will be based, in large part, on the size of the users community and the diversity of the scientific disciplines represented by these users. In order to promote this philosophy, this National Synchrotron Light Source (NSLS) Users Manual: Guide to the VUV and X-Ray Beam Lines, has been published. This manual serves a number of purposes. In an effort to attract new research, it will present to the scientific community-at-large the current and projected architecture and capabilities of the various VUV and x-ray beam lines and storage rings. We anticipate that this publication will be updated periodically in order to keep pace with the constant changes at the NSLS

  16. The Beam Line X NdFe-steel hybrid wiggler for SSRL

    International Nuclear Information System (INIS)

    Hoyer, E.; Halbach, K.; Humphries, D.; Marks, S.; Plate, D.; Shuman, D.; Karpenko, V.P.; Kulkarni, S.; Tirsell, K.G.

    1987-01-01

    A wiggler magnet with 15 periods, each 12.85 cm long, which achieves 1.40 T at a 2.1 cm gap (2.26T at 0.8 cm) has been designed and is now in fabrication at LBL. This wiggler will be the radiation source of the high intensity synchrotron radiation beam line for the Beam Line X PRT facility at SSRL. The magnet utilizes Neodymium-Iron (NdFe) material and Vanadium Permendur (steel) in the hybrid configuration to achieve simultaneously a high magnetic field and short period. Magnetic field adjustment is with a driven chain and ball screw drive system. The magnetic structure is external to an s.s. vacuum chamber which has thin walls, 0.76 mm thickness, at each pole tip for higher field operation. Magnetic design, construction details and magnetic measurements are presented

  17. Selection and evaluation of an ultra high vacuum gate valve for Isabelle beam line vacuum system

    International Nuclear Information System (INIS)

    Foerster, C.L.; McCafferty, D.

    1980-01-01

    A minimum of eighty-four (84) Ultra High Vacuum Gate Valves will be utilized in ISABELLE to protect proton beam lines from catastrophic vacuum failure and to provide sector isolation for maintenance requirements. The valve to be selected must function at less than 1 x 10 -11 Torr pressure and be bakeable to 300 0 C in its open or closed position. In the open position, the valve must have an RF shield to make the beam line walls appear continuous. Several proposed designs were built and evaluated. The evaluation consisted mainly of leak testing, life tests, thermal cycling, mass spectrometer analysis, and 10 -12 Torr operation. Problems with initial design and fabrication were resolved. Special requirements for design and construction were developed. This paper describes the tests on two final prototypes which appear to be the best candidates for ISABELLE operation

  18. Fast Pencil Beam Dose Calculation for Proton Therapy Using a Double-Gaussian Beam Model.

    Science.gov (United States)

    da Silva, Joakim; Ansorge, Richard; Jena, Rajesh

    2015-01-01

    The highly conformal dose distributions produced by scanned proton pencil beams (PBs) are more sensitive to motion and anatomical changes than those produced by conventional radiotherapy. The ability to calculate the dose in real-time as it is being delivered would enable, for example, online dose monitoring, and is therefore highly desirable. We have previously described an implementation of a PB algorithm running on graphics processing units (GPUs) intended specifically for online dose calculation. Here, we present an extension to the dose calculation engine employing a double-Gaussian beam model to better account for the low-dose halo. To the best of our knowledge, it is the first such PB algorithm for proton therapy running on a GPU. We employ two different parameterizations for the halo dose, one describing the distribution of secondary particles from nuclear interactions found in the literature and one relying on directly fitting the model to Monte Carlo simulations of PBs in water. Despite the large width of the halo contribution, we show how in either case the second Gaussian can be included while prolonging the calculation of the investigated plans by no more than 16%, or the calculation of the most time-consuming energy layers by about 25%. Furthermore, the calculation time is relatively unaffected by the parameterization used, which suggests that these results should hold also for different systems. Finally, since the implementation is based on an algorithm employed by a commercial treatment planning system, it is expected that with adequate tuning, it should be able to reproduce the halo dose from a general beam line with sufficient accuracy.

  19. Development of a polarized neutron beam line at Algerian research reactors using McStas software

    Energy Technology Data Exchange (ETDEWEB)

    Makhloufi, M., E-mail: makhloufi_8m@yahoo.fr [Centre de Recherche Nucléaire de Birine (Algeria); Salah, H. [Centre de Recherche Nucléaire d' Alger (Algeria)

    2017-02-01

    Unpolarized instrumentation has long been studied and designed using McStas simulation tool. But, only recently new models were developed for McStas to simulate polarized neutron scattering instruments. In the present contribution, we used McStas software to design a polarized neutron beam line, taking advantage of the available spectrometers reflectometer and diffractometer in Algeria. Both thermal and cold neutron was considered. The polarization was made by two types of supermirrors polarizers FeSi and CoCu provided by the HZB institute. For sake of performance and comparison, the polarizers were characterized and their characteristics reproduced. The simulated instruments are reported. Flipper and electromagnets for guide field are developed. Further developments including analyzers and upgrading of the existing spectrometers are underway. - Highlights: • Permit to evaluate the feasibility of a polarized neutron scattering instrument prior to its implementation. • Help to understand the origin of instrumental imperfections and offer an optimized set up configuration. • Provide the possibility to use the FeSi and CoCu supermirrors, designed to polarize spin up cold neutron, to polarize thermal neutron.

  20. Experimental studies on coherent synchrotron radiation at an emittance exchange beam line

    Directory of Open Access Journals (Sweden)

    J. C. T. Thangaraj

    2012-11-01

    Full Text Available One of the goals of the Fermilab A0 photoinjector is to investigate experimentally the transverse to longitudinal emittance exchange (EEX principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy-chirped beam.

  1. The development of an expert system to tune a beam line

    International Nuclear Information System (INIS)

    Schultz, D.E.; Brown, P.A.; British Columbia Univ., Vancouver, BC

    1989-01-01

    The experience of developing an Expert System to aid in the tuning of the Ion Source Injection beam line at TRIUMF is described. The challenging and complex task of introducing Expert System technology into an established accelerator operation is outlined. Success in this environment depends strongly on the choice of project, the choice of experts, the choice of tools, and the methods used to represent the expertise. All these choices are discussed

  2. EUV spectral lines of highly-charged Hf, Ta and Au ions observed with an electron beam ion trap

    International Nuclear Information System (INIS)

    Draganic, Ilija N; Ralchenko, Yuri; Reader, Joseph; Gillaspy, J D; Tan, Joseph N; Pomeroy, Joshua M; Brewer, Samuel M; Osin, Dmitry

    2011-01-01

    Extreme ultraviolet spectra of highly-charged hafnium, tantalum and gold were produced with an electron beam ion trap (EBIT) at the National Institute of Standards and Technology (NIST) and recorded with a flat-field grazing-incidence spectrometer in the wavelength range 4-20 nm. The beam energy was varied between 1.84 and 5.15 keV to selectively enhance spectra from specific ionization stages. Identifications of strong n = 4-n = 4 transitions from Rb-like hafnium (35+) to Co-like gold (52+) were determined with the aid of collisional-radiative modelling of the EBIT plasma. Good quantitative agreement between simulated and measured spectra was achieved. Over 150 spectral lines were identified, 115 of which are new.

  3. EUV spectral lines of highly-charged Hf, Ta and Au ions observed with an electron beam ion trap

    Energy Technology Data Exchange (ETDEWEB)

    Draganic, Ilija N; Ralchenko, Yuri; Reader, Joseph; Gillaspy, J D; Tan, Joseph N; Pomeroy, Joshua M; Brewer, Samuel M; Osin, Dmitry, E-mail: yuri.ralchenko@nist.gov [National Institute of Standards and Technology, Gaithersburg, MD 20899-8422 (United States)

    2011-01-28

    Extreme ultraviolet spectra of highly-charged hafnium, tantalum and gold were produced with an electron beam ion trap (EBIT) at the National Institute of Standards and Technology (NIST) and recorded with a flat-field grazing-incidence spectrometer in the wavelength range 4-20 nm. The beam energy was varied between 1.84 and 5.15 keV to selectively enhance spectra from specific ionization stages. Identifications of strong n = 4-n = 4 transitions from Rb-like hafnium (35+) to Co-like gold (52+) were determined with the aid of collisional-radiative modelling of the EBIT plasma. Good quantitative agreement between simulated and measured spectra was achieved. Over 150 spectral lines were identified, 115 of which are new.

  4. C. Petrone et al.: "Magnetic measurement of the model magnet QD0 designed for the CLIC final focus beam transport line." CERN TE-MSC Internal Note, EDMS Nr: 1184196

    CERN Document Server

    Arpaia, Pasquale; Petrone, Carlo; Russenschuck, Stephan; Walckiers, Louis

    2012-01-01

    This note presents the results of the magnetic measurements performed on QD0, model magnet for the final focus transport line for CLIC (Fig. 1). This high-gradient, hybrid quadrupole has a yoke length of 0.1 m and an aperture of 8.3 mm. ND2Fe14B Permanent magnet blocks provide a gradient of 150 T/m, which can be further increased to 530 T/m when the four coils are excited to 18.3 A. The request was to measure the strength of the field and the multipole coefficients at different currents. The measurement of the field strength, by means of the single stretched wire system, was done in December 2011 in the I8 laboratory. The measurement of the multipole was done by means of the oscillating wire system [1][2].

  5. Improved design of proton source and low energy beam transport line for European Spallation Source

    Science.gov (United States)

    Neri, L.; Celona, L.; Gammino, S.; Mascali, D.; Castro, G.; Torrisi, G.; Cheymol, B.; Ponton, A.; Galatà, A.; Patti, G.; Gozzo, A.; Lega, L.; Ciavola, G.

    2014-02-01

    The design update of the European Spallation Source (ESS) accelerator is almost complete and the construction of the prototype of the microwave discharge ion source able to provide a proton beam current larger than 70 mA to the 3.6 MeV Radio Frequency Quadrupole (RFQ) started. The source named PS-ESS (Proton Source for ESS) was designed with a flexible magnetic system and an extraction system able to merge conservative solutions with significant advances. The ESS injector has taken advantage of recent theoretical updates and new plasma diagnostics tools developed at INFN-LNS (Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare). The design strategy considers the PS-ESS and the low energy beam transport line as a whole, where the proton beam behaves like an almost neutralized non-thermalized plasma. Innovative solutions have been used as hereinafter described. Thermo-mechanical optimization has been performed to withstand the chopped beam and the misaligned focused beam over the RFQ input collimator; the results are reported here.

  6. Improved design of proton source and low energy beam transport line for European Spallation Source

    Energy Technology Data Exchange (ETDEWEB)

    Neri, L., E-mail: neri@lns.infn.it; Celona, L.; Gammino, S.; Mascali, D.; Castro, G.; Ciavola, G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, 95123 Catania (Italy); Torrisi, G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Ingegneria dell’Informazione, delle Infrastrutture e dell’Energia Sostenibile, Università Mediterranea di Reggio Calabria, Via Graziella, 89122 Reggio Calabria (Italy); Cheymol, B.; Ponton, A. [European Spallation Source ESS AB, Lund (Sweden); Galatà, A. [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell' università 2, 35020 Legnaro (Italy); Patti, G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, 95123 Catania (Italy); Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Viale dell' università 2, 35020 Legnaro (Italy); Gozzo, A.; Lega, L. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Ingegneria Informatica e delle Telecomunicazioni, Università degli Studi di Catania, Viale Andrea Doria 6, 95123 Catania (Italy)

    2014-02-15

    The design update of the European Spallation Source (ESS) accelerator is almost complete and the construction of the prototype of the microwave discharge ion source able to provide a proton beam current larger than 70 mA to the 3.6 MeV Radio Frequency Quadrupole (RFQ) started. The source named PS-ESS (Proton Source for ESS) was designed with a flexible magnetic system and an extraction system able to merge conservative solutions with significant advances. The ESS injector has taken advantage of recent theoretical updates and new plasma diagnostics tools developed at INFN-LNS (Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare). The design strategy considers the PS-ESS and the low energy beam transport line as a whole, where the proton beam behaves like an almost neutralized non-thermalized plasma. Innovative solutions have been used as hereinafter described. Thermo-mechanical optimization has been performed to withstand the chopped beam and the misaligned focused beam over the RFQ input collimator; the results are reported here.

  7. A neutral beam-line installation for testing injector systems in the long pulse, megawatt regime

    International Nuclear Information System (INIS)

    Brookes, C.E.; Coupland, J.R.; Green, T.S.; Hammond, D.P.; Hicks, J.B.; Hoskins, A.J.; Pedley, T.R.; West, W.A.

    1981-01-01

    The existing Megawatt Beam Line assembly is being upgraded primarily in order to test prototype JET injector modules to the full rating of 80 Kv, 60 A for pulse durations up to 5 seconds. Two extra vacuum tanks are being installed, together with additional cryopumps to bring the total pumping speed to 4 x 10 5 l/s, and an inertial beam stop calorimeter capable of absorbing the full beam power is being manufactured. The auxiliary electrical supply system is being re-designed to match the proposed 'bucket' type plasma source; the new 144 Kw arc supply has a quasi constant power characteristic in order to reduce fluctuations in beam intensity, and the filament supply is designed to stabilise the source cathodes in the required emission limited mode. The high voltage supply has 120 Kv open circuit voltage for the full beam current and a commercial series tube system which will provide voltage stabilisation, tracking, and fast protection has been ordered from the Systems, Science and Software Company. The assembly and testing of all major components is planned to be completed by early 1981 in order to meet the expected delivery time of the first JET prototype injector. (author)

  8. The model of beam-plasma discharge in the rocket environment during an electron beam injection in the ionosphere

    International Nuclear Information System (INIS)

    Mishin, E.V.; Ruzhin, Yu.Ya.

    1980-01-01

    The model of beam-plasma discharge in the rocket environment during electron beam injection in the ionosphere is constructed. The discharge plasma density dependence on the neutral gas concentration and the beam parameters is found

  9. A high intensity beam line of γ-rays up to 22MeV energy based on Compton backscattering

    International Nuclear Information System (INIS)

    Guo, W.; Xu, W.; Chen, J.G.; Ma, Y.G.; Cai, X.Z.; Wang, H.W.; Xu, Y.; Wang, C.B.; Lu, G.C.; Tian, W.D.; Yuan, R.Y.; Xu, J.Q.; Wei, Z.Y.; Yan, Z.; Shen, W.Q.

    2007-01-01

    Shanghai Laser Electron Gamma Source, a high intensity beam line of γ-ray, has been proposed recently. The beam line is expected to generate γ-rays up to the maximum energy of 22MeV by Compton backscattering between a CO 2 laser and electrons in the 3.5 GeV storage ring of the Shanghai Synchrotron Radiation Facility. The flux of non-collimated γ-rays is estimated to be 10 9 -10 10 s -1 when a CO 2 laser of several hundred Watt power is employed. We will discuss physics issues in the design and optimization of the beam line

  10. Model to Design Drip Hose Lateral Line

    Science.gov (United States)

    Ludwig, Rafael; Cury Saad, João Carlos

    2014-05-01

    Introduction The design criterion for non-pressure compensating drip hose is normally to have 10% of flow variation (Δq) in the lateral line, corresponding to 20% of head pressure variation (ΔH). Longer lateral lines in drip irrigation systems using conventional drippers provide cost reduction, but it is necessary to obtain to the uniformity of irrigation [1]. The use of Δq higher levels can provide longer lateral lines. [4] proposes the use of a 30% Δq and he found that this value resulted in distribution uniformity over 80%. [1] considered it is possible to extend the lateral line length using two emitters spacing in different section. He assumed that the spacing changing point would be at 40% of the total length, because this is approximately the location of the average flow according with [2]. [3] found that, for practical purposes, the average pressure is located at 40% of the length of the lateral line and that until this point it has already consumed 75% of total pressure head loss (hf ). In this case, the challenge for designers is getting longer lateral lines with high values of uniformity. Objective The objective of this study was to develop a model to design longer lateral lines using non-pressure compensating drip hose. Using the developed model, the hypotheses to be evaluated were: a) the use of two different spacing between emitters in the same lateral line allows longer length; b) it is possible to get longer lateral lines using high values of pressure variation in the lateral lines since the distribution uniformity stays below allowable limits. Methodology A computer program was developed in Delphi® based on the model developed and it is able to design lateral lines in level using non-pressure compensating drip hose. The input data are: desired distribution uniformity (DU); initial and final pressure in the lateral line; coefficients of relationship between emitter discharge and pressure head; hose internal diameter; pipe cross-sectional area

  11. Laser alignment measurement model with double beam

    Science.gov (United States)

    Mo, Changtao; Zhang, Lili; Hou, Xianglin; Wang, Ming; Lv, Jia; Du, Xin; He, Ping

    2012-10-01

    Double LD-Double PSD schedule.employ a symmetric structure and there are a laser and a PSD receiver on each axis. The Double LD-Double PSD is used, and the rectangular coordinate system is set up by use of the relationship of arbitrary two points coordinates, and then the parameter formula is deduced by the knowledge of solid geometry. Using the data acquisition system and the data processing model of laser alignment meter with double laser beam and two detector , basing on the installation parameter of the computer, we can have the state parameter between the two shafts by more complicated calculation and correction. The correcting data of the four under chassis of the adjusted apparatus moving on the level and the vertical plane can be calculated using the computer. This will instruct us to move the apparatus to align the shafts.

  12. Implementation of a Direct Link between the LHC Beam Interlock System and the LHC Beam Dumping System Re-Triggering Lines

    CERN Document Server

    Gabourin, S; Denz, R; Magnin, N; Uythoven, J; Wollmann, D; Zerlauth, M; Vatansever, V; Bartholdt, M; Bertsche, B; Zeiler, P

    2014-01-01

    To avoid damage of accelerator equipment due to impacting beam, the controlled removal of the LHC beams from the collider rings towards the dump blocks must be guaranteed at all times. When a beam dump is demanded, the Beam Interlock System communicates this request to the Trigger Synchronisation and Distribution System of the LHC Beam Dumping System. Both systems were built according to high reliability standards. To further reduce the risk of incapability to dump the beams in case of correlated failures in the Trigger Synchronisation and Distribution System, a new direct link from the Beam Interlock System to the re-triggering lines of the LHC Beam Dumping System will be implemented for the start-up with beam in 2015. The link represents a diverse redundancy to the current implementation, which should neither significantly increase the risk for so-called asynchronous beam dumps nor compromise machine availability. This paper describes the implementation choices of this link. Furthermore the results of a rel...

  13. Identification of dental root canals and their medial line from micro-CT and cone-beam CT records

    Directory of Open Access Journals (Sweden)

    Benyó Balázs

    2012-10-01

    Full Text Available Abstract Background Shape of the dental root canal is highly patient specific. Automated identification methods of the medial line of dental root canals and the reproduction of their 3D shape can be beneficial for planning endodontic interventions as severely curved root canals or multi-rooted teeth may pose treatment challenges. Accurate shape information of the root canals may also be used by manufacturers of endodontic instruments in order to make more efficient clinical tools. Method Novel image processing procedures dedicated to the automated detection of the medial axis of the root canal from dental micro-CT and cone-beam CT records are developed. For micro-CT, the 3D model of the root canal is built up from several hundred parallel cross sections, using image enhancement, histogram based fuzzy c-means clustering, center point detection in the segmented slice, three dimensional inner surface reconstruction, and potential field driven curve skeleton extraction in three dimensions. Cone-beam CT records are processed with image enhancement filters and fuzzy chain based regional segmentation, followed by the reconstruction of the root canal surface and detecting its skeleton via a mesh contraction algorithm. Results The proposed medial line identification and root canal detection algorithms are validated on clinical data sets. 25 micro-CT and 36 cone-beam-CT records are used in the validation procedure. The overall success rate of the automatic dental root canal identification was about 92% in both procedures. The algorithms proved to be accurate enough for endodontic therapy planning. Conclusions Accurate medial line identification and shape detection algorithms of dental root canal have been developed. Different procedures are defined for micro-CT and cone-beam CT records. The automated execution of the subsequent processing steps allows easy application of the algorithms in the dental care. The output data of the image processing procedures

  14. Proposed particle-beam characterizations for the APS undulator test line

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A.H.; Borland, M.; Milton, S.

    1993-09-01

    A research and development effort is underway at the Advanced Photon Source (APS) to use an rf gun as a low-emittance electron source for injection into the 100- to 650-MeV linac subsystem and subsequently to an undulator test area. This configuration would combine the acceleration capability of the 200-MeV S-band electron linac and the in-line 450-MeV positron linac that normally provide positrons to the positron accumulator ring (PAR). A transport line that bypasses the PAR will bring the electrons to the undulator test area. Characterization techniques will be discussed for the electron beam with a normalized, rms emittance of <10 {pi} mm mrad (1{sigma}) at micropulse charges of up to 350 pC and micropulse durations of {approximately}5 ps (FWHM). Tests proposed include measurement of particle beam transport effects (at one-tenth the storage ring beam rigidity) caused by small undulator field errors as well as operations intended to produce coherent, short wavelength radiation (<200 nm).

  15. Expanded beam spectro-ellipsometry for big area on-line monitoring

    Science.gov (United States)

    Fried, M.; Major, C.; Juhasz, G.; Petrik, P.; Horvath, Z.

    2015-05-01

    Non-destructive analysing tools are needed at all stages of thin film process-development, especially photovoltaic (PV) development, and on production lines. In the case of thin films, layer thicknesses, micro-structure, composition, layer optical properties, and their uniformity are important parameters. An important focus is to express the dielectric functions of each component material in terms of a handful of wavelength independent parameters whose variation can cover all process variants of that material. With the resulting database, spectroscopic ellipsometry coupled with multilayer analysis can be developed for on-line point-by-point mapping and on-line line-by-line imaging. Off-line point-by-point mapping can be effective for characterization of non-uniformities in full scale PV panels or big area (even 450 mm diameter) Si-wafers in developing labs but it is slow in the on-line mode when only 15 points can be obtained (within 1 min) as a 120 cm long panel moves by the mapping station. Last years [M. Fried et al, Thin Solid Films 519, 2730 (2011)], a new instrumentation was developed that provides a line image of spectroscopic ellipsometry (wl=350- 1000 nm) data. Earlier a single 30 point line image could be collected in 10 s over a 15 cm width of PV material. Recent years we have built a 30, a 45 and a 60 cm width expanded beam ellipsometer which speed is increased by 10x. Now, 1800 points can be mapped in a 1 min traverse of a 60*120 cm PV panel or flexible roll-to-roll substrate.

  16. Damping beam displacements through phase mixing: an illustrative model

    International Nuclear Information System (INIS)

    Barletta, W.A.; Briggs, R.J.

    1983-01-01

    We develop a simple model of a beam transported in a hard wall channel (an idealized very-high-order magnetic-multipole channel). The extremely anharmonic nature of the potential leads to damping of coherent transverse displacements of the beam via phase mixing. For the case of small uniform displacements of the beam we can write down by inspection the analytical form of the motion of the beam centroid. The same technique allows us to evaluate the effects of focussing and scattering elements in the transport channel upon the damping of the transverse motion of the beam

  17. Analytical Model for Fictitious Crack Propagation in Concrete Beams

    DEFF Research Database (Denmark)

    Ulfkjær, J. P.; Krenk, S.; Brincker, Rune

    An analytical model for load-displacement curves of unreinforced notched and un-notched concrete beams is presented. The load displacement-curve is obtained by combining two simple models. The fracture is modelled by a fictitious crack in an elastic layer around the mid-section of the beam. Outside...... the elastic layer the deformations are modelled by the Timoshenko beam theory. The state of stress in the elastic layer is assumed to depend bi-lineary on local elongation corresponding to a linear softening relation for the fictitious crack. For different beam size results from the analytical model...... is compared with results from a more accurate model based on numerical methods. The analytical model is shown to be in good agreement with the numerical results if the thickness of the elastic layer is taken as half the beam depth. Several general results are obtained. It is shown that the point on the load...

  18. Analytical Model for Fictitious Crack Propagation in Concrete Beams

    DEFF Research Database (Denmark)

    Ulfkjær, J. P.; Krenk, Steen; Brincker, Rune

    1995-01-01

    An analytical model for load-displacement curves of concrete beams is presented. The load-displacement curve is obtained by combining two simple models. The fracture is modeled by a fictitious crack in an elastic layer around the midsection of the beam. Outside the elastic layer the deformations...... are modeled by beam theory. The state of stress in the elastic layer is assumed to depend bilinearly on local elongation corresponding to a linear softening relation for the fictitious crack. Results from the analytical model are compared with results from a more detailed model based on numerical methods...... for different beam sizes. The analytical model is shown to be in agreement with the numerical results if the thickness of the elastic layer is taken as half the beam depth. It is shown that the point on the load-displacement curve where the fictitious crack starts to develop and the point where the real crack...

  19. A new on-line luminometer and beam conditions monitor using single crystal diamond sensors

    CERN Document Server

    CMS Collaboration

    2015-01-01

    Instrumentation near the beam-pipe requires extremely radiation hard sensors. Inside CMS two rings instrumented with 12 single crystal diamond sensors each are installed on both sides of the interaction point. The sensors are subdivided in two pads, and each pad is read out by a dedicated fast radiation hard ASIC in 130 nm CMOS technology. Due to the excellent time resolution collision products will be separated from machine induced background. In the backend a dead-time less histogramming unit is used, and a fast microTCA system with GHz sampling rate is under development. The detector will measure both the on-line luminosity and the background bunch-by-bunch. The performance of a prototype detector in a test-beam will be reported, and results from the operation during data taking will be presented.

  20. A new on-line luminometer and beam conditions monitor using single crystal diamond sensors

    CERN Document Server

    Karacheban, Olena

    2015-01-01

    Instrumentation near the beam-pipe requires extremely radiation hardsensors. Inside CMS two rings instrumented with 12 single crystal diamondsensors each are installed on both sides of the interaction point. Thesensors are subdivided in two pads, and each pad is read out by adedicated fast radiation hard ASIC in 130 nm CMOS technology.Due to the excellent time resolution collision products will be separatedfrom machine induced background. In the backend a dead-time lesshistogramming unit is udsed, and a fast microTCA system with GHz samplingrate is under development.The detector will measure both the on-line luminosity and the backgroundbunch-by-bunch.The performance of a prototype detector in a test-beam will be reported,and results from the operation during data taking will be presented.

  1. Target and orbit feedback simulations of a muSR beam line at BNL

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-07-28

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. For a dc beam an ideal µSR flux for surface µ+ should be about 40 kHz/mm2. In this report we show how this flux could be achieved in a beam line using the AGS complex at BNL for a source of protons. We also determined that an orbit feedback system with a pair of thin silicon position monitors and kickers would miss the desired flux by at least an order of magnitude, even with perfect time resolution and no multiple scattering.

  2. Exciting Science being done on the CG-2 Small Angle Neutron Scattering beam line at HFIR

    Science.gov (United States)

    Debeer-Schmitt, Lisa; Bailey, Kathy; Melnichenko, Yuri; Wignall, George; Littrell, Ken

    2010-03-01

    The small-angle neutron scattering (SANS) beam line, CG-2, has been in operation since 2007. CG-2 has been optimized so that structures from 0.5 to 200 nm can be thoroughly investigated. HFIR's cold source places the flux at CG-2 among the best in the world. Along with high flux, many varied sample environments can easily be integrated into the beam line which gives the user a versatile temperature range from 1.5 K to 1000K. In addition there are two cryomagents (horizontal 4.5 T and vertical 7 T), pressure cells and load frames available to users allowing for the availability of multiple configurations of experimental setups. Due to all the above equipment and the flux at CG-2, there have been many diverse and intriguing scientific developments. One such outcome is the study of flux- line lattices found in Type-II superconductors including the highly touted iron pnictides. Besides superconductors, other science studied on CG2 ranges from molecular self-assembly and interactions in complex fluids to phase separation, grain growth and orientation in metallurgical alloys.

  3. Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

    International Nuclear Information System (INIS)

    Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

    1987-08-01

    New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs

  4. Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

    Energy Technology Data Exchange (ETDEWEB)

    Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

    1987-08-01

    New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs.

  5. Statistical Model Checking for Product Lines

    DEFF Research Database (Denmark)

    ter Beek, Maurice H.; Legay, Axel; Lluch Lafuente, Alberto

    2016-01-01

    We report on the suitability of statistical model checking for the analysis of quantitative properties of product line models by an extended treatment of earlier work by the authors. The type of analysis that can be performed includes the likelihood of specific product behaviour, the expected...... average cost of products (in terms of the attributes of the products’ features) and the probability of features to be (un)installed at runtime. The product lines must be modelled in QFLan, which extends the probabilistic feature-oriented language PFLan with novel quantitative constraints among features...... behaviour converge in a discrete-time Markov chain semantics, enabling the analysis of quantitative properties. Technically, a Maude implementation of QFLan, integrated with Microsoft’s SMT constraint solver Z3, is combined with the distributed statistical model checker MultiVeStA, developed by one...

  6. Coulomb field strength measurement by electro-optic spectral decoding system at the CALIFES beam line

    CERN Document Server

    Pan, R; Lefevre, T; Gillepsie, WA; CERN. Geneva. ATS Department

    2016-01-01

    Electro-optic (EO) techniques are increasingly used for longitudinal bunch profile measurements. A bunch profile monitor, based on electro-optic spectral decoding(EOSD), has been developed and demonstrated on the CALIFES beam line at CERN. The EO response is analysed using a frequency domain description, and two methods for extraction of absolute Coulomb field strengths from the electron bunch are demonstrated. Measurements at field strengths up to 1.3 MV/m agree with the expectation based on independent charge measurements.

  7. 100 years of Elementary Particles [Beam Line, vol. 27, issue 1, Spring 1997

    Science.gov (United States)

    Pais, Abraham; Weinberg, Steven; Quigg, Chris; Riordan, Michael; Panofsky, Wolfgang K. H.; Trimble, Virginia

    1997-04-01

    This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe.

  8. 100 years of elementary particles [Beam Line, vol. 27, number 1, Spring 1997

    International Nuclear Information System (INIS)

    Pais, Abraham; Weinberg, Steven; Quigg, Chris; Riordan, Michael; Panofsky, Wolfgang K.H.; Trimble, Virginia

    1997-01-01

    This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe

  9. FLOC: Field Line and Orbit Code for the study of ripple beam injection into tokamaks

    International Nuclear Information System (INIS)

    Fowler, R.H.; Lee, D.K.; Gaffney, P.W.; Rome, J.A.

    1978-06-01

    The computer code described is used to study ripple beam injection into a tokamak plasma. The collisionless guiding center equations of motion are integrated to find the orbits of single particles in realistic magnetic fields for ripple injection. In order to determine if the ripple is detrimental to the plasma, the magnetic flux surfaces are constructed by integration of the field line equations. The numerical techniques are described, and use of the code is outlined. A program listing is provided, and the results of sample cases are presented

  10. 100 years of elementary particles [Beam Line, vol. 27, issue 1, Spring 1997

    Energy Technology Data Exchange (ETDEWEB)

    Pais, Abraham; Weinberg, Steven; Quigg, Chris; Riordan, Michael; Panofsky, Wolfgang K.H.; Trimble, Virginia

    1997-04-01

    This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe.

  11. Modeling Field Line Resonances in the Inner Plasmasphere with the Field Line Interhemispheric Plasma Model

    Science.gov (United States)

    McCarthy, N. M.; Jorgensen, A. M.; Stone, W. D.; Zesta, E.

    2010-12-01

    Equatorial plasma mass density in the Inner Magnetosphere of the Earth has been traditionally derived from measurements of Field Line Resonances from pairs of ground magnetometers closely spaced in latitude. The full plasma mass density along the flux tube can be determined using such measurements in an inversion of the Field Line Resonance Equation. Cummings et al [1969] developed the Field Line Resonance equation and numerically solved for the Field Line Resonances by assuming a power law distribution that varied with the geocentric distance from the equatorial crossing point of the field lines and a dipole model for the Earth's magnetic field. So far all numerical solutions of the Field Line Resonance Equation use some form of a power law distribution of the mass density along the field line, that depends on the magnetic field model, typically assumed to be a dipole, with only one recent work exploring deviations from a dipole magnetic field. Another fundamental assumption in the solution of the Field Line Resonance Equation is that of perfectly conducting, flat ionospheres as the two boundaries of the field line. While this assumption is considered valid for L values greater than 2, recent works have found it to be invalid for L values of 3 or less. In the present paper we solve the Field Line Resonance Equation for L values less than 3.5 using a three dimensional ionosphere, and without assuming a power law for the mass density distribution along the field line. Instead we use plasma mass density data from the Field Line Interhemispheric Plasma (FLIP) model to numerically solve the Field Line Resonance Equation for the eigenfrequencies. We also examine how the resonance frequencies vary as a function of the driving parameters. Finally we examine two events in which we compare the derived frequencies with measurements from the SAMBA magnetometer array.

  12. Design and construction of UVSOR-BL4A2 beam line for nano-structure processing

    CERN Document Server

    Takezoe, N; Tanaka, T; Kurosawa, K; Nonogaki, Y; Noda, H; Mekaru, H; Urisu, T

    2001-01-01

    We have designed and constructed a new beam line BL4A2 at UVSOR mainly for nano-structure fabrication based on synchrotron radiation stimulated surface photochemical reactions. In order to obtain high-photon flux, we use white ray beam focused with only one mirror. The beam line is connected with ultra-high vacuum scanning tunneling microscope for in-situ atomic scale observations, low energy electron diffraction and Auger electron spectroscope for surface crystal structure characterization, and photo-stimulated surface reaction chamber. In order to monitor the optical properties with atomic scale, a near field optical microscope is planned to be installed.

  13. The charge breeder beam line for the selective production of exotic species project at INFN-Legnaro National Laboratories

    Science.gov (United States)

    Galatà, A.; Comunian, M.; Maggiore, M.; Manzolaro, M.; Angot, J.; Lamy, T.

    2014-02-01

    SPES (Selective Production of Exotic Species) is an INFN (Istituto Nazionale di Fisica Nucleare) project with the aim at producing and post-accelerating exotic beams to perform forefront research in nuclear physics. To allow post-acceleration of the radioactive ions, an ECR-based Charge Breeder (CB) developed on the basis of the Phoenix booster was chosen. The design of the complete beam line for the SPES-CB will be described: a system for stable 1+ beams production was included; special attention was paid to the medium resolution mass spectrometer after the CB to limit possible superposition of the exotic beams with the impurities present in the ECR plasma.

  14. Determination of the sequence of intersecting lines using Focused Ion Beam/Scanning Electron Microscope.

    Science.gov (United States)

    Kim, Jiye; Kim, MinJung; An, JinWook; Kim, Yunje

    2016-05-01

    The aim of this study was to verify that the combination of focused ion beam (FIB) and scanning electron microscope/energy-dispersive X-ray (SEM/EDX) could be applied to determine the sequence of line crossings. The samples were transferred into FIB/SEM for FIB milling and an imaging operation. EDX was able to explore the chemical components and the corresponding elemental distribution in the intersection. The technique was successful in determining the sequence of heterogeneous line intersections produced using gel pens and red sealing ink with highest success rate (100% correctness). These observations show that the FIB/SEM was the appropriate instrument for an overall examination of document. © 2016 American Academy of Forensic Sciences.

