Science.gov

Sample records for beam energy civa

  1. Civa

    NASA Astrophysics Data System (ADS)

    Bibring, J.-P.; Lamy, P.; Langevin, Y.; Soufflot, A.; Berthé, M.; Borg, J.; Poulet, F.; Mottola, S.

    2007-02-01

    CIVA ( Comet Infrared and Visible Analyser) is an integrated set of imaging instruments, designed to characterize the 360∘ panorama (CIVA-P) as seen from the Rosetta Lander Philae, and to study surface and subsurface samples (CIVA-M). CIVA-P is a panoramic stereo camera, while CIVA-M is an optical microscope coupled to a near infrared microscopic hyperspectral imager. CIVA shares a common Imaging Main Electronics (IME) with ROLIS. CIVA-P will characterize the landing site, with an angular sampling (IFOV) of 1.1 mrad: each pixel will image a 1 mm size feature at the distance of the landing legs, and a few metres at the local horizon. The panorama will be mapped by 6 identical miniaturized micro-cameras covering contiguous FOV, with their optical axis 60∘ apart. Stereoscopic capability will be provided by an additional micro-camera, identical to and co-aligned with one of the panoramic micro-camera, with its optical axis displaced by 10 cm. CIVA-M combines two ultra-compact and miniaturised microscopes, one operating in the visible and one constituting an IR hyperspectral imaging spectrometer: they will characterize, by non-destructive analyses, the texture, the albedo, the molecular and the mineralogical composition of each of the samples provided by the Sample Drill and Distribution (SD2) system. For the optical microscope, the spatial sampling is 7 μm; for the IR, the spectral range (1 4 μm) and the spectral sampling (5 nm) have been chosen to allow identification of most minerals, ices and organics, on each pixel, 40 μm in size. After being studied by CIVA, the sample could be analysed by a subsequent experiment (PTOLEMY and/or COSAC). The process would be repeated for each sample obtained at different depths and/or locations.

  2. Electron and optical beam testing of integrated circuits using CIVA, LIVA, and LECIVA

    SciTech Connect

    Cole, E.I. Jr.

    1995-09-01

    Charge-Induced Voltage Alteration (CIVA), Light-Induced Voltage Alteration, (LIVA), and Low Energy CIVA (LECIVA) are three new failure analysis imaging techniques developed to quickly localize defects on ICs. All three techniques utilize the voltage fluctuations of a constant current power supply as an electron or photon beam is scanned across an IC. CIVA and LECIVA yield rapid localization of open interconnections on ICs. LIVA allows quick localization of open-circuited and damaged semiconductor junctions. LIVA can also be used to image transistor logic states and can be performed from the backside of ICs with an infrared laser source. The physics of signal generation for each technique and examples of their use in failure analysis are described.

  3. Experiment vs simulation RT WFNDEC 2014 benchmark: CIVA results

    SciTech Connect

    Tisseur, D. Costin, M. Rattoni, B. Vienne, C. Vabre, A. Cattiaux, G.; Sollier, T.

    2015-03-31

    The French Atomic Energy Commission and Alternative Energies (CEA) has developed for years the CIVA software dedicated to simulation of NDE techniques such as Radiographic Testing (RT). RT modelling is achieved in CIVA using combination of a determinist approach based on ray tracing for transmission beam simulation and a Monte Carlo model for the scattered beam computation. Furthermore, CIVA includes various detectors models, in particular common x-ray films and a photostimulable phosphor plates. This communication presents the results obtained with the configurations proposed in the World Federation of NDEC 2014 RT modelling benchmark with the RT models implemented in the CIVA software.

  4. Advances of Simulation and Expertise Capabilities in CIVA Platform

    NASA Astrophysics Data System (ADS)

    Le Ber, L.; Calmon, P.; Sollier, Th.; Mahaut, S.; Benoist, Ph.

    2006-03-01

    Simulation is more and more widely used by the different actors of industrial NDT. The French Atomic Energy Commission (CEA) launched the development of expertise software for NDT named CIVA which, at its beginning, only contained ultrasonic models from CEA laboratories. CIVA now includes Eddy current simulation tools while present work aims at facilitating integration of algorithms and models from different laboratories and to include X-ray modeling. This communication gives an overview of existing CIVA capabilities and its evolution towards an integration platform.

  5. CIVA: an expertise platform for simulation and processing NDT data.

    PubMed

    Calmon, P; Mahaut, S; Chatillon, S; Raillon, R

    2006-12-22

    Ultrasonic modeling and simulation are more and more widely used by the different actors of industrial NDT. The applications are numerous and show a great variety: help for diagnosis, data reconstruction, performance demonstration, probe design and inspection parameters settling, virtual testing etc. The CEA (the French Atomic Energy Commission) is strongly involved in this evolution with the development of the CIVA expertise platform which gathers in the same software advanced processing and modeling tools. In the aim of fulfilling requirements of an intensive use the choice has been made to mainly adopt semi-analytical approximated methods. The wave propagation modeling is based on an integral formulation of the radiated field and applies the so-called pencil method. The modeling of beam-defect interaction and echoes formation mechanisms apply approximated theories such as Kirchhoff approximation or GTD. Over the years and with successive versions of the software, this approach is enriched by adaptations and improvements of the existing models or by new models, in order to extend the field of applicability of the simulation.

  6. High energy beam lines

    NASA Astrophysics Data System (ADS)

    Marchetto, M.; Laxdal, R. E.

    2014-01-01

    The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

  7. Beamed energy propulsion

    NASA Technical Reports Server (NTRS)

    Shoji, James M.

    1992-01-01

    Beamed energy concepts offer an alternative for an advanced propulsion system. The use of a remote power source reduces the weight of the propulsion system in flight and this, combined with the high performance, provides significant payload gains. Within the context of this study's baseline scenario, two beamed energy propulsion concepts are potentially attractive: solar thermal propulsion and laser thermal propulsion. The conceived beamed energy propulsion devices generally provide low thrust (tens of pounds to hundreds of pounds); therefore, they are typically suggested for cargo transportation. For the baseline scenario, these propulsion system can provide propulsion between the following nodes: (1) low Earth orbit to geosynchronous Earth orbit; (2) low Earth orbit to low lunar orbit; (3) low lunar orbit to low Mars orbit--only solar thermal; and (4) lunar surface to low lunar orbit--only laser thermal.

  8. Implementation and evaluation of two helical CT reconstruction algorithms in CIVA

    NASA Astrophysics Data System (ADS)

    Banjak, H.; Costin, M.; Vienne, C.; Kaftandjian, V.

    2016-02-01

    The large majority of industrial CT systems reconstruct the 3D volume by using an acquisition on a circular trajec-tory. However, when inspecting long objects which are highly anisotropic, this scanning geometry creates severe artifacts in the reconstruction. For this reason, the use of an advanced CT scanning method like helical data acquisition is an efficient way to address this aspect known as the long-object problem. Recently, several analytically exact and quasi-exact inversion formulas for helical cone-beam reconstruction have been proposed. Among them, we identified two algorithms of interest for our case. These algorithms are exact and of filtered back-projection structure. In this work we implemented the filtered-backprojection (FBP) and backprojection-filtration (BPF) algorithms of Zou and Pan (2004). For performance evaluation, we present a numerical compari-son of the two selected algorithms with the helical FDK algorithm using both complete (noiseless and noisy) and truncated data generated by CIVA (the simulation platform for non-destructive testing techniques developed at CEA).

  9. Integrated circuit failure analysis by low-energy charge-induced voltage alteration

    DOEpatents

    Cole, E.I. Jr.

    1996-06-04

    A scanning electron microscope apparatus and method are described for detecting and imaging open-circuit defects in an integrated circuit (IC). The invention uses a low-energy high-current focused electron beam that is scanned over a device surface of the IC to generate a charge-induced voltage alteration (CIVA) signal at the location of any open-circuit defects. The low-energy CIVA signal may be used to generate an image of the IC showing the location of any open-circuit defects. A low electron beam energy is used to prevent electrical breakdown in any passivation layers in the IC and to minimize radiation damage to the IC. The invention has uses for IC failure analysis, for production-line inspection of ICs, and for qualification of ICs. 5 figs.

  10. Integrated circuit failure analysis by low-energy charge-induced voltage alteration

    DOEpatents

    Cole, Jr., Edward I.

    1996-01-01

    A scanning electron microscope apparatus and method are described for detecting and imaging open-circuit defects in an integrated circuit (IC). The invention uses a low-energy high-current focused electron beam that is scanned over a device surface of the IC to generate a charge-induced voltage alteration (CIVA) signal at the location of any open-circuit defects. The low-energy CIVA signal may be used to generate an image of the IC showing the location of any open-circuit defects. A low electron beam energy is used to prevent electrical breakdown in any passivation layers in the IC and to minimize radiation damage to the IC. The invention has uses for IC failure analysis, for production-line inspection of ICs, and for qualification of ICs.

  11. Energy Focusability of Annular Beams

    NASA Astrophysics Data System (ADS)

    Astadjov, Dimo N.

    2010-01-01

    A simulation of coherent annular flat two-level beams by two-dimensional Fast Fourier Transform is presented. After parameterization of the source beam (the `input') we examined the influence of its parameters on the shape and proportions of the output beam profile. The output pattern has a prominent central peak and faint rings concentrically surrounding it. The fraction of the central peak energy to the whole energy of beam, PF0 gives a notion of energy spread within the focal spot: PF0 is a function of beam annularity, k (i.e. `inside diameter/outside diameter' ratio) and the intensity dip, Idip of annulus central area (i.e. ring intensity minus central-bottom intensity, normalized). Up to k = 0.8 and Idip = 0.75, PF0 does not change too much—it is ⩾0.7 which is ⩾90% of PF0 maximum (0.778 at k = 0 and Idip = 0). Simulations revealed that even great changes in the shape of input beam annulus lead to small variations in the energy spread of output beam profile in the range of practical use of coherent annular beams.

  12. Intense low energy positron beams

    SciTech Connect

    Lynn, K.G.; Jacobsen, F.M.

    1993-12-31

    Intense positron beams are under development or being considered at several laboratories. Already today a few accelerator based high intensity, low brightness e{sup +} beams exist producing of the order of 10{sup 8} {minus} 10{sup 9} e{sup +}/sec. Several laboratories are aiming at high intensity, high brightness e{sup +} beams with intensities greater than 10{sup 9} e{sup +}/sec and current densities of the order of 10{sup 13} {minus} 10{sup 14} e{sup +} sec{sup {minus}} {sup 1}cm{sup {minus}2}. Intense e{sup +} beams can be realized in two ways (or in a combination thereof) either through a development of more efficient B{sup +} moderators or by increasing the available activity of B{sup +} particles. In this review we shall mainly concentrate on the latter approach. In atomic physics the main trust for these developments is to be able to measure differential and high energy cross-sections in e{sup +} collisions with atoms and molecules. Within solid state physics high intensity, high brightness e{sup +} beams are in demand in areas such as the re-emission e{sup +} microscope, two dimensional angular correlation of annihilation radiation, low energy e{sup +} diffraction and other fields. Intense e{sup +} beams are also important for the development of positronium beams, as well as exotic experiments such as Bose condensation and Ps liquid studies.

  13. Beam characteristics of energy-matched flattening filter free beams

    SciTech Connect

    Paynter, D.; Weston, S. J.; Cosgrove, V. P.; Evans, J. A.; Thwaites, D. I.

    2014-05-15

    Purpose: Flattening filter free (FFF) linear accelerators can increase treatment efficiency and plan quality. There are multiple methods of defining a FFF beam. The Elekta control system supports tuning of the delivered FFF beam energy to enable matching of the percentage depth-dose (PDD) of the flattened beam at 10 cm depth. This is compared to FFF beams where the linac control parameters are identical to those for the flattened beam. All beams were delivered on an Elekta Synergy accelerator with an Agility multi-leaf collimator installed and compared to the standard, flattened beam. The aim of this study is to compare “matched” FFF beams to both “unmatched” FFF beams and flattened beams to determine the benefits of matching beams. Methods: For the three modes of operation 6 MV flattened, 6 MV matched FFF, 6 MV unmatched FFF, 10 MV flattened, 10 MV matched FFF, and 10 MV unmatched FFF beam profiles were obtained using a plotting tank and were measured in steps of 0.1 mm in the penumbral region. Beam penumbra was defined as the distance between the 80% and 20% of the normalized dose when the inflection points of the unflattened and flattened profiles were normalized with the central axis dose of the flattened field set as 100%. PDD data was obtained at field sizes ranging from 3 cm × 3 cm to 40 cm × 40 cm. Radiation protection measurements were additionally performed to determine the head leakage and environmental monitoring through the maze and primary barriers. Results: No significant change is made to the beam penumbra for FFF beams with and without PDD matching, the maximum change in penumbra for a 10 cm × 10 cm field was within the experimental error of the study. The changes in the profile shape with increasing field size are most significant for the matched FFF beam, and both FFF beams showed less profile shape variation with increasing depth when compared to flattened beams, due to consistency in beam energy spectra across the radiation field

  14. High energy beam lifetime analysis

    SciTech Connect

    Howell, R.H.; Sterne, P.A.; Hartley, J.; Cowan, T.E.

    1997-05-01

    We have developed a positron lifetime defect analysis capability based on a 3 MeV electrostatic accelerator. The high energy beam lifetime spectrometer is operational with a 60 mCi {sup 22}Na source providing a current of 7 10{sup 5} positrons per second. Lifetime data are derived from a thin plastic transmission detector providing an implantation time and a BaF{sub 2} detector to determine the annihilation time. Positron lifetime analysis is performed with a 3 MeV positron beam on thick sample specimens at counting rates in excess of 2000 per second. The instrument is being used for bulk sample analysis and analysis of samples encapsulated in controlled environments for in situ measurements.

  15. Confined energy distribution for charged particle beams

    DOEpatents

    Jason, Andrew J.; Blind, Barbara

    1990-01-01

    A charged particle beam is formed to a relatively larger area beam which is well-contained and has a beam area which relatively uniformly deposits energy over a beam target. Linear optics receive an accelerator beam and output a first beam with a first waist defined by a relatively small size in a first dimension normal to a second dimension. Nonlinear optics, such as an octupole magnet, are located about the first waist and output a second beam having a phase-space distribution which folds the beam edges along the second dimension toward the beam core to develop a well-contained beam and a relatively uniform particle intensity across the beam core. The beam may then be expanded along the second dimension to form the uniform ribbon beam at a selected distance from the nonlinear optics. Alternately, the beam may be passed through a second set of nonlinear optics to fold the beam edges in the first dimension. The beam may then be uniformly expanded along the first and second dimensions to form a well-contained, two-dimensional beam for illuminating a two-dimensional target with a relatively uniform energy deposition.

  16. A low energy beam transport system for proton beam

    SciTech Connect

    Yang, Y.; Zhang, Z. M.; Wu, Q.; Zhang, W. H.; Ma, H. Y.; Sun, L. T.; Zhang, X. Z.; Liu, Z. W.; He, Y.; Zhao, H. W.; Xie, D. Z.

    2013-03-15

    A low energy beam transport (LEBT) system has been built for a compact pulsed hadron source (CPHS) at Tsinghua University in China. The LEBT, consisting of two solenoids and three short-drift sections, transports a pulsed proton beam of 60 mA of energy of 50 keV to the entrance of a radio frequency quadrupole (RFQ). Measurement has shown a normalized RMS beam emittance less than 0.2 {pi} mm mrad at the end of the LEBT. Beam simulations were carried out to compare with the measurement and are in good agreement. Based on the successful CPHS LEBT development, a new LEBT for a China ADS projector has been designed. The features of the new design, including a beam chopper and beam simulations of the LEBT are presented and discussed along with CPHS LEBT development in this article.

  17. Results of the 2013 UT modeling benchmark obtained with models implemented in CIVA

    SciTech Connect

    Toullelan, Gwénaël; Raillon, Raphaële; Chatillon, Sylvain; Lonne, Sébastien

    2014-02-18

    The 2013 Ultrasonic Testing (UT) modeling benchmark concerns direct echoes from side drilled holes (SDH), flat bottom holes (FBH) and corner echoes from backwall breaking artificial notches inspected with a matrix phased array probe. This communication presents the results obtained with the models implemented in the CIVA software: the pencilmodel is used to compute the field radiated by the probe, the Kirchhoff approximation is applied to predict the response of FBH and notches and the SOV (Separation Of Variables) model is used for the SDH responses. The comparison between simulated and experimental results are presented and discussed.

  18. Energy distributions in rods and beams

    NASA Technical Reports Server (NTRS)

    Wohlever, J. C.; Bernhard, R. J.

    1989-01-01

    A hypothesis proposed by Nefske and Sung (1987) that the mechanical energy flow in acoustic/structural systems can be modeled using a thermal energy flow analogy was tested for both longitudinal vibration in rods and transverse flexural vibrations in beams. It was found that the rod behaves according to the energy flow analogy. However, the beam solutions behaved significantly differently than predicted by the thermal analogy, unless spatially averaged energy and power flow were considered. Otherwise, the beam analysis is restricted to frequencies where the near-field terms in the displacement solution are negligible over most of the beam.

  19. TPX/TFTR Neutral Beam energy absorbers

    SciTech Connect

    Dahlgren, F.; Wright, K.; Kamperschroer, J.; Grisham, L.; Lontai, L.; Peters, C.; VonHalle, A.

    1993-11-01

    The present beam energy absorbing surfaces on the TFTR Neutral Beams such as Ion Dumps, Calorimeters, beam defining apertures, and scrapers, are simple water cooled copper plates which wee designed to absorb (via their thermal inertia) the incident beam power for two seconds with a five minute coal down interval between pulses. These components are not capable of absorbing the anticipated beam power loading for 1000 second TPX pulses and will have to be replaced with an actively cooled design. While several actively cooled energy absorbing designs were considered,, the hypervapotron elements currently being used on the JET beamlines were chosen due to their lower cooling water demands and reliable performance on JET.

  20. Characterization of the Abydos region through OSIRIS high-resolution images in support of CIVA measurements

    NASA Astrophysics Data System (ADS)

    Lucchetti, A.; Cremonese, G.; Jorda, L.; Poulet, F.; Bibring, J.-P.; Pajola, M.; La Forgia, F.; Massironi, M.; El-Maarry, M. R.; Oklay, N.; Sierks, H.; Barbieri, C.; Lamy, P.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J.-L.; Bertini, I.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutierrez, P. J.; Güttler, C.; Hviid, S. F.; Ip, W.-H.; Knollenberg, J.; Kramm, J.-R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Mottola, S.; Naletto, G.; Preusker, F.; Scholten, F.; Thomas, N.; Tubiana, C.; Vincent, J.-B.

    2016-01-01

    Context. On 12 November 2014, the European mission Rosetta delivered the Philae lander on the nucleus of comet 67P/Churyumov-Gerasimenko (67P). After the first touchdown, the lander bounced three times before finally landing at a site named Abydos. Aims: We provide a morphologically detailed analysis of the Abydos landing site to support Philae's measurements and to give context for the interpretation of the images coming from the Comet Infrared and Visible Analyser (CIVA) camera system onboard the lander. Methods: We used images acquired by the OSIRIS Narrow Angle Camera (NAC) on 6 December 2014 to perform the analysis of the Abydos landing site, which provided the geomorphological map, the gravitational slope map, the size-frequency distribution of the boulders. We also computed the albedo and spectral reddening maps. Results: The morphological analysis of the region could suggest that Philae is located on a primordial terrain. The Abydos site is surrounded by two layered and fractured outcrops and presents a 0.02 km2 talus deposit rich in boulders. The boulder size frequency distribution gives a cumulative power-law index of -4.0 + 0.3/-0.4, which is correlated with gravitational events triggered by sublimation and/or thermal fracturing causing regressive erosion. The average value of the albedo is 5.8% at λ1 = 480.7 nm and 7.4% at λ2 = 649.2 nm, which is similar to the global albedos derived by OSIRIS and CIVA, respectively.

  1. The NSNS High Energy Beam Transport Line

    NASA Astrophysics Data System (ADS)

    Raparia, D.; Alessi, J.; Lee, Y. Y.; Ruggiero, A. G.; Weng, W. T.

    1997-05-01

    In the NSNS design, a 160 meter long transport line connects the 1 GeV linac to an accumulator ring and provides the desired foot-print. The linac beam has a current of 56 mA and pulse length of about 1 ms. This line consists of forteen 90^circ FODO cells, and accommodates a 60^circ achromatic bend, an energy compressor, part of the injection system, and enough diagnostic devices to measure the beam quality before injection. To reduce the uncontrolled beam losses this line has four beam halo scrapers and very tight tolerances of both transverse and longitudinal beam dynamics under space charge conditions. The design of this line will be presented together with input beam parameters and acceptance criteria of the beam at the accumulator.

  2. Energy-beam-driven rapid fabrication system

    DOEpatents

    Keicher, David M.; Atwood, Clinton L.; Greene, Donald L.; Griffith, Michelle L.; Harwell, Lane D.; Jeantette, Francisco P.; Romero, Joseph A.; Schanwald, Lee P.; Schmale, David T.

    2002-01-01

    An energy beam driven rapid fabrication system, in which an energy beam strikes a growth surface to form a molten puddle thereon. Feed powder is then injected into the molten puddle from a converging flow of feed powder. A portion of the feed powder becomes incorporated into the molten puddle, forcing some of the puddle contents to freeze on the growth surface, thereby adding an additional layer of material. By scanning the energy beam and the converging flow of feed powder across the growth surface, complex three-dimensional shapes can be formed, ready or nearly ready for use. Nearly any class of material can be fabricated using this system.

  3. Tokomak disruption runaway electron beam energy deposition

    NASA Astrophysics Data System (ADS)

    Lei, Yian

    2012-10-01

    Disruption is one of the major concerns in magnetic confinement fusion (MCF) research. People believe the energetic runaway electron beam can damage the first wall by depositing most of its energy to certain region as heat, melting the wall. However, as the energy of the beam electron is very high (up to 50 MeV), most of the beam energy should be converted as gamma radiation and escape, and the fraction of thermal energy deposition is relatively small. We will calculate the runaway electron energy deposition in typical first wall configurations in ITER disruption scenario, and give the temperature profile of the wall. We will also calculate the bremsstrahlung gamma ray spectra of the beam and discuss the consequences.

  4. Low energy beam transport system developments

    NASA Astrophysics Data System (ADS)

    Dudnikov, V.; Han, B.; Stockli, M.; Welton, R.; Dudnikova, G.

    2015-04-01

    For high brightness beam production it is important to preserve the brightness in the low energy beam transport system (LEBT) used to transport and match the ion beams to the next stage of acceleration, usually an RFQ. While electrostatic focusing can be problematic for high current beam transport, reliable electrostatic LEBT operation has been demonstrated with H- beams up to 60 mA. Now, however, it is commonly accepted that an optimal LEBT for high current accelerator applications consists of focusing solenoids with space charge compensation. Two-solenoid LEBTs are successfully used for high current (>100 mA) proton beam transport. Preservation of low emittances (~0.15 π mm-mrad) requires the addition of a heavy gas (Xe, Kr), which causes ~5% of proton loss in a 1 m long LEBT. Similar Xe densities would be required to preserve low emittances of H- beams, but such gas densities cause unacceptably high H- beam losses. A short LEBT with only one short solenoid, movable for RFQ matching, can be used for reduced negative ion stripping. A strong electrostatic-focusing LEBT has been successfully adopted for transport of high current H- beams in the SNS Front End. Some modifications of such electrostatic LEBTs are expected to improve the reliable transport of intense positive and negative ion beams without greatly degrading their low emittances. We concentrate on processes that determine the beam brightness degradation and on their prevention. Proposed improvements to the SNS electrostatic LEBT are discussed.

  5. Calibration of a proton beam energy monitor

    SciTech Connect

    Moyers, M. F.; Coutrakon, G. B.; Ghebremedhin, A.; Shahnazi, K.; Koss, P.; Sanders, E.

    2007-06-15

    Delivery of therapeutic proton beams requires an absolute energy accuracy of {+-}0.64 to 0.27 MeV for patch fields and a relative energy accuracy of {+-}0.10 to 0.25 MeV for tailoring the depth dose distribution using the energy stacking technique. Achromatic switchyard tunes, which lead to better stability of the beam incident onto the patient, unfortunately limit the ability of switchyard magnet tesla meters to verify the correct beam energy within the tolerances listed above. A new monitor to measure the proton energy before each pulse is transported through the switchyard has been installed into a proton synchrotron. The purpose of this monitor is to correct and/or inhibit beam delivery when the measured beam energy is outside of the tolerances for treatment. The monitor calculates the beam energy using data from two frequency and eight beam position monitors that measure the revolution frequency of the proton bunches and the effective offset of the orbit from the nominal radius of the synchrotron. The new energy monitor has been calibrated by measuring the range of the beam through water and comparing with published range-energy tables for various energies. A relationship between depth dose curves and range-energy tables was first determined using Monte Carlo simulations of particle transport and energy deposition. To reduce the uncertainties associated with typical scanning water phantoms, a new technique was devised in which the beam energy was scanned while fixed thickness water tanks were sandwiched between two fixed parallel plate ionization chambers. Using a multitude of tank sizes, several energies were tested to determine the nominal accelerator orbit radius. After calibration, the energy reported by the control system matched the energy derived by range measurements to better than 0.72 MeV for all nine energies tested between 40 and 255 MeV with an average difference of -0.33 MeV. A study of different combinations of revolution frequency and radial

  6. Straight low energy beam transport for intense uranium beams

    NASA Astrophysics Data System (ADS)

    Xiao, C.; Groening, L.; Vormann, H.; Mickat, S.; Hollinger, R.; Adonin, A.; Orzhekhovskaya, A.; Maier, M.; Al-Omari, H.; Barth, W.; Kester, O. K.; Yaramyshev, S.

    2015-07-01

    A new high current uranium ion source and dedicated Low Energy Beam Transport (LEBT) will be built at the GSI High Current Injector (HSI). This LEBT will be integrated into the existing complex which already comprises two branches. The paper presents the design and dynamics simulation using the TRACE-3D and TRACK code. The simulation results illustrate that this straight LEBT can transport uranium beams over a wide range of space-charge compensation, and can provide 15.4 (14.2) mA U4+ inside of the effective acceptance of the subsequent RFQ assuming the space-charge is compensated to 100% (95%).

  7. Energy spectrum control for modulated proton beams

    SciTech Connect

    Hsi, Wen C.; Moyers, Michael F.; Nichiporov, Dmitri; Anferov, Vladimir; Wolanski, Mark; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E.; Schreuder, Andries N.

    2009-06-15

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to {+-}21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than {+-}3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies.

  8. High Brightness Beam Applications: Energy Recovered Linacs

    SciTech Connect

    Geoffrey A. Krafft

    2005-09-01

    In the first part of the paper some general statements are made regarding applications suitable for utilizing energy recovered linacs (ERLs) by contrasting their potential performance to that of single pass linacs and storage rings. As a result of their potential for extremely good beam quality in combination with high average beam current, ERLs have been used and considered as drivers of both free electron laser and partially coherent photon sources, from THz through X-rays; as a suitable technology for high energy electron cooling; and as a continuous or semi-continuous electron beam source for high energy colliders. At present, beam requirements tend to be highly matched to end use requirements. By reviewing some of the many examples which have either been reduced to practice, or are being explored presently, one can develop an appreciation for the wide range of parameters being considered in ERL applications.

  9. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB.

    PubMed

    Ren, Haitao; Pozdeyev, Eduard; Lund, Steven M; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn

    2016-02-01

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper. PMID:26932091

  10. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB

    NASA Astrophysics Data System (ADS)

    Ren, Haitao; Pozdeyev, Eduard; Lund, Steven M.; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn

    2016-02-01

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper.

  11. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB.

    PubMed

    Ren, Haitao; Pozdeyev, Eduard; Lund, Steven M; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn

    2016-02-01

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper.

  12. RHIC low energy beam loss projections

    SciTech Connect

    Satogata,T.

    2009-08-01

    For RHIC low-energy operations, we plan to collide Au beams with energies of E = 2:5-10 GeV/u in RHIC. Beams are injected into collision optics, and RHIC runs as a storage ring with no acceleration. At these low energies, observed beam lifetimes are minutes, with measured beam lifetimes of 3.5 min (fast) and 50 min (slow) at E=4.6 GeV/u in the March 2008 test run. With these lifetimes we can operate RHIC as a storage ring to produce reasonable integrated luminosity. This note estimates beam losses and collimator/dump energy deposition in normal injection modes of low energy operation. The main question is whether a normal injection run is feasible for an FY10 10-15 week operations run from a radiation safety perspective. A peripheral question is whether continuous injection operations is feasible from a radiation safety perspective. In continuous injection mode, we fill both rings, then continuously extract and reinject the oldest bunches that have suffered the most beam loss to increase the overall integrated luminosity. We expect to gain a factor of 2-3 in integrated luminosity from continuous injection at lowest energies if implemented[1]. Continuous injection is feasible by FY11 from an engineering perspective given enough effort, but the required extra safety controls and hardware dose risk make it unappealing for the projected luminosity improvement. Low-energy electron cooling will reduce beam losses by at least an order of magnitude vs normal low-energy operations, but low energy cooling is only feasible in the FY13 timescale and therefore beyond the scope of this note. For normal injection low energy estimates we assume the following: (1) RHIC beam total energies are E=2.5-10 GeV/u. (Continuous injection mode is probably unnecessary above total energies of E=7-8 GeV/u.); (2) RHIC operates only as a storage ring, with no acceleration; (3) 110 bunches of about 0.5-1.0 x 10{sup 9} initial bunch intensities (50-100% injection efficiency, likely conservative

  13. Beam-energy and laser beam-profile monitor at the BNL LINAC

    SciTech Connect

    Connolly, R.; Briscoe, B.; Degen, C.; DeSanto, L.; Meng, W.; Minty, M.; Nayak, S.; Raparia, D.; Russo, T.

    2010-05-02

    We are developing a non-interceptive beam profile and energy monitor for H{sup -} beams in the high energy beam transport (HEBT) line at the Brookhaven National Lab linac. Electrons that are removed from the beam ions either by laser photodetachment or stripping by background gas are deflected into a Faraday cup. The beam profile is measured by stepping a narrow laser beam across the ion beam and measuring the electron charge vs. transverse laser position. There is a grid in front of the collector that can be biased up to 125kV. The beam energy spectrum is determined by measuring the electron charge vs. grid voltage. Beam electrons have the same velocity as the beam and so have an energy of 1/1836 of the beam protons. A 200MeV H{sup -} beam yields 109keV electrons. Energy measurements can be made with either laser-stripped or gas-stripped electrons.

  14. Low energy beam transport system developments

    SciTech Connect

    Dudnikov, V.; Han, B.; Stockli, M.; Welton, R.; Dudnikova, G.

    2015-04-08

    For high brightness beam production it is important to preserve the brightness in the low energy beam transport system (LEBT) used to transport and match the ion beams to the next stage of acceleration, usually an RFQ. While electrostatic focusing can be problematic for high current beam transport, reliable electrostatic LEBT operation has been demonstrated with H{sup −} beams up to 60 mA. Now, however, it is commonly accepted that an optimal LEBT for high current accelerator applications consists of focusing solenoids with space charge compensation. Two-solenoid LEBTs are successfully used for high current (>100 mA) proton beam transport. Preservation of low emittances (~0.15 π mm-mrad) requires the addition of a heavy gas (Xe, Kr), which causes ~5% of proton loss in a 1 m long LEBT. Similar Xe densities would be required to preserve low emittances of H{sup −} beams, but such gas densities cause unacceptably high H{sup −} beam losses. A short LEBT with only one short solenoid, movable for RFQ matching, can be used for reduced negative ion stripping. A strong electrostatic-focusing LEBT has been successfully adopted for transport of high current H{sup −} beams in the SNS Front End. Some modifications of such electrostatic LEBTs are expected to improve the reliable transport of intense positive and negative ion beams without greatly degrading their low emittances. We concentrate on processes that determine the beam brightness degradation and on their prevention. Proposed improvements to the SNS electrostatic LEBT are discussed.

  15. Moving core beam energy absorber and converter

    DOEpatents

    Degtiarenko, Pavel V.

    2012-12-18

    A method and apparatus for the prevention of overheating of laser or particle beam impact zones through the use of a moving-in-the-coolant-flow arrangement for the energy absorbing core of the device. Moving of the core spreads the energy deposition in it in 1, 2, or 3 dimensions, thus increasing the effective cooling area of the device.

  16. SU-E-T-635: Quantitative Study On Beam Flatness Variation with Beam Energy Change

    SciTech Connect

    Li, J S; Eldib, A; Ma, C; Lin, M

    2014-06-15

    Purpose: Beam flatness check has been proposed for beam energy check for photon beams with flattering filters. In this work, beam flatness change with beam energy was investigated quantitatively using the Monte Carlo method and its significance was compared with depth dose curve change. Methods: Monte Carlo simulations for a linear accelerator with flattering filter were performed with different initial electron energies for photon beams of 6MV and 10MV. Dose calculations in a water phantom were then perform with the phase space files obtained from the simulations. The beam flatness was calculated based on the dose profile at 10 cm depth for all the beams with different initial electron energies. The percentage depth dose (PDD) curves were also analyzed. The dose at 10cm depth (D10) and the ratio of the dose at 10cm and 20cm depth (D10/D20) and their change with the beam energy were calculated and compared with the beam flatness variation. Results: It was found that the beam flatness variation with beam energy change was more significant than the change of D10 and the ratio between D10 and D20 for both 6MV and 10MV beams. Half MeV difference on the initial electron beam energy brought in at least 20% variation on the beam flatness but only half percent change on the ratio of D10 and D20. The change of D10 or D20 alone is even less significant. Conclusion: The beam energy impact on PDD is less significant than that on the beam flatness. If the PDD is used for checking the beam energy, uncertainties of the measurement could possibly disguise its change. Beam flatness changes more significantly with beam energy and therefore it can be used for monitoring the energy change for photon beams with flattering filters. However, other factors which may affect the beam flatness should be watched as well.

  17. Individual Beam Size And Length Measurements at the SLC Interaction Point Derived From the Beam Energy Loss During a Beam Beam Deflection Scan

    SciTech Connect

    Raimondi, P.; Field, R.Clive; Phinney, N.; Ross, M.C.; Slaton, T.; Traller, R.; /SLAC

    2011-08-26

    At the Interaction Point (IP) of the SLC Final Focus, beam-beam deflection scans routinely provide a measurement of the sum in quadrature of the electron and positron transverse beam sizes, but no information on the individual beam sizes. During the 1996 SLC run, an upgrade to the Final Focus beam position monitor system allowed a first measurement of the absolute beam energy loss of both beams on each step of the deflection scan. A fit to the energy loss distributions of the two beams provides a measurement not only of the individual transverse beam sizes at the IP but also of the individual bunch lengths.

  18. Energy Production Demonstrator for Megawatt Proton Beams

    SciTech Connect

    Pronskikh, Vitaly S.; Mokhov, Nikolai V.; Novitski, Igor; Tyutyunnikov, Sergey I.

    2014-07-16

    A preliminary study of the Energy Production Demonstrator (EPD) concept - a solid heavy metal target irradiated by GeV-range intense proton beams and producing more energy than consuming - is carried out. Neutron production, fission, energy deposition, energy gain, testing volume and helium production are simulated with the MARS15 code for tungsten, thorium, and natural uranium targets in the proton energy range 0.5 to 120 GeV. This study shows that the proton energy range of 2 to 4 GeV is optimal for both a natU EPD and the tungsten-based testing station that would be the most suitable for proton accelerator facilities. Conservative estimates, not including breeding and fission of plutonium, based on the simulations suggest that the proton beam current of 1 mA will be sufficient to produce 1 GW of thermal output power with the natU EPD while supplying < 8% of that power to operate the accelerator. The thermal analysis shows that the concept considered has a problem due to a possible core meltdown; however, a number of approaches (a beam rastering, in first place) are suggested to mitigate the issue. The efficiency of the considered EPD as a Materials Test Station (MTS) is also evaluated in this study.

  19. Beamed-Energy Propulsion (BEP) Study

    NASA Technical Reports Server (NTRS)

    George, Patrick; Beach, Raymond

    2012-01-01

    The scope of this study was to (1) review and analyze the state-of-art in beamed-energy propulsion (BEP) by identifying potential game-changing applications, (2) formulate a roadmap of technology development, and (3) identify key near-term technology demonstrations to rapidly advance elements of BEP technology to Technology Readiness Level (TRL) 6. The two major areas of interest were launching payloads and space propulsion. More generally, the study was requested and structured to address basic mission feasibility. The attraction of beamed-energy propulsion (BEP) is the potential for high specific impulse while removing the power-generation mass. The rapid advancements in high-energy beamed-power systems and optics over the past 20 years warranted a fresh look at the technology. For launching payloads, the study concluded that using BEP to propel vehicles into space is technically feasible if a commitment to develop new technologies and large investments can be made over long periods of time. From a commercial competitive standpoint, if an advantage of beamed energy for Earth-to-orbit (ETO) is to be found, it will rest with smaller, frequently launched payloads. For space propulsion, the study concluded that using beamed energy to propel vehicles from low Earth orbit to geosynchronous Earth orbit (LEO-GEO) and into deep space is definitely feasible and showed distinct advantages and greater potential over current propulsion technologies. However, this conclusion also assumes that upfront infrastructure investments and commitments to critical technologies will be made over long periods of time. The chief issue, similar to that for payloads, is high infrastructure costs.

  20. Multipass Beam Breakup in Energy Recovery Linacs

    SciTech Connect

    Eduard Pozdeyev; Christopher Tennant; Joseph Bisognano; M Sawamura; R. Hajima; T.I. Smith

    2005-03-19

    This paper is a compilation of several presentations on multipass beam breakup (BBU) in energy recovery linacs (ERL) given at the 32nd Advanced ICFA Beam Workshop on ERLs. The goal of this paper is to summarize the progress achieved in analytical, numerical, and experimental studies of the instability and outline available and proposed BBU mitigation techniques. In this paper, a simplified theory of multipass BBU in recirculating linacs is presented. Several BBU suppression techniques and their working principles are discussed. The paper presents an overview of available BBU codes. Results of experimental studies of multipass BBU at the Jefferson Laboratory (JLab) FEL Upgrade are described.

  1. One THz. Beamed Energy - Mission Capabilities

    NASA Astrophysics Data System (ADS)

    Johansen, Donald G.

    2005-04-01

    Gyrotrons now used for nuclear fusion experiments are a possibile source for beamed energy electro-thermal propulsion. Water vapor absorption is likely to bar 1 THz. transmission through the atmosphere. A space-based source in low equatorial orbit offers beamed energy velocity increments for upper stage orbit insertion. Transfer orbits to geosynchronous and lunar destinations and escape velocities to Mars and Venus are considered. Rapid acceleration (1 g) at high specific impulse implies very high source power and mass. Altitudes for BEP source satellites are in 600 to 800 kilometer range, set by atmospheric drag and avoidance of van Allen belt. Earth oblateness plus lunar and solar tidal forces are important factors governing source orbit selection and maintenance.

  2. Space Experiments to Advance Beamed Energy Propulsion

    NASA Astrophysics Data System (ADS)

    Johansen, Donald G.

    2010-05-01

    High power microwave sources are now available and usable, with modification, or beamed energy propulsion experiments in space. As output windows and vacuum seals are not needed space is a natural environment for high power vacuum tubes. Application to space therefore improves reliability and performance but complicates testing and qualification. Low power communications satellite devices (TWT, etc) have already been through the adapt-to-space design cycle and this history is a useful pathway for high power devices such as gyrotrons. In this paper, space experiments are described for low earth orbit (LEO) and lunar environment. These experiments are precursors to space application for beamed energy propulsion using high power microwaves. Power generation and storage using cryogenic systems are important elements of BEP systems and also have an important role as part of BEP experiments in the space environment.

  3. An Exploration Perspective of Beamed Energy Propulsion

    SciTech Connect

    Cole, John

    2008-04-28

    The Vision for Exploration is currently focused on flying the Space Shuttle safely to complete our Space Station obligations, retiring the Shuttle in 2010, then returning humans to the Moon and learning how to proceed to Mars and beyond. The NASA budget still includes funds for science and aeronautics but the primary focus is on human exploration. Fiscal constraints have led to pursuing exploration vehicles that use heritage hardware, particularly existing boosters and engines, with the minimum modifications necessary to satisfy mission requirements. So, pursuit of immature technologies is not currently affordable by NASA. Beamed energy is one example of an immature technology, from a human exploration perspective, that may eventually provide significant benefits for human exploration of space, but likely not in the near future. Looking to the more distant future, this paper will examine some of the criteria that must be achieved by beamed energy propulsion to eventually contribute to human exploration of the solar system. The analysis focuses on some of the implications of increasing the payload fraction of a launch vehicle, with a quick look at trans-lunar injection. As one would expect, there is potential for benefit, and there are concerns. The analysis concludes with an assessment of the Technology Readiness Level (TRL) for some beamed energy propulsion components, indicating that TRL 2 is close to being completed.

  4. An Exploration Perspective of Beamed Energy Propulsion

    NASA Technical Reports Server (NTRS)

    Cole, John W.

    2007-01-01

    The Vision for Exploration is currently focused on flying the Space Shuttle safely to complete our Space Station obligations, retiring the Shuttle in 2010, then returning humans to the Moon and learning how to proceed to Mars and beyond. The NASA budget still includes funds for science and aeronautics but the primary focus is on human exploration. Fiscal constraints have led to pursuing exploration vehicles that use heritage hardware, particularly existing boosters and engines, with the minimum modifications necessary to satisfy mission requirements. So, pursuit of immature technologies is not currently affordable by NASA. Beamed energy is one example of an immature technology, from a human exploration perspective, that may eventually provide significant benefits for human exploration of space, but likely not in the near future. Looking to the more distant future, this paper will examine some of the criteria that must be achieved by beamed energy propulsion to eventually contribute to human exploration of the solar system. The analysis focuses on some of the implications of increasing the payload fraction of a launch vehicle, with a quick look at trans-lunar injection. As one would expect, there is potential for benefit, and there are concerns. The analysis concludes with an assessment of the Technology Readiness Level (TRL) for some beamed energy propulsion components, indicating that TRL 2 is close to being completed.

  5. High energy electron beams for ceramic joining

    SciTech Connect

    Turman, B.N.; Glass, S.J.; Halbleib, J.A.; Helmich, D.R.; Loehman, R.E.; Clifford, J.R.

    1994-12-31

    Joining of structural ceramics is possible using high melting point metals such as Mo and Pt that are heated with a high energy electron beam, with the potential for high temperature joining. A 10 MeV electron beam can penetrate through 1 cm of ceramic, offering the possibility of buried interface joining. Because of transient heating and the lower heat capacity of the metal relative to the ceramic, a pulsed high power beam has the potential for melting the metal without decomposing or melting the ceramic. We have demonstrated the feasibility of the process with a series of 10 MeV, 1 kW electron beam experiments. Shear strengths up to 28 MPa have been measured. This strength is comparable to that reported in the literature for bonding silicon nitride to molybdenum with copper-silver-titanium braze, but weaker than that reported for Si{sub 3}N{sub 4}-Si{sub 3}N{sub 4} with gold-nickel braze. The bonding mechanism appears to be a thin silicide layer.

  6. Neutralizer options for high energy H/sup -/ beams

    SciTech Connect

    Fink, J.H.

    1986-10-01

    A neutralizer converts a negative ion beam into a neutral beam, but it also increases the beamline cost, weight and size while reducing its output power, efficiency and possibly the reliability of the entire system. In addition it scatters the newly formed neutrals, altering the beam current density distribution, causing the beam divergence to get larger and the brightness to go down. In the following, the role of neutralizers for hydrogen ion beams is reviewed, and the problems encountered over a range of beam energies are discussed. Consideration is given to enhancing the goals of the neutral beam application, be they the highest neutral fraction, optimum overall efficiency or maximum beam brightness, etc.

  7. Energy compensation of slow extracted beams with RF acceleration

    NASA Astrophysics Data System (ADS)

    Fujimoto, Tetsuya; Souda, Hikaru; Torikoshi, Masami; Kanai, Tatsuaki; Yamada, Satoru; Noda, Koji

    2016-03-01

    In a conventional carbon-ion radiotherapy facility, a carbon-ion beam is typically accelerated up to an optimum energy, slowly extracted from a synchrotron ring by a resonant slow extraction method, and ultimately delivered to a patient through a beam-delivery system. At Japan's Gunma University, a method employing slow-beam extraction along with beam-acceleration has been adopted. This method slightly alters the extracted-beam's energy owing to the acceleration component of the process, which subsequently results in a residual-range variation of approximately 2 mm in water-equivalent length. However, this range variation does not disturb a distal dose distribution with broad-beam methods such as the single beam-wobbling method. With the pencil-beam 3D scanning method, however, such a range variation disturbs a distal dose distribution because the variation is comparable to slice thickness. Therefore, for pencil-beam 3D scanning, an energy compensation method for a slow extracted beam is proposed in this paper. This method can compensate for the aforementioned energy variances by controlling net energy losses through a rotatable energy absorber set fixed between the synchrotron exit channel and the isocenter. Experimental results demonstrate that beam energies can be maintained constant, as originally hypothesized. Moreover, energy-absorber positions were found to be significantly enhanced by optimizing beam optics for reducing beam-size growth by implementation of the multiple-scattering effect option.

  8. Beam-beam interaction study of medium energy eRHIC

    SciTech Connect

    Hao,Y.; Litvinenko, V. N.; Ptitsyn, V.

    2009-07-15

    Medium Energy eRHIC (MeRHIC), the first stage design of eRHIC, includes a multi-pass ERL that provides 4GeV high quality electron beam to collide with the ion beam of RHIC. It delivers a minimum luminosity of 10{sup 32} cm{sup -2}s{sup -1}. Beam-beam effects present one of major factors limiting the luminosity of colliders. In this paper, both beam-beam effects on the electron beam and the proton beam in MeRHIC are investigated. The beam-beam interaction can induce a head-tail type instability of the proton beam referred to as the kink instability. Thus, beam stability conditions should be established to avoid proton beam loss. Also, the electron beam transverse disruption by collisions has to be evaluated to ensure that the beam quality is good enough for the energy recovery pass. The relation of proton beam stability, electron disruption and consequential luminosity are carried out after thorough discussion.

  9. Low-energy beam transport studies supporting the Spallation Neutron Source 1-MW beam operationa

    SciTech Connect

    Han, Baoxi; Kalvas, T.; Tarvainen, O.; Welton, Robert F; Murray Jr, S N; Pennisi, Terry R; Santana, Manuel; Stockli, Martin P

    2012-01-01

    The H- injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the Spallation Neutron Source 1-MW beam operation with ~38 mA beam current in the linac at 60 Hz with a pulse length of up to ~1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: 1) inconsistent dependence of the post-RFQ beam current on the ion source tilt angle, and 2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  10. Beam lifetime and limitations during low-energy RHIC operation

    SciTech Connect

    Fedotov, A.V.; Bai, M.; Blaskiewicz, M.; Fischer, W.; Kayran, D.; Montag, C.; Satogata, T.; Tepikian, S.; Wang, G.

    2011-03-28

    The low-energy physics program at the Relativistic Heavy Ion Collider (RHIC), motivated by a search for the QCD phase transition critical point, requires operation at low energies. At these energies, large nonlinear magnetic field errors and large beam sizes produce low beam lifetimes. A variety of beam dynamics effects such as Intrabeam Scattering (IBS), space charge and beam-beam forces also contribute. All these effects are important to understand beam lifetime limitations in RHIC at low energies. During the low-energy RHIC physics run in May-June 2010 at beam {gamma} = 6.1 and {gamma} = 4.1, gold beam lifetimes were measured for various values of space-charge tune shifts, transverse acceptance limitation by collimators, synchrotron tunes and RF voltage. This paper summarizes our observations and initial findings.

  11. Surface of the comet 67P from PHILAE/CIVA images as clues to the formation of the comet nucleus

    NASA Astrophysics Data System (ADS)

    Poulet, Francois; Bibring, Jean-Pierre; Carter, John; Eng, Pascal; Gondet, Brigitte; Jorda, Laurent; Langevin, Yves; Le Mouélic, Stéphane; Pilorget, Cédric

    2015-04-01

    The CIVA cameras onboard PHILAE provided the first ever in situ images of the surface of a comet (Bibring et al., this conf). The panorama acquired by CIVA at the landing site reveals a rough terrain dominated by agglomerates of consolidated materials similar to cm-sized pebbles. While the composition of these materials is unknown, their nature will be discussed in relation to both endogenic and exogenic processes that may sculpted the landscape of the landing site. These processes includes erosion (spatially non-uniform) by sublimation, redeposition of particles after ejection, fluidization and transport of cometary material on the surface, sintering effect, thermal fatigue, thermal stress, size segregation due to shaking, eolian erosion due to local outflow of cometary vapor and impact cratering at various scales. Recent advancements in planet formation theory suggest that the initial planetesimals (or cometestimals) may grow directly from the gravitational collapse of aerodynamically concentrated small particles, often referred to as "pebbles" (Johansen et al. 2007, Nature 448, 1022; Cuzzi et al. 2008, AJ 687, 1432). We will then discuss the possibility that the observed pebble pile structures are indicative of the formation process from which the initial nucleus formed, and how we can use this idea to learn about protoplanetary disks and the early processes involved in the Solar System formation.

  12. High Energy Polarized e+e- Beams

    NASA Astrophysics Data System (ADS)

    Shatunov, Yu.; Koop, I.; Otboev, A.; Mane, S.

    2016-02-01

    Recently, the wide discussion about Higgs-factory design again returns to problem of high energy polarized electrons and positrons. It’s good known the radiative beam polarization at LEP-collider. It was obtained after spin resonance suppression at Z0 pick, but didn’t appear at energies above 70 GeV due to an enhancement of unavoidable depolarization effects. We examine in this paper various ideas for radiative polarization at TLEP/FCC-ee and formulate some estimates for the polarization buildup time and the asymptotic polarization. Using wigglers, a useful degree of polarization (for energy calibration), with a time constant of about 1 h, may be possible up to the threshold of W pair production. At higher energies such as the threshold of Higgs production, attaining a useful level of polarization may be difficult in a planar ring. With Siberian Snakes, wigglers and some imagination, polarization of reasonable magnitude, with a reasonable time constant (of not more than about 1 h), may be achievable at very high energies.

  13. Energy Beam Highways Through the Skies

    NASA Technical Reports Server (NTRS)

    Myrabo, Leik N.

    1996-01-01

    The emergence of Energy Beam Flight Transportation Systems could dramatically change the way we travel in the 21st Century. A framework for formulating 'Highways of Light' and the top level architectures that invoke radically new Space Power Grid infrastructure, are introduced. Basically, such flight systems, hereafter called Lightcraft, would employ off-board energy beam sources (either laser or microwave) to energize on-board dependent 'motors' -- instead of the traditional autonomous 'engines' with their on-board energy sources (e.g., chemical fuels). Extreme reductions in vehicle dry mass appear feasible with the use of off-board power and a high degree of on-board artificial intelligence. Such vehicles may no longer need airports for refueling (since they require no propellant), and could possibly pick up travelers at their homes -- before motoring over to one of many local boost stations, for the flight out. With off-board power, hyper-energetic acceleration performance and boost-glide trajectories become feasible. Hypersonic MS airbreathing propulsion can enable boosts up to twice escape velocity, which will cut trip times to the moon down to 5.5 hours. The predominant technological, environmental and social factors that will result from such transportation systems will be stressed. This presentation first introduces the remote source siting options for the space power system infrastructure, and then provides three representative laser/microwave Lightcraft options (derived from historical Case Studies): i.e., 'Acorn', 'Toy Top', and 'Disc.' Next the gamut of combined-cycle engine options developed for these Lightcraft are examined -- to illuminate the 'emerging technologies' that must be harnessed to produce flight hardware. Needed proof-of concept experiments are identified, along with the Macro-Level Issues that can springboard these revolutionary concepts into hardware reality.

  14. Energy Beam Highways Through the Skies

    SciTech Connect

    Myrabo, L.N.

    1996-02-01

    The emergence of Energy Beam Flight Transportation Systems could dramatically change the way one travels in the 21st Century. A framework for formulating `Highways of Light` and the top level architectures that invoke radically new Space Power Grid infrastructure, are introduced. Basically, such flight systems, hereafter called Lightcraft, would employ off-board energy beam sources (either laser or microwave) to energize on-board dependent `motors` -- instead of the traditional autonomous `engines` with their on-board energy sources (e.g., chemical fuels). Extreme reductions in vehicle dry mass appear feasible with the use of off-board power and a high degree of on-board artificial intelligence. Such vehicles may no longer need airports for refueling (since they require no propellant), and could possibly pick up travelers at their homes -- before motoring over to one of many local boost stations, for the flight out. With off-board power, hyper-energetic acceleration performance and boost-glide trajectories become feasible. Hypersonic MS airbreathing propulsion can enable boosts up to twice escape velocity, which will cut trip times to the moon down to 5.5 hours. The predominant technological, environmental and social factors that will result from such transportation systems will be stressed. This presentation first introduces the remote source siting options for the space power system infrastructure, and then provides three representative laser/microwave Lightcraft options (derived from historical Case Studies): i.e., `Acorn`, `Toy Top`, and `Disc.` Next the gamut of combined-cycle engine options developed for these Lightcraft are examined -- to illuminate the `emerging technologies` that must be harnessed to produce flight hardware. Needed proof-of concept experiments are identified, along with the Macro-Level Issues that can springboard these revolutionary concepts into hardware reality.

  15. Use of incomplete energy recovery for the energy compression of large energy spread charged particle beams

    DOEpatents

    Douglas, David R.; Benson, Stephen V.

    2007-01-23

    A method of energy recovery for RF-base linear charged particle accelerators that allows energy recovery without large relative momentum spread of the particle beam involving first accelerating a waveform particle beam having a crest and a centroid with an injection energy E.sub.o with the centroid of the particle beam at a phase offset f.sub.o from the crest of the accelerating waveform to an energy E.sub.full and then recovering the beam energy centroid a phase f.sub.o+Df relative to the crest of the waveform particle beam such that (E.sub.full-E.sub.o)(1+cos(f.sub.o+Df))>dE/2 wherein dE=the full energy spread, dE/2=the full energy half spread and Df=the wave form phase distance.

  16. A laser-wire beam-energy and beam-profile monitor at the BNL linac

    SciTech Connect

    Connolly, R.; Degen, C.; DeSanto, L.; Meng, W.; Michnoff, R.; Minty, M.; Nayak, S.

    2011-03-28

    In 2009 a beam-energy monitor was installed in the high energy beam transport (HEBT) line at the Brookhaven National Lab linac. This device measures the energies of electrons stripped from the 40mA H{sup -} beam by background gas. Electrons are stripped by the 2.0x10{sup -7}torr residual gas at a rate of {approx}1.5x10{sup -8}/cm. Since beam electrons have the same velocities as beam protons, the beam proton energy is deduced by multiplying the electron energy by m{sub p}/m{sub e}=1836. A 183.6MeV H{sup -} beam produces 100keV electrons. In 2010 we installed an optics plates containing a laser and scanning optics to add beam-profile measurement capability via photodetachment. Our 100mJ/pulse, Q-switched laser neutralizes 70% of the beam during its 10ns pulse. This paper describes the upgrades to the detector and gives profile and energy measurements.

  17. Electron beam energy QA - a note on measurement tolerances.

    PubMed

    Meyer, Juergen; Nyflot, Matthew J; Smith, Wade P; Wottoon, Landon S; Young, Lori; Yang, Fei; Kim, Minsun; Hendrickson, Kristi R G; Ford, Eric; Kalet, Alan M; Cao, Ning; Dempsey, Claire; Sandison, George A

    2016-01-01

    Monthly QA is recommended to verify the constancy of high-energy electron beams generated for clinical use by linear accelerators. The tolerances are defined as 2%/2 mm in beam penetration according to AAPM task group report 142. The practical implementation is typically achieved by measuring the ratio of readings at two different depths, preferably near the depth of maximum dose and at the depth corresponding to half the dose maximum. Based on beam commissioning data, we show that the relationship between the ranges of energy ratios for different electron energies is highly nonlinear. We provide a formalism that translates measurement deviations in the reference ratios into change in beam penetration for electron energies for six Elekta (6-18 MeV) and eight Varian (6-22 MeV) electron beams. Experimental checks were conducted for each Elekta energy to compare calculated values with measurements, and it was shown that they are in agreement. For example, for a 6 MeV beam a deviation in the measured ionization ratio of ± 15% might still be acceptable (i.e., be within ± 2 mm), whereas for an 18 MeV beam the corresponding tolerance might be ± 6%. These values strongly depend on the initial ratio chosen. In summary, the relationship between differences of the ionization ratio and the corresponding beam energy are derived. The findings can be translated into acceptable tolerance values for monthly QA of electron beam energies. PMID:27074488

  18. Low energy ion beam dynamics of NANOGAN ECR ion source

    NASA Astrophysics Data System (ADS)

    Kumar, Sarvesh; Mandal, A.

    2016-04-01

    A new low energy ion beam facility (LEIBF) has been developed for providing the mass analyzed highly charged intense ion beams of energy ranging from a few tens of keV to a few MeV for atomic, molecular and materials sciences research. The new facility consists of an all permanent magnet 10 GHz electron cyclotron resonance (ECR) ion source (NANOGAN) installed on a high voltage platform (400 kV) which provides large currents of multiply charged ion beams. Higher emittance at low energy of intense ion beam puts a tremendous challenge to the beam optical design of this facility. The beam line consists of mainly the electrostatic quadrupoles, an accelerating section, analyzing cum switching magnet and suitable beam diagnostics including vacuum components. The accelerated ion beam is analyzed for a particular mass to charge (m/q) ratio as well as guided to three different lines along 75°, 90° and 105° using a large acceptance analyzing cum switching magnet. The details of transverse beam optics to all the beam lines with TRANSPORT and GICOSY beam optics codes are being described. Field computation code, OPERA 3D has been utilized to design the magnets and electrostatic quadrupoles. A theoretical estimation of emittance for optimized geometry of ion source is given so as to form the basis of beam optics calculations. The method of quadrupole scan of the beam is used to characterize the emittance of the final beam on the target. The measured beam emittance increases with m/q ratios of various ion beams similar to the trend observed theoretically.

  19. Acoustical problems in high energy pulsed E-beams lasers

    NASA Technical Reports Server (NTRS)

    Horton, T. E.; Wylie, K. F.

    1976-01-01

    During the pulsing of high energy, CO2, electron beam lasers, a significant fraction of input energy ultimately appears as acoustical disturbances. The magnitudes of these disturbances were quantified by computer analysis. Acoustical and shock impedance data are presented on materials (Rayleigh type) which show promise in controlling acoustical disturbance in E-beam systems.

  20. High resolution energy analyzer for broad ion beam characterization

    SciTech Connect

    Kanarov, V.; Hayes, A.; Yevtukhov, R.; Siegfried, D.; Sferlazzo, P.

    2008-09-15

    Characterization of the ion energy distribution function (IEDF) of low energy high current density ion beams by conventional retarding field and deflection type energy analyzers is limited due to finite ion beam emittance and beam space charge spreading inside the analyzer. These deficiencies are, to a large extent, overcome with the recent development of the variable-focusing retarding field energy analyzer (RFEA), which has a cylindrical focusing electrode preceding the planar retarding grid. The principal concept of this analyzer is conversion of a divergent charged particle beam into a quasiparallel beam before analyzing it by the planar retarding field. This allows analysis of the beam particle total kinetic energy distribution with greatly improved energy resolution. Whereas this concept was first applied to analyze 5-10 keV pulsed electron beams, the present authors have adapted it to analyze the energy distribution of a low energy ({<=}1 KeV) broad ion beam. In this paper we describe the RFEA design, which was modified from the original, mainly as required by the specifics of broad ion beam energy analysis, and the device experimental characterization and modeling results. Among the modifications, an orifice electrode placed in front of the RFEA provides better spatial resolution of the broad ion beam ion optics emission region and reduces the beam plasma density in the vicinity of analyzer entry. An electron repeller grid placed in front of the RFEA collector was found critical for suppressing secondary electrons, both those incoming to the collector and those released from its surface, and improved energy spectrum measurement repeatability and accuracy. The use of finer mesh single- and double-grid retarding structures reduces the retarding grid lens effect and improves the analyzer energy resolution and accuracy of the measured spectrum mean energy. However, additional analyzer component and configuration improvements did not further change the analyzed

  1. Electron beam directed energy device and methods of using same

    DOEpatents

    Retsky, Michael W.

    2007-10-16

    A method and apparatus is disclosed for an electron beam directed energy device. The device consists of an electron gun with one or more electron beams. The device includes one or more accelerating plates with holes aligned for beam passage. The plates may be flat or preferably shaped to direct each electron beam to exit the electron gun at a predetermined orientation. In one preferred application, the device is located in outer space with individual beams that are directed to focus at a distant target to be used to impact and destroy missiles. The aimings of the separate beams are designed to overcome Coulomb repulsion. A method is also presented for directing the beams to a target considering the variable terrestrial magnetic field. In another preferred application, the electron beam is directed into the ground to produce a subsurface x-ray source to locate and/or destroy buried or otherwise hidden objects including explosive devices.

  2. Absolute beam energy measurements in e+e- storage rings

    NASA Astrophysics Data System (ADS)

    Placidi, M.

    1997-01-01

    The CERN Large Electron Positron collider (LEP) was dedicated to the measurement of the mass Mz and the width Γz of the Z0 resonance during the LEP1 phase which terminated in September 1995. The Storage Ring operated in Energy Scan mode during the 1993 and 1995 physics runs by choosing the beam energy Ebeam to correspond to a center-of-mass (CM) energy at the interaction points (IPs) ECMpeak±1762 MeV. After a short review of the techniques usually adopted to set and control the beam energy, this paper describes in more detail two methods adopted at LEP for precise beam energy determination that are essential to reduce the contribution to the systematic error on Mz and Γz. The positron beam momentum was initially determined at the 20-GeV injection energy by measuring the speed of a less relativistic proton beam circulating on the same orbit, taking advantage of the unique opportunity to inject two beams into the LEP at short time intervals. The positron energy at the Z0 peak was in this case derived by extrapolation. Once transverse polarization became reproducible, the Resonant Depolarization (RD) technique was implemented at the Z0 operating energies, providing a ⩽2×10-5 instantaneous accuracy. RD Beam Energy Calibration has been adopted during the LEP Energy Scan campaigns as well as in Accelerator Physics runs for accurate measurement of machine parameters.

  3. Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation

    SciTech Connect

    Han, B. X.; Welton, R. F.; Murray, S. N. Jr.; Pennisi, T. R.; Santana, M.; Stockli, M. P.; Kalvas, T.; Tarvainen, O.

    2012-02-15

    The H{sup -} injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with {approx}38 mA beam current in the linac at 60 Hz with a pulse length of up to {approx}1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  4. Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation

    SciTech Connect

    Kalvas, T.; Welton, Robert F; Pennisi, Terry R

    2012-01-01

    The H{sup -} injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with {approx}38 mA beam current in the linac at 60 Hz with a pulse length of up to {approx}1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  5. Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation.

    PubMed

    Han, B X; Kalvas, T; Tarvainen, O; Welton, R F; Murray, S N; Pennisi, T R; Santana, M; Stockli, M P

    2012-02-01

    The H(-) injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with ∼38 mA beam current in the linac at 60 Hz with a pulse length of up to ∼1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  6. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    NASA Astrophysics Data System (ADS)

    Jang, Hyojae; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok

    2016-02-01

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  7. H- beam transport experiments in a solenoid low energy beam transport.

    PubMed

    Gabor, C; Back, J J; Faircloth, D C; Izaola, Z; Lawrie, S R; Letchford, A P

    2012-02-01

    The Front End Test Stand (FETS) is located at Rutherford Appleton Laboratory and aims for a high current, fast chopped 3 MeV H(-) ion beam suitable for future high power proton accelerators like ISIS upgrade. The main components of the front end are the Penning ion source, a low energy beam transport line, an radio-frequency quadrupole (RFQ) and a medium energy beam transport (MEBT) providing also a chopper section and rebuncher. FETS is in the stage of commissioning its low energy beam transport (LEBT) line consisting of three solenoids. The LEBT has to transport an H(-) high current beam (up to 60 mA) at 65 keV. This is the injection energy of the beam into the RFQ. The main diagnostics are slit-slit emittance scanners for each transversal plane. For optimizing the matching to the RFQ, experiments have been performed with a variety of solenoid settings to better understand the actual beam transport. Occasionally, source parameters such as extractor slit width and beam energy were varied as well. The paper also discusses simulations based on these measurements.

  8. H{sup -} beam transport experiments in a solenoid low energy beam transport

    SciTech Connect

    Gabor, C.; Back, J. J.; Faircloth, D. C.; Lawrie, S. R.; Letchford, A. P.; Izaola, Z.

    2012-02-15

    The Front End Test Stand (FETS) is located at Rutherford Appleton Laboratory and aims for a high current, fast chopped 3 MeV H{sup -} ion beam suitable for future high power proton accelerators like ISIS upgrade. The main components of the front end are the Penning ion source, a low energy beam transport line, an radio-frequency quadrupole (RFQ) and a medium energy beam transport (MEBT) providing also a chopper section and rebuncher. FETS is in the stage of commissioning its low energy beam transport (LEBT) line consisting of three solenoids. The LEBT has to transport an H{sup -} high current beam (up to 60 mA) at 65 keV. This is the injection energy of the beam into the RFQ. The main diagnostics are slit-slit emittance scanners for each transversal plane. For optimizing the matching to the RFQ, experiments have been performed with a variety of solenoid settings to better understand the actual beam transport. Occasionally, source parameters such as extractor slit width and beam energy were varied as well. The paper also discusses simulations based on these measurements.

  9. Energy transfer between laser beams crossing in ignition hohlraums

    SciTech Connect

    Michel, P; Divol, L; Williams, E A; Thomas, C A; Callahan, D A; Weber, S; Haan, S W; Salmonson, J D; Dixit, S; Hinkel, D E; Edwards, M J; MacGowan, B J; Lindl, J D; Glenzer, S H; Suter, L J

    2008-10-03

    The full scale modeling of power transfer between laser beams crossing in plasmas is presented. A new model was developed, allowing calculation of the propagation and coupling of pairs of laser beams with their associated plasma wave in three dimensions. The full laser beam smoothing techniques used in ignition experiments are modeled, and their effects on crossed-beam energy transfer is investigated. A shift in wavelength between the beams can move the instability off resonance and reduce the transfer, hence preserving the symmetry of the capsule implosion.

  10. Study on electron beam in a low energy plasma focus

    SciTech Connect

    Khan, Muhammad Zubair; Ling, Yap Seong; San, Wong Chiow

    2014-03-05

    Electron beam emission was investigated in a low energy plasma focus device (2.2 kJ) using copper hollow anode. Faraday cup was used to estimate the energy of the electron beam. XR100CR X-ray spectrometer was used to explore the impact of the electron beam on the target observed from top-on and side-on position. Experiments were carried out at optimized pressure of argon gas. The impact of electron beam is exceptionally notable with two different approaches using lead target inside hollow anode in our plasma focus device.

  11. Linac4 low energy beam measurements with negative hydrogen ions

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

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

  12. Linac4 low energy beam measurements with negative hydrogen ions

    SciTech Connect

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

    2014-02-15

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

  13. Linac4 low energy beam measurements with negative hydrogen ions.

    PubMed

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

    2014-02-01

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

  14. Piezoelectric energy harvester having planform-tapered interdigitated beams

    DOEpatents

    Kellogg, Rick A.; Sumali, Hartono

    2011-05-24

    Embodiments of energy harvesters have a plurality of piezoelectric planform-tapered, interdigitated cantilevered beams anchored to a common frame. The plurality of beams can be arranged as two or more sets of beams with each set sharing a common sense mass affixed to their free ends. Each set thus defined being capable of motion independent of any other set of beams. Each beam can comprise a unimorph or bimorph piezoelectric configuration bonded to a conductive or non-conductive supporting layer and provided with electrical contacts to the active piezoelectric elements for collecting strain induced charge (i.e. energy). The beams are planform tapered along the entirety or a portion of their length thereby increasing the effective stress level and power output of each piezoelectric element, and are interdigitated by sets to increase the power output per unit volume of a harvester thus produced.

  15. Australian Science and Technology with Relevance to Beamed Energy Propulsion

    SciTech Connect

    Froning, H. David Jr

    2008-04-28

    Although Australia has no Beamed Energy Propulsion programs at the present time, it is accomplishing significant scientific and technological activity that is of potential relevance to Beamed Energy Propulsion (BEP). These activities include: continual upgrading and enhancement of the Woomera Test Facility, Which is ideal for development and test of high power laser or microwave systems and the flight vehicles they would propel; collaborative development and test, with the US and UK of hypersonic missiles that embody many features needed by beam-propelled flight vehicles; hypersonic air breathing propulsion systems that embody inlet-engine-nozzle features needed for beam-riding agility by air breathing craft; and research on specially conditioned EM fields that could reduce beamed energy lost during atmospheric propagation.

  16. Low energy electron magnetometer using a monoenergetic electron beam

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Wood, G. M.; Rayborn, G. H.; White, F. A. (Inventor)

    1983-01-01

    A low energy electron beam magnetometer utilizes near-monoenergetic electrons thereby reducing errors due to electron energy spread and electron nonuniform angular distribution. In a first embodiment, atoms in an atomic beam of an inert gas are excited to a Rydberg state and then electrons of near zero energy are detached from the Rydberg atoms. The near zero energy electrons are then accelerated by an electric field V(acc) to form the electron beam. In a second embodiment, a filament emits electrons into an electrostatic analyzer which selects electrons at a predetermined energy level within a very narrow range. These selected electrons make up the electron beam that is subjected to the magnetic field being measured.

  17. A compact, versatile low-energy electron beam ion source

    SciTech Connect

    Zschornack, G.; König, J.; Schmidt, M.; Thorn, A.

    2014-02-15

    A new compact Electron Beam Ion Source, the Dresden EBIT-LE, is introduced as an ion source working at low electron beam energies. The EBIT-LE operates at an electron energy ranging from 100 eV to some keV and can easily be modified to an EBIT also working at higher electron beam energies of up to 15 keV. We show that, depending on the electron beam energy, electron beam currents from a few mA in the low-energy regime up to about 40 mA in the high-energy regime are possible. Technical solutions as well as first experimental results of the EBIT-LE are presented. In ion extraction experiments, a stable production of low and intermediate charged ions at electron beam energies below 2 keV is demonstrated. Furthermore, X-ray spectroscopy measurements confirm the possibility of using the machine as a source of X-rays from ions excited at low electron energies.

  18. Beam energy tracking system on Optima XEx high energy ion implanter

    SciTech Connect

    David, Jonathan; Satoh, Shu; Wu Xiangyang; Geary, Cindy; Deluca, James

    2012-11-06

    The Axcelis Optima XEx high energy implanter is an RF linac-based implanter with 12 RF resonators for beam acceleration. Even though each acceleration field is an alternating, sinusoidal RF field, the well known phase-focusing principle produces a beam with a sharp quasi-monoenergetic energy spectrum. A magnetic energy filter after the linac further attenuates the low energy continuum in the energy spectrum often associated with RF acceleration. The final beam energy is a function of the phase and amplitude of the 12 resonators in the linac. When tuning a beam, the magnetic energy filter is set to the desired energy, and each linac parameter is tuned to maximize the transmission through the filter. Once a beam is set up, all the parameters are stored in a recipe, which can be easily tuned and has proven to be quite repeatable. The magnetic field setting of the energy filter selects the beam energy from the RF Linac accelerator, and in-situ verification of beam energy in addition to the magnetic energy filter setting has long been desired. An independent energy tracking system was developed for this purpose, using the existing electrostatic beam scanner as a deflector to construct an in-situ electrostatic energy analyzer. This paper will describe the system and performance of the beam energy tracking system.

  19. The Low-Energy State ofCirculating Stored Ion Beams: Crystalline Beams

    SciTech Connect

    Wei, J.; Li, X.-P.; Sessler, Andrew M.

    1994-03-10

    Molecular dynamics is employed to study the low energy states of a beam of charged particles subject to circumferentially varying guiding and focusing forces and with Coulomb forces between the particles. In a constant gradient ring, the lowest energy state is never ordered, but in an alternating gradient structure, operating below the transition energy, the lowest state is ordered. The nature and characteristics of the ground state depends upon the beam density and the ring parameters. For zero temperature the crystal remains intact for a very long time, but at nonzero temperatures it gains energy from the lattice. A critical temperature exists above which the crystal melts rapidly.

  20. An online, energy-resolving beam profile detector for laser-driven proton beams.

    PubMed

    Metzkes, J; Zeil, K; Kraft, S D; Karsch, L; Sobiella, M; Rehwald, M; Obst, L; Schlenvoigt, H-P; Schramm, U

    2016-08-01

    In this paper, a scintillator-based online beam profile detector for the characterization of laser-driven proton beams is presented. Using a pixelated matrix with varying absorber thicknesses, the proton beam is spatially resolved in two dimensions and simultaneously energy-resolved. A thin plastic scintillator placed behind the absorber and read out by a CCD camera is used as the active detector material. The spatial detector resolution reaches down to ∼4 mm and the detector can resolve proton beam profiles for up to 9 proton threshold energies. With these detector design parameters, the spatial characteristics of the proton distribution and its cut-off energy can be analyzed online and on-shot under vacuum conditions. The paper discusses the detector design, its characterization and calibration at a conventional proton source, as well as the first detector application at a laser-driven proton source. PMID:27587116

  1. An online, energy-resolving beam profile detector for laser-driven proton beams

    NASA Astrophysics Data System (ADS)

    Metzkes, J.; Zeil, K.; Kraft, S. D.; Karsch, L.; Sobiella, M.; Rehwald, M.; Obst, L.; Schlenvoigt, H.-P.; Schramm, U.

    2016-08-01

    In this paper, a scintillator-based online beam profile detector for the characterization of laser-driven proton beams is presented. Using a pixelated matrix with varying absorber thicknesses, the proton beam is spatially resolved in two dimensions and simultaneously energy-resolved. A thin plastic scintillator placed behind the absorber and read out by a CCD camera is used as the active detector material. The spatial detector resolution reaches down to ˜4 mm and the detector can resolve proton beam profiles for up to 9 proton threshold energies. With these detector design parameters, the spatial characteristics of the proton distribution and its cut-off energy can be analyzed online and on-shot under vacuum conditions. The paper discusses the detector design, its characterization and calibration at a conventional proton source, as well as the first detector application at a laser-driven proton source.

  2. Micro-beam friction liner and method of transferring energy

    DOEpatents

    Mentesana, Charles

    2007-07-17

    A micro-beam friction liner adapted to increase performance and efficiency and reduce wear in a piezoelectric motor or actuator or other device using a traveling or standing wave to transfer energy in the form of torque and momentum. The micro-beam friction liner comprises a dense array of micro-beam projections having first ends fixed relative to a rotor and second ends projecting substantially toward a plurality of teeth of a stator, wherein the micro-beam projections are compressed and bent during piezoelectric movement of the stator teeth, thereby storing the energy, and then react against the stator teeth to convert the stored energy stored to rotational energy in the rotor.

  3. Method and apparatus for varying accelerator beam output energy

    DOEpatents

    Young, Lloyd M.

    1998-01-01

    A coupled cavity accelerator (CCA) accelerates a charged particle beam with rf energy from a rf source. An input accelerating cavity receives the charged particle beam and an output accelerating cavity outputs the charged particle beam at an increased energy. Intermediate accelerating cavities connect the input and the output accelerating cavities to accelerate the charged particle beam. A plurality of tunable coupling cavities are arranged so that each one of the tunable coupling cavities respectively connect an adjacent pair of the input, output, and intermediate accelerating cavities to transfer the rf energy along the accelerating cavities. An output tunable coupling cavity can be detuned to variably change the phase of the rf energy reflected from the output coupling cavity so that regions of the accelerator can be selectively turned off when one of the intermediate tunable coupling cavities is also detuned.

  4. Design study of low-energy beam transport for multi-charge beams at RAON

    NASA Astrophysics Data System (ADS)

    Bahng, Jungbae; Qiang, Ji; Kim, Eun-San

    2015-12-01

    The Rare isotope Accelerator Of Newness (RAON) at the Rare Isotope Science Project (RISP) is being designed to simultaneously accelerate beams with multiple charge states. It includes a driver superconducting (SC) linac for producing 200 MeV/u and 400 kW continuous wave (CW) heavy ion beams from protons to uranium. The RAON consists of a few electron cyclotron resonance ion sources, a low-energy beam transport (LEBT) system, a CW 81.25 MHz, 500 keV/u radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport system, the SC linac, and a charge-stripper system. The LEBT system for the RISP accelerator facility consists of a high-voltage platform, two 90° dipoles, a multi-harmonic buncher (MHB), solenoids, electrostatic quadrupoles, a velocity equalizer, and a diagnostic system. The ECR ion sources are located on a high-voltage platform to reach an initial beam energy of 10 keV/u. After extraction, the ion beam is transported through the LEBT system to the RFQ accelerator. The generated charge states are selected by an achromatic bending system and then bunched by the MHB in the LEBT system. The MHB is used to achieve a small longitudinal emittance in the RFQ by generating a sawtooth wave with three harmonics. In this paper, we present the results and issues of the beam dynamics of the LEBT system.

  5. Diagnostics for ion beam driven high energy density physics experiments

    SciTech Connect

    Bieniosek, F. M.; Henestroza, E.; Lidia, S.; Ni, P. A.

    2010-10-15

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K{sup +} beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  6. Diagnostics for ion beam driven high energy density physics experiments.

    PubMed

    Bieniosek, F M; Henestroza, E; Lidia, S; Ni, P A

    2010-10-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K(+) beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  7. Diagnostics for ion beam driven high energy density physics experiments.

    PubMed

    Bieniosek, F M; Henestroza, E; Lidia, S; Ni, P A

    2010-10-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K(+) beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II. PMID:21033977

  8. DIAGNOSTICS FOR ION BEAM DRIVEN HIGH ENERGY DENSITY PHYSICS EXPERIMENTS

    SciTech Connect

    Bieniosek, F.M.; Henestroza, E.; Lidia, S.; Ni, P.A.

    2010-01-04

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30-mA K{sup +} beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (VISAR), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  9. Energy Spread of the Proton Beam in the Fermilab Booster at its Injection Energy

    SciTech Connect

    Bhat, C. M.; Chase, B. E.; Chaurize, S. J.; Garcia, F. G.; Seiya, K.; Pellico, W. A.; Sullivan, T. M.; Triplett, A. K.

    2015-04-27

    We have measured the energy spread of the Booster beam at its injection energy of 400 MeV by three different methods: (1) creating a notch of about 40 nsec wide in the beam immediately after multiple turn injection and measuring the slippage time required for high and low momentum particles for a grazing touch in line-charge distribution, (2) injecting partial turn beam and letting it to debunch, and (3) comparing the beam profile monitor data with predictions from MAD simulations for the 400 MeV injection beam line. The measurements are repeated under varieties of conditions of rf systems in the ring and in the beam transfer line.

  10. Laser-based profile and energy monitor for H beams

    SciTech Connect

    Connolly,R.; Alessi, J.; Bellavia, S.; Dawson, C.; Degen, C.; Meng, W.; Raparia, D.; Russo, T.; Tsoupas, N.

    2008-09-29

    A beam profile and energy monitor for H{sup -} beams based on laser photoneutralization was built at Brookhaven National Laboratory (BNL)* for use on the High Intensity Neutrino Source (HMS) at Fermilab. An H{sup -} ion has a first ionization potential of 0.75eV and can be neutralized by light from a Nd:YAG laser ({lambda}=1064nm). To measure beam profiles, a narrow laser beam is stepped across the ion beam, removing electrons from the portion of the H{sup -} beam intercepted by the laser. These electrons are channeled into a Faraday cup by a curved axial magnetic field. To measure the energy distribution of the electrons, the laser position is fixed and the voltage on a screen in front of the Faraday cup is raised in small steps. We present a model which reproduces the measured energy spectrum from calculated beam energy and space-charge fields. Measurements are reported from experiments in the BNL linac MEBT at 750keV.

  11. Coherent parasitic energy loss of the recycler beam

    SciTech Connect

    K.Y. Ng

    2004-07-14

    Parasitic energy loss of the particle beam in the Recycler Ring is discussed. The long beam confined between two barrier waves has a spectrum that falls off rapidly with frequency. Discrete summation over the revolution harmonics must be made to obtain the correct energy loss per particle per turn, because only a few lower revolution harmonics of real part of the longitudinal impedance contribute to the parasitic energy loss. The longitudinal impedances of the broadband rf cavities, the broadband resistive-wall monitors, and the resistive wall of the vacuum chamber are discussed. They are the main sources of the parasitic energy loss.

  12. Energy measurement of electron beams by Compton scattering

    NASA Technical Reports Server (NTRS)

    Keppel, Cynthia

    1995-01-01

    A method has been proposed to utilize the well-known Compton scattering process as a tool to measure the centroid energy of a high energy electron beam at the 0.01% level. It is suggested to use the Compton scattering of an infrared laser off the electron beam, and then to measure the energy of the scattered gamma-rays very precisely using solid-state detectors. The technique proposed is applicable for electron beams with energies from 200 MeV to 16 GeV using presently available lasers. This technique was judged to be the most viable of all those proposed for beam energy measurements at the nearby Continuous Electron Beam Accelerator Facility (CEBAF). Plans for a prototype test of the technique are underway, where the main issues are the possible photon backgrounds associated with an electron accelerator and the electron and laser beam stabilities and diagnostics. The bulk of my ASEE summer research has been spent utilizing the expertise of the staff at the Aerospace Electronics Systems Division at LaRC to assist in the design of the test. Investigations were made regarding window and mirror transmission and radiation damage issues, remote movement of elements in ultra-high vacuum conditions, etc. The prototype test of the proposed laser backscattering method is planned for this December.

  13. Ion energy distribution near a plasma meniscus with beam extraction for multi element focused ion beams

    SciTech Connect

    Mathew, Jose V.; Paul, Samit; Bhattacharjee, Sudeep

    2010-05-15

    An earlier study of the axial ion energy distribution in the extraction region (plasma meniscus) of a compact microwave plasma ion source showed that the axial ion energy spread near the meniscus is small ({approx}5 eV) and comparable to that of a liquid metal ion source, making it a promising candidate for focused ion beam (FIB) applications [J. V. Mathew and S. Bhattacharjee, J. Appl. Phys. 105, 96101 (2009)]. In the present work we have investigated the radial ion energy distribution (IED) under the influence of beam extraction. Initially a single Einzel lens system has been used for beam extraction with potentials up to -6 kV for obtaining parallel beams. In situ measurements of IED with extraction voltages upto -5 kV indicates that beam extraction has a weak influence on the energy spread ({+-}0.5 eV) which is of significance from the point of view of FIB applications. It is found that by reducing the geometrical acceptance angle at the ion energy analyzer probe, close to unidirectional distribution can be obtained with a spread that is smaller by at least 1 eV.

  14. Energy harvesting from controlled buckling of piezoelectric beams

    NASA Astrophysics Data System (ADS)

    Ansari, M. H.; Karami, M. Amin

    2015-11-01

    A piezoelectric vibration energy harvester is presented that can generate electricity from the weight of passing cars or crowds. The energy harvester consists of a piezoelectric beam, which buckles when the device is stepped on. The energy harvester can have a horizontal or vertical configuration. In the vertical (direct) configuration, the piezoelectric beam is vertical and directly sustains the weight of the vehicles or people. In the horizontal (indirect) configuration, the vertical weight is transferred to a horizontal axial force through a scissor-like mechanism. Buckling of the beam results in significant stresses and, thus, large power production. However, if the beam’s buckling is not controlled, the beam will fracture. To prevent this, the axial deformation is constrained to limit the deformations of the beam. In this paper, the energy harvester is analytically modeled. The considered piezoelectric beam is a general non-uniform beam. The natural frequencies, mode shapes, and the critical buckling force corresponding to each mode shape are calculated. The electro-mechanical coupling and the geometric nonlinearities are included in the model. The design criteria for the device are discussed. It is demonstrated that a device, realized with commonly used piezoelectric patches, can generate tens of milliwatts of power from passing car traffic. The proposed device could also be implemented in the sidewalks or integrated in shoe soles for energy generation. One of the key features of the device is its frequency up-conversion characteristics. The piezoelectric beam undergoes free vibrations each time the weight is applied to or removed from the energy harvester. The frequency of the free vibrations is orders of magnitude larger than the frequency of the load. The device is, thus, both efficient and insensitive to the frequency of the force excitations.

  15. Simulating Intense Ion Beams for Inertial Fusion Energy

    SciTech Connect

    Friedman, A

    2001-02-20

    The Heavy Ion Fusion (HIF) program's goal is the development of the body of knowledge needed for Inertial Fusion Energy (IFE) to realize its promise. The intense ion beams that will drive HIF targets are nonneutral plasmas and exhibit collective, nonlinear dynamics which must be understood using the kinetic models of plasma physics. This beam physics is both rich and subtle: a wide range in spatial and temporal scales is involved, and effects associated with both instabilities and non-ideal processes must be understood. Ion beams have a ''long memory'', and initialization of a beam at mid-system with an idealized particle distribution introduces uncertainties; thus, it will be crucial to develop, and to extensively use, an integrated and detailed ''source-to-target'' HIF beam simulation capability. We begin with an overview of major issues.

  16. Simulating Intense Ion Beams for Inertial Fusion Energy

    SciTech Connect

    Friedman, A.

    2001-02-20

    The Heavy Ion Fusion (HIF) program's goal is the development of the body of knowledge needed for Inertial Fusion Energy (IFE) to realize its promise. The intense ion beams that will drive HIF targets are rzonneutral plasmas and exhibit collective, nonlinear dynamics which must be understood using the kinetic models of plasma physics. This beam physics is both rich and subtle: a wide range in spatial and temporal scales is involved, and effects associated with both instabilities and non-ideal processes must be understood. Ion beams have a ''long memory,'' and initialization of a beam at mid-system with an idealized particle distribution introduces uncertainties; thus, it will be crucial to develop, and to extensively use, an integrated and detailed ''source-to-target'' HIF beam simulation capability. We begin with an overview of major issues.

  17. Physics opportunities with higher energy pion beams

    SciTech Connect

    Dover, C.B.

    1992-12-01

    We provide a preview of the physics issues which could be addressed with intense beams of pions in the 1--2 GeV/c region. These include: the exploitation of the ({pi}{sup +}, K{sup +}) associated production reaction on proton and nuclear targets for high resolution studies of hypernuclear structure and decays, as well as {Lambda}-proton scattering, the use of pion reactions with hydrogen or deuterium targets to provide tagged {eta} beams for studies of rare decays, precision studies of baryon resonances which couple to the {pi}N system, and the exploration of pion elastic, inelastic, and charge exchange reactions above the (3,3)-resonance as a tool for the study of nuclear structure.

  18. Physics opportunities with higher energy pion beams

    SciTech Connect

    Dover, C.B.

    1992-12-01

    We provide a preview of the physics issues which could be addressed with intense beams of pions in the 1--2 GeV/c region. These include: the exploitation of the ([pi][sup +], K[sup +]) associated production reaction on proton and nuclear targets for high resolution studies of hypernuclear structure and decays, as well as [Lambda]-proton scattering, the use of pion reactions with hydrogen or deuterium targets to provide tagged [eta] beams for studies of rare decays, precision studies of baryon resonances which couple to the [pi]N system, and the exploration of pion elastic, inelastic, and charge exchange reactions above the (3,3)-resonance as a tool for the study of nuclear structure.

  19. Using Polarimetry to Determine the CEBAF Beam Energy

    SciTech Connect

    Higinbotham, Douglas W.

    2014-06-01

    As Jefferson Lab begins operations with its upgraded CEBAF a ccelerator, the lab once again needs to experimentally determine the absolute beam energy of the machine. Previously, the CE- BAF beam energy was determined using precision measurement s of the bending magnet integral fields along with beam position information. The result obta ined from this technique was cross- checked with elastic scattering from hydrogen where knowle dge of the scattering angles of the electron and proton allow the beam energy to be determined. Wh ile the field integral method will still work with the upgraded machine, the elastic cross sect ion becomes too small to make preci- sion measurements at angles that are large enough to be easil y accessible; thus a new technique for energy determination has been sought. It will be shown th at by making use of polarimetry, one can use CEBAF’s polarized electrons’ g-2 spin precessio n to determine the absolute beam energy. This can be done in a single hall if the parameters of t he machine, such as the injector energy and linac imbalance, are known or with two halls witho ut any knowledge of the machine parameters

  20. Ion energy distribution functions of low energy beams formed by wire extraction electrodes

    SciTech Connect

    Tokumura, S.; Kasuya, T.; Vasquez, M. Jr.; Maeno, S.; Wada, M.

    2012-02-15

    The two-electrode extractor system made of 0.1 mm diameter tungsten wires separated by 0.7 mm has formed an argon ion beam with 50 V extraction potential. Energy spreads of the extracted beams were typically less than 2 eV when the beam current density was low. The beam intensity rapidly decreased as the distance between the extractor and the beam detector increased, indicating space charge limited transport of the beam. Problems associated with the emittance measurements are also discussed.

  1. Crossed-beam energy transfer in direct-drive implosions

    SciTech Connect

    Seka, W; Edgell, D H; Michel, D T; Froula, D H; Goncharov, V N; Craxton, R S; Divol, L; Epstein, R; Follett, R; Kelly, J H; Kosc, T Z; Maximov, A V; McCrory, R L; Meyerhofer, D D; Michel, P; Myatt, J F; Sangster, T C; Shvydky, A; Skupsky, S; Stoeckl, C

    2012-05-22

    Direct-drive-implosion experiments on the OMEGA laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have showed discrepancies between simulations of the scattered (non-absorbed) light levels and measured ones that indicate the presence of a mechanism that reduces laser coupling efficiency by 10%-20%. This appears to be due to crossed-beam energy transfer (CBET) that involves electromagnetic-seeded, low-gain stimulated Brillouin scattering. CBET scatters energy from the central portion of the incoming light beam to outgoing light, reducing the laser absorption and hydrodynamic efficiency of implosions. One-dimensional hydrodynamic simulations including CBET show good agreement with all observables in implosion experiments on OMEGA. Three strategies to mitigate CBET and improve laser coupling are considered: the use of narrow beams, multicolor lasers, and higher-Z ablators. Experiments on OMEGA using narrow beams have demonstrated improvements in implosion performance.

  2. Low-Energy Electron Beam Direct Writing Equipment

    NASA Astrophysics Data System (ADS)

    Fuse, Takashi; Ando, Atsushi; Kotsugi, Tadashi; Kinoshita, Hidetoshi; Sugihara, Kazuyoshi

    2007-09-01

    We proposed an electron beam direct writing (EBDW) system capable of high throughput and maskless operation based on a novel concept of using both low-energy electron beam (EB) and character projection (CP) system. We fabricated an EB optical column of low-energy EBDW equipment and obtained a resist pattern. We also investigated the beam blur and line width roughness (LWR) of lines and spaces (L/S) formed on a resist to change various EB current densities and convergence half angles. The obtained results show that a Coulomb interaction effect markedly affects the beam blur in our EB optical column. Thus, we reduce the number of sources caused by LWR and developed photoresists to obtain small LWR L/S patterns for achieving a high throughput.

  3. Optimization of solenoid based low energy beam transport line for high current H+ beams

    NASA Astrophysics Data System (ADS)

    Pande, R.; Singh, P.; Rao, S. V. L. S.; Roy, S.; Krishnagopal, S.

    2015-02-01

    A 20 MeV, 30 mA CW proton linac is being developed at BARC, Mumbai. This linac will consist of an ECR ion source followed by a Radio Frequency Quadrupole (RFQ) and Drift tube Linac (DTL). The low energy beam transport (LEBT) line is used to match the beam from the ion source to the RFQ with minimum beam loss and increase in emittance. The LEBT is also used to eliminate the unwanted ions like H2+ and H3+ from entering the RFQ. In addition, space charge compensation is required for transportation of such high beam currents. All this requires careful design and optimization. Detailed beam dynamics simulations have been done to optimize the design of the LEBT using the Particle-in-cell code TRACEWIN. We find that with careful optimization it is possible to transport a 30 mA CW proton beam through the LEBT with 100% transmission and minimal emittance blow up, while at the same time suppressing unwanted species H2+ and H3+ to less than 3.3% of the total beam current.

  4. Energy gain and spectral tailoring of ion beams using ultra-high intensity laser beams

    NASA Astrophysics Data System (ADS)

    Prasad, Rajendra; Swantusch, Marco; Cerchez, Mirela; Spickermann, Sven; Auorand, Bastian; Wowra, Thomas; Boeker, Juergen; Willi, Oswald

    2015-11-01

    The field of laser driven ion acceleration over the past decade has produced a huge amount of research. Nowadays, several multi-beam facilities with high rep rate system, e.g. ELI, are being developed across the world for different kinds of experiments. The study of interaction dynamics of multiple beams possessing ultra-high intensity and ultra-short pulse duration is of vital importance. Here, we present the first experimental results on ion acceleration using two ultra-high intensity beams. Thanks to the unique capability of Arcturus laser at HHU Düsseldorf, two almost identical, independent beams in laser parameters such as intensity (>1020 W/cm2), pulse duration (30 fs) and contrast (>1010), could be accessed. Both beams are focused onto a 5 μm thin Ti target. While ensuring spatial overlap of the two beams, at relative temporal delay of ~ 50 ps (optimum delay), the proton and carbon ion energies were enhanced by factor of 1.5. Moreover, strong modulation in C4+ions near the high energy cut-off is observed later than the optimum delay for the proton enhancement. This offers controlled tailoring of the spectral content of heavy ions.

  5. Low energy, high power hydrogen neutral beam for plasma heating

    SciTech Connect

    Deichuli, P.; Davydenko, V.; Ivanov, A. Mishagin, V.; Sorokin, A.; Stupishin, N.; Korepanov, S.; Smirnov, A.

    2015-11-15

    A high power, relatively low energy neutral beam injector was developed to upgrade of the neutral beam system of the gas dynamic trap device and C2-U experiment. The ion source of the injector produces a proton beam with the particle energy of 15 keV, current of up to 175 A, and pulse duration of a few milliseconds. The plasma emitter of the ion source is produced by superimposing highly ionized plasma jets from an array of four arc-discharge plasma generators. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase the efficiency and improve the uniformity of the plasma emitter. Multi-slit grids with 48% transparency are fabricated from bronze plates, which are spherically shaped to provide geometrical beam focusing. The focal length of the Ion Optical System (IOS) is 3.5 m and the initial beam diameter is 34 cm. The IOS geometry and grid potentials were optimized numerically to ensure accurate beam formation. The measured angular divergences of the beam are ±0.01 rad parallel to the slits and ±0.03 rad in the transverse direction.

  6. Low energy, high power hydrogen neutral beam for plasma heating.

    PubMed

    Deichuli, P; Davydenko, V; Ivanov, A; Korepanov, S; Mishagin, V; Smirnov, A; Sorokin, A; Stupishin, N

    2015-11-01

    A high power, relatively low energy neutral beam injector was developed to upgrade of the neutral beam system of the gas dynamic trap device and C2-U experiment. The ion source of the injector produces a proton beam with the particle energy of 15 keV, current of up to 175 A, and pulse duration of a few milliseconds. The plasma emitter of the ion source is produced by superimposing highly ionized plasma jets from an array of four arc-discharge plasma generators. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase the efficiency and improve the uniformity of the plasma emitter. Multi-slit grids with 48% transparency are fabricated from bronze plates, which are spherically shaped to provide geometrical beam focusing. The focal length of the Ion Optical System (IOS) is 3.5 m and the initial beam diameter is 34 cm. The IOS geometry and grid potentials were optimized numerically to ensure accurate beam formation. The measured angular divergences of the beam are ±0.01 rad parallel to the slits and ±0.03 rad in the transverse direction.

  7. Low energy, high power hydrogen neutral beam for plasma heating

    NASA Astrophysics Data System (ADS)

    Deichuli, P.; Davydenko, V.; Ivanov, A.; Korepanov, S.; Mishagin, V.; Smirnov, A.; Sorokin, A.; Stupishin, N.

    2015-11-01

    A high power, relatively low energy neutral beam injector was developed to upgrade of the neutral beam system of the gas dynamic trap device and C2-U experiment. The ion source of the injector produces a proton beam with the particle energy of 15 keV, current of up to 175 A, and pulse duration of a few milliseconds. The plasma emitter of the ion source is produced by superimposing highly ionized plasma jets from an array of four arc-discharge plasma generators. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase the efficiency and improve the uniformity of the plasma emitter. Multi-slit grids with 48% transparency are fabricated from bronze plates, which are spherically shaped to provide geometrical beam focusing. The focal length of the Ion Optical System (IOS) is 3.5 m and the initial beam diameter is 34 cm. The IOS geometry and grid potentials were optimized numerically to ensure accurate beam formation. The measured angular divergences of the beam are ±0.01 rad parallel to the slits and ±0.03 rad in the transverse direction.

  8. Pin diode calibration - beam overlap monitoring for low energy cooling

    SciTech Connect

    Drees, A.; Montag, C.; Thieberger, P.

    2015-09-30

    We were trying to address the question whether or not the Pin Diodes, currently installed approximately 1 meter downstream of the RHIC primary collimators, are suitable to monitor a recombination signal from the future RHIC low energy cooling section. A maximized recombination signal, with the Au+78 ions being lost on the collimator, will indicate optimal Au-electron beam overlap as well as velocity matching of the electron beam in the cooling section.

  9. Dependence of bunch energy loss in cavities on beam velocity

    NASA Astrophysics Data System (ADS)

    Kurennoy, Sergey S.

    1999-03-01

    Beam energy loss in a cavity can be easily computed for a relativistic bunch using time-domain codes like MAFIA or ABCI. However, for nonrelativistic beams the problem is more complicated because of difficulties with its numerical formulation in the time domain. We calculate the cavity loss factors for a bunch in frequency domain as a function of its velocity and compare results with the relativistic case.

  10. Beamed-Energy Propulsion (BEP): Considerations for Beaming High Energy-Density Electromagnetic Waves Through the Atmosphere

    NASA Technical Reports Server (NTRS)

    Manning, Robert M.

    2015-01-01

    A study to determine the feasibility of employing beamed electromagnetic energy for vehicle propulsion within and outside the Earth's atmosphere was co-funded by NASA and the Defense Advanced Research Projects Agency that began in June 2010 and culminated in a Summary Presentation in April 2011. A detailed report entitled "Beamed-Energy Propulsion (BEP) Study" appeared in February 2012 as NASA/TM-2012-217014. Of the very many nuances of this subject that were addressed in this report, the effects of transferring the required high energy-density electromagnetic fields through the atmosphere were discussed. However, due to the limitations of the length of the report, only a summary of the results of the detailed analyses were able to be included. It is the intent of the present work to make available the complete analytical modeling work that was done for the BEP project with regard to electromagnetic wave propagation issues. In particular, the present technical memorandum contains two documents that were prepared in 2011. The first one, entitled "Effects of Beaming Energy Through the Atmosphere" contains an overview of the analysis of the nonlinear problem inherent with the transfer of large amounts of energy through the atmosphere that gives rise to thermally-induced changes in the refractive index; application is then made to specific beamed propulsion scenarios. A brief portion of this report appeared as Appendix G of the 2012 Technical Memorandum. The second report, entitled "An Analytical Assessment of the Thermal Blooming Effects on the Propagation of Optical and Millimeter- Wave Focused Beam Waves For Power Beaming Applications" was written in October 2010 (not previously published), provides a more detailed treatment of the propagation problem and its effect on the overall characteristics of the beam such as its deflection as well as its radius. Comparisons are then made for power beaming using the disparate electromagnetic wavelengths of 1.06 microns and 2

  11. A fast chopper for medium energy beams

    NASA Astrophysics Data System (ADS)

    Madrak, R.; Wildman, D.

    2014-10-01

    The key elements have been constructed for a fast chopper system capable of removing single 2.5 MeV proton bunches spaced at 325 MHz. The average chopping rate is ~ 1 MHz. The components include a pulse delaying microstrip structure for deflecting the beam, high voltage (1.2 kV) fast (ns rise time) pulsers, and an associated wideband combiner. Various designs for the deflecting structures have been studied. Measurements of the microstrip structures' coverage factors and pulse shapes are presented.

  12. A fast chopper for medium energy beams

    SciTech Connect

    Madrak, R.; Wildman, D.

    2014-10-30

    The key elements have been constructed for a fast chopper system capable of removing single 2.5 MeV proton bunches spaced at 325 MHz. The average chopping rate is ~ 1 MHz. The components include a pulse delaying microstrip structure for deflecting the beam, high voltage (1.2 kV) fast (ns rise time) pulsers, and an associated wideband combiner. Various designs for the deflecting structures have been studied. Measurements of the microstrip structures' coverage factors and pulse shapes are presented.

  13. Polarimeters and Energy Spectrometers for the ILC Beam Delivery System

    SciTech Connect

    Boogert, S.; Hildreth, M.; Kafer, D.; List, J.; Monig, K.; Moffeit, K.C.; Moortgat-Pick, G.; Riemann, S.; Schreiber, H.J.; Schuler, P.; Torrence, E.; Woods, M.; /SLAC

    2009-02-24

    This article gives an overview of current plans and issues for polarimeters and energy spectrometers in the Beam Delivery System of the ILC. It is meant to serve as a useful reference for the Detector Letter of Intent documents currently being prepared. Concepts for high precision polarization and energy measurements exist. These concepts have resulted in detailed system layouts that are included in the RDR description for the Beam Delivery System. The RDR includes both upstream and downstream polarimeters and energy spectrometers for both beams. This provides needed complementarity and redundancy for achieving the precision required, with adequate control and demonstration of systematic errors. The BDS polarimeters and energy spectrometers need to be a joint effort of the ILC BDS team and the Detector collaborations, with collaboration members responsible for the performance and accuracy of the measurements. Details for this collaboration and assigning of responsibilities remain to be worked out. There is also a demonstrated need for Detector physicists to play an active role in the design and evaluation of accelerator components that impact beam polarization and beam energy capabilities, including the polarized source and spin rotator systems. A workshop was held in 2008 on ILC Polarization and Energy measurements, which resulted in a set of recommendations for the ILC design and operation. Additional input and action is needed on these from the Detector collaborations, the Research Director and the GDE. Work is continuing during the ILC engineering design phase to further optimize the polarimeter and energy spectrometer concepts and fully implement them in the ILC. This includes consideration for alternative methods, detailed design and cost estimates, and prototype and test beam activities.

  14. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    SciTech Connect

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-08-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  15. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    SciTech Connect

    Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2010-03-16

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  16. High energy electron beam joining of ceramic components

    SciTech Connect

    Turman, B.N.; Glass, S.J.; Halbleib, J.A.

    1997-07-01

    High strength, hermetic braze joints between ceramic components have been produced using high energy electron beams. With a penetration depth into a typical ceramic of {approximately}1 cm for a 10 MeV electron beam, this method provides the capability for rapid, transient brazing operations where temperature control of critical components is essential. The method deposits energy directly into a buried joint, allowing otherwise inaccessible interfaces to be brazed. Because of transient heating, higher thermal conductivity, lower heat capacity, and lower melting temperature of braze metals relative to the ceramic materials, a pulsed high power beam can melt a braze metal without producing excessive ceramic temperatures. We have demonstrated the feasibility of this process related to ceramic coupons as well as ceramic and glass tubes. The transient thermal response was predicted, using as input the energy absorption predicted from the coupled electron-photon transport analysis. The joining experiments were conducted with an RF Linac accelerator at 10-13 MV. The repetition rate of the pulsed beam was varied between 8 and 120 Hz, the average beam current was varied between 8 and 120 microamps, and the power was varied up to 1.5 kW. These beam parameters gave a beam power density between 0.2 to 2 kW/cm{sup 2}. The duration of the joining runs varied from 5 to 600 sec. Joining experiments have provided high strength between alumina - alumina and alumina - cermet joints in cylindrical geometry. These joints provided good hermetic seals. A series of tests was conducted to determine the minimum beam power and exposure time for producing, a hermetic seal.

  17. American Institute of Beamed Energy Propulsion: An Introduction

    NASA Astrophysics Data System (ADS)

    Pakhomov, Andrew V.

    2008-04-01

    To date ISBEP remains the main forum addressing the science and engineering of beamed energy propulsion. Hopefully, it will continue to serve BEP community in this capacity for years to come. The need for organization acting beyond ISBEP was discussed since the second symposium. This paper will address the following question: if our community is ready for having its own organization, a BEP institute, what new it should bring comparing to already existing conference. Such organization, an American Institute on Beamed Energy Propulsion (AIBEP) was recently established. The institute is designed as a nonprofit corporation serving the purpose "to promote the ideas, concepts and benefits of beamed-energy propulsion to research community, industry and society at large". The goals of the institute, expected outcomes and benefits of the organization and its membership will be discussed.

  18. Staging Laser Plasma Accelerators for Increased Beam Energy

    SciTech Connect

    Panasenko, D.; Shu, A. J.; Schroeder, C. B.; Gonsalves, A. J.; Nakamura, K.; Matlis, N. H.; Cormier-Michel, E.; Plateau, G.; Lin, C.; Toth, C.; Geddes, C. G. R.; Esarey, E.; Leemans, W. P.

    2009-01-22

    Staging laser plasma accelerators is an efficient way of mitigating laser pump depletion in laser driven accelerators and necessary for reaching high energies with compact laser systems. The concept of staging includes coupling of additional laser energy and transporting the electron beam from one accelerating module to another. Due to laser damage threshold constraints, in-coupling laser energy with conventional optics requires distances between the accelerating modules of the order of 10 m, resulting in decreased average accelerating gradient and complicated e-beam transport. In this paper we use basic scaling laws to show that the total length of future laser plasma accelerators will be determined by staging technology. We also propose using a liquid jet plasma mirror for in-coupling the laser beam and show that it has the potential to reduce distance between stages to the cm-scale.

  19. Surface modification using low energy ground state ion beams

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1990-01-01

    A method of effecting modifications at the surfaces of materials using low energy ion beams of known quantum state, purity, flux, and energy is presented. The ion beam is obtained by bombarding ion-generating molecules with electrons which are also at low energy. The electrons used to bombard the ion generating molecules are separated from the ions thus obtained and the ion beam is directed at the material surface to be modified. Depending on the type of ion generating molecules used, different ions can be obtained for different types of surface modifications such as oxidation and diamond film formation. One area of application is in the manufacture of semiconductor devices from semiconductor wafers.

  20. Advanced beamed-energy and field propulsion concepts

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.

    1983-01-01

    Specific phenomena which might lead to major advances in payload, range and terminal velocity of very advanced vehicle propulsion are studied. The effort focuses heavily on advanced propulsion spinoffs enabled by current government-funded investigations in directed-energy technology: i.e., laser, microwave, and relativistic charged particle beams. Futuristic (post-year 2000) beamed-energy propulsion concepts which indicate exceptional promise are identified and analytically investigated. The concepts must be sufficiently developed to permit technical understanding of the physical processes involved, assessment of the enabling technologies, and evaluation of their merits over conventional systems. Propulsion concepts that can be used for manned and/or unmanned missions for purposes of solar system exploration, planetary landing, suborbital flight, transport to orbit, and escape are presented. Speculations are made on the chronology of milestones in beamed-energy propulsion development, such as in systems applications of defense, satellite orbit-raising, global aerospace transportation, and manned interplanetary carriers.

  1. Beam Energy Measurement using the Hall C Beamline

    SciTech Connect

    Chen Yan; Roger Carlini; David Neuffer

    1993-05-01

    We propose to use the curved transport line into Hall C to measure the beam energy. With only dipoles powered, this transport arc has a dispersion of 12 cm/%. We propose to insert pairs of wire scanners at the entrance and exit of the arc to measure beam position and direction. These measurements, together with a calibrated dipole field, obtain an absolute beam energy measurement with {approx}10{sup -3} accuracy, according to error analyses. In operational mode, arc quads and sextupoles are powered to obtain a second order achromat with a dispersion of 2.1 cm/% at the arc center. A wire scanner at the arc center then obtains a relative energy measurement of {approx}10{sup -4} accuracy.

  2. Staging laser plasma accelerators for increased beam energy

    SciTech Connect

    Panasenko, Dmitriy; Shu, Anthony; Schroeder, Carl; Gonsalves, Anthony; Nakamura, Kei; Matlis, Nicholas; Cormier-Michel, Estelle; Plateau, Guillaume; Lin, Chen; Toth, Csaba; Geddes, Cameron; Esarey, Eric; Leemans, Wim

    2008-09-29

    Staging laser plasma accelerators is an efficient way of mitigating laser pump depletion in laser driven accelerators and necessary for reaching high energies with compact laser systems. The concept of staging includes coupling of additional laser energy and transporting the electron beam from one accelerating module to another. Due to laser damage threshold constraints, in-coupling laser energy with conventional optics requires distances between the accelerating modules of the order of 10m, resulting in decreased average accelerating gradient and complicated e-beam transport. In this paper we use basic scaling laws to show that the total length of future laser plasma accelerators will be determined by staging technology. We also propose using a liquid jet plasma mirror for in-coupling the laser beam and show that it has the potential to reduce distance between stages to the cm-scale.

  3. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    SciTech Connect

    Seletskiy, Sergei M.

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the ¯rst cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cool- ing. The Recycler Electron Cooler (REC) is the key component of the Teva- tron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV car- rying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 ¹rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible.

  4. High-energy accelerator for beams of heavy ions

    DOEpatents

    Martin, Ronald L.; Arnold, Richard C.

    1978-01-01

    An apparatus for accelerating heavy ions to high energies and directing the accelerated ions at a target comprises a source of singly ionized heavy ions of an element or compound of greater than 100 atomic mass units, means for accelerating the heavy ions, a storage ring for accumulating the accelerated heavy ions and switching means for switching the heavy ions from the storage ring to strike a target substantially simultaneously from a plurality of directions. In a particular embodiment the heavy ion that is accelerated is singly ionized hydrogen iodide. After acceleration, if the beam is of molecular ions, the ions are dissociated to leave an accelerated singly ionized atomic ion in a beam. Extraction of the beam may be accomplished by stripping all the electrons from the atomic ion to switch the beam from the storage ring by bending it in magnetic field of the storage ring.

  5. Ion beam extraction from electron cyclotron resonance ion sources and the subsequent low energy beam transport

    NASA Astrophysics Data System (ADS)

    Winklehner, Daniel

    Electron Cyclotron Resonance Ion Sources (ECRIS) are capable of delivering high currents of Highly Charged Ions (HCIs) to heavy ion accelerators (e.g.: to the future FRIB). The use of a sextupole magnet for confinement of the plasma inside the source imposes a unique triangular structure on the beam. This, together with the multitude of ion species that are extracted at the same time and the high axial magnetic field at the plasma aperture, resulting from additional confining solenoids, make the simulation and design of ECRIS extraction systems particularly challenging. The first objective of this thesis was to refine and test a semi-empirical simulation model of the formation and extraction of HCIs from ECR ion sources as well as their transport through the subsequent Low Energy Beam Transport (LEBT) system. To this end, a set of utility functions was written to simplify performing the simulations. In the LEBT system, another interesting, yet so far unanswered, question arises: The influence of space-charge effects on the beam and the level of space-charge compensation in the ECRIS beam line. This interesting topic quickly became the second main objective of the thesis. A Retarding Field Analyzer (RFA) was built and systematic measurements of the neutralization level in ECRIS LEBT systems were done for the first time as part of this thesis (this intensity and pressure regime was previously not well explored). The measured neutralization levels for typical ECRIS beams were found to be between 0% and 50% and agreed reasonably well with a simple formula developed by Gabovich et al. for highly neutralized proton and H- beams after it was re-derived and extended in this thesis for low neutralization and multiple species. Preliminary tests of the refined and integrated simulation model for the ECR ion sources VENUS and SuSI and their respective low energy beam transport systems include comparisons of measured beam currents, cross sections and emittances with the

  6. Range and Energy Straggling in Ion Beam Transport

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Tai, Hsiang

    2000-01-01

    A first-order approximation to the range and energy straggling of ion beams is given as a normal distribution for which the standard deviation is estimated from the fluctuations in energy loss events. The standard deviation is calculated by assuming scattering from free electrons with a long range cutoff parameter that depends on the mean excitation energy of the medium. The present formalism is derived by extrapolating Payne's formalism to low energy by systematic energy scaling and to greater depths of penetration by a second-order perturbation. Limited comparisons are made with experimental data.

  7. Energy Spread Reduction of Electron Beams Produced via Laser Wake

    SciTech Connect

    Pollock, Bradley Bolt

    2012-01-01

    Laser wakefield acceleration of electrons holds great promise for producing ultra-compact stages of GeV scale, high quality electron beams for applications such as x-ray free electron lasers and high energy colliders. Ultra-high intensity laser pulses can be self-guided by relativistic plasma waves over tens of vacuum diffraction lengths, to give >1 GeV energy in cm-scale low density plasma using ionization-induced injection to inject charge into the wake at low densities. This thesis describes a series of experiments which investigates the physics of LWFA in the self-guided blowout regime. Beginning with high density gas jet experiments the scaling of the LWFA-produced electron beam energy with plasma electron density is found to be in excellent agreement with both phenomenological theory and with 3-D PIC simulations. It is also determined that self-trapping of background electrons into the wake exhibits a threshold as a function of the electron density, and at the densities required to produce electron beams with energies exceeding 1 GeV a different mechanism is required to trap charge into low density wakes. By introducing small concentrations of high-Z gas to the nominal He background the ionization-induced injection mechanism is enabled. Electron trapping is observed at densities as low as 1.3 x 1018 cm-3 in a gas cell target, and 1.45 GeV electrons are demonstrated for the first time from LWFA. This is currently the highest electron energy ever produced from LWFA. The ionization-induced trapping mechanism is also shown to generate quasi-continuous electron beam energies, which is undesirable for accelerator applications. By limiting the region over which ionization-induced trapping occurs, the energy spread of the electron beams can be controlled. The development of a novel two-stage gas cell target provides the capability to tailor the gas composition in the longitudinal direction, and confine the trapping process to occur only in a

  8. Mechanical energy flow models of rods and beams

    NASA Technical Reports Server (NTRS)

    Wohlever, J. C.; Bernhard, R. J.