  15. Impact of the New CLIC Beam Parameters on the Design of the Post-Collision Line and its Exit Window

    CERN Document Server

    Ferrari, A

    2008-01-01

    Following the recent modification of the CLIC beam parameters, we present an updated design of the post-collision line. As a result of the increase of the beamstrahlung photon cone size, the separation of the outgoing beams by the vertical magnetic chicane is more difficult, but still possible. The main changes in the post-collision line design include the implementation of a common dump for the wrong-sign charged particles of the coherent pairs and for the low-energy tails of the disrupted beam, as well as a significant reduction of the overall lattice length (allowing removal of the large refocusing quadrupoles). The thermal and mechanical stresses in the new exit window, 150 m downstream of the interaction point, were computed. We conclude that, despite the recent changes of the CLIC beam parameters and the necessary modifications of the post-collision line and its exit window, their performance is not significantly affected.

  16. Design of the extraction arc for the 2nd beam line of the free-electron laser FLASH

    International Nuclear Information System (INIS)

    Scholz, Matthias

    2014-01-01

    In this thesis, I deal with the design of the extraction arc for the second beam line of FLASH, an FEL (Free-Electron Laser) user facility at DESY Hamburg. Both beam lines will use the same linear accelerator and their separation will take place behind the last accelerating module. I present the constraints for the extraction arc given by the beam line layout of the existing machine, by the building environment of the new beam line and in particular, by coherent synchrotron radiation (CSR). The impact from CSR is presented, and I show how to mitigate these effects and what that means for the beam line design. The optimization of the extraction arc was done applying the downhill simplex algorithm which is presented, first in its basic form to explain the operation principle and then in a more advanced version as used in the applied program. I introduce in this thesis the final layout of the extraction arc including the following matching section. This layout fulfills all given constraints and can provide the required electron beam quality for FEL operation. In order to prove this, I present start-to-end simulations for different bunch charges and for two different wavelengths.

  17. Bayesian modelling of the emission spectrum of the Joint European Torus Lithium Beam Emission Spectroscopy system.

    Science.gov (United States)

    Kwak, Sehyun; Svensson, J; Brix, M; Ghim, Y-C

    2016-02-01

    A Bayesian model of the emission spectrum of the JET lithium beam has been developed to infer the intensity of the Li I (2p-2s) line radiation and associated uncertainties. The detected spectrum for each channel of the lithium beam emission spectroscopy system is here modelled by a single Li line modified by an instrumental function, Bremsstrahlung background, instrumental offset, and interference filter curve. Both the instrumental function and the interference filter curve are modelled with non-parametric Gaussian processes. All free parameters of the model, the intensities of the Li line, Bremsstrahlung background, and instrumental offset, are inferred using Bayesian probability theory with a Gaussian likelihood for photon statistics and electronic background noise. The prior distributions of the free parameters are chosen as Gaussians. Given these assumptions, the intensity of the Li line and corresponding uncertainties are analytically available using a Bayesian linear inversion technique. The proposed approach makes it possible to extract the intensity of Li line without doing a separate background subtraction through modulation of the Li beam.

  18. Modeling of an Adjustable Beam Solid State Light

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is for the development of a computational model of a prototype variable beam light source using optical modeling software, Zemax OpticStudio ®. The...

  19. First results from the high energy resolution photoemission beam line at ELETTRA

    International Nuclear Information System (INIS)

    Quaresima, C.; Astaldi, C.; Zacchigna, M.; Romanzin, L.; Savoia, A.

    1995-01-01

    We report the first results obtained from the high energy resolution beam line at the storage ring ELETTRA of Trieste. The beam line has been designed to perform photoemission experiments in the vacuum ultraviolet (VUV) and soft X-ray (SXR) energy range. The radiation source is an undulator which consists of three sections, with 36 periods and a period length of 12.5 cm. It allows scanning of an energy range 17-900 eV using the 1st, 3rd and 5th harmonics. The monochromator is a spherical grating type and the resolving power at 400 eV, estimated from the K-shell photoabsorption of the N 2 molecule is well above 10 000. The spectra are better than any other spectra taken while operating with high flux, i.e. first order diffraction and grating not masked. Measurements taken at the oxygen and neon K-edges, the argon L 2,3 edges and of the helium double ionization spectra, indicate that the resolution is excellent from 65 to 870 eV. (orig.)

  20. Application of magnetically insulated transmission lines for high current, high voltage electron beam accelerators

    International Nuclear Information System (INIS)

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1993-01-01

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently the authors used a MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r b < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v perpendicular/c = β perpendicular ≤ 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. The authors' success with the MITL technology led them to investigate the application to higher energy accelerator designs. They have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30-50-ns FWHM output pulse

  1. Application of Magnetically Insulated Transmission Lines for high current, high voltage electron beam accelerators

    International Nuclear Information System (INIS)

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1991-01-01

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently we used at MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r ρ < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v perpendicular/c = β perpendicular ≤ 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. Our success with the MITL technology led us to investigate the application to higher energy accelerator designs. We have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30--50 ns FWHM output pulse. 10 refs

  2. Multiobjective optimizations of a novel cryocooled dc gun based ultrafast electron diffraction beam line

    Science.gov (United States)

    Gulliford, Colwyn; Bartnik, Adam; Bazarov, Ivan

    2016-09-01

    We present the results of multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line utilizing a 225 kV dc gun with a novel cryocooled photocathode system and buncher cavity. Optimizations of the transverse projected emittance as a function of bunch charge are presented and discussed in terms of the scaling laws derived in the charge saturation limit. Additionally, optimization of the transverse coherence length as a function of final rms bunch length at the sample location have been performed for three different sample radii: 50, 100, and 200 μ m , for two final bunch charges: 1 05 electrons (16 fC) and 1 06 electrons (160 fC). Example optimal solutions are analyzed, and the effects of disordered induced heating estimated. In particular, a relative coherence length of Lc ,x/σx=0.27 nm /μ m was obtained for a final bunch charge of 1 05 electrons and final bunch length of σt≈100 fs . For a final charge of 1 06 electrons the cryogun produces Lc ,x/σx≈0.1 nm /μ m for σt≈100 - 200 fs and σx≥50 μ m . These results demonstrate the viability of using genetic algorithms in the design and operation of ultrafast electron diffraction beam lines.

  3. Contrast of HOLZ lines in energy-filtered convergent-beam electron diffraction patterns from silicon

    International Nuclear Information System (INIS)

    Lehmpfuhl, G.; Krahl, D.; Uchida, Y.

    1995-01-01

    Higher-order Laue-zone (HOLZ) lines were investigated in convergent-beam electron diffraction patterns from silicon near the low-indexed zone axes [100], [110] and [111]. The visibility of these lines depends on the effective structure potentials of the reflections from the first Laue zone depending on their Debye-Waller factor. The contrast of the HOLZ lines is strongly reduced by inelastically scattered electrons. They can be excluded by an imaging Ω filter for energy losses above 2 eV. The diffraction patterns were compared with many-beam calculations. Without absorption, an excellent agreement could be achieved for the [111] and [100] zone axes, while the simulation of the [110] zone-axis pattern needed a calculation with absorption. The reason for this observation is explained in the Bloch-wave picture. Calculations with absorption, however, lead to artefacts in the intensity distribution of the [100] HOLZ pattern. In order to obtain agreement with the experiment, the Debye-Waller factor had to be modified in different ways for the different zone axes. This corresponds to a strong anisotropy of the Debye-Waller factor. To confirm this observation, the temperature dependence of the itensity distributions of the HOLZ patterns was investigated between 50 and 680 K. At room temperature, the parameter D in the Debye-Waller factor exp(-Ds 2 ) was determined as 0.13, 0.26 and 0.55 A 2 for the zone axes [100], [111] and [110], respectively. The reliability of the conclusions is discussed. (orig.)

  4. Beam model for non-planar orbits in synchrotrons

    International Nuclear Information System (INIS)

    Month, M.

    1984-01-01

    A framework has been developed for a beam model in the case of synchrotron orbits not confined to a plane. An appropriate moving reference system for the analysis of beam stability has been introduced. As examples of strong perturbations to median plane symmetry, two geometries for the overpass for the Tevatron collider are considered

  5. Beam model for non-planar orbits in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Month, M.

    1984-03-26

    A framework has been developed for a beam model in the case of synchrotron orbits not confined to a plane. An appropriate moving reference system for the analysis of beam stability has been introduced. As examples of strong perturbations to median plane symmetry, two geometries for the overpass for the Tevatron collider are considered.

  6. Artificial Neural Network Model for Low Strength RC Beam Shear ...

    African Journals Online (AJOL)

    This research was to investigate how the shear strength prediction of low strength reinforced concrete beams will improve under an ANN model. An existing database of 310 reinforced concrete beams without web reinforcement was divided into three sets of training, validation and testing. A total of 224 different architectural ...

  7. Calculation of benchmarks with a shear beam model

    NARCIS (Netherlands)

    Hendriks, M.A.N.; Boer, A.; Rots, J.G.; Ferreira, D.

    2015-01-01

    Fiber models for beam and shell elements allow for relatively rapid finite element analysis of concrete structures and structural elements. This project aims at the development of the formulation of such elements and a pilot implementation. Standard nonlinear fiber beam formulations do not account

  8. Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

    International Nuclear Information System (INIS)

    Hutton, R.D.

    1994-01-01

    As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal's photo multiplier tube (PMT)

  9. Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Hutton, R.D.

    1994-01-01

    As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal`s photo multiplier tube (PMT).

  10. SU-F-T-145: Modeling of a Proton Pencil Beam Partially Blocked by a Collimator

    International Nuclear Information System (INIS)

    Slopsema, R; Matysiak, W

    2016-01-01

    Purpose: To develop a mathematical model of the fluence distribution of a proton pencil beam that is partially blocked by a collimator. Methods: In one dimension, an exact analytical solution of the proton distribution behind a collimator edge was derived, taking the beam’s phase space, the edge position, and the scattering downstream of the collimator as input. Extension to two dimensions was achieved using a Clarkson-like Method: determine the radial distances from each calculation point to the collimator outline, calculate the beam’s phase space in the direction of each radial line, apply the one-dimensional model along each radial line, and sum the contributions. A Matlab implementation of the full model produced high-resolution distributions with relatively short calculation times (of about 2 ms per calculation point). The model was validated by comparison to Monte Carlo simulations for select pencil beam phase space distributions and collimator shapes. Results: Agreement between model and simulation confirm the exact mathematical solution of the one-dimensional model. In two dimensions the agreement is reasonable, but not exact, due to the approximations introduced in the Clarkson-like method. Conclusion: A model has been developed and validated that gives the lateral fluence distribution of a pencil beam beyond a collimator. Notably, this model does not include free parameters and the final fluence is completely determined by the phase space parameters of the beam, already existing in the treatment planning system, as well as both axial and lateral position of the aperture edge. As such, it can be incorporated in a full pencil-beam dose calculation algorithm allowing for the modeling of field-specific collimators in proton pencil beam scanning and, potentially, the optimization of collimator shape and/or pencil phase space in addition to the customary spot weight optimization.

  11. Comparison of Stabilization of Piezoelectric Euler-Bernoulli Beam Models

    NARCIS (Netherlands)

    de Jong, Matthias; Scherpen, Jacquelien M.A.; Morris, Kirsten

    2016-01-01

    Piezoelectric materials are used in many control and sensing applications via a strip of piezoelectric material also known as a piezoelectric beam. Applications can be vibration control in (complex) mechanical structures and on-line measurement or compensation in high-precision technology for shape

  12. Modelling pencil-beam divergence with the electron pencil-beam redefinition algorithm

    Science.gov (United States)

    Boyd, Robert A.; Hogstrom, Kenneth R.; White, R. Allen; Starkschall, George

    2001-11-01

    The electron pencil-beam redefinition algorithm (PBRA), which is used to calculate electron beam dose distributions, assumes that the virtual source of each pencil beam is identical to that of the broad beam incident on the patient. In the present work, a virtual source specific for each pencil beam is modelled by including the source distance as a pencil-beam parameter to be redefined with depth. To incorporate a variable pencil-beam source distance parameter, the transport equation was reformulated to explicitly model divergence resulting in the algorithm divPBRA. Allowing the virtual source position to vary with individual pencil beams is expected to better model the effects of heterogeneities on local electron fluence divergence (or convergence). Selected experiments from a measured data set developed at The University of Texas M D Anderson Cancer Center were used to evaluate the accuracy of the dose calculated using divPBRA. Results of the calculation showed that the theory accurately predicted the virtual source position in regions of side-scatter equilibrium and predicted reasonable virtual source positions in regions lacking side-scatter equilibrium (i.e. penumbra and in the vicinity and shadow of internal heterogeneities). Results of the evaluation showed the dose accuracy of divPBRA to be marginally better to that of PBRA, except in regions of extremely sharp dose perturbations, where the divPBRA calculations were significantly greater than the measured data. Dose calculations using divPBRA took 45% longer than those using PBRA. Therefore, we concluded that divPBRA offers no significant advantage over PBRA for the purposes of clinical treatment planning. However, the results were promising and divPBRA might prove useful if further modelling were to include large-angle scattering, low-energy delta rays and brehmsstrahlung.

  13. Modelling pencil-beam divergence with the electron pencil-beam redefinition algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, Robert A.; Hogstrom, Kenneth R.; Starkschall, George [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); White, R. Allen [Department of Biomathematics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

    2001-11-01

    The electron pencil-beam redefinition algorithm (PBRA), which is used to calculate electron beam dose distributions, assumes that the virtual source of each pencil beam is identical to that of the broad beam incident on the patient. In the present work, a virtual source specific for each pencil beam is modelled by including the source distance as a pencil-beam parameter to be redefined with depth. To incorporate a variable pencil-beam source distance parameter, the transport equation was reformulated to explicitly model divergence resulting in the algorithm divPBRA. Allowing the virtual source position to vary with individual pencil beams is expected to better model the effects of heterogeneities on local electron fluence divergence (or convergence). Selected experiments from a measured data set developed at The University of Texas M D Anderson Cancer Center were used to evaluate the accuracy of the dose calculated using divPBRA. Results of the calculation showed that the theory accurately predicted the virtual source position in regions of side-scatter equilibrium and predicted reasonable virtual source positions in regions lacking side-scatter equilibrium (i.e. penumbra and in the vicinity and shadow of internal heterogeneities). Results of the evaluation showed the dose accuracy of divPBRA to be marginally better to that of PBRA, except in regions of extremely sharp dose perturbations, where the divPBRA calculations were significantly greater than the measured data. Dose calculations using divPBRA took 45% longer than those using PBRA. Therefore, we concluded that divPBRA offers no significant advantage over PBRA for the purposes of clinical treatment planning. However, the results were promising and divPBRA might prove useful if further modelling were to include large-angle scattering, low-energy delta rays and brehmsstrahlung. (author)

  14. Modelling pencil-beam divergence with the electron pencil-beam redefinition algorithm.

    Science.gov (United States)

    Boyd, R A; Hogstrom, K R; White, R A; Starkschall, G

    2001-11-01

    The electron pencil-beam redefinition algorithm (PBRA), which is used to calculate electron beam dose distributions, assumes that the virtual source of each pencil beam is identical to that of the broad beam incident on the patient. In the present work, a virtual source specific for each pencil beam is modelled by including the source distance as a pencil-beam parameter to be redefined with depth. To incorporate a variable pencil-beam source distance parameter, the transport equation was reformulated to explicitly model divergence resulting in the algorithm divPBRA. Allowing the virtual source position to vary with individual pencil beams is expected to better model the effects of heterogeneities on local electron fluence divergence (or convergence). Selected experiments from a measured data set developed at The University of Texas M D Anderson Cancer Center were used to evaluate the accuracy of the dose calculated using divPBRA. Results of the calculation showed that the theory accurately predicted the virtual source position in regions of side-scatter equilibrium and predicted reasonable virtual source positions in regions lacking side-scatter equilibrium (i.e. penumbra and in the vicinity and shadow of internal heterogeneities). Results of the evaluation showed the dose accuracy of divPBRA to be marginally better to that of PBRA, except in regions of extremely sharp dose perturbations, where the divPBRA calculations were significantly greater than the measured data. Dose calculations using divPBRA took 45% longer than those using PBRA. Therefore, we concluded that divPBRA offers no significant advantage over PBRA for the purposes of clinical treatment planning. However, the results were promising and divPBRA might prove useful if further modelling were to include large-angle scattering, low-energy delta rays and brehmsstrahlung.

  15. A mechanical model for FRP-strengthened beams in bending

    Directory of Open Access Journals (Sweden)

    P. S. Valvo

    2012-10-01

    Full Text Available We analyse the problem of a simply supported beam, strengthened with a fibre-reinforced polymer (FRP strip bonded to its intrados and subjected to bending couples applied to its end sections. A mechanical model is proposed, whereby the beam and FRP strip are modelled according to classical beam theory, while the adhesive and its neighbouring layers are modelled as an interface having a piecewise linear constitutive law defined over three intervals (elastic response – softening response – debonding. The model is described by a set of differential equations with appropriate boundary conditions. An analytical solution to the problem is determined, including explicit expressions for the internal forces, displacements and interfacial stresses. The model predicts an overall non-linear mechanical response for the strengthened beam, ranging over several stages: from linearly elastic behaviour to damage, until the complete detachment of the FRP reinforcement.

  16. On beam models and their paraxial approximation

    Science.gov (United States)

    Waters, W. J.; King, B.

    2018-01-01

    We derive focused laser pulse solutions to the electromagnetic wave equation in vacuum. After reproducing beam and pulse expressions for the well-known paraxial Gaussian and axicon cases, we apply the method to analyse a laser beam with Lorentzian transverse momentum distribution. Whilst a paraxial approach has some success close to the focal axis and within a Rayleigh range of the focal spot, we find that it incorrectly predicts the transverse fall-off typical of a Lorentzian. Our vector-potential approach is particularly relevant to calculation of quantum electrodynamical processes in weak laser pulse backgrounds.

  17. Development of a New RF Finger concept for vacuum beam line interconnections

    CERN Document Server

    Garion, C; Rambeau, H

    2012-01-01

    RF contact fingers are primarily used as a transition element to absorb the thermal expansion of vacuum chambers during bake-out and also to compensate for mechanical tolerances. They have to carry the beam image current to avoid the generation of Higher Order Modes and to reduce beam impedances. They are usually made out of copper beryllium thin sheets and are therefore very fragile and critical components. In this paper, a robust design based on a deformable finger concept is proposed. It allows the compensation of large longitudinal movements and also defaults such as transverse offset, twist or bending. The concept of this new RF fingers is first explained, then the design of the component is presented. The mechanical study based on a highly non-linear Finite Element model is shown as well as preliminary tests, including fatigue assessment, carried out on prototypes.

  18. Multiobjective optimization design of an rf gun based electron diffraction beam line

    Science.gov (United States)

    Gulliford, Colwyn; Bartnik, Adam; Bazarov, Ivan; Maxson, Jared

    2017-03-01

    Multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line comprised of a 100 MV /m 1.6-cell normal conducting rf (NCRF) gun, as well as a nine-cell 2 π /3 bunching cavity placed between two solenoids, have been performed. These include optimization of the normalized transverse emittance as a function of bunch charge, as well as optimization of the transverse coherence length as a function of the rms bunch length of the beam at the sample location for a fixed charge of 1 06 electrons. Analysis of the resulting solutions is discussed in terms of the relevant scaling laws, and a detailed description of one of the resulting solutions from the coherence length optimizations is given. For a charge of 1 06 electrons and final beam sizes of σx≥25 μ m and σt≈5 fs , we found a relative coherence length of Lc ,x/σx≈0.07 using direct optimization of the coherence length. Additionally, based on optimizations of the emittance as a function of final bunch length, we estimate the relative coherence length for bunch lengths of 30 and 100 fs to be roughly 0.1 and 0.2 nm /μ m , respectively. Finally, using the scaling of the optimal emittance with bunch charge, for a charge of 1 05 electrons, we estimate relative coherence lengths of 0.3, 0.5, and 0.92 nm /μ m for final bunch lengths of 5, 30 and 100 fs, respectively.

  19. Multiobjective optimization design of an rf gun based electron diffraction beam line

    Directory of Open Access Journals (Sweden)

    Colwyn Gulliford

    2017-03-01

    Full Text Available Multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line comprised of a 100  MV/m 1.6-cell normal conducting rf (NCRF gun, as well as a nine-cell 2π/3 bunching cavity placed between two solenoids, have been performed. These include optimization of the normalized transverse emittance as a function of bunch charge, as well as optimization of the transverse coherence length as a function of the rms bunch length of the beam at the sample location for a fixed charge of 10^{6} electrons. Analysis of the resulting solutions is discussed in terms of the relevant scaling laws, and a detailed description of one of the resulting solutions from the coherence length optimizations is given. For a charge of 10^{6} electrons and final beam sizes of σ_{x}≥25  μm and σ_{t}≈5  fs, we found a relative coherence length of L_{c,x}/σ_{x}≈0.07 using direct optimization of the coherence length. Additionally, based on optimizations of the emittance as a function of final bunch length, we estimate the relative coherence length for bunch lengths of 30 and 100 fs to be roughly 0.1 and 0.2  nm/μm, respectively. Finally, using the scaling of the optimal emittance with bunch charge, for a charge of 10^{5} electrons, we estimate relative coherence lengths of 0.3, 0.5, and 0.92  nm/μm for final bunch lengths of 5, 30 and 100 fs, respectively.

  20. The pulsed power converters of the beam transfer lines at DAPHNE/INFL-LNF

    CERN Document Server

    Sanelli, C; Völker, F V

    1998-01-01

    DAPHNE, the phi-factory 510 MeV electron/positron (e±) collider at LNF (Laboratori Nazionali di Frascati), consists of a full energy linac, an accumulator ring (AR) and two storage rings (SRs). The tr ansfer line (TL) conveys the beams from the linac to the AR and thence to the SRs. The TL includes three pulsed magnets. One of them is excited by a special ± 650 A, 55 kW power supply with resonant f ast current polarity inversion within 30 ms. The other two are fed by capacitor discharge power supplies, providing half-sine current pulses of ± 650 A / 30 ms and ± 230 A peak / 20 ms duration. The T L operation and the pulsed magnets are briefly described. The design and topology of the power supplies are presented. Some current and voltage waveforms illustrate the functioning of this already ins talled and fully operational equipment.

  1. Detector Response and Beam Line Transmission Measurements with Far-Infrared Radiation

    CERN Document Server

    Grimm, O; Fröhlich, L

    2005-01-01

    Various activities at the TTF linear accelerator at DESY, Hamburg, that drives the VUV-FEL are geared towards measuring the longitudinal charge distribution of electron bunches with coherent far-infrared radiation. Examples are beam lines transporting synchrotron or transition radiation to interferometers mounted inside or outside the tunnel, and studies of single-shot grating spectrometers. All such approaches require a good understanding of the radiation generation and transport mechanism and of the detector characteristics to extract useful information on the charge distribution. Simulations and measurements of the expected transverse intensity distribution and polarization of synchrotron radiation emitted at the first bunch compressor of TTF have been performed. The transverse intensity scanning provided for the first time at DESY a visual image of the footprint of terahertz radiation. Detector response measurements have been performed at the FELIX facility, Netherlands, for wavelengths between 100-160 mi...

  2. Operating experience with LAMPF main beam lines instrumentation and control system

    International Nuclear Information System (INIS)

    van Dyck, O.B.; Harvey, A.; Howard, H.H.; Roeder, D.L.

    1975-01-01

    Instrumentation and control (I and C) for the Los Alamos Clinton P. Anderson Meson Physics Facility (LAMPF) main beam line is based upon central computer control through remote stations which provide input and output to most devices. Operating experience shows that the ability of the computer to give high-quality graphical presentation of the measurements enhances operator performance and instrument usefulness. Experience also shows that operator efficiency degrades rapidly with increasing instrument response time, that is, with increasing delay between the time a control is changed and the result can be observed. For this reason, instrumentation upgrade includes speeding up data acquisition and display times to under 10 s. Similarly, television-viewed phosphors are being retained where possible since their instantaneous response is very useful. Other upgrading of the instrumentation system is planned to improve data accuracy, reliability, redundancy, and instrument radiation tolerance. Past experience is being applied in adding or relocating devices to simplify tuning procedures. (U.S.)

  3. Ibaraki prefecture's neutron beam lines in J-PARC and outline of industrial applications

    International Nuclear Information System (INIS)

    Hayashi, Makoto

    2008-01-01

    The outlines of J-PARC and Ibaraki Prefecture's two neutron facilities for the structural analysis of materials and living materials in J-PARC/MLF (Materials and Life Science Facility) are described. The status of the industrial use of these facilities is also mentioned. The building of J-PARC/MLF was completed and about ten sets of neutron apparatuses have been in preparation. The round-table conference of MLF users started in the beginning of September and is in progress toward the public use scheduled in December, 2008. The detailed design of these two neutron facilities for industrial use was completed and its greater part has been produced. The uses of Ibaraki Prefecture's beam lines will produce the materials with highly additional values and with highly reliable structures by the measurement of residual stresses, etc. Furthermore, these uses may be connected to the development of medicine for incurable diseases. (M.H.)

  4. Artificial intelligence research in particle accelerator control systems for beam line tuning

    Energy Technology Data Exchange (ETDEWEB)

    Pieck, Martin [Los Alamos National Laboratory

    2008-01-01

    Tuning particle accelerators is time consuming and expensive, with a number of inherently non-linear interactions between system components. Conventional control methods have not been successful in this domain and the result is constant and expensive monitoring of the systems by human operators. This is particularly true for the start-up and conditioning phase after a maintenance period or an unexpected fault. In turn, this often requires a step-by-step restart of the accelerator. Surprisingly few attempts have been made to apply intelligent accelerator control techniques to help with beam tuning, fault detection, and fault recovery problems. The reason for that might be that accelerator facilities are rare and difficult to understand systems that require detailed expert knowledge about the underlying physics as well as months if not years of experience to understand the relationship between individual components, particularly if they are geographically disjoint. This paper will give an overview about the research effort in the accelerator community that has been dedicated to the use of artificial intelligence methods for accelerator beam line tuning.

  5. On models of layered piezoelectric beams for passive vibration control

    Science.gov (United States)

    Maurini, C.; dell'Isola, F.; Pouget, J.

    2004-06-01

    In this paper models of layered piezoelectric beams are discussed. The attention is focused on the analysis of the assumptions on transversal stress and strain distribution and their influence on the deduction of the beam constitutive equations from a three dimensional description. A model accounting for non trivial transversal interactions between different layers is deduced from a mixed variational formulation where non-local conditions on transversal stress are enforced by Lagrange multipliers method. The fully coupled electromechanical nature of the system is described. For a sandwich piezoelectric beam, analytical expressions of the beam constitutive coefficients are provided and comparisons to standard modelling approaches are presented. Finally, the fundamental features of the proposed model are highlighted by presenting the through-the-thickness distribution of the 3D state fields.

  6. Modeling of Electromagnetic Wave Propagation with Tapered Transmission Line

    Science.gov (United States)

    Lee, Kun-A.; Ko, Kwang-Cheol

    2012-09-01

    Tapered transmission line was used for impedance matching, for high voltage pulse, and atmospheric medium is applied to characteristic equation of tapered transmission line and reflection coefficient so that nonlinear load and circuit modeling of atmospheric medium was simulated by electromagnetic transient program (EMTP). A characteristic of atmospheric medium and Time delay are decided by inductance and capacitance of tapered transmission line. For electromagnetic wave propagation modeling, in this paper, tapered transmission line is implemented. It is difficult to model tapered transmission line directly. Other transmission line that can be expressed by the circuit is used. So object of this paper is efficient modeling of tapered transmission line.

  7. Multiobjective optimizations of a novel cryocooled dc gun based ultrafast electron diffraction beam line

    Directory of Open Access Journals (Sweden)

    Colwyn Gulliford

    2016-09-01

    Full Text Available We present the results of multiobjective genetic algorithm optimizations of a single-shot ultrafast electron diffraction beam line utilizing a 225 kV dc gun with a novel cryocooled photocathode system and buncher cavity. Optimizations of the transverse projected emittance as a function of bunch charge are presented and discussed in terms of the scaling laws derived in the charge saturation limit. Additionally, optimization of the transverse coherence length as a function of final rms bunch length at the sample location have been performed for three different sample radii: 50, 100, and 200  μm, for two final bunch charges: 10^{5} electrons (16 fC and 10^{6} electrons (160 fC. Example optimal solutions are analyzed, and the effects of disordered induced heating estimated. In particular, a relative coherence length of L_{c,x}/σ_{x}=0.27  nm/μm was obtained for a final bunch charge of 10^{5} electrons and final bunch length of σ_{t}≈100  fs. For a final charge of 10^{6} electrons the cryogun produces L_{c,x}/σ_{x}≈0.1  nm/μm for σ_{t}≈100–200  fs and σ_{x}≥50  μm. These results demonstrate the viability of using genetic algorithms in the design and operation of ultrafast electron diffraction beam lines.

  8. RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

    International Nuclear Information System (INIS)

    Wang Tiegu; Huang Qunce; Feng Weisen

    2007-01-01

    Two types of markers-random amplified polymorphic DNA (RAPD) and simple sequence repeat DNA (SSR)-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA (Unweighted Pair-group Method with Arithmetic averaging) algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, s1, opt-16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 (Xgwm261), Rht-B1b, and Rht-D1b, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning

  9. Optics measurements and transfer line matching for the SPS injection of the CERN Multi-Turn Extraction beam

    CERN Document Server

    Benedetto, E; Cettour Cave, S; Follin, F; Gilardoni, S; Giovannozzi, M; Roncarolo, F

    2010-01-01

    Dispersion and beam optics measurements were carried out in the transfer line between the CERN PS and SPS for the new Multi-Turn Extraction beam. Since the extraction conditions of the four islands and the core are different and strongly dependent on the non-linear effects used to split the beam in the transverse plane, a special care was taken during the measurement campaigns. Furthermore, an appropriate strategy was devised to minimize the overall optical mismatch at SPS injection. All this led to a new optical configuration that will be presented in the paper.

  10. Measurement of in-phantom neutron flux and gamma dose in Tehran research reactor boron neutron capture therapy beam line.

    Science.gov (United States)

    Bavarnegin, Elham; Sadremomtaz, Alireza; Khalafi, Hossein; Kasesaz, Yaser

    2016-01-01

    Determination of in-phantom quality factors of Tehran research reactor (TRR) boron neutron capture therapy (BNCT) beam. The doses from thermal neutron reactions with 14N and 10B are calculated by kinetic energy released per unit mass approach, after measuring thermal neutron flux using neutron activation technique. Gamma dose is measured using TLD-700 dosimeter. Different dose components have been measured in a head phantom which has been designed and constructed for BNCT purpose in TRR. Different in-phantom beam quality factors have also been determined. This study demonstrates that the TRR BNCT beam line has potential for treatment of superficial tumors.

  11. Multiobjective Fuzzy Mixed Assembly Line Sequencing Optimization Model

    OpenAIRE

    Tahriri, Farzad; Zawiah Md Dawal, Siti; Taha, Zahari

    2014-01-01

    It can be deduced from previous studies that there exists a research gap in assembly line sequencing optimization model for mixed-model production lines. In particular, there is a lack of studies which focus on the integration between job shop and assembly lines using fuzzy techniques. Hence, this paper is aimed at addressing the multiobjective mixed-model assembly line sequencing problem by integrating job shop and assembly production lines for factories with modular layouts. The primary go...

  12. The EPICS-based remote control system for muon beam line devices at J-PARC MUSE

    Energy Technology Data Exchange (ETDEWEB)

    Ito, T U; Higemoto, W [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Nakahara, K; Fujimori, H; Kobayashi, Y; Miyake, Y [Muon Science Laboratory, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Kawase, M, E-mail: ito.takashi15@jaea.go.j [J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)

    2010-04-01

    The remote control system for muon beam line devices of J-PARC MUSE has been developed with the Experimental Physics and Industrial Control System (EPICS). The EPICS input/output controller was installed in standard Linux PCs for slow control of the devices. Power supplies for 21 magnetic elements and four slit controllers for the decay-surface muon beam line in the Materials and Life Science Experimental Facility are now accessible via Ethernet from a graphical user interface which has been composed using the Motif Editor and Display Manger.

  13. An extended range soft X-ray beam line for the 1 GeV storage ring Aladdin

    International Nuclear Information System (INIS)

    Hulbert, S.L.; Stott, J.P.; Brown, F.C.

    1983-01-01

    The design and implementation of a soft X-ray beam line on the new 1 GeV storage ring Aladdin in Stoughton, Wisconsin is discussed. The beam line consists of a long horizontally focussing collection mirror, an extended range (50-1500 eV) grasshopper monochromator, an ellipsoidal refocussing mirror, and a photoemission chamber. Also discussed are the factors considered in matching the monochromator to the storage ring, flux and performance expectations, and the results of a ray tracing analysis. (orig.)

  14. Large deflection of viscoelastic beams using fractional derivative model

    International Nuclear Information System (INIS)

    Bahranini, Seyed Masoud Sotoodeh; Eghtesad, Mohammad; Ghavanloo, Esmaeal; Farid, Mehrdad

    2013-01-01

    This paper deals with large deflection of viscoelastic beams using a fractional derivative model. For this purpose, a nonlinear finite element formulation of viscoelastic beams in conjunction with the fractional derivative constitutive equations has been developed. The four-parameter fractional derivative model has been used to describe the constitutive equations. The deflected configuration for a uniform beam with different boundary conditions and loads is presented. The effect of the order of fractional derivative on the large deflection of the cantilever viscoelastic beam, is investigated after 10, 100, and 1000 hours. The main contribution of this paper is finite element implementation for nonlinear analysis of viscoelastic fractional model using the storage of both strain and stress histories. The validity of the present analysis is confirmed by comparing the results with those found in the literature.

  15. Beam dynamics studies to develop LHC luminosity model

    CERN Document Server

    Campogiani, Giovanna; Papaphilippou, Ioannis

    The thesis project aims at studying the different physical processes that are impacting luminosity, one of the key figures of merit of a collider operation. In particular the project focuses on extracting the most relevant parameters for the high-energy part of the model, which is mostly dominated by the beam-beam effect. LHC luminosity is degraded by parasitic collisions that reduce the beam lifetime and the particles stability in the collider. This instability is due to the non-linear effects of one beam electromagnetic field on another in the interaction region. Such parasitic encounters can be as many as 16 per interaction region, piling up to around 180 000 per second. Our goal is to study the evolution of charge density distribution in the beam, by tracking particles through a symplectic integrator that includes the beam-beam effect. In particular we want to obtain data on the halo particles, which are more sensible to instability, to better characterise the beam lifetime and monitor the luminosity evol...

  16. Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

    CERN Document Server

    Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

    2014-01-01

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  17. The Structured Intuitive Model for Product Line Economics (SIMPLE)

    National Research Council Canada - National Science Library

    Clements, Paul C; McGregor, John D; Cohen, Sholom G

    2005-01-01

    .... This report presents the Structured Intuitive Model of Product Line Economics (SIMPLE), a general-purpose business model that supports the estimation of the costs and benefits in a product line development organization...