    1992-01-01

    It has been proposed that the flow of mechanical energy through a structural/acoustic system may be modeled in a manner similar to that of flow of thermal energy/in a heat conduction problem. If this hypothesis is true, it would result in relatively efficient numerical models of structure-borne energy in large built-up structures. Fewer parameters are required to approximate the energy solution than are required to model the characteristic wave behavior of structural vibration by using traditional displacement formulations. The energy flow hypothesis is tested in this investigation for both longitudinal vibration in rods and transverse flexural vibrations of beams. The rod is shown to behave approximately according to the thermal energy flow analogy. However, the beam solutions behave significantly differently than predicted by the thermal analogy unless locally-space-averaged energy and power are considered. Several techniques for coupling dissimilar rods and beams are also discussed. Illustrations of the solution accuracy of the methods are included.

  9. Solar Power Satellites: Creating the Market for Beamed Energy Propulsion

    NASA Astrophysics Data System (ADS)

    Coopersmith, Jonathan

    2010-05-01

    Beamed energy advocates must investigate the potential of major markets like space based solar satellites and space-based nuclear waste disposal. For BEP to succeed, its proponents must work with these possible users to generate interest and resources needed to develop BEP.

  10. MEIC Proton Beam Formation with a Low Energy Linac

    SciTech Connect

    Zhang, Yuhong

    2015-09-01

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

  11. Solar Power Satellites: Creating the Market for Beamed Energy Propulsion

    SciTech Connect

    Coopersmith, Jonathan

    2010-05-06

    Beamed energy advocates must investigate the potential of major markets like space based solar satellites and space-based nuclear waste disposal. For BEP to succeed, its proponents must work with these possible users to generate interest and resources needed to develop BEP.

  12. Large energy-spread beam diagnostics through quadrupole scans

    SciTech Connect

    Frederico, Joel; Adli, Erik; Hogan, Mark; Raubenheimer, Tor

    2012-12-21

    The Facility for Advanced Accelerator and Experimental Tests (FACET) is a new user facility at the SLAC National Accelerator Laboratory, servicing next-generation accelerator experiments. The 1.5% RMS energy spread of the FACET beam causes large chromatic aberrations in optics. These aberrations necessitate updated quadrupole scan fits to remain accurate.

  13. Energy spread of ion beams passing a gas stripper

    NASA Astrophysics Data System (ADS)

    Hartmann, B.; Kalbitzer, S.; Klatt, Ch.

    1997-05-01

    Since the energy spread of accelerated particle beams is not well known for tandem-type machines, we have measured current-energy distributions for a variety of ion beams delivered by our 3 MV tandem at varying stripper gas pressure. The energy widths of light ions produced from injected negatively charged atoms, such as H - and Fe -, are mainly due to the accelerating voltage ripple, whereas for heavier ions, such as C - and F -, energy straggling in the stripper gas dominates. In case of injected negatively charged molecules, such as NH 2- and CN -, Coulomb explosion in the gas stripper produces satellite peaks on both sides of the unshifted central line. These deviations from Gaussian line shape complicate precise lineshape analyses, as, for example, required in nuclear reaction Doppler spectrometry of vibrational states in target materials. The most relevant charge-exchange processes in the stripper gas will be discussed in some detail.

  14. Spiral design and beam dynamics for a variable energy cyclotron

    SciTech Connect

    Baltz, A.J.; Chasman, C.; Thorn, C.E.

    1981-01-01

    Beam-orbit studies were performed for the conversion of the SREL synchrocyclotron magnet for use as a room temperature, multiparticle, isochronous cyclotron. Based on model magnet measurements of field profiles for 8 to 23/sup 0/K gauss hill fields, a four sector spiral pole tip design has been realized which allows all isotope species of heavy ion beams to be accelerated to required final energies. The total spiral angle of 38/sup 0/ allows injection of the beams from the MP tandem into the cyclotron through a valley. The two valey RF system of 140 kV peak accelerates beams on harmonic numbers 2, 3, 4, 6 and 10 at 14 to 21 MHz. Computer calculations indicated acceptable ..nu../sub z/, ..nu../sub r/ and phase space beam characteristics and passing of resonances for typical beams considered: /sup 16/O at 8 and 150 MeV/amu, /sup 60/Ni at 100 MeV/amu and /sup 238/U at 2.5 and 16 MeV/amu. Single turn extraction is achieved with electrostatic deflection.

  15. Vibration piezoelectric energy harvester with multi-beam

    SciTech Connect

    Cui, Yan Zhang, Qunying Yao, Minglei; Dong, Weijie; Gao, Shiqiao

    2015-04-15

    This work presents a novel vibration piezoelectric energy harvester, which is a micro piezoelectric cantilever with multi-beam. The characteristics of the PZT (Pb(Zr{sub 0.53}Ti{sub 0.47})O{sub 3}) thin film were measured; XRD (X-ray diffraction) pattern and AFM (Atomic Force Microscope) image of the PZT thin film were measured, and show that the PZT (Pb(Zr{sub 0.53}Ti{sub 0.47})O{sub 3}) thin film is highly (110) crystal oriented; the leakage current is maintained in nA magnitude, the residual polarisation Pr is 37.037 μC/cm{sup 2}, the coercive field voltage Ec is 27.083 kV/cm, and the piezoelectric constant d{sub 33} is 28 pC/N. In order to test the dynamic performance of the energy harvester, a new measuring system was set up. The maximum output voltage of the single beam of the multi-beam can achieve 80.78 mV under an acceleration of 1 g at 260 Hz of frequency; the maximum output voltage of the single beam of the multi-beam is almost 20 mV at 1400 Hz frequency. .

  16. Phase Rotation of Muon Beams for Producing Intense Low-Energy Muon Beams

    SciTech Connect

    Neuffer, D.; Bao, Y.; Hansen, G.

    2016-01-01

    Low-energy muon beams are useful for rare decay searches, which provide access to new physics that cannot be addressed at high-energy colliders. However, muons are produced within a broad energy spread unmatched to the low-energy required. In this paper we outline a phase rotation method to significantly increase the intensity of low-energy muons. The muons are produced from a short pulsed proton driver, and develop a time-momentum correlation in a drift space following production. A series of rf cavities is used to bunch the muons and phase-energy rotate the bunches to a momentum of around 100 MeV/c. Then another group of rf cavities is used to decelerate the muon bunches to low-energy. This obtains ~0.1 muon per 8 GeV proton, which is significantly higher than currently planned Mu2e experiments, and would enable a next generation of rare decay searches, and other intense muon beam applications.

  17. In-situ determination of energy species yields of intense particle beams

    DOEpatents

    Kugel, Henry W.; Kaita, Robert

    1987-01-01

    An arrangement is provided for the in-situ determination of energy species yields of intense particle beams. The beam is directed onto a target surface of known composition, such that Rutherford backscattering of the beam occurs. The yield-energy characteristic response of the beam to backscattering from the target is analyzed using Rutherford backscattering techniques to determine the yields of energy species components of the beam.

  18. In-situ determination of energy species yields of intense particle beams

    DOEpatents

    Kugel, Henry W.; Kaita, Robert

    1987-03-03

    An arrangement is provided for the in-situ determination of energy species yields of intense particle beams. The beam is directed onto a target surface of known composition, such that Rutherford backscattering of the beam occurs. The yield-energy characteristic response of the beam to backscattering from the target is analyzed using Rutherford backscattering techniques to determine the yields of energy species components of the beam.

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

    SciTech Connect

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

    1995-05-05

    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. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

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

    SciTech Connect

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

    1995-12-31

    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.

  1. High energy transmission annular beam X-ray diffraction.

    PubMed

    Dicken, Anthony; Shevchuk, Alex; Rogers, Keith; Godber, Simon; Evans, Paul

    2015-03-01

    We demonstrate material phase retrieval by linearly translating extended polycrystalline samples along the symmetry axis of an annular beam of high-energy X-rays. A series of pseudo-monochromatic diffraction images are recorded from the dark region encompassed by the beam. We measure Bragg maxima from different annular gauge volumes in the form of bright spots in the X-ray diffraction intensity. We present the experiment data from three materials with different crystallographic structural properties i.e. near ideal, large grain size and preferred orientation. This technique shows great promise for analytical inspection tasks requiring highly penetrating radiation such as security screening, medicine and non-destructive testing.

  2. Energy harvesting under excitation of clamped-clamped beam

    NASA Astrophysics Data System (ADS)

    Batra, Ashok; Alomari, Almuatasim; Aggarwal, Mohan; Bandyopadhyay, Alak

    2016-04-01

    In this article, a piezoelectric energy harvesting has been developed experimentally and theoretically based on Euler- Bernoulli Theory. A PVDF piezoelectric thick film has attached along of clamped-clamped beam under sinusoidal base excitation of shaker. The results showed a good agreement between the experimental and simulation of suggested model. The voltage output frequency response function (FRF), current FRF, and output power has been studied under short and open circuit conditions at first vibration mode. The mode shape of the clamped-clamped beam for first three resonance frequency has been modeled and investigated using COMSOL Multiphysics and MATLAB.

  3. Determination of the beam quality index of high-energy photon beams under nonstandard reference conditions

    SciTech Connect

    Palmans, Hugo

    2012-09-15

    Purpose: At some modern radiotherapy machines it is not possible to achieve reference conditions for the measurement of beam quality indices used in dosimetry codes of practice, such as IAEA TRS-398 and AAPM TG-51. This work aims at providing self-consistent and simpler expressions and more accurate fits for a limited range of beams of interest than have been proposed previously for deriving these beam quality indices from measurements. Methods: The starting point is a formula proposed by Sauer [Med. Phys. 36, 4168-4172 (2009)] for deriving the beam quality index used in IAEA TRS-398, TPR{sub 20,10}, from a measurement of the tissue phantom ratio at depths of 20 cm and 10 cm in water for an s Multiplication-Sign s cm{sup 2} (equivalent) square field, TPR{sub 20,10}(s). First, a self-consistent version of this formula is established followed by a simpler version by making a linear approximation. A similar approach is proposed to derive the beam quality index used in AAPM TG-51, %dd(10){sub X}, from a measurement of PDD{sub 10}(s), the percentage depth dose at 10 cm for a square field with size s. All models were fitted to subsets of relevant data from BJR supplement 25. Results: The linear models for TPR{sub 20,10}(s) and exponential models for PDD{sub 10}(s) as a function of the (equivalent) square field size can reproduce the beam quality within 0.3% and beam quality correction factors within 0.05% for square field sizes ranging from 4 cm to 12 cm and nominal photon energies from 4 MV to 12 MV. For higher energy beams the errors are only slightly worse but for %dd(10){sub X}, an additional uncertainty component has to be considered for the electron contamination correction. Conclusions: The models proposed here can be used in practical recommendations for the dosimetry of small and nonstandard fields.

  4. Spacecraft Power Beaming Using High-Energy Lasers, Experimental Validation

    NASA Astrophysics Data System (ADS)

    Michael, Sherif

    2008-04-01

    The lifetime of many spacecrafts are often limited by degradation of their electrical power subsystem, e.g. radiation-damaged solar arrays or failed batteries. Being able to beam power from terrestrial sites using high energy lasers, could alleviate this limitation, extending the lifetime of billions of dollars of satellite assets, as well as providing additional energy for electric propulsion that can be used for stationkeeping and orbital changes. In addition, extensive research at the Naval Postgraduate School (NPS) has shown the potential for annealing damaged solar cells using lasers. This paper describes that research and a proposed experiment to demonstrate the relevant concepts of high energy laser power beaming to an NPS-built and operated satellite. Preliminary results of ground experiment of laser illuminations of some of the solar panels of one of the spacecrafts are also presented.

  5. Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

    SciTech Connect

    Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

    2004-11-10

    An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system.

  6. A high energy neutral beam system for reactors

    SciTech Connect

    Anderson, O.A.; Chan, C.F.; Cooper, W.S.; Leung, K.N.; Lietzke, A.F.; Kim, C.H.; Kunkel, W.B.; Kwan, J.W.; Purgalis, P.; Schlachter, A.S.

    1988-09-01

    High energy neutral beams provide a promising method of heating and driving current in steady-state tokamak fusion reactors. As an example, we have made a conceptual design of a neutral beam system for current drive on the International Thermonuclear Experimental Reactor (ITER). The system, based on electrostatic acceleration of D/sup /minus// ions, can deliver up to 100 MW of 1.6 MeV D/sup 0/ neutrals through three ports. Radiation protection is provided by locating sensitive beamline components 35 to 50 m from the reactor. In an application to a 3300 MW power reactor, a system delivering 120 MW of 2-2.4 MeV deuterium beams assisted by 21 MW of lower hybrid wave power drives 25 MA and provides an adequate plasma power gain (Q = 24) for a commercial fusion power plant. 8 refs., 1 fig., 2 tabs.

  7. Spheromak Energy Transport Studies via Neutral Beam Injection

    SciTech Connect

    McLean, H S; Hill, D N; Wood, R D; Jayakumar, J; Pearlstein, L D

    2008-02-11

    Results from the SSPX spheromak experiment provide strong motivation to add neutral beam injection (NBI) heating. Such auxiliary heating would significantly advance the capability to study the physics of energy transport and pressure limits for the spheromak. This LDRD project develops the physics basis for using NBI to heat spheromak plasmas in SSPX. The work encompasses three activities: (1) numerical simulation to make quantitative predictions of the effect of adding beams to SSPX, (2) using the SSPX spheromak and theory/modeling to develop potential target plasmas suitable for future application of neutral beam heating, and (3) developing diagnostics to provide the measurements needed for transport calculations. These activities are reported in several publications.

  8. Curing Composite Materials Using Lower-Energy Electron Beams

    NASA Technical Reports Server (NTRS)

    Byrne, Catherine A.; Bykanov, Alexander

    2004-01-01

    In an improved method of fabricating composite-material structures by laying up prepreg tapes (tapes of fiber reinforcement impregnated by uncured matrix materials) and then curing them, one cures the layups by use of beams of electrons having kinetic energies in the range of 200 to 300 keV. In contrast, in a prior method, one used electron beams characterized by kinetic energies up to 20 MeV. The improved method was first suggested by an Italian group in 1993, but had not been demonstrated until recently. With respect to both the prior method and the present improved method, the impetus for the use of electron- beam curing is a desire to avoid the high costs of autoclaves large enough to effect thermal curing of large composite-material structures. Unfortunately, in the prior method, the advantages of electron-beam curing are offset by the need for special walls and ceilings on curing chambers to shield personnel from x rays generated by impacts of energetic electrons. These shields must be thick [typically 2 to 3 ft (about 0.6 to 0.9 m) if made of concrete] and are therefore expensive. They also make it difficult to bring large structures into and out of the curing chambers. Currently, all major companies that fabricate composite-material spacecraft and aircraft structures form their layups by use of automated tape placement (ATP) machines. In the present improved method, an electron-beam gun is attached to an ATP head and used to irradiate the tape as it is pressed onto the workpiece. The electron kinetic energy between 200 and 300 keV is sufficient for penetration of the ply being laid plus one or two of the plies underneath it. Provided that the electron-beam gun is properly positioned, it is possible to administer the required electron dose and, at the same time, to protect personnel with less shielding than is needed in the prior method. Adequate shielding can be provided by concrete walls 6 ft (approximately equal to 1.8 m) high and 16 in. (approximately

  9. Dual energy scanning beam laminographic x-radiography

    DOEpatents

    Majewski, Stanislaw; Wojcik, Randolph F.

    1998-01-01

    A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible.

  10. Dual energy scanning beam laminographic x-radiography

    DOEpatents

    Majewski, S.; Wojcik, R.F.

    1998-04-21

    A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible. 6 figs.

  11. Exotic X-ray Sources from Intermediate Energy Electron Beams

    SciTech Connect

    Chouffani, K.; Wells, D.; Harmon, F.; Jones, J.L.; Lancaster, G.

    2003-08-26

    High intensity x-ray beams are used in a wide variety of applications in solid-state physics, medicine, biology and material sciences. Synchrotron radiation (SR) is currently the primary, high-quality x-ray source that satisfies both brilliance and tunability. The high cost, large size and low x-ray energies of SR facilities, however, are serious limitations. Alternatively, 'novel' x-ray sources are now possible due to new small linear accelerator (LINAC) technology, such as improved beam emittance, low background, sub-Picosecond beam pulses, high beam stability and higher repetition rate. These sources all stem from processes that produce Radiation from relativistic Electron beams in (crystalline) Periodic Structures (REPS), or the periodic 'structure' of laser light. REPS x-ray sources are serious candidates for bright, compact, portable, monochromatic, and tunable x-ray sources with varying degrees of polarization and coherence. Despite the discovery and early research into these sources over the past 25 years, these sources are still in their infancy. Experimental and theoretical research are still urgently needed to answer fundamental questions about the practical and ultimate limits of their brightness, mono-chromaticity etc. We present experimental results and theoretical comparisons for three exotic REPS sources. These are Laser-Compton Scattering (LCS), Channeling Radiation (CR) and Parametric X-Radiation (PXR)

  12. A method for calculating strain energy release rate based on beam theory

    NASA Technical Reports Server (NTRS)

    Sun, C. T.; Pandey, R. K.

    1993-01-01

    The Timoshenko beam theory was used to model cracked beams and to calculate the total strain energy release rate. The root rotation of the beam segments at the crack tip were estimated based on an approximate 2D elasticity solution. By including the strain energy released due to the root rotations of the beams during crack extension, the strain energy release rate obtained using beam theory agrees very well with the 2D finite element solution. Numerical examples were given for various beam geometries and loading conditions. Comparisons with existing beam models were also given.

  13. Improved method for calculating strain energy release rate based on beam theory

    NASA Technical Reports Server (NTRS)

    Sun, C. T.; Pandey, R. K.

    1994-01-01

    The Timoshenko beam theory was used to model cracked beams and to calculate the total strain-energy release rate. The root rotations of the beam segments at the crack tip were estimated based on an approximate two-dimensional elasticity solution. By including the strain energy released due to the root rotations of the beams during crack extension, the strain-energy release rate obtained using beam theory agrees very well with the two-dimensional finite element solution. Numerical examples were given for various beam geometries and loading conditions. Comparisons with existing beam models were also given.

  14. A scaled experiment to study energy dissipation process during longitudinal compression of charged particle beams

    NASA Astrophysics Data System (ADS)

    Sakai, Y.; Nakajima, M.; Hasegawa, J.; Kikuchi, T.; Horioka, K.

    2016-03-01

    Beam behavior during longitudinal bunch compression of charged particles was investigated using a compact simulator device based on electron beams. Beam current waveforms and bunch compression ratios were measured as a function of the initial beam current. We found that the current waveform became blunt and the compression ratio degraded at higher beam currents. These results indicate that space-charge fields dissipate the kinetic energy of beam particles.

  15. Si etching with reactive neutral beams of very low energy

    SciTech Connect

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Iwata, Naotaka; Hara, Tamio

    2014-12-14

    A Si etching process has been investigated with reactive neutral beams (NBs) extracted using a low acceleration voltage of less than 100 V from CF{sub 4} and Ar mixed plasmas. The etched Si profile shows that the etching process is predominantly anisotropic. The reactive NB has a constant Si etching rate in the acceleration voltage range from 20 V to 80 V. It is considered that low-energy NBs can trigger Si etching because F radicals adsorb onto the Si surface and weaken Si–Si bonds. The etching rate per unit beam flux is 33 times higher than that with Ar NB. These results show that the low-energy reactive NB is useful for damage-free high speed Si etching.

  16. Developments in low energy electron beam machinery and processes

    NASA Astrophysics Data System (ADS)

    Nablo, S. V.; Chrusciel, J.; Cleghorn, D. A.; Rangwalla, I.

    2003-08-01

    The engineering and development of a new generation of low energy, high power electron beam equipment is presented. Operating voltages range from 80 to 125 kV at widths to 1.65 m. At 110 kV these systems deliver 1000 Mrad m min -1 at 110 kV. Equipment operating power levels and their impact on reducing equipment size and cost are reviewed. The advantages of electron curing at these reduced operating voltages are described. The principles of the electron beam fluidized bed process for the treatment of powders and particulates in high-speed pneumatic transport are discussed. Typical system performances for polymer dissociation and crosslinking, or for agroproduct disinfestation and disinfection are presented. A process for the sterilization of polymer food containers employing the injection of low energy electrons through the open mouth has been developed. Some of its sterilization capabilities for bottles up to 2 l capacity are described.

  17. Options for integrated beam experiments for inertial fusion energy and high-energy density physics research

    NASA Astrophysics Data System (ADS)

    Leitner, M. A.; Celata, C. M.; Lee, E. P.; Logan, B. G.; Waldron, W. L.; Yu, S. S.; Barnard, J. J.

    2005-05-01

    The Heavy Ion Fusion Virtual National Laboratory (HIF-VNL), a collaboration among LBNL, LLNL, and PPPL, is presently focused on separate smaller-scale scientific experiments addressing key issues of future Inertial Fusion Energy (IFE) and High-Energy-Density-Physics (HEDP) drivers: the injection, transport, and focusing of intense heavy ion beams at currents from 25 to 600 mA. As a next major step in the HIF-VNL program, we aim for a fully integrated beam physics experiment, which allows integrated source-to-target physics research with a high-current heavy ion beam of IFE-relevant brightness with the goal of optimizing target focusing. This paper describes two rather different options for such an integrated experiment, the Integrated Beam Experiment (IBX) and the Neutralized Drift Compression Experiment (NDCX). Both proposals put emphasis on the unique capability for integrated injection, acceleration, compression, and focusing of a high-current, space-charge-dominated heavy ion beam.

  18. Beam energy dependence of azimuthal anisotropy at RHIC-PHENIX

    SciTech Connect

    Taranenko, A.

    2012-05-15

    Recent PHENIX measurements of the elliptic ({upsilon}{sub 2}) and hexadecapole ({upsilon}{sub 4}) Fourier flow coefficients for charged hadrons as a function of transverse momentum (p{sub T}), collision centrality and particle species are presented and compared with results from the PHOBOS and STAR Collaborations respectively. The status of extensions to future PHENIX measurements at lower beam energies is also discussed.

  19. Measurement of ultra-low ion energy of decelerated ion beam using a deflecting electric field

    NASA Astrophysics Data System (ADS)

    Thopan, P.; Suwannakachorn, D.; Tippawan, U.; Yu, L. D.

    2015-12-01

    In investigation on ultra-low-energy ion bombardment effect on DNA, an ion beam deceleration lens was developed for high-quality ultra-low-energy ion beam. Measurement of the ion energy after deceleration was necessary to confirm the ion beam really decelerated as theoretically predicted. In contrast to conventional methods, this work used a simple deflecting electrostatic field after the deceleration lens to bend the ion beam. The beam bending distance depended on the ion energy and was described and simulated. A system for the measurement of the ion beam energy was constructed. It consisted of a pair of parallel electrode plates to generate the deflecting electrical field, a copper rod measurement piece to detect ion beam current, a vernier caliper to mark the beam position, a stepping motor to translate the measurement rod, and a webcam-camera to read the beam bending distance. The entire system was installed after the ion-beam deceleration lens inside the large chamber of the bioengineering vertical ion beam line. Moving the measurement rod across the decelerated ion beam enabled to obtain beam profiles, from which the beam bending distance could be known and the ion beam energy could be calculated. The measurement results were in good agreement with theoretical and simulated results.

  20. Effective parameters in beam acoustic metamaterials based on energy band structures

    NASA Astrophysics Data System (ADS)

    Jing, Li; Wu, Jiu Hui; Guan, Dong; Hou, Mingming; Kuan, Lu; Shen, Li

    2016-07-01

    We present a method to calculate the effective material parameters of beam acoustic metamaterials. The effective material parameters of a periodic beam are calculated as an example. The dispersion relations and energy band structures of this beam are calculated. Subsequently, the effective material parameters of the beam are investigated by using the energy band structures. Then, the modal analysis and transmission properties of the beams with finite cells are simulated in order to confirm the correctness of effective approximation. The results show that the periodic beam can be equivalent to the homogeneous beam with dynamic effective material parameters in passband.

  1. Tumor Therapy with High-Energy Heavy-Ion Beams

    NASA Astrophysics Data System (ADS)

    Schardt, D.

    2001-09-01

    Heavy-ion beams offer favourable conditions for the treatment of deep-seated local tumors. The well defined range and the small lateral beam spread make it possible to deliver the dose with millimeter precision. In addition, heavy ions have an enhanced biological efficiency in the Bragg peak region which is caused by the dense ionization and the resulting reduced cellular repair rate. Furthermore, heavy ions offer the unique possibility of in-vivo range monitoring by applying Positron-Emission-Tomography (PET) techniques. Taking advantage of these clinically relevant properties, a therapy unit using 12C beams with energies of 80-430 MeV/u was constructed at GSI. The fully active beam delivery system includes a magnetic raster scan device providing a high degree of dose conformation to the target volume while healthy tissue and radiosensitive structures are spared to a maximum extent. In the framework of a clinical study 68 patients have been treated since December 1997 with promising results so far. Plans for a dedicated heavy-ion treatment center at the Radiological Clinic Heidelberg will be further pursued.

  2. Upgrade of beam energy measurement system at BEPC-II

    NASA Astrophysics Data System (ADS)

    Zhang, Jian-Yong; Cai, Xiao; Mo, Xiao-Hu; Guo, Di-Zhou; Wang, Jian-Li; Liu, Bai-Qi; Achasov, M. N.; Krasnov, A. A.; Muchnoi, N. Yu.; Pyata, E. E.; Mamoshkina, E. V.; Harris, F. A.

    2016-07-01

    The beam energy measurement system is of great importance for both BEPC-II accelerator and BES-III detector. The system is based on measuring the energies of Compton back-scattered photons. In order to meet the requirements of data taking and improve the measurement accuracy, the system has continued to be upgraded, which involves the updating of laser and optics subsystems, replacement of a view-port of the laser to the vacuum insertion subsystem, the use of an electric cooling system for a high purity germanium detector, and improvement of the data acquisition and processing subsystem. The upgrade system guarantees the smooth and efficient measurement of beam energy at BEPC-II and enables accurate offline energy values for further physics analysis at BES-III. Supported in part by National Natural Science Foundation of China (NSFC)(11375206, 10775142, 10825524, 11125525, 11235011), the Ministry of Science and Technology of China (2015CB856700, 2015CB856705), State key laboratory of particle and detection and electronics; and the CAS Center for Excellence in Particle Physics (CCEPP); the RFBR grant(14-02-00129-a), U.S. Department of Energy (DE-FG02-04ER41291, DE-FG02-05ER41374, DE-FG02-94ER40823, DESC0010118), U.S. National Science Foundation, part of this work related to the design of ZnSe viewports is supported by the Russian Science Foundation (14-50-00080)

  3. Study on astrophysical reactions using low-energy RI beams

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hidetoshi

    2009-10-01

    In recent years, low-energy RI beams can be produced in a good intensity and they have been used for studying many astrophysical reactions. One of the facilities producing low-energy RI beams is CRIB (CNS Radio-Isotope Beam separator) [1,2], an RI-beam separator of Center for Nuclear Study, University of Tokyo. Taking CRIB as an example, recent improvements on the RI-beam production and experimental results on astrophysical studies are presented. Several experimental approaches have been taken for the studies on astrophysical reactions.The feature of each method are discussed based on real measurements performed at CRIB. One is the direct method, applied for measurements of reactions such as (α,p) [3]. Another is the measurement of proton/alpha resonance scattering using the thick target method in inverse kinematics, by which we can obtain information on the resonances relevant in astrophysical reactions [4,5]. A recent fruitful result was from a measurement of proton resonance scattering using a ^7Be beam [5]. The energy level structure of ^8B, revealed by the experiment, is especially of interest as it is related with the ^7Be(p,γ) ^8B reaction, responsible for the production of ^8B neutrinos in the sun. We successfully determined parameters of resonances in ^8B below 6.7 MeV, which may affect the ^7Be(p,γ)^8B reaction rate at the solar temparature. Indirect methods, such as ANC and the Trojan Horse Method, were also used in some of the measurements.[4pt] [1] S. Kubono et al., Eur. Phys. J. A13 (2002) 217.[0pt] [2] Y. Yanagisawa et al., Nucl. Instrum. Meth. Phys. Res., Sect. A 539 (2005) 74.[0pt] [3] M. Notani et al., Nucl. Phys. A 764 (2004) 113c.[0pt] [4] T. Teranishi et al., Phys. Lett. B 650 (2007) 129.[0pt] [5] H. Yamaguchi et al., Phys. Lett. B 672 (2009) 230.

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

    NASA Astrophysics Data System (ADS)

    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.

  5. Equipment for Beam Current and Electron Energy Monitoring During Industry Irradiation.

    NASA Astrophysics Data System (ADS)

    Zavadtsev, A. A.

    1997-05-01

    The electron beam irradiation sterilization is placed first among all types of medical items sterilization. The quality of sterilization is determined by value of dose, which is in one's turn determined by beam current, electron energy and beam scanning system parameters. Therefore this parameters have to be controlled during the irradiation process. The equipment for beam current and electron energy monitoring allows to control beam current, electron energy spectrum and nominal deflection of electron beam when scanning during the irradiation process each scanning period or, for example, each tenth period by request.

  6. Beamed energy for space craft propulsion - Conceptual status and development potential

    NASA Technical Reports Server (NTRS)

    Sercel, Joel C.; Frisbee, Robert H.

    1987-01-01

    This paper outlines the results of a brief study that sought to identify and characterize beamed energy spacecraft propulsion concepts that may have positive impact on the economics of space industrialization. It is argued that the technology of beamed energy propulsion systems may significantly improve the prospects for near-term colonization of outer space. It is tentatively concluded that, for space industrialization purposes, the most attractive near-term beamed energy propulsion systems are based on microwave technology. This conclusion is reached based on consideration of the common features that exist between beamed microwave propulsion and the Solar Power Satellite (SPS) concept. Laser power beaming also continues to be an attractive option for spacecraft propulsion due to the reduced diffraction-induced beam spread afforded by laser radiation wavelengths. The conceptual status and development potential of a variety of beamed energy propulsion concepts are presented. Several alternative space transportation system concepts based on beamed energy propulsion are described.

  7. An Energy Saving System for a Beam Pumping Unit.

    PubMed

    Lv, Hongqiang; Liu, Jun; Han, Jiuqiang; Jiang, An

    2016-01-01

    Beam pumping units are widely used in the oil production industry, but the energy efficiency of this artificial lift machinery is generally low, especially for the low-production well and high-production well in the later stage. There are a number of ways for energy savings in pumping units, with the periodic adjustment of stroke speed and rectification of balance deviation being two important methods. In the paper, an energy saving system for a beam pumping unit (ESS-BPU) based on the Internet of Things (IoT) was proposed. A total of four types of sensors, including load sensor, angle sensor, voltage sensor, and current sensor, were used to detect the operating conditions of the pumping unit. Data from these sensors was fed into a controller installed in an oilfield to adjust the stroke speed automatically and estimate the degree of balance in real-time. Additionally, remote supervision could be fulfilled using a browser on a computer or smartphone. Furthermore, the data from a practical application was recorded and analyzed, and it can be seen that ESS-BPU is helpful in reducing energy loss caused by unnecessarily high stroke speed and a poor degree of balance. PMID:27187402

  8. An Energy Saving System for a Beam Pumping Unit

    PubMed Central

    Lv, Hongqiang; Liu, Jun; Han, Jiuqiang; Jiang, An

    2016-01-01

    Beam pumping units are widely used in the oil production industry, but the energy efficiency of this artificial lift machinery is generally low, especially for the low-production well and high-production well in the later stage. There are a number of ways for energy savings in pumping units, with the periodic adjustment of stroke speed and rectification of balance deviation being two important methods. In the paper, an energy saving system for a beam pumping unit (ESS-BPU) based on the Internet of Things (IoT) was proposed. A total of four types of sensors, including load sensor, angle sensor, voltage sensor, and current sensor, were used to detect the operating conditions of the pumping unit. Data from these sensors was fed into a controller installed in an oilfield to adjust the stroke speed automatically and estimate the degree of balance in real-time. Additionally, remote supervision could be fulfilled using a browser on a computer or smartphone. Furthermore, the data from a practical application was recorded and analyzed, and it can be seen that ESS-BPU is helpful in reducing energy loss caused by unnecessarily high stroke speed and a poor degree of balance. PMID:27187402

  9. An Energy Saving System for a Beam Pumping Unit.

    PubMed

    Lv, Hongqiang; Liu, Jun; Han, Jiuqiang; Jiang, An

    2016-05-13

    Beam pumping units are widely used in the oil production industry, but the energy efficiency of this artificial lift machinery is generally low, especially for the low-production well and high-production well in the later stage. There are a number of ways for energy savings in pumping units, with the periodic adjustment of stroke speed and rectification of balance deviation being two important methods. In the paper, an energy saving system for a beam pumping unit (ESS-BPU) based on the Internet of Things (IoT) was proposed. A total of four types of sensors, including load sensor, angle sensor, voltage sensor, and current sensor, were used to detect the operating conditions of the pumping unit. Data from these sensors was fed into a controller installed in an oilfield to adjust the stroke speed automatically and estimate the degree of balance in real-time. Additionally, remote supervision could be fulfilled using a browser on a computer or smartphone. Furthermore, the data from a practical application was recorded and analyzed, and it can be seen that ESS-BPU is helpful in reducing energy loss caused by unnecessarily high stroke speed and a poor degree of balance.

  10. Characteristics of low energy atom and molecule beams generated by the charge exchange reaction

    SciTech Connect

    Hara, Yasuhiro; Takashima, Seigo; Toyoda, Hirotaka; Sekine, Makoto; Hori, Masaru; Yamakawa, Koji; Den, Shoji

    2008-03-01

    A low energy NB source, which consisted of a surface wave plasma (SWP) source and two large diameter carbon electrodes, was developed for damageless etching of ultralarge-scale integrated devices. Ion beams were extracted from the SWP using two carbon electrodes, accelerated and injected to the process chamber, and then neutralized without energy loss by a charge exchange reaction. The energy distribution functions of an Ar ion beam and an Ar atom beam was observed using a quadrupole mass spectroscope equipped with an energy analyzer. The energy of the Ar ion beam and the Ar atom beam was controlled by the acceleration voltage. N{sub 2} ion and N ion beams were also extracted from a nitrogen plasma source. The intensity ratio of the N ion beam to the N{sub 2} ion beam was 5:9, indicating that N ions were efficiently generated in the nitrogen SWP. The N{sub 2} ion and N ion beams were changed to N{sub 2} molecule and N atom beams, respectively, through a charge exchange reaction without energy loss. The energy of these beams was controlled by the acceleration voltage and was in the region less of than 100 eV. When the acceleration voltage is higher than 40 V, not only the primary peaks due to the N{sub 2} ion beam or N ion beam were observed but also a low energy second peak was observed in the energy distribution. The energy of the low energy second peak was controlled by the acceleration voltage. It was concluded that the low energy second peak corresponds to the N{sub 2} molecule ion beam and the N ion beam, which is extracted from the second plasma generated in the space between the two carbon electrodes.

  11. Energy flow, energy density of Timoshenko beam and wave mode incoherence

    NASA Astrophysics Data System (ADS)

    Zhou, Jun; Rao, Zhushi; Ta, Na

    2015-10-01

    Time-averaged energy flow and energy density are of significance in vibration analysis. The wave decomposition method is more fruitful and global in physical sense than the state variables depicted point by point. By wave approach, the Timoshenko beam vibration field is decomposed into two distinct modes: travelling and evanescent waves. Consequently, the power and energy functions defined on these waves' amplitude and phase need to be established. However, such formulas on Timoshenko beam are hardly found in literatures. Furthermore, the incoherence between these two modes is of theoretical and practical significance. This characteristic guarantees that the resultant power or energy of a superposed wave field is equal to the sum of the power or energy that each wave mode would generate individually. Unlike Euler-Bernoulli beam, such incoherence in the Timoshenko beam case has not been theoretically proved so far. Initially, the power and energy formulas based on wave approach and the corresponding incoherence proof are achieved by present work, both in theoretical and numerical ways. Fortunately, the theoretical and numerical results show that the travelling and evanescent wave modes are incoherent with each other both on power and energy functions. Notably, the energy function is unconventional and self-defined in order to obtain the incoherence. Some remarkable power transmission characteristics of the evanescent wave are also illustrated meanwhile.

  12. Strain energy release rate distributions for double cantilever beam specimens

    NASA Technical Reports Server (NTRS)

    Crews, J. H., Jr.; Shivakumar, K. N.; Raju, I. S.

    1991-01-01

    A 24-ply composite double cantilever-beam specimen under mode I (opening) loading has been analyzed by a 3D FEM code that calculated along a straight delamination starter for several different specimen materials. An isotropic specimen was found to have a strain-energy release rate distribution which varied along its delamination front due to the boundary-layer effect and another effect associated with the anticlastic curvature of the bent specimen arms. A 0-deg graphite-reinforced epoxy specimen had a nearly-uniform strain-energy release rate distribution which dropped only near the edge, due to the boundary-layer effect, and a +/- 45-deg graphite/epoxy specimen exhibited a pronounced strain-energy release rate variation across the specimen width.

  13. Energy dependence of island nucleation density during ion beam deposition

    NASA Astrophysics Data System (ADS)

    Pomeroy, Joshua M.; Brock, Joel D.

    2002-03-01

    Thin copper films were grown on single crystal copper substrates using highly collimated copper ion beams with precisely controlled incidence energies. The energetic collisions between the copper ions and the surface can form adatom-vacancy pairs or sputter eject atoms into the vaccuum. Island nucleation densities are affected by these atomistic mechanisms, which increase surface adatom densities and surface defect densities. This paper reports STM measurements of the island nucleation density for films grown both thermally and at energies between 10-150 eV. The measured island nucleation density systematically deviates with increasing energy from the density predicted by mean field nucleation theory (J.A. Venables, et.al., Rep. Prog. Phys. 47 (1984) p. 399-459). This deviation can be understood using a phenomenological extension of mean field nucleation theory that includes the effects of adatom-vacancy pair production and sputter ejection on the effective flux.

  14. Stable topological insulators achieved using high energy electron beams

    PubMed Central

    Zhao, Lukas; Konczykowski, Marcin; Deng, Haiming; Korzhovska, Inna; Begliarbekov, Milan; Chen, Zhiyi; Papalazarou, Evangelos; Marsi, Marino; Perfetti, Luca; Hruban, Andrzej; Wołoś, Agnieszka; Krusin-Elbaum, Lia

    2016-01-01

    Topological insulators are potentially transformative quantum solids with metallic surface states which have Dirac band structure and are immune to disorder. Ubiquitous charged bulk defects, however, pull the Fermi energy into the bulk bands, denying access to surface charge transport. Here we demonstrate that irradiation with swift (∼2.5 MeV energy) electron beams allows to compensate these defects, bring the Fermi level back into the bulk gap and reach the charge neutrality point (CNP). Controlling the beam fluence, we tune bulk conductivity from p- (hole-like) to n-type (electron-like), crossing the Dirac point and back, while preserving the Dirac energy dispersion. The CNP conductance has a two-dimensional character on the order of ten conductance quanta and reveals, both in Bi2Te3 and Bi2Se3, the presence of only two quantum channels corresponding to two topological surfaces. The intrinsic quantum transport of the topological states is accessible disregarding the bulk size. PMID:26961901

  15. Measuring pion beta decay with high-energy pion beams

    SciTech Connect

    McFarlane, W.K. |; Hoffman, C.M.

    1993-02-01

    Improved measurements of the pion beta decay rate are possible with an intense high-energy pion beam. The rate for the decay {pi}{sup +} {yields} {pi}{sup 0}e{sup +}v{epsilon} is predicted by the Standard Model (SM) to be R({pi}{sup +} {yields} {pi}{sup 0}e{sup +}v{epsilon}) = 0.3999{plus_minus}0.0005 s{sup {minus}1}. The best experimental number, obtained using in-flight decays, is R({pi}{sup +} {yields} {pi}{sup 0}e{sup +}v{epsilon}) = 0.394 {plus_minus} 0.015 s{sup {minus}1}. A precise measurement would test the SM by testing the unitarity of the Cabibbo-Kobayashi-Maskawa matrix for which one analysis of the nuclear beta decay data has shown a 0.4% discrepancy. Several nuclear correction factors, needed for nuclear decay, are not present for pion beta decay, so that an experiment at the 0.2% level would be a significant one. Detailed study of possible designs will be needed, as well as extensive testing of components. The reduction of systematic errors to the 0.1% level can only be done over a period of years with a highly stable apparatus and beam. At a minimum, three years of occupancy of a beam line, with 800 hours per year, would be required.

  16. Measuring pion beta decay with high-energy pion beams

    SciTech Connect

    McFarlane, W.K. Temple Univ., Philadelphia, PA ); Hoffman, C.M. )

    1993-01-01

    Improved measurements of the pion beta decay rate are possible with an intense high-energy pion beam. The rate for the decay [pi][sup +] [yields] [pi][sup 0]e[sup +]v[epsilon] is predicted by the Standard Model (SM) to be R([pi][sup +] [yields] [pi][sup 0]e[sup +]v[epsilon]) = 0.3999[plus minus]0.0005 s[sup [minus]1]. The best experimental number, obtained using in-flight decays, is R([pi][sup +] [yields] [pi][sup 0]e[sup +]v[epsilon]) = 0.394 [plus minus] 0.015 s[sup [minus]1]. A precise measurement would test the SM by testing the unitarity of the Cabibbo-Kobayashi-Maskawa matrix for which one analysis of the nuclear beta decay data has shown a 0.4% discrepancy. Several nuclear correction factors, needed for nuclear decay, are not present for pion beta decay, so that an experiment at the 0.2% level would be a significant one. Detailed study of possible designs will be needed, as well as extensive testing of components. The reduction of systematic errors to the 0.1% level can only be done over a period of years with a highly stable apparatus and beam. At a minimum, three years of occupancy of a beam line, with 800 hours per year, would be required.

  17. Characterization of intense ion beam energy density and beam induced pressure on the target with acoustic diagnostics

    SciTech Connect

    Pushkarev, A. I.; Isakova, Yu. I.; Khailov, I. P.; Yu, Xiao

    2013-08-15

    We have developed the acoustic diagnostics based on a piezoelectric transducer for characterization of high-intensity pulsed ion beams. The diagnostics was tested using the TEMP-4M accelerator (150 ns, 250–300 kV). The beam is composed of C{sup +} ions (85%) and protons, the beam energy density is 0.5–5 J/cm{sup 2} (depending on diode geometry). A calibration dependence of the signal from a piezoelectric transducer on the ion beam energy density is obtained using thermal imaging diagnostics. It is shown that the acoustic diagnostics allows for measurement of the beam energy density in the range of 0.1–2 J/cm{sup 2}. The dependence of the beam generated pressure on the input energy density is also determined and compared with the data from literature. The developed acoustic diagnostics do not require sophisticated equipment and can be used for operational control of pulsed ion beam parameters with a repetition rate of 10{sup 3} pulses/s.

  18. Characterization of intense ion beam energy density and beam induced pressure on the target with acoustic diagnostics.

    PubMed

    Pushkarev, A I; Isakova, Yu I; Yu, Xiao; Khailov, I P

    2013-08-01

    We have developed the acoustic diagnostics based on a piezoelectric transducer for characterization of high-intensity pulsed ion beams. The diagnostics was tested using the TEMP-4M accelerator (150 ns, 250-300 kV). The beam is composed of C(+) ions (85%) and protons, the beam energy density is 0.5-5 J∕cm(2) (depending on diode geometry). A calibration dependence of the signal from a piezoelectric transducer on the ion beam energy density is obtained using thermal imaging diagnostics. It is shown that the acoustic diagnostics allows for measurement of the beam energy density in the range of 0.1-2 J∕cm(2). The dependence of the beam generated pressure on the input energy density is also determined and compared with the data from literature. The developed acoustic diagnostics do not require sophisticated equipment and can be used for operational control of pulsed ion beam parameters with a repetition rate of 10(3) pulses∕s.

  19. Conserved vector current test using low energy beta beams

    SciTech Connect

    Balantekin, A.B.; Jesus, J.H. de; Lazauskas, R.; Volpe, C.

    2006-04-01

    We discuss the possibility of testing the weak currents and, in particular, the weak magnetism term through the measurement of the {nu}{sub e}+p{yields}e{sup +}+n reaction at a low energy beta-beam facility. We analyze the sensitivity using both the total number of events and the angular distribution of the positrons emitted in a water Cerenkov detector. We show that the weak magnetism form factor might be determined with better than several percent accuracy using the angular distribution. This offers a new way of testing the conserved vector current hypothesis.

  20. Replacement of chemical rocket launchers by beamed energy propulsion.

    PubMed

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%. PMID:25402933

  1. Beamed Energy Propulsion by Means of Target Ablation

    NASA Astrophysics Data System (ADS)

    Rosenberg, Benjamin A.

    2004-03-01

    This paper describes hundreds of pendulum tests examining the beamed energy conversion efficiency of different metal targets coated with multiple liquid enhancers. Preliminary testing used a local laser with photographic paper targets, with no liquid, water, canola oil, or methanol additives. Laboratory experimentation was completed at Wright-Patterson AFB using a high-powered laser, and ballistic pendulums of aluminum, titanium, or copper. Dry targets, and those coated with water, methanol and oil were repeatedly tested in laboratory conditions. Results were recorded on several high-speed digital video cameras, and the conversion efficiency was calculated. Paper airplanes successfully launched using BEP were likewise recorded.

  2. Replacement of chemical rocket launchers by beamed energy propulsion.

    PubMed

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%.

  3. Beamed Energy Propulsion by Means of Target Ablation

    SciTech Connect

    Rosenberg, Benjamin A.

    2004-03-30

    This paper describes hundreds of pendulum tests examining the beamed energy conversion efficiency of different metal targets coated with multiple liquid enhancers. Preliminary testing used a local laser with photographic paper targets, with no liquid, water, canola oil, or methanol additives. Laboratory experimentation was completed at Wright-Patterson AFB using a high-powered laser, and ballistic pendulums of aluminum, titanium, or copper. Dry targets, and those coated with water, methanol and oil were repeatedly tested in laboratory conditions. Results were recorded on several high-speed digital video cameras, and the conversion efficiency was calculated. Paper airplanes successfully launched using BEP were likewise recorded.

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

    SciTech Connect

    Wang, Guimei

    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

  5. Emittance and Energy Measurements of Low-Energy Electron Beam Using Optical Transition Radiation Techniques

    NASA Astrophysics Data System (ADS)

    Sakamoto, Fumito; Iijima, Hokuto; Dobashi, Katsuhiro; Imai, Takayuki; Ueda, Toru; Watanabe, Takahiro; Uesaka, Mitsuru

    2005-03-01

    Emittance and energy of an electron beam in the range of 8 to 22 MeV were measured via optical transition radiation (OTR) techniques. The beam divergence effect on observations of the far-field OTR image at low energies was studied by means of numerical analysis. The numerical analysis indicates that if the beam divergence is under 1.5 mrad, a simultaneous single-shot measurement of emittance and energy is possible. The results of the single-shot experiment agree with independent measurements conducted using the quadrupole scan method and an electron spectrometer. The experiments were performed with an S-band linac at the Nuclear Engineering Research Laboratory, The University of Tokyo (UTNL).

  6. Feasibility of a 90° electric sector energy analyzer for low energy ion beam characterization

    SciTech Connect

    Mahinay, C. L. S. Ramos, H. J.; Wada, M.

    2015-02-15

    A simple formula to calculate refocusing by locating the output slit at a specific distance away from the exit of 90° ion deflecting electric sector is given. Numerical analysis is also performed to calculate the ion beam trajectories for different values of the initial angular deviation of the beam. To validate the theory, a compact (90 mm × 5.5 mm × 32 mm) 90° sector ESA is fabricated which can fit through the inner diameter of a conflat 70 vacuum flange. Experimental results show that the dependence of resolution upon the distance between the sector exit and the Faraday cup agrees with the theory. The fabricated 90° sector electrostatic energy analyzer was then used to measure the space resolved ion energy distribution functions of an ion beam with the energy as low as 600 eV.

  7. Investigation of beam non-uniformity after cross-beam energy transfer in a gas filled hohlraum

    NASA Astrophysics Data System (ADS)

    Schneider, M. B.; Hinkel, D. E.; Rosen, M. D.; Callahan, D. A.; Michel, P. A.; Moore, A. S.; Moody, J. D.

    2015-11-01

    Control of hotspot symmetry in an ignition capsule imploded by the x-ray drive in a high gas-filled cylindrical hohlraum at the NIF currently requires cross-beam energy transfer (CBET) from the outer beams to the inner beams. CBET occurs in the central region of the laser entrance hole (LEH) where the laser beams overlap. Linear gain models applied to individual rays indicate that CBET is not uniform across the beam profile, producing a non-uniform spatial distribution on the beams that varies in time. This changing spatial distribution could introduce asymmetries in the x-ray drive applied to the ignition capsule and should be quantified. We are investigating the effects of CBET using the Quartraum experimental platform. This platform uses an LEH-only target designed to isolate the effect of CBET on the spatial-intensity distribution of the inner beams by minimizing the effect of absorption and backscatter. A time resolved image of two inner beams is captured on a high Z witness plate. Experimental results showing how the beam's x-ray foot print on the witness plate changes as a function of Δλ will be shown and compared to models.

  8. Generalized energy-aperture product limit for multi-beam and spotlight SARs

    SciTech Connect

    Karr, T.J.

    1995-12-21

    The SAR energy-aperture product limit is extended to multi-beam SARS, Spotlight and moving spotlight SARS. This fundamental limit bounds the tradeoff between energy and antenna size. The kinematic relations between design variables such as platform speed, pulse repetition frequency, beam width and area rate are analyzed in a unified framework applicable to a wide variety of SARs including strip maps, spotlights, vermer arrays and multi-beam SARS, both scanning and swept-beam. Then the energy-aperture product limit is derived from the signal-to noise requirement and the kinematic constraints. The derivation clarifies impact of multiple beams and spotlighting on SAR performance.

  9. Online beam energy measurement of Beijing electron positron collider II linear accelerator.

    PubMed

    Wang, S; Iqbal, M; Liu, R; Chi, Y

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

  10. Online beam energy measurement of Beijing electron positron collider II linear accelerator

    NASA Astrophysics Data System (ADS)

    Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

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

    NASA Astrophysics Data System (ADS)

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

    2016-11-01

    A first prototype of transport beam-line for laser-driven ion beams to be used for the handling of particles accelerated by high-power laser interacting with solid targets has been realized at INFN. The goal is the production of a controlled and stable beam in terms of energy and angular spread. The beam-line consists of two elements: an Energy Selection System (ESS), already realized and characterized with both conventional and laser-accelerated beams, and a Permanent Magnet Quadrupole system (PMQ) designed, in collaboration with SIGMAPHI (Fr), to improve the ESS performances. In this work a description of the ESS system and some results of its characterization with conventional beams are reported, in order to provide a complete explanation of the acceptance calculation. Then, the matching with the PMQ system is presented and, finally, the results of preliminary simulations with a realistic laser-driven energy spectrum are discussed demonstrating the possibility to provide a good quality beam downstream the systems.

  12. Electromechanical decoupled model for cantilever-beam piezoelectric energy harvesters

    NASA Astrophysics Data System (ADS)

    Tan, T.; Yan, Z.; Hajj, M.

    2016-09-01

    Analysis of cantilever-based piezoelectric energy harvesting systems is usually performed using coupled equations that represent the mechanical displacement and the voltage output. These equations are then solved simultaneously. In contrast to this representation, we use analytical solutions of the governing equation to derive an algebraic equation of the power as a function of the beam displacement, electromechanical coefficients, and the load resistance. Such an equation can be more useful in the design of such harvesters. Particularly, the mechanical displacement is computed from a mechanical governing equation with modified natural frequency and damping ratio that account for the electromechanical coupling. The voltage and the harvested power are then obtained by relating them directly to the mechanical displacement. We validate the proposed analysis by comparing its solution including the tip displacement and harvested power with those of numerical simulations of the governing equations. To demonstrate the generality of the proposed approach, we consider the cases of base excitation, galloping, and autoparametric vibration. The model proposed in this study simplifies the electromechanical coupling problem for practical applications of cantilever-beam piezoelectric energy harvesting systems.

  13. Use of off-axis injection as an alternative to geometrically merging beams in an energy-recovering linac

    DOEpatents

    Douglas, David R.

    2012-01-10

    A method of using off-axis particle beam injection in energy-recovering linear accelerators that increases operational efficiency while eliminating the need to merge the high energy re-circulating beam with an injected low energy beam. In this arrangement, the high energy re-circulating beam and the low energy beam are manipulated such that they are within a predetermined distance from one another and then the two immerged beams are injected into the linac and propagated through the system. The configuration permits injection without geometric beam merging as well as decelerated beam extraction without the use of typical beamline elements.

  14. Low energy ion beam induced changes in ETFE polymer

    NASA Astrophysics Data System (ADS)

    Parada, M. A.; Delalez, N.; de Almeida, A.; Muntele, C.; Muntele, I.; Ila, D.

    2006-01-01

    Low energy ion beam bombardment of ethylenetetrafluoroethylene (ETFE) modifies the physical and chemical properties of the polymer surface in ways that enhance or compromise applications in the technological and medical physics fields. When a material is exposed to ionizing radiation, its changes depends on the type, energy and intensity of the applied radiation. In order to determine the nature of the induced radiation changes, ETFE films were bombarded with fluences from 1012 up to 1015 ions/cm2 of keV N and protons. The emission of gaseous species during the bombardments was monitored with a residual gas analyser (RGA). The bombarded films were analysed with optical absorption photospectrometry (OAP), Fourier transform infrared (FTIR) and micro-Raman spectrometries that determine the chemical nature of the structural changes caused by ions bombardment.

  15. Future Physics Opportunities in Beam Energy Scan at RHIC

    NASA Astrophysics Data System (ADS)

    Xu, Nu

    2015-10-01

    In the first phase of the beam energy scan program (BES-I) at RHIC, we have collected data from Au +Au collisions at the center of mass energy range from 7.7 GeV to 39 GeV, corresponding to the baryonic chemical potential of 420 MeV to 120 MeV, respectively. We have observed the disappearance of the suppression of leading hadrons at large pT, break down of the quark scaling in the identified particle elliptic flow, the net-proton directed flow slope dv1/dy shows a minimum with negative sign, and a non-monotonical behavior of the net-proton correlation function (the fourth order) at the energy less than 20 GeV. All of these observations indicate that the property of the medium at high baryon density is dramatically different from that created at the RHIC top energy where the baryon density is small and partonic interactions are dominant. In this talk I will first review what we have learned in RHIC BES-I. Then I will discuss the opportunities in the future bean energy scan program in order to address key questions regarding the QCD phase structure including the illusive critical point. I will stress that adequate detector upgrades, focused at the large baryon density region, are essential for the physics program.

  16. Modulator considerations for beam chopping in the low energy beam transport at the SSC Laboratory

    SciTech Connect

    Anderson, D.; Pappas, G.

    1991-06-01

    Beam chopping in the low energy transport line at the Superconducting Super Collider Laboratory is accomplished using an electrostatic deflection system. LINAC requirements dictate the design of two modulators operating at 10 Hz with rise and fall times (as measured from approximately 10--99%) of {approximately}100 ns. Design of the first pulser, normally at 10 kV and pulsed to ground potential, utilizes a transformer-coupled diode-clamped solid state circuit to achieve the 2--35 {mu}s pulse width range required. The second pulser, which pulses from ground to approximately 7 kV, relies on a series vacuum tube circuit. The current designs, as well as recent test results and other circuit topologies considered, will be presented. 6 refs.

  17. Beam Fields and Energy Dissipation Inside the the BE Beam Pipe of the Super-B Detector

    SciTech Connect

    Novokhatski, Alexander; Sullivan, Michael; /SLAC

    2010-09-10

    We study the bunch field diffusion and energy dissipation in the beam pipe of the Super-B detector, which consists of two coaxial Be thin pipes (half a millimeter). Cooling water will run between these two pipes. Gold and nickel will be sputtered (several microns) onto the beryllium pipe at different sides. The Maxwell equations for the beam fields in these thin layers are solved numerically for the case of infinite pipes. We also calculate the amplitude of the electromagnetic fields outside the beam pipe, which may be noticeable as the beam current can reach 4 A in each beam. Results of simulations are used for the design of this central part of the Super-B detector.

  18. Future of the Beam Energy Scan program at RHIC

    SciTech Connect

    Odyniec, Grazyna; Bravina, L.; Foka, Y.; Kabana, S.