  18. Model Independent Analysis of Beam Centroid Dynamics in Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chun-xi

    2003-04-21

    Fundamental issues in Beam-Position-Monitor (BPM)-based beam dynamics observations are studied in this dissertation. The major topic is the Model-Independent Analysis (MIA) of beam centroid dynamics. Conventional beam dynamics analysis requires a certain machine model, which itself of ten needs to be refined by beam measurements. Instead of using any particular machine model, MIA relies on a statistical analysis of the vast amount of BPM data that often can be collected non-invasively during normal machine operation. There are two major parts in MIA. One is noise reduction and degrees-of-freedom analysis using a singular value decomposition of a BPM-data matrix, which constitutes a principal component analysis of BPM data. The other is a physical base decomposition of the BPM-data matrix based on the time structure of pulse-by-pulse beam and/or machine parameters. The combination of these two methods allows one to break the resolution limit set by individual BPMs and observe beam dynamics at more accurate levels. A physical base decomposition is particularly useful for understanding various beam dynamics issues. MIA improves observation and analysis of beam dynamics and thus leads to better understanding and control of beams in both linacs and rings. The statistical nature of MIA makes it potentially useful in other fields. Another important topic discussed in this dissertation is the measurement of a nonlinear Poincare section (one-turn) map in circular accelerators. The beam dynamics in a ring is intrinsically nonlinear. In fact, nonlinearities are a major factor that limits stability and influences the dynamics of halos. The Poincare section map plays a basic role in characterizing and analyzing such a periodic nonlinear system. Although many kinds of nonlinear beam dynamics experiments have been conducted, no direct measurement of a nonlinear map has been reported for a ring in normal operation mode. This dissertation analyzes various issues concerning map

  19. Model Independent Analysis of Beam Centroid Dynamics in Accelerators

    International Nuclear Information System (INIS)

    Wang, Chun-xi

    2003-01-01

    Fundamental issues in Beam-Position-Monitor (BPM)-based beam dynamics observations are studied in this dissertation. The major topic is the Model-Independent Analysis (MIA) of beam centroid dynamics. Conventional beam dynamics analysis requires a certain machine model, which itself of ten needs to be refined by beam measurements. Instead of using any particular machine model, MIA relies on a statistical analysis of the vast amount of BPM data that often can be collected non-invasively during normal machine operation. There are two major parts in MIA. One is noise reduction and degrees-of-freedom analysis using a singular value decomposition of a BPM-data matrix, which constitutes a principal component analysis of BPM data. The other is a physical base decomposition of the BPM-data matrix based on the time structure of pulse-by-pulse beam and/or machine parameters. The combination of these two methods allows one to break the resolution limit set by individual BPMs and observe beam dynamics at more accurate levels. A physical base decomposition is particularly useful for understanding various beam dynamics issues. MIA improves observation and analysis of beam dynamics and thus leads to better understanding and control of beams in both linacs and rings. The statistical nature of MIA makes it potentially useful in other fields. Another important topic discussed in this dissertation is the measurement of a nonlinear Poincare section (one-turn) map in circular accelerators. The beam dynamics in a ring is intrinsically nonlinear. In fact, nonlinearities are a major factor that limits stability and influences the dynamics of halos. The Poincare section map plays a basic role in characterizing and analyzing such a periodic nonlinear system. Although many kinds of nonlinear beam dynamics experiments have been conducted, no direct measurement of a nonlinear map has been reported for a ring in normal operation mode. This dissertation analyzes various issues concerning map

  20. The tension adjuster used at the work line of electron beam radiation cross-linking wire and cable

    International Nuclear Information System (INIS)

    Zhang Yingfa; Liu Zhenhao; Yin Xuejun

    1999-01-01

    The tension adjuster is an important equipment in the transport system at the work line of electron beam radiation cross-linking wire and cable to realize the velocity synchronism. There are many kinds of the adjuster. By putting various adjusters together properly, the authors can keep the line work stable and raise the quality of the product. Two kinds of standing adjuster and their mechanism are introduced. Also the corresponding figures and formulas are shown

  1. High peak current operation of x-ray free-electron laser multiple beam lines by suppressing coherent synchrotron radiation effects

    Science.gov (United States)

    Hara, Toru; Kondo, Chikara; Inagaki, Takahiro; Togawa, Kazuaki; Fukami, Kenji; Nakazawa, Shingo; Hasegawa, Taichi; Morimoto, Osamu; Yoshioka, Masamichi; Maesaka, Hirokazu; Otake, Yuji; Tanaka, Hitoshi

    2018-04-01

    The parallel operation of multiple beam lines is an important means to expand the opportunity of user experiments at x-ray free-electron laser (XFEL) facilities. At SPring-8 Angstrom free-electron laser (SACLA), the multi-beam-line operation had been tested using two beam lines, but transverse coherent synchrotron radiation (CSR) effects at a dogleg beam transport severely limited the laser performance. To suppress the CSR effects, a new beam optics based on two double bend achromat (DBA) structures was introduced for the dogleg. After the replacement of the beam optics, high peak current bunches of more than 10 kA are now stably transported through the dogleg and the laser pulse output is increased by a factor of 2-3. In the multi-beam-line operation of SACLA, the electron beam parameters, such as the beam energy and peak current, can be adjusted independently for each beam line. Thus the laser output can be optimized and wide spectral tunability is ensured for all beam lines.

  2. Predictive models for moving contact line flows

    Science.gov (United States)

    Rame, Enrique; Garoff, Stephen

    2003-01-01

    Modeling flows with moving contact lines poses the formidable challenge that the usual assumptions of Newtonian fluid and no-slip condition give rise to a well-known singularity. This singularity prevents one from satisfying the contact angle condition to compute the shape of the fluid-fluid interface, a crucial calculation without which design parameters such as the pressure drop needed to move an immiscible 2-fluid system through a solid matrix cannot be evaluated. Some progress has been made for low Capillary number spreading flows. Combining experimental measurements of fluid-fluid interfaces very near the moving contact line with an analytical expression for the interface shape, we can determine a parameter that forms a boundary condition for the macroscopic interface shape when Ca much les than l. This parameter, which plays the role of an "apparent" or macroscopic dynamic contact angle, is shown by the theory to depend on the system geometry through the macroscopic length scale. This theoretically established dependence on geometry allows this parameter to be "transferable" from the geometry of the measurement to any other geometry involving the same material system. Unfortunately this prediction of the theory cannot be tested on Earth.

  3. Tip vortices in the actuator line model

    Science.gov (United States)

    Martinez, Luis; Meneveau, Charles

    2017-11-01

    The actuator line model (ALM) is a widely used tool to represent the wind turbine blades in computational fluid dynamics without the need to resolve the full geometry of the blades. The ALM can be optimized to represent the `correct' aerodynamics of the blades by choosing an appropriate smearing length scale ɛ. This appropriate length scale creates a tip vortex which induces a downwash near the tip of the blade. A theoretical frame-work is used to establish a solution to the induced velocity created by a tip vortex as a function of the smearing length scale ɛ. A correction is presented which allows the use of a non-optimal smearing length scale but still provides the downwash which would be induced using the optimal length scale. Thanks to the National Science Foundation (NSF) who provided financial support for this research via Grants IGERT 0801471, IIA-1243482 (the WINDINSPIRE project) and ECCS-1230788.

  4. Analytical model of impedance in elliptical beam pipes

    CERN Document Server

    Pesah, Arthur Chalom

    2017-01-01

    Beam instabilities are among the main limitations in building higher intensity accelerators. Having a good impedance model for every accelerators is necessary in order to build components that minimize the probability of instabilities caused by the interaction beam-environment and to understand what piece to change in case of intensity increasing. Most of accelerator components have their impedance simulated with finite elements method (using softwares like CST Studio), but simple components such as circular or flat pipes are modeled analytically, with a decreasing computation time and an increasing precision compared to their simulated model. Elliptical beam pipes, while being a simple component present in some accelerators, still misses a good analytical model working for the hole range of velocities and frequencies. In this report, we present a general framework to study the impedance of elliptical pipes analytically. We developed a model for both longitudinal and transverse impedance, first in the case of...

  5. Commissioning of a compact laser-based proton beam line for high intensity bunches around 10Â MeV

    Science.gov (United States)

    Busold, S.; Schumacher, D.; Deppert, O.; Brabetz, C.; Kroll, F.; Blažević, A.; Bagnoud, V.; Roth, M.

    2014-03-01

    We report on the first results of experiments with a new laser-based proton beam line at the GSI accelerator facility in Darmstadt. It delivers high current bunches at proton energies around 9.6 MeV, containing more than 109 particles in less than 10 ns and with tunable energy spread down to 2.7% (ΔE/E0 at FWHM). A target normal sheath acceleration stage serves as a proton source and a pulsed solenoid provides for beam collimation and energy selection. Finally a synchronous radio frequency (rf) field is applied via a rf cavity for energy compression at a synchronous phase of -90 deg. The proton bunch is characterized at the end of the very compact beam line, only 3 m behind the laser matter interaction point, which defines the particle source.

  6. Commissioning of a compact laser-based proton beam line for high intensity bunches around 10 MeV

    Directory of Open Access Journals (Sweden)

    S. Busold

    2014-03-01

    Full Text Available We report on the first results of experiments with a new laser-based proton beam line at the GSI accelerator facility in Darmstadt. It delivers high current bunches at proton energies around 9.6 MeV, containing more than 10^{9} particles in less than 10 ns and with tunable energy spread down to 2.7% (ΔE/E_{0} at FWHM. A target normal sheath acceleration stage serves as a proton source and a pulsed solenoid provides for beam collimation and energy selection. Finally a synchronous radio frequency (rf field is applied via a rf cavity for energy compression at a synchronous phase of -90  deg. The proton bunch is characterized at the end of the very compact beam line, only 3 m behind the laser matter interaction point, which defines the particle source.

  7. Tertiary particle production and target optimization of the H2 beam line in the SPS North Area

    CERN Document Server

    Tellander, Felix

    2016-01-01

    H2 beam line of SPS North Area is a high energy, high resolution and multipurpose particle beam line. It is able to transport secondary hadron and pure electron beams with momenta between 10 and 400 GeV/c to be exploited by several different experiments. In this work, tertiary particle production from a secondary target placed in the line is studied. The introduction of this “filter” target enhances the middle to low momentum hadron (20 - 60 GeV/c) and electron production. In this work, a systematic Monte Carlo simulation study using a GEANT 4 based package, G4beamline, has been performed in order to investigate the tertiary particle production from several different targets. More specifically, Cu, W and polyethylene targets with different thicknesses have been studied. The proton over pi+ ratio is of particular interest, as well as the optimal electron production for several momenta. The present work will act as a reference to be used by the future test-beam users of the line as an indication of the expe...

  8. Cell survival in carbon beams - comparison of amorphous track model predictions

    DEFF Research Database (Denmark)

    Grzanka, L.; Greilich, S.; Korcyl, M.

    distribution models, and gamma response models was developed. This software can be used for direct numerical comparison between the models, submodels and their parameters and experimental data. In the present paper, we look at 10%-survival data from cell lines irradiated in vitro with carbon and proton beams...... neutrons, stopped pions, and heavy ion beams. Nucl Instrum Meth. 1973;111:93-116. 2.Weyrather WK, Kraft G. RBE of carbon ions: experimental data and the strategy of RBE calculation for treatment planning. Radiother Oncol. 2004;73(Suppl 2):161-9. 3.Greilich S, Grzanka L, Bassler N, Andersen CE, Jäkel O...... irradiation. The aim of this paper is to compare the predictions from different amorphous approaches found in the literature - more specifically the phenomenological, analytical model by Katz and co-workers [1] and a Monte-Carlo based full as implemented for example in the local effect model by Scholz et al...

  9. Therapeutic study of proton beam in vascular disease animal models

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. M.; Jang, K. H.; Kim, M. J.; Choi, J. H. [Kyungpook National University, Daegu (Korea, Republic of)

    2010-04-15

    We previously reported that proton beam inhibited angiogenic vessels in zebrafish and that proton induced cancer cell apoptosis via p53 induction as well as caspase-3 activity. In this study, we performed to identity the effect of candidate chemicals on the angiogenic inhibition in vitro and in vivo (zebrafish Flk1:EGFP transgenic fish). And we treated small cell lung adenocarcinoma cell line, A549 cells with proton beam in combination with angiogenic inhibitors we found in this study. By the MTT assay, we performed cell viability assay with cancer cells and we investigated that HIF-1{alpha} induction by proton beam by the western blot analysis. We found novel anti-angiogenic chemicals from traditional herb. That is decursin, and glyceollins from the Angelica gigas, and soy bean. Decrusin and glyceollins inhibited VEGF- or bFGF-induced endothelial cell proliferation, migration and zebrafish microvessel development. Moreover, glyceollins inhibited hypoxia-induced HIF-1{alpha} in a dose dependent manner. However, proton beam itself did not induce HIF-1{alpha} whereas it increased HIF-1{alpha} stability under hypoxia. Even proton beam induced cell death of A549 small cell lung carcinoma cells but the combination of decrusin or glyceollins did not increase the cancer cell death

  10. Therapeutic study of proton beam in vascular disease animal models

    International Nuclear Information System (INIS)

    Lee, Y. M.; Jang, K. H.; Kim, M. J.; Choi, J. H.

    2010-04-01

    We previously reported that proton beam inhibited angiogenic vessels in zebrafish and that proton induced cancer cell apoptosis via p53 induction as well as caspase-3 activity. In this study, we performed to identity the effect of candidate chemicals on the angiogenic inhibition in vitro and in vivo (zebrafish Flk1:EGFP transgenic fish). And we treated small cell lung adenocarcinoma cell line, A549 cells with proton beam in combination with angiogenic inhibitors we found in this study. By the MTT assay, we performed cell viability assay with cancer cells and we investigated that HIF-1α induction by proton beam by the western blot analysis. We found novel anti-angiogenic chemicals from traditional herb. That is decursin, and glyceollins from the Angelica gigas, and soy bean. Decrusin and glyceollins inhibited VEGF- or bFGF-induced endothelial cell proliferation, migration and zebrafish microvessel development. Moreover, glyceollins inhibited hypoxia-induced HIF-1α in a dose dependent manner. However, proton beam itself did not induce HIF-1α whereas it increased HIF-1α stability under hypoxia. Even proton beam induced cell death of A549 small cell lung carcinoma cells but the combination of decrusin or glyceollins did not increase the cancer cell death

  11. Pulsar average wave forms and hollow-cone beam models

    Science.gov (United States)

    Backer, D. C.

    1976-01-01

    Pulsar wave forms have been analyzed from observations conducted over a wide radio-frequency range to assess the wave-form morphologies and to measure wave-form widths. The results of the analysis compare favorably with the predictions of a model with a hollow-cone beam of fixed dimensions and with random orientation of both the observer and the cone axis with respect to the pulsar spin axis. A class of three-component wave forms is included in the model by adding a central pencil beam to the hollow-cone hypothesis. The consequences of a number of discrepancies between observations and quantitative predictions of the model are discussed.

  12. A new beam emission polarimetry diagnostic for measuring the magnetic field line angle at the plasma edge of ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Viezzer, E., E-mail: eleonora.viezzer@ipp.mpg.de, E-mail: eviezzer@us.es [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany); Department of Atomic, Molecular, and Nuclear Physics, University of Seville, Avda. Reina Mercedes, 41012 Seville (Spain); Dux, R.; Dunne, M. G. [Max-Planck-Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching (Germany)

    2016-11-15

    A new edge beam emission polarimetry diagnostic dedicated to the measurement of the magnetic field line angle has been installed on the ASDEX Upgrade tokamak. The new diagnostic relies on the motional Stark effect and is based on the simultaneous measurement of the polarization direction of the linearly polarized π (parallel to the electric field) and σ (perpendicular to the electric field) lines of the Balmer line D{sub α}. The technical properties of the system are described. The calibration procedures are discussed and first measurements are presented.

  13. A new beam emission polarimetry diagnostic for measuring the magnetic field line angle at the plasma edge of ASDEX Upgrade.

    Science.gov (United States)

    Viezzer, E; Dux, R; Dunne, M G

    2016-11-01

    A new edge beam emission polarimetry diagnostic dedicated to the measurement of the magnetic field line angle has been installed on the ASDEX Upgrade tokamak. The new diagnostic relies on the motional Stark effect and is based on the simultaneous measurement of the polarization direction of the linearly polarized π (parallel to the electric field) and σ (perpendicular to the electric field) lines of the Balmer line D α . The technical properties of the system are described. The calibration procedures are discussed and first measurements are presented.

  14. Design Study of a 100 GeV Beam Transfer Line from the SPS for a Short Baseline Neutrino Facility

    CERN Document Server

    Bartmann, W; Kosmicki, A; Kowalska, M; Velotti, F

    2013-01-01

    A short baseline neutrino facility at CERN is presently under study. It is considered to extract a 100 GeV beam from the second long straight section of the SPS into the existing transfer channel TT20, which leads to the North Area experimental zone. A new transfer line would branch off the existing TT20 line around 600 m downstream of the extraction, followed by an S-shaped horizontal bending arc to direct the beam with the correct angle onto the defined target location. This paper describes the optimisation of the line geometry with respect to the switch regions in TT20, the integration into the existing facilities and the potential refurbishment of existing magnets. The optics design is shown, and the requirements for the magnets, power converters and instrumentation hardware are discussed.

  15. Discrimination of Charged Particles in a Neutral Beam Line by Using a Solid Scintillation Detector

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Jong-Kwan; Ko, Jewou; Liu, Dong [Jeju National University, Jeju (Korea, Republic of)

    2017-01-15

    In the past several decades, many studies have been conducted to search for non-baryonic dark matter, such as weakly interactive massive particles (WIMPs). In the search for WIMPs, charged particles incident on the detector are background particles because WIMPs are neutral. Charged particles originate from various sources, such as cosmic rays and laboratory materials surrounding the main detector. Therefore, a veto that discriminates charged particles can improve the particle detection efficiency of the entire experiment for detecting WIMPs. Here, we investigate in the thickness range of 1 mm to 5 mm, the optimal thickness of a polystyrene scintillator as a charged particle veto detector. We found that 3-mm-thick polystyrene provides the best performance to veto charged particles and the charged-particle background in the search for the WIMP signal. Furthermore, we fabricated 3-mm-thick and 5-mm-thick polystyrene charged particle veto detectors that will be used in an underground laboratory in the search for WIMP dark matter. After exposing those detectors are the actual beam line, we compared the rate of charged particles measured using those detectors and the rate simulated through a Monte Carlo simulation.

  16. Replaceable Be and Al windows for x-ray beam lines

    International Nuclear Information System (INIS)

    Oversluizen, T.; Stefan, P.M.

    1987-01-01

    Construction details and results of on-going performance tests are presented for two ultra-high vacuum compatible, free-convection cooled window assemblies in which the window disk is easily replaceable. In the Be window assembly, an 0.25 mm thick Be disk, 38 mm in diameter is sealed into a stainless steel adapter flange using 0.5 mm diameter pure Al wire. The assembly is leak tight to better than 1 x 10 -10 atm cm 3 /sec before and after multiple bakeouts to 250 0 C. However, an unexplained temperature-dependent He leak, with a maximum magnitude in the low 10 -10 atm cm 3 /sec range at 250 0 C, appears during bakeout. Possible causes for this leak are discussed. In the Al window assembly, a 25 μm thick Al disc, 60 mm in diameter acts as the sealing medium as well as the window material over a 10 mm by 50 mm opening. This assembly remains leak tight to better than 1 x 10 -10 atm cm 3 /sec throughout multiple bakeouts to 150 0 C and has been successfully tested in white and monochromatic beam lines at the NSLS x-ray ring. 25 refs

  17. Replaceable Be and Al windows for X-ray beam lines

    International Nuclear Information System (INIS)

    Oversluizen, T.; Stefan, P.M.

    1988-01-01

    Construction details and results of on-going performance tests are presented for two ultrahigh vacuum compatible, free-convection cooled window assemblies in which the window disk is easily replaceable. In the Be window assembly, an 0.25 mm thick Be disk, 38 mm in diameter, is sealed into a stainless steel adapter flange using 0.5 mm diameter pure Al wire. The assembly is leak tight to better than 1x10 -10 atm cm 3 /s before and after multiple bakeouts to 250 0 C. However, an unexplained temperature-dependent He leak, with a maximum magnitude in the low 10 -10 atm cm 3 /s range at 250 0 C, appears during bakeout. Possible causes for this leak are discussed. In the Al window assembly, a 25 μm thick Al disc, 60 mm in diameter, acts as the sealing medium as well as the window material over a 10 mm x 50 mm opening. This assembly remains leak tight to better than 1x10 -10 atm cm 3 /s throughout multiple bakeouts to 150 0 C and has been successfully rested in white and monochromatic beam lines at the NSLS X-ray ring. (orig.)

  18. Particle-core model for transverse dynamics of beam halo

    Directory of Open Access Journals (Sweden)

    T. P. Wangler

    1998-12-01

    Full Text Available The transverse motion of beam halo particles is described by a particle-core model which uses the space-charge field of a continuous cylindrical oscillating beam core in a uniform linear focusing channel to provide the force that drives particles to large amplitudes. The model predicts a maximum amplitude for the resonantly-driven particles as a function of the initial mismatch. We have calculated these amplitude limits and have estimated the growth times for extended-halo formation as a function of both the space-charge tune-depression ratio and a mismatch parameter. We also present formulas for the scaling of the maximum amplitudes as a function of the beam parameters. The model results are compared with multiparticle simulations and we find very good agreement for a variety of initial particle distributions.

  19. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup −} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  20. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    International Nuclear Information System (INIS)

    Valerio-Lizarraga, Cristhian A.; Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard; Leon-Monzon, Ildefonso; Midttun, Øystein

    2014-01-01

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H − beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree

  1. Modeling and simulation of a proton beam space-charge neutralization

    International Nuclear Information System (INIS)

    Fleury, Xavier

    2000-01-01

    The aim of this work is to understand and to model the build-up of a plasma in the low-energy beam transport line of a proton accelerator. This plasma is generated by the beam, which ionizes the residual gas remaining in this low-energy section. By neutralizing the space-charge of the beam, the plasma modifies its transport, thus, to control the beam, it is necessary to study this phenomenon. In this work, we consider a continuous beam and we take interest in the stationary states of the plasma. We first restrict the description of the plasma to a plane perpendicular to the beam, by assuming that the beam and the plasma are longitudinally invariant. The build-up of the plasma is first described with a kinetic model where binary collisions are neglected, based on the Vlasov-Poisson system with source terms which take into account ionization. We prove mathematically that this system has no stationary solution, by using appropriate subsets of the phase-space that we call trapping-sets. Yet, measurements show that the plasma evolves towards a steady state. To account for this evolution, we modify the source terms of the model. The resulting model is solved by a particle-in-cell method, and the results are compared to the measurements. Then, we show that binary collisions between plasma electrons and beam ions or gas molecules help to maintain the equilibrium of the plasma. In the last part of the thesis, we use hydrodynamic models to investigate more easily the coupling between transversal and longitudinal effects. The preliminary study of a one-dimensional model enables to find the behaviour of the transverse potential of the plasma. Finally, a two-dimensional model of the transport of the beam when it is neutralized by the plasma is solved numerically, which shows that the longitudinal electric field should play an important role in the set-up of the equilibrium of the plasma. (author) [fr

  2. Simulation and modeling of the Gamble II self-pinched ion beam transport experiment

    International Nuclear Information System (INIS)

    Rose, D.V.; Ottinger, P.F.; Hinshelwood, D.D.

    1999-01-01

    Progress in numerical simulations and modeling of the self-pinched ion beam transport experiment at the Naval Research Laboratory (NRL) is reviewed. In the experiment, a 1.2-MeV, 100-kA proton beam enters a 1-m long, transport region filled with a low pressure gas (30--250 mTorr helium, or 1 Torr air). The time-dependent velocity distribution function of the injected ion beam is determined from an orbit code that uses a pinch-reflex ion diode model and the measured voltage and current from this diode on the Gamble II generator at NRL. This distribution function is used as the beam input condition for numerical simulations carried out using the hybrid particle-in-cell code IPROP. Results of the simulations will be described, and detailed comparisons will be made with various measurements, including line-integrated electron-density, proton-fluence, and beam radial-profile measurements. As observed in the experiment, the simulations show evidence of self-pinching for helium pressures between 35 and 80 mTorr. Simulations and measurements in 1 Torr air show ballistic transport. The relevance of these results to ion-driven inertial confinement fusion will be discussed

  3. Protocol of image guided off-line using cone beam CT megavoltage; Protocolo de imagen guiada off-line mediante Cone Beam CT de megavoltaje

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Ruiz-Zorrilla, J.; Fernandez Leton, J. P.; Perez Moreno, J. M.; Zucca Aparicio, D.; Minambres Moro, A.

    2013-07-01

    The goal of image guided protocols offline is to reduce systematic errors in positioning of the patient in the treatment unit, being more important than the random errors, since the systematic have one contribution in the margin of the CTV to the PTV. This paper proposes a protocol for image guided offline with the different actions to take with their threshold values evaluated previously by anatomic location in a sample of 474 patients and 4821Cone beam Megavoltaje CT (CBCT). (Author)

  4. A simple model of hose instabilities in rotating electron beams

    International Nuclear Information System (INIS)

    Brandenburg, J.E.

    1983-01-01

    A simple foilless diode with a properly designed transmission line feed can generate an intense, wellcollimated annular electron beam. As part of the AID project at Los Alamos, a 3-MeV annular beam is routinely generated with a radius of 1 cm, a thickness of about 100 μ, a current density of about 1 MA/cm 2 , and a scattering angle of about 30 mrad. The particle-in-cell code CEMIT has been used previously to investigate the properties of foilless diodes. It is found that the beam quality can vary significantly during this transition. The best quality beam is achieved by a configuration that is not foilless or foil, but a combination. Microwave generation within the diode and zero-frequency cyclotron wave growth appear to be the major source of energy spread and angular scatter on the beam. Changes in the cathode shape that do not alter the current density profile greatly can change change the energy spread significantly due to microwave generation. Simulations have typically been carried out using a short rise time on the voltage pulse and then holding the voltage constant to obtain a steady state result. When driven by a real source, however, the voltage is continually changing on a time scale that is slow compared with the transit time of the speed of light across the diode. Simulations in which the voltage changes continually have been carried out for both inner and outer conductor foilless diodes. It is found that energy spread dominates the beam at low voltage while angular scatter dominates at higher voltage. Based upon these simulations, a more complete time history of this class of diode is possible

  5. Modeling operational behavior of a disassembly line

    Science.gov (United States)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2004-12-01

    In this paper we present a dynamic kanban (pull) system specifically developed for disassembly lines. This type of kanban system is much more complex than the traditional kanban system used in assembly lines. For instance, unlike the assembly line where the external demand occurs only at the last station, the demands in the disassembly case also occur at any of the intermittent stations. The reason is that as a product moves on the disassembly line, various parts are disassembled at every station and accumulated at that station. Therefore, there are as many demand sources as there are number of parts. We consider a case example involving the end-of-life products. Based on the precedence relationships and other criteria such as hazardous properties of the parts, we balance the disassembly line. The results of the disassembly line-balancing problem (DLBP) are used as input to the proposed dynamic kanban system for disassembly line (DKSDL). We compare the performance of the DKSDL to the modified kanban system for disassembly line (MKSDL), which was previously introduced by the authors. We show, via simulation, that the DKSDL is far superior to MKSDL considered.

  6. Properties of 3-dimensional line location models

    DEFF Research Database (Denmark)

    Brimberg, Jack; Juel, Henrik; Schöbel, Anita

    2002-01-01

    We consider the problem of locating a line with respect to some existing facilities in 3-dimensional space, such that the sum of weighted distances between the line and the facilities is minimized. Measuring distance using the l\\_p norm is discussed, along with the special cases of Euclidean...

  7. X-ray diffraction using synchrotron radiation on the G.I.L.D.A. beam line at the E.S.R.F

    Energy Technology Data Exchange (ETDEWEB)

    Balerna, A. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Meneghini, C. [INFN, Laboratori Nazionali di Frascati, Rome (Italy)]|[INFM, Genoa (Italy); Bordoni, S. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica; Mobilio, S. [Rome Univ. III (Italy). Dip. di Fisica `E. Amaldi`

    1996-09-01

    The aim of this lecture is to make a short introduction on Synchrotron radiation, its history and main properties. The main components of a synchrotron radiation beam line will be described. The Italian beam line, General purpose Italian beam line Line for Diffraction and Absorption (G.I.L.D.A.) at the European Synchrotron Radiation Facility (E.S.R.F.) in Grenoble will be used as an example. The G.I.L.D.A. diffractometer will be described in detail reporting also some experimental results.

  8. X-ray diffraction using synchrotron radiation on the G.I.L.D.A. beam line at the E.S.R.F

    International Nuclear Information System (INIS)

    Balerna, A.; Bordoni, S.; Mobilio, S.

    1996-01-01

    The aim of this lecture is to make a short introduction on Synchrotron radiation, its history and main properties. The main components of a synchrotron radiation beam line will be described. The Italian beam line, General purpose Italian beam line Line for Diffraction and Absorption (G.I.L.D.A.) at the European Synchrotron Radiation Facility (E.S.R.F.) in Grenoble will be used as an example. The G.I.L.D.A. diffractometer will be described in detail reporting also some experimental results

  9. Modelling and simulation of beam formation in electron guns

    International Nuclear Information System (INIS)

    Sabchevski, S.; Barbarich, I.

    1996-01-01

    This paper describes a new PC version of the software package GUN-EBT for computer simulation of beam formation in rotationally symmetric electron guns with thermionic cathodes. It is based on a self-consistent physical model which takes into account the beam space charge and the initial velocity effects. The theoretical framework used for both the formulation of the model and for the interpretation of the results of numerical experiments is the formalism of the charged particle dynamics in phase space. This enables not only a trajectory analysis (ray tracing) but also a phase-space analysis of beams to be performed. The package can be used as an effective tool for computer aided design and optimization of electron guns in various electron-optical systems. The operation of the package is illustrated with a typical example. (orig.)

  10. Modelling and simulation of beam formation in electron guns

    Energy Technology Data Exchange (ETDEWEB)

    Sabchevski, S. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. po Elektronika; Mladenov, G. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. po Elektronika; Titov, A. [St. Petersburg State Electrotechnical University, St. Petersburg (Russian Federation); Barbarich, I. [St. Petersburg State Electrotechnical University, St. Petersburg (Russian Federation)

    1996-11-01

    This paper describes a new PC version of the software package GUN-EBT for computer simulation of beam formation in rotationally symmetric electron guns with thermionic cathodes. It is based on a self-consistent physical model which takes into account the beam space charge and the initial velocity effects. The theoretical framework used for both the formulation of the model and for the interpretation of the results of numerical experiments is the formalism of the charged particle dynamics in phase space. This enables not only a trajectory analysis (ray tracing) but also a phase-space analysis of beams to be performed. The package can be used as an effective tool for computer aided design and optimization of electron guns in various electron-optical systems. The operation of the package is illustrated with a typical example. (orig.).

  11. Head-On Beam-Beam Interactions in High-Energy Hadron Colliders. GPU-Powered Modelling of Nonlinear Effects

    CERN Document Server

    AUTHOR|(CDS)2160109; Støvneng, Jon Andreas

    2017-08-15

    The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strength of the beam-beam interactions will be higher after the upgrade to the High-Luminosity Large Hadron Collider, and also in the next generation of machines, as the Future Circular Hadron Collider. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and drives resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. For this thesis, a new code named CABIN (Cuda-Accelerated Beam-beam Interaction) has been developed to study the limitations caused by the impact of strong beam-beam interactions. In particular, the evolution of the beam emittance and beam intensity has been monitored to study the impact quantitatively...

  12. Simple Numerical Model of Laminated Glass Beams

    Directory of Open Access Journals (Sweden)

    A. Zemanová

    2008-01-01

    Full Text Available This paper presents a simple Finite Element model aimed at efficient simulation of layered glass units. The approach is based on considering the independent kinematics of each layer, tied together via Lagrange multipliers. Validation and verification of the resulting model against independent data demonstrate its accuracy, showing its potential for generalization towards more complex problems. 

  13. Modeling beam-front dynamics at low gas pressures

    International Nuclear Information System (INIS)

    Briggs, R.J.; Yu, S.

    1982-01-01

    The dynamics of space charge neutralization at the front of an intense self-focused electron beam pulse exhibits important differences in different gas pressure regimes. At very low pressures, the beam front is in the so-called ion-focused regime (IFR) where all secondary electrons are expelled from the beam region by the radial electric field without causing significant additional ionization. We estimate the upper pressure boundary of this regime by considering the distance scale length for cascade (avalanche) ionization. Data from the FX-25 diode experiments indicate a critical transition pressure (P/sub c/) that agrees with this estimate and with its scaling among various gas types. Normal mobility-limited treatments (local conductivity models) of the secondary electrons at the beam front are not justified until the gas pressure is 10 to 50 times higher than P/sub c/, due to runaway of these secondary electrons in the strong space-charge electric field at the lower pressures. The main conclusion of this study is that a non-local phase space (Boltzmann) treatment of the secondary electrons is required to accurately describe these different beam front regimes and the transitions between them; such a code model is currently under development

  14. Alpha particle diagnostic beam line system to generate an intense Li0 beam with an ORNL SITEX source

    International Nuclear Information System (INIS)

    Dagenhart, W.K.; Stirling, W.L.; Tsai, C.C.; Whealton, J.H.

    1985-01-01

    The Oak Ridge National Laboratory (ORNL) SITEX (Surface Ionization with Transverse Extraction) negative ion source utilizes a 100-V/20-A reflex arc discharge in a 1300-gauss magnetic field to generate Cs+ ions and H+ or D+ ions, depending on the beam required. A shaped molybdenum plate is placed directly behind the arc column. Cesium coverage on this plate is used to minimize the surface work function, which requires two-thirds of a monolayer coverage. Cesium coverage ia adjusted both by cesium flow control into the arc discharge chamber and by temperature control of the converter using gaseous-helium cooling channels in the converter plate. Normal converter operational temperatures are 300 0 to 500 0 C H - /D - beams are generated at the biased converter surface (-150 V with respect to the anode) by Cs + sputtering of absorbed hydrogen or deuterium and by the reflection-conversion mechanism of H + /D + ions which strike the converter surface at 150 eV. The negative ions are accelerated through the 150-V plasma sheath at the converter surface and are focused by the converter geometry and magnetic field so as to pass through the exit aperture with minimum angular divergence. The ion optics of the SITEX accelerator has been calculated using the ORNL 3-D optics code and results in a divergence perpendicular to the slot of theta/sub perpendicular rms/ = 0.35 0 and parallel to the slot of theta/sub parallel rms/ = 0.18 0 . This beam divergence should be adequate for injection into a radio frequency quadrupole (RFQ) for further acceleration

  15. Experimental results of Tore Supra neutral beam injector in the line testing system

    International Nuclear Information System (INIS)

    Fumelli, M.; Jequier, F.

    1991-04-01

    Results of the tests carried out on one of the six Tore Supra neutral beam injectors are reported. Several minor modifications of the injector design allowed us to operate up to 92 keV - 30 A beams limited by the high voltage power supplies. Results of studies on different topics like new titanium pumping system, neutron yield from neutraliser and target, beam conditioning and breakdown statistical analysis are also reported [fr

  16. Design of the prototype of a beam transport line for handling and selection of low energy laser-driven beams

    Czech Academy of Sciences Publication Activity Database

    Schillaci, F.; Maggiore, M.; Cirrone, G.A.P.; Cuttone, G.; Pisciotta, P.; Costa, M.; Rifuggiato, D.; Romano, F.; Scuderi, Valentina

    2016-01-01

    Roč. 837, Nov (2016), s. 80-87 ISSN 0168-9002 R&D Projects: GA MŠk EF15_008/0000162; GA MŠk LQ1606; GA MŠk LM2015065 Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162 Institutional support: RVO:68378271 Keywords : particle acceleration * quadrupoles * dipoles * magnetic lens * beam dynamics Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 1.362, year: 2016

  17. Simulation and beam line experiments for the superconducting ECRion source VENUS

    Energy Technology Data Exchange (ETDEWEB)

    Todd, Damon S.; Leitner, Daniela; Grote, David P.; Lyneis, ClaudeM.