    2015-05-29

    The first exploratory phase of a very successful Beam Energy Scan Program at RHIC was completed in 2014 with Au+Au collisions at energies ranging from 7 to 39 GeV. Data sets taken earlier extended the upper limit of energy range to the √sNN of 200 GeV. This provided an initial look into the uncharted territory of the QCD phase diagram, which is considered to be the single most important graph of our field. The main results from BES phase I, although effected by large statistical errors (steeply increasing with decreasing energy), suggest that the highest potential for discovery of the QCD Critical Point lies bellow √sNN 20 GeV. Here, we discuss the plans and the preparation for phase II of the BES program, with an order of magnitude larger statistics, which is planned for 2018-2019. The BES II will focus on Au+Au collisions at √sNN from 20 to 7 GeV in collider mode, and from √sNN 7 to 3.5 GeV in the fixed target mode, which will be run concurrently with the collider mode operation.

  19. Future of the Beam Energy Scan program at RHIC

    DOE PAGESBeta

    Odyniec, Grazyna; Bravina, L.; Foka, Y.; Kabana, S.

    2015-05-29

    The first exploratory phase of a very successful Beam Energy Scan Program at RHIC was completed in 2014 with Au+Au collisions at energies ranging from 7 to 39 GeV. Data sets taken earlier extended the upper limit of energy range to the √sNN of 200 GeV. This provided an initial look into the uncharted territory of the QCD phase diagram, which is considered to be the single most important graph of our field. The main results from BES phase I, although effected by large statistical errors (steeply increasing with decreasing energy), suggest that the highest potential for discovery of themore » QCD Critical Point lies bellow √sNN 20 GeV. Here, we discuss the plans and the preparation for phase II of the BES program, with an order of magnitude larger statistics, which is planned for 2018-2019. The BES II will focus on Au+Au collisions at √sNN from 20 to 7 GeV in collider mode, and from √sNN 7 to 3.5 GeV in the fixed target mode, which will be run concurrently with the collider mode operation.« less

  20. Inverse planning of energy-modulated electron beams in radiotherapy

    SciTech Connect

    Gentry, John R. . E-mail: gentryj@gmh.org; Steeves, Richard; Paliwal, Bhudatt A.

    2006-01-01

    The use of megavoltage electron beams often poses a clinical challenge in that the planning target volume (PTV) is anterior to other radiosensitive structures and has variable depth. To ensure that skin as well as the deepest extent of the PTV receives the prescribed dose entails prescribing to a point beyond the depth of peak dose for a single electron energy. This causes dose inhomogeneities and heightened potential for tissue fibrosis, scarring, and possible soft tissue necrosis. Use of bolus on the skin improves the entrant dose at the cost of decreasing the therapeutic depth that can be treated. Selection of a higher energy to improve dose homogeneity results in increased dose to structures beyond the PTV, as well as enlargement of the volume receiving heightened dose. Measured electron data from a linear accelerator was used as input to create an inverse planning tool employing energy and intensity modulation using bolus (e-IMRT{sup TM}). Using tools readily available in a radiotherapy department, the applications of energy and intensity modulation on the central axis makes it possible to remove hot spots of 115% or more over the depths clinically encountered. The e-IMRT{sup TM} algorithm enables the development of patient-specific dose distributions with user-defined positions of peak dose, range, and reduced dose to points beyond the prescription point.

  1. Experimental study of magnetically confined hollow electron beams in the Tevatron as collimators for intense high-energy hadron beams

    SciTech Connect

    Stancari, G.; Annala, G.; Shiltsev, V.; Still, D.; Valishev, A.; Vorobiev, L.; /Fermilab

    2011-03-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable losses. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and tested at Fermilab for this purpose. It was installed in one of the Tevatron electron lenses in the summer of 2010. We present the results of the first experimental tests of the hollow-beam collimation concept on 980-GeV antiproton bunches in the Tevatron.

  2. Scheme for Low Energy Beam Transport with a Non-Neutralized Section

    SciTech Connect

    Shemyakin, A.; Prost, L.

    2015-04-23

    A typical Low Energy Beam Transport (LEBT) design relies on dynamics with nearly complete beam space charge neutralization over the entire length of the LEBT. This paper argues that, for a beam with modest perveance and uniform current density distribution when generated at the source, a downstream portion of the LEBT can be un-neutralized without significant emittance growth.

  3. High resolution at low beam energy in the SEM: resolution measurement of a monochromated SEM.

    PubMed

    Michael, Joseph R

    2011-01-01

    The resolution of secondary electron low beam energy imaging of a scanning electron microscope equipped with a monochromator is quantitatively measured using the contrast transfer function (CTF) method. High-resolution images, with sub-nm resolutions, were produced using low beam energies. The use of a monochromator is shown to quantitatively improve the resolution of the SEM at low beam energies by limiting the chromatic aberration contribution to the electron probe size as demonstrated with calculations and images of suitable samples. Secondary electron image resolution at low beam energies is ultimately limited by noise in the images as shown by the CTFs.

  4. Beam chopper For the Low-Energy Undulator Test Line (LEUTL) in the APS

    SciTech Connect

    Kang, Y.; Wang, J.; Milton, S.; Teng, L.

    1997-08-01

    The low-energy undulator test line (LEUTL) is being built and will be tested with a short beam pulse from an rf gun in the Advanced Photon Source (APS) at the Argonne National Laboratory. In the LEUTL a beam chopper is used after the rf gun to deflect the unwanted beam to a beam dump. The beam chopper consists of a permanent magnet and an electric deflector that can compensate for the magnetic deflection. A 30-kV pulsed power supply is used for the electric deflector. The chopper subsystem was assembled and tested for beamline installation. The electrical and beam properties of the chopper assembly are presented.

  5. Investigations of proton beam energy of the MC-50 cyclotron at KIRAMS

    NASA Astrophysics Data System (ADS)

    Khandaker, Mayeen Uddin; Kim, Guinyun; Kim, Kwangsoo; Bin Abu Kassim, Hasan; Nikouravan, Bijan

    2011-07-01

    The accuracy of the measured excitation functions of nuclear reactions largely depend on the precise measurements of the exposed beam energy in activation experiment. We investigated the proton beam energy of the MC-50 cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS) employing the method natCu(p,xn)62Zn / natCu(p,xn)65Zn together with a stacked-foil activation technique. The beam energy along with the stacked samples was also theoretically calculated using computer program SRIM-2003. The measured beam energy showed generally a good agreement with the calculated ones, and this fact demonstrated that the energy (<30 MeV) of the proton beam could be determined by irradiating thin metallic Cu foil target with natural isotopic compositions. Hence, this may be considered as a useful technique for beam monitoring purposes in activation experiment.

  6. Low-Energy Run of Fermilab Electron Cooler's Beam Generation System

    SciTech Connect

    Prost, L.R.; Shemyakin, A.; Fedotov, A.; Kewisch, J.; /Brookhaven

    2011-03-14

    In the context of the evaluation of possibly using the Fermilab Electron Cooler for the proposed low-energy RHIC run at BNL, operating the cooler at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main conclusion of this feasibility study is that the cooler's beam generation system is suitable for BNL needs. The beam recirculation was stable for all tested parameters. In particular, a beam current of 0.38 A was achieved with the cathode magnetic field up to the maximum value presently available of 250 G. The energy ripple was measured to be 40 eV. A striking difference with running the 4.3 MeV beam (nominal for operation at FNAL) is that no unprovoked beam recirculation interruptions were observed. Electron cooling proposed to increase the luminosity of the RHIC collider for heavy ion beam energies below 10 GeV/nucleon [1] needs a good quality, 0.9-5 MeV electron beam. Preliminary design studies indicate that the scheme of the Recycler's electron cooler at FNAL is suitable for low-energy RHIC cooling and most parts of the cooler can be re-used after the end of the Tevatron Run II. To analyze issues related to the generation of the electron beam in the energy recovery mode and to gain experience with the beam transport at lower beam energy, a dedicated study was performed at FNAL with a beam run through a short beam line (so called U-bend). This report summarizes our findings and observations in the course of the measurements.

  7. Development of Ultra Small Shock Tube for High Energy Molecular Beam Source

    SciTech Connect

    Miyoshi, Nobuya; Nagata, Shuhei; Kinefuchi, Ikuya; Shimizu, Kazuya; Matsumoto, Yoichiro; Takagi, Shu

    2008-12-31

    A molecular beam source exploiting a small shock tube is described for potential generation of high energy beam in a range of 1-5 eV without any undesirable impurities. The performance of a non-diaphragm type shock tube with an inner diameter of 2 mm was evaluated by measuring the acceleration and attenuation process of shock waves. With this shock tube installed in a molecular beam source, we measured the time-of-flight distributions of shock-heated beams, which demonstrated the ability of controlling the beam energy with the initial pressure ratio of the shock tube.

  8. Low-energy run of Fermilab Electron Cooler's beam generation system

    SciTech Connect

    Prost, Lionel; Shemyakin, Alexander; Fedotov, Alexei; Kewisch, Jorg; /Brookhaven

    2010-08-01

    As a part of a feasibility study of using the Fermilab Electron Cooler for a low-energy Relativistic Heavy Ion Collider (RHIC) run at Brookhaven National Laboratory (BNL), the cooler operation at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main result of the study is that the cooler beam generation system is suitable for BNL needs. In a striking difference with running 4.3 MeV beam, no unprovoked beam recirculation interruptions were observed.

  9. Energy deposition studies for the LBNE beam absorber

    SciTech Connect

    Rakhno, Igor L.; Mokhov, Nikolai V.; Tropin, Igor S.

    2015-01-29

    Results of detailed Monte Carlo energy deposition studies performed for the LBNE absorber core and the surrounding shielding with the MARS15 code are described. The model of the entire facility, that includes a pion-production target, focusing horns, target chase, decay channel, hadron absorber system – all with corresponding radiation shielding – was developed using the recently implemented ROOT-based geometry option in the MARS15 code. This option provides substantial flexibility and automation when developing complex geometry models. Both normal operation and accidental conditions were studied. Various design options were considered, in particular the following: (i) filling the decay pipe with air or helium; (ii) the absorber mask material and shape; (iii) the beam spoiler material and size. Results of detailed thermal calculations with the ANSYS code helped to select the most viable absorber design options.

  10. Plunger lifetime measurements after Coulomb excitation at intermediate beam energies

    SciTech Connect

    Dewald, A.; Hackstein, M.; Rother, W.; Jolie, J.; Melon, B.; Pissulla, T.; Shimbara, Y.; Starosta, K.; Adrich, P.; Amthor, A. M.; Baumann, T.; Bazin, D.; Bowen, M.; Chester, A.; Dunomes, A.; Gade, A.; Galaviz, D.; Glasmacher, T.; Ginter, T.; Hausmann, M.

    2009-01-28

    Absolute transition probabilities of the first 2{sup +} state in {sup 110,114}Pd were remeasured using the recoil distance Doppler shift technique following projectile Coulomb excitation at intermediate beam energies for the first time. The {sup 110}Pd experiment served to check the novel technique as well as the method used for the data analysis which is based on the examination of {gamma}-ray lineshapes. Whereas the measured B(E2) value for {sup 110}Pd agrees very well with the literature, the value obtained for {sup 114}Pd differs considerably. The data is also used to test a novel concept, called the valence proton symmetry, which allows one to extrapolate nuclear properties to very neutron rich nuclei.

  11. Adventures in Gaseous Positronics - An Ultra-High-Energy-Resolution Cryogenic Beam

    NASA Astrophysics Data System (ADS)

    Natisin, Mike

    2016-05-01

    While positron interactions with matter are important in a variety of contexts, many important experiments have been inhibited due to the difficulties encountered in creating beams with narrow energy spreads. This talk focuses on the development of a pulsed positron beam with a total energy spread of 7 meV FWHM; this represents a factor of five improvement over the previous state-of-the-art. Current positron atomic physics experiments rely on high quality beams from buffer gas traps. Although widely used, the physical phenomena operative in beam formation had not previously been fully investigated, and understanding these processes proved crucial to improving beam quality. Experimental measurements and simulation results of positron cooling and beam formation are discussed, with an emphasis on beam energy resolution. Using these results, a new cryogenic, trap-based beam system was built. Positrons are cooled to 50 K using a CO buffer gas, resulting in beams with total energy spreads as low as 6.9 meV FWHM, sub-microsecond temporal spreads and beam diameters as small as 1 mm. Details of this beam system, as well as new experiments that will be enabled by it, will be discussed. Work supported by NSF Grant PHY-1401794.

  12. Focusing dynamics of high-energy density, laser-driven ion beams.

    PubMed

    Chen, S N; d'Humières, E; Lefebvre, E; Romagnani, L; Toncian, T; Antici, P; Audebert, P; Brambrink, E; Cecchetti, C A; Kudyakov, T; Pipahl, A; Sentoku, Y; Borghesi, M; Willi, O; Fuchs, J

    2012-02-01

    The dynamics of the focusing of laser-driven ion beams produced from concave solid targets was studied. Most of the ion beam energy is observed to converge at the center of the cylindrical targets with a spot diameter of 30  μm, which can be very beneficial for applications requiring high beam energy densities. Also, unbalanced laser irradiation does not compromise the focusability of the beam. However, significant filamentation occurs during the focusing, potentially limiting the localization of the energy deposition region by these beams at focus. These effects could impact the applicability of such high-energy density beams for applications, e.g., in proton-driven fast ignition. PMID:22400936

  13. Effects of surface and interface energies on the bending behavior of nanoscale multilayered beams

    NASA Astrophysics Data System (ADS)

    Wang, K. F.; Wang, B. L.

    2013-12-01

    A modified continuum model of the nanoscale multilayered beams is established by incorporating surface and interface energies. Through the principle of minimum potential energy, the governing equations and boundary conditions are obtained. The closed-form solutions are presented and the overall Young's modulus of the beam is studied. The surface and interface energies are found to have a major influence on the bending behavior and the overall Young's modulus of the beam. The effect of surface and interface energies on the overall Young's modulus depends on the boundary condition of the beam, the values of the surface/interface elasticity constants and the initial surface/interface energy of the system. The results can be used to guide the determinations of the surface/interface elasticity properties and the initial surface/interface energies of the nanoscale multilayered materials through nanoscale beam bending experiments.

  14. A method of predicting the energy-absorption capability of composite subfloor beams

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1987-01-01

    A simple method of predicting the energy-absorption capability of composite subfloor beam structure was developed. The method is based upon the weighted sum of the energy-absorption capability of constituent elements of a subfloor beam. An empirical data base of energy absorption results from circular and square cross section tube specimens were used in the prediction capability. The procedure is applicable to a wide range of subfloor beam structure. The procedure was demonstrated on three subfloor beam concepts. Agreement between test and prediction was within seven percent for all three cases.

  15. Characterization of the NEPOMUC primary and remoderated positron beams at different energies

    NASA Astrophysics Data System (ADS)

    Stanja, J.; Hergenhahn, U.; Niemann, H.; Paschkowski, N.; Sunn Pedersen, T.; Saitoh, H.; Stenson, E. V.; Stoneking, M. R.; Hugenschmidt, C.; Piochacz, C.

    2016-08-01

    We report on the characterization of the positron beam provided at the open beam port of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ) Garching. The absolute positron flux of the primary beam at 400 eV and 1 keV kinetic energy and of the remoderated beam at 5, 12 and 22 eV were determined. Energy-dependent intensities in the range of (1 - 5) ·108e+ / s and (2 - 6) ·107e+ / s have been observed for the primary and remoderated beam, respectively. We attribute the significant losses for the primary beam, in comparison with the expected value, to the non-adiabatic positron guiding in the beam line. We also measured the longitudinal energy distribution of the remoderated beam, yielding an energy spread below 3.3 eV. The mean transverse energy of the remoderated beam, determined from measurements in different final magnetic fields, was found to be below 1.3 eV. These results are likely to apply to the NEPOMUC beam delivered to other user stations.

  16. Experimental studies using a low-energy RI beam separator at CNS

    NASA Astrophysics Data System (ADS)

    Teranishi, T.; Kubono, S.; Shimoura, S.; Notani, M.; Yanagisawa, Y.; Michimasa, S.; Ue, K.; Iwasaki, H.; Kurokawa, M.; Satou, Y.; Morikawa, T.; Saito, A.; Baba, H.; Lee, J. H.; Lee, C. S.; Fülöp, Zs.; Kato, S.

    2003-05-01

    Radioactive-ion (RI) beams of 10C, 14O, 12N and 11C with energies low 10 A MeV were produced by using a low-energy in-flight RI beam separator newly constructed by CNS, University of Tokyo. Using the 12N and 11C beams, some resonance states were identified in the proton elastic scattering 12N+p and 11C+p, respectively.

  17. Surface modification of structural materials by low-energy high-current pulsed electron beam treatment

    SciTech Connect

    Panin, A. V. E-mail: kms@ms.tsc.ru; Kazachenok, M. S. E-mail: kms@ms.tsc.ru; Sinyakova, E. A.; Borodovitsina, O. M.; Ivanov, Yu. F.; Leontieva-Smirnova, M. V.

    2014-11-14

    Microstructure formation in surface layers of pure titanium and ferritic-martensitic steel subjected to electron beam treatment is studied. It is shown that low energy high-current pulsed electron beam irradiation leads to the martensite structure within the surface layer of pure titanium. Contrary, the columnar ferrite grains grow during solidification of ferritic-martensitic steel. The effect of electron beam energy density on the surface morphology and microstructure of the irradiated metals is demonstrated.

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

    SciTech Connect

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

    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.

  19. Design study of the Low Energy Beam Transport system at RISP

    NASA Astrophysics Data System (ADS)

    Bahng, Jungbae; Kim, Eunsan; Kim, Yonghwan; Hong, In-Seok

    2013-03-01

    We present the design status of LEBT for the RISP that consists of two 90 degree dipoles, a multi-harmonic buncher, pair solenoids, electrostatic quadrupoles and a high voltage platform. After ECR-IS with an energy of 10 keV/u, heavy-ion beams are selected by achromatic bending systems and then be bunched in the LEBT. A multi-harmonic buncher is used to achieve a small longitudinal emittance in the RFQ. We show the results on the optics design by using the TRANSPORT code and the beam tracking of two-charge beams by using the code IMPACT. We present the results and issues on beam dynamics simulaitons in the designed LEBT system. For heavy ion beams in the low energy system, we have to separate and select desire beam. we also transport beam from ECR to RFQ with high transmission.

  20. Beam performance and luminosity limitations in the high-energy storage ring (HESR)

    NASA Astrophysics Data System (ADS)

    Lehrach, A.; Boine-Frankenheim, O.; Hinterberger, F.; Maier, R.; Prasuhn, D.

    2006-06-01

    The high-energy storage ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an antiproton synchrotron storage ring in the momentum range 1.5-15 GeV/ c. An important feature of this new facility is the combination of phase space cooled beams and dense internal targets (e.g. pellet targets), which results in demanding beam parameter requirements for two operation modes: high luminosity mode with peak luminosities to 2×10 32 cm -2 s -1, and high-resolution mode with a momentum spread down to 10 -5. To reach these beam parameters one needs a very powerful phase space cooling, utilizing high-energy electron cooling and high-bandwidth stochastic cooling. The effects of beam-target scattering and intra-beam interaction are investigated in order to study beam equilibria and beam losses for the two different operation modes.

  1. Design and delivery of beam monitors for the energy-upgraded linac in J-PARC

    NASA Astrophysics Data System (ADS)

    Miura, Akihiko; Ouchi, Nobuo; Oguri, Hidetomo; Hasegawa, Kazuo; Miyao, Tomoaki; Ikegami, Masanori

    2015-02-01

    In the J-PARC (Japan Proton Accelerator Research Complex) linac, an energy-upgrade project has started to achieve a design beam power of 1 MW at the exit of the downstream synchrotron. To account for the significant beam parameter upgrades, we will use the newly-fabricated beam monitors for the beam commissioning. This paper discusses the design and assembly of the beam position monitor, phase monitor, current monitor, transverse profile monitor, and beam loss monitor for the energy-upgraded linac. We periodically installed the newly-fabricated monitors for the upgraded beam line, as well as for longitudinal matching, because of the frequency jump between the original RF cavity and the newly-developed cavity. We employed two debunchers to correct for momentum spread and jitter. To account for the new debunchers, we fabricated and installed additional pairs of phase monitors in order to tune the debunchers to the adequate RF set point. Finally, we propose commissioning plans to support the beam monitor check. We will begin to establish the 181-MeV operation to confirm the proper functioning of beam monitors. Herein, we will examine the response to changes of the knobs that control the quadrupole magnets after the energy upgrade. After proper functioning of the beam monitors is confirmed, we will use the new beam monitors to establish the 400-MeV acceleration operation.

  2. Beam losses and beam halos in accelerators for new energy sources

    SciTech Connect

    Jameson, R.A.

    1995-12-31

    Large particle accelerators are proposed as drivers for new ways to produce electricity from nuclear fusion and fission reactions. The accelerators must be designed to deliver large particle beam currents to a target facility with very little beam spill along the accelerator itself, in order that accelerator maintenance can be accomplished without remote manipulators. Typically, particle loss is preceded by the formation of a tenuous halo of particles around the central beam core, caused by beam dynamics effects, often coupled with the slight imperfections inevitable in a practical design. If the halo becomes large enough, particles may be scraped off along the accelerator. The tolerance for beam spill in different applications is discussed, halo mechanisms and recent work to explore and understand their dynamics are reviewed, and possible directions for future investigation are outlined. 17 refs., 10 figs.

  3. Influence of initial energy modulation on premodulated electron beam propagating through a drift tube

    SciTech Connect

    Uhm, H.S.

    1997-09-01

    Influence of the initial energy modulation caused by the self-potential depression on the premodulated electron-beam propagation through a drift tube is investigated. The potential depression {kappa} can significantly vary because of the initial current modulation. Thus, beam{close_quote}s kinetic energy at the injection varies accordingly. A self-consistent nonlinear theory of current modulation of the premodulated electron beam is developed. It is shown that the initial energy modulation caused by the self-potential depression at injection plays a significant role in the current modulation for long range propagation. It is also found from a small signal theory that reduction of the beam{close_quote}s kinetic energy due to its potential depression accelerates debunching process of the initial current modulation. Although the initial current modulation is debunched quickly for high current beam, amplitude of the current modulation never becomes zero because of the initial energy modulation. {copyright} {ital 1997 American Institute of Physics.}

  4. Low-Energy Plasma Focus Device as an Electron Beam Source

    PubMed Central

    Seong Ling, Yap; Naresh Kumar, Nitturi; Lian Kuang, Lim; Chiow San, Wong

    2014-01-01

    A low-energy plasma focus device was used as an electron beam source. A technique was developed to simultaneously measure the electron beam intensity and energy. The system was operated in Argon filling at an optimum pressure of 1.7 mbar. A Faraday cup was used together with an array of filtered PIN diodes. The beam-target X-rays were registered through X-ray spectrometry. Copper and lead line radiations were registered upon usage as targets. The maximum electron beam charge and density were estimated to be 0.31 μC and 13.5 × 1016/m3, respectively. The average energy of the electron beam was 500 keV. The high flux of the electron beam can be potentially applicable in material sciences. PMID:25544952

  5. High-Energy Laser-Accelerated Electron Beams for Long-Range Interrogation

    SciTech Connect

    Cummingham, N. J.; Banerjee, Sudeep; Ramanathan, Vidya; Powell, Nathan; Chandler-Smith, Nate; Vane, C Randy; Schultz, David Robert; Pozzi, Sara; Clarke, Shaun; Beene, James R; Umstadter, Donald

    2009-01-01

    We are studying the use of 0.1 1.0 GeV laser-accelerated electron beams as active interrogation probes for long-standoff radiography or nuclear activation of concealed special nuclear material. Use of beams in this energy range is largely unexplored, but such beams could provide notable advantages over lower-energy beams and x-rays. High-energy laser-accelerated electrons exhibit large penetration range through air and solids, and low beam divergence for both direct beams and secondary Bremsstrahlung x-rays. We present laboratory measurements of radiography and activation, using the high-power Diodes laser system at the University of Nebraska, as well as MCNP and GEANT Monte Carlo simulation results used to aid experiment design and interpretation.

  6. Executive Summary of the Workshop on Polarization and Beam Energy Measurements at the ILC

    SciTech Connect

    Aurand, B.; Bailey, I.; Bartels, C.; Blair, G.; Brachmann, A.; Clarke, J.; Deacon, L.; Duginov, V.; Ghalumyan, A.; Hartin, A.; Hauptman, J.; Helebrant, C.; Hesselbach, S.; Kafer, D.; List, J.; Lorenzon, W.; Lyapin, A.; Marchesini, I.; Melikian, R.; Monig, K.; Moeit, K.C.; /Bonn U. /Cockcroft Inst. Accel. Sci. Tech. /DESY /DESY, Zeuthen /Royal Holloway, U. of London /SLAC /Daresbury /Dubna, JINR /Yerevan Phys. Inst /Oxford U., JAI /Iowa State U. /Durham U., IPPP /Michigan U. /University Coll. London /Novosibirsk, IYF /Minsk, Inst. Phys. /Oregon U.

    2008-07-25

    This note summarizes the results of the 'Workshop on Polarization and Beam Energy Measurements at the ILC', held at DESY (Zeuthen) April 9-11 2008. The topics for the workshop included (1) physics requirements, (2) polarized sources and low energy polarimetry, (3) BDS polarimeters, (4) BDS energy spectrometers, and (5) physics-based measurements of beam polarization and beam energy from collider data. Discussions focused on the current ILC baseline program as described in the Reference Design Report (RDR), which includes physics runs at beam energies between 100 and 250 GeV, as well as calibration runs on the Z-pole. Electron polarization of P{sub e{sup -}} {approx}> 80% and positron polarization of P{sub e{sup +}} {approx}> 30% are part of the baseline configuration of the machine. Energy and polarization measurements for ILC options beyond the baseline, including Z-pole running and the 1 TeV energy upgrade, were also discussed.

  7. Parametric Channeling Radiation and its Application to the Measurement of Electron Beam Energy

    SciTech Connect

    Takabayashi, Y.

    2010-06-23

    We have proposed a method for observing parametric channeling radiation (PCR) and of applying it to the measurement of electron beam energy. The PCR process occurs if the energy of the channeling radiation coincides with the energy of the parametric X-ray radiation (PXR). The PCR process can be regarded as the diffraction of 'virtual channeling radiation'. We developed a scheme for beam energy measurement and designed an experimental setup. We also estimated the beam parameters, and calculated the angular distributions of PXR and PCR. These considerations indicate that the observation of PCR is promising.

  8. FEL and Optical Klystron Gain for an Electron Beam with Oscillatory Energy Distribution

    SciTech Connect

    Stupakov, G.; Ding, Y.; Huang, Z.; /SLAC

    2009-12-09

    If the energy spread of a beam is larger then the Pierce parameter, the FEL gain length increases dramatically and the FEL output gets suppressed. We show that if the energy distribution of such a beam is made oscillatory on a small scale, the gain length can be considerably decreased. Such an oscillatory energy distribution is generated by first modulating the beam energy with a laser via the mechanism of inverse FEL, and then sending it through a strong chicane. We show that this approach also works for the optical klystron enhancement scheme. Our analytical results are corroborated by numerical simulations.

  9. Advanced Beam Energy Spread Monitoring Systems and Their Control at Jefferson Lab

    SciTech Connect

    Pavel Chevtsov

    2005-03-01

    Two Synchrotron Light Interferometers (SLI) have been in use at Jefferson Lab for more than one year. Each SLI is an absolutely not invasive beam diagnostic device routinely monitoring the transverse beam size and beam energy spread in a wide range of beam energies and intensities with a very high accuracy. The SLI are automated with the use of distributed, multi-level, and multi-component control software. The paper describes the SLI configuration, the structure of the SLI control software and its performance.

  10. A microstructure- and surface energy-dependent third-order shear deformation beam model

    NASA Astrophysics Data System (ADS)

    Gao, X.-L.; Zhang, G. Y.

    2015-08-01

    A new non-classical third-order shear deformation model is developed for Reddy-Levinson beams using a variational formulation based on Hamilton's principle. A modified couple stress theory and a surface elasticity theory are employed. The equations of motion and complete boundary conditions for the beam are obtained simultaneously. The new model contains a material length scale parameter to account for the microstructure effect and three surface elastic constants to describe the surface energy effect. Also, Poisson's effect is incorporated in the new beam model. The current non-classical model recovers the classical elasticity-based third-order shear deformation beam model as a special case when the microstructure, surface energy and Poisson's effects are all suppressed. In addition, the newly developed beam model includes the models considering the microstructure dependence or the surface energy effect alone as limiting cases and reduces to two existing models for Bernoulli-Euler and Timoshenko beams incorporating the microstructure and surface energy effects. To illustrate the new model, the static bending and free vibration problems of a simply supported beam loaded by a concentrated force are analytically solved by directly applying the general formulas derived. For the static bending problem, the numerical results reveal that both the deflection and rotation of the simply supported beam predicted by the current model are smaller than those predicted by the classical model. Also, it is observed that the differences in the deflection and rotation predicted by the two beam models are very large when the beam thickness is sufficiently small, but they are diminishing with the increase in the beam thickness. For the free vibration problem, it is found that the natural frequency predicted by the new model is higher than that predicted by the classical beam model, and the difference is significant for very thin beams. These predicted trends of the size effect at the

  11. Development of an energy selector system for laser-driven proton beam applications

    NASA Astrophysics Data System (ADS)

    Scuderi, V.; Bijan Jia, S.; Carpinelli, M.; Cirrone, G. A. P.; Cuttone, G.; Korn, G.; Licciardello, T.; Maggiore, M.; Margarone, D.; Pisciotta, P.; Romano, F.; Schillaci, F.; Stancampiano, C.; Tramontana, A.

    2014-03-01

    Nowadays, laser-driven proton beams generated by the interaction of high power lasers with solid targets represent a fascinating attraction in the field of the new acceleration techniques. These beams can be potentially accelerated up to hundreds of MeV and, therefore, they can represent a promising opportunity for medical applications. Laser-accelerated proton beams typically show high flux (up to 1011 particles per bunch), very short temporal profile (ps), broad energy spectra and poor reproducibility. In order to overcome these limitations, these beams have be controlled and transported by means of a proper beam handling system. Furthermore, suitable dosimetric diagnostic systems must be developed and tested. In the framework of the ELIMED project, we started to design a dedicated beam transport line and we have developed a first prototype of a beam line key-element: an Energy Selector System (ESS). It is based on permanent dipoles, capable to control and select in energy laser-accelerated proton beams. Monte Carlo simulations and some preliminary experimental tests have been already performed to characterize the device. A calibration of the ESS system with a conventional proton beam will be performed in September at the LNS in Catania. Moreover, an experimental campaign with laser-driven proton beam at the Centre for Plasma Physics, Queens University in Belfast is already scheduled and will be completed within 2014.

  12. Global energy confinement scaling for neutral-beam-heated tokamaks

    SciTech Connect

    Kaye, S.M.; Goldston, R.J.

    1984-10-01

    A total of 677 representative discharges from seven neutral-beam-heated tokamaks has been used to study the parametric scaling of global energy confinement time. Contributions to this data base were from ASDEX, DITE, D-III, ISX-B, PDX, PLT, and TFR, and were taken from results of gettered, L-mode type discharges. Assuming a power law dependence of tau/sub E/ on discharge parameters kappa, I/sub p/, B/sub t/, anti n/sub e/ P/sub tot/, a, and R/a, standard multiple linear regression techniques were used in two steps to determine the scaling. The results indicate that the discharges used in the study are well described by the scaling tau/sub E/ ..cap alpha.. kappa/sup 0.28/ B/sub T//sup -0.09/ I/sub p//sup 1.24/anti n/sub e//sup -0.26/ P/sub tot//sup -0.58/ a/sup 1.16/ (R/a)/sup 1.65/.

  13. Beam manipulation techniques, nonlinear beam dynamics, and space charge effect in high energy high power accelerators

    SciTech Connect

    Lee, S. Y.

    2014-04-07

    We had carried out a design of an ultimate storage ring with beam emittance less than 10 picometer for the feasibility of coherent light source at X-ray wavelength. The accelerator has an inherent small dynamic aperture. We study method to improve the dynamic aperture and collective instability for an ultimate storage ring. Beam measurement and accelerator modeling are an integral part of accelerator physics. We develop the independent component analysis (ICA) and the orbit response matrix method for improving accelerator reliability and performance. In collaboration with scientists in National Laboratories, we also carry out experimental and theoretical studies on beam dynamics. Our proposed research topics are relevant to nuclear and particle physics using high brightness particle and photon beams.

  14. A new beam loss detector for low-energy proton and heavy-ion accelerators

    NASA Astrophysics Data System (ADS)

    Liu, Zhengzheng; Crisp, Jenna; Russo, Tom; Webber, Robert; Zhang, Yan

    2014-12-01

    The Facility for Rare Isotope Beams (FRIB) to be constructed at Michigan State University shall deliver a continuous, 400 kW heavy ion beam to the isotope production target. This beam is capable of inflicting serious damage on accelerator components, e.g. superconducting RF accelerating cavities. A Beam Loss Monitoring (BLM) System is essential for detecting beam loss with sufficient sensitivity and promptness to inform the machine protection system (MPS) and operations personnel of impending dangerous losses. Radiation transport simulations reveal shortcomings in the use of ionization chambers for the detection of beam losses in low-energy, heavy-ion accelerators. Radiation cross-talk effects due to the folded geometry of the FRIB LINAC pose further complications to locating specific points of beam loss. We propose a newly developed device, named the Loss Monitor Ring (LMR1

  15. Nuclear Astrophysics and Structure Studies Using Low-energy RI Beams at CRIB

    SciTech Connect

    Yamaguchi, H.; Hashimoto, T.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kubono, S.

    2010-05-12

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Using the RI beams at CRIB, Many measurements on proton and alpha resonance scatterings, (alpha,p) reactions, and others were peformed in recent years, mainly for studying astrophysical reactions and exotic nuclear structure. Among them, the results on the {sup 7}Be+p and {sup 7}Li+alpha resonance scatterings are presented.

  16. Nuclear Astrophysics and Structure Studies Using Low-energy RI Beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Hashimoto, T.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kubono, S.

    2010-05-01

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Using the RI beams at CRIB, Many measurements on proton and alpha resonance scatterings, (α,p) reactions, and others were peformed in recent years, mainly for studying astrophysical reactions and exotic nuclear structure. Among them, the results on the 7Be+p and 7Li+α resonance scatterings are presented.

  17. The production of low-energy neutral oxygen beams by grazing-incidence neutralization

    NASA Technical Reports Server (NTRS)

    Albridge, R. G.; Haglund, R. F.; Tolk, N. H.; Daech, A. F.

    1987-01-01

    The Vanderbilt University neutral oxygen facility produces beams of low-energy neutral oxygen atoms by means of grazing-incidence collisions between ion beams and metal surfaces. Residual ions are reflected by applied electric fields. This method can utilize initial ion beams of either O(+) or O2(+) since a very large percentage of molecular oxygen ions are dissociated when they undergo grazing-incidence neutralization. The method of neutralization is applicable to low-energy beams and to all ions. Particular emphasis is on O and N2 beams for simulation of the low Earth orbit space environment. Since the beam is a pure O-neutral beam and since measurements of the interaction of the beam with solid surfaces are made spectroscopically, absolute reaction rates can be determined. The technique permits the beams to be used in conjunction with electron and photon irradiation for studies of synergistic effects. Comparisons of optical spectra of Kapton excited by 2.5-keV O, O(+), and O2(+) show significant differences. Optical spectra of Kapton excited by neutral oxygen beams of less than 1 keV have been recorded.

  18. Energy transfer between laser beams due to recording of optical axis gratings in liquid crystals

    NASA Astrophysics Data System (ADS)

    Nersisyan, Sarik R.; Tabiryan, Nelson V.; Stickley, C. Martin

    2006-10-01

    We have studied two-beam-coupling processes related to the generation of optical axis gratings in liquid crystals (LCs) due to the electromagnetic torque acting on the orientation of LCs in superimposed laser beams with spatially modulated polarization. Such gratings result in efficient coupling between the laser beams controlled by the frequency shift introduced between the beams at infrasound frequencies. Larger than 80% efficiency of energy transfer from a pump to a signal beam is reported at power density levels of the laser beams at 1-10 kW/cm2. The distinction between pump and signal beams is relative, since the sign of the frequency shift rather than the power ratio between the beams determines the direction of energy transfer. The experiments were performed for radiation at a 1.06 μm wavelength; high optical nonlinearity and low absorption make LCs suitable for use in visible and near-IR spectra, particularly in high-power laser systems. We have characterized the main fundamental features of the process of recording dynamic orientation gratings, plotting the gain spectra for several LCs and verifying the good quality of the amplified signal beam even for a strongly distorted pump. The obtained results set the groundwork for a variety of novel opportunities and applications that include combining high-power laser beams and wavelength division multiplexing at an ultranarrow interval of frequencies of the order of 1-100 Hz.

  19. Beam energy spread in FERMI@elettra gun and linac induced by intrabeam scattering

    SciTech Connect

    Zholents, Alexander A; Zholents, Alexander A; Zolotorev, Max S.; Penco, Giuseppe

    2008-07-11

    Intrabeam scattering (IBS) of electrons in the pre-cathode area in the electron guns know in the literature as Boersh effect is responsible for a growth of the electron beam energy spread there. Albeit most visible within the electron gun where the electron beam density is large and the energy spread is small, the IBS acts all along the entire electron beam pass through the Linac. In this report we calculate the energy spread induced by IBS in the FERMI@elettra electron gun.

  20. Non-Gaussian beam dynamics in low energy antiproton storage rings

    NASA Astrophysics Data System (ADS)

    Resta-López, J.; Hunt, J. R.; Welsch, C. P.

    2016-10-01

    In low energy antiproton facilities, where electron cooling is fundamental, the cooling forces together with heating phenomena causing emittance blow-up, such as Intra Beam Scattering (IBS), result in highly non-Gaussian beam distributions. In these cases, a precise simulation of IBS effects is essential to realistically evaluate the long term beam evolution, taking into account the non-Gaussian characteristics of the beam. Here, we analyse the beam dynamics in the Extra Low ENergy Antiproton ring (ELENA), which is a new small synchrotron currently being constructed at CERN to decelerate antiprotons to energies as low as 100 keV. Simulations are performed using the code BETACOOL, comparing different models of IBS.

  1. Two beam energy exchange in hybrid liquid crystal cells with photorefractive field controlled boundary conditions

    NASA Astrophysics Data System (ADS)

    Reshetnyak, V. Yu.; Pinkevych, I. P.; Subota, S. I.; Evans, D. R.

    2016-09-01

    We develop a theory describing energy gain when two light beams intersect in a hybrid nematic liquid crystal (LC) cell with photorefractive crystalline substrates. A periodic space-charge field induced by interfering light beams in the photorefractive substrates penetrates into the LC layer and reorients the director. We account for two main mechanisms of the LC director reorientation: the interaction of the photorefractive field with the LC flexopolarization and the director easy axis at the cell boundaries. It is shown that the resulting director grating is a sum of two in-phase gratings: the flexoelectric effect driven grating and the boundary-driven grating. Each light beam diffracts from the induced gratings leading to an energy exchange between beams. We evaluate the signal beam gain coefficient and analyze its dependence on the director anchoring energy and the magnitude of the director easy axis modulation.

  2. Neutralization of Space Charge Effects for Low Energy Ion Beams Using Field Emitters

    SciTech Connect

    Nicolaescu, D.; Sakai, S.; Matsuda, K.; Gotoh, Y.; Ishikawa, J.

    2008-11-03

    The paper presents models and computations for neutralization of space charge effects using electrons provided by field emitter arrays. Different ion species ({sup 11}B{sup +},{sup 31}P{sup +},{sup 75}As{sup +}) with energy in the range E{sub ion} = 200 eV-1 keV have been considered. The ion beam divergence is studied as a function of electron beam geometry and physical parameters (electron and ion energy, electron/ion current ratio I{sub el}/I{sub ion}). The electron beam geometry takes into account electron source positions and initial launching angles. It is shown that optimal ion beam neutralization occurs for low energy electrons emitted parallel to the ion beam.

  3. Performance Studies of the Vibration Wire Monitor on the Test Stand with Low Energy Electron Beam

    NASA Astrophysics Data System (ADS)

    Okabe, Kota; Yoshimoto, Masahiro; Kinsho, Michikazu

    In the high intensity proton accelerator as the Japan Proton Accelerator Research Complex (J-PARC) accelerators, serious radiation and residual dose is induced by a small beam loss such a beam halo. Therefore, diagnostics of the beam halo formation is one of the most important issues to control the beam loss. For the beam halo monitor, the vibration wire monitor (VWM) has a potential for investigating the beam halo and weak beam scanning. The VWM has a wide dynamic range, high resolution and the VWM is not susceptible to secondary electrons and electric noises. We have studied the VWM features as a new beam-halo monitor on the test stand with low energy electron gun. The frequency shift of the irradiated vibration wire was confirmed about wire material and the electron beam profile measured by using the VWM was consistent with the results of the Faraday cup measurement. Also we calculated a temperature distribution on the vibration wire which is irradiated by the electron beam with the numerical simulation. The simulations have been fairly successful in reproducing the transient of the irradiated vibration wire frequency measured by test stand experiments. In this paper, we will report a result of performance evaluation for the VWM on the test stands and discuss the VWM for beam halo diagnostic

  4. A simulation study on energy recovery from spent electron beams in an S-band linac

    NASA Astrophysics Data System (ADS)

    Masuda, K.; Matsumura, S.; Kii, T.; Ohgaki, H.; Yamazaki, T.; Nagasaki, K.; Yoshikawa, K.

    2003-07-01

    The feasibility of energy recovery with an S-band linac was studied based on two-dimensional particle-in-cell simulations. A 1-m standing-wave accelerating tube with 20 cells was chosen for the numerical model, with a 4.5-cell RF gun as the injector which is to be used for our IR FEL project. For ample reduction of beam energy to the dump with a typical beam energy from the gun of 5.49 MeV, the phase acceptance of the re-injection of the spent beam is found to be ±0.16 π rad which corresponds to a feasible longitudinal deviation of ±27 ps. Furthermore, for a lower beam energy to the dump and a higher wall plug efficiency, simulations with a lower beam energy of 2.42 MeV from the gun were carried out. Counter re-injection of the spent beam is found to be effective for compensating longitudinal velocity variations of low-energy beams along the tube, while degradation in the transverse emittance due to enhanced space-charge effect was found.

  5. Electron beam guiding by grooved SiO{sub 2} parallel plates without energy loss

    SciTech Connect

    Xue, Yingli; Yu, Deyang Liu, Junliang; Zhang, Mingwu; Yang, Bian; Zhang, Yuezhao; Cai, Xiaohong

    2015-12-21

    Using a pair of grooved SiO{sub 2} parallel plates, stably guided electron beams were obtained without energy loss at 800–2000 eV. This shows that the transmitted electrons are guided by a self-organized repulsive electric field, paving the way for a self-adaptive manipulation of electron beams.

  6. Ion beam energy deposition physics for ICF targets

    SciTech Connect

    Mehlhorn, T.A.

    1980-01-01

    The target interaction physics of light ion beams will be described. The phenomenon of range shortening with increasing material temperature will be corroborated, and the concomittant phenomenon of range relengthening due to ion-electron decoupling will be introduced.

  7. STOCHASTIC COOLING OF HIGH-ENERGY BUNCHED BEAMS

    SciTech Connect

    BLASKIEWICZ,M.; BRENNAN, J.M.

    2007-06-25

    Stochastic cooling of 100 GeV/nucleon bunched beams has been achieved in the Relativistic Heavy Ion Collider (RHIC). The physics and technology of the longitudinal cooling system are discussed, and plans for a transverse cooling system are outlined.

  8. A detector to measure transverse profiles and energy of an H- beam using gas stripping and laser photo neutralization

    NASA Astrophysics Data System (ADS)

    Connolly, R.; Degen, C.; DeSanto, L.; Raparia, D.

    2012-02-01

    A detector has been developed at Brookhaven National Lab (BNL) [1] and installed in the exit beam line of the BNL H- linear accelerator (linac) to measure transverse beam profiles, average beam energy and beam-energy spread. These beam properties are found by deflecting beam electrons, produced by both gas stripping and laser neutralization, into a detector. An H- ion, with a first ionization potential of 0.756 eV, can be neutralized by collisions with background gas and by absorbing the energy of a photon of wavelength shorter than 1.64 m. Free electrons produced by both mechanisms are deflected out of the H- beam by a dipole magnet and into a chamber which measures electron charge vs. energy. Ion-beam profiles are measured by scanning a laser beam across the H- beam and measuring the laser-stripped electron charge vs. laser position. Beam energy is deduced by measuring either the laser-stripped or gas-stripped electron charge which passes through a retarding-voltage grid vs. the grid voltage. Since beam electrons have the same velocities as beam protons, the beam proton energy is the electron energy multiplied by mp/me=1836, [E=(γ-1)mc2].

  9. Control of beam dynamics in high energy induction linacs

    SciTech Connect

    Caporaso, G.J.

    1986-07-29

    The Advent of laser-ion-guiding in the Advanced test Accelerator along with the development of accelerator cavities optimized with respect to beam breakup coupling impedence now make it possible to consider a new class of high current, high emergy linear induction accelerators. The control of the beam breakup and other instabilities by laser guiding and by various magnetic focusing schemes will be discussed along with the scaling laws for the design of such machines to minimize the growth of the beam breakup instability. Many linacs, particularly induction linacs are limited in performance by the beam breakup (BBU) instability. The instability is found in two forms. In the first form the accelerating cavities communicate with one another through interaction with the beam and through propagation of cavity fields through the accelerator structure. In the second form which is the more virulent of the two, the cavities couple to each other only through their interactions with the beam. It is this second form of PPU that will be discussed in this paper.

  10. Beam Test of Multi-Bunch Energy Compensation System in the Accelerator Test Facility at KEK

    NASA Astrophysics Data System (ADS)

    Kashiwagi, Shigeru; Hayano, Hitoshi; Kubo, Kiyoshi; Korhonen, Timo; Nakamura, Shogo; Naito, Takashi; Oide, Katsunobu; Takeda, Seishi; Terunuma, Nobuhiro; Urakawa, Junji

    2004-08-01

    A beam test of the multi-bunch energy compensation system (ECS) was performed using the Δ F method with the 2856± 4.327 MHz accelerating structures in the accelerator test facility (ATF) at KEK. The 1.54 GeV S-band linac of the ATF was designed to accelerate a multi-bunch beam that consists of 20 bunches with 2.8 ns spacing. The multi-bunch beam with 2.0× 1010 electrons/bunch has an energy deviation of about 8.5% at the end of the linac due to transient beam loading without ECS. The ATF linac is the injector of the ATF damping ring (DR), whose energy acceptance is ± 0.5%. The beam loading compensation system is necessary in the ATF linac for the successful injection of multi-bunch into DR. The rf system of the linac consists of 8 regular rf units with the SLED system and 2 ECS rf units without the SLED system. The accelerating structures of the regular units are driven at 2856 MHz and the 2 ECS structures are operated with slightly different rf frequencies of 2856± 4.327 MHz. In the beam test, we have succeeded in compressing the multi-bunch energy spread within the energy acceptance of the DR using Δ F ECS. The principle of the beam loading compensation system of KEK-ATF and the experimental results are described in this paper.

  11. High-flux source of low-energy neutral beams using reflection of ions from metals

    NASA Technical Reports Server (NTRS)

    Cuthbertson, John W.; Motley, Robert W.; Langer, William D.

    1992-01-01

    Reflection of low-energy ions from surfaces can be applied as a method of producing high-flux beams of low-energy neutral particles, and is an important effect in several areas of plasma technology, such as in the edge region of fusion devices. We have developed a beam source based on acceleration and reflection of ions from a magnetically confined coaxial RF plasma source. The beam provides a large enough flux to allow the energy distribution of the reflected neutrals to be measured despite the inefficiency of detection, by means of an electrostatic cylindrical mirror analyzer coupled with a quadrupole mass spectrometer. Energy distributions have been measured for oxygen, nitrogen, and inert gas ions incident with from 15 to 70 eV reflected from amorphous metal surfaces of several compositions. For ions of lighter atomic mass than the reflecting metal, reflected beams have peaked energy distributions; beams with the peak at 4-32 eV have been measured. The energy and mass dependences of the energy distributions as well as measurements of absolute flux, and angular distribution and divergence are reported. Applications of the neutral beams produced are described.

  12. Proposal for continuously-variable neutrino beam energy for the NuMI facility

    SciTech Connect

    Kostin, Mikhail; Kopp, Sacha; Messier, Mark; Harris, Deborah A.; Hylen, Jim; Para, Adam; /Fermilab

    2006-07-01

    The NuMI Facility was intended to be flexibly changed between 3 energies of beams, LE, ME, and HE. However, the changeover requires extensive downtime to move and realign horns and the target. We propose to implement a flexible arrangement where the target can be remotely moved in the beamline direction to change the beam energy and the horns remain fixed. In addition to having the attractive feature of keeping the horn optics fixed, the motion of the target can be performed more quickly and hence on a more frequent basis. We discuss potential increases in statistics in the high energy region, systematic cross-checks available, and the improved beam monitoring capabilities with such variable energy beams.

  13. Extraction characteristics of a low-energy ion beam system with a remote plasma chamber

    NASA Astrophysics Data System (ADS)

    Vasquez, M. R.; Wada, M.

    2016-02-01

    Low-energy argon beams were extracted from a dual-chamber ion source system. The first chamber is a quartz cylinder where dense inductively coupled plasmas were produced using 13.56 MHz radio frequency (rf) power. The discharge was driven into an adjacent chamber which acts as a reservoir for ion beam extraction using a dual-electrode extractor configuration. Extraction of ions from the second chamber with energies in the 100 eV range was achieved while minimizing fluctuations induced by the rf signal. A custom-built retarding potential analyzer was used to analyze the effectiveness of ion beam transport using the remote plasma chamber. Well-defined beams were extracted between 60 and 100 V extraction potentials at 50-100 W rf powers. An increase in rf power resulted in an increase in average ion energy, increase in ion current density while the energy spread remains constant.

  14. Microwave and Beam Activation of Nanostructured Catalysts for Environmentally Friendly, Energy Efficient Heavy Crude Oil Processing

    SciTech Connect

    2009-03-01

    This factsheet describes a study whose goal is initial evaluation and development of energy efficient processes which take advantage of the benefits offered by nanostructured catalysts which can be activated by microwave, RF, or radiation beams.

  15. Chromaticity of the lattice and beam stability in energy-recovery linacs

    SciTech Connect

    Litvinenko, V.N.

    2011-12-23

    Energy recovery linacs (ERLs) are an emerging generation of accelerators promising to revolutionize the fields of high-energy physics and photon sciences. These accelerators combine the advantages of linear accelerators with that of storage rings, and hold the promise of delivering electron beams of unprecedented power and quality. Use of superconducting radio-frequency (SRF) cavities converts ERLs into nearly perfect 'perpetuum mobile' accelerators, wherein the beam is accelerated to a desirable energy, used, and then gives the energy back to the RF field. One potential weakness of these devices is transverse beam break-up instability that could severely limit the available beam current. In this paper, I present a method of suppressing these dangerous effects using a natural phenomenon in the accelerators, viz., the chromaticity of the transverse motion.

  16. Precision shape modification of nanodevices with a low-energy electron beam

    DOEpatents

    Zettl, Alex; Yuzvinsky, Thomas David; Fennimore, Adam

    2010-03-09

    Methods of shape modifying a nanodevice by contacting it with a low-energy focused electron beam are disclosed here. In one embodiment, a nanodevice may be permanently reformed to a different geometry through an application of a deforming force and a low-energy focused electron beam. With the addition of an assist gas, material may be removed from the nanodevice through application of the low-energy focused electron beam. The independent methods of shape modification and material removal may be used either individually or simultaneously. Precision cuts with accuracies as high as 10 nm may be achieved through the use of precision low-energy Scanning Electron Microscope scan beams. These methods may be used in an automated system to produce nanodevices of very precise dimensions. These methods may be used to produce nanodevices of carbon-based, silicon-based, or other compositions by varying the assist gas.

  17. Undulator-Based Laser Wakefield Accelerator Electron Beam Energy Spread and Emittance Diagnostic

    SciTech Connect

    Bakeman, M.S.; Van Tilborg, J.; Nakamura, K.; Gonsalves, A.; Osterhoff, J.; Sokollik, T.; Lin, C.; Robinson, K.E.; Schroeder, C.B.; Toth, Cs.; Weingartner, R.; Gruner, F.; Esarey, E.; Leemans, W.P.

    2010-06-01

    The design and current status of experiments to couple the Tapered Hybrid Undulator (THUNDER) to the Lawrence Berkeley National Laboratory (LBNL) laser plasma accelerator (LPA) to measure electron beam energy spread and emittance are presented.

  18. Neutrons in proton pencil beam scanning: parameterization of energy, quality factors and RBE

    NASA Astrophysics Data System (ADS)

    Schneider, Uwe; Hälg, Roger A.; Baiocco, Giorgio; Lomax, Tony

    2016-08-01

    The biological effectiveness of neutrons produced during proton therapy in inducing cancer is unknown, but potentially large. In particular, since neutron biological effectiveness is energy dependent, it is necessary to estimate, besides the dose, also the energy spectra, in order to obtain quantities which could be a measure of the biological effectiveness and test current models and new approaches against epidemiological studies on cancer induction after proton therapy. For patients treated with proton pencil beam scanning, this work aims to predict the spatially localized neutron energies, the effective quality factor, the weighting factor according to ICRP, and two RBE values, the first obtained from the saturation corrected dose mean lineal energy and the second from DSB cluster induction. A proton pencil beam was Monte Carlo simulated using GEANT. Based on the simulated neutron spectra for three different proton beam energies a parameterization of energy, quality factors and RBE was calculated. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed parameterizations in order to calculate the spatially localized neutron energy, quality factors and RBE for each treated patient. The parameterization represents the simple quantification of neutron energy in two energy bins and the quality factors and RBE with a satisfying precision up to 85 cm away from the proton pencil beam when compared to the results based on 3D Monte Carlo simulations. The root mean square error of the energy estimate between Monte Carlo simulation based results and the parameterization is 3.9%. For the quality factors and RBE estimates it is smaller than 0.9%. The model was successfully integrated into the PSI treatment planning system. It was found that the parameterizations for neutron energy, quality factors and RBE were independent of proton energy in the investigated energy range of interest for proton therapy. The pencil beam algorithm has

  19. Neutrons in proton pencil beam scanning: parameterization of energy, quality factors and RBE.

    PubMed

    Schneider, Uwe; Hälg, Roger A; Baiocco, Giorgio; Lomax, Tony

    2016-08-21

    The biological effectiveness of neutrons produced during proton therapy in inducing cancer is unknown, but potentially large. In particular, since neutron biological effectiveness is energy dependent, it is necessary to estimate, besides the dose, also the energy spectra, in order to obtain quantities which could be a measure of the biological effectiveness and test current models and new approaches against epidemiological studies on cancer induction after proton therapy. For patients treated with proton pencil beam scanning, this work aims to predict the spatially localized neutron energies, the effective quality factor, the weighting factor according to ICRP, and two RBE values, the first obtained from the saturation corrected dose mean lineal energy and the second from DSB cluster induction. A proton pencil beam was Monte Carlo simulated using GEANT. Based on the simulated neutron spectra for three different proton beam energies a parameterization of energy, quality factors and RBE was calculated. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed parameterizations in order to calculate the spatially localized neutron energy, quality factors and RBE for each treated patient. The parameterization represents the simple quantification of neutron energy in two energy bins and the quality factors and RBE with a satisfying precision up to 85 cm away from the proton pencil beam when compared to the results based on 3D Monte Carlo simulations. The root mean square error of the energy estimate between Monte Carlo simulation based results and the parameterization is 3.9%. For the quality factors and RBE estimates it is smaller than 0.9%. The model was successfully integrated into the PSI treatment planning system. It was found that the parameterizations for neutron energy, quality factors and RBE were independent of proton energy in the investigated energy range of interest for proton therapy. The pencil beam algorithm has

  20. Neutrons in proton pencil beam scanning: parameterization of energy, quality factors and RBE.

    PubMed

    Schneider, Uwe; Hälg, Roger A; Baiocco, Giorgio; Lomax, Tony

    2016-08-21

    The biological effectiveness of neutrons produced during proton therapy in inducing cancer is unknown, but potentially large. In particular, since neutron biological effectiveness is energy dependent, it is necessary to estimate, besides the dose, also the energy spectra, in order to obtain quantities which could be a measure of the biological effectiveness and test current models and new approaches against epidemiological studies on cancer induction after proton therapy. For patients treated with proton pencil beam scanning, this work aims to predict the spatially localized neutron energies, the effective quality factor, the weighting factor according to ICRP, and two RBE values, the first obtained from the saturation corrected dose mean lineal energy and the second from DSB cluster induction. A proton pencil beam was Monte Carlo simulated using GEANT. Based on the simulated neutron spectra for three different proton beam energies a parameterization of energy, quality factors and RBE was calculated. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed parameterizations in order to calculate the spatially localized neutron energy, quality factors and RBE for each treated patient. The parameterization represents the simple quantification of neutron energy in two energy bins and the quality factors and RBE with a satisfying precision up to 85 cm away from the proton pencil beam when compared to the results based on 3D Monte Carlo simulations. The root mean square error of the energy estimate between Monte Carlo simulation based results and the parameterization is 3.9%. For the quality factors and RBE estimates it is smaller than 0.9%. The model was successfully integrated into the PSI treatment planning system. It was found that the parameterizations for neutron energy, quality factors and RBE were independent of proton energy in the investigated energy range of interest for proton therapy. The pencil beam algorithm has

  1. Charge neutralized low energy beam transport at Brookhaven 200 MeV linac

    NASA Astrophysics Data System (ADS)

    Raparia, D.; Alessi, J.; Atoian, G.; Zelenski, A.

    2016-02-01

    The H- magnetron source provides about 100 mA H- beam to be match into the radio-frequency quadrupole accelerator. As H- beam traverses through low energy transport, it ionizes the residual gas and electrons are repelled and positive ions are trapped in the beam, due to negative potential of the beam, providing charge neutralization for the H- beam. The neutralization time for the critical density depends upon the background gas and its pressure. Critical density for xenon gas at 35 keV is about 43 times smaller than that of hydrogen and stripping cross section is only 5 times than that of hydrogen gas. We are using xenon gas to reduce neutralization time and to improve transmission through the 200 MeV linac. We are also using pulse nitrogen gas to improve transmission and stability of polarized H- beam from optically pumped polarized ion source.

  2. Charge neutralized low energy beam transport at Brookhaven 200 MeV linac.

    PubMed

    Raparia, D; Alessi, J; Atoian, G; Zelenski, A

    2016-02-01

    The H(-) magnetron source provides about 100 mA H(-) beam to be match into the radio-frequency quadrupole accelerator. As H(-) beam traverses through low energy transport, it ionizes the residual gas and electrons are repelled and positive ions are trapped in the beam, due to negative potential of the beam, providing charge neutralization for the H(-) beam. The neutralization time for the critical density depends upon the background gas and its pressure. Critical density for xenon gas at 35 keV is about 43 times smaller than that of hydrogen and stripping cross section is only 5 times than that of hydrogen gas. We are using xenon gas to reduce neutralization time and to improve transmission through the 200 MeV linac. We are also using pulse nitrogen gas to improve transmission and stability of polarized H(-) beam from optically pumped polarized ion source. PMID:26932107

  3. ABSOLUTE MEASUREMENT OF THE POLARIZATION OF HIGH ENERGY PROTON BEAMS AT RHIC

    SciTech Connect

    MAKDISI,Y.; BRAVAR, A. BUNCE, G. GILL, R.; HUANG, H.; ET AL.

    2007-06-25

    The spin physics program at the Relativistic Heavy Ion Collider (RHIC) requires knowledge of the beam polarization to better than 5%. Such a goal is made the more difficult by the lack of knowledge of the analyzing power of high energy nuclear physics processes. To overcome this, a polarized hydrogen jet target was constructed and installed at one intersection region in RHIC where it intersects both beams and utilizes the precise knowledge of the jet atomic hydrogen beam polarization to measure the analyzing power in proton-proton elastic scattering in the Nuclear Coulomb Interference (CNI) region at the prescribed RHIC proton beam energy. The reverse reaction is used to assess the absolute beam polarization. Simultaneous measurements taken with fast high statistics polarimeters that measure the p-Carbon elastic scattering process also in the CNI region use the jet results to calibrate the latter.

  4. Sub-microsecond beam notching at low energy

    SciTech Connect

    Moehs, D.P.; /Fermilab

    2005-09-01

    A technique for creating a burst of 100 ns notches (beam extinctions) in an H{sup -} beam at 454 kHz has been developed at {le} 20 keV utilizing a Magnetron ion source with a slit extraction system and a split extractor. Each half of the extractor is treated as part of a 50 ohm transmission line which can be pulsed at {+-} 700 volts creating a 1400 volt gradient across the extractor. A beam current reduction of better than 95% has been observed at the end of the Fermilab 400 MeV Linac. Notched multi-turn charge-exchange injection into the Booster, a 400 MeV to 8 GeV synchrotron, has been demonstrated with a charge reduction in the resulting beam gap of 83%. Presently, the trailing edge of the notch may be adversely affected by space charge resulting in a beam recovery with two different time constants. Efforts to minimize this effect are discussed.

  5. Spatial distributions of the energy and energy flux density of partially coherent electromagnetic beams in atmospheric turbulence.

    PubMed

    Li, Jianlong; Lü, Baida; Zhu, Shifu

    2009-07-01

    The formulas of the energy and energy flux density of partially coherent electromagnetic beams in atmospheric turbulence are derived by using Maxwell's equations. Expressions expressed by elements of electric cross spectral density matrixes of the magnetic and the mutual cross spectral density matrix are obtained for the partially coherent electromagnetic beams. Taken the partially coherent Cosh-Gaussian (ChG) electromagnetic beam as a typical example, the spatial distributions of the energy and energy flux density in atmospheric turbulence are numerically calculated. It is found that the turbulence shows a broadening effect on the spatial distributions of the energy and energy flux density. Some interesting results are obtained and explained with regard to their physical nature.

  6. Plasma shaping in laser-plasma accelerators: injection, energy boost and beam collimation

    NASA Astrophysics Data System (ADS)

    Thaury, Cedric

    2015-11-01

    The longitudinal density profile is a key parameter to optimize the properties of electron beams in laser-plasma accelerators. Tailored density profile can notably be used to control injection or increase the electron energy via density tapering. Here we present three different experiments illustrating the use of density tailoring for injecting, increasing the energy or focusing relativistic electron beams. First, we discuss results on shock-front injection in a gas mixture. We show that shocks allow to confine injection and hence to reduce significantly the beam energy spread, compared to pure ionization injection. Then we demonstrate that, with a different setup, shock fronts can also be used to rephase the electron beam with the wakefield. Using this setup we obtained an increase of the electron energy by almost 50 percent. Finally, we present the principle of the laser-plasma lens and show that this device can be used to reduce the electron beam divergence by a factor of almost 3. This last result is of particular importance for applications requiring beam transport; the divergence reduction should actually be sufficient to avoid transverse emittance growth in quadrupole triplets, provided that the energy spread is lower than 3 percent (chromatic emittance growth is due to the combination of large divergence and energy spread).

  7. Energy deposition of heavy ions in the regime of strong beam-plasma correlations.

    PubMed

    Gericke, D O; Schlanges, M

    2003-03-01

    The energy loss of highly charged ions in dense plasmas is investigated. The applied model includes strong beam-plasma correlation via a quantum T-matrix treatment of the cross sections. Dynamic screening effects are modeled by using a Debye-like potential with a velocity dependent screening length that guarantees the known low and high beam velocity limits. It is shown that this phenomenological model is in good agreement with simulation data up to very high beam-plasma coupling. An analysis of the stopping process shows considerably longer ranges and a less localized energy deposition if strong coupling is treated properly.

  8. Studies on Nuclear Astrophysics and Exotic Structure at the Low-Energy RI Beam Facility CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hayakawa, S.; Sakaguchi, Y.; Nakao, T.; Wakabayashi, Y.; Hashimoto, T.; Teranishi, T.; Kubono, S.; Cherubini, S.; Mazzocco, M.; Signorini, C.; Gulino, M.; Di Pietro, A.; Figuera, P.; La Cognata, M.; Lattuada, M.; Spitaleri, C.; Torresi, D.; Lee, P. S.; Lee, C. S.; Komatsubara, T.; Iwasa, N.; Okoda, Y.; Pierroutsakou, D.; Parascandolo, C.; La Commara, M.; Strano, E.; Boiano, C.; Boiano, A.; Manea, C.; Sánchez-Benítez, A. M.; Miyatake, H.; Watanabe, Y. X.; Ishiyama, H.; Jeong, S. C.; Imai, N.; Hirayama, Y.; Kimura, S.; Mukai, M.; Kim, Y. H.; Lin, C. J.; Jia, H. M.; Yan, L.; Yang, Y. Y.; Kawabata, T.; Kwon, Y. K.; Binh, D. N.; Khiem, L. H.; Duy, N. N.

    Studies on nuclear astrophysics, resonant structure, and nuclear reaction are going on at CRIB (CNS Radioactive Ion Beam separator), a low-energy RI beam separator operated by Center for Nuclear Study (CNS), the University of Tokyo. Two major methods used at CRIB to study nuclear reactions of astrophysical relevance are the resonant scattering, and direct measurements of (α,p) reactions using a thick-gas target. Several experiments for decay measurements and reaction mechanism are also performed using low-energy RI beams at CRIB. Some of the results from recent experiments at CRIB are discussed.

  9. Energy deposition of heavy ions in the regime of strong beam-plasma correlations.

    PubMed

    Gericke, D O; Schlanges, M

    2003-03-01

    The energy loss of highly charged ions in dense plasmas is investigated. The applied model includes strong beam-plasma correlation via a quantum T-matrix treatment of the cross sections. Dynamic screening effects are modeled by using a Debye-like potential with a velocity dependent screening length that guarantees the known low and high beam velocity limits. It is shown that this phenomenological model is in good agreement with simulation data up to very high beam-plasma coupling. An analysis of the stopping process shows considerably longer ranges and a less localized energy deposition if strong coupling is treated properly. PMID:12689203

  10. Scintillating screens sensitivity and resolution studies for low energy, low intensity beam diagnostics.

    PubMed

    Harasimowicz, Janusz; Cosentino, Luigi; Finocchiaro, Paolo; Pappalardo, Alfio; Welsch, Carsten P

    2010-10-01

    In order to investigate the limits of scintillating screens for beam profile monitoring in the ultra-low energy, ultra-low intensity regime, CsI:Tl, YAG:Ce, and a Tb glass-based scintillating fiber optic plate (SFOP) were tested. The screens response to 200 and 50 keV proton beams with intensities ranging from a few picoampere down to the subfemtoampere region was examined. In the following paper, the sensitivity and resolution studies are presented in detail for CsI:Tl and the SFOP, the two most sensitive screens. In addition, a possible use of scintillators for ultra-low energy antiproton beam monitoring is discussed.

  11. A review on photoneutrons characteristics in radiation therapy with high-energy photon beams

    PubMed Central

    Naseri, Alireza; Mesbahi, Asghar

    2010-01-01

    In radiation therapy with high-energy photon beams (E > 10 MeV) neutrons are generated mainly in linacs head thorough (γ,n) interactions of photons with nuclei of high atomic number materials that constitute the linac head and the beam collimation system. These neutrons affect the shielding requirements in radiation therapy rooms and also increase the out-of-field radiation dose of patients undergoing radiation therapy with high-energy photon beams. In the current review, the authors describe the factors influencing the neutron production for different medical linacs based on the performed measurements and Monte Carlo studies in the literature. PMID:24376940

  12. Experimental analysis of energy harvesting from self-induced flutter of a composite beam

    SciTech Connect

    Zakaria, Mohamed Y. Al-Haik, Mohammad Y.; Hajj, Muhammad R.

    2015-07-13

    Previous attempts to harvest energy from aeroelastic vibrations have been based on attaching a beam to a moving wing or structure. Here, we exploit self-excited oscillations of a fluttering composite beam to harvest energy using piezoelectric transduction. Details of the beam properties and experimental setup are presented. The effects of preset angle of attack, wind speed, and load resistance on the levels of harvested power are determined. The results point to a complex relation between the aerodynamic loading and its impact on the static deflection and amplitudes of the limit cycle oscillations on one hand and the load resistance and level of power harvested on the other hand.

  13. A particle-in-cell mode beam dynamics simulation of medium energy beam transport for the SSC-Linac

    NASA Astrophysics Data System (ADS)

    Xiao, Chen; He, Yuan; Yuan, You-Jin; Lu, Yuan-Rong; Liu, Yong; Wang, Zhi-Jun; Du, Xiao-Nan; Yao, Qing-Gao; Liu, Ge; Xu, Meng-Xin; He, Shou-Bo; Xia, Jia-Wen

    2012-01-01

    A new linear accelerator system, called the SSC-Linac injector, is being designed at HIRFL (the heavy ion research facility of Lanzhou). As part of the SSC-Linac, the medium energy beam transport (MEBT) consists of seven magnetic quadrupoles, a re-buncher and a diagnose box. The total length of this segment is about 1.75 m. The beam dynamics simulation in MEBT has been studied using the TRACK 3D particle-in-cell code, and the simulation result shows that the beam accelerated from the radio frequency quadrupole (RFQ) matches well with the acceptance of the following drift tube linac (DTL) in both the transverse and longitudinal phase spaces, and that most of the particles can be captured by the final sector focusing cyclotron for further acceleration. The longitudinal emittance of the RFQ and the longitudinal acceptance of the DTL was calculated in detail, and a multi-particle beam dynamics simulation from the ion source to the end of the DTL was done to verify the original design.

  14. High and low energy gamma beam dump designs for the gamma beam delivery system at ELI-NP

    NASA Astrophysics Data System (ADS)

    Yasin, Zafar; Matei, Catalin; Ur, Calin A.; Mitu, Iani-Octavian; Udup, Emil; Petcu, Cristian

    2016-03-01

    The Extreme Light Infrastructure - Nuclear Physics (ELI-NP) is under construction in Magurele, Bucharest, Romania. The facility will use two 10 PW lasers and a high intensity, narrow bandwidth gamma beam for stand-alone and combined laser-gamma experiments. The accurate estimation of particle doses and their restriction within the limits for both personel and general public is very important in the design phase of any nuclear facility. In the present work, Monte Carlo simulations are performed using FLUKA and MCNPX to design 19.4 and 4 MeV gamma beam dumps along with shielding of experimental areas. Dose rate contour plots from both FLUKA and MCNPX along with numerical values of doses in experimental area E8 of the facility are performed. The calculated doses are within the permissible limits. Furthermore, a reasonable agreement between both codes enhances our confidence in using one or both of them for future calculations in beam dump designs, radiation shielding, radioactive inventory, and other calculations releated to radiation protection. Residual dose rates and residual activity calculations are also performed for high-energy beam dump and their effect is negligible in comparison to contributions from prompt radiation.

  15. Tumor therapy with high-energy carbon ion beams

    NASA Astrophysics Data System (ADS)

    Schardt, D.; Heavy-Ion Therapy Collaboration

    2007-05-01

    Heavy-ion beams offer favourable conditions for the treatment of deep-seated local tumors. The well defined range and the small lateral beam spread make it possible to deliver the dose with millimeter precision by applying advanced beam scanning techniques. In addition, heavy ions have an enhanced biological effectiveness in the Bragg peak region which is caused by the dense ionization and the resulting reduced cellular repair rate. Furthermore, heavy ions offer the unique possibility of in-vivo range monitoring by applying Positron-Emission-Tomography (PET) techniques. Taking advantage of these clinically relevant properties, more than 300 patients have been treated with carbon ions at GSI Darmstadt since December 1997 with very promising results. A dedicated heavy-ion treatment center at the Radiological Clinic Heidelberg with a design capacity of 1000 patients per year is under construction and expected to start operation end of 2007.

  16. Efficient Optical Energy Harvesting in Self-Accelerating Beams

    PubMed Central

    Bongiovanni, Domenico; Hu, Yi; Wetzel, Benjamin; Robles, Raul A.; Mendoza González, Gregorio; Marti-Panameño, Erwin A.; Chen, Zhigang; Morandotti, Roberto

    2015-01-01

    We report the experimental observation of energetically confined self-accelerating optical beams propagating along various convex trajectories. We show that, under an appropriate transverse compression of their spatial spectra, these self-accelerating beams can exhibit a dramatic enhancement of their peak intensity and a significant decrease of their transverse expansion, yet retaining both the expected acceleration profile and the intrinsic self-healing properties. We found our experimental results to be in excellent agreement with the numerical simulations. We expect further applications in such contexts where power budget and optimal spatial confinement can be important limiting factors. PMID:26299360

  17. Magnetoelastic beam with extended polymer for low frequency vibration energy harvesting

    NASA Astrophysics Data System (ADS)

    Ibrahim, Alwathiqbellah; Towfighian, Shahrzad; Younis, Mohammad; Su, Quang

    2016-04-01

    Ambient energy in the form of mechanical kinetic energy is mostly considered waste energy. The process of scavenging and storing such energy is known as energy harvesting. Energy harvesting from mechanical vibration is performed using resonant energy harvesters (EH) with two major goals: enhancing the power scavenged at low frequency sources of vibrations, and increasing the efficiency of scavenging energy by increasing the bandwidth near the resonant frequency. Toward such goals, we propose a piezoelectric EH of a composite cantilever beam with a tip magnet facing another magnet at a distance. The composite cantilever consists of a piezoelectric bimorph with an extended polymer material. With the effect of the nonlinearity of the magnetic force, higher amplitude can be achieved because of the generated bi-stability oscillations of the cantilever beam under harmonic excitation. The contribution of the this paper is to demonstrate lowering the achieved resonant frequency down to 17 Hz compared to 100 Hz for the piezoelectric bimorph beam without the extended polymer. Depending on the magnetic distance, the beam responses are divided to mono and bi-stable regions, for which we investigate static and dynamic behaviors. The dynamics of the system and the frequency and voltage responses of the beam are obtained using the shooting method.

  18. Electron beam energy and Ge nanocrystal size effects on the minority carrier diffusion length measured by the nano-electron beam induced current technique

    NASA Astrophysics Data System (ADS)

    Doan, Quang-Tri; El Hdiy, Abdelillah; Troyon, Michel

    2011-07-01

    The near-field electron beam induced current technique is used to study the minority carrier effective diffusion length versus electron beam energy on structures containing spherical Ge nanocrystals (NCs) with diameters of 50 nm and 70 nm formed by a two step dewetting/nucleation process. For both nanocrystal sizes, the effective diffusion length increases with the electron beam energy and then decreases from a threshold energy, which depends on the nanocrystal size. The effective diffusion length is smaller at low energy for NCs of larger size because of their larger surface recombination velocity, due to a better charge trapping efficiency.

  19. A comparative study on low-energy ion beam and neutralized beam modifications of naked DNA and biological effect on mutation

    NASA Astrophysics Data System (ADS)

    Sarapirom, S.; Thongkumkoon, P.; Prakrajang, K.; Anuntalabhochai, S.; Yu, L. D.

    2012-02-01

    DNA conformation change or damage induced by low-energy ion irradiation has been of great interest owing to research developments in ion beam biotechnology and ion beam application in biomedicine. Mechanisms involved in the induction of DNA damage may account for effect from implanting ion charge. In order to check this effect, we used both ion beam and neutralized beam at keV energy to bombard naked DNA. Argon or nitrogen ion beam was generated and extracted from a radiofrequency (RF) ion source and neutralized by microwave-driven plasma in the beam path. Plasmid DNA pGFP samples were irradiated with the ion or neutralized beam in vacuum, followed by gel electrophoresis to observe changes in the DNA conformations. It was revealed that the ion charge played a certain role in inducing DNA conformation change. The subsequent DNA transfer into bacteria Escherichia coli ( E. coli) for mutation analysis indicated that the charged ion beam induced DNA change had high potential in mutation induction while neutralized beam did not. The intrinsic reason was attributed to additional DNA deformation and contortion caused by ion charge exchange effect so that the ion beam induced DNA damage could hardly be completely repaired, whereas the neutralized beam induced DNA change could be more easily recoverable owing to absence of the additional DNA deformation and contortion.

  20. Sensitivity of inelastic response to numerical integration of strain energy. [for cantilever beam

    NASA Technical Reports Server (NTRS)

    Kamat, M. P.

    1976-01-01

    The exact solution to the quasi-static, inelastic response of a cantilever beam of rectangular cross section subjected to a bending moment at the tip is obtained. The material of the beam is assumed to be linearly elastic-linearly strain-hardening. This solution is then compared with three different numerical solutions of the same problem obtained by minimizing the total potential energy using Gaussian quadratures of two different orders and a Newton-Cotes scheme for integrating the strain energy of deformation. Significant differences between the exact dissipative strain energy and its numerical counterpart are emphasized. The consequence of this on the nonlinear transient responses of a beam with solid cross section and that of a thin-walled beam on elastic supports under impulsive loads are examined.

  1. Numerical simulation of material and energy flow in an e-beam melt furnace

    SciTech Connect

    Westerberg, K.W.; McClelland, M.A.; Finlayson, B.A.

    1993-12-01

    A numerical analysis is made of the material and energy flow in an electron-beam furnace. Energy from an electron beam vaporizes metal confined in a water-cooled crucible. At the beam impact site a. recirculating liquid metal pool is surrounded by a shell of its own solid. A Galerkin finite element method is modified to solve for the flow and temperature fields along with interface locations. The deforming mesh is parameterized using spines that pivot and stretch as the interfaces move. Results are given for an aluminum vaporizer in which parametric variations are made in the e-beam power and liquid viscosity. The calculations reveal the importance of the coupling between the free boundaries and the flow and energy fields.

  2. Status of the PXIE Low Energy Beam Transport Line

    SciTech Connect

    Prost, Lionel; Andrews, Richard; Chen, Alex; Hanna, Bruce; Scarpine, Victor; Shemyakin, Alexander; Steimel, Jim; D'Arcy, Richard

    2014-07-01

    A CW-compatible, pulsed H- superconducting RF linac (a.k.a. PIP-II) is envisaged as a possible path for upgrading Fermilab’s injection complex [1]. To validate the concept of the front-end of such machine, a test accelerator (a.k.a. PXIE) [2] is under construction. The warm part of this accelerator comprises a 10 mA DC, 30 keV H- ion source, a 2m-long LEBT, a 2.1 MeV CW RFQ, and a MEBT that feeds the first cryomodule. In addition to operating in the nominal CW mode, the LEBT should be able to produce a pulsed beam for both PXIE commissioning and modelling of the front-end nominal operation in the pulsed mode. Concurrently, it needs to provide effective means of inhibiting beam as part of the overall machine protection system. A peculiar feature of the present LEBT design is the capability of using the ~1m-long section immediately preceding the RFQ in two regimes of beam transport dynamics: neutralized and space charge dominated. This paper introduces the PXIE LEBT, reports on the status of the ion source and LEBT installation, and presents the first beam measurements.

  3. Beam-Flattener Design for High Energy Radiographic Inspection

    NASA Technical Reports Server (NTRS)

    Grandin, Robert; Rudolphi, Thomas

    2009-01-01

    This report documents the work done to develop a beam flattener for use in the inspection of rocket motors at ATK Space Systems Utah facilities. The following pages provide a brief introduction to the necessity of this project, comprehensive description of the design methodology, and experimentally-based conclusions regarding project success.

  4. Beam-dynamics driven design of the LHeC energy-recovery linac

    NASA Astrophysics Data System (ADS)

    Pellegrini, Dario; Latina, Andrea; Schulte, Daniel; Bogacz, S. Alex

    2015-12-01

    The LHeC is envisioned as a natural upgrade of the LHC that aims at delivering an electron beam for collisions with the existing hadronic beams. The current baseline design for the electron facility consists of a multipass superconducting energy-recovery linac (ERL) operating in a continuous wave mode. The unprecedently high energy of the multipass ERL combined with a stringent emittance dilution budget poses new challenges for the beam optics. Here, we investigate the performances of a novel arc architecture based on a flexible momentum compaction lattice that mitigates the effects of synchrotron radiation while containing the bunch lengthening. Extensive beam-dynamics investigations have been performed with placet2, a recently developed tracking code for recirculating machines. They include the first end-to-end tracking and a simulation of the machine operation with a continuous beam. This paper briefly describes the Conceptual Design Report lattice, with an emphasis on possible and proposed improvements that emerged from the beam-dynamics studies. The detector bypass section has been integrated in the lattice, and its design choices are presented here. The stable operation of the ERL with a current up to ˜150 mA in the linacs has been validated in the presence of single- and multibunch wakefields, synchrotron radiation, and beam-beam effects.

  5. Method and apparatus for measuring the momentum, energy, power, and power density profile of intense particle beams

    DOEpatents

    Gammel, George M.; Kugel, Henry W.

    1992-10-06

    A method and apparatus for determining the power, momentum, energy, and power density profile of high momentum mass flow. Small probe projectiles of appropriate size, shape and composition are propelled through an intense particle beam at equal intervals along an axis perpendicular to the beam direction. Probe projectiles are deflected by collisions with beam particles. The net beam-induced deflection of each projectile is measured after it passes through the intense particle beam into an array of suitable detectors.

  6. Absolute energy calibration for relativistic electron beams with pointing instability from a laser-plasma accelerator

    SciTech Connect

    Cha, H. J.; Choi, I. W.; Kim, H. T.; Kim, I J.; Nam, K. H.; Jeong, T. M.; Lee, J.

    2012-06-15

    The pointing instability of energetic electron beams generated from a laser-driven accelerator can cause a serious error in measuring the electron spectrum with a magnetic spectrometer. In order to determine a correct electron spectrum, the pointing angle of an electron beam incident on the spectrometer should be exactly defined. Here, we present a method for absolutely calibrating the electron spectrum by monitoring the pointing angle using a scintillating screen installed in front of a permanent dipole magnet. The ambiguous electron energy due to the pointing instability is corrected by the numerical and analytical calculations based on the relativistic equation of electron motion. It is also possible to estimate the energy spread of the electron beam and determine the energy resolution of the spectrometer using the beam divergence angle that is simultaneously measured on the screen. The calibration method with direct measurement of the spatial profile of an incident electron beam has a simple experimental layout and presents the full range of spatial and spectral information of the electron beams with energies of multi-hundred MeV level, despite the limited energy resolution of the simple electron spectrometer.

  7. Determination of Endpoint Energy and Bremsstrahlung Spectra for High-Energy Radiation-Therapy Beams

    NASA Astrophysics Data System (ADS)

    Landry, Danny Joe

    Few attempts have been made to experimentally determine thick-target bremsstrahlung spectra of megavoltage therapy beams. For spectral studies using the Compton scattering technique, sodium iodine (NaI) detectors with relatively poor energy resolution have been used. Other experimental techniques for determining spectra are generally not suited for a clinical environment with the inherent time and space constraints. To gather more spectral information than previously obtained in the region near the endpoint energy, the use of a high-resolution intrinsic-germanium (Ge) detector was proposed. A response function matrix was determined from experimentally obtained pulse height distributions on the multichannel analyzer. The distributions were for nine various monoenergetic sources between 280 adn 1525 keV. The response function was used to convert the measured pulse height distributions to photon flux spectra using an iterative approximation technique with a computer. Photon flux spectra from the Sagittaire Linear Accelerator were obtained at average-electron endpoint energies of 15, 20, and 25 MeV. Two spectra were measured at the 25 MeV setting; one spectrum was measured along the central axis and one spectrum at 4(DEGREES) off axis. Photon spectra were also obtained for a Van de Graaff generator at the nominal endpoint energies of 2.2, 2.35, and 2.5 MeV. The results for both the linac and the Van de Graaff generator were compared with theoretical spectra and previously measured spectra where available. Also, photon spectra from a Theratron-80 (('60)Co) unit were determined for three field sizes and for a 10 x 10 cm. field with a lucite tray or a 45(DEGREES) wedge in the beam. The resulting spectra were compared to previously measured ('60)Co spectra.

  8. A performance-enhanced energy harvester for low frequency vibration utilizing a corrugated cantilevered beam

    NASA Astrophysics Data System (ADS)

    Kim, In-Ho; Jin, SeungSeop; Jang, Seon-Jun; Jung, Hyung-Jo

    2014-03-01

    This note proposes a performance-enhanced piezoelectric energy harvester by replacing a conventional flat cantilevered beam with a corrugated beam. It consists of a proof mass and a sinusoidally or trapezoidally corrugated cantilevered beam covered by a polyvinylidene fluoride (PVDF) film. Compared to the conventional energy harvester of the same size, it has a more flexible bending stiffness and a larger bonding area of the PVDF layer, so higher output voltage from the device can be expected. In order to investigate the characteristics of the proposed energy harvester, analytical developments and numerical simulations on its natural frequency and tip displacement are carried out. Shaking table tests are also conducted to verify the performance of the proposed device. It is clearly shown from the tests that the proposed energy harvester not only has a lower natural frequency than an equivalent sized standard energy harvester, but also generates much higher output voltage than the standard one.

  9. Energy Loss of High Intensity Focused Proton Beams Penetrating Metal Foils

    NASA Astrophysics Data System (ADS)

    McGuffey, C.; Qiao, B.; Kim, J.; Beg, F. N.; Wei, M. S.; Evans, M.; Fitzsimmons, P.; Stephens, R. B.; Chen, S. N.; Fuchs, J.; Nilson, P. M.; Canning, D.; Mastrosimone, D.; Foord, M. E.

    2014-10-01

    Shortpulse-laser-driven intense ion beams are appealing for applications in probing and creating high energy density plasmas. Such a beam isochorically heats and rapidly ionizes any target it enters into warm dense matter with uncertain transport and stopping properties. Here we present experimental measurements taken with the 1.25 kJ, 10 ps OMEGA EP BL shortpulse laser of the proton and carbon spectra after passing through metal foils. The laser irradiated spherically curved C targets with intensity 4×1018 W/cm2, producing proton beams with 3 MeV slope temperature and a sharp low energy cutoff at 5 MeV which has not been observed on lower energy, shorter pulse intense lasers. The beam either diverged freely or was focused to estimated 1016 p +/cm2 ps by a surrounding structure before entering the metal foils (Al or Ag and a Cu tracer layer). The proton and ion spectra were altered by the foil depending on material and whether or not the beam was focused. Transverse proton radiography probed the target with ps temporal and 10 micron spatial resolution, indicating an electrostatic field on the foil may also have affected the beam. We present complementary particle-in-cell simulations of the beam generation and transport to the foils. This work was supported by the DOE/NNSA National Laser User Facility program, Contract DE-SC0001265.

  10. Isotope-Shift Measurement of High-energy Highly Charged Ion Beams

    NASA Astrophysics Data System (ADS)

    Ozawa, S.; Ariga, T.; Inabe, N.; Kase, M.; Tanihata, I.; Wakasugi, M.; Yano, Y.

    2001-10-01

    Isotope-shift measurement by the laser spectroscopic method was aimed to apply for radioactive isotope beams up to uranium created by projectile fragmentation at RIKEN RI beam factory (T. Katayama, et al.,): Nucl. Phys., A626, 545c (1997).to make a systematic study of the mean square nuclear charge radii. The present work was started to verify the feasibility of the method. Projectile fragments are high-energy highly charged ions and weak currents. Therefore we designed ultralow-background photon-detection system (M. Wakasugi, et al.,): Nucl. Instr. and Meth., A419, 50 (1998).for collinear laser spectroscopy of such ion beams. To demonstrate isotope-shift measurement, we measured precisely the 1s2s ^3S_1-1s2p ^3P_0,1,2 transition energy of He-like ^12C ion accelerated up to 0.9 MeV/u and ^13C ion 0.6 MeV/u. For the precision measurement, the uncertainty coming from the ambiguity in the absolute ion beam velocity was suppressed by means of that the resonance energy was measured by two laser beams which propagate in parallel and anti-parallel directions to the ion beam. As the result, isotope shifts of these transitions were obtained with the accuracy of 10 %. The lower limit of the ion-beam intensity for the measurement is estimated to be 2000 ions/s.

  11. SU-E-T-359: Measurement of Various Metrics to Determine Changes in Megavoltage Photon Beam Energy

    SciTech Connect

    Gao, S; Balter, P; Rose, M; Simon, W

    2014-06-01

    Purpose: To examine the relationship between photon beam energy and various metrics for energy on the flattened and flattening filter free (FFF) beams generated by the Varian TrueBeam. Methods: Energy changes were accomplished by adjusting the bending magnet current ±10% from the nominal value for the 4, 6, 8, and 10 MV flattened and 6 and 10 MV FFF beams. Profiles were measured for a 30×30 cm{sup 2} field using a 2D ionization chamber array and a 3D water Scanner which was also used to measure PDDs. For flattened beams we compared several energy metrics; PDD at 10 cm depth in water (PDD(10)); the variation over the central 80% of the field (Flat); and the average of the highest reading along each diagonal divided by the CAX value, diagonal normalized flatness (FDN). For FFF beams we examined PDD(10), FDN, and the width of a chosen isodose level in a 30×30 cm{sup 2} field (W(d%)). Results: Changes in PDD(10) were nearly linear with changes in energy for both flattened and FFF beams as were changes in FDN. Changes in W(d%) were also nearly linear with energy for the FFF beams. PDD(10) was not as sensitive to changes in energy compared to the other metrics for either flattened or FFF beams. Flat was not as sensitive to changes in energy compared to FDN for flattened beams and its behavior depends on depth. FDN was the metric that had the highest sensitivity to the changes in energy for flattened beams while W(d%) was the metric that had highest sensitivity to the changes in energy for FFF beams. Conclusions: The metric FDN was found to be most sensitive to energy changes for flattened beams, while the W(d%) was most sensitive to energy changes for FFF beams.

  12. Nonlinear optical beam manipulation and high energy beam propagation through the atmosphere; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

    SciTech Connect

    Fisher, R.A.; Wilson, L.E.

    1989-01-01

    Various papers on nonlinear optical beam manipulation and high-energy beam propagation through the atmosphere are presented. Individual topics addressed include: suppression of Raman amplification using large Stokes seeds, review of multiple-short-pulse SBS experiments and theory, laser-induced gratings for beam manipulation in a gas, considerations for computing realistic atmospheric distortion parameter profiles, effect of turbulent diffusion on laser propagation, use of multiple photon processes in krypton for laser guiding of electron beams, effect of ionization on intense electron beam propagation in low-pressure media, lidar measurements of the troposphere and middle atmosphere, seasonal and diurnal changes in cloud obscuration to visible and IR energy transmission, new cloud composite climatologies using meteorological satellite imagery, effect of neutral atmospheric structure on beam propagation, small-scale electron density fluctuations in a disturbed ionospheric environment, and SDIO radio frequency communications in a structured environment.

  13. One dimensional heavy ion beam transport: Energy independent model. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Farhat, Hamidullah

    1990-01-01

    Attempts are made to model the transport problem for heavy ion beams in various targets, employing the current level of understanding of the physics of high-charge and energy (HZE) particle interaction with matter are made. An energy independent transport model, with the most simplified assumptions and proper parameters is presented. The first and essential assumption in this case (energy independent transport) is the high energy characterization of the incident beam. The energy independent equation is solved and application is made to high energy neon (NE-20) and iron (FE-56) beams in water. The numerical solutions is given and compared to a numerical solution to determine the accuracy of the model. The lower limit energy for neon and iron to be high energy beams is calculated due to Barkas and Burger theory by LBLFRG computer program. The calculated values in the density range of interest (50 g/sq cm) of water are: 833.43 MeV/nuc for neon and 1597.68 MeV/nuc for iron. The analytical solutions of the energy independent transport equation gives the flux of different collision terms. The fluxes of individual collision terms are given and the total fluxes are shown in graphs relative to different thicknesses of water. The values for fluxes are calculated by the ANASTP computer code.

  14. Interactions of vortices with a flexible beam with applications in fluidic energy harvesting

    NASA Astrophysics Data System (ADS)

    Goushcha, O.; Elvin, N.; Andreopoulos, Y.

    2014-01-01

    A cantilever piezoelectric beam immersed in a flow and subjected to naturally occurring vortices such as those formed in the wake of bluff bodies can be used to generate electrical energy harvested in fluid flows. In this paper, we present the pressure distribution and deflection of a piezoelectric beam subjected to controlled vortices. A custom designed experimental facility is set up to study the interaction of individual and multiple vortices with the beam. Vortex tori are generated by an audio speaker and travel at controlled rates over the beam. Particle image velocimetry is used to measure the 2-D flow field induced by each vortex and estimate the effect of pressure force on the beam deflection.

  15. Beam-dynamics driven design of the LHeC energy-recovery linac

    SciTech Connect

    Pellegrini, Dario; Latina, Andrea; Schulte, Daniel; Bogacz, S. Alex

    2015-12-23

    The LHeC study is a possible upgrade of the LHC that aims at delivering an electron beam for collisions with the existing hadronic beams. The current baseline design for the electron facility consists of a multi-pass superconducting energy-recovery linac operating in a continuous wave mode. Here, we summarize the overall layout of such ERL complex located on the LHC site and introduce the most recent developments. We review of the lattice components, presenting their baseline design along with possible alternatives that aims at improving the overall machine performance. The detector bypass has been designed and integrated into the lattice. Tracking simulations allowed us to verify the high current (~150 mA in the linacs) beam operation required for the LHeC to serve as an Higgs Factory. The impact of single and multi-bunch wake-fields, synchrotron radiation and beam-beam effects has been assessed in this paper.

  16. Interactions of vortices with a flexible beam with applications in fluidic energy harvesting

    SciTech Connect

    Goushcha, O.; Elvin, N.; Andreopoulos, Y.

    2014-01-13

    A cantilever piezoelectric beam immersed in a flow and subjected to naturally occurring vortices such as those formed in the wake of bluff bodies can be used to generate electrical energy harvested in fluid flows. In this paper, we present the pressure distribution and deflection of a piezoelectric beam subjected to controlled vortices. A custom designed experimental facility is set up to study the interaction of individual and multiple vortices with the beam. Vortex tori are generated by an audio speaker and travel at controlled rates over the beam. Particle image velocimetry is used to measure the 2-D flow field induced by each vortex and estimate the effect of pressure force on the beam deflection.

  17. Design of low energy beam transport for new LANSCE H+ injector

    NASA Astrophysics Data System (ADS)

    Batygin, Y. K.; Draganic, I. N.; Fortgang, C. M.; Garnett, R. W.; Kurennoy, S. S.; McCrady, R. C.; O'Hara, J. F.; Rybarcyk, L. J.

    2014-07-01

    The present LANSCE injector utilizes two 750-keV Cockcroft-Walton (CW) based injectors for simultaneous injection of H+ and H- beams into 800-MeV accelerator. To reduce long-term operational risks, the new project to replace the existing H+ CW injector with a Radio-Frequency Quadrupole (RFQ) accelerator is underway [1]. The new injector requires a Low-Energy Beam Transport (LEBT). An ion source and 2-solenoid magnetic LEBT have been designed and optimized to transport beams over a wide range of space-charge neutralization and transverse emittance, while allowing sufficient space for diagnostics and a beam deflector. The design layout minimizes the beam size in the LEBT and potential emittance growth due to solenoid aberrations and nonlinear space-charge forces. This paper describes the details of the LEBT design activity.

  18. Dual-source multi-energy CT with triple or quadruple x-ray beams

    NASA Astrophysics Data System (ADS)

    Yu, Lifeng; Li, Zhoubo; Leng, Shuai; McCollough, Cynthia H.

    2016-03-01

    Energy-resolved photon-counting CT (PCCT) is promising for material decomposition with multi-contrast agents. However, corrections for non-idealities of PCCT detectors are required, which are still active research areas. In addition, PCCT is associated with very high cost due to lack of mass production. In this work, we proposed an alternative approach to performing multi-energy CT, which was achieved by acquiring triple or quadruple x-ray beam measurements on a dual-source CT scanner. This strategy was based on a "Twin Beam" design on a single-source scanner for dual-energy CT. Examples of beam filters and spectra for triple and quadruple x-ray beam were provided. Computer simulation studies were performed to evaluate the accuracy of material decomposition for multi-contrast mixtures using both tri-beam and quadruple-beam configurations. The proposed strategy can be readily implemented on a dual-source scanner, which may allow material decomposition of multi-contrast agents to be performed on clinical CT scanners with energy-integrating detector.

  19. Electron-Excited X-Ray Microanalysis at Low Beam Energy: Almost Always an Adventure!

    PubMed

    Newbury, Dale E; Ritchie, Nicholas W M

    2016-08-01

    Scanning electron microscopy with energy-dispersive spectrometry has been applied to the analysis of various materials at low-incident beam energies, E 0≤5 keV, using peak fitting and following the measured standards/matrix corrections protocol embedded in the National Institute of Standards and Technology Desktop Spectrum Analyzer-II analytical software engine. Low beam energy analysis provides improved spatial resolution laterally and in-depth. The lower beam energy restricts the atomic shells that can be ionized, reducing the number of X-ray peak families available to the analyst. At E 0=5 keV, all elements of the periodic table except H and He can be measured. As the beam energy is reduced below 5 keV, elements become inaccessible due to lack of excitation of useful characteristic X-ray peaks. The shallow sampling depth of low beam energy microanalysis makes the technique more sensitive to surface compositional modification due to formation of oxides and other reaction layers. Accurate and precise analysis is possible with the use of appropriate standards and by accumulating high count spectra of unknowns and standards (>1 million counts integrated from 0.1 keV to E 0). PMID:27515566

  20. Electron-Excited X-Ray Microanalysis at Low Beam Energy: Almost Always an Adventure!

    PubMed

    Newbury, Dale E; Ritchie, Nicholas W M

    2016-08-01

    Scanning electron microscopy with energy-dispersive spectrometry has been applied to the analysis of various materials at low-incident beam energies, E 0≤5 keV, using peak fitting and following the measured standards/matrix corrections protocol embedded in the National Institute of Standards and Technology Desktop Spectrum Analyzer-II analytical software engine. Low beam energy analysis provides improved spatial resolution laterally and in-depth. The lower beam energy restricts the atomic shells that can be ionized, reducing the number of X-ray peak families available to the analyst. At E 0=5 keV, all elements of the periodic table except H and He can be measured. As the beam energy is reduced below 5 keV, elements become inaccessible due to lack of excitation of useful characteristic X-ray peaks. The shallow sampling depth of low beam energy microanalysis makes the technique more sensitive to surface compositional modification due to formation of oxides and other reaction layers. Accurate and precise analysis is possible with the use of appropriate standards and by accumulating high count spectra of unknowns and standards (>1 million counts integrated from 0.1 keV to E 0).

  1. A comparison of phantom scatter from flattened and flattening filter free high-energy photon beams

    SciTech Connect

    Richmond, Neil; Allen, Vince; Daniel, Jim; Dacey, Rob; Walker, Chris

    2015-04-01

    Flattening filter free (FFF) photon beams have different dosimetric properties from those of flattened beams. The aim of this work was to characterize the collimator scatter (S{sub c}) and total scatter (S{sub cp}) from 3 FFF beams of differing quality indices and use the resulting mathematical fits to generate phantom scatter (S{sub p}) data. The similarities and differences between S{sub p} of flattened and FFF beams are described. S{sub c} and S{sub cp} data were measured for 3 flattened and 3 FFF high-energy photon beams (Varian 6 and 10 MV and Elekta 6 MV). These data were fitted to logarithmic power law functions with 4 numerical coefficients. The agreement between our experimentally determined flattened beam S{sub p} and published data was within ± 1.2% for all 3 beams investigated and all field sizes from 4 × 4 to 40 × 40 cm{sup 2}. For the FFF beams, S{sub p} was only within 1% of the same flattened beam published data for field sizes between 6 × 6 and 14 × 14 cm{sup 2}. Outside this range, the differences were much greater, reaching − 3.2%, − 4.5%, and − 4.3% for the fields of 40 × 40 cm{sup 2} for the Varian 6-MV, Varian 10-MV, and Elekta 6-MV FFF beams, respectively. The FFF beam S{sub p} increased more slowly with increasing field size than that of the published and measured flattened beam of a similar reference field size quality index, i.e., there is less Phantom Scatter than that found with flattened beams for a given field size. This difference can be explained when the fluence profiles of the flattened and FFF beams are considered. The FFF beam has greatly reduced fluence off axis, especially as field size increases, compared with the flattened beam profile; hence, less scatter is generated in the phantom reaching the central axis.

  2. Beam-Beam Interactions

    SciTech Connect

    Sramek, Christopher

    2003-09-05

    At the interaction point of a particle accelerator, various phenomena occur which are known as beam-beam effects. Incident bunches of electrons (or positrons) experience strong electromagnetic fields from the opposing bunches, which leads to electron deflection, beamstrahlung and the creation of electron/positron pairs and hadrons due to two-photon exchange. In addition, the beams experience a ''pinch effect'' which focuses each beam and results in either a reduction or expansion of their vertical size. Finally, if a beam's disruption parameter is too large, the beam can develop a sinusoidal distortion, or two-stream (kink) instability. This project simulated and studied these effects as they relate to luminosity, deflection angles and energy loss in order to optimize beam parameters for the Next Linear Collider (NLC). Using the simulation program Guinea-Pig, luminosity, deflection angle and beam energy data was acquired for different levels of beam offset and distortion. Standard deflection curves and luminosity plots agreed with theoretical models but also made clear the difficulties of e-e- feedback. Simulations emphasizing kink instability in modulated and straight beam collisions followed qualitative behavioral predictions and roughly fit recent analytic calculations. Finally, a study of e-e- collisions under design constraints for the NLC provided new estimates of how luminosity, beamstrahlung energy loss, upsilon parameter and deflection curve width scale with beam spotsizes.

  3. Energy exchange between a laser beam and charged particles using inverse transition radiation and method for its use

    DOEpatents

    Kimura, Wayne D.; Romea, Richard D.; Steinhauer, Loren C.

    1998-01-01

    A method and apparatus for exchanging energy between relativistic charged particles and laser radiation using inverse diffraction radiation or inverse transition radiation. The beam of laser light is directed onto a particle beam by means of two optical elements which have apertures or foils through which the particle beam passes. The two apertures or foils are spaced by a predetermined distance of separation and the angle of interaction between the laser beam and the particle beam is set at a specific angle. The separation and angle are a function of the wavelength of the laser light and the relativistic energy of the particle beam. In a diffraction embodiment, the interaction between the laser and particle beams is determined by the diffraction effect due to the apertures in the optical elements. In a transition embodiment, the interaction between the laser and particle beams is determined by the transition effect due to pieces of foil placed in the particle beam path.

  4. Mechanical Design of a High Energy Beam Absorber for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab

    SciTech Connect

    Baffes, C.; Church, M.; Leibfritz, J.; Oplt, S.; Rakhno, I.; /Fermilab

    2012-05-10

    A high energy beam absorber has been built for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab. In the facility's initial configuration, an electron beam will be accelerated through 3 TTF-type or ILC-type SRF cryomodules to an energy of 750MeV. The electron beam will be directed to one of multiple downstream experimental and diagnostic beam lines and then deposited in one of two beam absorbers. The facility is designed to accommodate up to 6 cryomodules, which would produce a 75kW beam at 1.5GeV; this is the driving design condition for the beam absorbers. The beam absorbers consist of water-cooled graphite, aluminum and copper layers contained in a helium-filled enclosure. This paper describes the mechanical implementation of the beam absorbers, with a focus on thermal design and analysis. The potential for radiation-induced degradation of the graphite is discussed.

  5. Low-energy neutrinos at off-axis from a standard beta beam

    SciTech Connect

    Lazauskas, R.; Volpe, C.; Balantekin, A. B.; Jesus, J. H. de

    2007-09-01

    We discuss a scenario to extract up to 150 MeV neutrinos at a standard beta-beam facility using one and two detectors off-axis. In particular we show that the high-energy component of the neutrino fluxes can be subtracted through a specific combination of the response of two off-axis detectors. A systematic analysis of the neutrino fluxes using different detector geometries is presented, as well as a comparison with the expected fluxes at a low-energy beta-beam facility. The presented option could offer an alternative way to perform low-energy neutrino experiments.

  6. In-situ determination of energy species yields of intense particle beams

    DOEpatents

    Kugel, H.W.; Kaita, R.

    1983-09-26

    Objects of the present invention are provided for a particle beam having a full energy component at least as great as 25 keV, which is directed onto a beamstop target, such that Rutherford backscattering, preferably near-surface backscattering occurs. The geometry, material composition and impurity concentration of the beam stop are predetermined, using any suitable conventional technique. The energy-yield characteristic response of backscattered particles is measured over a range of angles using a fast ion electrostatic analyzer having a microchannel plate array at its focal plane. The knee of the resulting yield curve, on a plot of yield versus energy, is analyzed to determine the energy species components of various beam particles having the same mass.

  7. Evaluation test of the energy monitoring device in industrial electron beam facilities

    NASA Astrophysics Data System (ADS)

    Fuochi, P. G.; Lavalle, M.; Martelli, A.; Corda, U.; Cornia, G.; Kovács, A.

    2009-07-01

    The electron beam energy monitoring device, previously developed and tested under standard laboratory conditions using electron beams in the energy range 4-12 MeV, has now been tested under industrial irradiation conditions in high-energy, high-power electron beam facilities. The measuring instrument was improved in order to measure high peak current delivered at low pulse repetition rate as well. Tests, with good results, were carried out at two different EB plants: one equipped with a LUE-8 linear electron accelerator of 7 MeV maximum energy used for cross-linking of cables and for medical device sterilization, and the other with a 10 MeV Rhodotron type TT 100 used for in-house sterilization.

  8. Design and Implementation of an Acoustic X-ray Detector to Measure the LCLS Beam Energy

    SciTech Connect

    Loos, Jennifer L.; /San Jose State U. /SLAC

    2010-08-25

    On April 11, 2009, first light was seen from LCLS. The present apparatus being used to measure the x-ray beam energy is the Total Energy Sensor which uses a suite of thermal sensors. Another device is needed to cross-check the energy measurements. This new diagnostic tool utilizes radiation acoustic phenomena to determine the x-ray beam energy. A target is hit by the x-rays from the beam, and a voltage is generated in two piezoelectric sensors attached to the target in response to the consequent deformation. Once the voltage is known, the power can be obtained. Thermal sensors will also be attached to the target for calibration purposes. Material selection and design were based on: durability, ultra-high vacuum compatibility, safety and thermal properties. The target material was also chosen for its acoustic properties which were determined from tests using a frequency generator and laser. Initial tests suggest the device will function as anticipated.

  9. Effect of secondary electrons suppression on emittance measurement of an intense, low-energy beam

    SciTech Connect

    Weissman, L.

    2014-02-15

    Transversal emittance measurements of intense low-energy beams involve use of collimators. As most of the beam is stopped by a collimator, a question arises whether the special conditions in the vicinity of the collimator influence emittance measurement. In particular, the secondary electrons emitted from the slit surface may affect the measurement of the beam phase distribution. We have observed significant modification in the measured phase space distribution of a 5–6 mA DC proton beam at the Soreq Applied Research Accelerator Facility low-energy transport after application of a weak magnetic field in the plane of the slit collimator. The periphery region of the phase distribution was mostly affected. The overall effect on the emittance value was as large as 20%.

  10. The edge transient-current technique (E-TCT) with high energy hadron beam

    NASA Astrophysics Data System (ADS)

    Gorišek, Andrej; Cindro, Vladimir; Kramberger, Gregor; Mandić, Igor; Mikuž, Marko; Muškinja, Miha; Zavrtanik, Marko

    2016-09-01

    We propose a novel way to investigate the properties of silicon and CVD diamond detectors for High Energy Physics experiments complementary to the already well-established E-TCT technique using laser beam. In the proposed setup the beam of high energy hadrons (MIPs) is used instead of laser beam. MIPs incident on the detector in the direction parallel to the readout electrode plane and perpendicular to the edge of the detector. Such experiment could prove very useful to study CVD diamond detectors that are almost inaccessible for the E-TCT measurements with laser due to large band-gap as well as to verify and complement the E-TCT measurements of silicon. The method proposed is being tested at CERN in a beam of 120 GeV hadrons using a reference telescope with track resolution at the DUT of few μm. The preliminary results of the measurements are presented.

  11. Experimental study of ultrasonic beam sectors for energy conversion into Lamb waves and Rayleigh waves.

    PubMed

    Declercq, Nico Felicien

    2014-02-01

    When a bounded beam is incident on an immersed plate Lamb waves or Rayleigh waves can be generated. Because the amplitude of a bounded beam is not constant along its wave front, a specific beam profile is formed that influences the local efficiency of energy conversion of incident sound into Lamb waves or Rayleigh waves. Understanding this phenomenon is important for ultrasonic immersion experiments of objects because the quality of such experiments highly depends on the amount of energy transmitted into the object. This paper shows by means of experiments based on monochromatic Schlieren photography that the area within the bounded beam responsible for Lamb wave generation differs from that responsible for Rayleigh wave generation. Furthermore it provides experimental verification of an earlier numerical study concerning Rayleigh wave generation.

  12. Note: High-efficiency energy harvester using double-clamped piezoelectric beams

    SciTech Connect

    Zheng, Yingmei; Wu, Xuan; Parmar, Mitesh; Lee, Dong-weon

    2014-02-15

    In this study, an improvement in energy conversion efficiency has been reported, which is realized by using a double-clamped piezoelectric beam, based on uniaxial stretching strain. The buckling mechanism is applied to maximize axial stress in the double-clamped beam. The voltage generated by using the double-clamped piezoelectric beam is higher than that generated by using other conventional structures, such as bending cantilevers coated/sandwiched with piezoelectric film, which is proven both theoretically and experimentally. The power generation efficiency is enhanced by further optimizing the double-clamped structure. The optimized high-efficiency energy harvester utilizing double-clamped piezoelectric beams generates a peak output power of 80 μW, under an acceleration of 0.1g.

  13. Note: high-efficiency energy harvester using double-clamped piezoelectric beams.

    PubMed

    Zheng, Yingmei; Wu, Xuan; Parmar, Mitesh; Lee, Dong-weon

    2014-02-01

    In this study, an improvement in energy conversion efficiency has been reported, which is realized by using a double-clamped piezoelectric beam, based on uniaxial stretching strain. The buckling mechanism is applied to maximize axial stress in the double-clamped beam. The voltage generated by using the double-clamped piezoelectric beam is higher than that generated by using other conventional structures, such as bending cantilevers coated/sandwiched with piezoelectric film, which is proven both theoretically and experimentally. The power generation efficiency is enhanced by further optimizing the double-clamped structure. The optimized high-efficiency energy harvester utilizing double-clamped piezoelectric beams generates a peak output power of 80 μW, under an acceleration of 0.1g. PMID:24593401

  14. Note: high-efficiency energy harvester using double-clamped piezoelectric beams.

    PubMed

    Zheng, Yingmei; Wu, Xuan; Parmar, Mitesh; Lee, Dong-weon

    2014-02-01

    In this study, an improvement in energy conversion efficiency has been reported, which is realized by using a double-clamped piezoelectric beam, based on uniaxial stretching strain. The buckling mechanism is applied to maximize axial stress in the double-clamped beam. The voltage generated by using the double-clamped piezoelectric beam is higher than that generated by using other conventional structures, such as bending cantilevers coated/sandwiched with piezoelectric film, which is proven both theoretically and experimentally. The power generation efficiency is enhanced by further optimizing the double-clamped structure. The optimized high-efficiency energy harvester utilizing double-clamped piezoelectric beams generates a peak output power of 80 μW, under an acceleration of 0.1g.

  15. Simulations of the High-Energy Beam-Transport (HEBT) section at FRANZ

    NASA Astrophysics Data System (ADS)

    Hinrichs, O.; Arda, C.; Claessens, C.; Fiebiger, S.; Meusel, O.; Noll, D.; Reich, M.; Reifarth, R.; Schmidt, S.; Schwarz, M.; Sonnabend, K.; Thomas, B.

    2016-11-01

    The neutron source FRANZ (Frankfurter Neutronenquelle am Stern-Gerlach-Zentrum), which is currently under construction, will be the neutron source with the highest intensity in the nuclear-astrophysically relevant energy region. The TraceWin code was used to design the High-Energy Beam-Transport section with regard to the experimental requirements at different target positions.

  16. Low-energy neutrino-nucleus interactions and beta-beam neutrino

    SciTech Connect

    Jachowicz, N.; Pandey, V.

    2015-05-15

    We present an overview of neutrino-nucleus scattering at low energies with cross sections obtained within a continuum random phase approximation (CRPA) formalism. We highlight potential applications of beta-beam neutrino experiments for neutrino astrophysics. Our calculations are compared with MiniBooNe data at intermediate energies.

  17. Design of a compact Faraday cup for low energy, low intensity ion beams

    NASA Astrophysics Data System (ADS)

    Cantero, E. D.; Sosa, A.; Andreazza, W.; Bravin, E.; Lanaia, D.; Voulot, D.; Welsch, C. P.

    2016-01-01

    Beam intensity is one of the key parameters in particle accelerators, in particular during machine commissioning, but also during operation for experiments. At low beam energies and low intensities a number of challenges arise in its measurement as commonly used non-invasive devices are no longer sensitive enough. It then becomes necessary to stop the beam in order to measure its absolute intensity. A very compact Faraday cup for determining ion beam currents from a few nanoamperes down to picoamperes for the HIE-ISOLDE post-accelerator at CERN has been designed, built and tested with beam. It has a large aperture diameter of 30 mm and a total length of only 16 mm, making it one of the most compact designs ever used. In this paper we present the different steps that were involved in the design and optimization of this device, including beam tests with two early prototypes and the final monitor. We also present an analysis of the losses caused by secondary particle emission for different repelling electrode voltages and beam energies. Finally, we show that results obtained from an analytical model for electron loss probability combined with Monte Carlo simulations of particles trajectories provide a very good agreement with experimental data.