    2007-09-10

    The particle-in-cell code Warp has been enhanced toincorporate both two- and three-dimensional sheath extraction modelsgiving Warp the capability of simulating entire ion beam transportsystems including the extraction of beams from plasma sources. In thisarticle we describe a method of producing initial ion distributions forplasma extraction simulations in electron cyclotron resonance (ECR) ionsources based on experimentally measured sputtering on the source biaseddisc. Using this initialization method, we present preliminary resultsfor extraction and transport simulations of an oxygen beam and comparethem with experimental beam imaging on a quartz viewing plate for thesuperconducting ECR ion source VENUS.

  18. On-line cone beam CT image guidance for vocal cord tumor targeting

    International Nuclear Information System (INIS)

    Osman, Sarah O.S.; Boer, Hans C.J. de; Astreinidou, Eleftheria; Gangsaas, Anne; Heijmen, Ben J.M.; Levendag, Peter C.

    2009-01-01

    Background and purpose: We are developing a technique for highly focused vocal cord irradiation in early glottic carcinoma to optimally treat a target volume confined to a single cord. This technique, in contrast with the conventional methods, aims at sparing the healthy vocal cord. As such a technique requires sub-mm daily targeting accuracy to be effective, we investigate the accuracy achievable with on-line kV-cone beam CT (CBCT) corrections. Materials and methods: CBCT scans were obtained in 10 early glottic cancer patients in each treatment fraction. The grey value registration available in X-ray volume imaging (XVI) software (Elekta, Synergy) was applied to a volume of interest encompassing the thyroid cartilage. After application of the thus derived corrections, residue displacements with respect to the planning CT scan were measured at clearly identifiable relevant landmarks. The intra- and inter-observer variations were also measured. Results: While before correction the systematic displacements of the vocal cords were as large as 2.4 ± 3.3 mm (cranial-caudal population mean ± SD Σ), daily CBCT registration and correction reduced these values to less than 0.2 ± 0.5 mm in all directions. Random positioning errors (SD σ) were reduced to less than 1 mm. Correcting only for translations and not for rotations did not appreciably affect this accuracy. The residue random displacements partly stem from intra-observer variations (SD = 0.2-0.6 mm). Conclusion: The use of CBCT for daily image guidance in combination with standard mask fixation reduced systematic and random set-up errors of the vocal cords to <1 mm prior to the delivery of each fraction dose. Thus, this facilitates the high targeting precision required for a single vocal cord irradiation.

  19. Atomistic modeling of ion beam induced amorphization in silicon

    International Nuclear Information System (INIS)

    Pelaz, Lourdes; Marques, Luis A.; Lopez, Pedro; Santos, Ivan; Aboy, Maria; Barbolla, Juan

    2005-01-01

    Ion beam induced amorphization in Si has attracted significant interest since the beginning of the use of ion implantation for the fabrication of Si devices. Nowadays, a renewed interest in the modeling of amorphization mechanisms at atomic level has arisen due to the use of preamorphizing implants and high dopant implantation doses for the fabrication of nanometric-scale Si devices. In this work, we briefly describe the existing phenomenological and defect-based amorphization models. We focus on the atomistic model we have developed to describe ion beam induced amorphization in Si. In our model, the building block for the amorphous phase is the bond defect or IV pair, whose stability increases with the number of surrounding IV pairs. This feature explains the regrowth behavior of different damage topologies and the kinetics of the crystalline to amorphous transition. The model provides excellent quantitative agreement with experimental results

  20. Shear beams in finite element modelling : Software implementation and validation

    NARCIS (Netherlands)

    Schreppers, G.J.; Hendriks, M.A.N.; Boer, A.; Ferreira, D.; Kikstra, W.P.

    2015-01-01

    Fiber models for beam and shell elements allow for relatively rapid finite element analysis of concrete structures and structural elements. This project aims at the development of the formulation of such elements and a pilot implementation. The reduction of calculation time and degrees of freedom

  1. Design study of beam transport lines for BioLEIR facility at CERN

    Science.gov (United States)

    Ghithan, S.; Roy, G.; Schuh, S.

    2017-09-01

    The biomedical community has asked CERN to investigate the possibility to transform the Low Energy Ion Ring (LEIR) accelerator into a multidisciplinary, biomedical research facility (BioLEIR) that could provide ample, high-quality beams of a range of light ions suitable for clinically oriented, fundamental research on cell cultures and for radiation instrumentation development. The present LEIR machine uses fast beam extraction to the next accelerator in the chain, eventually leading to the Large Hadron Collider (LHC) . To provide beam for a biomedical research facility, a new slow extraction system must be installed. Two horizontal and one vertical experimental beamlines were designed for transporting the extracted beam to three experimental end-stations. The vertical beamline (pencil beam) was designed for a maximum energy of 75 MeV/u for low-energy radiobiological research, while the two horizontal beamlines could deliver up to 440 MeV/u. One horizontal beamline shall be used preferentially for biomedical experiments and shall provide pencil beam and a homogeneous broad beam, covering an area of 5 × 5 cm2 with a beam homogeneity of ±5%. The second horizontal beamline will have pencil beam only and is intended for hardware developments in the fields of (micro-)dosimetry and detector development. The minimum full aperture of the beamlines is approximately 100 mm at all magnetic elements, to accommodate the expected beam envelopes. Seven dipoles and twenty quadrupoles are needed for a total of 65 m of beamlines to provide the specified beams. In this paper we present the optical design for the three beamlines.

  2. Dynamical model for the narrow line region of Seyfert galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Mobasher, B.; Raine, D.J.

    1987-09-01

    Detailed emission line ratios and profiles have been computed for the 'catapult' model of the NLR. According to this model the emission lines arise from interstellar clouds interacting with a wind from the central source. For clouds which are ejected by the ram pressure of the wind agreement is found with average Seyfert 2 line ratios for the main diagnostic lines, within the 2sigma dispersions. This also gives the observed constancy of line profiles for different lines. The Seyfert 1 line ratios are obtained by adding a component of clouds which are not ejected. The predicted line ratios (relative to (O III)lambda5007) for Seyfert 1s agree to better than 1sigma with the observed averages.

  3. Modeling transmission and scatter for photon beam attenuators.

    Science.gov (United States)

    Ahnesjö, A; Weber, L; Nilsson, P

    1995-11-01

    The development of treatment planning methods in radiation therapy requires dose calculation methods that are both accurate and general enough to provide a dose per unit monitor setting for a broad variety of fields and beam modifiers. The purpose of this work was to develop models for calculation of scatter and transmission for photon beam attenuators such as compensating filters, wedges, and block trays. The attenuation of the beam is calculated using a spectrum of the beam, and a correction factor based on attenuation measurements. Small angle coherent scatter and electron binding effects on scattering cross sections are considered by use of a correction factor. Quality changes in beam penetrability and energy fluence to dose conversion are modeled by use of the calculated primary beam spectrum after passage through the attenuator. The beam spectra are derived by the depth dose effective method, i.e., by minimizing the difference between measured and calculated depth dose distributions, where the calculated distributions are derived by superposing data from a database for monoenergetic photons. The attenuator scatter is integrated over the area viewed from the calculation point of view using first scatter theory. Calculations are simplified by replacing the energy and angular-dependent cross-section formulas with the forward scatter constant r2(0) and a set of parametrized correction functions. The set of corrections include functions for the Compton energy loss, scatter attenuation, and secondary bremsstrahlung production. The effect of charged particle contamination is bypassed by avoiding use of dmax for absolute dose calibrations. The results of the model are compared with scatter measurements in air for copper and lead filters and with dose to a water phantom for lead filters for 4 and 18 MV. For attenuated beams, downstream of the buildup region, the calculated results agree with measurements on the 1.5% level. The accuracy was slightly less in situations

  4. Space charge templates for high-current beam modeling

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiev, Leonid G.; /Fermilab

    2008-07-01

    A computational method to evaluate space charge potential and gradients of charged particle beam in the presence of conducting boundaries, has been introduced. The three-dimensional (3D) field of the beam can be derived as a convolution of macro Green's functions (template fields), satisfying the same boundary conditions, as the original beam. Numerical experiments gave a confidence that space charge effects can be modeled by templates with enough accuracy and generality within dramatically faster computational times than standard combination: a grid density + Poisson solvers, realized in the most of Particle in Cell codes. The achieved rapidity may significantly broaden the high-current beam design space, making the optimization in automatic mode possible, which so far was only feasible for simplest self-field formulations such as rms envelope equations. The template technique may be used as a standalone program, or as an optional field solver in existing beam dynamics codes both in one-passage structures and in rings.

  5. On-line and precise measurement of iron wear using thin layer activation reactions by proton beam

    International Nuclear Information System (INIS)

    Kosako, Toshiso; Nishimura, Kazuo.

    1990-01-01

    For the purpose of the on-line measurement of iron wear, thin layer activation (TLA) method or surface layer activation (SLA) method has been carried out since early 1970s. This method uses the irradiation of charged particle beam like protons from an accelerator onto a metal surface to produce a thin activated layer of several tens μm. The wear of this activated layer is measured by nondestructive on-line method with a radiation detector. There are two methods of the measurement. One is the activity loss measurement on the surface, and the other is the activity measurement of the metal debris collected in a filter. The former method is considered here. The purpose it to measure the wear of engine cam noses to help the development of good engine oil. Proton beam irradiation with a tandem van de Graaff accelerator, wear calibration using a gamma ray spectrometer, on-line wear measurement of cam noses of car engines by TLA method and so on are reported. The 7.00 MeV proton beam from a van de Graaff accelerator was used for activation, and Co-56, Co-57 and Co-58 were obtained in thin layers. (K.I.)

  6. Model and observations of Schottky-noise suppression in a cold heavy-ion beam.

    Science.gov (United States)

    Danared, H; Källberg, A; Rensfelt, K-G; Simonsson, A

    2002-04-29

    Some years ago it was found at GSI in Darmstadt that the momentum spread of electron-cooled beams of highly charged ions dropped abruptly to very low values when the particle number decreased to 10 000 or less. This has been interpreted as an ordering of the ions, such that they line up after one another in the ring. We report observations of similar transitions at CRYRING, including an accompanying drop in Schottky-noise power. We also introduce a model of the ordered beam from which the Schottky-noise power can be calculated numerically. The good agreement between the model calculation and the experimental data is seen as evidence for a spatial ordering of the ions.

  7. HAWC2 and BeamDyn: Comparison Between Beam Structural Models for Aero-Servo-Elastic Frameworks: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pavese, Christian; Kim, Taeseong; Wang, Qi; Jonkman, Jason; Sprague, Michael A.

    2016-08-01

    This work presents a comparison of two beam codes for aero-servo-elastic frameworks: a new structural model for the aeroelastic code HAWC2 and a new nonlinear beam model, BeamDyn, for the aeroelastic modularization framework FAST v8. The main goal is to establish the suitability of the two approaches to model the structural behaviour of modern wind turbine blades in operation. Through a series of benchmarking structural cases of increasing complexity, the capability of the two codes to simulate highly nonlinear effects is investigated and analyzed. Results show that even though the geometrically exact beam theory can better model effects such as very large deflections, rotations, and structural couplings, an approach based on a multi-body formulation assembled through linear elements is capable of computing accurate solutions for typical nonlinear beam theory benchmarking cases.

  8. Tornado risk model for transmission line design

    CSIR Research Space (South Africa)

    Milford, RV

    1997-11-01

    Full Text Available is in combination with ice loading. The wind load used in most codes of practice and design recommendations for transmission line design have until recently been based almost exclusively on large-scale wind storms, which may include severe storms such as hurricanes...

  9. Multiobjective Fuzzy Mixed Assembly Line Sequencing Optimization Model

    Directory of Open Access Journals (Sweden)

    Farzad Tahriri

    2014-01-01

    Full Text Available It can be deduced from previous studies that there exists a research gap in assembly line sequencing optimization model for mixed-model production lines. In particular, there is a lack of studies which focus on the integration between job shop and assembly lines using fuzzy techniques. Hence, this paper is aimed at addressing the multiobjective mixed-model assembly line sequencing problem by integrating job shop and assembly production lines for factories with modular layouts. The primary goal is to minimize the make-span, setup time, and cost simultaneously in mixed-model assembly lines. Such conflicting goals arise when switching between different products. A genetic algorithm (GA approach is used to solve this problem, in which trapezoidal fuzzy numbers are implemented for variables such as operation and travelling time in order to generate results with higher accuracy and representative of real-case data.

  10. Iron K Lines from Accretion Disks: Models for Line Production and Spectroscopic Constraints

    Science.gov (United States)

    Kallman, Timothy; Palmeri, Patrick

    2004-01-01

    Measured profiles of the iron K lines provide important dynamical information about emitting matrial in compact objects. However, much of the modeling work which has been used to infer the location and origin of line observed from AGN and galactic black hole sources is based on highly simplified assumptions about the microphysics of K line emission. In particular, many of the intrinsic line energies, widths and emissivities are based on central-field atomic calculations. We present the results of new calculations of the quantities for the entire iron isonuclear sequence, and demonstrate that the intrinsic K line spectra contain considerably more complexity than has been previously considered. We also present calculations of iron K emission and absorption spectra which include the new data, including the local spectrum radiated from an X-ray illuminated accretion disk. The implications for the interpretation of observed iron K lines from black hole sources will be discussed.

  11. An energy-based beam hardening model in tomography

    Energy Technology Data Exchange (ETDEWEB)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E [Vision Lab, Physics Departement, University of Antwerp (RUCA) (Belgium)

    2002-12-07

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography ({mu}CT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages.

  12. An energy-based beam hardening model in tomography

    International Nuclear Information System (INIS)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E

    2002-01-01

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography (μCT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages

  13. Computer generation of cobalt-60 single beam dose distribution using an analytical beam model

    International Nuclear Information System (INIS)

    Jayaraman, S.

    1981-01-01

    A beam dose calculation model based on evaluation of tissue air ratios (TAR) and scatter air ratios (SAR) for cobalt-60 beams of rectangular cross section has been developed. Off-central axis fall-off of primary radiation intensity is derived by an empirical formulation involving an arctangent function with the slope of the geometrical penumbra acting as an essential constant. Central axis TAR and SAR values are assessed by semi-empirical polynomial expressions employing the two sides of the rectangular field as the bariables. The model utilises a minimum number of parametric constants and is useful for computer generation of isodose curves. The model is capable of accounting for situations where wedge filters or split field shielding blocks, are encountered. Further it could be widely applied with minor modifications to several makes of the currently available cobalt-60 units. The paper explains the model and shows examples of the results obtained in comparison with the corresponding experimentally determined dose distributions. (orig.) [de

  14. Design of Air-Cooled Beam Dump for Extraction Line of PS Booster

    CERN Document Server

    Perillo-Marcone, A; Venturi, V; Antonakakis, T; Vlachoudis, V; Nowak, E; Mason, G; Battistin, M; Czapski, M; Sgobba, S

    2013-01-01

    A new beam dump has been designed, which withstands the future proton beam extracted from the Proton Syncrotron Booster (PSB) at CERN, consisting of up to 1E14 protons per pulse at 2 GeV after its upgrade in 2018/2019. In order to be able to efficiently release the deposited heat, the new dump will be made out of a single cylindrical block of a copper alloy and cooled by forced ventilation. In order to determine the energy density distribution deposited by the beam in the dump, Monte Carlo simulations were performed using FLUKA, and thermomechanical analyses carried out by importing the energy density into Ansys. In addition, CFD simulations of the airflow were carried out in order to accurately estimate the heat transfer convection coefficient on the surface of the dump. This paper describes the design process and highlights the constraints of integrating a new dump for increased beam power into the existing facility.

  15. Test bed for a long pulse 160 KeV neutral beam-line

    International Nuclear Information System (INIS)

    Becherer, R.; Bariaud, A.; Bottiglioni, F.; Bussac, J.P.; Desmons, M.; Fumelli, M.; Raimbault, P.; Sledziewski, Z.; Valckx, F.P.G.

    1983-01-01

    The development of 160 KeV neutral injectors with deuterium beams is required for JET - operation. A test bed has been constructed, allowing the operation and testing of quasi DC-neutral beams (10 sec) of 60 A in the energy range of 80 to 160 KeV. For deuterium operation the whole test bed will be moved into a concrete blockhouse for radiation protection. Different elements are described. (author)

  16. Gas Transport and Density Control in the HYLIFE Heavy-Ion Beam Lines

    International Nuclear Information System (INIS)

    Debonnel, Christophe S.; Welch, Dale R.; Rose, David V.; Lawrence, Simon S.Yu; Peterson, Per F.

    2003-01-01

    The effective propagation and focusing of heavy-ion beams in the final-focus magnet region of inertial fusion target chambers require controlling the background gas density and pressure in the beam tubes. Liquid vortexes will coat the inside of the tubes next to the beam ports and will help eliminate the need for mechanical shutters to mitigate the venting of target chamber background gas into the final-focus magnet region. Before the neutralizing region, the beam space charge is high, and ablation and target debris deposition in the final-focus magnet region may cause voltage breakdown. Previous studies focused on evaluating the amount of target chamber debris reaching the entrance of the beam ports. The TSUNAMI code has now been used to assess the density, temperature, and velocity of the vortex debris transported ∼3 m up the beam tubes and reaching the final-focus magnet region, assuming that the liquid vortexes are perfectly absorbing surfaces. To further mitigate debris deposition in the final-focus magnet region, and prevent voltage breakdown, a 'magnetic shutter' has been envisaged to divert the debris out of the final-focus region. This shutter will prevent the hot ablation debris from reaching the magnet region and, coupled to some ionizing scheme, will conveniently suppress early ingression of debris into the final-focus magnet region

  17. A model to determine the initial phase space of a clinical electron beam from measured beam data.

    NARCIS (Netherlands)

    Janssen, J.J.M.; Korevaar, E.W.; Battum, L.J. van; Storchi, P.R.; Huizenga, H.

    2001-01-01

    Advanced electron beam dose calculation models for radiation oncology require as input an initial phase space (IPS) that describes a clinical electron beam. The IPS is a distribution in position, energy and direction of electrons and photons in a plane in front of the patient. A method is presented

  18. Modeling skin collimation using the electron pencil beam redefinition algorithm.

    Science.gov (United States)

    Chi, Pai-Chun M; Hogstrom, Kenneth R; Starkschall, George; Antolak, John A; Boyd, Robert A

    2005-11-01

    Skin collimation is an important tool for electron beam therapy that is used to minimize the penumbra when treating near critical structures, at extended treatment distances, with bolus, or using arc therapy. It is usually made of lead or lead alloy material that conforms to and is placed on patient surface. Presently, commercially available treatment-planning systems lack the ability to model skin collimation and to accurately calculate dose in its presence. The purpose of the present work was to evaluate the use of the pencil beam redefinition algorithm (PBRA) in calculating dose in the presence of skin collimation. Skin collimation was incorporated into the PBRA by terminating the transport of electrons once they enter the skin collimator. Both fixed- and arced-beam dose calculations for arced-beam geometries were evaluated by comparing them with measured dose distributions for 10- and 15-MeV beams. Fixed-beam dose distributions were measured in water at 88-cm source-to-surface distance with an air gap of 32 cm. The 6 x 20-cm2 field (dimensions projected to isocenter) had a 10-mm thick lead collimator placed on the surface of the water with its edge 5 cm inside the field's edge located at +10 cm. Arced-beam dose distributions were measured in a 13.5-cm radius polystyrene circular phantom. The beam was arced 90 degrees (-45 degrees to +45 degrees), and 10-mm thick lead collimation was placed at +/- 30 degrees. For the fixed beam at 10 MeV, the PBRA- calculated dose agreed with measured dose to within 2.0-mm distance to agreement (DTA) in the regions of high-dose gradient and 2.0% in regions of low dose gradient. At 15 MeV, the PBRA agreed to within a 2.0-mm DTA in the regions of high-dose gradient; however, the PBRA underestimated the dose by as much as 5.3% over small regions at depths less than 2 cm because it did not model electrons scattered from the edge of the skin collimation. For arced beams at 10 MeV, the agreement was 1-mm DTA in the high-dose gradient

  19. Spherical aberration correction with an in-lens N-fold symmetric line currents model.

    Science.gov (United States)

    Hoque, Shahedul; Ito, Hiroyuki; Nishi, Ryuji

    2018-04-01

    In our previous works, we have proposed N-SYLC (N-fold symmetric line currents) models for aberration correction. In this paper, we propose "in-lens N-SYLC" model, where N-SYLC overlaps rotationally symmetric lens. Such overlap is possible because N-SYLC is free of magnetic materials. We analytically prove that, if certain parameters of the model are optimized, an in-lens 3-SYLC (N = 3) doublet can correct 3rd order spherical aberration. By computer simulation, we show that the required excitation current for correction is less than 0.25 AT for beam energy 5 keV, and the beam size after correction is smaller than 1 nm at the corrector image plane for initial slope less than 4 mrad. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. LINES

    Directory of Open Access Journals (Sweden)

    Minas Bakalchev

    2015-10-01

    Full Text Available The perception of elements in a system often creates their interdependence, interconditionality, and suppression. The lines from a basic geometrical element have become the model of a reductive world based on isolation according to certain criteria such as function, structure, and social organization. Their traces are experienced in the contemporary world as fragments or ruins of a system of domination of an assumed hierarchical unity. How can one release oneself from such dependence or determinism? How can the lines become less “systematic” and forms more autonomous, and less reductive? How is a form released from modernistic determinism on the new controversial ground? How can these elements or forms of representation become forms of action in the present complex world? In this paper, the meaning of lines through the ideas of Le Corbusier, Leonidov, Picasso, and Hitchcock is presented. Spatial research was made through a series of examples arising from the projects of the architectural studio “Residential Transformations”, which was a backbone for mapping the possibilities ranging from playfulness to exactness, as tactics of transformation in the different contexts of the contemporary world.

  1. A multi-component evaporation model for beam melting processes

    Science.gov (United States)

    Klassen, Alexander; Forster, Vera E.; Körner, Carolin

    2017-02-01

    In additive manufacturing using laser or electron beam melting technologies, evaporation losses and changes in chemical composition are known issues when processing alloys with volatile elements. In this paper, a recently described numerical model based on a two-dimensional free surface lattice Boltzmann method is further developed to incorporate the effects of multi-component evaporation. The model takes into account the local melt pool composition during heating and fusion of metal powder. For validation, the titanium alloy Ti-6Al-4V is melted by selective electron beam melting and analysed using mass loss measurements and high-resolution microprobe imaging. Numerically determined evaporation losses and spatial distributions of aluminium compare well with experimental data. Predictions of the melt pool formation in bulk samples provide insight into the competition between the loss of volatile alloying elements from the irradiated surface and their advective redistribution within the molten region.

  2. Efficient Beam-Type Structural Modeling of Rotor Blades

    OpenAIRE

    Couturier, Philippe; Krenk, Steen

    2015-01-01

    The present paper presents two recently developed numerical formulations which enable accurate representation of the static and dynamic behaviour of wind turbine rotor blades using little modeling and computational effort. The first development consists of an intuitive method to extract fully coupled six by six cross-section stiffness matrices with limited meshing effort. Secondly, an equilibrium based beam element accepting directly the stiffness matrices and accounting for large variations ...

  3. Use of mathematical modelling in electron beam processing: A guidebook

    International Nuclear Information System (INIS)

    2010-01-01

    The use of electron beam irradiation for industrial applications, like the sterilization of medical devices or cross-linking of polymers, has a long and successful track record and has proven itself to be a key technology. Emerging fields, including environmental applications of ionizing radiation, the sterilization of complex medical and pharmaceutical products or advanced material treatment, require the design and control of even more complex irradiators and irradiation processes. Mathematical models can aid the design process, for example by calculating absorbed dose distributions in a product, long before any prototype is built. They support process qualification through impact assessment of process variable uncertainties, and can be an indispensable teaching tool for technologists in training in the use of radiation processing. The IAEA, through various mechanisms, including its technical cooperation programme, coordinated research projects, technical meetings, guidelines and training materials, is promoting the use of radiation technologies to minimize the effects of harmful contaminants and develop value added products originating from low cost natural and human made raw materials. The need to publish a guidebook on the use of mathematical modelling for design processes in the electron beam treatment of materials was identified through the increased interest of radiation processing laboratories in Member States and as a result of recommendations from several IAEA expert meetings. In response, the IAEA has prepared this report using the services of an expert in the field. This publication should serve as both a guidebook and introductory tutorial for the use of mathematical modelling (using mostly Monte Carlo methods) in electron beam processing. The emphasis of this guide is on industrial irradiation methodologies with a strong reference to existing literature and applicable standards. Its target audience is readers who have a basic understanding of electron

  4. Optimizing the modified microdosimetric kinetic model input parameters for proton and 4He ion beam therapy application

    Science.gov (United States)

    Mairani, A.; Magro, G.; Tessonnier, T.; Böhlen, T. T.; Molinelli, S.; Ferrari, A.; Parodi, K.; Debus, J.; Haberer, T.

    2017-06-01

    Models able to predict relative biological effectiveness (RBE) values are necessary for an accurate determination of the biological effect with proton and 4He ion beams. This is particularly important when including RBE calculations in treatment planning studies comparing biologically optimized proton and 4He ion beam plans. In this work, we have tailored the predictions of the modified microdosimetric kinetic model (MKM), which is clinically applied for carbon ion beam therapy in Japan, to reproduce RBE with proton and 4He ion beams. We have tuned the input parameters of the MKM, i.e. the domain and nucleus radii, reproducing an experimental database of initial RBE data for proton and He ion beams. The modified MKM, with the best fit parameters obtained, has been used to reproduce in vitro cell survival data in clinically-relevant scenarios. A satisfactory agreement has been found for the studied cell lines, A549 and RENCA, with the mean absolute survival variation between the data and predictions within 2% and 5% for proton and 4He ion beams, respectively. Moreover, a sensitivity study has been performed varying the domain and nucleus radii and the quadratic parameter of the photon response curve. The promising agreement found in this work for the studied clinical-like scenarios supports the usage of the modified MKM for treatment planning studies in proton and 4He ion beam therapy.

  5. Modeling of antihydrogen beam formation for interferometric gravity measurements

    Science.gov (United States)

    Gerber, Sebastian

    2018-02-01

    In this paper a detailed computational study is performed on the formation of antihydrogen via three-body-recombination of positrons and antiprotons in a Penning trap with a specific focus on formation of a beam of antihydrogen. First, an analytical model is presented to calculate the formation process of the anti-atoms, the yield of the fraction leaving the recombination plasma volume and their angular velocity distribution. This model is then benchmarked against data from different antihydrogen experiments. Subsequently, the flux of antihydrogen towards the axial opening angle of a Penning trap is evaluated for its suitability as input beam into a Talbot–Lau matter interferometer. The layout and optimization of the interferometer to measure the acceleration of antihydrogen in the Earth’s gravitational field is numerically calculated. The simulated results can assist experiments aiming to measure the weak equivalence principle of antimatter as proposed by the AEgIS experiment (Testera et al 2015 Hyperfine Interact. 233 13–20). The presented model can further help in the optimization of beam-like antihydrogen sources for CPT invariance tests of antimatter (Kuroda et al 2014 Nat. Commun. 5 3089).

  6. γ-ray Spectroscopy of Proton Drip-Line Nuclei in the A˜130 Region using SPIRAL beams

    Science.gov (United States)

    Stézowski, O.; Guinet, D.; Lautesse, Ph.; Meyer, M.; Redon, N.; Rossé, B.; Schmitt, Ch.; Nolan, P. J.; Boston, A. J.; Cooper, R.; Dimmock, M.; Gros, S.; McGuirck, B.; Paul, E. S.; Petri, M.; Scraggs, H.; Turk, G.; De France, G.; Bhattachasyya, S.; Mukherjee, G.; Rejmund, F.; Rejmund, M.; Savajols, H.; Scheurer, J. N.; Nyakó, B. M.; Gál, J.; Molnár, J.; Timár, J.; Zolnai, L.; Astier, A.; Deloncle, I.; Porquet, M. G.; Prévost, A.; Juhasz, K.; Wadsworth, R.; Joshi, P.; La Rana, G.; Moro, R.; Trotta, M.; Vardaci, E.; Hackman, G.; Ball, G.

    2008-11-01

    A fusion-evaporation experiment has been performed with a SPIRAL 76Kr radioactive beam in order to study the deformation of rare-earth nuclei near the proton drip-line. The experimental setup consisted in the EXOGAM γ-array, coupled to the light-charged particles (LCP) DIAMANT detector and to the VAMOS heavy-ion spectrometer. The difficulties inherent to such measurements are enlightened. The coupling between EXOGAM and DIAMANT has been used to decrease the huge background caused by the radioactivity of the beam. It further permits assigning new γ-ray transitions to specific residual nuclei. A γ-ray belonging to the 130Pm level scheme has thus been observed for the first time.

  7. Off-line production of a sup 7 Be radioactive ion beam

    CERN Document Server

    Gialanella, L; De Cesare, N; D'Onofrio, A; Romano, M; Campajola, L; Formicola, A; Fülöp, Z; Gyürky, G; Imbriani, G; Lubritto, C; Ordine, A; Roca, V; Rogalla, D; Rolfs, C; Russo, M; Sabbarese, C; Somorjai, E; Strieder, F; Terrasi, F; Trautvetter, H P

    2002-01-01

    A sup 7 Be ion beam of several particle pA at 8 MeV has been produced at the TTT3 tandem of the University 'Federico II' in Naples. The sup 7 Be nuclides were formed via the sup 7 Li(p,n) sup 7 Be reaction using a metallic Li target and an 11.4 MeV proton beam of 20 mu A intensity, delivered by the cyclotron in Debrecen. Methods of hot chemistry were used to extract the sup 7 Be nuclides from the Li matrix and to prepare the sup 7 Be cathodes for the ion sputter source of the tandem. Examples of sup 7 Be beam applications are given.

  8. Progress in computer-assisted diagnosis and control of neutral beam lines

    International Nuclear Information System (INIS)

    Theil, E.; Elischer, V.; Fiddler, J.; Jacobs, N.J.D.; Jacobson, V.; Lawhorn, R.; Uber, D.; Wilner, D.

    1980-09-01

    This paper discusses the principles that have guided the development of a computerized diagnostic and control system for both the Neutral Beam Systems Test Facility at Lawrence Berkeley Laboratory and the Doublet III neutral beams at the General Atomic Company. The emphasis is not on the particular details of the implementation, but on general considerations which have influenced the design criteria for the system. Foremost among these are the requirements of an appropriate human interface to the system, and effective use of a relational data base. Examples are used to illustrate how these principles are carried out in practice. A systems view of diagnostic programs is suggested in the light of our experience

  9. Improving the output voltage waveform of an intense electron-beam accelerator based on helical type Blumlein pulse forming line

    Directory of Open Access Journals (Sweden)

    Xin-Bing Cheng

    2010-07-01

    Full Text Available The Blumlein pulse forming line (BPFL consisting of an inner coaxial pulse forming line (PFL and an outer coaxial PFL is widely used in the field of pulsed power, especially for intense electron-beam accelerators (IEBA. The output voltage waveform determines the quality and characteristics of the output beam current of the IEBA. Comparing with the conventional BPFL, an IEBA based on a helical type BPFL can increase the duration of the output voltage in the same geometrical volume. However, for the helical type BPFL, the voltage waveform on a matched load may be distorted which influences the electron-beam quality. In this paper, an IEBA based on helical type BPFL is studied theoretically. Based on telegrapher equations of the BPFL, a formula for the output voltage of IEBA is obtained when the transition section is taken into account, where the transition section is between the middle cylinder of BPFL and the load. From the theoretical analysis, it is found that the wave impedance and transit time of the transition section influence considerably the main pulse voltage waveform at the load, a step is formed in front of the main pulse, and a sharp spike is also formed at the end of the main pulse. In order to get a well-shaped square waveform at the load and to improve the electron-beam quality of such an accelerator, the wave impedance of the transition section should be equal to that of the inner PFL of helical type BPFL and the transit time of the transition section should be designed as short as possible. Experiments performed on an IEBA with the helical type BPFL show reasonable agreement with theoretical analysis.

  10. Ion spectroscopy for improvement of the physical beam model for therapy planning in ion beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Arico, Giulia

    2016-11-23

    Helium and carbon ions enable a more conformal dose distribution, narrower penumbra and higher relative biological effectiveness than photon and proton radiotherapy. However, they may undergo nuclear fragmentation in the patient tissues and the arising secondary fragments affect the delivered biological dose distributions. Currently there is a lack of data regarding ion nuclear fragmentation. One reason is the large size (up to some meters) of the experimental setups required for the investigations. In this thesis a new method is presented, which makes use of versatile pixelated semiconductor detectors (Timepix). This method is based on tracking of single particles and pattern recognition of their signals in the detectors. Measurements were performed at the HIT facility. The mixed radiation field arising from 430 MeV/u carbon ion beams and 221 MeV/u helium ion beams in water and in PMMA targets was investigated. The amounts of primary (carbon or helium) ions detected behind targets with the same water equivalent thickness (WET) were found to be in agreement within the statistical uncertainties. However, more fragments (differences up to 20% in case of H) and narrower lateral particle distributions were measured behind the PMMA than the water targets. The spectra of ions behind tissue surrogates and corresponding water targets with the same WET were analysed. The results obtained with adipose and inner bone surrogates and with the equivalent water phantoms were found to be consistent within the uncertainties. Significant differences in the results were observed in the case of lung and cortical bone surrogates when compared to the water phantoms. The experimental results were compared to FLUKA Monte Carlo simulations. This comparison could contribute to enhance the ion interaction models currently implemented for {sup 12}C and {sup 4}He ion beams.

  11. Model reduction and analysis of a vibrating beam microgyroscope

    KAUST Repository

    Ghommem, Mehdi

    2012-05-08

    The present work is concerned with the nonlinear dynamic analysis of a vibrating beam microgyroscope composed of a rotating cantilever beam with a tip mass at its end. The rigid mass is coupled to two orthogonal electrodes in the drive and sense directions, which are attached to the rotating base. The microbeam is driven by an AC voltage in the drive direction, which induces vibrations in the orthogonal sense direction due to rotation about the microbeam axis. The electrode placed in the sense direction is used to measure the induced motions and extract the underlying angular speed. A reduced-order model of the gyroscope is developed using the method of multiple scales and used to examine its dynamic behavior. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  12. Pulsar average waveforms and hollow cone beam models

    Science.gov (United States)

    Backer, D. C.

    1975-01-01

    An analysis of pulsar average waveforms at radio frequencies from 40 MHz to 15 GHz is presented. The analysis is based on the hypothesis that the observer sees one cut of a hollow-cone beam pattern and that stationary properties of the emission vary over the cone. The distributions of apparent cone widths for different observed forms of the average pulse profiles (single, double/unresolved, double/resolved, triple and multiple) are in modest agreement with a model of a circular hollow-cone beam with random observer-spin axis orientation, a random cone axis-spin axis alignment, and a small range of physical hollow-cone parameters for all objects.

  13. Design of medium energy beam transport line between the RFQ and ...

    Indian Academy of Sciences (India)

    In the present design two pair of quadrupoles, the first pair between the RFQ and the re-buncher and the second pair between the re- buncher and the Linac, are used to take care of the transverse optics requirement. The first pair is required to ensure a beam of small enough size in the experimental chamber as well as in ...