  18. Polarization beam combination technique for gain saturation effect compensation in high-energy systems

    NASA Astrophysics Data System (ADS)

    Chen, Junchi; Peng, Yujie; Su, Hongpeng; Leng, Yuxin

    2016-06-01

    To compensate for the gain saturation effect in the high-energy laser amplifier, a modified polarization beam combination (PBC) method is introduced to reshape temporal waveform of the injected laser pulse to obtain a controlled high-energy laser pulse shape after amplification. One linearly polarized beam is divided into two orthogonal polarized beams, which spatially recombine together collinearly after propagating different optical paths with relative time delay in PBC structure. The obtained beam with polarization direction being rotated by the following half wave plate is divided and combined again to reform a new beam in another modified polarization beam structure. The reformed beam is injected into three cascaded laser amplifiers. The amplified pulse shape can be controlled by the incident pulse shape and amplifier gain, which is agreeable to the simulation by the Frank-Nodvik equations. Based on the simple method, the various temporal waveform of output pulse with tunable 7 to 20 ns pulse duration can be obtained without interferometric fringes.

  19. Polarization beam combination technique for gain saturation effect compensation in high-energy systems

    NASA Astrophysics Data System (ADS)

    Chen, Junchi; Peng, Yujie; Su, Hongpeng; Leng, Yuxin

    2016-06-01

    To compensate for the gain saturation effect in the high-energy laser amplifier, a modified polarization beam combination (PBC) method is introduced to reshape temporal waveform of the injected laser pulse to obtain a controlled high-energy laser pulse shape after amplification. One linearly polarized beam is divided into two orthogonal polarized beams, which spatially recombine together collinearly after propagating different optical paths with relative time delay in PBC structure. The obtained beam with polarization direction being rotated by the following half wave plate is divided and combined again to reform a new beam in another modified polarization beam structure. The reformed beam is injected into three cascaded laser amplifiers. The amplified pulse shape can be controlled by the incident pulse shape and amplifier gain, which is agreeable to the simulation by the Frank-Nodvik equations. Based on the simple method, the various temporal waveform of output pulse with tunable 7 to 20 ns pulse duration can be obtained without interferometric fringes.

  20. Periodic inversion and phase transition of finite energy Airy beams in a medium with parabolic potential.

    PubMed

    Zhang, Yiqi; Belić, Milivoj R; Zhang, Lei; Zhong, Weiping; Zhu, Dayu; Wang, Ruimin; Zhang, Yanpeng

    2015-04-20

    We study periodic inversion and phase transition of normal, displaced, and chirped finite energy Airy beams propagating in a parabolic potential. This propagation leads to an unusual oscillation: for half of the oscillation period the Airy beam accelerates in one transverse direction, with the main Airy beam lobe leading the train of pulses, whereas in the other half of the period it accelerates in the opposite direction, with the main lobe still leading - but now the whole beam is inverted. The inversion happens at a critical point, at which the beam profile changes from an Airy profile to a Gaussian one. Thus, there are two distinct phases in the propagation of an Airy beam in the parabolic potential - the normal Airy and the single-peak Gaussian phase. The length of the single-peak phase is determined by the size of the decay parameter: the smaller the decay, the smaller the length. A linear chirp introduces a transverse displacement of the beam at the phase transition point, but does not change the location of the point. A quadratic chirp moves the phase transition point, but does not affect the beam profile. The two-dimensional case is discussed briefly, being equivalent to a product of two one-dimensional cases.

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

    NASA Astrophysics Data System (ADS)

    Perry, A.; Ostroumov, P. N.; Barcikowski, A.; Dickerson, C.; Kondrashev, S. A.; Mustapha, B.; Savard, G.

    2015-01-01

    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 3×105 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.

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

    SciTech Connect

    Perry, A.; Ostroumov, P. N.; Barcikowski, A.; Dickerson, C.; Kondrashev, S. A.; Mustapha, B.; Savard, G.

    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.

  3. Alpha-induced reaction studies using low-energy RI beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hu, J.; Kubono, S.; Hayakawa, S.; Hashimoto, T.

    2012-11-01

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Studies on proton and alpha resonance scatterings, (α, p) reactions, and other types of measurements (β-decay lifetimes etc.) have been performed using RI beams at CRIB, motivated by interests on astrophysical reactions and exotic nuclear structure. Among the studies at CRIB, the measurement of 7Li+α/7Be+α resonant scatterings are presented.

  4. Beam position and energy monitoring in compact linear accelerators for radiotherapy.

    PubMed

    Ruf, Marcel; Müller, Sven; Setzer, Stefan; Schmidt, Lorenz-Peter

    2014-02-01

    The experimental verification of a novel sensor topology capable of measuring both the position and energy of an electron beam inside a compact electron linear accelerator for radiotherapy is presented. The method applies microwave sensing techniques and allows for the noninterceptive monitoring of the respective beam parameters within compact accelerators for medical or industrial purposes. A state space feedback approach is described with the help of which beam displacements, once detected, can be corrected within a few system macropulses. The proof-of-principle experiments have been conducted with a prototype accelerator and customized hardware. Additionally, closed-loop operation with high accuracy is demonstrated.

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

    SciTech Connect

    Waldschmidt, G. J.

    1998-10-27

    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].

  6. Alpha-induced reaction studies using low-energy RI beams at CRIB

    SciTech Connect

    Yamaguchi, H.; Kahl, D.; Hu, J.; Kubono, S.; Hayakawa, S.; Hashimoto, T.

    2012-11-12

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Studies on proton and alpha resonance scatterings, ({alpha}, p) reactions, and other types of measurements ({beta}-decay lifetimes etc.) have been performed using RI beams at CRIB, motivated by interests on astrophysical reactions and exotic nuclear structure. Among the studies at CRIB, the measurement of {sup 7}Li+{alpha}/{sup 7}Be+{alpha} resonant scatterings are presented.

  7. Response of a tungsten powder target to an incident high energy proton beam

    NASA Astrophysics Data System (ADS)

    Caretta, O.; Davenne, T.; Densham, C.; Fitton, M.; Loveridge, P.; O'Dell, J.; Charitonidis, N.; Efthymiopoulos, I.; Fabich, A.; Rivkin, L.

    2014-10-01

    The experiment described in this paper is the first study of the response of a static tungsten powder sample to an impinging high energy proton beam pulse. The experiment was carried out at the HiRadMat facility at CERN. Observations include high speed videos of a proton beam induced perturbation of the powder sample as well as data from a laser Doppler vibrometer measuring the oscillations of the powder container. A comparison with a previous analogous experiment which studied a proton beam interaction with mercury is made.

  8. SU-E-T-221: Investigation of Lower Energy (< 6 MV) Photon Beams for Cancer Radiotherapy

    SciTech Connect

    Zhang, Y; Ming, X; Feng, Y; Zhou, L; Ahmad, M; Deng, J; Nguyen, K; Griffin, M

    2014-06-01

    Purpose: To study the potential applications of the lower energy (< 6MV) photon beams in the radiotherapeutic management of pediatric cancer and lung cancer patients. Methods: Photon beams of 2, 3, 4, 5 and 6MV were first simulated with EGS4/BEAM and then used for Monte-Carlo dose calculations. For four pediatric patients with abdominal and brain lesions, six 3D-conformal radiotherapy (3DCRT) plans were generated using single photon energy (2 to 6MV) or mixed energies (3 and 6MV). Furthermore, a virtual machine of 3 and 6MV was commissioned in a treatment planning system (TPS) based on Monte-Carlo simulated data. Three IMRT plans of a lung cancer patient were generated on this virtual machine. All plans were normalized to D95% of target dose for 6MV plan and then compared in terms of integral dose and OAR sparing. Results: For the four pediatric patients, the integral dose for the 2, 3, 4 and 5MV plans increased by 9%, 5%, 3.5%, 1.7%, respectively as compared to 6MV. Almost all OARs in the 2MV plan received more than 10% more doses than 6MV. Mixed energy 3DCRT plans were of the same quality as 6MV plans. For the lung IMRT plans, both the 3MV plan and the mixed beam plan showed better OAR sparing in comparison to 6MV plan. Specifically, the maximum and mean doses to the spinal cord in the mixed energy plan were lower by 21% and 16%, respectively. Conclusion: Single lower energy photon beam was found to be inferior to 6MV in the radiotherapy of pediatric patients and lung cancer patients when the integral doses and the doses to the OARs were considered. However, mixed energy plans combining low with high energy beams showed significant OAR sparing while maintaining the same PTV coverage. Investigation with more patient data is ongoing for further confirmation.

  9. Energy regeneration model of self-consistent field of electron beams into electric power*

    NASA Astrophysics Data System (ADS)

    Kazmin, B. N.; Ryzhov, D. R.; Trifanov, I. V.; Snezhko, A. A.; Savelyeva, M. V.

    2016-04-01

    We consider physic-mathematical models of electric processes in electron beams, conversion of beam parameters into electric power values and their transformation into users’ electric power grid (onboard spacecraft network). We perform computer simulation validating high energy efficiency of the studied processes to be applied in the electric power technology to produce the power as well as electric power plants and propulsion installation in the spacecraft.

  10. The influence of the energy reservoir on the plasma channel in focused femtosecond laser beams

    NASA Astrophysics Data System (ADS)

    Dergachev, A. A.; Ionin, A. A.; Kandidov, V. P.; Mokrousova, D. V.; Seleznev, L. V.; Sinitsyn, D. V.; Sunchugasheva, E. S.; Shlenov, S. A.

    2015-06-01

    The influence of the energy reservoir on plasma channel formation during the filamentation of tightly focused femtosecond laser beams was studied both experimentally and numerically. It was found that for the reservoir localized near the propagation axis, its diameter is much smaller than in the case of a collimated beam and decreases in the vicinity of the focus. A small diaphragm placed in the focal area does not eliminate the plasma channel behind the focal point.

  11. High energy solar beam testing in the JPL 25-ft space simulator

    NASA Technical Reports Server (NTRS)

    Harrell, J. W.

    1975-01-01

    Modifications to the individual components in the solar simulation system to improve performance and reduce costs are described. The improvements include: an increase in lamp power from 20 KW to 30 KW; a family of solar beams from 8 to 18.5 feet in diameter at intensities related to beam size with a maximum intensity of 12 solar constants over a 9 ft. diameter; and up to 1.1 megawatts of simulated solar energy in the lamp array.

  12. Simultaneous cancellation of beam emittance and energy spread in the CEBAF nuclear physics injector chopping system

    SciTech Connect

    Liu, H.; Bisognano, J.

    1993-06-01

    The CEBAF nuclear physics injector will utilize a unique chopping system consisting of two identical square box RF cavities with an inverting lens and a chopper aperture in-between. This system produces three interleaved 499 MHz cw electron beams from a 100 kV input beam. In this paper, we present our theoretical and numerical studies on how both emittance and energy spread are cancelled simultaneously in the dechopping process in the second cavity.

  13. Resonant principle for operation of energy recuperator for a magnetized electron beam: A numerical simulation

    NASA Astrophysics Data System (ADS)

    Arzhannikov, A. V.; Astrelin, V. T.; Koidan, V. S.; Sinitsky, S. L.

    2002-04-01

    The problem of energy recuperator for a high current sheet electron beam used to drive a millimeter-waves generator is considered. There are two main obstacles to solving the problem. The first one is the presence of a magnetic field guiding beam electrons. The second obstacle is significant energy and angular spreads of the electrons in the waste beam. To overcome these obstacles, we suggest a novel scheme of a recuperator. The main idea of the proposed scheme is the use of a decelerating electrical field together with a guiding magnetic field that has longitudinal and spatial periodic transverse components. Resonance of a bounce electron motion with the cyclotron motion in this field gives a strong increase in the Larmour radius of electrons with the energy in a narrow interval. The decelerated electrons with the resonance energy fall away from the beam and are absorbed by a collector at a proper potential. It is shown that efficiency of this novel scheme can reach about 80% even if the sheet beam has a broad energy spectrum.

  14. Measurement and Analysis of Rotational Energy of Nitrogen Molecular Beam by REMPI

    SciTech Connect

    Mori, H.; Yamaguchi, H.; Kataoka, K.; Sugiyama, N.; Ide, K.; Niimi, T.

    2008-12-31

    Molecular beams are powerful tools for diagnoses of solid surfaces and gas-surface interaction tests. Unfortunately, there are very few reports about experimental analysis of internal energy distribution (e.g. rotational energy) of molecular beams of diatomic or polyatomic molecules, because measurement of internal energy distribution is very difficult. Spectroscopic measurement techniques based on resonantly enhanced multiphoton ionization (REMPI) is very powerful for measurement in highly rarefied gas flows. In this study, the REMPI method is applied to measurement of rotational energy distribution of nitrogen molecular beams. The REMPI spectrum of the molecular beam indicates the rotational temperature higher than the translational temperature of 7.2 K estimated by assuming isentropic flows. The O and P branches of the REMPI spectrum correspond to the rotational temperature of 30 K, but the S branch of the spectrum deviates from that at 30 K. It seems to be because the non-equilibrium rotational energy distribution of the molecular beam deviates from the Boltzmann distribution.

  15. Ultra-low-energy (<10 eV/u) ion beam bombardment effect on naked DNA

    NASA Astrophysics Data System (ADS)

    Thopan, P.; Thongkumkoon, P.; Prakrajang, K.; Suwannakachorn, D.; Yu, L. D.

    2014-05-01

    Since ion energy deposition in the ion-bombarded materials dominantly occurs in the low-energy range, it is very interesting to know effects from ultra-low-energy ion interaction with DNA for understanding ion-beam-induced genetic mutation. Tens-keV Ar- and N-ion beams were decelerated to ultra-low energy ranging from 20 to 100 eV, or only a few to 10 eV/u, to bombard naked plasmid DNA. The bombarded DNA was analyzed using gel electrophoresis for DNA form changes. The original DNA supercoiled form was found to change to relaxed and linear forms, indicating single or double strand breaks after bombarded by tens-eV ion beam. N-ion beam was found more effective in inducing DNA change and mutation than Ar-ion beam. The study demonstrated that the ion bombardment with energy as low as several-tens eV was able to break DNA strands and thus potentially to cause genetic modification of biological cells. The experimental results were discussed in terms of direct atomic collision between the ions and DNA atoms.

  16. Generation of a pulsed low-energy electron beam using the channel spark device

    SciTech Connect

    Elgarhy, M. A. I. Hassaballa, S. E.; Rashed, U. M.; ElSabbagh, M. M.; Saudy, A. H.; Soliman, H. M.

    2015-12-15

    For the generation of low-energy electron beam, the design and characteristics of channel spark discharge (CSD) operating at a low voltage are presented in this paper. The discharge voltage, discharge current, X-ray emissions, and electron beam current were experimentally determined. The effects of the applied voltage, working gas pressure, and external capacitance on the CSD and beam parameters were measured. At an applied voltage of 11 kV, an oxygen gas pressure of 25 mTorr, and an external capacitance of 16.45 nF, the maximum measured current was 900 A. The discharge current increased with the increase in the pressure and capacitance, while its periodic time decreased with the increase in the pressure. Two types of the discharge were identified and recorded: the hollow cathode discharge and the conduction discharge. A Faraday cup was used to measure the beam current. The maximum measured beam current was 120 A, and the beam signal exhibited two peaks. The increase in both the external capacitance and the applied discharge voltage increased the maximum electron beam current. The electron-beam pulse time decreased with the increase in the gas pressure at a constant voltage and increased with the decrease in the applied discharge voltage. At an applied voltage of 11 kV and an oxygen gas pressure of 15 mTorr, the maximum beam energy was 2.8 keV. The X-ray signal intensity decreased with the increase in the gas pressure and increased with the increase in the capacitance.

  17. Generation of a pulsed low-energy electron beam using the channel spark device.

    PubMed

    Elgarhy, M A I; Hassaballa, S E; Rashed, U M; ElSabbagh, M M; Soliman, H M; Saudy, A H

    2015-12-01

    For the generation of low-energy electron beam, the design and characteristics of channel spark discharge (CSD) operating at a low voltage are presented in this paper. The discharge voltage, discharge current, X-ray emissions, and electron beam current were experimentally determined. The effects of the applied voltage, working gas pressure, and external capacitance on the CSD and beam parameters were measured. At an applied voltage of 11 kV, an oxygen gas pressure of 25 mTorr, and an external capacitance of 16.45 nF, the maximum measured current was 900 A. The discharge current increased with the increase in the pressure and capacitance, while its periodic time decreased with the increase in the pressure. Two types of the discharge were identified and recorded: the hollow cathode discharge and the conduction discharge. A Faraday cup was used to measure the beam current. The maximum measured beam current was 120 A, and the beam signal exhibited two peaks. The increase in both the external capacitance and the applied discharge voltage increased the maximum electron beam current. The electron-beam pulse time decreased with the increase in the gas pressure at a constant voltage and increased with the decrease in the applied discharge voltage. At an applied voltage of 11 kV and an oxygen gas pressure of 15 mTorr, the maximum beam energy was 2.8 keV. The X-ray signal intensity decreased with the increase in the gas pressure and increased with the increase in the capacitance. PMID:26724026

  18. Myocardial signal density levels and beam-hardening artifact attenuation using dual-energy computed tomography.

    PubMed

    Rodriguez-Granillo, Gaston A; Carrascosa, Patricia; Cipriano, Silvina; de Zan, Macarena; Deviggiano, Alejandro; Capunay, Carlos; Cury, Ricardo C

    2015-01-01

    The assessment of myocardial perfusion using single-energy (SE) imaging is influenced by beam-hardening artifacts (BHA). We sought to explore the ability of dual-energy (DE) imaging to attenuate the presence of BHA. Myocardial signal density (SD) was evaluated in 2240 myocardial segments (112 for each energy level) and in 320 American Heart Association segments among the SE group. Compared to DE reconstructions at the best energy level, SE acquisitions showed no significant differences overall regarding myocardial SD or signal-to-noise ratio. The segments most commonly affected by BHA showed significantly lower myocardial SD at the lowest energy levels, progressively normalizing at higher energy levels.

  19. Energy straggling of low-energy ion beam in a charge exchange cell for negative ion production

    SciTech Connect

    Takeuchi, S.; Sasao, M.; Sugawara, H.; Tanaka, N.; Kisaki, M.; Okamoto, A.; Shinto, K.; Kitajima, S.; Nishiura, M.; Wada, M.

    2008-02-15

    Energy straggling in a charge exchange cell, which is frequently used for negative ion production, was studied experimentally and compared with the results of theoretical evaluation. The change of the energy spectrum of a He{sup +} beam due to charge exchange processes in argon gas was measured in the energy range of 2-6 keV. Energy straggling by multiple collisions is expressed by the energy loss formula due to inelastic and elastic processes. The impact parameter is related to the elastic scattering angle, and the geometry of the charge exchange cell and other components of the beam transportation system determines the maximum acceptable scattering angle. The energy spread was evaluated taking the integral limit over the impact parameter into consideration. The theoretical results showed good agreement with those of actual measurement.

  20. Rare isotope beam energy measurements and scintillator developments for ReA3

    NASA Astrophysics Data System (ADS)

    Lin, Ling-Ying

    The ReAccelerator for 3 MeV/u beams (ReA3) at the National Superconducting Cyclotron Laboratory (NSCL) in Michigan State University can stop rare isotope beams produced by in-flight fragmentation and reaccelerate them in a superconducting linac. The precise knowledge of the energy and the energy spread of the ion beams extracted from the ReA3 linac is essential for experimental requirement in many applications. Beam energy determination methods such as implantation on a Si detector and/or using calibrated linac settings are precise within a few tens of keV/u. In order to determine beam energies with good resolution of less than 0.5 % FWHM, a 45 degree bending magnet with a movable slit is used to determine the absolute beam energy based on the magnetic rigidity. Two methods have been developed for the energy calibration of the beam analyzing magnet: gamma-ray nuclear resonance reactions and a time-of-flight (TOF) technique. The resonance energies of gamma-ray resonant reactions provide well-known and precise calibration points. The gamma ray yields of the 27Al(p,gamma)28Si at Ep= 992 keV and 632 keV resonances and 58Ni(p,gamma)59Cu at Ep= 1843 keV resonance have been measured with the high efficiency CAESAR (CAESium iodide ARray) and SuN (Summing NaI(Tl)) detectors. By fitting the observed resonant gamma-ray yields, not only the beam energy can be precisely correlated with the magnetic field but also beam energy spread can be obtained. The measured beam energy spread is consistent with beam optics calculations. A time-of-flight system for determining the absolute energy of ion beams and calibrating the 45 degree magnetic analyzer has been developed in ReA3 by using two identical secondary electron monitors (grid-MCP detectors) with appropriate separation. The TOF technique is applicable to the variety of beam energies and ion particles. Velocities of ion beam are determined by simultaneously measuring the arrival time of beam bunches at the two detectors with

  1. Exploiting neutron-rich radioactive ion beams to constrain the symmetry energy

    NASA Astrophysics Data System (ADS)

    Kohley, Z.; Christian, G.; Baumann, T.; DeYoung, P. A.; Finck, J. E.; Frank, N.; Jones, M.; Smith, J. K.; Snyder, J.; Spyrou, A.; Thoennessen, M.

    2013-10-01

    The Modular Neutron Array (MoNA) and 4 Tm Sweeper magnet were used to measure the free neutrons and heavy charged particles from the radioactive ion beam induced 32Mg+9Be reaction. The fragmentation reaction was simulated with the constrained molecular dynamics model (CoMD), which demonstrated that the of the heavy fragments and free neutron multiplicities were observables sensitive to the density dependence of the symmetry energy at subsaturation densities. Through comparison of these simulations with the experimental data, constraints on the density dependence of the symmetry energy were extracted. The advantage of radioactive ion beams as a probe of the symmetry energy is demonstrated through examination of CoMD calculations for stable and radioactive-beam-induced reactions.

  2. High-Energy Molecular Beam Source Using a Non-Diaphragm Type Small Shock Tube

    NASA Astrophysics Data System (ADS)

    Yoshimoto, Yuta; Miyoshi, Nobuya; Kinefuchi, Ikuya; Shimizu, Kazuya; Takagi, Shu; Matsumoto, Yoichiro

    2010-11-01

    The molecular beam technique is one of the powerful tools to analyze gas-surface interactions. In order to generate high-energy molecular beam in a range of 1 - 5 eV, which corresponds to the typical activation energy of surface reactions, we are developing a beam source using a non-diaphragm type shock tube, which can operate at a repetition rate high enough for efficient data acquisition. We made the volume of a tube much smaller than that of conventional ones so that the evacuation time between each shot becomes as short as possible. Our measurement of shock Mach numbers showed that even small diameter (2 or 4 mm) tubes, in which the wall boundary layer has a large influence on the propagation of shock waves, could generate molecular beam with the translational energy of more than 1 eV. This is because the reduction of shock formation distance by rapid opening of the valve, which separates a high pressure room from a low pressure room, weakened the effect of viscous damping on the accelerating shock wave. In addition, the convergent shock tubes of which diameters linearly decrease from 4 to 2 mm exhibited higher Mach numbers than straight ones. This indicates that the application of the convergent tube with the optimized geometry would be promising for generating high-energy molecular beam.

  3. Physics of Neutralization of Intense High-Energy Ion Beam Pulses by Electrons

    SciTech Connect

    Kaganovich, I. D.; Davidson, R. C.; Dorf, M. A.; Startsev, E. A.; Sefkow, A. B.; Lee, E. P.; Friedman, A.

    2010-04-28

    Neutralization and focusing of intense charged particle beam pulses by electrons forms the basis for a wide range of applications to high energy accelerators and colliders, heavy ion fusion, and astrophysics. For example, for ballistic propagation of intense ion beam pulses, background plasma can be used to effectively neutralize the beam charge and current, so that the self-electric and self- magnetic fields do not affect the ballistic propagation of the beam. From the practical perspective of designing advanced plasma sources for beam neutralization, a robust theory should be able to predict the self-electric and self-magnetic fields during beam propagation through the background plasma. The major scaling relations for the self-electric and self-magnetic fields of intense ion charge bunches propagating through background plasma have been determined taking into account the effects of transients during beam entry into the plasma, the excitation of collective plasma waves, the effects of gas ionization, finite electron temperature, and applied solenoidal and dipole magnetic fields. Accounting for plasma production by gas ionization yields a larger self-magnetic field of the ion beam compared to the case without ionization, and a wake of current density and self-magnetic field perturbations is generated behind the beam pulse. A solenoidal magnetic field can be applied for controlling the beam propagation. Making use of theoretical models and advanced numerical simulations, it is shown that even a small applied magnetic field of about 100G can strongly affect the beam neutralization. It has also been demonstrated that in the presence of an applied magnetic field the ion beam pulse can excite large-amplitude whistler waves, thereby producing a complex structure of self-electric and self-magnetic fields. The presence of an applied solenoidal magnetic field may also cause a strong enhancement of the radial self-electric field of the beam pulse propagating through the

  4. Physics of neutralization of intense high-energy ion beam pulses by electrons

    SciTech Connect

    Kaganovich, I. D.; Davidson, R. C.; Dorf, M. A.; Startsev, E. A.; Sefkow, A. B.; Lee, E. P.; Friedman, A.

    2010-05-15

    Neutralization and focusing of intense charged particle beam pulses by electrons form the basis for a wide range of applications to high energy accelerators and colliders, heavy ion fusion, and astrophysics. For example, for ballistic propagation of intense ion beam pulses, background plasma can be used to effectively neutralize the beam charge and current, so that the self-electric and self-magnetic fields do not affect the ballistic propagation of the beam. From the practical perspective of designing advanced plasma sources for beam neutralization, a robust theory should be able to predict the self-electric and self-magnetic fields during beam propagation through the background plasma. The major scaling relations for the self-electric and self-magnetic fields of intense ion charge bunches propagating through background plasma have been determined taking into account the effects of transients during beam entry into the plasma, the excitation of collective plasma waves, the effects of gas ionization, finite electron temperature, and applied solenoidal and dipole magnetic fields. Accounting for plasma production by gas ionization yields a larger self-magnetic field of the ion beam compared to the case without ionization, and a wake of current density and self-magnetic field perturbations is generated behind the beam pulse. A solenoidal magnetic field can be applied for controlling the beam propagation. Making use of theoretical models and advanced numerical simulations, it is shown that even a small applied magnetic field of about 100 G can strongly affect the beam neutralization. It has also been demonstrated that in the presence of an applied magnetic field the ion beam pulse can excite large-amplitude whistler waves, thereby producing a complex structure of self-electric and self-magnetic fields. The presence of an applied solenoidal magnetic field may also cause a strong enhancement of the radial self-electric field of the beam pulse propagating through the

  5. Output beam energy measurement of a 100-MeV KOMAC drift tube linac by using a stripline beam position monitor

    NASA Astrophysics Data System (ADS)

    Kim, Han-Sung

    2015-10-01

    The 100-MeV proton linac at the KOMAC (Korea Multi-purpose Accelerator Complex) is composed of a 50-keV proton injector, a 3-MeV RFQ (radio-frequency quadrupole) and a 100-MeV DTL (drift tube linac). The proton beam is accelerated from 3 MeV to 100 MeV through 11 DTL tanks. The precise measurement of the proton-beam's energy at the output of each DTL tank is important for the longitudinal beam dynamics and can be performed by using a time-of-flight method with a BPM (beam position monitor), which is installed between each DTL tank. The details of the output beam energy measurement of the KOMAC DTL with stripline-type BPM and BPM signal processing, along with a comparison with the simulation results, will be presented in this paper.

  6. Recent U.S. advances in ion-beam-driven high energy densityphysics and heavy ion fusion

    SciTech Connect

    Logan, B.G.; Bieniosek, F.M.; Celata, C.M.; Coleman, J.; Greenway, W.; Henestroza, E.; Kwan, J.W.; Lee, E.P.; Leitner, M.; Roy,P.K.; Seidl, P.A.; Vay, J-L.; Waldron, W.L.; Yu, S.S.; Barnard, J.J.; Cohen, R.H.; Friedman, A.; Grote, D.P.; Kireeff Covo, M.; Molvik, A.W.; Lund, S.M.; Meier, W.R.; Sharp, W.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Grisham, L.; Kaganovich, Qin H.; Sefkow, A.B.; Startsev,E.A.; Welch, D.; Olson, C.

    2006-07-05

    During the past two years, significant experimental and theoretical progress has been made in the US heavy ion fusion science program in longitudinal beam compression, ion-beam-driven warm dense matter, beam acceleration, high brightness beam transport; and advanced theory and numerical simulations. Innovations in longitudinal compression of intense ion beams by > 50 X propagating through background plasma enable initial beam target experiments in warm dense matter to begin within the next two years. They are assessing how these new techniques might apply to heavy ion fusion drivers for inertial fusion energy.

  7. Low-Energy E-Beam Proximity Lithography (LEEPL): Is the Simplest the Best?

    NASA Astrophysics Data System (ADS)

    Utsumi, Takao

    1999-12-01

    Low-energy e-beam proximity lithography (LEEPL) is proposed as the simplest integrated circuit lithography for minimum feature sizes ≤0.1 µm. This new e-beam lithography is similar to 1× X-ray proximity lithography except that the X-ray beam is replaced with a beam of low-energy electrons of 2 kV. This low e-beam energy permits the use of single-crystal 0.5-µm-thick silicon stencil masks without an absorbing metal layer of high atomic number. This membrane mask is thick enough for good heat conduction and thin enough for feature sizes ≤0.1 µm. Mask distortion caused by fabrication can be corrected by a fine-tuning deflector. Therefore, a mask with a residual distortion of more than 100 nm is acceptable. This eliminates the main difficulty of X-ray proximity lithography. The proposed system is not affected by a space-charge effect in the electron optics column, and a proximity effect with respect to both wafer and mask writings, and it is fundamentally low-power lithography which needs no special cooling system. The analysis shows that the e-beam column can be made entirely of electrostatic components to achieve sufficient resolution. For an appropriate resist process for this low-energy e-beam, we propose a bilayer process such as the chemical amplification of resist lines (CARL) process which consists of a chemically amplified thin deep ultraviolet (DUV) photoresist and a thick planarizing layer as a starting point. We estimated a throughput of about 40 12 inch wafers per hour and a resolution of a significantly less than 50 nm.

  8. U.S. Heavy Ion Beam Science towards inertial fusion energy

    SciTech Connect

    Logan, B.G.; Baca, D.; Barnard, J.J.; Bieniosek, F.M.; Burkhart, C.; Celata, C.M.; Chacon-Golcher, E.; Cohen, R.H.; Davidson, R.C.; Efthimion P.; Faltens, A.; Friedman, A.; Grisham, L.; Grote, D.P.; Haber, I.; Henestroza, E.; Kaganovich, I.; Kishek, R.A.; Kwan, J.W.; Lee, E.P.; Lee, W.W.; Leitner, M.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; O'Shea, P.G.; Olson, C.; Olson, R.E.; Prost, L.R.; Qin, H.; Reiser, M.; Rose, D.; Sabbi, G.; Seidl, P.A.; Sharp, W.M.; Shuman, D.B.; Vay, J-L.; Waldron, W.L.; Welch, D.; Westenskow, G.A.; Yu, S.S.

    2002-10-01

    Significant experimental and theoretical progress in the U.S heavy-ion fusion (HIF) program is reported in modeling and measurements of intense space-charge-dominated heavy ion and electron beams. Measurements of the transport of a well-matched and aligned high current (0.2A) 1.0 MeV potassium ion beam through 10 electric quadrupoles, with a fill factor of 60%, shows no emittance growth within experimental measurement uncertainty, as expected from the simulations. Another experiment shows that passing a beam through an aperture can reduce emittance to near the theoretical limits, and that plasma neutralization of the beam's space-charge can greatly reduce the focal spot radius. Measurements of intense beamlet current density, emittance, charge-state purity, and energy spread from a new, high-brightness, Argon plasma source for HIF experiments are described. New theory and simulations of neutralization of intense beam space charge with plasma in various focusing chamber configurations indicate that near-emittance-limited beam focal spot sizes can be obtained even with beam perveance an order of magnitude higher than in earlier HIF focusing experiments.

  9. Determination of neutral beam energy fractions from collisional radiative measurements on DIII-D.

    PubMed

    Thomas, D M; Grierson, B A; Muñoz Burgos, J M; Van Zeeland, M A

    2012-10-01

    Neutral beams based on positive ion source technology are a key component of contemporary fusion research. An accurate assessment of the injected beam species mix is important for determining the actual plasma heating and momentum input as well as proper interpretation of beam-based diagnostics. On DIII-D, the main ion charge-exchange spectroscopy system is used to extract well-resolved intensity ratios of the Doppler-shifted D(α) emission from the full, half, and third energy beam components for a variety of beam operational parameters. In conjunction with accurate collisional-radiative modeling, these measurements indicate the assumed species mix and power fractions can vary significantly and should be regularly monitored and updated for the most accurate interpretation of plasma performance. In addition, if stable active control of the power fractions can be achieved through appropriate source tuning, the resulting control over the deposition profile can serve as an additional experimental knob for advanced tokamak studies, e.g., varying the off axis beam current drive without altering the beam trajectory.

  10. Vibration energy harvesting by a Timoshenko beam model and piezoelectric transducer

    NASA Astrophysics Data System (ADS)

    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.

  11. A pepper-pot emittance meter for low-energy heavy-ion beams

    SciTech Connect

    Kremers, H. R.; Beijers, J. P. M.; Brandenburg, S.

    2013-02-15

    A novel emittance meter has been developed to measure the four-dimensional, transverse phase-space distribution of a low-energy ion beam using the pepper-pot technique. A characteristic feature of this instrument is that the pepper-pot plate, which has a linear array of holes in the vertical direction, is scanned horizontally through the ion beam. This has the advantage that the emittance can also be measured at locations along the beam line where the beam has a large horizontal divergence. A set of multi-channel plates, scintillation screen, and ccd camera is used as a position-sensitive ion detector allowing a large range of beam intensities that can be handled. This paper describes the design, construction, and operation of the instrument as well as the data analysis used to reconstruct the four-dimensional phase-space distribution of an ion beam. Measurements on a 15 keV He{sup +} beam are used as an example.

  12. Ionosphere/microwave beam interaction study. [satellite solar energy conversion

    NASA Technical Reports Server (NTRS)

    Duncan, L. M.; Gordon, W. E.

    1977-01-01

    A solar power satellite microwave power density of 20mw sq cm was confirmed as the level where nonlinear interactions may occur in the ionosphere, particularly at 100 km altitude. Radio wave heating at this altitude, produced at the Arecibo Observatory, yielded negative results for radio wave heating of an underdense ionosphere. Overdense heating produced striations in the ionosphere which may cause severe radio frequency interference problems under certain conditions. The effects of thermal self-focusing are shown to be limited severely geographically. The aspect sensitivity of field-aligned striations makes interference-free regions above magnetic latitude about 60 deg. A test program is proposed to simulate the interaction of the SPS beam with the ionosphere, to measure the effects of the interaction on the ionosphere and on communication and navigation systems, and to interpret the results.

  13. Studies on low energy beam transport for high intensity high charged ions at IMP

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Sun, L. T.; Hu, Q.; Cao, Y.; Lu, W.; Feng, Y. C.; Fang, X.; Zhang, X. Z.; Zhao, H. W.; Xie, D. Z.

    2014-02-01

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18-24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.

  14. Diagnosing Cross-Beam Energy Transfer Using Beamlets of Unabsorbed Light from Direct-Drive Implosions

    NASA Astrophysics Data System (ADS)

    Edgell, D. H.; Follett, R. K.; Goncharov, V. N.; Igumenshchev, I. V.; Katz, J.; Myatt, J. F.; Seka, W.; Froula, D. H.

    2015-11-01

    A new diagnostic is now being fielded to record the unabsorbed laser light from implosions on OMEGA. Unabsorbed light from each OMEGA beam is imaged as a distinct ``spot'' in time-integrated images. Each spot is, in essence, the end point of a beamlet of light that originates from a specific region of a beam profile and follows a path determined by refraction. The intensity of light in the beamlet varies along that path because of absorption and cross-beam energy transfer (CBET) with other beamlets. This diagnostic allows for the detailed investigation of the effects of CBET on specific locations of the beam profile. A pinhole can be used to isolate specific spots, allowing the time-resolved spectrum of the beamlet to be measured. A fully 3-D CBET hydrodynamics code postprocessor is used to model the intensity and wavelength of each beamlet as it traverses the coronal plasma to the diagnostic. The model predicts that if a single beam in a symmetric implosion is turned off, the recorded intensity of nearby spots will decrease by ~ 15% as a result of loss of CBET from the dropped beam. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  15. Studies on low energy beam transport for high intensity high charged ions at IMP

    SciTech Connect

    Yang, Y. Lu, W.; Fang, X.; Sun, L. T.; Hu, Q.; Cao, Y.; Feng, Y. C.; Zhang, X. Z.; Zhao, H. W.; Xie, D. Z.

    2014-02-15

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18–24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.

  16. Nuclear fragmentation of high-energy heavy-ion beams in water.

    PubMed

    Schardt, D; Schall, I; Geissel, H; Irnich, H; Kraft, G; Magel, A; Mohar, M F; Munzenberg, G; Nickel, F; Scheidenberger, C; Schwab, W; Sihver, L

    1996-01-01

    As a part of the physical-technical program of the heavy-ion therapy project at GSI we have investigated the nuclear fragmentation of high-energy ion beams delivered by the heavy-ion synchrotron SIS, using water as a tissue-equivalent target. For a direct comparison of fragmentation properties, beams of 10B, 12C, 14N, and 16O were produced simultaneously as secondary beams from a primary 18O beam and separated in flight by magnetic beam analysis. The Z-distributions of beam fragments produced in the water target were measured via energy loss in a large ionisation chamber and a scintillator telescope. From these data we obtained both total and partial charge-changing cross sections. In addition we have performed Bragg measurements using two parallel-plate ionization chambers and a water target of variable length. The detailed shape of the measured Bragg curves and the measured cross sections are in good agreement with model calculations based on semi-empirical formulae.

  17. Inertial fusion energy target injection, tracking, and beam pointing

    SciTech Connect

    Petzoldt, R.W.

    1995-03-07

    Several cryogenic targets must be injected each second into a reaction chamber. Required target speed is about 100 m/s. Required accuracy of the driver beams on target is a few hundred micrometers. Fuel strength is calculated to allow acceleration in excess of 10,000 m/s{sup 2} if the fuel temperature is less than 17 K. A 0.1 {mu}m thick dual membrane will allow nearly 2,000 m/s{sup 2} acceleration. Acceleration is gradually increased and decreased over a few membrane oscillation periods (a few ms), to avoid added stress from vibrations which could otherwise cause a factor of two decrease in allowed acceleration. Movable shielding allows multiple targets to be in flight toward the reaction chamber at once while minimizing neutron heating of subsequent targets. The use of multiple injectors is recommended for redundancy which increases availability and allows a higher pulse rate. Gas gun, rail gun, induction accelerator, and electrostatic accelerator target injection devices are studied, and compared. A gas gun is the preferred device for indirect-drive targets due to its simplicity and proven reliability. With the gas gun, the amount of gas required for each target (about 10 to 100 mg) is acceptable. A revolver loading mechanism is recommended with a cam operated poppet valve to control the gas flow. Cutting vents near the muzzle of the gas gun barrel is recommended to improve accuracy and aid gas pumping. If a railgun is used, we recommend an externally applied magnetic field to reduce required current by an order of magnitude. Optical target tracking is recommended. Up/down counters are suggested to predict target arrival time. Target steering is shown to be feasible and would avoid the need to actively point the beams. Calculations show that induced tumble from electrostatically steering the target is not excessive.

  18. Energy-angle correlation of electrons accelerated by laser beam in vacuum

    SciTech Connect

    Chen, Z.; Ho, Y.K.; Xie, Y.J.; Zhang, S.Y.; Yan, Z.; Xu, J.J.; Lin, Y.Z.; Hua, J.F.

    2004-09-27

    The correlation between the outgoing energy and the scattering angle of electrons accelerated by a laser beam in vacuum has been investigated. Essentially, the single-valued function of the correlation, derived from classical electrodynamics Compton scattering for a plane wave, is broadened to a band. It means electrons with the same outgoing energy will have an angular spread. An equation to describe this correlation has been derived. Dependence of the spread width of scattering angle on laser beam parameters is examined, and physical explanations of these features are given. The results are found to be consistent with the simulation results for a proposed vacuum laser acceleration scheme: the capture and acceleration scenario.

  19. On the energy dependence of proton beam extraction with a bent crystal

    NASA Astrophysics Data System (ADS)

    Arduini, G.; Elsener, K.; Fidecaro, G.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Weisse, E.

    1998-03-01

    Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators. © 1998

  20. Proposed Molecular Beam Determination of Energy Partition in the Photodissociation of Polyatomic Molecules

    DOE R&D Accomplishments Database

    Zare, P. N.; Herschbach, D. R.

    1964-01-29

    Conventional photochemical experiments give no information about the partitioning of energy between translational recoil and internal excitation of the fragment molecules formed in photodissociation of a polyatomic molecule. In a molecular beam experiment, it becomes possible to determine the energy partition from the form of the laboratory angular distribution of one of the photodissociation products. A general kinematic analysis is worked out in detail, and the uncertainty introduced by the finite angular resolution of the apparatus and the velocity spread in the parent beam is examined. The experimental requirements are evaluated for he photolysis of methyl iodide by the 2537 angstrom Hg line.

  1. The influence of beam energy and oxidation on quantitative carbide analysis in the scanning electron microscope

    SciTech Connect

    Rodenburg, C.; Rainforth, W. M.

    2006-12-01

    In this paper the origin of the carbide/matrix contrast in secondary electron images and its ramifications for spatial resolution are investigated. A profound influence of the backscattered electron yield and the oxidation of the steel matrix was found, which manifests itself in a contrast reversal at low primary electron beam energies. The authors established that low beam energies are necessary to obtain the required spatial resolution. Strategies for optimizing the contrast between carbide and matrix in secondary electron images without compromising the spatial resolution are presented. A simple method to estimate the thickness of thin oxide layers from low voltage secondary electron images is also described.

  2. Two-Screen Method for Determining Electron Beam Energy and Deflection from Laser Wakefield Acceleration

    SciTech Connect

    Pollock, B B; Ross, J S; Tynan, G R; Divol, L; Glenzer, S H; Leurent, V; Palastro, J P; Ralph, J E; Froula, D H; Clayton, C E; Marsh, K A; Pak, A E; Wang, T L; Joshi, C

    2009-04-24

    Laser Wakefield Acceleration (LWFA) experiments have been performed at the Jupiter Laser Facility, Lawrence Livermore National Laboratory. In order to unambiguously determine the output electron beam energy and deflection angle at the plasma exit, we have implemented a two-screen electron spectrometer. This system is comprised of a dipole magnet followed by two image plates. By measuring the electron beam deviation from the laser axis on each plate, both the energy and deflection angle at the plasma exit are determined through the relativistic equation of motion.

  3. Removing THMs from drinking water using high-energy electron-beam irradiation

    SciTech Connect

    Cooper, W.J.; Cadavid, E.M.; Nickelson, M.G.; Lin, K. ); Kurucz, C.N.; Waite, T.D. )

    1993-09-01

    High-energy electron-beam irradiation was shown to be efficient for removing trihalomethanes (THMs) from drinking water. The process was demonstrated on a 1.5-MeV variable-current (0--50 mA) electron-beam system at a flow rate of 120 gpm and on a [sup 60]Co gamma source. Of the four THMs, chloroform was the most difficult, i.e., energy-intensive, to remove. The brominated THMs were much more efficiently destroyed by the process. Organically bound halogens were converted to halide anions, and no organic halogen or oxyhalogen reaction by-products were observed.

  4. Compact disposal of high-energy electron beams using passive or laser-driven plasma decelerating stage

    SciTech Connect

    Bonatto, A.; Schroeder, C. B.; Vay, J. -L.; Geddes, C. R.; Benedetti, C.; Esarey and, E.; Leemans, W. P.

    2014-07-13

    A plasma decelerating stage is investigated as a compact alternative for the disposal of high-energy beams (beam dumps). This could benefit the design of laser-driven plasma accelerator (LPA) applications that require transportability and or high-repetition-rate operation regimes. Passive and laser-driven (active) plasma-based beam dumps are studied analytically and with particle-in-cell (PIC) simulations in a 1D geometry. Analytical estimates for the beam energy loss are compared to and extended by the PIC simulations, showing that with the proposed schemes a beam can be efficiently decelerated in a centimeter-scale distance.

  5. Numerical studies of the Weibel Instability in Intense Charged Particle Beams with Large Energy Anisotropy

    NASA Astrophysics Data System (ADS)

    Lee, Wei-Li; Startsev, Edward A.; Davidson, Ronald C.

    2004-11-01

    In intense charged particle beams with large temperature anisotropy free energy is available to drive a transverse electromagnetic Weibel-type instability. The finite transverse geometry of the confined beam makes a detailed theoretical investigation difficult. In this paper the newly developed bEASt (beam eigenmode and spectra) code which solves the linearized Vlasov-Maxwell equations is used to investigate the detailed properties of the Weibel instability for a long charge bunch propagating through a cylindrical pipe of radius r_w. The stability analysis is carried out for azimuthally symmetric perturbations about a two-temperature thermal equilibrium distribution in the smooth-focusing approximation. To study the nonlinear stage of the instability, the Darwin model is being developed and incorporated into the Beam Equilibrium Stability and Transport(BEST) code.

  6. Low energy ion beam induced changes in structural and thermal properties of polycarbonate

    NASA Astrophysics Data System (ADS)

    Reheem, A. M. Abdel; Atta, A.; Maksoud, M. I. A. Abdel

    2016-10-01

    The aim of the present study is extended for obtaining relation between the collision of ion beam with polycarbonate polymer (PC) and the introduced modification of technological applications. Polycarbonate films are irradiated by a 6 keV argon ion beam extracted from locally design cold cathode ion source with different ion fluences. The films are characterized using X-ray Diffraction (XRD), Mechanical tester, Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). The increase in ion beam irradiation leads to an increase in the tensile strength and reduction in elongation at break for PC. TGA Analysis shows that the thermal decomposition temperature of irradiated polycarbonate changes with ion fluence. The DSC graphs show improvements in thermal stability with increase in the activation energy after ion beam irradiation. Ion penetration depths and distributions of scattered atoms are calculated using SRIM Monte Carlo simulation programs.

  7. Device and method for generating a beam of acoustic energy from a borehole, and applications thereof

    DOEpatents

    Vu, Cung Khac; Sinha, Dipen N; Pantea, Cristian; Nihei, Kurt T; Schmitt, Denis P; Skelt, Christopher

    2013-10-01

    In some aspects of the invention, a method of generating a beam of acoustic energy in a borehole is disclosed. The method includes generating a first acoustic wave at a first frequency; generating a second acoustic wave at a second frequency different than the first frequency, wherein the first acoustic wave and second acoustic wave are generated by at least one transducer carried by a tool located within the borehole; transmitting the first and the second acoustic waves into an acoustically non-linear medium, wherein the composition of the non-linear medium produces a collimated beam by a non-linear mixing of the first and second acoustic waves, wherein the collimated beam has a frequency based upon a difference between the first frequency and the second frequency; and transmitting the collimated beam through a diverging acoustic lens to compensate for a refractive effect caused by the curvature of the borehole.

  8. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    SciTech Connect

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-12-01

    In heavy ion inertial fusion energy systems, intense beams of ions must be transported from the exit of the final focus magnet system through the target chamber to hit millimeter spot sizes on the target. In this paper, we examine three different modes of beam propagation: neutralized ballistic transport, assisted pinched transport, and self-pinched transport. The status of our understanding of these three modes is summarized, and the constraints imposed by beam propagation upon the chamber environment, as well as their compatibility with various chamber and target concepts, are considered. We conclude that, on the basis of our present understanding, there is a reasonable range of parameter space where beams can propagate in thick-liquid wall, wetted-wall, and dry-wall chambers.

  9. Issues concerning high current lower energy electron beams required for ion cooling between EBIS LINAC and booster

    SciTech Connect

    Hershcovitch,A.

    2009-03-01

    Some issues, regarding a low energy high current electron beam that will be needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, are examined. Options for propagating such an electron beam, as well as the effect of neutralizing background plasma on electron and ion beam parameters are calculated. Computations and some experimental data indicate that none of these issues is a show stopper.

  10. The role of electronic energy loss in ion beam modification of materials

    DOE PAGESBeta

    Weber, William J.; Duffy, Dorothy M.; Thome, Lionel; Zhang, Yanwen

    2014-10-05

    The interaction of energetic ions with solids results in energy loss to both atomic nuclei and electrons in the solid. In this article, recent advances in understanding and modeling the additive and competitive effects of nuclear and electronic energy loss on the response of materials to ion irradiation are reviewed. Experimental methods and large-scale atomistic simulations are used to study the separate and combined effects of nuclear and electronic energy loss on ion beam modification of materials. The results demonstrate that nuclear and electronic energy loss can lead to additive effects on irradiation damage production in some materials; while inmore » other materials, the competitive effects of electronic energy loss leads to recovery of damage induced by elastic collision cascades. Lastly, these results have significant implications for ion beam modification of materials, non-thermal recovery of ion implantation damage, and the response of materials to extreme radiation environments.« less

  11. The role of electronic energy loss in ion beam modification of materials

    SciTech Connect

    Weber, William J.; Duffy, Dorothy M.; Thome, Lionel; Zhang, Yanwen

    2014-10-05

    The interaction of energetic ions with solids results in energy loss to both atomic nuclei and electrons in the solid. In this article, recent advances in understanding and modeling the additive and competitive effects of nuclear and electronic energy loss on the response of materials to ion irradiation are reviewed. Experimental methods and large-scale atomistic simulations are used to study the separate and combined effects of nuclear and electronic energy loss on ion beam modification of materials. The results demonstrate that nuclear and electronic energy loss can lead to additive effects on irradiation damage production in some materials; while in other materials, the competitive effects of electronic energy loss leads to recovery of damage induced by elastic collision cascades. Lastly, these results have significant implications for ion beam modification of materials, non-thermal recovery of ion implantation damage, and the response of materials to extreme radiation environments.

  12. Design and analysis of a connected broadband multi-piezoelectric-bimorph- beam energy harvester.

    PubMed

    Zhang, Haifeng; Afzalul, Karim

    2014-06-01

    The rapid growth of remote, wireless, and microelectromechanical system (MEMS) devices over the past decades has motivated the development of a self-powered system that can replace traditional electrochemical batteries. Piezoelectric energy harvesters are ideal for capturing energy from mechanical vibrations in the ambient environment. Numerous studies have been made of this application of piezoelectric energy conversion; however, the narrow frequency operation band has limited its application to generate useful power. In this paper, a broadband energy harvester with an array/matrix of piezoelectric bimorphs connected by springs has been designed and analyzed based on the 1-D piezoelectric beam equations. The predicted result shows that the operational frequency band can be enlarged significantly by carefully adjusting the small end masses, length of the beam and spring stiffness. An optimal selection of the load impedance to realize the maximum power output is discussed. The results provide an important foundation for future broadband energy harvester design. PMID:24859665

  13. Design and analysis of a connected broadband multi-piezoelectric-bimorph- beam energy harvester.

    PubMed

    Zhang, Haifeng; Afzalul, Karim

    2014-06-01

    The rapid growth of remote, wireless, and microelectromechanical system (MEMS) devices over the past decades has motivated the development of a self-powered system that can replace traditional electrochemical batteries. Piezoelectric energy harvesters are ideal for capturing energy from mechanical vibrations in the ambient environment. Numerous studies have been made of this application of piezoelectric energy conversion; however, the narrow frequency operation band has limited its application to generate useful power. In this paper, a broadband energy harvester with an array/matrix of piezoelectric bimorphs connected by springs has been designed and analyzed based on the 1-D piezoelectric beam equations. The predicted result shows that the operational frequency band can be enlarged significantly by carefully adjusting the small end masses, length of the beam and spring stiffness. An optimal selection of the load impedance to realize the maximum power output is discussed. The results provide an important foundation for future broadband energy harvester design.

  14. Mitigation of cross-beam energy transfer: Implication of two-state focal zooming on OMEGA

    SciTech Connect

    Froula, D. H.; Kessler, T. J.; Igumenshchev, I. V.; Betti, R.; Goncharov, V. N.; Huang, H.; Hu, S. X.; Hill, E.; Kelly, J. H.; Meyerhofer, D. D.; Shvydky, A.; Zuegel, J. D.

    2013-08-15

    Cross-beam energy transfer (CBET) during OMEGA low-adiabat cryogenic experiments reduces the hydrodynamic efficiency by ∼35%, which lowers the calculated one-dimensional (1-D) yield by a factor of 7. CBET can be mitigated by reducing the diameter of the laser beams relative to the target diameter. Reducing the diameter of the laser beams by 30%, after a sufficient conduction zone has been generated (two-state zooming), is predicted to maintain low-mode uniformity while recovering 90% of the kinetic energy lost to CBET. A radially varying phase plate is proposed to implement two-state zooming on OMEGA. A beam propagating through the central half-diameter of the phase plate will produce a large spot, while a beam propagating through the outer annular region of the phase plate will produce a narrower spot. To generate the required two-state near-field laser-beam profile, a picket driver with smoothing by spectral dispersion (SSD) would pass through an apodizer, forming a beam of half the standard diameter. A second main-pulse driver would co-propagate without SSD through its own apodizer, forming a full-diameter annular beam. Hydrodynamic simulations, using the designed laser spots produced by the proposed zooming scheme on OMEGA, show that implementing zooming will increase the implosion velocity by 25% resulting in a 4.5× increase in the 1-D neutron yield. Demonstrating zooming on OMEGA would validate a viable direct-drive CBET mitigation scheme and help establish a pathway to hydrodynamically equivalent direct-drive–ignition implosions by increasing the ablation pressure (1.6×), which will allow for more stable implosions at ignition-relevant velocities.

  15. Study of Collective Beam Effects in Energy Recovery Linac Driven Free Electron Lasers

    NASA Astrophysics Data System (ADS)

    Hall, Christpher C.

    Collective beam effects such as coherent synchrotron radiation (CSR) and longitudinal space charge (LSC) can degrade the quality of high-energy electron beams used for applications such as free-electron lasers (FELs). The advent of energy recovery linac (ERL)-based FELs brings exciting possibilities for very high-average current FELs that can operate with greater efficiency. However, due to the structure of ERLs, they may be even more susceptible to CSR. It is therefore necessary that these collective beam effects be well understood if future ERL-based designs are to be successful. The Jefferson Laboratory ERL driven IR FEL provides an ideal test-bed for looking at how CSR impacts the electron beam. Due to its novel design we can easily test how CSR's impact on the beam varies as a function of compression within the machine. In this work we will look at measurements of both average energy loss and energy spectrum fragmentation as a function of bunch compression. These results are compared to particle tracking simulations including a 1D CSR model and, in general, good agreement is seen between simulation and measurement. Of particular interest is fragmentation of the energy spectrum that is observed due to CSR and LSC. We will also show how this fragmentation develops and how it can be mitigated through use of the sextupoles in the JLab FEL. Finally, a more complete 2D model is used to simulate CSR-beam interaction. Due to the parameters of the experiment it is expected that a 2D CSR model would yield different results than the 1D CSR model. However, excellent agreement is seen between the two CSR model results.

  16. The wave energy flux of high frequency diffracting beams in complex geometrical optics

    NASA Astrophysics Data System (ADS)

    Maj, Omar; Mariani, Alberto; Poli, Emanuele; Farina, Daniela

    2013-04-01

    We consider the construction of asymptotic solutions of Maxwell's equations for a diffracting wave beam in the high frequency limit and address the description of the wave energy flux transported by the beam. With this aim, the complex eikonal method is applied. That is a generalization of the standard geometrical optics method in which the phase function is assumed to be complex valued, with the non-negative imaginary part accounting for the finite width of the beam cross section. In this framework, we propose an argument which simplifies significantly the analysis of the transport equation for the wave field amplitude and allows us to derive the wave energy flux. The theoretical analysis is illustrated numerically for the case of electron cyclotron beams in tokamak plasmas by using the GRAY code [D. Farina, Fusion Sci. Technol. 52, 154 (2007)], which is based upon the complex eikonal theory. The results are compared to those of the paraxial beam tracing code TORBEAM [E. Poli et al., Comput. Phys. Commun. 136, 90 (2001)], which provides an independent calculation of the energy flow.

  17. Design, Fabrication, and Testing of Composite Energy-Absorbing Keel Beams for General Aviation Type Aircraft

    NASA Technical Reports Server (NTRS)

    Kellas, Sotiris; Knight, Norman F., Jr.

    2002-01-01

    A lightweight energy-absorbing keel-beam concept was developed and retrofitted in a general aviation type aircraft to improve crashworthiness performance. The energy-absorbing beam consisted of a foam-filled cellular structure with glass fiber and hybrid glass/kevlar cell walls. Design, analysis, fabrication and testing of the keel beams prior to installation and subsequent full-scale crash testing of the aircraft are described. Factors such as material and fabrication constraints, damage tolerance, crush stress/strain response, seat-rail loading, and post crush integrity, which influenced the course of the design process are also presented. A theory similar to the one often used for ductile metal box structures was employed with appropriate modifications to estimate the sustained crush loads for the beams. This, analytical tool, coupled with dynamic finite element simulation using MSC.Dytran were the prime design and analysis tools. The validity of the theory as a reliable design tool was examined against test data from static crush tests of beam sections while the overall performance of the energy-absorbing subfloor was assessed through dynamic testing of 24 in long subfloor assemblies.

  18. Generating a Reduced-energy Antiproton beam using Channeling Electrostatic elements (GRACE)

    NASA Astrophysics Data System (ADS)

    Lawler, Gerard; Pacifico, Nicola; Aegis Collaboration

    2016-03-01

    A device was designed for Generating a Reduced-energy Antiproton-beam using Channeling Electrostatic elements (GRACE). A series of einzel lenses and electrodes are used to create a slow beam of antiprotons with tunable mean energy (0 to 16 keV with root mean squared value below 20%) using antiprotons (mean energy of 5 MeV) from the Antiproton Decelerator (AD) at CERN. Degrader foil is in place, so GRACE further deflects the beam bunches away from the annihilation products, focusing them on a 14 mm x 14 mm detector. Manufacturing parameters were found using simulations written in C++. The device is currently in use by the Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy (AEgIS) collaboration at CERN, which seeks to measure the sign of the gravitational constant for antimatter by performing interferometry studies on an antihydrogen beam. GRACE delivers on the order of 10 events per beam bunch from the AD. Antiprotons will eventually be used together with a pulse of positronium atoms to make antihydrogen atoms with horizontal velocity. GRACE is being used to perform intermediary experiments concerning interferometry of antiprotons, an important stepping stone on the way to measuring the sign of gravity. Special thanks to Boston University Undergraduate Research Opportunities Program, Lawrence Sulak, and Michael Doser.

  19. High-energy flat-top beams for laser launching using a Gaussian mirror.

    PubMed

    Fujiwara, Hiroki; Brown, Kathryn E; Dlott, Dana D

    2010-07-01

    Converting a Gaussian to a flat-top beam is useful for many applications including laser-launched thin-foil flyer plates. A flat-top beam is needed to maintain a constant launch velocity across the flyer; otherwise, the flyer can disintegrate in flight. Here we discuss and demonstrate the use of a variable reflectivity mirror (VRM) with a Gaussian reflectivity profile with an additional hard aperture and compare it to a refractive beam shaper. An ideal VRM would generate a flat-top beam with 37% efficiency. Readily available high-power Gaussian or super-Gaussian mirrors create an approximate flat-top profile, but there is a trade-off between flatness and efficiency. We show that a super-Gaussian mirror can, in principle, convert an input Gaussian beam with 30% efficiency to a flat-top beam with 3% (maximum-to-minimum) variation. With a Gaussian mirror and a high-energy pulsed Nd:YAG laser having relatively poor beam quality, we generate flat-top beams with 25% conversion efficiency having 6% variation (standard deviation sigma=4.2%). The beams are used to launch 400 microm diameter, 25 microm thick Al flyer plates, whose flight was monitored by a high-speed displacement interferometer. The plates flew across a 300 microm gap at 1.3 km/s. The distribution of arrival times at the witness plate was 5 ns, as determined by the rise time of the impact emission. Compared to a total flight time of 260 ns, the velocity spread of different parts of the flyer plate was 2%.

  20. Characterization of the high-energy neutron beam of the PRISMA beamline using a diamond detector

    NASA Astrophysics Data System (ADS)

    Cazzaniga, C.; Frost, C. D.; Minniti, T.; Schooneveld, E.; Perelli Cippo, E.; Tardocchi, M.; Rebai, M.; Gorini, G.

    2016-07-01

    The high-energy neutron component (En > 10 MeV) of the neutron spectrum of PRISMA, a beam-line at the ISIS spallation source, has been characterized for the first time. Neutron measurements using a Single-crystal Diamond Detector at a short-pulse source are obtained by a combination of pulse height and time of flight analysis. An XY scan provides a 2D map of the high-energy neutron beam which has a diameter of about 40 mm. The high neutron flux, that has been found to be (3.8 ± 0.7) · 105 cm‑2s‑1 for En > 10 MeV in the centre, opens up for a possible application of the beam-line as a high-energy neutron irradiation position. Results are of interest for the development of the ChipIR beam-line, which will feature an atmospheric-like neutron spectrum for chip irradiation experiment. Furthermore, these results demonstrate that diamond detectors can be used at spallation sources to investigate the transport of high-energy neutrons down instruments which is of interest in general to designers as high-energy neutrons are a source of background in thermal beamlines.

  1. Total Kinetic Energy Of Non-Thermal Electron-Beams In Z-Pinch Experiments

    NASA Astrophysics Data System (ADS)

    Hammel, Ben; McKee, Erik; Wallace, Matt; Presura, Radu; Covington, Aaron; Darling, Tim

    2015-11-01

    An approach to infer the total energy of energetic electron-beams generated in pulsed-power driven pinch experiments is discussed. Using x-pinch wire arrays, we measured the dynamic response of a target anode material as a result of ablative shock loading following the rapid deposition of energy from the incident electron-beam. The time-profile of the drive is obtained through measurement of bremsstrahlung emission with scintillator-PMT diagnostics. MCNP is then used to correlate electron-beam spectrum to the detected hard x-ray signal, and compared with experiments fielding a timer-resolved electron-energy analyzer. Shock strength is inferred by using a line-imaging Velocity Interferometer System for Any Reflector, which recorded the target's free-surface velocity at shock breakout. Lastly, hydrodynamic simulations in HYDRA allow us to infer the total energy of the drive under the boundary conditions of the measured drive profile and shock strength. Information on the total beam-energy provides a better understanding of plasma pinch dynamics that contribute to the observation of non-thermal bremsstrahlung and detection of cold-characteristic x-ray emission from ``hot-spots.'' Support for this work is provided by DOE/NNSA grant DE-NA0002075.

  2. An Overview of Brazilian Developments in Beamed Energy Aerospace Propulsion and Vehicle Performance Control

    NASA Astrophysics Data System (ADS)

    Minucci, M. A. S.

    2008-04-01

    Beamed energy propulsion and beamed energy vehicle performance control concepts are equally promising and challenging. In Brazil, the two concepts are being currently investigated at the Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, of the Institute for Advanced Studies—IEAv, in collaboration with the Rensselaer Polytechnic Institute—RPI, Troy, NY, and the United States Air force Research Laboratory-AFRL. Until recently, only laser energy addition for hypersonic flow control was being investigated at the Laboratory using a 0.3 m nozzle exit diameter hypersonic shock tunnel, T2, and two 7 joule CO2 TEA lasers. Flow visualization, model pressure and heat flux measurements of the laser energy addition perturbed flow around a model were produced as a result of this joint IEAv-RPI investigation. Presently, with the participation of AFRL and the newly commissioned 0.6 m. nozzle exit diameter hypersonic shock tunnel, T3, a more ambitious project is underway. Two 400 Joule Lumonics 620 CO2 TEA lasers will deliver a 20 cm X 25 cm propulsive laser beam to a complete laser propelled air breather/rocket hypersonic engine, located inside T3 test section. Schlieren photographs of the flow inside de engine as well as surface and heat flux measurements will be performed for free stream Mach numbers ranging from 6 to 25. The present paper discusses past, present and future Brazilian activities on beamed energy propulsion and related technologies.

  3. Modeling energy transport in a cantilevered Euler-Bernoulli beam actively vibrating in Newtonian fluid

    NASA Astrophysics Data System (ADS)

    Faria, Cassio T.; Inman, Daniel J.

    2014-04-01

    When a mechanical and/or structural component is immersed in a fluid and it vibrates, the reasonable assumption is that part of the energy is transmitted to the adjacent media. For some engineering applications the energy transport between these two domains, i.e., structure and fluid, plays a central role. The work presented in this paper is focused on discussing the energy transport in beam-like structures as they can be used to represent flexible swimmers (fish-like pulsating mechanisms) in their simplest form. In order to expose the role of each of the fluid and beam properties effecting the energy transfer process, a simplified analytical fluid-structure interaction (FSI) model is derived. After analysis of the resulting coupled-systems' damping coefficient, a new energy transport component is added to the initial Euler-Bernoulli beam equation; a term associated with diffusion (fluid viscosity). In addition our modeling results in an added mass term, a characteristic consistent with previous literature. While deriving the model, an important assumption is made: beam mode shapes are not significantly affected by the domains' interaction. This hypothesis is experimentally tested in two different fluid media and confirmed to be reasonable for the first three vibration mode shapes.

  4. An Overview of Brazilian Developments in Beamed Energy Aerospace Propulsion and Vehicle Performance Control

    SciTech Connect

    Minucci, M. A. S.

    2008-04-28

    Beamed energy propulsion and beamed energy vehicle performance control concepts are equally promising and challenging. In Brazil, the two concepts are being currently investigated at the Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, of the Institute for Advanced Studies--IEAv, in collaboration with the Rensselaer Polytechnic Institute--RPI, Troy, NY, and the United States Air force Research Laboratory-AFRL. Until recently, only laser energy addition for hypersonic flow control was being investigated at the Laboratory using a 0.3 m nozzle exit diameter hypersonic shock tunnel, T2, and two 7 joule CO{sub 2} TEA lasers. Flow visualization, model pressure and heat flux measurements of the laser energy addition perturbed flow around a model were produced as a result of this joint IEAv-RPI investigation. Presently, with the participation of AFRL and the newly commissioned 0.6 m. nozzle exit diameter hypersonic shock tunnel, T3, a more ambitious project is underway. Two 400 Joule Lumonics 620 CO{sub 2} TEA lasers will deliver a 20 cm X 25 cm propulsive laser beam to a complete laser propelled air breather/rocket hypersonic engine, located inside T3 test section. Schlieren photographs of the flow inside de engine as well as surface and heat flux measurements will be performed for free stream Mach numbers ranging from 6 to 25. The present paper discusses past, present and future Brazilian activities on beamed energy propulsion and related technologies.

  5. Characterization of the high-energy neutron beam of the PRISMA beamline using a diamond detector

    NASA Astrophysics Data System (ADS)

    Cazzaniga, C.; Frost, C. D.; Minniti, T.; Schooneveld, E.; Perelli Cippo, E.; Tardocchi, M.; Rebai, M.; Gorini, G.

    2016-07-01

    The high-energy neutron component (En > 10 MeV) of the neutron spectrum of PRISMA, a beam-line at the ISIS spallation source, has been characterized for the first time. Neutron measurements using a Single-crystal Diamond Detector at a short-pulse source are obtained by a combination of pulse height and time of flight analysis. An XY scan provides a 2D map of the high-energy neutron beam which has a diameter of about 40 mm. The high neutron flux, that has been found to be (3.8 ± 0.7) · 105 cm-2s-1 for En > 10 MeV in the centre, opens up for a possible application of the beam-line as a high-energy neutron irradiation position. Results are of interest for the development of the ChipIR beam-line, which will feature an atmospheric-like neutron spectrum for chip irradiation experiment. Furthermore, these results demonstrate that diamond detectors can be used at spallation sources to investigate the transport of high-energy neutrons down instruments which is of interest in general to designers as high-energy neutrons are a source of background in thermal beamlines.

  6. Optical transition radiation used in the diagnostic of low energy and low current electron beams in particle accelerators

    SciTech Connect

    Silva, T. F.; Bonini, A. L.; Lima, R. R.; Maidana, N. L.; Malafronte, A. A.; Pascholati, P. R.; Vanin, V. R.; Martins, M. N.

    2012-09-15

    Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.

  7. Optical transition radiation used in the diagnostic of low energy and low current electron beams in particle accelerators.

    PubMed

    Silva, T F; Bonini, A L; Lima, R R; Maidana, N L; Malafronte, A A; Pascholati, P R; Vanin, V R; Martins, M N

    2012-09-01

    Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.

  8. Quality assurance of electron and photon beam energy using the BQ-CHECK phantom.

    PubMed

    Speight, Richard J; Esmail, Ashraf; Weston, Steve J

    2011-02-01

    The BQ-CHECK phantom (PTW Freiburg, Germany) has been designed to be used with a 2D ion chamber array to facilitate the quality assurance (QA) of electron and photon beam qualities (BQ). The BQ-CHECK phantom has three wedges covering the diagonal axes of the beam: two opposed aluminum wedges used to measure electron energy and a single copper wedge used to measure photon energy. The purpose of this work was to assess the suitability of the BQ-CHECK phantom for use in a routine QA program. A range of percentage depth dose (PDD) curves for two photon beams and four electron beams were measured using a MP3 plotting tank (PTW Freiburg). These beams were used to irradiate a STARCHECK array (PTW Freiburg) with and without the BQ-CHECK phantom on top of the array. For photons, the ratio of the signals from two chambers underneath the copper wedge was used as an effective TPR measurement (TPR(eff)) and, for electrons, the full width at half maximum of the profile (E(FWHM)) underneath the aluminum wedges was used as an electron energy constancy measurement. PDD measurements were compared with TPR(eff) and E(FWHM) to assess the sensitivity of the BQ-CHECK phantom. The clinical tolerances of TPReff were determined for 6 MV (0.634-0.649), and 10MV (0.683-0.692). For electrons, the clinical tolerances of EFWHM were determined for 6 MeV (94.8-103.4 mm), 8 MeV (105.5-114.0 mm), 10 MeV (125.4-133.9 mm) and 12 MeV (138.8-147.3 mm).Electron and photon energy metrics are presented which demonstrate that the BQ-CHECK phantom could be used to form part of an efficient routine monthly QA program. Acceptable beam quality limits for various nominal beam energies were established and at these limits, modified profiles were acquired using the STARCHECK array. From the modified profiles, E(FWHM) and TPR(eff) were determined for the electron and photon beams, respectively. It was demonstrated that both E(FWHM) and the TPR(eff) have a linear relationship with conventional beam quality metrics.

  9. Energy response of glass bead TLDs irradiated with radiation therapy beams

    NASA Astrophysics Data System (ADS)

    Jafari, S. M.; Jordan, T. J.; Hussein, M.; Bradley, D. A.; Clark, C. H.; Nisbet, A.; Spyrou, N. M.

    2014-11-01

    Glass beads are a novel TL dosimeter in radiotherapy. An important characteristic of TL dosimeters is their energy response, especially when intended for use in radiotherapy applications over a wide range of energies (typically from X-rays generated at 80 kVp up to 25 MV photon and MeV electron beams). In this paper, the energy response of glass beads (Mill Hill, Japan) is investigated for their TL response to kV X-rays from an orthovoltage radiotherapy unit and also for MV photon and MeV electron beams from a medical linear accelerator. The experimental findings show that for photon and electron beams, the TL response of this particular glass bead, normalised to unity for 6 MV X-rays (TPR20/10=0.670), decreases to 0.96±0.02 for 15 MV X-rays (TPR20/10=0.761) and to 0.95±0.01 for 20 MeV electron beams (R50,D=8.35 cm). This compares favourably with other TLD materials such as LiF and also alanine dosimeters that are readout with an EPR system. For kV X-rays, the response increases to 4.52±0.05 for 80 kV X-rays (HVL=2.4 mm Al) which approaches 3 times that of LiF TLDs and 5 times that of alanine. In conclusion, the particular glass beads, when used as a dosimeter material, show a relatively small energy dependence over the megavoltage range of clinically relevant radiation qualities, being clearly advantageous for accurate dosimetry. Conversely, the energy response is significant for photon beam energies covering the kV range. In both circumstances, in dosimetric evaluations the energy response needs to be taken into account.

  10. Design of a large acceptance, high efficiency energy selection system for the ELIMAIA beam-line

    NASA Astrophysics Data System (ADS)

    Schillaci, F.; Maggiore, M.; Andó, L.; Cirrone, G. A. P.; Cuttone, G.; Romano, F.; Scuderi, V.; Allegra, L.; Amato, A.; Gallo, G.; Korn, G.; Leanza, R.; Margarone, D.; Milluzzo, G.; Petringa, G.

    2016-08-01

    A magnetic chicane based on four electromagnetic dipoles is going to be realized by INFN-LNS to be used as an Energy Selection System (ESS) for laser driven proton beams up to 300 MeV and C6+ up to 70 MeV/u. The system will provide, as output, ion beams with a contrallable energy spread varying from 5% up to 20% according to the aperture slit size. Moreover, it has a very wide acceptance in order to ensure a very high transmission efficiency and, in principle, it has been designed to be used also as an active energy modulator. This system is the core element of the ELIMED (ELI-Beamlines MEDical and Multidisciplinary applications) beam transport, dosimetry and irradiation line that will be developed by INFN-LNS (It) and installed at the ELI-Beamlines facility in Prague (Cz). ELIMED will be the first user's open transport beam-line where a controlled laser-driven ion beam will be used for multidisciplinary research. The definition of well specified characteristics, both in terms of performance and field quality, of the magnetic chicane is crucial for the system realization, for the accurate study of the beam dynamics and for the proper matching with the Permanent Magnet Quadrupoles (PMQs) used as a collection system already designed. Here, the design of the magnetic chicane is described in details together with the adopted solutions in order to realize a robust system form the magnetic point of view. Moreover, the first preliminary transport simulations are also described showing the good performance of the whole beam line (PMQs+ESS).

  11. Focal plane internal energy flows of singular beams in astigmatically aberrated low numerical aperture systems.

    PubMed

    Bahl, Monika; Senthilkumaran, P

    2014-09-01

    Singular beams have circulating energy components. When such beams are focused by low numerical aperture systems suffering from astigmatic aberration, these circulating energy components get modified. The phase gradient introduced by this type of aberration splits the higher charge vortices. The dependence of the charge, the aberration coefficient, and the size of the aperture on the nature of the splitting process are reported in this paper. The transverse components of the Poynting vector fields that can be derived from the phase gradient vector field distributions are further decomposed into solenoidal and irrotational components using the Helmholtz-Hodge decomposition method. The solenoidal components relate to the orbital angular momentum of the beams, and the irrotational components are useful in the transport of intensity equations for phase retrieval.

  12. Nuclear Astrophysical studies using low-energy RI beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Wakabayashi, Y.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kurihara, Y.; Kubono, S.; Teranishi, T.; He, J. J.; Kwon, Y. K.; Nishimura, S.; Togano, Y.; Iwasa, N.; Niikura, M.; Khiem, L. H.

    2009-05-01

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo, used for various studies covering nuclear-astrophysical topics. An application of the RI beam at CRIB for the astrophysical studies is a new measurement of the proton resonance scattering on 7Be. The measurement was performed up to the excitation energy of 6.8 MeV, ans the excitation function above 3.5 MeV was successfully measured for the first time, providing important information about the reaction rate of 7Be(p,γ)8B, which is the key reaction in the solar 8B neutrino production. A preliminary result of the 7Be+p experiment is presented.

  13. Time-delayed beam splitting with energy separation of x-ray channels

    SciTech Connect

    Stetsko, Yuri P.; Shvyd'ko, Yuri V.; Brian Stephenson, G.

    2013-10-21

    We introduce a time-delayed beam splitting method based on the energy separation of x-ray photon beams. It is implemented and theoretically substantiated on an example of an x-ray optical scheme similar to that of the classical Michelson interferometer. The splitter/mixer uses Bragg-case diffraction from a thin diamond crystal. Another two diamond crystals are used as back-reflectors. Because of energy separation and a minimal number (three) of optical elements, the split-delay line has high efficiency and is simple to operate. Due to the high transparency of diamond crystal, the split-delay line can be used in a beam sharing mode at x-ray free-electron laser facilities.

  14. Description of the performances of a thermo-mechanical energy harvester using bimetallic beams

    NASA Astrophysics Data System (ADS)

    Arnaud, A.; Boughaleb, J.; Monfray, S.; Boeuf, F.; Cugat, O.; Skotnicki, T.

    2016-06-01

    Many recent researches have been focused on the development of thermal energy harvesters using thermo-mechanical or thermo-electrical coupling phenomena associated to a first-order thermodynamic transition. In the case of the bimetallic strip heat engine, the exploitation of the thermo-mechanical instability of bimetallic membranes placed in a thermal gradient enables to convert heat into kinetic energy. This paper is a contribution to the modeling and the comprehension of these heat engines. By restraining the study to the simply-supported bimetallic beams and using a Ritz approximation of the beam shape, this paper aims to give an analytical solution to the first mode of the composite beams and then to evaluate the efficiency of the harvesters exploiting these kinds of instability.

  15. Probing the energy flow in Bessel light beams using atomic photoionization

    NASA Astrophysics Data System (ADS)

    Surzhykov, A.; Seipt, D.; Fritzsche, S.

    2016-09-01

    The growing interest in twisted light beams also requires a better understanding of their complex internal structure. Particular attention is currently being given to the energy circulation in these beams as usually described by the Poynting vector field. In the present study we propose to use the photoionization of alkali-metal atoms as a probe process to measure (and visualize) the energy flow in twisted light fields. Such measurements are possible since the angular distribution of photoelectrons, emitted from a small atomic target, appears sensitive to and is determined by the local direction of the Poynting vector. To illustrate the feasibility of the proposed method, detailed calculations were performed for the ionization of sodium atoms by nondiffractive Bessel beams.

  16. Nonlinear targeted energy transfer of two coupled cantilever beams coupled to a bistable light attachment

    NASA Astrophysics Data System (ADS)

    Mattei, P.-O.; Ponçot, R.; Pachebat, M.; Côte, R.

    2016-07-01

    In order to control the sound radiation by a structure, one aims to control vibration of radiating modes of vibration using "Energy Pumping" also named "Targeted Energy Transfer". This principle is here applied to a simplified model of a double leaf panel. This model is made of two beams coupled by a spring. One of the beams is connected to a nonlinear absorber. This nonlinear absorber is made of a 3D-printed support on which is clamped a buckled thin small beam with a small mass fixed at its centre having two equilibrium positions. The experiments showed that, once attached onto a vibrating system to be controlled, under forced excitation of the primary system, the light bistable oscillator allows a reduction of structural vibration up to 10 dB for significant amplitude and frequency range around the first two vibration modes of the system.

  17. Generation of Equal-Energy Orbital Angular Momentum Beams via Photopatterned Liquid Crystals

    NASA Astrophysics Data System (ADS)

    Chen, Peng; Ge, Shi-Jun; Ma, Ling-Ling; Hu, Wei; Chigrinov, Vladimir; Lu, Yan-Qing

    2016-04-01

    Orbital angular momentum (OAM) has been extensively studied to date and has become topical in the last few years due to its potential for increasing bandwidth in optical communications. The so-called Dammann vortex grating (DVG) can generate a series of equal-energy OAM beams and satisfactorily realize OAM parallel detection, an important challenge in this field. However, previously reported DVGs suffer from polarization sensitivity, low efficiency, or the lack of tunability and mode variety. Here, a design of liquid-crystal DVGs is proposed and demonstrated for the generation of various equal-energy OAM beams. The DVGs, featured by alternative orthogonally planar-aligned regions, are carried out via photopatterning technology. Beam arrays composed of arbitrary OAM modes, as well as two-dimensional ones, are generated in good quality and high efficiency. The liquid-crystal DVGs exhibit merits of excellent polarization independency, electrical switchability, and tunability. This supplies a promising approach towards OAM generation, manipulation, and detection.

  18. Nuclear Astrophysical studies using low-energy RI beams at CRIB

    SciTech Connect

    Yamaguchi, H.; Wakabayashi, Y.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kurihara, Y.; Kubono, S.; Niikura, M.; Teranishi, T.; He, J. J.; Kwon, Y. K.; Nishimura, S.; Togano, Y.; Iwasa, N.; Khiem, L. H.

    2009-05-04

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo, used for various studies covering nuclear-astrophysical topics. An application of the RI beam at CRIB for the astrophysical studies is a new measurement of the proton resonance scattering on {sup 7}Be. The measurement was performed up to the excitation energy of 6.8 MeV, ans the excitation function above 3.5 MeV was successfully measured for the first time, providing important information about the reaction rate of {sup 7}Be(p,{gamma}){sup 8}B, which is the key reaction in the solar {sup 8}B neutrino production. A preliminary result of the {sup 7}Be+p experiment is presented.

  19. Low-energy ionization cooling of ions for beta beam sources

    SciTech Connect

    Neuffer, David; /Fermilab

    2007-10-01

    Rubbia et al.[1] have recently suggested that multiturn passage of a low-energy ion beam (v/c {approx_equal} 0.1) through a low-Z target can be used in the production of ions useable for beta-beam sources and that ionization cooling techniques can increase the circulating beam lifetime and thus enhance that production. Some parameters in their initial discussion are somewhat optimistic, and the conditions for 3-D cooling are not completely developed. In the present paper we reconsider some features of the scenarios and suggest some variations that may be more practical. While 3-D cooling is possible at these energies, mixing of longitudinal motion with both horizontal and vertical motion is necessary to obtain simultaneous cooling in all dimensions; we suggest lattice variations that would be needed. Direct and reverse kinematics are described and explored.

  20. Laboratory degradation of Kapton in a low energy oxygen ion beam

    NASA Technical Reports Server (NTRS)

    Ferguson, D. C.

    1984-01-01

    An atomic oxygen ion beam, accelerated from a tunable microwave resonant cavity, was used at Lewis Research Center to bombard samples of the widely used polyimide Kapton. The Kapton experienced degradation and mass loss at high rates, which may be comparable to those found in Space Shuttle operations if the activation energy supplied by the beam enabled surface reactions with the ambient oxygen. The simulation reproduced the directionality (ram-wake dependence) of the degradation, the change in optical properties of the degraded materials, and the structure seen in scanning electron micrographs of samples returned on the Shuttle Trails with a substituted argon ion beam produced no rapid degradation. Energy Dispersive X-ray Analysis (EDAX) showed significant surface composition changes in all bombarded samples. Mass loss rates and surface composition changes are discussed in terms of the possible oxidation chemistry of the interaction. Finally, the question of how the harmful degradation of materials in low Earth orbit can be minimized is addressed.

  1. Laboratory degradation of Kapton in a low energy oxygen ion beam

    NASA Technical Reports Server (NTRS)

    Ferguson, D. C.

    1983-01-01

    An atomic oxygen ion beam, accelerated from a tunable microwave resonant cavity, was used at Lewis Research Center to bombard samples of the widely used polyimide Kapton. The Kapton experienced degradation and mass loss at high rates, which may be comparable to those found in Space Shuttle operations if the activation energy supplied by the beam enabled surface reactions with the ambient oxygen. The simulation reproduced the directionality (ram-wake dependence) of the degradiation, the change in optical properties of the degraded materials, and the structure seen in scanning electron micrographs of samples returned on the Shuttle Trails with a substituted argon ion beam produced no rapid degradation. Energy Dispersive X-ray Analysis (EDAX) showed significant surface composition changes in all bombarded samples. Mass loss rates and surface composition changes are discussed in terms of the possible oxidation chemistry of the interaction. Finally, the question of how the harmful degradation of materials in low earth orbit can be minimized is addressed.

  2. Enhanced relativistic-electron-beam energy loss in warm dense aluminum.

    PubMed

    Vaisseau, X; Debayle, A; Honrubia, J J; Hulin, S; Morace, A; Nicolaï, Ph; Sawada, H; Vauzour, B; Batani, D; Beg, F N; Davies, J R; Fedosejevs, R; Gray, R J; Kemp, G E; Kerr, S; Li, K; Link, A; McKenna, P; McLean, H S; Mo, M; Patel, P K; Park, J; Peebles, J; Rhee, Y J; Sorokovikova, A; Tikhonchuk, V T; Volpe, L; Wei, M; Santos, J J

    2015-03-01

    Energy loss in the transport of a beam of relativistic electrons in warm dense aluminum is measured in the regime of ultrahigh electron beam current density over 2×10^{11}  A/cm^{2} (time averaged). The samples are heated by shock compression. Comparing to undriven cold solid targets, the roles of the different initial resistivity and of the transient resistivity (upon target heating during electron transport) are directly observable in the experimental data, and are reproduced by a comprehensive set of simulations describing the hydrodynamics of the shock compression and electron beam generation and transport. We measured a 19% increase in electron resistive energy loss in warm dense compared to cold solid samples of identical areal mass. PMID:25793822

  3. Enhanced relativistic-electron-beam energy loss in warm dense aluminum.

    PubMed

    Vaisseau, X; Debayle, A; Honrubia, J J; Hulin, S; Morace, A; Nicolaï, Ph; Sawada, H; Vauzour, B; Batani, D; Beg, F N; Davies, J R; Fedosejevs, R; Gray, R J; Kemp, G E; Kerr, S; Li, K; Link, A; McKenna, P; McLean, H S; Mo, M; Patel, P K; Park, J; Peebles, J; Rhee, Y J; Sorokovikova, A; Tikhonchuk, V T; Volpe, L; Wei, M; Santos, J J

    2015-03-01

    Energy loss in the transport of a beam of relativistic electrons in warm dense aluminum is measured in the regime of ultrahigh electron beam current density over 2×10^{11}  A/cm^{2} (time averaged). The samples are heated by shock compression. Comparing to undriven cold solid targets, the roles of the different initial resistivity and of the transient resistivity (upon target heating during electron transport) are directly observable in the experimental data, and are reproduced by a comprehensive set of simulations describing the hydrodynamics of the shock compression and electron beam generation and transport. We measured a 19% increase in electron resistive energy loss in warm dense compared to cold solid samples of identical areal mass.

  4. Surface diffusion activation energy determination using ion beam microtexturing

    NASA Technical Reports Server (NTRS)

    Rossnagel, S. M.; Robinson, R. S.

    1982-01-01

    The activation energy for impurity atom (adatom) surface diffusion can be determined from the temperature dependence of the spacing of sputter cones. These cones are formed on the surface during sputtering while simultaneously adding impurities. The impurities form clusters by means of surface diffusion, and these clusters in turn initiate cone formation. Values are given for the surface diffusion activation energies for various materials on polycrystalline Cu, Al, Pb, Au, and Ni. The values for different impurity species on each of these substrates are approximately independent of impurity species within the experimental uncertainty, suggesting the absence of strong chemical bonding effects on the diffusion.

  5. The design and initial testing of a beam phase and energy measurement for LEDA

    SciTech Connect

    Power, J.; Stettler, M.

    1998-12-10

    A diagnostic system being designed to measure the beam phase and beam energy of the Low Energy Demonstration Accelerator (LEDA) is described and the characterization of the prototype presented. The accelerator, being built at LANL, is a 350 MHz proton linac with a 100 mA beam. In the first beam experiments, the 6.7 MeV RFQ will be characterized. Signals received from an rf cavity probe in the RFQ and capacitive pick-ups along the high-energy beam transport line will be compared in phase in order to calculate the beam phase and energy. The 350 MHz signals from four pick-ups will be converted to 2 MHz in a VXI-based down converter module. A second VXI phase processor module makes two, differential-phase measurements based on its four 2 MHz inputs. The heart of this system is the phase processor module. The phase processor consists of an analog front end (AFE), digital front end (DFE), digital signal processing (DSP) modules and the VXI bus interface. The AFE has an AGC circuit with a >60 dB dynamic range with a few degrees of phase shift. Following the AFE is the DFE which uses an in-phase and quadrature-phase (I and Q) technique to make the phase measurement. The DSP is used to correct the real-time data for phase variations as a function of dynamic range and system offsets. The prototype phase module gives an absolute accuracy of {+-}0.5 degrees with a resolution of <0.1 degrees and a bandwidth of 200 kHz.

  6. The design and initial testing of a beam phase and energy measurement for LEDA

    SciTech Connect

    Power, J.; Stettler, M.

    1998-12-01

    A diagnostic system being designed to measure the beam phase and beam energy of the Low Energy Demonstration Accelerator (LEDA) is described and the characterization of the prototype presented. The accelerator, being built at LANL, is a 350 MHz proton linac with a 100 mA beam. In the first beam experiments, the 6.7 MeV RFQ will be characterized. Signals received from an rf cavity probe in the RFQ and capacitive pick-ups along the high-energy beam transport line will be compared in phase in order to calculate the beam phase and energy. The 350 MHz signals from four pick-ups will be converted to 2 MHz in a VXI-based down converter module. A second VXI phase processor module makes two, differential-phase measurements based on its four 2 MHz inputs. The heart of this system is the phase processor module. The phase processor consists of an analog front end (AFE), digital front end (DFE), digital signal processing (DSP) modules and the VXI bus interface. The AFE has an AGC circuit with a {gt}60 dB dynamic range with a few degrees of phase shift. Following the AFE is the DFE which uses an in-phase and quadrature-phase (I and Q) technique to make the phase measurement. The DSP is used to correct the real-time data for phase variations as a function of dynamic range and system offsets. The prototype phase module gives an absolute accuracy of {plus_minus}0.5 degrees with a resolution of {lt}0.1 degrees and a bandwidth of 200 kHz. {copyright} {ital 1998 American Institute of Physics.}

  7. Generating Polarized High-Brightness Muon Beams With High-Energy Gammas

    SciTech Connect

    Yakimenko, Vitaly

    2009-01-22

    Hadron colliders are impractical at very high energies as effective interaction energy is a fraction of the energies of the beams and luminosity must rise as energy squared. Further, the prevailing gluon-gluon background radiation makes it difficult to sort out events. e{sup +}e{sup -} colliders, on other hand, are constrained at TeV energies by beamstrahlung radiation and also by cost as long linacs are required to avoid synchrotron radiation in the rings. A muon collider will have the same advantages in energy reach as an e{sup +}e{sup -} collider, but without prohibitive beamstrahlung- and synchrotron- radiation. Generation of the high-brightness polarized muon ({mu}{sup -}{mu}{sup +}) beams through gamma conversion into pairs in the nuclei field is considered in this paper. The dominant effect in the interaction of the high-energy photons with the solid target will be the production of electron-positron pairs. The low-phase space of the resulting muon beams adequately compensates for the small probability of generating a {mu}{sup -}{mu}{sup +} pair.

  8. Modeling silicon diode energy response factors for use in therapeutic photon beams.

    PubMed

    Eklund, Karin; Ahnesjö, Anders

    2009-10-21

    Silicon diodes have good spatial resolution, which makes them advantageous over ionization chambers for dosimetry in fields with high dose gradients. However, silicon diodes overrespond to low-energy photons, that are more abundant in scatter which increase with large fields and larger depths. We present a cavity-theory-based model for a general response function for silicon detectors at arbitrary positions within photon fields. The model uses photon and electron spectra calculated from fluence pencil kernels. The incident photons are treated according to their energy through a bipartition of the primary beam photon spectrum into low- and high-energy components. Primary electrons from the high-energy component are treated according to Spencer-Attix cavity theory. Low-energy primary photons together with all scattered photons are treated according to large cavity theory supplemented with an energy-dependent factor K(E) to compensate for energy variations in the electron equilibrium. The depth variation of the response for an unshielded silicon detector has been calculated for 5 x 5 cm(2), 10 x 10 cm(2) and 20 x 20 cm(2) fields in 6 and 15 MV beams and compared with measurements showing that our model calculates response factors with deviations less than 0.6%. An alternative method is also proposed, where we show that one can use a correlation with the scatter factor to determine the detector response of silicon diodes with an error of less than 3% in 6 MV and 15 MV photon beams.

  9. An Energy-Stabilized Varied-Line-Space-Monochromator UndulatorBeam Line for PEEM Illumination and Magnetic Circular Dichroism

    SciTech Connect

    Warwick, Tony; McKinney, Wayne; Domning, Ed; Doran, Andrew; Padmore, Howard

    2006-06-01

    A new undulator beam line has been built and commissioned at the Advanced Light Source for illumination of the PEEM3 microscope. The beam line delivers high flux beams over an energy range from C1s through the transition metals to include the M edges of the magnetic rare earth elements. We present details of the optical design, and data on the performance of the zero-order tracking of the photon energy.

  10. Generating High-Brightness Light Ion Beams for Inertial Fusion Energy

    SciTech Connect

    Adams, R.G.; Bailey, J.E.; Cuneno, M.E.; Desjarlais, M.P.; Filuk, A.B.; Hanson, D.L.; Johnson, D.J.; Mehlohorn, T.A.; Menge, P.R.; Olson, C.L.; Pointon, T.D. Slutz, S.A.; Vesey, R.A.; Welch, D.R.; Wenger, D.F.

    1998-10-22

    Light ion beams may be the best option for an Inertial Fusion Energy (IFE) driver from the standpoint of ei%ciency, standoff, rep-rate operation and cost. This approach uses high-energy-density pulsed power to efficiently accelerate ions in one or two stages at fields of 0.5 to 1.0 GV/m to produce a medium energy (30 MeV), high-current (1 MA) beam of light ions, such as lithium. Ion beams provide the ability for medium distance transport (4 m) of the ions to the target, and standofl of the driver from high- yield implosions. Rep-rate operation of' high current ion sources has ako been demonstrated for industrial applications and couId be applied to IFE. Although (hese factors make light ions the best Iong-teml pulsed- power approach to IFE, light-ion research is being suspended this year in favor of a Z-pinch-driven approach which has the best opport lnity to most-rapidly achieve the U.S. Department of Energy sponsor's goal of high-yield fusion. This paper will summarize the status and most recent results of the light-ion beam program at Sandia National Laboratories (SNL), and document the prospects of light ions for future IFE driver development.

  11. High Energy Accelerator and Colliding Beam User Group: Progress report, March 1, 1988--February 28, 1989

    SciTech Connect

    Not Available

    1988-09-01

    This report discusses work carried out by the High Energy Accelerator and Colliding Beam User Group at the University of Maryland. Particular topics discussed are: OPAL experiment at LEP; deep inelastic muon interactions; B physics with the CLEO detector at CESR; further results from JADE; and search for ''small'' violation of the Pauli principle. (LSP)

  12. AREAL low energy electron beam applications in life and materials sciences

    NASA Astrophysics Data System (ADS)

    Tsakanov, V. M.; Aroutiounian, R. M.; Amatuni, G. A.; Aloyan, L. R.; Aslanyan, L. G.; Avagyan, V. Sh.; Babayan, N. S.; Buniatyan, V. V.; Dalyan, Y. B.; Davtyan, H. D.; Derdzyan, M. V.; Grigoryan, B. A.; Grigoryan, N. E.; Hakobyan, L. S.; Haroutyunian, S. G.; Harutiunyan, V. V.; Hovhannesyan, K. L.; Khachatryan, V. G.; Martirosyan, N. W.; Melikyan, G. S.; Petrosyan, A. G.; Petrosyan, V. H.; Sahakyan, A. A.; Sahakyan, V. V.; Sargsyan, A. A.; Simonyan, A. S.; Tatikyan, S. Sh.; Tsakanova, G. V.; Tsovyan, E.; Vardanyan, A. S.; Vardanyan, V. V.; Yeremyan, A. S.; Yeritsyan, H. N.; Zanyan, G. S.

    2016-09-01

    The AREAL laser-driven RF gun provides 2-5 MeV energy ultrashort electron pulses for experimental study in life and materials sciences. We report the first experimental results of the AREAL beam application in the study of molecular-genetic effects, silicon-dielectric structures, ferroelectric nanofilms, and single crystals for scintillators.

  13. Response investigations of a TEPC in high energy proton and neutron beams using the variance method.

    PubMed

    Kyllönen, J E; Grindborg, J E; Lindborg, L

    2002-01-01

    Results from measurements in proton and neutron beams between 68 and 174 MeV at the T. Svedberg Laboratory in Uppsala are presented. The result indicate that a TEPC might underestimate the high-energy contribution to H*(10) in cosmic radiation applications such as measurements onboard aircraft.

  14. Development of microwave ion source and low energy beam transport system for high current cyclotron

    NASA Astrophysics Data System (ADS)

    Pandit, V. S.; Sing Babu, P.; Goswami, A.; Srivastava, S.; Misra, A.; Chatterjee, Mou; Nabhiraj, P. Y.; Yadav, R. C.; Bhattacharya, S.; Roy, S.; Nandi, C.; Pal, G.; Thakur, S. K.

    2013-12-01

    A 2.45 GHz microwave ion source and a low energy beam transport system have been developed to study the high intensity proton beam injection into a 10 MeV, 5 mA compact cyclotron. We have extracted proton beam more than 10 mA at 80 kV as measured by the DCCT after the extraction and a well collimated beam of 7 mA (through 1 cm × 1 cm slit) at the faraday cup 1.5 m away from the source. The transport of protons from the ion source in the presence of H2+, H3+ species has been studied using PIC simulations through our transport line which consists of two solenoids. We have also installed a small dipole magnet with similar field as that of the cyclotron along with vacuum chamber, spiral inflector and few diagnostic elements at the end of the beam line. In the preliminary testing of inflection, we achieved 1 mA beam on the faraday cup at the exit of inflector with ∼60% transmission efficiency.

  15. Detecting cavitation in mercury exposed to a high-energy pulsed proton beam

    SciTech Connect

    Manzi, Nicholas J; Chitnis, Parag V; Holt, Ray G; Roy, Ronald A; Cleveland, Robin O; Riemer, Bernie; Wendel, Mark W

    2010-01-01

    The Oak Ridge National Laboratory Spallation Neutron Source employs a high-energy pulsed proton beam incident on a mercury target to generate short bursts of neutrons. Absorption of the proton beam produces rapid heating of the mercury, resulting in the formation of acoustic shock waves and the nucleation of cavitation bubbles. The subsequent collapse of these cavitation bubbles promote erosion of the steel target walls. Preliminary measurements using two passive cavitation detectors (megahertz-frequency focused and unfocused piezoelectric transducers) installed in a mercury test target to monitor cavitation generated by proton beams with charges ranging from 0.041 to 4.1 C will be reported on. Cavitation was initially detected for a beam charge of 0.082 C by the presence of an acoustic emission approximately 250 s after arrival of the incident proton beam. This emission was consistent with an inertial cavitation collapse of a bubble with an estimated maximum bubble radius of 0.19 mm, based on collapse time. The peak pressure in the mercury for the initiation of cavitation was predicted to be 0.6 MPa. For a beam charge of 0.41 C and higher, the lifetimes of the bubbles exceeded the reverberation time of the chamber (~300 s), and distinct windows of cavitation activity were detected, a phenomenon that likely resulted from the interaction of the reverberation in the chamber and the cavitation bubbles.

  16. Synchronous timing of multi-energy fast beam extraction during a single AGS cycle

    SciTech Connect

    Gabusi, J.; Naase, S.

    1985-01-01

    Synchronous triggering of fast beams is required because the field of Kicker Magnets must rise within the open space between one beam bunch and the next. Within the Brookhaven AGS, Fast Extracted Beam (FEB) triggering combines nominal timing, based on beam energy with bunch-to-bunch synchronization, based on the accelerating rf waveform. During beam acceleration, a single bunch is extracted at 22 GeV/c and within the same AGS cycle, the remaining eleven bunches are extracted at 28.4 GeV/c. When the single bunch is extracted, a ''hole'', which is left in the remaining circulating beam, can appear in random locations within the second extraction during successive AGS cycles. To overcome this problem, a synchronous rf/12 counting scheme and logic circuitry are used to keep track of the bunch positions relative to each other, and to place the ''hole'' in any desired location within the second extraction. The rf/12 signal is used also to synchronize experimenters triggers.

  17. Gafchromic EBT3 film dosimetry in electron beams - energy dependence and improved film read-out.

    PubMed

    Sipilä, Petri; Ojala, Jarkko; Kaijaluoto, Sampsa; Jokelainen, Ilkka; Kosunen, Antti

    2016-01-01

    For megavoltage photon radiation, the fundamental dosimetry characteristics of Gafchromic EBT3 film were determined in 60Co gamma ray beam with addition of experimental and Monte Carlo (MC)-simulated energy dependence of the film for 6 MV photon beam and 6 MeV, 9 MeV, 12 MeV, and 16 MeV electron beams in water phantom. For the film read-out, two phase correction of scanner sensitivity was applied: a matrix correction for scanning area and dose-dependent correction by iterative procedure. With these corrections, the uniformity of response can be improved to be within ± 50 pixel values (PVs). To improve the read-out accuracy, a procedure with flipped film orientations was established. With the method, scanner uniformity can be improved further and dust particles, scratches and/or dirt on scan-ner glass can be detected and eliminated. Responses from red and green channels were averaged for read-out, which decreased the effect of noise present in values from separate channels. Since the signal level with the blue channel is considerably lower than with other channels, the signal variation due to different perturbation effects increases the noise level so that the blue channel is not recommended to be used for dose determination. However, the blue channel can be used for the detection of emulsion thickness variations for film quality evaluations with unexposed films. With electron beams ranging from 6 MeV to 16 MeV and at reference measurement conditions in water, the energy dependence of the EBT3 film is uniform within 0.5%, with uncertainties close to 1.6% (k = 2). Including 6 MV photon beam and the electron beams mentioned, the energy dependence is within 1.1%. No notable differences were found between the experimental and MC-simulated responses, indicating negligible change in intrinsic energy dependence of the EBT3 film for 6 MV photon beam and 6 MeV-16 MeV electron beams. Based on the dosimetric characteristics of the EBT3 film, the read-out procedure established

  18. Monte Carlo simulation of MOSFET detectors for high-energy photon beams using the PENELOPE code

    NASA Astrophysics Data System (ADS)

    Panettieri, Vanessa; Amor Duch, Maria; Jornet, Núria; Ginjaume, Mercè; Carrasco, Pablo; Badal, Andreu; Ortega, Xavier; Ribas, Montserrat

    2007-01-01

    The aim of this work was the Monte Carlo (MC) simulation of the response of commercially available dosimeters based on metal oxide semiconductor field effect transistors (MOSFETs) for radiotherapeutic photon beams using the PENELOPE code. The studied Thomson&Nielsen TN-502-RD MOSFETs have a very small sensitive area of 0.04 mm2 and a thickness of 0.5 µm which is placed on a flat kapton base and covered by a rounded layer of black epoxy resin. The influence of different metallic and Plastic water™ build-up caps, together with the orientation of the detector have been investigated for the specific application of MOSFET detectors for entrance in vivo dosimetry. Additionally, the energy dependence of MOSFET detectors for different high-energy photon beams (with energy >1.25 MeV) has been calculated. Calculations were carried out for simulated 6 MV and 18 MV x-ray beams generated by a Varian Clinac 1800 linear accelerator, a Co-60 photon beam from a Theratron 780 unit, and monoenergetic photon beams ranging from 2 MeV to 10 MeV. The results of the validation of the simulated photon beams show that the average difference between MC results and reference data is negligible, within 0.3%. MC simulated results of the effect of the build-up caps on the MOSFET response are in good agreement with experimental measurements, within the uncertainties. In particular, for the 18 MV photon beam the response of the detectors under a tungsten cap is 48% higher than for a 2 cm Plastic water™ cap and approximately 26% higher when a brass cap is used. This effect is demonstrated to be caused by positron production in the build-up caps of higher atomic number. This work also shows that the MOSFET detectors produce a higher signal when their rounded side is facing the beam (up to 6%) and that there is a significant variation (up to 50%) in the response of the MOSFET for photon energies in the studied energy range. All the results have shown that the PENELOPE code system can

  19. Electrical and optoelectrical modification of cadmium sulfide nanobelts by low-energy electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Zhang, Lijie; Liu, Manman; Zhao, Mei; Dong, Youqing; Zou, Chao; Yang, Keqin; Yang, Yun; Huang, Shaoming; Zhu, Da-Ming

    2016-09-01

    In this report, we describe a method for modifying electrical and optoelectrical properties of CdS nanobelts using low-energy (lower than 10 keV) e-beam irradiation in a scanning electron microscope. The electrical conductivity of the nanobelts was dramatically improved via the irradiation of e-beams. The modified conductivity of the nanobelts depends on the energy of the e-beam; it exhibits a larger photocurrent and higher external quantum efficiency but slower time-response than that before the modification. A possible mechanism about the modification is the increase of electron accumulation (injected electrons) in the nanobelts due to e-beam irradiation. In addition, the optoelectrical modification could be caused by the trapped electrons in the nanobelts and the decrease of contact resistance between the nanobelts and metal electrodes induced by e-beam irradiation. The results of this work are significant for the in situ study of semiconductor nanostructures in the electron microscope. Besides, the method of electrical and optoelectrical modification presented here has potential application in electronics and optoelectronics.

  20. The effect of electron beams on cyclotron maser emission excited by lower-energy cutoffs

    NASA Astrophysics Data System (ADS)

    Zhao, G. Q.; Feng, H. Q.; Wu, D. J.

    2016-05-01

    Electron-cyclotron maser (ECM) is one of the most important emission mechanisms in astrophysics and can be excited efficiently by lower-energy cutoffs of power-law electrons. These non-thermal electrons probably propagate as a directed collimated beam along ambient magnetic fields. This paper investigates the ECM, in which the effect of electron beams is emphasized. Results show the dependence of emission properties of the ECM on the beam feature. The maximum growth rate of the extraordinary mode (X2) rapidly decreases as the beam momentum increases, while the growth rate of the ordinary mode (O1) changes slightly. In particular, the ordinary mode can overcome the extraordinary mode and becomes the fastest growth mode once the beam momentum is large enough. This research presents an extension of the conventional studies on ECM driven by lower-energy cutoffs and may be helpful to understand better the emission process of solar type I radio bursts, which are dominated by the ordinary mode emission.

  1. Electrical and optoelectrical modification of cadmium sulfide nanobelts by low-energy electron beam irradiation.

    PubMed

    Zhang, Lijie; Liu, Manman; Zhao, Mei; Dong, Youqing; Zou, Chao; Yang, Keqin; Yang, Yun; Huang, Shaoming; Zhu, Da-Ming

    2016-09-30

    In this report, we describe a method for modifying electrical and optoelectrical properties of CdS nanobelts using low-energy (lower than 10 keV) e-beam irradiation in a scanning electron microscope. The electrical conductivity of the nanobelts was dramatically improved via the irradiation of e-beams. The modified conductivity of the nanobelts depends on the energy of the e-beam; it exhibits a larger photocurrent and higher external quantum efficiency but slower time-response than that before the modification. A possible mechanism about the modification is the increase of electron accumulation (injected electrons) in the nanobelts due to e-beam irradiation. In addition, the optoelectrical modification could be caused by the trapped electrons in the nanobelts and the decrease of contact resistance between the nanobelts and metal electrodes induced by e-beam irradiation. The results of this work are significant for the in situ study of semiconductor nanostructures in the electron microscope. Besides, the method of electrical and optoelectrical modification presented here has potential application in electronics and optoelectronics. PMID:27561004

  2. Accelerated Nuclear Energy Materials Development with Multiple Ion Beams

    SciTech Connect

    Fluss, M J; Bench, G

    2009-08-19

    A fundamental issue in nuclear energy is the changes in material properties as a consequence of time, temperature, and neutron fluence. Usually, candidate materials for nuclear energy applications are tested in nuclear reactors to understand and model the changes that arise from a combination of atomic displacements, helium and hydrogen production, and other nuclear transmutations (e.g. fission and the production of fission products). Experiments may be carried out under neutron irradiation conditions in existing nuclear materials test reactors (at rates of 10 to 20 displacements per atom (DPA) per year or burn-up rates of a few percent per year for fertile fuels), but such an approach takes much too long for many high neutron fluence scenarios (300 DPA for example) expected in reactors of the next generation. Indeed it is reasonable to say that there are no neutron sources available today to accomplish sufficiently rapid accelerated aging let alone also provide the temperature and spectral characteristics of future fast spectrum nuclear energy systems (fusion and fission both). Consequently, materials research and development progress continues to be severely limited by this bottleneck.

  3. Auroral electron beams - Electric currents and energy sources

    NASA Astrophysics Data System (ADS)

    Kaufmann, R. L.

    1981-09-01

    The energy sources, electric equipotentials and electric currents associated with auroral electron acceleration observed during rocket flight 18:152 are discussed. Steep flow gradients at the interface between the convection boundary layer and the plasma sheet are considered as the probable source of energy for dayside and dawn and dusk auroras, while it is suggested that the cross tail potential drop may provide an energy source for some midnight auroras. Birkeland currents that flow along distorted field lines are shown possibly to be important in the mechanism that produces U-shaped equipotentials in the ionosphere, as well as unexpected jumps in ionospheric or magnetotail currents and unusual electric fields and plasma drift in the magnetotail. The production of equipotential structures under oppositely directed higher-altitude electric fields is discussed, and it is pointed out that cold ionospheric plasma can enter the structure in a cusp-shaped region where fields are weak. The rocket data reveals that the sudden change in conductivity at the edge of the bright arc and the constancy of the electric field produce sudden changes in the Hall and Pedersen currents. It is concluded that current continuity is satisfied primarily by east-west changes in the electric field or conductivity.

  4. Electrostatic energy analyzer measurements of low energy zirconium beam parameters in a plasma sputter-type negative ion source.

    PubMed

    Malapit, Giovanni M; Mahinay, Christian Lorenz S; Poral, Matthew D; Ramos, Henry J

    2012-02-01

    A plasma sputter-type negative ion source is utilized to produce and detect negative Zr ions with energies between 150 and 450 eV via a retarding potential-type electrostatic energy analyzer. Traditional and modified semi-cylindrical Faraday cups (FC) inside the analyzer are employed to sample negative Zr ions and measure corresponding ion currents. The traditional FC registered indistinct ion current readings which are attributed to backscattering of ions and secondary electron emissions. The modified Faraday cup with biased repeller guard ring, cut out these signal distortions leaving only ringings as issues which are theoretically compensated by fitting a sigmoidal function into the data. The mean energy and energy spread are calculated using the ion current versus retarding potential data while the beam width values are determined from the data of the transverse measurement of ion current. The most energetic negative Zr ions yield tighter energy spread at 4.11 eV compared to the least energetic negative Zr ions at 4.79 eV. The smallest calculated beam width is 1.04 cm for the negative Zr ions with the highest mean energy indicating a more focused beam in contrast to the less energetic negative Zr ions due to space charge forces.

  5. Electrostatic energy analyzer measurements of low energy zirconium beam parameters in a plasma sputter-type negative ion source

    SciTech Connect

    Malapit, Giovanni M.; Mahinay, Christian Lorenz S.; Poral, Matthew D.; Ramos, Henry J.

    2012-02-15

    A plasma sputter-type negative ion source is utilized to produce and detect negative Zr ions with energies between 150 and 450 eV via a retarding potential-type electrostatic energy analyzer. Traditional and modified semi-cylindrical Faraday cups (FC) inside the analyzer are employed to sample negative Zr ions and measure corresponding ion currents. The traditional FC registered indistinct ion current readings which are attributed to backscattering of ions and secondary electron emissions. The modified Faraday cup with biased repeller guard ring, cut out these signal distortions leaving only ringings as issues which are theoretically compensated by fitting a sigmoidal function into the data. The mean energy and energy spread are calculated using the ion current versus retarding potential data while the beam width values are determined from the data of the transverse measurement of ion current. The most energetic negative Zr ions yield tighter energy spread at 4.11 eV compared to the least energetic negative Zr ions at 4.79 eV. The smallest calculated beam width is 1.04 cm for the negative Zr ions with the highest mean energy indicating a more focused beam in contrast to the less energetic negative Zr ions due to space charge forces.

  6. Internal electric energy in a spherical particle illuminated with a plane wave or off-axis Gaussian beam.

    PubMed

    Khaled, E E; Hill, S C; Barber, P W

    1994-01-20

    The electric energy in a lossless or lossy spherical particle that is illuminated with a plane wave or a Gaussian beam is investigated. The analysis uses a combination of the plane-wave spectrum technique and the T-matrix method. Expressions for the electric energy in any mode as well as the total electric energy inside the particle are given. The amount of energy coupling into the particle for different beam illuminations is also investigated. The high-Q (low-order) resonant modes can dominate the electric energy inside a spherical particle many linewidths away from the resonance location, particularly if the beam is focused at the droplet edge or outside the droplet. If the sphere is lossy, low-order modes can still dominate the electric energy if the beam is focused far enough outside the sphere. As the absorption coefficient of the particle increases, the energy in a high-Q mode decreases much faster at the resonance frequency than it does at near or off-resonance frequencies. The effects of the absorption on the dominance of the internal fields by a high-Q mode decreases as the beam is shifted farther away from the particle. As the beam is shifted farther away from the particle the fraction of the incident energy coupled into the sphere at resonance first increases and then decreases. Although the coupled energy decreases as the beam is shifted farther from the sphere, most of that energy is in the lowest-order mode.

  7. Modeling of the cross-beam energy transfer with realistic inertial-confinement-fusion beams in a large-scale hydrocode.

    PubMed

    Colaïtis, A; Duchateau, G; Ribeyre, X; Tikhonchuk, V

    2015-01-01

    A method for modeling realistic laser beams smoothed by kinoform phase plates is presented. The ray-based paraxial complex geometrical optics (PCGO) model with Gaussian thick rays allows one to create intensity variations, or pseudospeckles, that reproduce the beam envelope, contrast, and high-intensity statistics predicted by paraxial laser propagation codes. A steady-state cross-beam energy-transfer (CBET) model is implemented in a large-scale radiative hydrocode based on the PCGO model. It is used in conjunction with the realistic beam modeling technique to study the effects of CBET between coplanar laser beams on the target implosion. The pseudospeckle pattern imposed by PCGO produces modulations in the irradiation field and the shell implosion pressure. Cross-beam energy transfer between beams at 20(∘) and 40(∘) significantly degrades the irradiation symmetry by amplifying low-frequency modes and reducing the laser-capsule coupling efficiency, ultimately leading to large modulations of the shell areal density and lower convergence ratios. These results highlight the role of laser-plasma interaction and its influence on the implosion dynamics.