  14. Selection of carbon beam therapy: biophysical models of carbon beam therapy.

    Science.gov (United States)

    Matsufuji, Naruhiro

    2018-03-01

    Variation in the relative biological effectiveness (RBE) within the irradiation field of a carbon beam makes carbon-ion radiotherapy unique and advantageous in delivering the therapeutic dose to a deep-seated tumor, while sparing surrounding normal tissues. However, it is crucial to consider the RBE, not only in designing the dose distribution during treatment planning, but also in analyzing the clinical response retrospectively. At the National Institute of Radiological Sciences, the RBE model was established based on the response of human salivary gland cells. The response was originally handled with a linear-quadratic model, and later with a microdosimetric kinetic model. Retrospective analysis with a tumor-control probability model of non-small cell cancer treatment revealed a steep dose response in the tumor, and that the RBE of the tumor was adequately estimated using the model. A commonly used normal tissue complication probability model has not yet fully been accountable for the variable RBE of carbon ions; however, analysis of rectum injury after prostate cancer treatment suggested a highly serial-organ structure for the rectum, and a steep dose response similar to that observed for tumors.

  15. An analytical model of a clamped sandwich beam under low-impulse mass impact

    Directory of Open Access Journals (Sweden)

    Wen-zheng Jiang

    Full Text Available An analytical model is developed to examine a low impulsive projectile impact on a fully clamped sandwich beams by considering the coupled responses of the core and the face sheets. Firstly, based on the dynamic properties of foam cores, the sandwich beam is modeled as two rigid perfectly-plastic beams connected by rigid perfectly-plastic springs. Different from the previous sandwich beam model, the transverse compression and bending effects of the foam core are considered in the whole deformation process. Based on this model, different coupling mechanism of sandwich beams are constructed so that an analytical solution considering small deformation is derived. The coupled dynamic responses of sandwich beams with different core strengths are investigated. The results indicate that this model improves the prediction accuracy of the responses of the sandwich beams, and is available for the situation when the sandwich beam undergoes moderate global deformation.

  16. High-power, high-brightness pseudospark-produced electron beam driven by improved pulse line accelerator

    International Nuclear Information System (INIS)

    Junbino Zhu; Mingchang Wang; Zhijiang Wang

    1995-01-01

    A high power (200KV), intense current density, low emittance (71mmmrad), high brightness (8x10 10 A/m rad) electron beam was generated in the 10cm long, high-voltage-resistive multi-gap hollow cathode pseudospark chamber filled with 15pa nitrogen and driven by an improved pulse line accelerator. The beam was ejected with the 1mm diameter, the 2.2KA beam current, and the 400ns pulse length, and could propagated 20cm in the drift tube. At a distance of 5cm from the anode it penetrated consecutively an acid-sensitive discoloring film and a 0.05mm-thick copper foil both stuck closely, left 0.6mm and 0.3mm holes on them, respectively. That 10 shots on an acid-sensitive film produced a hole of 1.6mm at 7cm downstream of anode showed its good repeatability. After 60 shots the pseudospark discharge chamber was disassembled and observed that almost no destructive damage traces left on the surfaces of its various electrodes and insulators. But on almost all the surfaces of changeable central hole parts installed on intermediate electrodes there are traces of electron emission from the sides facing the anode and of bombardment on the sides facing the cathode, in contrast with which on the front- and back-surfaces of hollow cathode no visible traces of electron emission from then was observed. In addition, there were different tints, strip-like regions on the side of anode facing the cathode. Another interesting phenomenon was that there were a set of concentric circular or elliptical ring pattern on the acid-sensitive discoloring film got at 5cm from the anode and observed tinder a metallograph. It seems that the pseudospark electron beam is Laminar beam i.e, being possessed of a multi-layer structure, at least in the case of multi-gap pseudospark discharge chamber. It was found experimentally that the quality of pseudospark electron beam is much better than that of the cold-cathode electron beam

  17. Actuator Line Modeling of Wind Turbine Wakes

    DEFF Research Database (Denmark)

    Troldborg, Niels

    2009-01-01

    with the 3D Navier Stokes solver EllipSys3D and a LES turbulence model. Simple models, based on applying body forces in the computational domain, are developed for imposing sheared and turbulent infow and their validity is discussed. A few computations on stand alone turbines are compared to measurements...... inflow shows that besides an expected vertical skewed wake the wake also becomes increasingly asymmetric in the horizontal direction as it is convected downstream. The latter phenomena, which is also often observed in measurements, is argued to be caused by the rotation of the wake. A detailed study...

  18. Comparison of Echo 7 field line length measurements to magnetospheric model predictions

    International Nuclear Information System (INIS)

    Nemzek, R.J.; Winckler, J.R.; Malcolm, P.R.

    1992-01-01

    The Echo 7 sounding rocket experiment injected electron beams on central tail field lines near L = 6.5. Numerous injections returned to the payload as conjugate echoes after mirroring in the southern hemisphere. The authors compare field line lengths calculated from measured conjugate echo bounce times and energies to predictions made by integrating electron trajectories through various magnetospheric models: the Olson-Pfitzer Quiet and Dynamic models and the Tsyganenko-Usmanov model. Although Kp at launch was 3-, quiet time magnetic models est fit the echo measurements. Geosynchronous satellite magnetometer measurements near the Echo 7 field lies during the flight were best modeled by the Olson-Pfitzer Dynamic Model and the Tsyganenko-Usmanov model for Kp = 3. The discrepancy between the models that best fit the Echo 7 data and those that fit the satellite data was most likely due to uncertainties in the small-scale configuration of the magnetospheric models. The field line length measured by the conjugate echoes showed some temporal variation in the magnetic field, also indicated by the satellite magnetometers. This demonstrates the utility an Echo-style experiment could have in substorm studies

  19. A line fiducial method for geometric calibration of cone-beam CT systems with diverse scan trajectories

    Science.gov (United States)

    Jacobson, M. W.; Ketcha, M. D.; Capostagno, S.; Martin, A.; Uneri, A.; Goerres, J.; De Silva, T.; Reaungamornrat, S.; Han, R.; Manbachi, A.; Stayman, J. W.; Vogt, S.; Kleinszig, G.; Siewerdsen, J. H.

    2018-01-01

    Modern cone-beam CT systems, especially C-arms, are capable of diverse source-detector orbits. However, geometric calibration of these systems using conventional configurations of spherical fiducials (BBs) may be challenged for novel source-detector orbits and system geometries. In part, this is because the BB configurations are designed with careful forethought regarding the intended orbit so that BB marker projections do not overlap in projection views. Examples include helical arrangements of BBs (Rougee et al 1993 Proc. SPIE 1897 161-9) such that markers do not overlap in projections acquired from a circular orbit and circular arrangements of BBs (Cho et al 2005 Med. Phys. 32 968-83). As a more general alternative, this work proposes a calibration method based on an array of line-shaped, radio-opaque wire segments. With this method, geometric parameter estimation is accomplished by relating the 3D line equations representing the wires to the 2D line equations of their projections. The use of line fiducials simplifies many challenges with fiducial recognition and extraction in an orbit-independent manner. For example, their projections can overlap only mildly, for any gantry pose, as long as the wires are mutually non-coplanar in 3D. The method was tested in application to circular and non-circular trajectories in simulation and in real orbits executed using a mobile C-arm prototype for cone-beam CT. Results indicated high calibration accuracy, as measured by forward and backprojection/triangulation error metrics. Triangulation errors on the order of microns and backprojected ray deviations uniformly less than 0.2 mm were observed in both real and simulated orbits. Mean forward projection errors less than 0.1 mm were observed in a comprehensive sweep of different C-arm gantry angulations. Finally, successful integration of the method into a CT imaging chain was demonstrated in head phantom scans.

  20. Model-driven and software product line engineering

    CERN Document Server

    Royer, Jean-Claude

    2013-01-01

    Many approaches to creating Software Product Lines have emerged that are based on Model-Driven Engineering. This book introduces both Software Product Lines and Model-Driven Engineering, which have separate success stories in industry, and focuses on the practical combination of them. It describes the challenges and benefits of merging these two software development trends and provides the reader with a novel approach and practical mechanisms to improve software development productivity.The book is aimed at engineers and students who wish to understand and apply software product lines

  1. Theory and Circuit Model for Lossy Coaxial Transmission Line

    Energy Technology Data Exchange (ETDEWEB)

    Genoni, T. C.; Anderson, C. N.; Clark, R. E.; Gansz-Torres, J.; Rose, D. V.; Welch, Dale Robert

    2017-04-01

    The theory of signal propagation in lossy coaxial transmission lines is revisited and new approximate analytic formulas for the line impedance and attenuation are derived. The accuracy of these formulas from DC to 100 GHz is demonstrated by comparison to numerical solutions of the exact field equations. Based on this analysis, a new circuit model is described which accurately reproduces the line response over the entire frequency range. Circuit model calculations are in excellent agreement with the numerical and analytic results, and with finite-difference-time-domain simulations which resolve the skindepths of the conducting walls.

  2. FE Models of GFRP and CFRP Strengthening of Reinforced Concrete Beams

    Directory of Open Access Journals (Sweden)

    Kasidit Chansawat

    2009-01-01

    Full Text Available Three-dimensional finite element (FE models are developed to simulate the behavior of full-scale reinforced concrete beams strengthened with glass and carbon fiber-reinforced polymer sheets (an unstrengthened control beam, a flexural-strengthened beam, a shear-strengthened beam, and a beam with both shear and flexural strengthening. FE models use eight-node isoparametric elements with a smeared cracking approach for the concrete and three-dimensional layered elements to model the FRP composites. Analysis results are compared with data obtained from full-scale beam tests through the linear and nonlinear ranges up to failure. It was found that the FE models could identify qualitatively trends observed in the structural behavior of the full-scale beams. Predicted crack initiation patterns resemble the failure modes observed for the full-scale beam tests.

  3. Progress in computer-assisted diagnosis and control of neutral beam lines

    International Nuclear Information System (INIS)

    Theil, E.; Elischer, V.; Fiddler, J.; Jacobs, N.J.D.; Jacobson, V.; Lawhorn, R.; Uber, D.; Wilner, D.

    1981-01-01

    This paper discusses the principles that have guided the development of a computerized diagnostic and control system for both the Neutral Beam Systems Test Facility at Lawrence Berkeley Laboratory and the Doublet III neutral beams at the General Atomic Company. The emphasis is not on the particular details of the implementation, but on general considerations which have influenced the design criteria for the system. Foremost among these are the requirements of an appropriate human interface to the system, and effective use of a relational data base. Examples are used to illustrate how these principles are carried out in practice. A systems view of diagnostic programs is suggested in the light of our experience. (author)

  4. Dynamic modelling and experimental study of cantilever beam with clearance

    International Nuclear Information System (INIS)

    Li, B; Jin, W; Han, L; He, Z

    2012-01-01

    Clearances occur in almost all mechanical systems, typically such as the clearance between slide plate of gun barrel and guide. Therefore, to study the clearances of mechanisms can be very important to increase the working performance and lifetime of mechanisms. In this paper, rigid dynamic modelling of cantilever with clearance was done according to the subject investigated. In the rigid dynamic modelling, clearance is equivalent to the spring-dashpot model, the impact of beam and boundary face was also taken into consideration. In ADAMS software, the dynamic simulation was carried out according to the model above. The software simulated the movement of cantilever with clearance under external excitation. Research found: When the clearance is larger, the force of impact will become larger. In order to study how the stiffness of the cantilever's supporting part influences natural frequency of the system, A Euler beam which is restricted by a draught spring and a torsion spring at its end was raised. Through numerical calculation, the relationship between natural frequency and stiffness was found. When the value of the stiffness is close to the limit value, the corresponding boundary condition is illustrated. An ADAMS experiment was carried out to check the theory and the simulation.

  5. Tertiary particle production and target optimization of the H2 beam line in the SPS North Area

    CERN Document Server

    AUTHOR|(CDS)2079540; Tellander, Felix; CERN. Geneva. ATS Department

    2016-01-01

    In this note, the tertiary particle yield from secondary targets of different materials placed at the ‘filter’ position of the H2 beam line of SPS North Area are presented. The production is studied for secondary beams of different momenta in the range of 50-250 GeV/c. More specifically, we studied six different targets: two copper cylinders with a radius of 40 mm and lengths of 100 and 300 mm, one solid tungsten cylinder with a radius of 40 mm and a length of 150 mm and three polyethylene cylinders with radius of 40 mm and lengths of 550, 700 and 1000 mm. Eight different momenta of the secondary beam (50, 60, 70, 100, 120, 150, 200 and 250 GeV/c) as well as two different physics lists (QGSP_BIC and FTFP_BERT) have been extensively studied. The purpose of this study is (a) to optimize (using the appropriate filter target) the particle production from the secondary targets as demanded by the experiments (b) investigate the proton production (with respect to the pion production) in the produced tertiary bea...

  6. Beam Cherenkov counter conception for in line identification of 270 GeV/c Σ- Ξ- and Ω-

    International Nuclear Information System (INIS)

    Touillon, R.

    1991-06-01

    The purpose of this thesis is to design a beam Cerenkov counter. This counter will provide an on line identification of the Σ - , Ξ - and Ω - hyperons (270 GeV/c) in the experiment WA89 at CERN. The acceptance of the detector should allow tagging these hyperons in a large momentum range (± 25%) and for a beam divergence up to 250 microrad. The first part of this report is devoted to the physical goals such as the study of charmed baryons, the search of multiquark states, and the determination of hadronic and electromagnetic hyperon radii. The experimental WA89 setup is also presented. The major part deals with the design of the Cerenkov counter. The dimension of the detector, the Cerenkov angle value, the focal length of the spherical mirror, etc... are derived from a Monte-Carlo simulation. Various methods of simple photon detection (gaz detector: TEA, TMAE; solid detectors: PM and Image Intensifier) are investigated. The most performing solution uses two conical mirrors in order to reduce the size of the Cerenkov circles and an image intensifier (which detects the single photon) followed by an optical fiber matrix transmitting the luminous signal to 160 photomultipliers. The on line procedure for calculating the radius of each circle (identification of the particle) is studied in detail. Finally, the optimization of the optical system to achromatize the Cerenkov light is discussed [fr

  7. CT of small objects with synchrotron radiation from the X-26C beam line at the National Synchrotron Light Source

    International Nuclear Information System (INIS)

    Spanne, P.; Rivers, M.L.

    1987-01-01

    CT with spatial resolution in the micrometer range has so far not been possible because of the limited photon fluence rates available from conventional x-ray sources. Synchrotron-generated x-rays now make such high-resolution imaging possible. Experiments to develop CT to the micrometer spatial resolution range have been performed at the X-26C microprobe beam line at the National Synchrotron Light Source at Brookhaven National Laboratory. They have so far yielded images with spatial resolutions down to about 20 μm and show that there is a potential to improve the spatial resolution down to at least 1 μm in imaging of dead objects. This creates an entirely new tool for imaging of microstructures in needle biopsies. Calculations shown that the choice of photon energy is critical in minimizing radiation damage and the imaging time. They also show that CT imaging of small laboratory animals, for example, mice and rats, cna be done with a spatial resolution of the order of 50 μm without inducing any significant radiation damage in the animals. By use of a line-shaped x-ray beam, a photodiode array detector, and standard CAMAC acquisition modules, it should be possible to obtain an image in about 1 minute

  8. The statistics of measurements at a synchrotron beam-line: what use is an additional order of magnitude in precision?

    International Nuclear Information System (INIS)

    Chantler, C.T.; Tran, C.Q.; Paterson, D.; Barnea, Z.; Cookson, D.J.; Argonne National Laboratory, Argonne, IL

    1998-01-01

    The flux, brightness and temporal characteristics of an X-ray source often define the utility of a particular beam-line for a given experiment. However, there are numerous contributions to the statistic of a beam as observed by a particular detector and associated electronics. The significance of these contributions is often neglected, with a consequent loss of precision or accuracy of up to two orders of magnitude. An understanding of the detected statistic for a given arrangement (and the means for optimising this) can make the difference between a successful experiment and a much more limited investigation. We explain the method for measuring a wide variety of important statistical contributions to high accuracy, and draw attention to the statistical consequences of optimised monitoring of upstream signals. We illustrate our theoretical conclusions with the specific example of an X-ray attenuation measurement. Since all X-ray measurements involve either scattering or absorption (or both), the net potential gain in precision is similar for all such experiments, including crystallographic and XAFS determinations. We also use, as an example, observations obtained with ion chambers on a monochromatised bending magnet beam at the Photon Factory, Tsukuba. We determine the absolute flux incident on an experimental setup without measuring the absolute photon count. The approach outlined results in an improvement in precision by almost two orders of magnitude. We point out that the type of statistical analysis described is not only a post-facto diagnostic tool but, by being incorporated into the experiment on-line, can provide a real-time optimising intervention in the measurement process. (authors)

  9. Modeling and measurement of a micro-optic beam deflector

    Science.gov (United States)

    Milster, Tom D.; Wong, J. Nan

    1992-01-01

    The use is studied of a unity-magnification micro-optic beam deflector. The defelector consists of two arrays of positively powered lenslets. The lenslets on each array are arranged in a square grid. Design criteria are based on usefulness in optical data storage devices. The deflector is designed to operate over a + or - 1.6 range of deflection angles. Modeling results are compared with interferometric analysis of the wavefront from a single lenslet pair. The results indicate that the device is nearly diffraction limited, but there are substantial wavefront errors at the edges and corners of the lenslets.

  10. Efficient Beam-Type Structural Modeling of Rotor Blades

    DEFF Research Database (Denmark)

    Couturier, Philippe; Krenk, Steen

    2015-01-01

    The present paper presents two recently developed numerical formulations which enable accurate representation of the static and dynamic behaviour of wind turbine rotor blades using little modeling and computational effort. The first development consists of an intuitive method to extract fully...... coupled six by six cross-section stiffness matrices with limited meshing effort. Secondly, an equilibrium based beam element accepting directly the stiffness matrices and accounting for large variations in geometry and material along the blade is presented. The novel design tools are illustrated...

  11. LEIR impedance model and coherent beam instability observations

    CERN Document Server

    Biancacci, N; Migliorati, M; Rijoff, T L

    2017-01-01

    The LEIR machine is the first synchrotron in the ion ac-celeration chain at CERN and it is responsible to deliverhigh intensity ion beams to the LHC. Following the recentprogress in the understanding of the intensity limitations,detailed studies of the machine impedance started. In thiswork we describe the present LEIR impedance model, detail-ing the contribution to the total longitudinal and transverseimpedance of several machine elements. We then comparethe machine tune shift versus intensity predictions againstmeasurements at injection energy and summarize the co-herent instability observations in the absence of transversefeedback.

  12. A Distribution Line Model for Lightning Overvoltage Studies

    Science.gov (United States)

    Matsuura, Susumu; Noda, Taku; Asakawa, Akira; Yokoyama, Shigeru

    Recently, the focus of lightning protection measures for distribution lines has moved from a nearby lightning stroke to a direct lightning stroke. Studies of direct lightning stroke countermeasures are generally carried out by digital simulations using the EMTP (Electro-Magnetic Transients Program). Thus, components of a distribution line must be modeled appropriately in the EMTP for accurate simulations. The authors have previously clarified the surge response of a distribution line by pulse tests using a reduced-scale distribution line model. In this paper, first, the results of the pulse tests are simulated in the EMTP using a conventional model which represents a distribution pole by a single lossless distributed-parameter line model, and comparisons with the test results show that transient overvoltages generated at the insulators cannot accurately be reproduced by the conventional model. This indicates that a special treatment is required to represent the transient response of a distribution pole and wires. Then, this paper proposes new EMTP models of the pole and wires which can reproduce the transient overvoltages at the insulators. The parameter values of the proposed models can be determined based on a pulse test result.

  13. A mathematical model for camera calibration based on straight lines

    Directory of Open Access Journals (Sweden)

    Antonio M. G. Tommaselli

    2005-12-01

    Full Text Available In other to facilitate the automation of camera calibration process, a mathematical model using straight lines was developed, which is based on the equivalent planes mathematical model. Parameter estimation of the developed model is achieved by the Least Squares Method with Conditions and Observations. The same method of adjustment was used to implement camera calibration with bundles, which is based on points. Experiments using simulated and real data have shown that the developed model based on straight lines gives results comparable to the conventional method with points. Details concerning the mathematical development of the model and experiments with simulated and real data will be presented and the results with both methods of camera calibration, with straight lines and with points, will be compared.

  14. Initiating Events Modeling for On-Line Risk Monitoring Application

    International Nuclear Information System (INIS)

    Simic, Z.; Mikulicic, V.

    1998-01-01

    In order to make on-line risk monitoring application of Probabilistic Risk Assessment more complete and realistic, a special attention need to be dedicated to initiating events modeling. Two different issues are of special importance: one is how to model initiating events frequency according to current plant configuration (equipment alignment and out of service status) and operating condition (weather and various activities), and the second is how to preserve dependencies between initiating events model and rest of PRA model. First, the paper will discuss how initiating events can be treated in on-line risk monitoring application. Second, practical example of initiating events modeling in EPRI's Equipment Out of Service on-line monitoring tool will be presented. Gains from application and possible improvements will be discussed in conclusion. (author)

  15. A model of polarized-beam AGS in the ray-tracing code Zgoubi

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ahrens, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brown, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Dutheil, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Glenn, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Shoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-07-12

    A model of the Alternating Gradient Synchrotron, based on the AGS snapramps, has been developed in the stepwise ray-tracing code Zgoubi. It has been used over the past 5 years in a number of accelerator studies aimed at enhancing RHIC proton beam polarization. It is also used to study and optimize proton and Helion beam polarization in view of future RHIC and eRHIC programs. The AGS model in Zgoubi is operational on-line via three different applications, ’ZgoubiFromSnaprampCmd’, ’AgsZgoubiModel’ and ’AgsModelViewer’, with the latter two essentially interfaces to the former which is the actual model ’engine’. All three commands are available from the controls system application launcher in the AGS ’StartUp’ menu, or from eponymous commands on shell terminals. Main aspects of the model and of its operation are presented in this technical note, brief excerpts from various studies performed so far are given for illustration, means and methods entering in ZgoubiFromSnaprampCmd are developed further in appendix.

  16. Nebular Continuum and Line Emission in Stellar Population Synthesis Models

    Science.gov (United States)

    Byler, Nell; Dalcanton, Julianne J.; Conroy, Charlie; Johnson, Benjamin D.

    2017-05-01

    Accounting for nebular emission when modeling galaxy spectral energy distributions (SEDs) is important, as both line and continuum emissions can contribute significantly to the total observed flux. In this work, we present a new nebular emission model integrated within the Flexible Stellar Population Synthesis code that computes the line and continuum emission for complex stellar populations using the photoionization code Cloudy. The self-consistent coupling of the nebular emission to the matched ionizing spectrum produces emission line intensities that correctly scale with the stellar population as a function of age and metallicity. This more complete model of galaxy SEDs will improve estimates of global gas properties derived with diagnostic diagrams, star formation rates based on Hα, and physical properties derived from broadband photometry. Our models agree well with results from other photoionization models and are able to reproduce observed emission from H II regions and star-forming galaxies. Our models show improved agreement with the observed H II regions in the Ne III/O II plane and show satisfactory agreement with He II emission from z = 2 galaxies, when including rotating stellar models. Models including post-asymptotic giant branch stars are able to reproduce line ratios consistent with low-ionization emission regions. The models are integrated into current versions of FSPS and include self-consistent nebular emission predictions for MIST and Padova+Geneva evolutionary tracks.

  17. Multikanban model for disassembly line with demand fluctuation

    Science.gov (United States)

    Udomsawat, Gun; Gupta, Surendra M.; Al-Turki, Yousef A. Y.

    2004-02-01

    In recent years, the continuous growth in consumer waste and dwindling natural resources has seriously threatened the environment. Realizing this, several countries have passed regulations that force manufacturers not only to manufacture environmentally conscious products, but also to take back their used products from consumers so that the components and materials recovered from the products may be reused and/or recycled. Disassembly plays an important role in product recovery. A disassembly line is perhaps the most suitable setting for disassembly of products in large quantities. Because a disassembly line has a tendency to generate excessive inventory, employing a kanban system can reduce the inventory level and let the system run more efficiently. A disassembly line is quite different from an assembly line. For example, not only can the demand arrive at the last station, it can also arrive at any of the other stations in the system. The demand for a component on the disassembly line could fluctuate widely. In fact, there are many other complicating matters that need to be considered to implement the concept of kanbans in such an environment. In this paper, we discuss the complications that are unique to a disassembly line. We discuss the complications in utilizing the conventional production control mechanisms in a disassembly line setting. We then show how to overcome them by implementing kanbans in a disassembly line setting with demand fluctuation and introduce the concept of multi-kanban mechanism. We demonstrate its effectiveness using a simulation model. An example is presented to illustrate the concept.

  18. Transmission Delay Modeling of Packet Communication over Digital Subscriber Line

    Directory of Open Access Journals (Sweden)

    Jiri Vodrazka

    2013-01-01

    Full Text Available Certain multimedia and voice services, such as VoIP, IPTV, etc., are significantly delay sensitive and their performance is influenced by the overall transmission delay and its variance. One of the most common solutions used in access networks are xDSL lines, especially ADSL2+ or VDSL2. Although these subscriber lines also use packet communication, there are several differences and mechanisms, which influence their resulting delay. Their delay characteristics are also dependent on the individual settings of each xDSL provider, therefore we decided to investigate this area for typical commercially available lines in Czech Republic. Based on the measured values and experiments with real ADSL2+ lines we also developed a potential modeling method, which is presented in this article as well. The parameters for packet jitter based on the generalized Pareto distribution were modeled.

  19. Constructing Poverty Lines in Croatia Using Kakwani’s Model

    Directory of Open Access Journals (Sweden)

    Marinko Škare

    2017-06-01

    Full Text Available This paper presents a new model for defining the poverty line as a possible candidate for the construction of a new official poverty line in Croatia. The model, based on Kakwani’s (2010 approach (nutrition-based anchor, uses consumer theory as the basis for defining food and non-food poverty lines. In Croatia, various alternative poverty indicators have been developed to define the official poverty line. To ensure international comparability and consistency, the poverty threshold expressed in local currency by applying the exchange rate of currencies’ purchasing power (PPP is expressed in international dollars. It is important to ensure implementation of redistributive policies, maximization of market efficiency, and increased social justice. All this policy goals and instruments heavily depend on efficient and precise poverty measurement methods.

  20. A model for Hsub(α) and Hsub(β) emission from a high power hydrogen beam

    International Nuclear Information System (INIS)

    Bracco, G.; Ramette, J.

    1980-07-01

    Hsub(α) and Hsub(β) emission from an high power hydrogen beam has been simulated by means of a computer code in order to discuss the role of various parameters (acceleration energy, pressure, impact decay) on the measured intensities. A comparison has been performed with other simplified models and conversion factors are provided to transform the measured line intensity ratios into extracted species proportions

  1. The WARP Code: Modeling High Intensity Ion Beams

    Science.gov (United States)

    Grote, David P.; Friedman, Alex; Vay, Jean-Luc; Haber, Irving

    2005-03-01

    The Warp code, developed for heavy-ion driven inertial fusion energy studies, is used to model high intensity ion (and electron) beams. Significant capability has been incorporated in Warp, allowing nearly all sections of an accelerator to be modeled, beginning with the source. Warp has as its core an explicit, three-dimensional, particle-in-cell model. Alongside this is a rich set of tools for describing the applied fields of the accelerator lattice, and embedded conducting surfaces (which are captured at sub-grid resolution). Also incorporated are models with reduced dimensionality: an axisymmetric model and a transverse "slice" model. The code takes advantage of modern programming techniques, including object orientation, parallelism, and scripting (via Python). It is at the forefront in the use of the computational technique of adaptive mesh refinement, which has been particularly successful in the area of diode and injector modeling, both steady-state and time-dependent. In the presentation, some of the major aspects of Warp will be overviewed, especially those that could be useful in modeling ECR sources. Warp has been benchmarked against both theory and experiment. Recent results will be presented showing good agreement of Warp with experimental results from the STS500 injector test stand. Additional information can be found on the web page http://hif.lbl.gov/theory/WARP_summary.html.

  2. The WARP Code: Modeling High Intensity Ion Beams

    International Nuclear Information System (INIS)

    Grote, David P.; Friedman, Alex; Vay, Jean-Luc; Haber, Irving

    2005-01-01

    The Warp code, developed for heavy-ion driven inertial fusion energy studies, is used to model high intensity ion (and electron) beams. Significant capability has been incorporated in Warp, allowing nearly all sections of an accelerator to be modeled, beginning with the source. Warp has as its core an explicit, three-dimensional, particle-in-cell model. Alongside this is a rich set of tools for describing the applied fields of the accelerator lattice, and embedded conducting surfaces (which are captured at sub-grid resolution). Also incorporated are models with reduced dimensionality: an axisymmetric model and a transverse ''slice'' model. The code takes advantage of modern programming techniques, including object orientation, parallelism, and scripting (via Python). It is at the forefront in the use of the computational technique of adaptive mesh refinement, which has been particularly successful in the area of diode and injector modeling, both steady-state and time-dependent. In the presentation, some of the major aspects of Warp will be overviewed, especially those that could be useful in modeling ECR sources. Warp has been benchmarked against both theory and experiment. Recent results will be presented showing good agreement of Warp with experimental results from the STS500 injector test stand

  3. Modeling of Heat Transfer in LDConverter (BOF) Lining

    OpenAIRE

    Jahan, Georgina

    2012-01-01

    During the production of steel in the LD converter the refractory lining is exposed to high temperature emulsion of steel, slag and gas. It protects the steel body of the vessel to come in contact with the molten steel.The main purpose of this work was to observe the temperature distribution profile in converter refractory lining which is very important to understand the life of the refractory lining of the LD converter.In this study, a three dimensional (3D) heat transfer model for the refra...

  4. Modeling of the temperature field of the casting ladle lining

    Science.gov (United States)

    Zabolotsky, A. V.

    2011-03-01

    We propose a method for calculating the temperature field of the casting ladle lining by a modified relaxation method. Given such initial data as the metal temperature in the ladle, the ambient temperature, and the lining structure, this method permits calculating the stationary temperature fields both inside the lining and on the surface of the ladle jacket. The model was tested by comparing experimentally measured temperature values on the surface of the ladle jacket with calculated temperatures. A satisfactory agreement between calculated and experimental temperature values of the ladle surface has been obtained.

  5. Mathematical analysis on a model for the rectangular cantilever beam

    International Nuclear Information System (INIS)

    Tsai, S.-H.; Kan, H.-C.

    2007-01-01

    The mechanical model for the rectangular cantilever beam proposed by Zhang et al is solved analytically by the series solution with mathematical properties investigated in detail. The derived series solution is proved convergent, and restrained only by the small deflection presumed by the Euler-Bernoulli beam theorem, and is applicable for calculating the deflection and curvature for any value of the exerted axial stress. The formulae estimating the accuracy of the coefficients and the series solution are developed from Stirling's approximation for the gamma function. The condition on the axial stress is developed, by which the genuinely nonlinear curvature can be approximated by a linear function and the deflection can be calculated from the boundary condition by a cubic polynomial. The additional redundant boundary condition used in Zhang's work is discussed, which should be removed since it fails to fit the model by inducing errors for calculating the deflection and the curvature. The present series solution approach provides formal deflection-stress and curvature-stress relations for the design of a MEMS micro-cantilever system as a bio-detection device. For self-assembly applications, the adsorbing material can be identified by solving the exerted axial stress from the series solution

  6. Analytical Model for High Impedance Fault Analysis in Transmission Lines

    Directory of Open Access Journals (Sweden)

    S. Maximov

    2014-01-01

    Full Text Available A high impedance fault (HIF normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

  7. Modeling of polarization phenomena due to RF sheaths and electron beams in magnetized plasma

    International Nuclear Information System (INIS)

    Faudot, E.

    2005-01-01

    This work investigates the problematic of hot spots induced by accelerated particle fluxes in tokamaks. It is shown that the polarization due to sheaths in the edge plasma in which an electron beam at a high level of energy is injected, can reach several hundreds volts and thus extend the deposition area. The notion of obstructed sheath is introduced and explains the acceleration of energy deposition by the decreasing of the sheath potential. Then, a 2-dimensional fluid modeling of flux tubes in front of ICRF antennae allows us to calculate the rectified potentials taking into account RF polarization currents transverse to magnetic field lines. The 2-dimensional fluid code designed validates the analytical results which show that the DC rectified potential is 50% greater with polarization currents than without. Finally, the simultaneous application of an electron beam and a RF potential reveals that the potentials due to each phenomenon are additives when RF potential is much greater than beam polarization. The density depletion of polarized flux tubes in 2-dimensional PIC (particles in cells) simulations is characterized but not yet explained. (author)

  8. Beam Diagnosis and Lattice Modeling of the Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaobiao [Indiana Univ., Bloomington, IN (United States)

    2005-09-01

    A realistic lattice model is a fundamental basis for the operation of a synchrotron. In this study various beam-based measurements, including orbit response matrix (ORM) and BPM turn-by-turn data are used to verify and calibrate the lattice model of the Fermilab Booster. In the ORM study, despite the strong correlation between the gradient parameters of adjacent magnets which prevents a full determination of the model parameters, an equivalent lattice model is obtained by imposing appropriate constraints. The fitted gradient errors of the focusing magnets are within the design tolerance and the results point to the orbit offsets in the sextupole field as the source of gradient errors. A new method, the independent component analysis (ICA) is introduced to analyze multiple BPM turn-by-turn data taken simultaneously around a synchrotron. This method makes use of the redundancy of the data and the time correlation of the source signals to isolate various components, such as betatron motion and synchrotron motion, from raw BPM data. By extracting clean coherent betatron motion from noisy data and separates out the betatron normal modes when there is linear coupling, the ICA method provides a convenient means to measure the beta functions and betatron phase advances. It also separates synchrotron motion from the BPM samples for dispersion function measurement. The ICA method has the capability to separate other perturbation signals and is robust over the contamination of bad BPMs. The application of the ICA method to the Booster has enabled the measurement of the linear lattice functions which are used to verify the existing lattice model. The transverse impedance and chromaticity are measured from turn-by-turn data using high precision tune measurements. Synchrotron motion is also observed in the BPM data. The emittance growth of the Booster is also studied by data taken with ion profile monitor (IPM). Sources of emittance growth are examined and an approach to cure

  9. Model for estimating of population abundance using line transect sampling

    Science.gov (United States)

    Abdulraqeb Abdullah Saeed, Gamil; Muhammad, Noryanti; Zun Liang, Chuan; Yusoff, Wan Nur Syahidah Wan; Zuki Salleh, Mohd

    2017-09-01

    Today, many studies use the nonparametric methods for estimating objects abundance, for the simplicity, the parametric methods are widely used by biometricians. This paper is designed to present the proposed model for estimating of population abundance using line transect technique. The proposed model is appealing because it is strictly monotonically decreasing with perpendicular distance and it satisfies the shoulder conditions. The statistical properties and inference of the proposed model are discussed. In the presented detection function, theoretically, the proposed model is satisfied the line transect assumption, that leads us to study the performance of this model. We use this model as a reference for the future research of density estimation. In this paper we also study the assumption of the detection function and introduce the corresponding model in order to apply the simulation in future work.

  10. On beam shaping of the field radiated by a line source coupled to finite or infinite photonic crystals.

    Science.gov (United States)

    Ceccuzzi, Silvio; Jandieri, Vakhtang; Baccarelli, Paolo; Ponti, Cristina; Schettini, Giuseppe

    2016-04-01

    Comparison of the beam-shaping effect of a field radiated by a line source, when an ideal infinite structure constituted by two photonic crystals and an actual finite one are considered, has been carried out by means of two different methods. The lattice sums technique combined with the generalized reflection matrix method is used to rigorously investigate the radiation from the infinite photonic crystals, whereas radiation from crystals composed of a finite number of rods along the layers is analyzed using the cylindrical-wave approach. A directive radiation is observed with the line source embedded in the structure. With an increased separation distance between the crystals, a significant edge diffraction appears that provides the main radiation mechanism in the finite layout. Suitable absorbers are implemented to reduce the above-mentioned diffraction and the reflections at the boundaries, thus obtaining good agreement between radiation patterns of a localized line source coupled to finite and infinite photonic crystals, when the number of periods of the finite structure is properly chosen.

  11. Modeling of Cracked Beams by the Experimental Design Method

    Directory of Open Access Journals (Sweden)

    M. Serier

    Full Text Available Abstract The understanding of phenomena, no matter their nature is based on the experimental results found. In the most cases, this requires an important number of tests in order to put a reliable and useful observation served into solving the technical problems subsequently. This paper is based on independent and variables combination resulting from experimentation in a mathematical formulation. Indeed, mathematical modeling gives us the advantage to optimize and predict the right choices without passing each case by the experiment. In this work we plan to apply the experimental design method on the experimental results found by (Deokar, A, 2011, concerning the effect of the size and position of a crack on the measured frequency of a beam console, and validating the mathematical model to predict other frequencies

  12. Rigorous theoretical derivation of lumped models to transmission line systems

    International Nuclear Information System (INIS)

    Zhao Jixiang

    2012-01-01

    By virtue of the negative electric parameter concept, i.e. negative lumped resistance, inductance, conductance and capacitance (N-RLGC), the lumped equivalent models of transmission line systems, including the circuit model, two-port π-network and T-network, are given. We start from the N-segment-ladder-like equivalent networks composed distributed parameters, and achieve the input impedance in the form of a continued fraction. Utilizing the continued fraction theory, the expressions of input impedance are obtained under three kinds of extreme cases, i.e. the load impedances are equal to zero, infinity and characteristic impedance, respectively. When the number of segment N is limited to infinity, they are transformed to lumped elements. Comparison between the distributed model and lumped model of transmission lines, the expression of tanh γd, which is the key term in the transmission line equations, are obtained by RLGC, furthermore, according to input admittance, admittance matrix and ABCD matrix of transmission lines, the lumped equivalent circuit models, π-networks and T-networks have been given. The models are verified in the frequency and time domain, respectively, showing that the models are accurate and efficient. (semiconductor integrated circuits)

  13. Single-bunch beam breakup in a dielectric-lined waveguide

    International Nuclear Information System (INIS)

    Ng, King-Yuen.

    1992-08-01

    We examine beam breakup of a 100 nC I mm-long (rms) source bunch inside a cylindrical dielectric waveguide, with dielectric ε = 2.65 filling the radius between 7.5 and 9.0 mm. Only ∼ 78% of the bunch with an initial offset of 0.3 mm survives the passage of the 3.75 m waveguide. The loss is mainly due to the large deflections of some particles that are slowed down to nearly zero velocity. As a result, quadrupole focussing of any sort will not help. However, if the waveguide is shortened to 3.3 m, the loss reduces to only 5.5%

  14. Transport and dosimetric solutions for the ELIMED laser-driven beam line

    Czech Academy of Sciences Publication Activity Database

    Cirrone, G.A.P.; Romano, F.; Scuderi, Valentina; Amato, A.; Candiano, G.; Cuttone, G.; Giove, d.; Korn, Georg; Krása, Josef; Leanza, R.; Manna, R.; Maggiore, M.; Marchese, V.; Margarone, Daniele; Milluzzo, G.; Petringa, G.; Sabini, M.G.; Schillaci, F.; Tramontana, A.; Valastro, L.; Velyhan, Andriy

    2015-01-01

    Roč. 796, Oct (2015), s. 99-103 ISSN 0168-9002 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE2.3.20.0279; GA MŠk EE2.3.30.0057 Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; LaserZdroj (OP VK 3)(XE) CZ.1.07/2.3.00/20.0279; OP VK 4 POSTDOK(XE) CZ.1.07/2.3.00/30.0057 Institutional support: RVO:68378271 Keywords : laser-driven ion * beam- transport * Faraday cup dosimetry * absolute dosimetry Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.200, year: 2015

  15. Rigorous Model Reduction for a Damped-Forced Nonlinear Beam Model: An Infinite-Dimensional Analysis

    Science.gov (United States)

    Kogelbauer, Florian; Haller, George

    2018-01-01

    We use invariant manifold results on Banach spaces to conclude the existence of spectral submanifolds (SSMs) in a class of nonlinear, externally forced beam oscillations. SSMs are the smoothest nonlinear extensions of spectral subspaces of the linearized beam equation. Reduction in the governing PDE to SSMs provides an explicit low-dimensional model which captures the correct asymptotics of the full, infinite-dimensional dynamics. Our approach is general enough to admit extensions to other types of continuum vibrations. The model-reduction procedure we employ also gives guidelines for a mathematically self-consistent modeling of damping in PDEs describing structural vibrations.

  16. Some Results On The Modelling Of TSS Manufacturing Lines

    Directory of Open Access Journals (Sweden)

    Viorel MÎNZU

    2000-12-01

    Full Text Available This paper deals with the modelling of a particular class of manufacturing lines, governed by a decentralised control strategy so that they balance themselves. Such lines are known as “bucket brigades” and also as “TSS lines”, after their first implementation, at Toyota, in the 70’s. A first study of their behaviour was based upon modelling as stochastic dynamic systems, which emphasised, in the frame of the so-called “Normative Model”, a sufficient condition for self-balancing, that means for autonomous functioning at a steady production rate (stationary behaviour. Under some particular conditions, a simulation analysis of TSS lines could be made on non-linear block diagrams, showing that the state trajectories are piecewise continuous in between occurrences of certain discrete events, which determine their discontinuity. TSS lines may therefore be modelled as hybrid dynamic systems, more specific, with autonomous switching and autonomous impulses (jumps. A stability analysis of such manufacturing lines is allowed by modelling them as hybrid dynamic systems with discontinuous motions.

  17. Enhancing the accelerated beam current in the booster synchrotron ...

    Indian Academy of Sciences (India)

    journal of. April 2016 physics pp. 847–860. Enhancing the accelerated beam current in the booster synchrotron by optimizing the transport line beam propagation ... method. The measured parameters have been used for beam transport line optimization and twiss parameters ... model WATEC 127 LH (CCIR) has been used.

  18. Aspect-Oriented Model-Driven Software Product Line Engineering

    Science.gov (United States)

    Groher, Iris; Voelter, Markus

    Software product line engineering aims to reduce development time, effort, cost, and complexity by taking advantage of the commonality within a portfolio of similar products. The effectiveness of a software product line approach directly depends on how well feature variability within the portfolio is implemented and managed throughout the development lifecycle, from early analysis through maintenance and evolution. This article presents an approach that facilitates variability implementation, management, and tracing by integrating model-driven and aspect-oriented software development. Features are separated in models and composed of aspect-oriented composition techniques on model level. Model transformations support the transition from problem to solution space models. Aspect-oriented techniques enable the explicit expression and modularization of variability on model, template, and code level. The presented concepts are illustrated with a case study of a home automation system.

  19. Integrated on-line accelerator modeling at CEBAF

    International Nuclear Information System (INIS)

    Bowling, B.A.; Shoaee, H.; Van Zeijts, J.; Witherspoon, S.; Watson, W.

    1995-01-01

    An on-line accelerator modeling facility is currently under development at CEBAF. The model server, which is integrated with the EPICS control system, provides coupled and 2nd-order matrices for the entire accelerator, and forms the foundation for automated model- based control and diagnostic applications. Four types of machine models are provided, including design, golden or certified, live, and scratch or simulated model. Provisions are also made for the use of multiple lattice modeling programs such as DIMAD, PARMELA, and TLIE. Design and implementation details are discussed. 2 refs., 4 figs

  20. Dynamic thermal model of photovoltaic cell illuminated by laser beam

    Science.gov (United States)

    Liu, Xiaoguang; Hua, Wenshen; Guo, Tong

    2015-07-01

    Photovoltaic cell is one of the most important components of laser powered unmanned aerial vehicle. Illuminated by high power laser beam, photovoltaic cell temperature increases significantly, which leads to efficiency drop, or even physical damage. To avoid such situation, the temperature of photovoltaic cell must be predicted precisely. A dynamic thermal model of photovoltaic cell is established in this paper, and the relationships between photovoltaic cell temperature and laser power, wind speed, ambient temperature are also analyzed. Simulation result indicates that illuminated by a laser beam, the temperature of photovoltaic cell rises gradually and reach to a constant maximum value. There is an approximately linear rise in photovoltaic cell temperature as the laser flux gets higher. The higher wind speed is, the stronger forced convection is, and then the lower photovoltaic cell temperature is. But the relationship between photovoltaic cell temperature and wind speed is not linear. Photovoltaic cell temperature is proportional to the ambient temperature. For each increase of 1 degree of ambient temperature, there is approximate 1 degree increase in photovoltaic cell temperature. The result will provide fundamentals to take reasonable measures to control photovoltaic cell temperature.

  1. Structural modelling of composite beams with application to wind turbine rotor blades

    DEFF Research Database (Denmark)

    Couturier, Philippe

    The ever changing structure and growing size of wind turbine blades put focus on the accuracy and flexibility of design tools. The present thesis is organized in four parts - all concerning the development of efficient computational methods for the structural modelling of composite beams which...... represented within the elements. A post processing scheme is also presented to recover inter laminar stresses via equilibrium equations of 3D elasticity derived in the laminate coordinate system.In the final part of the thesis a flexible method for analysing two types of instabilities associated with bending...... longitudinal stresses is modelled with a Finite Strip buckling analysis based on the deformed cross-section. The analysis is well suited for early stages of design as it only requires a simple 2D line mesh of the cross-section....

  2. Research and Design of a Sample Heater for Beam Line 6-2c Transmission X-ray Microscope

    Energy Technology Data Exchange (ETDEWEB)

    Policht, Veronica; /Loyola U., Chicago /SLAC

    2012-08-27

    There exists a need for environmental control of samples to be imaged by the Transmission X-Ray Microscope (TXM) at the SSRLs Beam Line 6-2c. In order to observe heat-driven chemical or morphological changes that normally occur in situ, microscopes require an additional component that effectively heats a given sample without heating any of the microscope elements. The confinement of the heat and other concerns about the heaters integrity limit which type of heater is appropriate for the TXM. The bulk of this research project entails researching different heating methods used previously in microscopes, but also in other industrial applications, with the goal of determining the best-fitting method, and finally in designing a preliminary sample heater.

  3. A Transmission Line Model for the Spherical Beltrami Problem

    Science.gov (United States)

    Papageorgiou, C. D.; Raptis, T. E.

    We extend a previously introduced model for finding eigenvalues and eigenfunctions of PDEs with a certain natural symmetry set based on an analysis of an equivalent transmission line circuit. This was previously applied with success in the case of optical fibers [8], [9] as well as in the case of a linear Schroedinger equation [10], [11] and recently in the case of spherical symmetry (Ball Lightning) [12]. We explore the interpretation of eigenvalues as resonances of the corresponding transmission line model. We use the generic Beltrami problem of non-constant eigen-vorticity in spherical coordinates as a test bed and we locate the bound states and the eigen-vorticity functions.

  4. Superconducting magnets at Brookhaven National Laboratory. AGS high energy unseparated beam line dipoles and ISABELLE ring magnet prototypes

    International Nuclear Information System (INIS)

    McInturff, A.D.

    1977-01-01

    In the last two years the ISABELLE Division of Brookhaven National Laboratory has constructed various superconducting dipoles in their search for the optimum magnet on which to base the storage ring design. Data taken for two of the larger size systems that have been completed to date are reported. The first system is composed of four large superconducting dipoles used in the 20 0 bend of the multiparticle spectrometer (MPS) beam line of the 30 GeV Alternating Gradient Synchrotron (AGS). These 25 cm inner diameter (i.d.) dipoles bend the High Energy Unseparated Beam (HEUB) 5 0 each and have a stored energy of one Megajoule which can and is internally dissipated. The four magnets have operated in excess of 4.0 T after a few training quenches. The single layer cosine theta turns distribution dipoles have been operating under the direction of the ''AGS'' control computer for about six months. These magnets are of a similar design even though certain details are not identical to the ''ISABELLE'' prototype ring magnets. During the same time period, six full-size ring dipoles and one ring quadrupole have been completed with a seventh dipole under construction

  5. Theoretical models of magnetic field line merging. I

    International Nuclear Information System (INIS)

    Vasyliunas, V.M.

    1975-01-01

    Models of magnetic field line merging that consider processes in a limited region around the magnetic X line, within which the external magnetic fields are roughly uniform and antiparallel, are reviewed. Part I describes the concept of magnetic merging and then considers the models based on a hydromagnetic approach. The models developed by Sweet and Parker, by Petschek, and by Sonnerup and Yeh and Axford are shown to be fundamentally consistent, representing different aspects of the same problem. The model of Sweet and Parker describes the small region around the neutral line where magnetic field diffusion is the dominant process. The inclusion of inertial as well as finite resistivity effects allows an extension of their model to collisionless plasmas. Petschek's model represents a system with a boundary condition of uniform field at the sides; it has been extended and formulated in a mathematically precise manner. The nonsingular model of Sonnerup and of Yeh and Axford has special boundary conditions at the sides producing localized slow mode MHD expansion fans in the external flow; the singular models and the compressible similarity models are physically unrealizable. The maximum merging rate corresponds to flow into the diffusion region of the local Alfven speed, which, however, can be made arbitrarily large by slow mode MHD expansion if suitable boundary condi []ions are present. (auth)

  6. Understanding Mammalian Germ Line Development with In Vitro Models.

    Science.gov (United States)

    Martínez-Arroyo, Ana M; Míguez-Forján, Jose M; Remohí, Jose; Pellicer, Antonio; Medrano, Jose V

    2015-09-15

    Germ line development is crucial in organisms with sexual reproduction to complete their life cycle. In mammals, knowledge about germ line development is based mainly on the mouse model, in which genetic and epigenetic events are well described. However, little is known about how germ line development is orchestrated in humans, especially in the earliest stages. New findings derived from human in vitro models to obtain germ cells can shed light on these questions. This comprehensive review summarizes the current knowledge about mammalian germ line development, emphasizing the state of the art obtained from in vitro models for germ cell-like cell derivation. Current knowledge of the pluripotency cycle and germ cell specification has allowed different in vitro strategies to obtain germ cells with proven functionality in mouse models. Several reports during the last 10 years show that in vitro germ cell derivation with proven functionality to generate a healthy offspring is possible in mice. However, differences in the embryo development and pluripotency potential between human and mouse make it difficult to extrapolate these results. Further efforts on both human and mouse in vitro models to obtain germ cells from pluripotent stem cells may help to elucidate how human physiological events take place; therefore, therapeutic strategies can also be considered.

  7. Second-order moments of Schell-model beams with various correlation functions in atmospheric turbulence.

    Science.gov (United States)

    Zheng, Guo; Wang, Jue; Wang, Lin; Zhou, Muchun; Xin, Yu; Song, Minmin

    2017-11-15

    The general formulae for second-order moments of Schell-model beams with various correlation functions in atmospheric turbulence are derived and validated by the Bessel-Gaussian Schell-model beams and cosine-Gaussian-correlated Schell-model beams. Our finding shows that the second-order moments of partially coherent Schell-model beams are related to the second-order partial derivatives of source spectral degree of coherence at the origin. The formulae we provide are much more convenient to analyze and research propagation problems in turbulence.

  8. Duplication Detection When Evolving Feature Models of Software Product Lines

    Directory of Open Access Journals (Sweden)

    Amal Khtira

    2015-10-01

    Full Text Available After the derivation of specific applications from a software product line, the applications keep evolving with respect to new customer’s requirements. In general, evolutions in most industrial projects are expressed using natural language, because it is the easiest and the most flexible way for customers to express their needs. However, the use of this means of communication has shown its limits in detecting defects, such as inconsistency and duplication, when evolving the existing models of the software product line. The aim of this paper is to transform the natural language specifications of new evolutions into a more formal representation using natural language processing. Then, an algorithm is proposed to automatically detect duplication between these specifications and the existing product line feature models. In order to instantiate the proposed solution, a tool is developed to automatize the two operations.

  9. Characterization of uniform scanning proton beams with analytical models

    Science.gov (United States)

    Demez, Nebi

    Tissue equivalent phantoms have an important place in radiation therapy planning and delivery. They have been manufactured for use in conventional radiotherapy. Their tissue equivalency for proton beams is currently in active investigation. The Bragg-Kleeman rule was used to calculate water equivalent thickness (WET) for available tissue equivalent phantoms from CIRS (Norfolk, VA, USA). WET's of those phantoms were also measured using proton beams at Hampton University Proton Therapy Institute (HUPTI). WET measurements and calculations are in good agreement within ˜1% accuracy except for high Z phantoms. Proton beams were also characterized with an analytical proton dose calculation model, Proton Loss Model (PLM) [26], to investigate protons interactions in water and those phantoms. Depth-dose and lateral dose profiles of protons in water and in those phantoms were calculated, measured, and compared. Water Equivalent Spreadness (WES) was also investigated for those phantoms using the formula for scattering power ratio. Because WES is independent of incident energy of protons, it is possible to estimate spreadness of protons in different media by just knowing WES. Measurements are usually taken for configuration of the treatment planning system (TPS). This study attempted to achieve commissioning data for uniform scanning proton planning with analytical methods, PLM, which have been verified with published measurements and Monte Carlo calculations. Depth doses and lateral profiles calculated by PLM were compared with measurements via the gamma analysis method. While gamma analysis shows that depth doses are in >90% agreement with measured depth doses, the agreement falls to <80% for some lateral profiles. PLM data were imported into the TPS (PLM-TPS). PLM-TPS was tested with different patient cases. The PLM-TPS treatment plans for 5 prostate cases show acceptable agreement. The Planning Treatment Volume (PTV) coverage was 100 % with PLM-TPS except for one case in

  10. Sonic beam model of Newton’s cradle

    Science.gov (United States)

    Menger, Fredric M.; Rizvi, Syed A. A.

    2016-07-01

    The motions of Newton’s cradle, consisting of several steel balls hanging side-by-side, have been analysed in terms of a sound pulse that travels via points of contact among the balls. This presupposes a focused energy beam. When the pulse reaches the fifth and final ball, the energy disperses and dislocates the ball with a trajectory equivalent to that of the first ball after it was released. The pulse passes unchanged through the internal balls without, therefore, causing movement of these balls. Lack of movement can be affirmed by immobilising one or more of the balls, thereby disproving both the gap and vibrating lattice models. This also contrasts with previous mechanisms that postulate complete energy dispersal within a ball prior to transferring the energy to another ball. Inserting an inelastic barrier between the second and third balls disrupts the pulse such that it spreads out to reach regions that are not in contact with another ball. As a result, the normally stationary third ball is forced into a forward motion, thereby pushing the fourth and fifth ball with it as a single unit. The model is valuable in explaining a fact that has puzzled physicists for generations: why is only one motional mode observed among a multitude of motions that maintain a constant momentum and kinetic energy as required by the laws of physics? The answer lies in the fact that all motions, except the one that is actually observed, require a rebound in one or more of the balls. Since the energy beam formed upon impact is unidirectional, reverse motions are not accommodated.

  11. A virtual source model for Kilo-voltage cone beam CT: Source characteristics and model validation

    International Nuclear Information System (INIS)

    Spezi, E.; Volken, W.; Frei, D.; Fix, M. K.

    2011-01-01

    Purpose: The purpose of this investigation was to study the source characteristics of a clinical kilo-voltage cone beam CT unit and to develop and validate a virtual source model that could be used for treatment planning purposes. Methods: We used a previously commissioned full Monte Carlo model and new bespoke software to study the source characteristics of a clinical kilo-voltage cone beam CT (CBCT) unit. We identified the main particle sources, their spatial, energy and angular distribution for all the image acquisition presets currently used in our clinical practice. This includes a combination of two energies (100 and 120 kVp), two filters (neutral and bowtie), and eight different x-ray beam apertures. We subsequently built a virtual source model which we validated against full Monte Carlo calculations. Results: We found that the radiation output of the clinical kilo-voltage cone beam CT unit investigated in this study could be reproduced with a virtual model comprising of two sources (target and filtration cone) or three sources (target, filtration cone and bowtie filter) when additional filtration was used. With this model, we accounted for more than 97% of the photons exiting the unit. Each source in our model was characterised by a origin distribution in both X and Y directions, a fluence map, a single energy spectrum for unfiltered beams and a two dimensional energy spectrum for bowtie filtered beams. The percentage dose difference between full Monte Carlo and virtual source model based dose distributions was well within the statistical uncertainty associated with the calculations ( ± 2%, one standard deviation) in all cases studied. Conclusions: The virtual source that we developed is accurate in calculating the dose delivered from a commercial kilo-voltage cone beam CT unit operating with routine clinical image acquisition settings. Our data have also shown that target, filtration cone, and bowtie filter sources needed to be all included in the model

  12. Calibration of Eringen's small length scale coefficient for initially stressed vibrating nonlocal Euler beams based on microstructured beam model

    International Nuclear Information System (INIS)

    Wang, C M; Zhang, Z; Challamel, N; Duan, W H

    2013-01-01

    In this paper, we calibrate Eringen's small length scale coefficient e 0 for an initially stressed vibrating nonlocal Euler beam via a microstructured beam modelled by some repetitive cells comprising finite rigid segments and elastic rotational springs. By adopting the pseudo-differential operator and Padé's approximation, an analytical solution for the vibration frequency in terms of initial stress may be developed for the microstructured beam model. When comparing this analytical solution with the established exact vibration solution from the nonlocal beam theory, one finds that the calibrated Eringen's small length scale coefficient e 0 is given by e 0 = √(1/6)-(1/12)(σ 0 /σ-breve m ) where σ 0 is the initial stress and σ-breve m is the mth mode buckling stress of the corresponding local Euler beam. It is shown that e 0 varies with respect to the initial axial stress, from 1/√(12)∼0.289 at the buckling compressive stress to 1/√6∼0.408 when the axial stress is zero and it monotonically increases with increasing initial tensile stress. The small length scale coefficient e 0 , however, does not depend on the vibration/buckling mode considered. (paper)

  13. Modeling sludge accumulation rates in lined pit latrines in slum ...

    African Journals Online (AJOL)

    Modeling sludge accumulation rates in lined pit latrines in slum areas of Kampala City, Uganda. ... African Journal of Environmental Science and Technology ... methods such as open defecation and emptying into storm drainages are employed which consequently contribute to environmental and health-related challenges.

  14. Traceability for Model Driven, Software Product Line Engineering

    NARCIS (Netherlands)

    Anquetil, N.; Grammel, B.; Galvao, I.; Noppen, J.A.R.; Shakil Khan, S.; Arboleda, H.; Rashid, A.; Garcia, A.

    Traceability is an important challenge for software organizations. This is true for traditional software development and even more so in new approaches that introduce more variety of artefacts such as Model Driven development or Software Product Lines. In this paper we look at some aspect of the

  15. Irradiation With Carbon Ion Beams Induces Apoptosis, Autophagy, and Cellular Senescence in a Human Glioma-Derived Cell Line

    International Nuclear Information System (INIS)

    Jinno-Oue, Atsushi; Shimizu, Nobuaki; Hamada, Nobuyuki; Wada, Seiichi; Tanaka, Atsushi; Shinagawa, Masahiko; Ohtsuki, Takahiro; Mori, Takahisa; Saha, Manujendra N.; Hoque, Ariful S.; Islam, Salequl; Kogure, Kimitaka; Funayama, Tomoo; Kobayashi, Yasuhiko

    2010-01-01

    Purpose: We examined biological responses of human glioma cells to irradiation with carbon ion beams (C-ions). Methods and Materials: A human glioma-derived cell line, NP-2, was irradiated with C-ions. Apoptotic cell nuclei were stained with Hoechst 33342. Induction of autophagy was examined either by staining cells with monodansylcadaverine (MDC) or by Western blotting to detect conversion of microtuble-associated protein light chain 3 (MAP-LC3) (LC3-I) to the membrane-bound form (LC3-II). Cellular senescence markers including induction of senescence-associated β-galactosidase (SA-β-gal) were examined. The mean telomere length of irradiated cells was determined by Southern blot hybridization. Expression of tumor suppressor p53 and cyclin/cyclin-dependent kinase inhibitor p21 WAF1/CIP1 in the irradiated cells was analyzed by Western blotting. Results: When NP-2 cells were irradiated with C-ions at 6 Gy, the major population of the cells died of apoptosis and autophagy. The residual fraction of attached cells ( WAF1/CIP1 was induced in NP-2 cells after irradiation. Furthermore, we found that irradiation with C-ions induced cellular senescence in a human glioma cell line lacking functional p53. Conclusions: Irradiation with C-ions induced apoptosis, autophagy, and cellular senescence in human glioma cells.

  16. Numerical Modelling of the Segmental Lining of Underground Structures

    Directory of Open Access Journals (Sweden)

    Akbar Salemi

    2014-12-01

    Full Text Available There are several methods for analysing the behaviour of underground structures under different loading conditions. Most of these methods have many simplifications; therefore, in some cases, the results are too conservative and a very high safety factor, usually of more than 2 is needed. On the other hand, for stability analysis and the designing of support systems, these methods consider segmental lining and its joints as a uniform lining or a lining with pin connections. In this study, numerical modelling of the segmental lining of a tunnel was analysed using a sensitivity analysis of the static modelling. The numerical results were obtained by using a finite difference method (FLAC2D. Using this form of analysis, a new simple methodology was introduced so that more reliable results can be obtained. By comparing the frame analysis results obtained by the SAP2000 software with those obtained by the proposed method, it was concluded that the suggested method can be used as a simple and reasonable approach for the segmental lining of underground structures such as tunnels.

  17. Updating parameters of the chicken processing line model

    DEFF Research Database (Denmark)

    Kurowicka, Dorota; Nauta, Maarten; Jozwiak, Katarzyna

    2010-01-01

    A mathematical model of chicken processing that quantitatively describes the transmission of Campylobacter on chicken carcasses from slaughter to chicken meat product has been developed in Nauta et al. (2005). This model was quantified with expert judgment. Recent availability of data allows...... updating parameters of the model to better describe processes observed in slaughterhouses. We propose Bayesian updating as a suitable technique to update expert judgment with microbiological data. Berrang and Dickens’s data are used to demonstrate performance of this method in updating parameters...... of the chicken processing line model....

  18. Experimental three-dimensional beam profiling and modeling of a terahertz beam generated from a two-color air plasma

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Strikwerda, Andrew; Iwaszczuk, Krzysztof

    2013-01-01

    a sharp, conical intensity profile resembling a donut, and in the focal region the beam collapses to a central, Lorentz-shaped profile. The Lorentzian intensity profile in the focal region can be explained by considering the frequency-dependent spot size derived from measurements of the Gouy phase shift...... in the focal region, and the transition from the donut profile to a central peak is consistent with propagation of a Bessel–Gauss beam, as shown by simulations based on a recent transient photocurrent model (You et al 2012 Phys. Rev. Lett. 109 183902). We combine our measurements to the first full 3D...

  19. An inter-comparison of far-infrared line-by-line radiative transfer models

    International Nuclear Information System (INIS)

    Kratz, D.P.; Mlynczak, M.G.; Mertens, C.J.Christopher J.; Brindley, Helen; Gordley, L.L.; Martin-Torres, Javier; Miskolczi, F.M.; Turner, D.D.

    2005-01-01

    A considerable fraction (>40%) of the outgoing longwave radiation escapes from the Earth's atmosphere-surface system within a region of the spectrum known as the far-infrared (wave-numbers less than 650 cm -1 ). Dominated by the line and continuum spectral features of the pure rotation band of water vapor, the far-infrared has a strong influence upon the radiative balance of the troposphere, and hence upon the climate of the Earth. Despite the importance of the far-infrared contribution, however, very few spectrally resolved observations have been made of the atmosphere for wave-numbers less than 650 cm -1 . The National Aeronautics and Space Administration (NASA), under its Instrument Incubator Program (IIP), is currently developing technology that will enable routine, space-based spectral measurements of the far-infrared. As part of NASA's IIP, the Far-Infrared Spectroscopy of the Troposphere (FIRST) project is developing an instrument that will have the capability of measuring the spectrum over the range from 100 to 1000 cm -1 at a resolution of 0.6 cm -1 . To properly analyze the data from the FIRST instrument, accurate radiative transfer models will be required. Unlike the mid-infrared, however, no inter-comparison of codes has been performed for the far-infrared. Thus, in parallel with the development of the FIRST instrument, an investigation has been undertaken to inter-compare radiative transfer models for potential use in the analysis of far-infrared measurements. The initial phase of this investigation has focused upon the inter-comparison of six distinct line-by-line models. The results from this study have demonstrated remarkably good agreement among the models, with differences being of order 0.5%, thereby providing a high measure of confidence in our ability to accurately compute spectral radiances in the far-infrared

  20. Finite Element Models for Electron Beam Freeform Fabrication Process

    Science.gov (United States)

    Chandra, Umesh

    2012-01-01

    Electron beam freeform fabrication (EBF3) is a member of an emerging class of direct manufacturing processes known as solid freeform fabrication (SFF); another member of the class is the laser deposition process. Successful application of the EBF3 process requires precise control of a number of process parameters such as the EB power, speed, and metal feed rate in order to ensure thermal management; good fusion between the substrate and the first layer and between successive layers; minimize part distortion and residual stresses; and control the microstructure of the finished product. This is the only effort thus far that has addressed computer simulation of the EBF3 process. The models developed in this effort can assist in reducing the number of trials in the laboratory or on the shop floor while making high-quality parts. With some modifications, their use can be further extended to the simulation of laser, TIG (tungsten inert gas), and other deposition processes. A solid mechanics-based finite element code, ABAQUS, was chosen as the primary engine in developing these models whereas a computational fluid dynamics (CFD) code, Fluent, was used in a support role. Several innovative concepts were developed, some of which are highlighted below. These concepts were implemented in a number of new computer models either in the form of stand-alone programs or as user subroutines for ABAQUS and Fluent codes. A database of thermo-physical, mechanical, fluid, and metallurgical properties of stainless steel 304 was developed. Computing models for Gaussian and raster modes of the electron beam heat input were developed. Also, new schemes were devised to account for the heat sink effect during the deposition process. These innovations, and others, lead to improved models for thermal management and prediction of transient/residual stresses and distortions. Two approaches for the prediction of microstructure were pursued. The first was an empirical approach involving the

  1. Self-Consistent Dynamical Model of the Broad Line Region

    International Nuclear Information System (INIS)

    Czerny, Bozena; Li, Yan-Rong; Sredzinska, Justyna; Hryniewicz, Krzysztof; Panda, Swayam; Wildy, Conor; Karas, Vladimir

    2017-01-01

    We develop a self-consistent description of the Broad Line Region based on the concept of a failed wind powered by radiation pressure acting on a dusty accretion disk atmosphere in Keplerian motion. The material raised high above the disk is illuminated, dust evaporates, and the matter falls back toward the disk. This material is the source of emission lines. The model predicts the inner and outer radius of the region, the cloud dynamics under the dust radiation pressure and, subsequently, the gravitational field of the central black hole, which results in asymmetry between the rise and fall. Knowledge of the dynamics allows us to predict the shapes of the emission lines as functions of the basic parameters of an active nucleus: black hole mass, accretion rate, black hole spin (or accretion efficiency) and the viewing angle with respect to the symmetry axis. Here we show preliminary results based on analytical approximations to the cloud motion.

  2. Self-Consistent Dynamical Model of the Broad Line Region

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, Bozena [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Li, Yan-Rong [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing (China); Sredzinska, Justyna; Hryniewicz, Krzysztof [Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Panda, Swayam [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Copernicus Astronomical Center, Polish Academy of Sciences, Warsaw (Poland); Wildy, Conor [Center for Theoretical Physics, Polish Academy of Sciences, Warsaw (Poland); Karas, Vladimir, E-mail: bcz@cft.edu.pl [Astronomical Institute, Czech Academy of Sciences, Prague (Czech Republic)

    2017-06-22

    We develop a self-consistent description of the Broad Line Region based on the concept of a failed wind powered by radiation pressure acting on a dusty accretion disk atmosphere in Keplerian motion. The material raised high above the disk is illuminated, dust evaporates, and the matter falls back toward the disk. This material is the source of emission lines. The model predicts the inner and outer radius of the region, the cloud dynamics under the dust radiation pressure and, subsequently, the gravitational field of the central black hole, which results in asymmetry between the rise and fall. Knowledge of the dynamics allows us to predict the shapes of the emission lines as functions of the basic parameters of an active nucleus: black hole mass, accretion rate, black hole spin (or accretion efficiency) and the viewing angle with respect to the symmetry axis. Here we show preliminary results based on analytical approximations to the cloud motion.

  3. Modelling the line-of-sight contribution in substructure lensing

    Science.gov (United States)

    Despali, Giulia; Vegetti, Simona; White, Simon D. M.; Giocoli, Carlo; van den Bosch, Frank C.

    2018-04-01

    We investigate how Einstein rings and magnified arcs are affected by small-mass dark-matter haloes placed along the line of sight to gravitational lens systems. By comparing the gravitational signature of line-of-sight haloes with that of substructures within the lensing galaxy, we derive a mass-redshift relation that allows us to rescale the detection threshold (i.e. lowest detectable mass) for substructures to a detection threshold for line-of-sight haloes at any redshift. We then quantify the line-of-sight contribution to the total number density of low-mass objects that can be detected through strong gravitational lensing. Finally, we assess the degeneracy between substructures and line-of-sight haloes of different mass and redshift to provide a statistical interpretation of current and future detections, with the aim of distinguishing between cold dark matter and warm dark matter. We find that line-of-sight haloes statistically dominate with respect to substructures, by an amount that strongly depends on the source and lens redshifts, and on the chosen dark-matter model. Substructures represent about 30 percent of the total number of perturbers for low lens and source redshifts (as for the SLACS lenses), but less than 10 per cent for high-redshift systems. We also find that for data with high enough signal-to-noise ratio and angular resolution, the non-linear effects arising from a double-lens-plane configuration are such that one is able to observationally recover the line-of-sight halo redshift with an absolute error precision of 0.15 at the 68 per cent confidence level.

  4. Calibrating and validating a FE model for long-term behavior of RC beams

    Directory of Open Access Journals (Sweden)

    Tošić Nikola D.

    2014-01-01

    Full Text Available This study presents the research carried out in finding an optimal finite element (FE model for calculating the long-term behavior of reinforced concrete (RC beams. A multi-purpose finite element software DIANA was used. A benchmark test in the form of a simply supported beam loaded in four point bending was selected for model calibration. The result was the choice of 3-node beam elements, a multi-directional fixed crack model with constant stress cut-off, nonlinear tension softening and constant shear retention and a creep and shrinkage model according to CEB-FIP Model Code 1990. The model was then validated on 14 simply supported beams and 6 continuous beams. Good agreement was found with experimental results (within ±15%.

  5. Modelling and Testing of the Piezoelectric Beam as Energy Harvesting System

    Directory of Open Access Journals (Sweden)

    Koszewnik Andrzej

    2016-12-01

    Full Text Available The paper describes modelling and testing of the piezoelectric beam as energy harvesting system. The cantilever beam with two piezo-elements glued onto its surface is considered in the paper. As result of carried out modal analysis of the beam the natural frequencies and modes shapes are determined. The obtained results in the way mentioned above allow to estimate such location of the piezo-actuator on the beam where the piezo generates maximal values of modal control forces. Experimental investigations carried out in the laboratory allow to verify results of natural frequencies obtained during simulation and also testing of the beam in order to obtain voltage from vibration with help of the piezo-harvester. The obtained values of voltage stored on the capacitor C0 shown that the best results are achieved for the beam excited to vibration with third natural frequency, but the worst results for the beam oscillating with the first natural frequency.

  6. Statistical properties of a Laguerre-Gaussian Schell-model beam in turbulent atmosphere.

    Science.gov (United States)

    Chen, Rong; Liu, Lin; Zhu, Shijun; Wu, Gaofeng; Wang, Fei; Cai, Yangjian

    2014-01-27

    Laguerre-Gaussian Schell-model (LGSM) beam was proposed in theory [Opt. Lett.38, 91 (2013 Opt. Lett.38, 1814 (2013)] just recently. In this paper, we study the propagation of a LGSM beam in turbulent atmosphere. Analytical expressions for the cross-spectral density and the second-order moments of the Wigner distribution function of a LGSM beam in turbulent atmosphere are derived. The statistical properties, such as the degree of coherence and the propagation factor, of a LGSM beam in turbulent atmosphere are studied in detail. It is found that a LGSM beam with larger mode order n is less affected by turbulence than a LGSM beam with smaller mode order n or a GSM beam under certain condition, which will be useful in free-space optical communications.

  7. Numerical model of RC beam response to corrosion

    Science.gov (United States)

    German, Magdalena; Pamin, Jerzy

    2018-01-01

    The chloride-induced corrosion of reinforcement used to be represented by Tuutti's model with initiation and propagation phases. During the initiation phase chlorides penetrate the concrete cover and accumulate around reinforcement bars. The chloride concentration in concrete increases until it reaches a chloride threshold value, causing deterioration of the passive layer of reinforcement. Then the propagation phase begins. During the propagation phase steel has no natural anti-corrosion protection, a corrosion current flows and this induces the production of rust. A growing volume of corrosion products generates stresses in concrete, which leads to cracking, splitting, delamination and loss of strength. The mechanical response of RC elements to reinforcement corrosion has mostly been examined on the basis of a 2D cross-section analysis. However, with this approach it is not possible to represent both corrosion and static loading. In the paper a 3D finite element model of an RC beam with the two actions applied is presented. Rust is represented as an interface between steel and concrete, considering the volumetric expansion of rust.

  8. Electron beam lithographic modeling assisted by artificial intelligence technology

    Science.gov (United States)

    Nakayamada, Noriaki; Nishimura, Rieko; Miura, Satoru; Nomura, Haruyuki; Kamikubo, Takashi

    2017-07-01

    We propose a new concept of tuning a point-spread function (a "kernel" function) in the modeling of electron beam lithography using the machine learning scheme. Normally in the work of artificial intelligence, the researchers focus on the output results from a neural network, such as success ratio in image recognition or improved production yield, etc. In this work, we put more focus on the weights connecting the nodes in a convolutional neural network, which are naturally the fractions of a point-spread function, and take out those weighted fractions after learning to be utilized as a tuned kernel. Proof-of-concept of the kernel tuning has been demonstrated using the examples of proximity effect correction with 2-layer network, and charging effect correction with 3-layer network. This type of new tuning method can be beneficial to give researchers more insights to come up with a better model, yet it might be too early to be deployed to production to give better critical dimension (CD) and positional accuracy almost instantly.

  9. 3D measurement for archeological artifact using CCD camera and line laser beam

    Science.gov (United States)

    Yokoyama, Hiroshi; Hatano, Katsuhiro; Chikatsu, Hirofumi

    1997-07-01

    In the compilation of archival records for archeological artifacts, true ortho-graphic drawings of these artifacts have to be drawn by the archaeologists themselves or part- timers, taking a great deal of time, labor and skill. For saving the labor, the authors have developed ortho projection system using CCD camera. 3D measurement system using ortho projection system are described in this paper. Finally, it demonstrates wireframe model for jomon-pottery by using this system.

  10. Study on Tower Models for EHV Transmission Line

    Directory of Open Access Journals (Sweden)

    Xu Bao-Qing

    2016-01-01

    Full Text Available Lightning outage accident is one of the main factors that threat seriously the safe and reliable operation of power system. So it is very important to establish reasonable transmission tower model and evaluate the impulse response characteristic of lightning wave traveling on the transmission tower properly for determining reliable lightning protection performance. With the help of Electromagnetic Transient Program (EMTP, six 500kV tower models are built. Aiming at one line to one transformer operating mode of 500kV substation, the intruding wave overvoltage under different tower models is calculated. The effect of tower model on intruding overvoltage has been studied. The results show that different tower models can result in great differences to the calculation results. Hence, reasonable selection of the tower model in the calculation of back- strike intruding wave is very important.

  11. A modelling approach for railway overhead line equipment asset management

    OpenAIRE

    Kilsby, Paul; Remenyte-Prescott, Rasa; Andrews, John

    2017-01-01

    The Overhead Line Equipment (OLE) is a critical sub-system of the 25kV AC overhead railway electrification system. If OLE asset management strategies can be evaluated using a whole lifecycle cost analysis that considers degradation processes and maintenance activities of the OLE components, the investment required to deliver the level of performance desired by railway customers and regulators can be based on evidence from the analysis results. A High Level Petri Net (HLPN) model, proposed in ...

  12. Modeling the Structural Response of Reinforced Glass Beams using an SLA Scheme

    NARCIS (Netherlands)

    Louter, P.C.; Graaf, van de Anne; Rots, J.G.; Bos, Freek; Louter, Pieter Christiaan; Veer, Fred

    2010-01-01

    This paper investigates whether a novel computational sequentially linear analysis (SLA) technique, which is especially developed for modeling brittle material response, is applicable for modeling the structural response of metal reinforced glass beams. To do so, computational SLA results are

  13. A TCP model for external beam treatment of intermediate-risk prostate cancer.

    LENUS (Irish Health Repository)

    Walsh, Seán

    2013-03-01

    Biological models offer the ability to predict clinical outcomes. The authors describe a model to predict the clinical response of intermediate-risk prostate cancer to external beam radiotherapy for a variety of fractionation regimes.

  14. Bio-physical effects of scanned proton beams: measurements and models for discrete high dose rates scanning systems

    International Nuclear Information System (INIS)

    De-Marzi, Ludovic

    2016-01-01

    The main objective of this thesis is to develop and optimize algorithms for intensity modulated proton therapy, taking into account the physical and biological pencil beam properties. A model based on the summation and fluence weighted division of the pencil beams has been used. A new parameterization of the lateral dose distribution has been developed using a combination of three Gaussian functions. The algorithms have been implemented into a treatment planning system, then experimentally validated and compared with Monte Carlo simulations. Some approximations have been made and validated in order to achieve reasonable calculation times for clinical purposes. In a second phase, a collaboration with Institut Curie radiobiological teams has been started in order to implement radiobiological parameters and results into the optimization loop of the treatment planning process. Indeed, scanned pencil beams are pulsed and delivered at high dose rates (from 10 to 100 Gy/s), and the relative biological efficiency of protons is still relatively unknown given the wide diversity of use of these beams: the different models available and their dependence with linear energy transfers have been studied. A good agreement between dose calculations and measurements (deviations lower than 3 % and 2 mm) has been obtained. An experimental protocol has been set in order to qualify pulsed high dose rate effects and preliminary results obtained on one cell line suggested variations of the biological efficiency up to 10 %, though with large uncertainties. (author) [fr

  15. Development of EPICS based beam-line experimental control employing motor controller for precision positioning

    International Nuclear Information System (INIS)

    Tuli, Anupriya; Jain, Rajiv; Vora, H.S.

    2015-01-01

    In a Synchrotron Radiation Source the beamline experiments are carried out in radiation prone environment, inside the hutch, which demands to conduct experiments remotely. These experiments involves instrument control and data acquisition from various devices. Another factor which attributes to system complexity is precise positioning of sample and placement of detectors. A large number of stepper motors are engaged for achieving the required precision positioning. This work is a result of development of Experimental Physics and Industrial Control System (EPICS) based control system to interface a stepper motor controller developed indigenously by Laser Electronics Support Division of RRCAT. EPICS is an internationally accepted open source software environment which follows toolkit approach and standard model paradigm. The operator interface for the control system software was implemented using CSS BOY. The system was successfully tested for Ethernet based remote access. The developed control software comprises of an OPI and alarm handler (EPICS ALH). Both OPI and ALH are linked with PV's defined in database files. The development process resulted into a set of EPICS based commands for controlling stepper motor. These commands are independent of operator interface, i.e. stepper motor can be controlled by using these set of commands directly on EPICS prompt. This command set is illustrated in the above table. EPICS Alarm Handler was also tested independently by running these commands on EPIC prompt. If not using ALH, operator can read the alarm status of a PV using 'SEVR' and 'STAT' attributes. (author)

  16. A method of determining acoustical physical constants for piezoelectric materials by line-focus-beam acoustic microscopy.

    Science.gov (United States)

    Takanaga, Izumi; Kushibiki, Jun-ichi

    2002-07-01

    We developed a new method of determining acoustical physical constants (elastic constant, piezoelectric constant, dielectric constant, and density) of piezoelectric materials with high accuracy. This method acquires velocities of leaky surface acoustic waves (LSAWs) excited on the water-loaded specimen surface, measured by line-focus-beam (LFB) acoustic microscopy, and bulk velocities of longitudinal and shear waves, measured with plane-wave transducers replacing the LFB device in the same system, together with the dielectric constants and density measured independently, for a small number of specimens. For LiNbO3 and LiTaO3 crystals, we demonstrated that we could accurately determine the constants by choosing proper propagation directions of LSAWs and bulk waves for three principal X-, Y-, and Z-cut specimens and one rotated Y-cut specimen [(104) plate for LiNbO3 and (012) plate for LiTaOa]. The accuracy is nearly the same as that for the constants determined only from the bulk wave velocities.

  17. Extending the Nonlinear-Beam-Dynamics Concept of 1D Fixed Points to 2D Fixed Lines

    CERN Document Server

    Franchetti, G.

    2015-01-01

    The origin of nonlinear dynamics traces back to the study of the dynamics of planets with the seminal work of Poincaré at the end of the nineteenth century: Les Méthodes Nouvelles de la Mécanique Céleste, Vols. 1–3 (Gauthier Villars, Paris, 1899). In his work he introduced a methodology fruitful for investigating the dynamical properties of complex systems, which led to the so-called “Poincaré surface of section,” which allows one to capture the global dynamical properties of a system, characterized by fixed points and separatrices with respect to regular and chaotic motion. For two-dimensional phase space (one degree of freedom) this approach has been extremely useful and applied to particle accelerators for controlling their beam dynamics as of the second half of the twentieth century.We describe here an extension of the concept of 1D fixed points to fixed lines in two dimensions. These structures become the fundamental entities for characterizing the nonlinear motion in the four-dimensional phas...

  18. Focused beam reflectance method as an innovative (PAT) tool to monitor in-line granulation process in fluidized bed.

    Science.gov (United States)

    Alshihabi, Firas; Vandamme, Thierry; Betz, Gabriele

    2013-02-01

    Fluidized bed granulation is a commonly used unit operation in the pharmaceutical industry. But still to obtain and control the desired granule size is challenging due to many process variables affecting the final product. Focused beam reflectance measurement (FBRM, Mettler-Toledo, Switzerland) is an increasingly popular particle growth analysis technique. FBRM tool was installed in two different locations inside a fluidized bed granulator (GPCG2, Glatt, Binzen) in order to monitor the granulation growth kinetics. An experimental design was created to study the effect of process variables using FBRM probe and comparing the results with the one's measured by sieve analysis. The probe location is of major importance to get smooth and robust curves. The excess feeding of binder solution might lead to agglomeration and thus to process collapse, however this phenomenon was clearly detected with FBRM method. On the other hand, the process variables at certain levels might affect the FBRM efficiency by blocking the probe window with sticky particles. A good correlation was obtained (R(2) = 0.95) between FBRM and sieve analysis mean particle size. The proposed in-line monitoring tool enables the operator to select appropriate process parameters and control the wet granulation process more efficiently.

  19. Study of different registration methods for on-line kilovoltage cone-beam CT guided lung cancer radiation

    International Nuclear Information System (INIS)

    Wang Yanyang; Fu Xiaolong; Xia Bing; Wu Zhengqin; Fan Min; Yang Huanjun; Xu Zhiyong; Jiang Guoliang

    2009-01-01

    Objective: To select the optimal registration method for on-line kilovoltage cone-beam CT (KVCBCT) guided lung cancer radiation and evaluate the reproducibility of the selected method. Methods: Sixteen patients with non-small cell lung cancer were enrolled into this study. A total of 96 pretreatment KVCBCT images from the 16 patients were available for the analysis. Image registration methods were bone-based automatic registration, gray-based automatic registration, manual registration and semi-automatic registration. All registrations were accomplished by one physician. Another physician blindly evaluated the results of each registration, then selected the optimal registration method and evaluated its reproducibility. Results: The average score of the bone-based automatic registration, gray-based automatic registration, manual registration and semi-automatic registration methods was 2.4, 2.7, 3.0 and 3.7, respectively. The score of the four different groups had statistics significant difference (F=42.20, P<0.001). Using the semi-automatic registration method, the probability of the difference between two registration results more than 3 mm in the left-right, superior-inferior, and anterior-posterior directions was 0, 3% and 6% by the same physician, 0, 14% and 0 by different physicians, and 8%, 14% and 8% by physician and radiation therapist. Conclusions: Semi-automatic registration method, possessing the highest score and accepted reproducibility, is appropriate for KVCBCT guided lung cancer radiation. (authors)

  20. Beam heating studies on an early model is a superconducting cosine theta magnet

    International Nuclear Information System (INIS)

    Bozoki, G.; Bunce, G.; Danby, G.; Foelsche, H.; Jackson, J.; Prodell, A.; Soukas, A.; Stevens, A.; Stoehr, R.; Weisenbloom, J.

    1980-01-01

    Superconducting magnets for accelerators can be accidentally quenched by heat resulting from beam losses in the magnet. The threshold for such quenches is determined by the time structure of the beam loss and by details of the magnet application, construction and cooling. A 4.25 m long superconducting cosine theta dipole magnet, MARK VI, constructed during the research and development phase of the ISABELLE Project at BNL was installed in the 28.5 GeV/c primary proton beam line from the AGS. By energizing the magnet, the proton beam could be deflected into the magnet. The beam intensity required to quench the magnet was observed for different beam sizes and at several values of magnet current up to 2400 A or approximately 70% of the highest magnet operating current. The maximum current was limited by the gas-cooled power lead flow available using pool-boiling helium rather than single phase forced-flow helium at 5 atm for which the magnet system was designed. Details of the experimental setup including the magnet and cryogenic system, the beam-monitoring equipment and instrumentation are described. The measurements are discussed and compared with beam heating measurements made on another superconducting magnet and interpreted using the Cascade Simulation Program, CASIM

  1. Wakefield and the diffraction model due to a flat beam moving past a conducting wedge

    International Nuclear Information System (INIS)

    Chao, A.W.; Henke, H.

    1995-07-01

    A collimator is often used to clean a beam of its excessive tail particles. If the beam intensity is high enough or if the beam is brought too close to the collimator, however, the wakefields generated by the beam-collimator interaction can cause additional beam tails to grow, thus defeating, or even worsening, the beam-tail cleaning process. The wakefield generated by a sheet beam moving past a conducting wedge has been obtained in closed form by Henke using the method of conformal mapping. This result is applied in the present work to obtain the wake force and the transverse kick received by a test charge moving with the beam. For the beam to be approximated as sheet beams, it is assumed to be flat and the collimator is assumed to have an infinite extent in the flat dimention. We derive an exact expression for the transverse wake force delivered to particles in the beam bunch. Implication of emittance growth as a beam passes closely by a collimator is discussed. We consider two idealized wedge geometries: In Section 2, when the wedge has the geometry as a disrupted beam pipe, and in Section 3, when it is like a semi-infinite screen. Unfortunately, we do not have solutions for more realistic collimator geometries such as when it is tapered to minimize the wakefield effects. However, our results should still serve as pessimistic limiting cases. An interesting opportunity is offered by our exact calculation of the wakefields: it can be used to confront the diffraction model used to estimate the high-frequency impedance of a cavity structure. It is shown that the field pattern, as well as the impedance, agrees with those obtained by the diffraction model in appropriate limits

  2. Parametric Study of the current limit within a single driver-scale transport beam line of an induction Linac for Heavy Ion Fusion

    International Nuclear Information System (INIS)

    Prost, Lionel Robert

    2007-01-01

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density ∼0.2 (micro)C/m) over long pulse durations (4 (micro)s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K + ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor (∼80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics

  3. Parametic Study of the current limit within a single driver-scaletransport beam line of an induction Linac for Heavy Ion Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Prost, Lionel Robert [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density ~0.2 μC/m) over long pulse durations (4 μs) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K+ ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor (~80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  4. Modeling and computer simulation of ion beam synthesis of nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, M.

    1999-11-01

    The following topics were dealt with: ion beam synthesis of nanoclusters, kinetic three dimensional lattice Monte Carlo method, Ostwald ripening, redistribution of implanted impurities, buried layer formation, comparisation to experimental results.

  5. Analysis of the influence of foundation beams on displacements and bearing capacity of horizontally loaded supports of power lines and contact systems basing on theoretical and experimental data

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2016-10-01

    Full Text Available The issues of bearing structures reliability for energy lines are of special importance in case of the use of single post horizontally loaded pile foundations of power lines and contact system supports. The required level of operational reliability of single post horizontally loaded supports in case of variability of strain-strength features of foundation soils along the route may be provided by using optimal sizes and number of foundation beams creating additional reactive impedance of soil to the loaded support. Foundation beams laid in soil perpendicular to a horizontally loaded support for increasing its bearing capacity are rather widely used. Though the issues of technical and economic substantiation of the choice of optimal sizes and number of beams influencing the strain and bearing capacity of power lines and contact system supports haven’t been studied enough. Basing on the experimental and theoretical studies the authors proposes his assessment of technical and economical efficiency of the use of foundation beams depending on their geometrical parameters, the amount and height of horizontal loading on a support.

  6. Developing models for simulation of pinched-beam dynamics in heavy ion fusion

    International Nuclear Information System (INIS)

    Boyd, J.K.; Mark, J.W.K.; Sharp, W.M.; Yu, S.S.

    1984-01-01

    Hydrodynamic models have been derived by Mark and Yu and by others to describe energetic pinched-beams, such as those used in ion-beam fusion. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. The other models treated here use an ideal gas closure and a closure by Newcomb based on an expansion in V/sub th//V/sub z/. Features of these hydrodynamic beam models are compared with a kinetic treatment

  7. A new model for 'accept or reject' strategies in off-line and on-line megavoltage treatment evaluation

    International Nuclear Information System (INIS)

    Yan Di; Wong, John W.; Gustafson, Gary; Martinez, Alvaro

    1995-01-01

    Purpose: With megavoltage on-line imaging, a temporal record of the treatment setup variation is made available during the course of radiotherapy. This work describes the theoretical framework where the imaging data is incorporated as feedback for deriving off-line and on-line 'accept or reject' decisions to improve the quality of radiotherapy on an individual patient basis. Methods and Materials: A dynamic model of treatment setup variation is developed to describe: (a) the variations of multifraction treatment position and (b) the variation of measurement. Based on this model, a confidence region of subsequent treatment position is estimated from measurements of previous treatment position. The confidence region is compared with an allowance region of the treatment position, representing the acceptable margin of setup variation. The difference of the two regions are then evaluated to derive off-line and on-line 'accept or reject' treatment decisions. Results: The model was simulated retrospectively using sequential daily images from different treatment sites. 'Accept or reject' decisions were produced for on-line and off-line applications. The results also demonstrate the ability of the model to include the effects of setup variation that drifted during the course of treatment. Conclusion: The preliminary result demonstrates that 'accept or reject' treatment decisions can be derived quantitatively from on-line imaging data. The model shows potential to guide the physician and therapist in implementing efficient and accurate treatment adjustments. Further work is required to test the model in the clinical setting

  8. Measurements of radiation near an atomic spectral line from the interaction of a 30 GeV electron beam and a long plasma

    International Nuclear Information System (INIS)

    Catravas, P.E.; Chattopadhyay, S.; Esarey, E.; Leemans, W.P.; Assmann, R.; Decker, F.-J.; Hogan, M.J.; Iverson, R.; Siemann, R.H.; Walz, D.; Whittum, D.; Blue, B.; Clayton, C; Joshi, C.; Marsh, K.A.; Mori, W.B.; Wang, S.; Katsouleas, T.; Lee, S.; Muggli, P.

    2000-01-01

    Emissions produced or initiated by a 30 GeV electron beam propagating through a ∼ 1 m long heat pipe oven containing neutral and partially ionized vapor have been measured near atomic spectral lines in a beam-plasma wakefield experiment. The Cerenkov spatial profile has been studied as a function of oven temperature and pressure, observation wavelength, and ionizing laser intensity and delay. The Cerenkov peak angle is affected by the creating of plasma, and estimates of neutral and plasma density have been extracted. Increases in visible background radiation, consistent with increased plasma recombination emissions due to dissipation of wakefields, were simultaneously measured

  9. Measured and simulated transport of 1.9 MeV laser-accelerated proton bunches through an integrated test beam line at 1 Hz

    OpenAIRE

    M. Nishiuchi; H. Sakaki; T. Hori; P. R. Bolton; K. Ogura; A. Sagisaka; A. Yogo; M. Mori; S. Orimo; A. S. Pirozhkov; I. Daito; H. Kiriyama; H. Okada; S. Kanazawa; S. Kondo

    2010-01-01

    A laser-driven repetition-rated 1.9 MeV proton beam line composed of permanent quadrupole magnets (PMQs), a radio frequency (rf) phase rotation cavity, and a tunable monochromator is developed to evaluate and to test the simulation of laser-accelerated proton beam transport through an integrated system for the first time. In addition, the proton spectral modulation and focusing behavior of the rf phase rotation cavity device is monitored with input from a PMQ triplet. In the 1.9 MeV region we...

  10. A Compliant Bistable Mechanism Design Incorporating Elastica Buckling Beam Theory and Pseudo-Rigid-Body Model

    DEFF Research Database (Denmark)

    Sönmez, Ümit; Tutum, Cem Celal

    2008-01-01

    In this work, a new compliant bistable mechanism design is introduced. The combined use of pseudo-rigid-body model (PRBM) and the Elastica buckling theory is presented for the first time to analyze the new design. This mechanism consists of the large deflecting straight beams, buckling beams......, and a slider. The kinematic analysis of this new mechanism is studied, using nonlinear Elastica buckling beam theory, the PRBM of a large deflecting cantilever beam, the vector loop closure equations, and numerically solving nonlinear algebraic equations. A design method of the bistable mechanism...

  11. Dynamic Analysis of Thick Plates Including Deep Beams on Elastic Foundations Using Modified Vlasov Model

    Directory of Open Access Journals (Sweden)

    Korhan Ozgan

    2013-01-01

    Full Text Available Dynamic analysis of foundation plate-beam systems with transverse shear deformation is presented using modified Vlasov foundation model. Finite element formulation of the problem is derived by using an 8-node (PBQ8 finite element based on Mindlin plate theory for the plate and a 2-node Hughes element based on Timoshenko beam theory for the beam. Selective reduced integration technique is used to avoid shear locking problem for the evaluation of the stiffness matrices for both the elements. The effect of beam thickness, the aspect ratio of the plate and subsoil depth on the response of plate-beam-soil system is analyzed. Numerical examples show that the displacement, bending moments and shear forces are changed significantly by adding the beams.

  12. Extension of non-linear beam models with deformable cross sections

    Science.gov (United States)

    Sokolov, I.; Krylov, S.; Harari, I.

    2015-12-01

    Geometrically exact beam theory is extended to allow distortion of the cross section. We present an appropriate set of cross-section basis functions and provide physical insight to the cross-sectional distortion from linear elastostatics. The beam formulation in terms of material (back-rotated) beam internal force resultants and work-conjugate kinematic quantities emerges naturally from the material description of virtual work of constrained finite elasticity. The inclusion of cross-sectional deformation allows straightforward application of three-dimensional constitutive laws in the beam formulation. Beam counterparts of applied loads are expressed in terms of the original three-dimensional data. Special attention is paid to the treatment of the applied stress, keeping in mind applications such as hydrogel actuators under environmental stimuli or devices made of electroactive polymers. Numerical comparisons show the ability of the beam model to reproduce finite elasticity results with good efficiency.

  13. Modelling and calibration of the laser beam-scanning triangulation measurement system

    NARCIS (Netherlands)

    Wang, G.Y.; Zheng, Bing; Li, Xin; Houkes, Z.; Regtien, Paulus P.L.

    2002-01-01

    We present an approach of modelling and calibration of an active laser beam-scanning triangulation measurement system. The system works with the pattern of two-dimensional beam-scanning illumination and one-dimensional slit-scanning detection with a photo-multiplier tube instead of a CCD camera. By

  14. Modelling the spatial shape of nondiffracting beams: Experimental generation of Frozen Waves via computer generated holograms

    OpenAIRE

    Vieira, Tárcio A.; Zamboni-Rached, Michel; Gesualdi, Marcos R. R.

    2013-01-01

    In this paper we implement experimentally the spatial shape modelling of nondiffracting optical beams via computer generated holograms. The results reported here are the experimental confirmation of the so called Frozen Wave method, developed few years ago. Optical beams of this type can possess potential applications in optical tweezers, medicine, atom guiding, remote sensing, etc..

  15. Hybrid neural network model for the design of beam subjected to ...

    Indian Academy of Sciences (India)

    Design of beam; hybridization; genetic algorithms; neural networks. ... A hybrid neural network model which combines the features of feed forward neural networks and genetic algorithms has been developed for the design of beam ... Department of Civil Engineering, J.N.T.U College of Engineering, Anantapur 515 002 ...

  16. Efficient material flow in mixed model assembly lines.

    Science.gov (United States)

    Alnahhal, Mohammed; Noche, Bernd

    2013-01-01

    In this study, material flow from decentralized supermarkets to stations in mixed model assembly lines using tow (tugger) trains is investigated. Train routing, scheduling, and loading problems are investigated in parallel to minimize the number of trains, variability in loading and in routes lengths, and line-side inventory holding costs. The general framework for solving these problems in parallel contains analytical equations, Dynamic Programming (DP), and Mixed Integer Programming (MIP). Matlab in conjunction with LP-solve software was used to formulate the problem. An example was presented to explain the idea. Results which were obtained in very short CPU time showed the effect of using time buffer among routes on the feasible space and on the optimal solution. Results also showed the effect of the objective, concerning reducing the variability in loading, on the results of routing, scheduling, and loading. Moreover, results showed the importance of considering the maximum line-side inventory beside the capacity of the train in the same time in finding the optimal solution.

  17. Development of apparatus for high-intensity beam lines at the KEK-PS new experimental hall

    International Nuclear Information System (INIS)

    Yamanoi, Yutaka; Tanaka, Kazuhiro; Minakawa, Michifumi

    1992-01-01

    The new counter experimental hall was constructed at the KEK 12 GeV Proton Synchrotron (the KEK-PS) in order to handle high-intensity primary proton beams of up to 1 x 10 13 pps (protons per second), which is one order of magnitude greater than the present beam intensity of the KEK-PS, 1 x 10 12 pps. New technologies for handling high-intensity beams have, then, been developed and employed in the new hall construction. A part of our R/D work on handling high intensity beam is briefly reported. (author)

  18. Twisted sigma-model solitons on the quantum projective line

    Science.gov (United States)

    Landi, Giovanni

    2018-04-01

    On the configuration space of projections in a noncommutative algebra, and for an automorphism of the algebra, we use a twisted Hochschild cocycle for an action functional and a twisted cyclic cocycle for a topological term. The latter is Hochschild-cohomologous to the former and positivity in twisted Hochschild cohomology results into a lower bound for the action functional. While the equations for the critical points are rather involved, the use of the positivity and the bound by the topological term lead to self-duality equations (thus yielding twisted noncommutative sigma-model solitons, or instantons). We present explicit nontrivial solutions on the quantum projective line.

  19. Prescribed wind shear modelling with the actuator line technique

    DEFF Research Database (Denmark)

    Mikkelsen, Robert Flemming; Sørensen, Jens Nørkær; Troldborg, Niels

    2007-01-01

    A method for prescribing arbitrary steady atmospheric wind shear profiles combined with CFD is presented. The method is furthermore combined with the actuator line technique governing the aerodynamic loads on a wind turbine. Computation are carried out on a wind turbine exposed to a representative...... steady atmospheric wind shear profile with and without wind direction changes up through the atmospheric boundary layer. Results show that the main impact on the turbine is captured by the model. Analysis of the wake behind the wind turbine, reveal the formation of a skewed wake geometry interacting...

  20. The Eurisol report. A feasibility study for a European isotope-separation-on-line radioactive ion beam facility

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-01

    The Eurisol project aims at a preliminary design study of the next-generation European isotope separation on-line (ISOL) radioactive ion beam (RIB) facility. In this document, the scientific case of high-intensity RIBs using the ISOL method is first summarised, more details being given in appendix A. It includes: 1) the study of atomic nuclei under extreme and so-far unexplored conditions of composition (i.e. as a function of the numbers of protons and neutrons, or the so-called isospin), rotational angular velocity (or spin), density and temperature, 2) the investigation of the nucleosynthesis of heavy elements in the Universe, an important part of nuclear astrophysics, 3) a study of the properties of the fundamental interactions which govern the properties of the universe, and in particular of the violation of some of their symmetries, 4) potential applications of RIBs in solid-state physics and in nuclear medicine, for example, where completely new fields could be opened up by the availability of high-intensity RIBs produced by the ISOL method. The proposed Eurisol facility is then presented, with particular emphasis on its main components: the driver accelerator, the target/ion-source assembly, the mass-selection system and post-accelerator, and the required scientific instrumentation. Special details of these components are given in appendices B to E, respectively. The estimates of the costs of the Eurisol, construction and running costs, have been performed in as much details as is presently possible. The total capital cost (installation manpower cost included) of the project is estimated to be of the order of 630 million Euros within 20%. In general, experience has shown that operational costs per annum for large accelerator facilities are about 10% of the capital cost. (A.C.)

  1. Model of emittance growth in a self-pinched beam

    International Nuclear Information System (INIS)

    Lee, E.P.; Yu, S.S.

    1979-01-01

    A semi-phenomenological formula is proposed for the change of emittance of a self-pinched beam which is not matched to its equilibrium radius. Near equilibrium this formula, coupled with an envelope equation, yields the damped sausage oscillations observed in simulation and experiments. For a beam which is injected cold (no transverse velocity spread), the formula coincides with the analytically calculated initial growth of emittance. The basic theory is developed here and used to compute the linear damping rate for several current profiles. The resultant non-linear increase in equilibrium quantities is also calculated in lowest order of the degree of mismatch

  2. Modeling the interaction of high power ion or electron beams with solid target materials

    International Nuclear Information System (INIS)

    Hassanein, A.M.

    1983-11-01

    Intense energy deposition on first wall materials and other components as a result of plasma disruptions in magnetic fusion devices are expected to cause melting and vaporization of these materials. The exact amount of vaporization losses and melt layer thickness are very important to fusion reactor design and lifetime. Experiments using ion or electron beams to simulate the disruption effects have different environments than the actual disruption conditions in fusion reactors. A model has been developed to accurately simulate the beam-target interactions so that the results from such experiments can be meaningful and useful to reactor design. This model includes a two dimensional solution of the heat conduction equation with moving boundaries. It is found that the vaporization and melting of the sample strongly depends on the characteristics of the beam spatial distribution, beam diameter, and on the power-time variation of the beam

  3. Dipole saturated absorption modeling in gas phase: Dealing with a Gaussian beam

    Science.gov (United States)

    Dupré, Patrick

    2018-01-01

    With the advent of new accurate and sensitive spectrometers, cf. combining optical cavities (for absorption enhancement), the requirement for reliable molecular transition modeling is becoming more pressing. Unfortunately, there is no trivial approach which can provide a definitive formalism allowing us to solve the coupled systems of equations associated with nonlinear absorption. Here, we propose a general approach to deal with any spectral shape of the electromagnetic field interacting with a molecular species under saturation conditions. The development is specifically applied to Gaussian-shaped beams. To make the analytical expressions tractable, approximations are proposed. Finally, two or three numerical integrations are required for describing the Lamb-dip profile. The implemented model allows us to describe the saturated absorption under low pressure conditions where the broadening by the transit-time may dominate the collision rates. The model is applied to two specific overtone transitions of the molecular acetylene. The simulated line shapes are discussed versus the collision and the transit-time rates. The specific collisional and collision-free regimes are illustrated, while the Rabi frequency controls the intermediate regime. We illustrate how to recover the input parameters by fitting the simulated profiles.

  4. A Novel Analytical Model to Design Piezoelectric Patches Used to Repair Cracked Beams

    Directory of Open Access Journals (Sweden)

    Waleed Al-Ashtari

    2016-06-01

    Full Text Available In this paper, an analytical solution describing the deflection of a cracked beam repaired with piezoelectric patch is introduced. The solution is derived using perturbation method. A novel analytical model to calculate the proper dimensions of piezoelectric patches used to repair cracked beams is also introduced. This model shows that the thickness of the piezoelectric patch depends mainly on the thickness of the cracked beam, the electro-mechanical properties of the patch material, the applied load and the crack location. Furthermore, the model shows that the length of the piezoelectric patches depends on the thickness of the patch as well as it depends on the length of the cracked beam and the crack depth. The additional flexibility of the beam caused by crack is modeled depending on a dimensionless parameter identified from finite elements method. Different piezoelectric patches were designed and investigated using analytical and finite elements models. The results show that increasing the patch thickness enhances the beam resistance to crack and load effects, while increasing the length of the piezoelectric patch reduces the magnitude of the voltage required to repair the cracked beam.

  5. Modeling and simulations of new electrostatically driven, bimorph actuator for high beam steering micromirror deflection angles

    Science.gov (United States)

    Walton, John P.; Coutu, Ronald A.; Starman, LaVern

    2015-02-01

    There are numerous applications for micromirror arrays seen in our everyday lives. From flat screen televisions and computer monitors, found in nearly every home and office, to advanced military weapon systems and space vehicles, each application bringing with it a unique set of requirements. The microelectromechanical systems (MEMS) industry has researched many ways micromirror actuation can be accomplished and the different constraints on performance each design brings with it. This paper investigates a new "zipper" approach to electrostatically driven micromirrors with the intent of improving duel plane beam steering by coupling large deflection angles, over 30°, and a fast switching speed. To accomplish this, an extreme initial deflection is needed which can be reached using high stress bimorph beams. Currently this requires long beams and high voltage for the electrostatic pull in or slower electrothermal switching. The idea for this "zipper" approach is to stack multiple beams of a much shorter length and allow for the deflection of each beam to be added together in order to reach the required initial deflection height. This design requires much less pull-in voltage because the pull-in of one short beam will in turn reduce the height of the all subsequent beams, making it much easier to actuate. Using modeling and simulation software to characterize operations characteristics, different bimorph cantilever beam configurations are explored in order to optimize the design. These simulations show that this new "zipper" approach increases initial deflection as additional beams are added to the assembly without increasing the actuation voltage.

  6. TU-H-BRA-07: Design, Construction, and Installation of An Experimental Beam Line for the Development of MRI-Linac Compatible Electron Accelerator

    International Nuclear Information System (INIS)

    Whelan, B; Keall, P; Holloway, L; Gierman, S; Schmerge, J; Tantawi, S; Tremaine, A; Trautwein, A; Scott, B; Fahrig, R

    2016-01-01

    Purpose: MRI guided radiation therapy (MRIgRT) is a rapidly growing field; however, Linac operation in MRI fringe fields represents an ongoing challenge. We have previously shown in-silico that Linacs could be redesigned to function in the in-line orientation with no magnetic shielding by adopting an RF-gun configuration. Other authors have also published insilico studies of Linac operation in magnetic fields; however to date no experimental validation data is published. This work details the design, construction, and installation of an experimental beam line to validate our in-silico results. Methods: An RF-gun comprising 1.5 accelerating cells and capable of generating electron energies up to 3.2MeV is used. The experimental apparatus was designed to monitor both beam current (toroid current monitor), spot size (two phosphor screens with viewports), and generate peak magnetic fields of at least 1000G (three variable current electromagnetic coils). Thermal FEM simulations were developed to ensure coil temperature remained within 100degC. Other design considerations included beam disposal, vacuum maintenance, radiation shielding, earthquake safety, and machine protection interlocks. Results: The beam line has been designed, built, and installed in a radiation shielded bunker. Water cooling, power supplies, thermo-couples, cameras, and radiation shielding have been successfully connected and tested. Interlock testing, vacuum processing, and RF processing have been successfully completed. The first beam on is expected within weeks. The coil heating simulations show that with care, peak fields of up to 1200G (320G at cathode) can be produced using 40A current, which is well within the fields expected for MRI-Linac systems. The maximum coil temperature at this current was 84degC after 6 minutes. Conclusion: An experimental beam line has been constructed and installed at SLAC in order to experimentally characterise RF gun performance in in-line magnetic fields, validate

  7. Measured and simulated transport of 1.9 MeV laser-accelerated proton bunches through an integrated test beam line at 1 Hz

    Directory of Open Access Journals (Sweden)

    M. Nishiuchi

    2010-07-01

    Full Text Available A laser-driven repetition-rated 1.9 MeV proton beam line composed of permanent quadrupole magnets (PMQs, a radio frequency (rf phase rotation cavity, and a tunable monochromator is developed to evaluate and to test the simulation of laser-accelerated proton beam transport through an integrated system for the first time. In addition, the proton spectral modulation and focusing behavior of the rf phase rotation cavity device is monitored with input from a PMQ triplet. In the 1.9 MeV region we observe very weak proton defocusing by the phase rotation cavity. The final transmitted bunch duration and transverse profile are well predicted by the PARMILA particle transport code. The transmitted proton beam duration of 6 ns corresponds to an energy spread near 5% for which the transport efficiency is simulated to be 10%. The predictive capability of PARMILA suggests that it can be useful in the design of future higher energy transport beam lines as part of an integrated laser-driven ion accelerator system.

  8. Thermomechanical Characterization and Modeling of Superelastic Shape Memory Alloy Beams and Frames

    Science.gov (United States)

    Watkins, Ryan

    Of existing applications, the majority of shape memory alloy (SMA) devices consist of beam (orthodontic wire, eye glasses frames, catheter guide wires) and framed structures (cardiovascular stents, vena cava filters). Although uniaxial tension data is often sufficient to model basic beam behavior (which has been the main focus of the research community), the tension-compression asymmetry and complex phase transformation behavior of SMAs suggests more information is necessary to properly model higher complexity states of loading. In this work, SMA beams are experimentally characterized under general loading conditions (including tension, compression, pure bending, and buckling); furthermore, a model is developed with respect to general beam deformation based on the relevant phenomena observed in the experimental characterization. Stress induced phase transformation within superelastic SMA beams is shown to depend on not only the loading mode, but also kinematic constraints imposed by beam geometry (such as beam cross-section and length). In the cases of tension and pure bending, the structural behavior is unstable and corresponds to phase transformation localization and propagation. This unstable behavior is the result of a local level up--down--up stress/strain response in tension, which is measured here using a novel composite-based experimental technique. In addition to unstable phase transformation, intriguing post-buckling straightening is observed in short SMA columns during monotonic loading (termed unbuckling here). Based on this phenomenological understanding of SMA beam behavior, a trilinear based material law is developed in the context of a Shanley column model and is found to capture many of the relevant features of column buckling, including the experimentally observed unbuckling behavior. Due to the success of this model, it is generalized within the context of beam theory and, in conjunction with Bloch wave stability analysis, is used to model and

  9. Jet outflow and open field line measurements on the C-2U advanced beam-driven field-reversed configuration plasma experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sheftman, D., E-mail: dsheftman@trialphaenergy.com; Gupta, D.; Roche, T.; Thompson, M. C. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688-7010 (United States); Giammanco, F.; Conti, F.; Marsili, P.; Moreno, C. D. [Department of Physics, University of Pisa, Largo Bruno Pontecorvo 3, 56127 Pisa (Italy)

    2016-11-15

    Knowledge and control of the axial outflow of plasma particles and energy along open-magnetic-field lines are of crucial importance to the stability and longevity of the advanced beam-driven field-reversed configuration plasma. An overview of the diagnostic methods used to perform measurements on the open field line plasma on C-2U is presented, including passive Doppler impurity spectroscopy, microwave interferometry, and triple Langmuir probe measurements. Results of these measurements provide the jet ion temperature and axial velocity, electron density, and high frequency density fluctuations.

  10. FINITE ELEMENT MODELING OF CAMBER OF PRESTRESSED CONCRETE BEAMS

    Directory of Open Access Journals (Sweden)

    Peter P. Gaigerov

    2017-12-01

    Full Text Available For large-span reinforced concrete beam structures developed by the method of determining the camber due to the prestressing of a steel rope on the concrete. Performed numerical experiments to study the impact of various schemes layout prestressed reinforcement without bonding with concrete on the distribution of the relief efforts along the path of the reinforcement.

  11. Molecular Line Survey of CRL618 and Complete Modeling

    Science.gov (United States)

    Pardo, J. R.; Cernicharo, J.; Goicoechea, J. R.; Phillips, T. G.

    We present a complete survey and model of the emission from the C-rich protoplanetary nebula CRL 618 at the frequencies accessible with the IRAM-30m telescope (80.25-115.75 GHz, 131.25-179.25 GHz, and 204.25-275.25 GHz) and some results of still on-going observations at the Caltech Submillimeter Observatory (280-360 GHz). Although the number of lines detected is large (several hundreds), the number of chemical species from which they arise is rather small. In fact, lines from cyanopolyynes HC3N and HC5N dominate by far the long-wave spectrum of CRL618, with detection of numerous vibrationally excited states and isotopic substituted species. Most of detected species exhibit P-Cygni profiles at the lowest frequencies (3 mm window), and they evolve to pure emission as frequency increases. This fact can only be explained by the behavior of the continuum emission arising from the inner ultracompact HII region and surrounding dust. The data set itself has been used to characterize the continuum emission by averaging all the continuum measurements during the time span of the survey (~8 years). The physical parameters of the different gas regions have been established by studying the large number of detected cyanopolyynes lines. Using these constraints, the abundances of many other species relative to HC3N could also be determined and a general model, that reproduce the whole data set at a very detailed level of agreement, could be built. 1. Introduction The motivation to perform the complete millimeter line survey presented here with the IRAM-30m telescope has been to gather the most complete information on the molecular content in one particular stage (protoplanetary nebula, PPNe) of stellar evolution from the Asymptotic Giant Branch (AGB) to Planetary Nebulae (PN), of which CRL618 is the best example. Its chemical richness and its complex morphology are now very well known. Detailed chemical models for this object have been developed (Cernicharo 2004) indicating the

  12. Choice of theoretical model for beam scattering at accelerator output foil for particle energy determination

    International Nuclear Information System (INIS)

    Balagyra, V.S.; Ryabka, P.M.

    1999-01-01

    For measuring the charged particle energy calculations of mean square angles of electron beam multiple Coulomb scattering at output combined accelerator target were undertaken according to seven theoretical models. Mollier method showed the best agreement with experiments

  13. Modeling of a light elastic beam by a system of rigid bodies

    Directory of Open Access Journals (Sweden)

    Šalinić Slaviša

    2004-01-01

    Full Text Available This paper has shown that a light elastic beam, in the case of small elastic deformations, can be modeled by a kinematic chain without branching composed of rigid bodies which are connected by passive revolute or prismatic joints with corresponding springs in them. Elastic properties of the beam are modeled by the springs introduced. The potential energy of the elastic beam is expressed as a function of components of the vector of elastic displacement and the vector of elastic rotation calculated for the elastic centre of the beam, which results in the diagonal stiffness matrix of the beam. As the potential energy of the introduced system of bodies with springs is expressed in the function of relative joint displacements, the diagonal stiffness matrix is obtained. In addition, these two stiffness matrices are equal. The modeling process has been demonstrated on the example of an elastic beam rotating about a fixed vertical axis, with a rigid body whose mass is considerably larger than the beam mass fixed to its free end. Differential equations of motion have been formed for this mechanical system. The modeling technique described here aims at expanding of usage of well developed methods of dynamics of systems of rigid bodies to the analysis of systems with elastic bodies. .

  14. Lightning Surge Characteristics of an Actual Distribution Line and Validation of a Distribution Line Model for Lightning Overvoltage Studies

    Science.gov (United States)

    Matsuura, Susumu; Noda, Taku; Asakawa, Akira; Yokoyama, Shigeru

    For distribution lines in Japan, protection measures against lightning induced overvoltages have been taken and can be considered almost complete. The focus of lightning protection measures has moved to overvoltages due to direct lightning strokes. Studies of such overvoltages require simulations using the EMTP (Electro-Magnetic Transients Program), and components of a distribution line must be modeled appropriately in the EMTP simulation environment. The authors have proposed an EMTP model of a distribution line in a separate paper. This paper consists of two parts. The first part presents surge characteristics of a distribution line obtained by measurement using an actual-scale test distribution line. Especially, the result reveals noteworthy characteristics of the surge impedance of a reinforced concrete pole and the wavefront-time dependence of insulator voltages. The second part presents validation of the distribution line model previously proposed by the authors. The validation shows that the distribution line model accurately reproduces the measured voltage and current waveforms for various wavefront times of injected currents.

  15. Stochastic Higher Spin Vertex Models on the Line

    Science.gov (United States)

    Corwin, Ivan; Petrov, Leonid

    2016-04-01

    We introduce a four-parameter family of interacting particle systems on the line, which can be diagonalized explicitly via a complete set of Bethe ansatz eigenfunctions, and which enjoy certain Markov dualities. Using this, for the systems started in step initial data, we write down nested contour integral formulas for moments and Fredholm determinant formulas for Laplace-type transforms. Taking various choices or limits of parameters, this family degenerates to many of the known exactly solvable models in the Kardar-Parisi-Zhang universality class, as well as leads to many new examples of such models. In particular, asymmetric simple exclusion process, the stochastic six-vertex model, q-totally asymmetric simple exclusion process and various directed polymer models all arise in this manner. Our systems are constructed from stochastic versions of the R-matrix related to the six-vertex model. One of the key tools used here is the fusion of R-matrices and we provide a probabilistic proof of this procedure.

  16. A simplified model predicting the weight of the load carrying beam in a wind turbine blade

    DEFF Research Database (Denmark)

    Mikkelsen, Lars Pilgaard

    2016-01-01

    Based on a simplified beam model, the loads, stresses and deflections experienced by a wind turbine blade of a given length is estimated. Due to the simplicity of the model used, the model is well suited for work investigating scaling effects of wind turbine blades. Presently, the model is used t...

  17. Light scattering of a Bessel beam by a nucleated biological cell: An eccentric sphere model

    Science.gov (United States)

    Wang, Jia Jie; Han, Yi Ping; Chang, Jiao Yong; Chen, Zhu Yang

    2018-02-01

    Within the framework of generalized Lorenz-Mie theory (GLMT), an eccentrically stratified dielectric sphere model illuminated by an arbitrarily incident Bessel beam is applied to investigate the scattering characteristics of a single nucleated biological cell. The Bessel beam propagating in an arbitrary direction is expanded in terms of vector spherical wave functions (VSWFs), where the beam shape coefficients (BSCs) are calculated rigorously in a closed analytical form. The effects of the half-cone angle of Bessel beam, the location of the particle in the beam, the size ratio of nucleus to cell, and the location of the nucleus inside the cell on the scattering properties of a nucleated cell are analyzed. The results provide useful references for optical diagnostic and imaging of particle having nucleated structure.

  18. Analytic modeling, simulation and interpretation of broadband beam coupling impedance bench measurements

    Energy Technology Data Exchange (ETDEWEB)

    Niedermayer, U., E-mail: niedermayer@temf.tu-darmstadt.de [Institut für Theorie Elektromagnetischer Felder (TEMF), Technische Universität Darmstadt, Schloßgartenstraße 8, 64289 Darmstadt (Germany); Eidam, L. [Institut für Theorie Elektromagnetischer Felder (TEMF), Technische Universität Darmstadt, Schloßgartenstraße 8, 64289 Darmstadt (Germany); Boine-Frankenheim, O. [Institut für Theorie Elektromagnetischer Felder (TEMF), Technische Universität Darmstadt, Schloßgartenstraße 8, 64289 Darmstadt (Germany); GSI Helmholzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt (Germany)

    2015-03-11

    First, a generalized theoretical approach towards beam coupling impedances and stretched-wire measurements is introduced. Applied to a circular symmetric setup, this approach allows to compare beam and wire impedances. The conversion formulas for TEM scattering parameters from measurements to impedances are thoroughly analyzed and compared to the analytical beam impedance solution. A proof of validity for the distributed impedance formula is given. The interaction of the beam or the TEM wave with dispersive material such as ferrite is discussed. The dependence of the obtained beam impedance on the relativistic velocity β is investigated and found as material property dependent. Second, numerical simulations of wakefields and scattering parameters are compared. The applicability of scattering parameter conversion formulas for finite device length is investigated. Laboratory measurement results for a circularly symmetric test setup, i.e. a ferrite ring, are shown and compared to analytic and numeric models. The optimization of the measurement process and error reduction strategies are discussed.

  19. Experimental characterization and physical modelling of the dose distribution of scanned proton pencil beams

    International Nuclear Information System (INIS)

    Pedroni, E; Scheib, S; Boehringer, T; Coray, A; Grossmann, M; Lin, S; Lomax, A

    2005-01-01

    In this paper we present the pencil beam dose model used for treatment planning at the PSI proton gantry, the only system presently applying proton therapy with a beam scanning technique. The scope of the paper is to give a general overview on the various components of the dose model, on the related measurements and on the practical parametrization of the results. The physical model estimates from first physical principles absolute dose normalized to the number of incident protons. The proton beam flux is measured in practice by plane-parallel ionization chambers (ICs) normalized to protons via Faraday-cup measurements. It is therefore possible to predict and deliver absolute dose directly from this model without other means. The dose predicted in this way agrees very well with the results obtained with ICs calibrated in a cobalt beam. Emphasis is given in this paper to the characterization of nuclear interaction effects, which play a significant role in the model and are the major source of uncertainty in the direct estimation of the absolute dose. Nuclear interactions attenuate the primary proton flux, they modify the shape of the depth-dose curve and produce a faint beam halo of secondary dose around the primary proton pencil beam in water. A very simple beam halo model has been developed and used at PSI to eliminate the systematic dependences of the dose observed as a function of the size of the target volume. We show typical results for the relative (using a CCD system) and absolute (using calibrated ICs) dosimetry, routinely applied for the verification of patient plans. With the dose model including the nuclear beam halo we can predict quite precisely the dose directly from treatment planning without renormalization measurements, independently of the dose, shape and size of the dose fields. This applies also to the complex non-homogeneous dose distributions required for the delivery of range-intensity-modulated proton therapy, a novel therapy technique

  20. Photon beam modelling with Pinnacle3 Treatment Planning System for a Rokus M Co-60 Machine

    International Nuclear Information System (INIS)

    Dulcescu, Mihaela; Murgulet Cristian

    2008-01-01

    The basic relationships of the convolution/superposition dose calculation technique are reviewed, and a modelling technique that can be used for obtaining a satisfactory beam model for a commercially available convolution/superposition-based treatment planning system is described. A fluence energy spectrum for a Co-60 treatment machine obtained from a Monte Carlo simulation was used for modelling the fluence spectrum for a Rokus M machine. In order to achieve this model we measured the depth dose distribution and the dose profiles with a Wellhofer dosimetry system. The primary fluence was iteratively modelled by comparing the computed depth dose curves and beam profiles with the depth dose curves and crossbeam profiles measured in a water phantom. The objective of beam modelling is to build a model of the primary fluence that the patient is exposed to, which can then be used for the calculation of the dose deposited in the patient. (authors)

  1. On-Line Core Thermal-Hydraulic Model Improvement

    Energy Technology Data Exchange (ETDEWEB)

    In, Wang Kee; Chun, Tae Hyun; Oh, Dong Seok; Shin, Chang Hwan; Hwang, Dae Hyun; Seo, Kyung Won

    2007-02-15

    The objective of this project is to implement a fast-running 4-channel based code CETOP-D in an advanced reactor core protection calculator system(RCOPS). The part required for the on-line calculation of DNBR were extracted from the source of the CETOP-D code based on analysis of the CETOP-D code. The CETOP-D code was revised to maintain the input and output variables which are the same as in CPC DNBR module. Since the DNBR module performs a complex calculation, it is divided into sub-modules per major calculation step. The functional design requirements for the DNBR module is documented and the values of the database(DB) constants were decided. This project also developed a Fortran module(BEST) of the RCOPS Fortran Simulator and a computer code RCOPS-SDNBR to independently calculate DNBR. A test was also conducted to verify the functional design and DB of thermal-hydraulic model which is necessary to calculate the DNBR on-line in RCOPS. The DNBR margin is expected to increase by 2%-3% once the CETOP-D code is used to calculate the RCOPS DNBR. It should be noted that the final DNBR margin improvement could be determined in the future based on overall uncertainty analysis of the RCOPS.

  2. Evaluation of the Actuator Line Model with coarse resolutions

    Science.gov (United States)

    Draper, M.; Usera, G.

    2015-06-01

    The aim of the present paper is to evaluate the Actuator Line Model (ALM) in spatial resolutions coarser than what is generally recommended, also using larger time steps. To accomplish this, the ALM has been implemented in the open source code caffa3d.MBRi and validated against experimental measurements of two wind tunnel campaigns (stand alone wind turbine and two wind turbines in line, case A and B respectively), taking into account two spatial resolutions: R/8 and R/15 (R is the rotor radius). A sensitivity analysis in case A was performed in order to get some insight into the influence of the smearing factor (3D Gaussian distribution) and time step size in power and thrust, as well as in the wake, without applying a tip loss correction factor (TLCF), for one tip speed ratio (TSR). It is concluded that as the smearing factor is larger or time step size is smaller the power is increased, but the velocity deficit is not as much affected. From this analysis, a smearing factor was obtained in order to calculate precisely the power coefficient for that TSR without applying TLCF. Results with this approach were compared with another simulation choosing a larger smearing factor and applying Prandtl's TLCF, for three values of TSR. It is found that applying the TLCF improves the power estimation and weakens the influence of the smearing factor. Finally, these 2 alternatives were tested in case B, confirming that conclusion.

  3. A new tectonic model for the Cameroon Line, Central Africa

    Science.gov (United States)

    Moreau, C.; Regnoult, J.-M.; Déruelle, B.; Robineau, B.

    1987-10-01

    The Cameroon Line, a major geological feature in Central Africa, has been considered successively as a series of horsts and grabens, a continental rift and a mega-shear zone. It is marked out by about 60 anorogenic complexes and a dozen volcanic centres, all of which have alkaline affinity. Remote sensing allows us recognition of the main lineament trends: N70°, N-S, N135° and E-W, while autocorrelation analysis reveals a major fault zone striking N30° in western Cameroon and N15° in the northern region. A mega left-lateral shear zone is the model that best accounts for the fracture pattern and associated features such as linear and circular structures alignment of subvolcanic complexes, syntectonic leucogranites marking out older shear zones and vein dykes. The N70° Adamawa fault zone, a Pan-African fracture reworked during Albian-Aptian times, is the only shear zone of continental scale that could have initiated "en echelon" mega-tension gashes within the Cameroon Line during a Cainozoic left-lateral transcurrent movement.

  4. Beam diagnostics

    International Nuclear Information System (INIS)

    Bogaty, J.; Clifft, B.E.; Zinkann, G.P.; Pardo, R.C.

    1995-01-01

    The ECR-PII injector beam line is operated at a fixed ion velocity. The platform high voltage is chosen so that all ions have a velocity of 0.0085c at the PII entrance. If a previous tune configuration for the linac is to be used, the beam arrival time must be matched to the previous tune as well. A nondestructive beam-phase pickup detector was developed and installed at the entrance to the PII linac. This device provides continuous phase and beam current information and allows quick optimization of the beam injected into PII. Bunches traverse a short tubular electrode thereby inducing displacement currents. These currents are brought outside the vacuum interface where a lumped inductance resonates electrode capacitance at one of the bunching harmonic frequencies. This configuration yields a basic sensitivity of a few hundred millivolts signal per microampere of beam current. Beam-induced radiofrequency signals are summed against an offset frequency generated by our master oscillator. The resulting kilohertz difference frequency conveys beam intensity and bunch phase information which is sent to separate processing channels. One channel utilizes a phase locked loop which stabilizes phase readings if beam is unstable. The other channel uses a linear full wave active rectifier circuit which converts kilohertz sine wave signal amplitude to a D.C. voltage representing beam current. A prototype set of electronics is now in use with the detector and we began to use the system in operation to set the arrival beam phase. A permanent version of the electronics system for the phase detector is now under construction. Additional nondestructive beam intensity and phase monitors at the open-quotes Boosterclose quotes and open-quotes ATLASclose quotes linac sections are planned as well as on some of the high-energy beam lines. Such a monitor will be particularly useful for FMA experiments where the primary beam hits one of the electric deflector plates

  5. FE Modelling of the Seismic Behavior of Wide Beam-Column Joints Strengthened with CFRP Systems

    Directory of Open Access Journals (Sweden)

    Giuseppe Santarsiero

    2018-02-01

    Full Text Available A large share of reinforced concrete (RC framed buildings is provided with wide beams being a type of beam allowing greater freedom in the architectural arrangement of interiors, beyond further advantage due to fewer formworks needed during the construction. Nevertheless, little attention has been devoted to the seismic vulnerability of this kind of framed RC buildings as well as to the study of strengthening systems purposely developed for wide beams and wide beam-column connections. Under these premises, this paper proposes simple strengthening solutions made by Fibre Reinforced Polymers (FRP systems able to effectively improve seismic capacity through feasible arrangement suitable in case a wide beam is present. On the basis of wide beam-column joints previously tested without strengthening system, detailed nonlinear finite element models were calibrated. Then, an FRP strengthening intervention based on a brand new arrangement was modeled in order to perform additional simulations under seismic actions. This way, the effectiveness of the strengthening intervention was assessed finding out that significant strength and ductility increments were achieved with a relatively simple and cheap strengthening arrangement. Additional research would be desirable in the form of experimental tests on the simulated wide beam-column joints.

  6. Vibration energy harvesting by a Timoshenko beam model and piezoelectric transducer

    Science.gov (United States)

    Stoykov, S.; Litak, G.; Manoach, E.

    2015-11-01

    An electro-mechanical system of vibrational energy harvesting is studied. The beam is excited by external and kinematic periodic forces and damped by an electrical resistor through the coupled piezoelectric transducer. Nonlinearities are introduced by stoppers limiting the transverse displacements of the beam. The interaction between the beam and the stoppers is modeled as Winkler elastic foundation. The mechanical properties of the piezoelectric layer are taken into account and the beam is modeled as a composite structure. For the examined composite beam, the geometrically nonlinear version of the Timoshenko's beam theory is assumed. The equations of motion are derived by the principle of virtual work considering large deflections. An isogeometric approach is applied for space discretization and B-Splines are used as shape functions. Finally, the power output and the efficiency of the system due to harmonic excitations are discussed. The influence of the position of the stoppers and their length on the dynamics of the beam and consequently on the power output are analyzed and presented.

  7. GPU-Powered Modelling of Nonlinear Effects due to Head-On Beam-Beam Interactions in High-Energy Hadron Colliders.

    CERN Document Server

    Furuseth, Sondre

    2017-01-01

    The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. This report discusses results from an implementation of the weak-strong model, studying the effects of head-on beam-beam interactions. The assumptions has been shown to be valid for configurations where the growth and losses of the beam are small. The tracking has been done using an original code which applies graphic cards to reduce the computation time. The bunches in the beams have been modelled cylindrically symmetrical, based on a Gaussian distribution in three dimensions. This choice fits well with bunches...

  8. PI-line-based image reconstruction in helical cone-beam computed tomography with a variable pitch

    International Nuclear Information System (INIS)

    Zou Yu; Pan Xiaochuan; Xia Dan; Wang Ge

    2005-01-01

    Current applications of helical cone-beam computed tomography (CT) involve primarily a constant pitch where the translating speed of the table and the rotation speed of the source-detector remain constant. However, situations do exist where it may be more desirable to use a helical scan with a variable translating speed of the table, leading a variable pitch. One of such applications could arise in helical cone-beam CT fluoroscopy for the determination of vascular structures through real-time imaging of contrast bolus arrival. Most of the existing reconstruction algorithms have been developed only for helical cone-beam CT with constant pitch, including the backprojection-filtration (BPF) and filtered-backprojection (FBP) algorithms that we proposed previously. It is possible to generalize some of these algorithms to reconstruct images exactly for helical cone-beam CT with a variable pitch. In this work, we generalize our BPF and FBP algorithms to reconstruct images directly from data acquired in helical cone-beam CT with a variable pitch. We have also performed a preliminary numerical study to demonstrate and verify the generalization of the two algorithms. The results of the study confirm that our generalized BPF and FBP algorithms can yield exact reconstruction in helical cone-beam CT with a variable pitch. It should be pointed out that our generalized BPF algorithm is the only algorithm that is capable of reconstructing exactly region-of-interest image from data containing transverse truncations

  9. Performance Analysis of GFDL's GCM Line-By-Line Radiative Transfer Model on GPU and MIC Architectures

    Science.gov (United States)

    Menzel, R.; Paynter, D.; Jones, A. L.

    2017-12-01

    Due to their relatively low computational cost, radiative transfer models in global climate models (GCMs) run on traditional CPU architectures generally consist of shortwave and longwave parameterizations over a small number of wavelength bands. With the rise of newer GPU and MIC architectures, however, the performance of high resolution line-by-line radiative transfer models may soon approach those of the physical parameterizations currently employed in GCMs. Here we present an analysis of the current performance of a new line-by-line radiative transfer model currently under development at GFDL. Although originally designed to specifically exploit GPU architectures through the use of CUDA, the radiative transfer model has recently been extended to include OpenMP in an effort to also effectively target MIC architectures such as Intel's Xeon Phi. Using input data provided by the upcoming Radiative Forcing Model Intercomparison Project (RFMIP, as part of CMIP 6), we compare model results and performance data for various model configurations and spectral resolutions run on both GPU and Intel Knights Landing architectures to analogous runs of the standard Oxford Reference Forward Model on traditional CPUs.

  10. A Business Maturity Model of Software Product Line Engineering

    OpenAIRE

    Ahmed, Faheem; Capretz, Luiz Fernando

    2015-01-01

    In the recent past, software product line engineering has become one of the most promising practices in software industry with the potential to substantially increase the software development productivity. Software product line engineering approach spans the dimensions of business, architecture, software engineering process and organization. The increasing popularity of software product line engineering in the software industry necessitates a process maturity evaluation methodology. According...

  11. Modeling laser beam diffraction and propagation by the mode-expansion method.

    Science.gov (United States)

    Snyder, James J

    2007-08-01

    In the mode-expansion method for modeling propagation of a diffracted beam, the beam at the aperture can be expanded as a weighted set of orthogonal modes. The parameters of the expansion modes are chosen to maximize the weighting coefficient of the lowest-order mode. As the beam propagates, its field distribution can be reconstructed from the set of weighting coefficients and the Gouy phase of the lowest-order mode. We have developed a simple procedure to implement the mode-expansion method for propagation through an arbitrary ABCD matrix, and we have demonstrated that it is accurate in comparison with direct calculations of diffraction integrals and much faster.

  12. Laser Beam Propagation Through Inhomogeneous Media with Shock-Like Profiles: Modeling and Computing

    Science.gov (United States)

    Adamovsky, Grigory; Ida, Nathan

    1997-01-01

    Wave propagation in inhomogeneous media has been studied for such diverse applications as propagation of radiowaves in atmosphere, light propagation through thin films and in inhomogeneous waveguides, flow visualization, and others. In recent years an increased interest has been developed in wave propagation through shocks in supersonic flows. Results of experiments conducted in the past few years has shown such interesting phenomena as a laser beam splitting and spreading. The paper describes a model constructed to propagate a laser beam through shock-like inhomogeneous media. Numerical techniques are presented to compute the beam through such media. The results of computation are presented, discussed, and compared with experimental data.

  13. New models for energy beam machining enable accurate generation of free forms.

    Science.gov (United States)

    Axinte, Dragos; Billingham, John; Bilbao Guillerna, Aitor

    2017-09-01

    We demonstrate that, despite differences in their nature, many energy beam controlled-depth machining processes (for example, waterjet, pulsed laser, focused ion beam) can be modeled using the same mathematical framework-a partial differential evolution equation that requires only simple calibrations to capture the physics of each process. The inverse problem can be solved efficiently through the numerical solution of the adjoint problem and leads to beam paths that generate prescribed three-dimensional features with minimal error. The viability of this modeling approach has been demonstrated by generating accurate free-form surfaces using three processes that operate at very different length scales and with different physical principles for material removal: waterjet, pulsed laser, and focused ion beam machining. Our approach can be used to accurately machine materials that are hard to process by other means for scalable applications in a wide variety of industries.

  14. Theoretical model of a polarization diffractive elements for the light beams conversion holographic formation in PDLCs

    Science.gov (United States)

    Sharangovich, Sergey N.; Semkin, Artem O.

    2017-12-01

    In this work a theoretical model of the holographic formation of the polarization diffractive optical elements for the transformation of Gaussian light beams into Bessel-like ones in polymer-dispersed liquid crystals (PDLC) is developed. The model is based on solving the equations of photo-induced Fredericks transition processes for polarization diffractive elements formation by orthogonally polarized light beams with inhomogeneous amplitude and phase profiles. The results of numerical simulation of the material's dielectric tensor changing due to the structure's formation process are presented for various recording beams' polarization states. Based on the results of numerical simulation, the ability to form the diffractive optical elements for light beams transformation by the polarization holography methods is shown.

  15. The development of a curved beam element model applied to finite elements method

    International Nuclear Information System (INIS)

    Bento Filho, A.

    1980-01-01

    A procedure for the evaluation of the stiffness matrix for a thick curved beam element is developed, by means of the minimum potential energy principle, applied to finite elements. The displacement field is prescribed through polynomial expansions, and the interpolation model is determined by comparison of results obtained by the use of a sample of different expansions. As a limiting case of the curved beam, three cases of straight beams, with different dimensional ratios are analised, employing the approach proposed. Finally, an interpolation model is proposed and applied to a curved beam with great curvature. Desplacements and internal stresses are determined and the results are compared with those found in the literature. (Author) [pt

  16. Quantitative Analysis of Probabilistic Models of Software Product Lines with Statistical Model Checking

    DEFF Research Database (Denmark)

    ter Beek, Maurice H.; Legay, Axel; Lluch Lafuente, Alberto

    2015-01-01

    We investigate the suitability of statistical model checking techniques for analysing quantitative properties of software product line models with probabilistic aspects. For this purpose, we enrich the feature-oriented language FLAN with action rates, which specify the likelihood of exhibiting...... particular behaviour or of installing features at a specific moment or in a specific order. The enriched language (called PFLAN) allows us to specify models of software product lines with probabilistic configurations and behaviour, e.g. by considering a PFLAN semantics based on discrete-time Markov chains....... The Maude implementation of PFLAN is combined with the distributed statistical model checker MultiVeStA to perform quantitative analyses of a simple product line case study. The presented analyses include the likelihood of certain behaviour of interest (e.g. product malfunctioning) and the expected average...

  17. Quantitative Analysis of Probabilistic Models of Software Product Lines with Statistical Model Checking

    Directory of Open Access Journals (Sweden)

    Maurice H. ter Beek

    2015-04-01

    Full Text Available We investigate the suitability of statistical model checking techniques for analysing quantitative properties of software product line models with probabilistic aspects. For this purpose, we enrich the feature-oriented language FLan with action rates, which specify the likelihood of exhibiting particular behaviour or of installing features at a specific moment or in a specific order. The enriched language (called PFLan allows us to specify models of software product lines with probabilistic configurations and behaviour, e.g. by considering a PFLan semantics based on discrete-time Markov chains. The Maude implementation of PFLan is combined with the distributed statistical model checker MultiVeStA to perform quantitative analyses of a simple product line case study. The presented analyses include the likelihood of certain behaviour of interest (e.g. product malfunctioning and the expected average cost of products.

  18. Nonsmooth Modeling of Vibro-Impacting Euler-Bernoulli Beam

    Directory of Open Access Journals (Sweden)

    C. P. Vyasarayani

    2012-01-01

    Full Text Available A new technique to simulate nonsmooth motions occurring in vibro-impacting continuous systems is proposed. Sticking motions that are encountered during vibro-impact simulation are imposed exactly using a Lagrange multiplier, which represents the normal reaction force between the continuous system and the obstacle. The expression for the Lagrange multiplier is developed in closed form. The developed theory is demonstrated by numerically simulating the forced response of a pinned-pinned beam impacting a point-like rigid obstacle.

  19. Beam conditions for radiation generated by an electromagnetic Gaussian Schell-model source.

    Science.gov (United States)

    Korotkova, Olga; Salem, Mohamed; Wolf, Emil

    2004-06-01

    It was shown recently that the basic properties of a fluctuating electromagnetic beam can be derived from knowledge of a 2 x 2 cross-spectral density matrix of the electric field in the source plane. However, not every such matrix represents a source that will generate a beamlike field. We derive conditions that the matrix must satisfy for the source to generate an electromagnetic Gaussian Schell-model beam.

  20. Design of experiments in medical physics: Application to the AAA beam model validation.

    Science.gov (United States)

    Dufreneix, S; Legrand, C; Di Bartolo, C; Bremaud, M; Mesgouez, J; Tiplica, T; Autret, D

    2017-09-01

    The purpose of this study is to evaluate the usefulness of the design of experiments in the analysis of multiparametric problems related to the quality assurance in radiotherapy. The main motivation is to use this statistical method to optimize the quality assurance processes in the validation of beam models. Considering the Varian Eclipse system, eight parameters with several levels were selected: energy, MLC, depth, X, Y 1 and Y 2 jaw dimensions, wedge and wedge jaw. A Taguchi table was used to define 72 validation tests. Measurements were conducted in water using a CC04 on a TrueBeam STx, a TrueBeam Tx, a Trilogy and a 2300IX accelerator matched by the vendor. Dose was computed using the AAA algorithm. The same raw data was used for all accelerators during the beam modelling. The mean difference between computed and measured doses was 0.1±0.5% for all beams and all accelerators with a maximum difference of 2.4% (under the 3% tolerance level). For all beams, the measured doses were within 0.6% for all accelerators. The energy was found to be an influencing parameter but the deviations observed were smaller than 1% and not considered clinically significant. Designs of experiment can help define the optimal measurement set to validate a beam model. The proposed method can be used to identify the prognostic factors of dose accuracy. The beam models were validated for the 4 accelerators which were found dosimetrically equivalent even though the accelerator characteristics differ. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.