  8. Modeling of the cross-beam energy transfer with realistic inertial-confinement-fusion beams in a large-scale hydrocode.

    PubMed

    Colaïtis, A; Duchateau, G; Ribeyre, X; Tikhonchuk, V

    2015-01-01

    A method for modeling realistic laser beams smoothed by kinoform phase plates is presented. The ray-based paraxial complex geometrical optics (PCGO) model with Gaussian thick rays allows one to create intensity variations, or pseudospeckles, that reproduce the beam envelope, contrast, and high-intensity statistics predicted by paraxial laser propagation codes. A steady-state cross-beam energy-transfer (CBET) model is implemented in a large-scale radiative hydrocode based on the PCGO model. It is used in conjunction with the realistic beam modeling technique to study the effects of CBET between coplanar laser beams on the target implosion. The pseudospeckle pattern imposed by PCGO produces modulations in the irradiation field and the shell implosion pressure. Cross-beam energy transfer between beams at 20(∘) and 40(∘) significantly degrades the irradiation symmetry by amplifying low-frequency modes and reducing the laser-capsule coupling efficiency, ultimately leading to large modulations of the shell areal density and lower convergence ratios. These results highlight the role of laser-plasma interaction and its influence on the implosion dynamics. PMID:25679718

  9. Plasma effects on extragalactic ultra-high-energy cosmic ray hadron beams in cosmic voids

    SciTech Connect

    Krakau, S.; Schlickeiser, R. E-mail: rsch@tp4.rub.de

    2014-07-01

    The linear instability of an ultrarelativistic hadron beam (Γ {sub b} ≈ 10{sup 6}) in the unmagnetized intergalactic medium (IGM) is investigated with respect to the excitation of collective electrostatic and aperiodic electromagnetic fluctuations. This analysis is important for the propagation of extragalactic ultrarelativistic cosmic rays (E > 10{sup 15} eV) from their distant sources to Earth. We calculate minimum instability growth times that are orders of magnitude shorter than the cosmic ray propagation time in the IGM. Due to nonlinear effects, especially the modulation instability, the cosmic ray beam stabilizes and can propagate with nearly no energy loss through the IGM.

  10. Manipulating a neutrino spectrum to maximize the physics potential from a low-energy {beta} beam

    SciTech Connect

    Amanik, Philip S.; McLaughlin, Gail C.

    2007-06-15

    Proposed low-energy {beta}-beam facilities would be capable of producing intense beams of neutrinos (antineutrinos) with well-defined spectra. We present analytic expressions and numerical results that accurately show how the total neutrino flux reaching the detector depends on the geometry of the source and the detector. Several authors have proposed measurements which require using different flux shapes. We show that detectors of different sizes and shapes will receive neutrino fluxes with different spectral shapes and that the spectral shape will also be different in different regions of the same detector. Our findings also show that for certain measurements, systematic uncertainties and run time can be reduced.

  11. Short-pulse, high-energy radiation generation from laser-wakefield accelerated electron beams

    NASA Astrophysics Data System (ADS)

    Schumaker, Will

    2013-10-01

    Recent experimental results of laser wakefield acceleration (LWFA) of ~GeV electrons driven by the 200TW HERCULES and the 400TW ASTRA-GEMINI laser systems and their subsequent generation of photons, positrons, and neutrons are presented. In LWFA, high-intensity (I >1019 W /cm2), ultra-short (τL < 1 / (2 πωpe)) laser pulses drive highly nonlinear plasma waves which can trap ~ nC of electrons and accelerate them to ~GeV energies over ~cm lengths. These electron beams can then be converted by a high-Z target via bremsstrahlung into low-divergence (< 20 mrad) beams of high-energy (<600 MeV) photons and subsequently into positrons via the Bethe-Heitler process. By increasing the material thickness and Z, the resulting Ne+ /Ne- ratio can approach unity, resulting in a near neutral density plasma jet. These quasi-neutral beams are presumed to retain the short-pulse (τL < 40 fs) characteristic of the electron beam, resulting in a high peak density of ne- /e+ ~ 1016 cm-3 , making the source an excellent candidate for laboratory study of astrophysical leptonic jets. Alternatively, the electron beam can be interacted with a counter-propagating, ultra-high intensity (I >1021 W /cm2) laser pulse to undergo inverse Compton scattering and emit a high-peak brightness beam of high-energy photons. Preliminary results and experimental sensitivities of the electron-laser beam overlap are presented. The high-energy photon beams can be spectrally resolved using a forward Compton scattering spectrometer. Moreover, the photon flux can be characterized by a pixelated scintillator array and by nuclear activation and (γ,n) neutron measurements from the photons interacting with a secondary solid target. Monte-Carlo simulations were performed using FLUKA to support the yield estimates. This research was supported by DOE/NSF-PHY 0810979, NSF CAREER 1054164, DARPA AXiS N66001-11-1-4208, SF/DNDO F021166, and the Leverhulme Trust ECF-2011-383.

  12. Performance of the beam chamber vacuum system of K = 500 cyclotron at Variable Energy Cyclotron Centre Kolkata

    SciTech Connect

    Pal, Gautam DuttaGupta, Anjan; Chakrabarti, Alok

    2014-07-15

    The beam chamber of Variable Energy Cyclotron Centre, Kolkata's K = 500 superconducting cyclotron is pumped by liquid helium cooled cryopanel with liquid nitrogen cooled radiation shield. Performance of the vacuum system was evaluated by cooling the cryopanel assembly with liquid nitrogen and liquid helium. Direct measurement of beam chamber pressure is quite difficult because of space restrictions and the presence of high magnetic field. Pressure gauges were placed away from the beam chamber. The beam chamber pressure was evaluated using a Monte Carlo simulation software for vacuum system and compared with measurements. The details of the vacuum system, measurements, and estimation of pressure of the beam chamber are described in this paper.

  13. Analysis of beamed-energy ramjet/scramjet performance

    NASA Technical Reports Server (NTRS)

    Myrabo, L. N.; Powers, M. V.; Zaretzky, C. L.

    1986-01-01

    A study has been performed on a laser-heated ramjet/scramjet vehicle concept for propulsion during the air-breathing portion of an orbital launch trajectory. The concept considers axisymmetric, high-thrust vehicles with external inlets and nozzles. Conceptual design and ramjet/scramjet cycle analysis are emphasized, with propulsive energy provided by combustion of on-board fuel. The conventional ramjet/scramjet combustion chamber is replaced by a laser energy absorption chamber. The elimination of on-board propellant can result in very high thrust-to-weight ratios and payload fractions, in a vehicle with a relatively small degree of mechanical complexity. The basic vehicle has a weight of 12,250 lbf, and a diameter of 5 meters, which is close to the size of the Apollo command module. The ramjet calculations are based on a Mach 3 isentropic inlet with a 13.7 degree half-angle conical tip. The scramjet analysis considers conical inlets with 10, 15, and 30 degree half-angles. Flight Mach numbers from 2 to 20 are considered in the calculations.

  14. Beamed Energy and the Economics of Space Based Solar Power

    NASA Astrophysics Data System (ADS)

    Keith Henson, H.

    2010-05-01

    For space based solar power to replace fossil fuel, it must sell for 1-2 cents per kWh. To reach this sales price requires a launch cost to GEO of ˜100/kg. Proposed to reach this cost figure at 100 tonne/hour are two stages to GEO where a Skylon-rocket-plane first stage provides five km/sec and a laser stage provides 6.64 km/sec. The combination appears to reduce the cost to GEO to under 100/kg at a materials flow rate of ˜1 million tonnes per year, enough to initially construct 200 GW per year of power satellites. An extended Pro Forma business case indicates that peak investment to profitability might be ˜65 B. Over a 25-year period, production rises to two TW per year to undercut and replace most other sources of energy. Energy on this scale solves other supply problems such as water and liquid fuels. It could even allow removal of CO2 from the air and storage of carbon as synthetic oil in empty oil fields.

  15. Note on numerical study of the beam energy spread in NDCX-I

    SciTech Connect

    Vay, J.-L.; Seidl, P.A.; Friedman, A.

    2011-01-19

    The kinetic energy spread (defined here as the standard deviation of the beam particle energies) sets the ultimate theoretical limit on the longitudinal compression that can be attained on NDCX-I and NDCX-II. Experimental measurements will inevitably include the real influences on the longitudinal phase space of the beam due to injector and accelerator field imperfections1. These induced energy variations may be the real limit to the longitudinal compression in an accelerator. We report on a numerical investigation of the energy spread evolution in NDCX-I; these studies do not include all the real imperfections, but rather are intended to confirm that there are no other intrinsic mechanisms (translaminar effects, transverse-longitudinal anisotropy instability, etc.) for significant broadening of the energy distribution. We have performed Warp simulations that use a realistic Marx voltage waveform which was derived from experimental measurements (averaged over several shots), a fully-featured model of the accelerating and focusing lattice, and new diagnostics for computing the local energy spread (and temperature) that properly account for linear correlations that arise from the discrete binning along each physical dimension (these capabilities reproduce and extend those of the earlier HIF code BPIC). The new diagnostics allow for the calculation of multi-dimensional maps of energy spread and temperature in 2-D axisymmetric or 3-D Cartesian space at selected times. The simulated beam-line was terminated at z = 3 m by a conducting plate, so as to approximately reproduce the experimental conditions at the entrance of the spectrometer that was used for mapping the longitudinal phase space. Snapshots of the beam projection and current, as well as the Marx waveform and history of beam kinetic energy collected at the end plate, are shown in Fig. 1. A two-dimensional axisymmetric map of energy spread from simulations of a typical NDCX-I configuration is shown in Fig. 2 (a

  16. Nano-ranged low-energy ion-beam-induced DNA transfer in biological cells

    NASA Astrophysics Data System (ADS)

    Yu, L. D.; Wongkham, W.; Prakrajang, K.; Sangwijit, K.; Inthanon, K.; Thongkumkoon, P.; Wanichapichart, P.; Anuntalabhochai, S.

    2013-06-01

    Low-energy ion beams at a few tens of keV were demonstrated to be able to induce exogenous macromolecules to transfer into plant and bacterial cells. In the process, the ion beam with well controlled energy and fluence bombarded living cells to cause certain degree damage in the cell envelope in nanoscales to facilitate the macromolecules such as DNA to pass through the cell envelope and enter the cell. Consequently, the technique was applied for manipulating positive improvements in the biological species. This physical DNA transfer method was highly efficient and had less risk of side-effects compared with chemical and biological methods. For better understanding of mechanisms involved in the process, a systematic study on the mechanisms was carried out. Applications of the technique were also expanded from DNA transfer in plant and bacterial cells to DNA transfection in human cancer cells potentially for the stem cell therapy purpose. Low-energy nitrogen and argon ion beams that were applied in our experiments had ranges of 100 nm or less in the cell envelope membrane which was majorly composed of polymeric cellulose. The ion beam bombardment caused chain-scission dominant damage in the polymer and electrical property changes such as increase in the impedance in the envelope membrane. These nano-modifications of the cell envelope eventually enhanced the permeability of the envelope membrane to favor the DNA transfer. The paper reports details of our research in this direction.

  17. Measurement of electron beam polarization from the energy asymmetry of Compton scattered photons

    SciTech Connect

    Field, R.C.; Woods, M.; Zhou, J.; Frey, R.; Arodzero, A.

    1998-06-01

    The authors describe a new method for precision measurement ({approximately} 1%) of the longitudinal polarization of high-energy electron beams. The method relies on measuring the energy asymmetry of Compton scattered photons which result from collisions between the electron beam and a polarized laser beam. The measurement takes place near the electron-positron interaction point at the SLAC Linear Collider (SLC). The detector described here (PGC) is a threshold gas Cherenkov device which follows a lead radiator. The Cherenkov threshold (14 MeV) is essential for eliminating enormous synchrotron radiation-induced backgrounds at the position of interest in the SLC. They also describe the calibration of the PGC energy response in a test beam and its performance as a working polarimeter for the SLC/SLD physics program. Preliminary results from the 1996 run indicate that PGC measurement with total error at or below the 1% level is indeed achievable, and hence serves as a valuable crosscheck of the polarization scale.

  18. Radiation hygienization of cattle and swine slurry with high energy electron beam

    NASA Astrophysics Data System (ADS)

    Skowron, Krzysztof; Olszewska, Halina; Paluszak, Zbigniew; Zimek, Zbigniew; Kałuska, Iwona; Skowron, Karolina Jadwiga

    2013-06-01

    The research was carried out to assess the efficiency of radiation hygienization of cattle and swine slurry of different density using the high energy electron beam based on the inactivation rate of Salmonella ssp, Escherichia coli, Enterococcus spp and Ascaris suum eggs. The experiment was conducted with use of the linear electron accelerator Elektronika 10/10 in Institute of Nuclear Chemistry and Technology in Warsaw. The inoculated slurry samples underwent hygienization with high energy electron beam of 1, 3, 5, 7 and 10 kGy. Numbers of reisolated bacteria were determined according to the MPN method, using typical microbiological media. Theoretical lethal doses, D90 doses and hygienization efficiency of high energy electron beam were determined. The theoretical lethal doses for all tested bacteria ranged from 3.63 to 8.84 kGy and for A. suum eggs from 4.07 to 5.83 kGy. Salmonella rods turned out to be the most sensitive and Enterococcus spp were the most resistant to electron beam hygienization. The effectiveness or radiation hygienization was lower in cattle than in swine slurry and in thick than in thin one. Also the species or even the serotype of bacteria determined the dose needed to inactivation of microorganisms.

  19. Investigation of beamed-energy ERH thruster performance

    NASA Technical Reports Server (NTRS)

    Myrabo, Leik N.; Strayer, T. Darton; Bossard, John A.; Richard, Jacques C.; Gallimore, Alec D.

    1986-01-01

    The objective of this study was to determine the performance of an External Radiation Heated (ERH) thruster. In this thruster, high intensity laser energy is focused to ignite either a Laser Supported Combustion (LSC) wave or a Laser Supported Detonation (LSD) wave. Thrust is generated as the LSC or LSD wave propagates over the thruster's surface, or in the proposed thruster configuration, the vehicle afterbody. Thrust models for the LSC and LSD waves were developed and simulated on a computer. Performance parameters investigated include the effect of laser intensity, flight Mach number, and altitude on mean-thrust and coupling coefficient of the ERH thruster. Results from these models suggest that the ERH thruster using LSC/LSD wave ignition could provide propulsion performance considerably greater than any propulsion system currently available.

  20. Bi-stable energy harvesting based on a simply supported piezoelectric buckled beam

    NASA Astrophysics Data System (ADS)

    Xu, Chundong; Liang, Zhu; Ren, Bo; Di, Wenning; Luo, Haosu; Wang, Dong; Wang, Kailing; Chen, Zhifang

    2013-09-01

    Bi-stable piezoelectric energy harvester has been found as a promising structure for vibration energy harvesting. This paper presents a high performance and simple structure bi-stable piezoelectric energy harvester based on simply supported piezoelectric buckled beam. The potential energy function is established theoretically, and electrical properties of the device under different axial compressive displacements, excitation frequencies, and accelerations are investigated systematically. Experimental results demonstrate that the output properties and bandwidth of the bi-stable nonlinear energy harvester under harmonic mechanical excitation are improved dramatically compared with the traditional linear energy harvester. The device demonstrates the potential in energy harvesting application to low-power portable electronics and wireless sensor nodes.

  1. Internal energy flows of coma-affected singular beams in low-numerical-aperture systems.

    PubMed

    Bahl, Monika; Singh, Brijesh Kumar; Singh, Rakesh Kumar; Senthilkumaran, P

    2015-04-01

    The circulating phase gradient component of a singular beam gets modified when focused by a low-numerical-aperature system suffering from coma aberration. The gradient due to this coma aberration splits the higher charge vortex into elementary vortices and distributes them spatially. This splitting depends on the charge and polarity of the incident singular beam as well as the sign and magnitude of the aberration coefficient. The transverse component of the Poynting vector field distribution at the focal plane is decomposed into the curl or solenoidal component and divergence or irrotational component using the Helmholtz-Hodge decomposition technique. The solenoidal component that relates to the orbital angular momentum carries the circulating energy, while the irrotational component shows the sources and sinks of the energy. Intriguing results of the study of energy flow around the edge dislocations apart from the point phase defects in the irrotational components are also presented.

  2. Energy harvesting from coherent resonance of horizontal vibration of beam excited by vertical base motion

    SciTech Connect

    Lan, C. B.; Qin, W. Y.

    2014-09-15

    This letter investigates the energy harvesting from the horizontal coherent resonance of a vertical cantilever beam subjected to the vertical base excitation. The potential energy of the system has two symmetric potential wells. So, under vertical excitation, the system can jump between two potential wells, which will lead to the large vibration in horizontal direction. Two piezoelectric patches are pasted to harvest the energy. From experiment, it is found that the vertical excitation can make the beam turn to be bistable. The system can transform vertical vibration into horizontal vibration of low frequency when excited by harmonic motion. The horizontal coherence resonance can be observed when excited by a vertical white noise. The corresponding output voltages of piezoelectric films reach high values.

  3. Modeling of energy transfer between two crossing smoothed laser beams in a plasma with flow profile

    NASA Astrophysics Data System (ADS)

    Colaitis, A.; Hüller, S.; Tikhonchuk, V. T.; Pesme, D.; Duchateau, G.; Porzio, A.

    2016-05-01

    We study the crossed beam energy transfer (CBET) between laser fields generated by optical smoothing methods. The energy transfer, as well as the angular distribution of the outgoing light fields are investigated for two incident smoothed laser beams in a plasma with a flow gradient, allowing for resonant transfer close to the sonic point. Simulations with the code HARMONY based on time-dependent paraxial light propagation are compared to simulations using a new approach based on paraxial complex geometrical optics (PCGO). Both approaches show good agreement for the average energy transfer past a short transient period, which is a promising result for the use of the PCGO method as a module within a hydrodynamics code to efficiently compute CBET in mm-scale plasma configurations. Statistical aspects related to role of laser speckles in CBET are considered via an ensemble of different phase plate realizations.

  4. Energy spreading and angular distribution of a beam of electrons in molecular hydrogen

    NASA Technical Reports Server (NTRS)

    Heaps, M. G.; Green, A. E. S.

    1975-01-01

    A Monte Carlo approach is used to obtain the energy spreading and angular distribution of initially monoenergetic and monodirectional beams of electron incident on a gas of molecular hydrogen. Several beams of primary electrons and the resultant secondaries are degraded in a step-by-step procedure which utilizes a detailed set of cross sections, together with reasonable approximations for the creation of secondary electrons. Particular attention is paid to the initial angular distribution of secondary electrons. An analytic function which characterizes current experimental differential cross-section data is used to provide realistic inputs into our calculations. The results for energy distribution as a function of distance and angular distribution at selected energies and distances are illustrated.

  5. Selective in-plane nitrogen doping of graphene by an energy-controlled neutral beam

    NASA Astrophysics Data System (ADS)

    Okada, Takeru; Samukawa, Seiji

    2015-12-01

    Nitrogen-doped graphene promises to improve current electronic devices, sensors, and energy-based devices. To this end, the bonding states between carbon and nitrogen atoms can be manipulated to tailor the properties of the doped graphene. For example, graphitic nitrogen is known to promote desired catalytic activities in graphene fuel-cell systems, resulting from a four-electron reaction. However, established nitrogen-doping methods lack selectivity in dopant chemical identity and in dopant location; both are key factors in graphene property design because the properties depend on the chemical identity and location of the dopant. Here, we utilize a nitrogen neutral beam (NB) technique—with exquisite beam energy control—to dope graphene with nitrogen. Using x-ray photoelectron and Raman spectroscopy, we show that the energy of the nitrogen NB not only determines the chemistry of the nitrogen dopant introduced to graphene, but it also dictates the doping locations within graphene layers.

  6. Dense Plasma Focus With High Energy Helium Beams for Radiological Source Replacement

    NASA Astrophysics Data System (ADS)

    Schmidt, Andrea; Ellsworth, Jennifer; Falabella, Steve; Link, Anthony; Rusnak, Brian; Sears, Jason; Tang, Vincent

    2014-10-01

    A dense plasma focus (DPF) is a compact accelerator that can produce intense high energy ion beams (multiple MeV). It could be used in place of americium-beryllium (AmBe) neutron sources in applications such as oil well logging if optimized to produce high energy helium beams. AmBe sources produce neutrons when 5.5 MeV alphas emitted from the Am interact with the Be. However, due to the very small alpha-Be cross section for alphas <2 MeV, an AmBe source replacement would have to accelerate ~0.15 μC of He to 2 + MeV in order to produce 107 neutrons per pulse. We are using our particle in cell (PIC) model in LSP of a 4 kJ dense plasma focus discharge to guide the optimization of a compact DPF for the production of high-energy helium beam. This model is fluid for the run-down phase, and then transitions to fully kinetic prior to the pinch in order to include kinetic effects such as ion beam formation and anomalous resistivity. An external pulsed-power driver circuit is used at the anode-cathode boundary. Simulations will be benchmarked to He beam measurements using filtered and time-of-flight Faraday cup diagnostics. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work supported by US DOE/NA-22 Office of Non-proliferation Research and Development. Computing support for this work came from the LLNL Institutional Computing Grand Challenge program.

  7. Three-dimensional piezoelectric vibration energy harvester using spiral-shaped beam with triple operating frequencies.

    PubMed

    Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping

    2016-01-01

    This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life. PMID:26827346

  8. Three-dimensional piezoelectric vibration energy harvester using spiral-shaped beam with triple operating frequencies

    NASA Astrophysics Data System (ADS)

    Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping

    2016-01-01

    This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life.

  9. Thermal Acoustic Sensor for High Pulse Energy X-ray FEL Beams

    SciTech Connect

    Smith, T.J.; Frisch, J.C.; Kraft, E.M.; Loos, J.; Bentsen, G.S.; /Rochester U.

    2011-12-13

    The pulse energy density of X-ray FELs will saturate or destroy conventional X-ray diagnostics, and the use of large beam attenuation will result in a beam that is dominated by harmonics. We present preliminary results at the LCLS from a pulse energy detector based on the thermal acoustic effect. In this type of detector an X-ray resistant material (boron carbide in this system) intercepts the beam. The pulse heating of the target material produces an acoustic pulse that can be detected with high frequency microphones to produce a signal that is linear in the absorbed energy. The thermal acoustic detector is designed to provide first- and second-order calorimetric measurement of X-ray FEL pulse energy. The first-order calorimetry is a direct temperature measurement of a target designed to absorb all or most of the FEL pulse power with minimal heat leak. The second-order measurement detects the vibration caused by the rapid thermoelastic expansion of the target material each time it absorbs a photon pulse. Both the temperature change and the amplitude of the acoustic signal are directly related to the photon pulse energy.

  10. Three-dimensional piezoelectric vibration energy harvester using spiral-shaped beam with triple operating frequencies.

    PubMed

    Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping

    2016-01-01

    This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life.

  11. First polarized proton collision at a beam energy of 250 GeV in RHIC

    SciTech Connect

    Bai,M.; Ahrens, L.; Alekseev, I. G.; Alessi, J.; et al.

    2009-05-04

    After providing collisions of polarized protons at a beam energy of 100 GeV since 2001, the Relativistic Heavy Ion Collider (RHIC) at BNL had its first opportunity to collide polarized protons at its maximum beam energy of 250 GeV in the 2009 polarized proton operations. Equipped with two full Siberian snakes [1] in each ring, RHIC preserves polarization during acceleration from injection to 100 GeV with precise control of the betatron tunes and vertical orbit distortions. However, the strong intrinsic spin resonances beyond 100 GeV are more than two times stronger than those below 100 GeV, requiring much tighter tolerances on vertical orbit distortions and betatron tunes. With the currently achieved orbit correction and tune control, average polarizations of {approx_equal} 42% at top energy and average polarizations of {approx_equal} 55% at injection energy were achieved. Polarization measurements as a function of beam energy also indicated aU polarization losses occurred around three strong intrinsic resonances at 136 GeV, 199.3 GeV and 220.8 GeV Peak luminosity of 122 x 10{sup 30} cm{sup -2} s{sup -1} was also demonstrated. This paper presents the performance of the first RHIC 250 GeV operation and discusses the depolarization issues encountered during the run.

  12. Fabrication of Pt nanoparticle incorporated polymer nanowires by high energy ion and electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Tsukuda, Satoshi; Takahasi, Ryouta; Seki, Shu; Sugimoto, Masaki; Idesaki, Akira; Yoshikawa, Masahito; Tanaka, Shun-Ichiro

    2016-01-01

    Polyvinylpyrrolidone (PVP)-Pt nanoparticles (NPs) hybrid nanowires were fabricated by high energy ion beam irradiation to PVP thin films including H2PtCl6. Single ion hitting caused crosslinking reactions of PVP and reduction of Pt ions within local cylindrical area along an ion trajectory (ion track); therefore, the PVP nanowires including Pt NPs were formed and isolated on Si substrate after wet-development procedure. The number of Pt NPs was easily controlled by the mixed ratio of PVP and H2PtCl6. However, increasing the amount of H2PtCl6 led to decreasing the radial size and separation of the hybrid nanowires during the wet-development. Additional electron beam irradiation after ion beam improved separation of the nanowires and controlled radial sizes due to an increase in the density of crosslinking points inner the nanowires.

  13. Device and method for generating a beam of acoustic energy from a borehole, and applications thereof

    SciTech Connect

    Vu, Cung Khac; Sinha, Dipen N.; Pantea, Cristian; Nihei, Kurt T.; Schmitt, Denis P.; Skelt, Chirstopher

    2013-10-15

    In some aspects of the invention, a method of generating a beam of acoustic energy in a borehole is disclosed. The method includes generating a first acoustic wave at a first frequency; generating a second acoustic wave at a second frequency different than the first frequency, wherein the first acoustic wave and second acoustic wave are generated by at least one transducer carried by a tool located within the borehole; transmitting the first and the second acoustic waves into an acoustically non-linear medium, wherein the composition of the non-linear medium produces a collimated beam by a non-linear mixing of the first and second acoustic waves, wherein the collimated beam has a frequency based upon a difference between the first frequency range and the second frequency, and wherein the non-linear medium has a velocity of sound between 100 m/s and 800 m/s.

  14. Note: High-efficiency broadband acoustic energy harvesting using Helmholtz resonator and dual piezoelectric cantilever beams

    SciTech Connect

    Yang, Aichao; Li, Ping Wen, Yumei; Lu, Caijiang; Peng, Xiao; He, Wei; Zhang, Jitao; Wang, Decai; Yang, Feng

    2014-06-15

    A high-efficiency broadband acoustic energy harvester consisting of a compliant-top-plate Helmholtz resonator (HR) and dual piezoelectric cantilever beams is proposed. Due to the high mechanical quality factor of beams and the strong multimode coupling of HR cavity, top plate and beams, the high efficiency in a broad bandwidth is obtained. Experiment exhibits that the proposed harvester at 170–206 Hz has 28–188 times higher efficiency than the conventional harvester using a HR with a piezoelectric composite diaphragm. For input acoustic pressure of 2.0 Pa, the proposed harvester exhibits 0.137–1.43 mW output power corresponding to 0.035–0.36 μW cm{sup −3} volume power density at 170–206 Hz.

  15. Note: High-efficiency broadband acoustic energy harvesting using Helmholtz resonator and dual piezoelectric cantilever beams.

    PubMed

    Yang, Aichao; Li, Ping; Wen, Yumei; Lu, Caijiang; Peng, Xiao; He, Wei; Zhang, Jitao; Wang, Decai; Yang, Feng

    2014-06-01

    A high-efficiency broadband acoustic energy harvester consisting of a compliant-top-plate Helmholtz resonator (HR) and dual piezoelectric cantilever beams is proposed. Due to the high mechanical quality factor of beams and the strong multimode coupling of HR cavity, top plate and beams, the high efficiency in a broad bandwidth is obtained. Experiment exhibits that the proposed harvester at 170-206 Hz has 28-188 times higher efficiency than the conventional harvester using a HR with a piezoelectric composite diaphragm. For input acoustic pressure of 2.0 Pa, the proposed harvester exhibits 0.137-1.43 mW output power corresponding to 0.035-0.36 μW cm(-3) volume power density at 170-206 Hz. PMID:24985867

  16. A new medium energy beam transport line for the proton injector of AGS-RHIC

    SciTech Connect

    Okamura, M.; Briscoe, B.; Fite, J.; LoDestro, V.; Raparia, D.; Ritter, J.; Hayashizaki, N.

    2010-09-12

    In Brookhaven National Laboratory (BNL), a 750 keV medium energy beam transport line between the 201 MHz 750 keV proton RFQ and the 200 MeV Alvarez DTL is being modified to get a better transmission of the beam. Within a tight space, high field gradient quadrupoles (65 Tm) and newly designed steering magnets (6.5 mm in length) will be installed considering the cross-talk effects. Also a new half wave length 200 MHz buncher is being prepared. The beam commissioning will be done in this year. To enhance the performance of the proton linacs, the MEBT is being modified. New quadrupole magnets, steering magnets and a half wave length buncher as shown in Figure 7 will be installed and be commissioned soon.

  17. Induction of Micronuclei in Human Fibroblasts from the Los Alamos High Energy Neutron Beam

    NASA Technical Reports Server (NTRS)

    Cox, Bradley

    2009-01-01

    The space radiation field includes a broad spectrum of high energy neutrons. Interactions between these neutrons and a spacecraft, or other material, significantly contribute to the dose equivalent for astronauts. The 15 degree beam line in the Weapons Neutron Research beam at Los Alamos Nuclear Science Center generates a neutron spectrum relatively similar to that seen in space. Human foreskin fibroblast (AG1522) samples were irradiated behind 0 to 20 cm of water equivalent shielding. The cells were exposed to either a 0.05 or 0.2 Gy entrance dose. Following irradiation, micronuclei were counted to see how the water shield affects the beam and its damage to cell nuclei. Micronuclei induction was then compared with dose equivalent data provided from a tissue equivalent proportional counter.

  18. Dynamics of Finite Energy Airy Beams Carrying Orbital Angular Momentum in Multilevel Atomic Vapors

    NASA Astrophysics Data System (ADS)

    Wu, Zhenkun; Wang, Shun; Hu, Weifei; Gu, Yuzong

    2016-10-01

    We numerically investigate the dynamics of inward circular finite-energy Airy beams carrying different orbital angular momentum (OAM) numbers in a close-Λ three-level atomic vapor with the electromagnetically induced transparency (EIT) window. We report that due to the EIT induced by the microwave field, the transverse intensity distribution properties of Airy beam can be feasibly manipulated and modulated through adjusting OAM numbers l and the frequency detuning, as well as the propagation distance, in the multi-level atomic systems. What's more, the rotation of the beam also can be observed with different positions in atomic ensembles. The investigation may provide a useful tool for studying particle manipulation, signal processing and propagation in graded-index (GRIN) fibers.

  19. The impact of charging on low-energy electron beam lithography.

    PubMed

    Mun, Lau Kien; Drouin, Dominique; Lavallée, Eric; Beauvais, Jacques

    2004-12-01

    A major issue in low voltage lithography is surface charging, which results in beam deflection presented as uneven exposure between adjacent structures. In this study, charge-induced pattern distortions in low-voltage energy beam lithography (LVEBL) were investigated using a silicide direct-write electron beam lithography process. Two methodologies have been proposed to avert charging effects in LVEBL, namely, pattern randomizing and lithography using the crossover voltage. Experimental results demonstrated that these methods are effective in significantly reducing the problems associated with charging. They indicate that charging on a sample is a function of time interval and proximity between line structures. In addition, the optimum time and distance between exposures for no charge-induced pattern distortion were determined. By using the crossover voltage of the material for lithography, charging effect can be significantly minimized. PMID:19780323

  20. Determination of interfacial states in solid heterostructures using a variable-energy positron beam

    DOEpatents

    Asokakumar, P.P.V.; Lynn, K.G.

    1993-04-06

    A method and means is provided for characterizing interfacial electron states in solid heterostructures using a variable energy positron beam to probe the solid heterostructure. The method includes the steps of directing a positron beam having a selected energy level at a point on the solid heterostructure so that the positron beam penetrates into the solid heterostructure and causes positrons to collide with the electrons at an interface of the solid heterostructure. The number and energy of gamma rays emitted from the solid heterostructure as a result of the annihilation of positrons with electrons at the interface are detected. The data is quantified as a function of the Doppler broadening of the photopeak about the 511 keV line created by the annihilation of the positrons and electrons at the interface, preferably, as an S-parameter function; and a normalized S-parameter function of the data is obtained. The function of data obtained is compared with a corresponding function of the Doppler broadening of the annihilation photopeak about 511 keV for a positron beam having a second energy level directed at the same material making up a portion of the solid heterostructure. The comparison of these functions facilitates characterization of the interfacial states of electrons in the solid heterostructure at points corresponding to the penetration of positrons having the particular energy levels into the interface of the solid heterostructure. Accordingly, the invention provides a variable-energy non-destructive probe of solid heterostructures, such as SiO[sub 2]/Si, MOS or other semiconductor devices.

  1. Determination of interfacial states in solid heterostructures using a variable-energy positron beam

    DOEpatents

    Asoka kumar, Palakkal P. V.; Lynn, Kelvin G.

    1993-01-01

    A method and means is provided for characterizing interfacial electron states in solid heterostructures using a variable energy positron beam to probe the solid heterostructure. The method includes the steps of directing a positron beam having a selected energy level at a point on the solid heterostructure so that the positron beam penetrates into the solid heterostructure and causes positrons to collide with the electrons at an interface of the solid heterostructure. The number and energy of gamma rays emitted from the solid heterostructure as a result of the annihilation of positrons with electrons at the interface are detected. The data is quantified as a function of the Doppler broadening of the photopeak about the 511 keV line created by the annihilation of the positrons and electrons at the interface, preferably, as an S-parameter function; and a normalized S-parameter function of the data is obtained. The function of data obtained is compared with a corresponding function of the Doppler broadening of the annihilation photopeak about 511 keV for a positron beam having a second energy level directed at the same material making up a portion of the solid heterostructure. The comparison of these functions facilitates characterization of the interfacial states of electrons in the solid heterostructure at points corresponding to the penetration of positrons having the particular energy levels into the interface of the solid heterostructure. Accordingly, the invention provides a variable-energy non-destructive probe of solid heterostructures, such as SiO.sub.2 /Si, MOS or other semiconductor devices.

  2. Energy monitoring device for 1.5-2.4 MeV electron beams

    NASA Astrophysics Data System (ADS)

    Fuochi, P. G.; Lavalle, M.; Martelli, A.; Kovács, A.; Mehta, K.; Kuntz, F.; Plumeri, S.

    2010-03-01

    An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

  3. Nonlinear and long-term beam dynamics in low energy storage rings

    NASA Astrophysics Data System (ADS)

    Papash, A. I.; Smirnov, A. V.; Welsch, C. P.

    2013-06-01

    Electrostatic storage rings operate at very low energies in the keV range and have proven to be invaluable tools for atomic and molecular physics. Because of the mass independence of electric rigidity, these machines are able to store a wide range of different particles, from light ions to heavy singly charged biomolecules, opening up unique research opportunities. However, earlier measurements have shown strong limitations in maximum beam intensity, fast decay of the stored ion current, and reduced beam lifetime. The nature of these effects has not been fully understood and an improved understanding of the physical processes influencing beam motion and stability in such rings is needed. In this paper, a comprehensive study into nonlinear and long-term beam dynamics studies is presented on the examples of a number of existing and planned electrostatic storage rings using the BETACOOL, OPERA-3D, and MAD-X simulation software. A detailed investigation into ion kinetics, under consideration of effects from electron cooling and multiple scattering of the beam on a supersonic gas jet target, is carried out and yields a consistent explanation of the physical effects in a whole class of storage rings. The lifetime, equilibrium momentum spread, and equilibrium lateral spread during collisions with the target are estimated. In addition, the results from experiments at the Test Storage Ring, where a low-intensity beam of CF+ ions at 93keV/u has been shrunk to extremely small dimensions, are reproduced. Based on these simulations, the conditions for stable ring operation with an extremely low-emittance beam are presented. Finally, results from studies into the interaction of 3-30 keV ions with a gas jet target are summarized.

  4. Activities on heavy ion inertial fusion and beam-driven high energy density science in Japan

    NASA Astrophysics Data System (ADS)

    Horioka, K.; Kawamura, T.; Nakajima, M.; Kondo, K.; Ogawa, M.; Oguri, Y.; Hasegawa, J.; Kawata, S.; Kikuchi, T.; Sasaki, T.; Murakami, M.; Takayama, K.

    2009-07-01

    Recent research activities in Japan relevant to heavy ion fusion (HIF) are presented. During the past two years, significant progress in HIF and high energy density (HED) physics research has been made by a number of research groups in universities and accelerator facilities. Evolutions in phase space during the longitudinal compression of intense beams were investigated at UU-NUT-TIT. Beam-plasma interaction experiments and related theoretical studies are in progress at RLNR-TIT. In the study, shock-heated hydrogen was used for the interaction experiments as a well-defined non-ideal-plasma target. In the beam-plasma interaction experiments, a special emphasis is placed on an evaluation of non-linear effects on the stopping power in a beam-heated plasma target. A direct-indirect hybrid scheme of a beam-driven ICF target has been proposed and discussed at UU. In the same group, a method for controlling the Rayleigh-Taylor instability in imploding fuel target has been proposed using oscillating heavy ion beams (HIBs). Core dynamics of the impact ignition has been investigated both experimentally and numerically at ILE—Osaka. Dense plasmas driven by intense ion beams and/or a pulse powered device, were evaluated by a group of DES-TIT, concerning the researches on HED and warm dense matter (WDM) physics. A quasi-statically tamped target was proposed to make a well-defined, warm dense state for equation-of-state (EOS) studies based on ion accelerators. The potentiality of the new facility planned at KEK was evaluated by a collaborating group of TIT-UU-KEK, which can extend the parameter regime for laboratory experiments to study the properties of matter under extreme conditions. A possible method to make a high-pressure condition for study of the planetary science was discussed as a short-term subject of intense HIBs.

  5. Early and delayed reproductive death in human cells exposed to high energy iron-ion beams

    NASA Astrophysics Data System (ADS)

    Bettega, D.; Calzolari, P.; Doneda, L.; Durante, M.; Tallone, L.

    For radiation protection of the astronauts it is important to know both the acute and the late effects of charged particles. Iron is the most abundant high charge and energy (HZE) specie in galactic cosmic radiation. (HZE) ions are considered to be the major contributors to equivalent dose in space, but the Relative Biological Effectiveness of HZE particles has large uncertainties, expecially for late effects. We have determined early and delayed reproductive death in human fibroblast cells (AG1522) exposed to iron ion beams of energies between 0.2 and 1 GeV/n. The cells were irradiated at the HIMAC accelerator in Chiba (0.2 and 0.5 GeV/n) and at the AGS accelerator at the NASA Space Radiation Laboratory in Brookhaven (1 GeV/n). For each beam the dose--effect curves were measured at least twice in the dose range between 0.5 and 2 Gy. 60 Co gamma rays were used as reference radiation. The following results were obtained: 1) the 1 GeV/n beam effectiveness for inactivation of the AG1522 cells is higher than that of any other beam. 2) the progeny of the irradiated cells show the presence of delayed damage in the form of reproductive death for all the beams with the 1 GeV/n being the most effective. 3) the relative biological effectiveness of the iron beams is higher for delayed compared to early reproductive death. A comparison with preliminary results obtained with 970 MeV/n Ti and 490 MeV/n Si ions will be also reported .

  6. Optimal piezoelectric beam shape for single and broadband vibration energy harvesting: Modeling, simulation and experimental results

    NASA Astrophysics Data System (ADS)

    Muthalif, Asan G. A.; Nordin, N. H. Diyana

    2015-03-01

    Harvesting energy from the surroundings has become a new trend in saving our environment. Among the established ones are solar panels, wind turbines and hydroelectric generators which have successfully grown in meeting the world's energy demand. However, for low powered electronic devices; especially when being placed in a remote area, micro scale energy harvesting is preferable. One of the popular methods is via vibration energy scavenging which converts mechanical energy (from vibration) to electrical energy by the effect of coupling between mechanical variables and electric or magnetic fields. As the voltage generated greatly depends on the geometry and size of the piezoelectric material, there is a need to define an optimum shape and configuration of the piezoelectric energy scavenger. In this research, mathematical derivations for unimorph piezoelectric energy harvester are presented. Simulation is done using MATLAB and COMSOL Multiphysics software to study the effect of varying the length and shape of the beam to the generated voltage. Experimental results comparing triangular and rectangular shaped piezoelectric beam are also presented.

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Monte Carlo-based energy response studies of diode dosimeters in radiotherapy photon beams.

    PubMed

    Arun, C; Palani Selvam, T; Dinkar, Verma; Munshi, Prabhat; Kalra, Manjit Singh

    2013-01-01

    This study presents Monte Carlo-calculated absolute and normalized (relative to a (60)Co beam) sensitivity values of silicon diode dosimeters for a variety of commercially available silicon diode dosimeters for radiotherapy photon beams in the energy range of (60)Co-24 MV. These values were obtained at 5 cm depth along the central axis of a water-equivalent phantom of 10 cm × 10 cm field size. The Monte Carlo calculations were based on the EGSnrc code system. The diode dosimeters considered in the calculations have different buildup materials such as aluminum, brass, copper, and stainless steel + epoxy. The calculated normalized sensitivity values of the diode dosimeters were then compared to previously published measured values for photon beams at (60)Co-20 MV. The comparison showed reasonable agreement for some diode dosimeters and deviations of 5-17 % (17 % for the 3.4 mm brass buildup case for a 10 MV beam) for some diode dosimeters. Larger deviations of the measurements reflect that these models of the diode dosimeter were too simple. The effect of wall materials on the absorbed dose to the diode was studied and the results are presented. Spencer-Attix and Bragg-Gray stopping power ratios (SPRs) of water-to-diode were calculated at 5 cm depth in water. The Bragg-Gray SPRs of water-to-diode compare well with Spencer-Attix SPRs for ∆ = 100 keV and above at all beam qualities.

  9. Beam-dynamics driven design of the LHeC energy-recovery linac

    DOE PAGESBeta

    Pellegrini, Dario; Latina, Andrea; Schulte, Daniel; Bogacz, S. Alex

    2015-12-23

    The LHeC study is a possible upgrade of the LHC that aims at delivering an electron beam for collisions with the existing hadronic beams. The current baseline design for the electron facility consists of a multi-pass superconducting energy-recovery linac operating in a continuous wave mode. Here, we summarize the overall layout of such ERL complex located on the LHC site and introduce the most recent developments. We review of the lattice components, presenting their baseline design along with possible alternatives that aims at improving the overall machine performance. The detector bypass has been designed and integrated into the lattice. Trackingmore » simulations allowed us to verify the high current (~150 mA in the linacs) beam operation required for the LHeC to serve as an Higgs Factory. The impact of single and multi-bunch wake-fields, synchrotron radiation and beam-beam effects has been assessed in this paper.« less

  10. Collective Focusing of Intense Ion Beam Pulses for High-energy Density Physics Applications

    SciTech Connect

    Dorf, Mikhail A.; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

    2011-04-27

    The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson Phys. Rev. Lett. 48, 149 (1982) is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I) , and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations. 2011 American Institute of Physics

  11. Collective focusing of intense ion beam pulses for high-energy density physics applications

    SciTech Connect

    Dorf, Mikhail A.; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

    2011-03-15

    The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson [Phys. Rev. Lett. 48, 149 (1982)] is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I), and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations.

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

    PubMed

    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.

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

    SciTech Connect

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

    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.

  14. Generation of high-energy neutron beam by fragmentation of relativistic heavy nuclei

    NASA Astrophysics Data System (ADS)

    Yurevich, Vladimir

    2016-09-01

    The phenomenon of multiple production of neutrons in reactions with heavy nuclei induced by high-energy protons and light nuclei is analyzed using a Moving Source Model. The Lorentz transformation of the obtained neutron distributions is used to study the neutron characteristics in the inverse kinematics where relativistic heavy nuclei bombard a light-mass target. The neutron beam generated at 0∘has a Gaussian shape with a maximum at the energy of the projectile nucleons and an energy resolution σE/E < 4% above 6 GeV.

  15. Investigation of Charge Transfer in Low Energy D2+ + H Collisions using Merged Beams

    SciTech Connect

    Andrianarijaona, Vola M; Rada, J. J.; Rejoub, Riad A; Havener, Charles C

    2009-01-01

    Synopsis The hydrogen - hydrogen (deuterium) molecular ion is the most fundamental ion-molecule two-electron system. Charge transfer proceeds through dynamically coupled electronic, vibrational and rotational degrees of freedom. Using the ion-atom merged-beams apparatus at Oak Ridge National Laboratory absolute charge transfer cross sections for D2+ + H are measured from keV/u collision energies where the collision is considered "ro-vibrationally frozen" to meV/u energies where collision times are long enough to sample vibrational and rotational modes. The measurements benchmark high energy theory and vibrationally specific adiabatic theory.

  16. Estimates of HE-LHC beam parameters at different injection energies

    SciTech Connect

    Sen, Tanaji; /Fermilab

    2010-11-01

    A future upgrade to the LHC envisions increasing the top energy to 16.5 TeV and upgrading the injectors. There are two proposals to replace the SPS as the injector to the LHC. One calls for a superconducting ring in the SPS tunnel while the other calls for an injector (LER) in the LHC tunnel. In both scenarios, the injection energy to the LHC will increase. In this note we look at some of the consequences of increased injection energy to the beam dynamics in the LHC.

  17. Absolute Beam Energy Measurement using Elastic ep Scattering at Thomas Jefferson National Accelerator Facility

    NASA Astrophysics Data System (ADS)

    Deur, Alexandre

    1999-10-01

    The Jefferson Lab beam energy measurement in Hall A using the elastic ep scattering will be described. This new, non-magnetic, energy measurement method allows a ( triangle E/E=10-4 ) precision. First-order corrections are canceled by the measurements of the electron and proton scattering angles for two symmetric kinematics. The measurement principle will be presented as well as the device and measurement results. Comparison with independent magnetic energy measurements of the same accuracy will be shown. This project is the result of a collaboration between the LPC: université Blaise Pascal/in2p3), Saclay and Jefferson Lab.

  18. The energy transfer in the TEMP-4M pulsed ion beam accelerator

    SciTech Connect

    Isakova, Y. I.; Pushkarev, A. I.; Khaylov, I. P.

    2013-07-15

    The results of a study of the energy transfer in the TEMP-4M pulsed ion beam accelerator are presented. The energy transfer efficiency in the Blumlein and a self-magnetically insulated ion diode was analyzed. Optimization of the design of the accelerator allows for 85% of energy transferred from Blumlein to the diode (including after-pulses), which indicates that the energy loss in Blumlein and spark gaps is insignificant and not exceeds 10%–12%. Most losses occur in the diode. The efficiency of energy supplied to the diode to the energy of accelerated ions is 8%–9% for a planar strip self-magnetic MID, 12%–15% for focusing diode and 20% for a spiral self-magnetic MID.

  19. Time-resolved electron beam energy spectrum diagnostics for Vanderbilt FEL

    NASA Astrophysics Data System (ADS)

    Feng, Bibo; Kozub, John A.; Gabella, William E.

    2002-06-01

    A fast electron energy spectrometer has been built using a photodiode array measuring the backward optical transition radiation from a thin film of aluminum. The resolution of the electron energy spectrometer is about 0.2% with a time resolution of 50 ns. The maximum energy spread that can be measured is 6.4%. We present the measurements of the time-resolved electron beam energy spectrum on the Mark III linear accelerator at Vanderbilt University, while lasing at different wavelengths and while not lasing. We also discuss the effects of different parameters, such as cathode heating, alpha magnet strength and RF phase, on the electron energy spectrum and optical spectrum. The diagnostics of time-resolved electron energy spectrum and time-resolved laser spectrum provide the technology to understand the physical process of the FEL interaction. Based on these diagnostics, the FEL facility can realize some special modes of operation, such as macropulse chirping and macropulse two color lasing.

  20. Pencil beam approach for correcting the energy dependence artifact in film dosimetry for IMRT verification.

    PubMed

    Kirov, Assen S; Caravelli, Gregory; Palm, Asa; Chui, Chen; LoSasso, Thomas

    2006-10-01

    The higher sensitivity to low-energy scattered photons of radiographic film compared to water can lead to significant dosimetric error when the beam quality varies significantly within a field. Correcting for this artifact will provide greater accuracy for intensity modulated radiation therapy (IMRT) verification dosimetry. A procedure is developed for correction of the film energy-dependent response by creating a pencil beam kernel within our treatment planning system to model the film response specifically. Film kernels are obtained from EGSnrc Monte Carlo simulations of the dose distribution from a 1 mm diameter narrow beam in a model of the film placed at six depths from 1.5 to 40 cm in polystyrene and solid water phantoms. Kernels for different area phantoms (50 x 50 cm2 and 25 x 25 cm2 polystyrene and 30 x 30 cm2 solid water) are produced. The Monte Carlo calculated kernel is experimentally verified with film, ion chamber and thermoluminescent dosimetry (TLD) measurements in polystyrene irradiated by a narrow beam. The kernel is then used in convolution calculations to, predict the film response in open and IMRT fields. A 6 MV photon beam and Kodak XV2 film in a polystyrene phantom are selected to test the method as they are often used in practice and can result in large energy-dependent artifacts. The difference in dose distributions calculated with the film kernel and the water kernel is subtracted from film measurements to obtain a practically film artifact free IMRT dose distribution for the Kodak XV2 film. For the points with dose exceeding 5 cGy (11% of the peak dose) in a large modulated field and a film measurement inside a large polystyrene phantom at depth of 10 cm, the correction reduces the fraction of pixels for which the film dose deviates from dose to water by more than 5% of the mean film dose from 44% to 6%.

  1. A Kinematically Beamed, Low Energy Pulsed Neutron Source for Active Interrogation

    SciTech Connect

    Dietrich, D; Hagmann, C; Kerr, P; Nakae, L; Rowland, M; Snyderman, N; Stoeffl, W; Hamm, R

    2004-10-07

    We are developing a new active interrogation system based on a kinematically focused low energy neutron beam. The key idea is that one of the defining characteristics of SNM (Special Nuclear Materials) is the ability for low energy or thermal neutrons to induce fission. Thus by using low energy neutrons for the interrogation source we can accomplish three goals, (1) Energy discrimination allows us to measure the prompt fast fission neutrons produced while the interrogation beam is on; (2) Neutrons with an energy of approximately 60 to 100 keV do not fission 238U and Thorium, but penetrate bulk material nearly as far as high energy neutrons do and (3) below about 100keV neutrons lose their energy by kinematical collisions rather than via the nuclear (n,2n) or (n,n') processes thus further simplifying the prompt neutron induced background. 60 keV neutrons create a low radiation dose and readily thermal capture in normal materials, thus providing a clean spectroscopic signature of the intervening materials. The kinematically beamed source also eliminates the need for heavy backward and sideway neutron shielding. We have designed and built a very compact pulsed neutron source, based on an RFQ proton accelerator and a lithium target. We are developing fast neutron detectors that are nearly insensitive to the ever-present thermal neutron and neutron capture induced gamma ray background. The detection of only a few high energy fission neutrons in time correlation with the linac pulse will be a clear indication of the presence of SNM.

  2. Ultralow frequency acoustic bandgap and vibration energy recovery in tetragonal folding beam phononic crystal

    NASA Astrophysics Data System (ADS)

    Gao, Nansha; Wu, Jiu Hui; Yu, Lie; Hou, Hong

    2016-06-01

    This paper investigates ultralow frequency acoustic properties and energy recovery of tetragonal folding beam phononic crystal (TFBPC) and its complementary structure. The dispersion curve relationships, transmission spectra and displacement fields of the eigenmodes are studied with FEA in detail. Compared with the traditional three layer phononic crystal (PC) structure, this structure proposed in this paper not only unfold bandgaps (BGs) in lower frequency range (below 300 Hz), but also has lighter weight because of beam structural cracks. We analyze the relevant physical mechanism behind this phenomenon, and discuss the effects of the tetragonal folding beam geometric parameters on band structure maps. FEM proves that the multi-cell structures with different arrangements have different acoustic BGs when compared with single cell structure. Harmonic frequency response and piezoelectric properties of TFBPC are specifically analyzed. The results confirm that this structure does have the recovery ability for low frequency vibration energy in environment. These conclusions in this paper could be indispensable to PC practical applications such as BG tuning and could be applied in portable devices, wireless sensor, micro-electro mechanical systems which can recycle energy from vibration environment as its own energy supply.

  3. BEAMING AND RAPID VARIABILITY OF HIGH-ENERGY RADIATION FROM RELATIVISTIC PAIR PLASMA RECONNECTION

    SciTech Connect

    Cerutti, B.; Werner, G. R.; Uzdensky, D. A.; Begelman, M. C. E-mail: greg.werner@colorado.edu E-mail: mitch@jila.colorado.edu

    2012-08-01

    We report on the first study of the angular distribution of energetic particles and radiation generated in relativistic collisionless electron-positron pair plasma reconnection using two-dimensional particle-in-cell simulations. We discover a strong anisotropy of the particles accelerated by reconnection and the associated strong beaming of their radiation. The focusing of particles and radiation increases with their energy; in this sense, this 'kinetic beaming' effect differs fundamentally from the relativistic Doppler beaming usually invoked in high-energy astrophysics, in which all photons are focused and boosted achromatically. We also present, for the first time, the modeling of the synchrotron emission as seen by an external observer during the reconnection process. The expected light curves comprise several bright symmetric sub-flares emitted by the energetic beam of particles sweeping across the line of sight intermittently, and exhibit super-fast time variability as short as about one-tenth of the system light-crossing time. The concentration of the energetic particles into compact regions inside magnetic islands and particle anisotropy explain the rapid variability. This radiative signature of reconnection can account for the brightness and variability of the gamma-ray flares in the Crab Nebula and in blazars.

  4. Broadband performance of a piezoelectric energy harvester based on the internal resonance of buckled beam

    NASA Astrophysics Data System (ADS)

    Xiong, Liuyang; Tang, Lihua; Ding, Hu; Chen, Liqun; Mace, Brian

    2016-04-01

    Nonlinear internal resonance mechanism is exploited in piezoelectric vibration energy harvesting (PVEH) for the purpose of broadening the resonance band. Conventional linear energy harvester has narrow operating bandwidth. In this research, a buckled piezoelectric beam structure with preload under transverse excitation is investigated to demonstrate the superiority of internal resonance. The condition for 2:1 internal resonance could be established by truncating the continuum beam with geometrical nonlinearity. Integro-partial-differential equations are derived for governing transverse motion measured from a stable equilibrium position. At specific initial axial compressive force, two modes are coupled through the internal resonance interaction. For weak nonlinear perturbations, multiple scales method is used to explore the amplitude-frequency responses of the buckled beam system under primary resonance with 2:1 internal resonance. Numerical examples demonstrate that the resonance bandwidth is broadened thanks to the coexistence of softening and hardening nonlinear characteristics. Moreover, validity of the approximate analytical method is demonstrated by comparing with simulation. Furthermore, the optimal resistance is discussed with a pure resistive load. This research on the internal resonance of buckled beam provides a basis for structure design and optimization in broadband PVEH.

  5. Studying astrophysical reactions with low-energy RI beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hayakawa, S.; Sakaguchi, Y.; Wakabayashi, Y.; Hashimoto, T.; Cherubini, S.; Gulino, M.; Spitaleri, C.; Rapisarda, G. G.; La Cognata, M.; Lamia, L.; Romano, S.; Kubono, S.; Iwasa, N.; Teranishi, T.; Kawabata, T.; Kwon, Y. K.; Binh, D. N.; Khiem, L. H.; Duy, N. N.; Kato, S.; Komatsubara, T.; Coc, A.; De Sereville, N.; Hammache, F.; Kiss, G.; Bishop, S.

    2016-05-01

    Studies on nuclear astrophysics, nuclear structure, and other interests have been performed using the radioactive-isotope (RI) beams at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study (CNS), the University of Tokyo. A typical measurement performed at CRIB is the elastic resonant scattering with the inverse kinematics. One recent experiment was on the α resonant scattering with 7Li and 7Be beams. This study is related to the astrophysical 7Li/7Be(α,γ) reactions, important at hot p-p chain and νp-process in supernovae. There have also been measurements based on other experimental methods. The first THM measurement using an RI beam has been performed at CRIB, to study the 18F(p, α)15O reaction at astrophysical energies via the three body reaction 2H(18F, α15O)n. The 18F(p, α) 15O reaction rate is crucial to understand the 511-keV γ-ray production in nova explosion phenomena, and we successfully evaluated the reaction cross section at novae temperature and below experimentally for the first time.

  6. Measuring linac photon beam energy through EPID image analysis of physically wedged fields

    SciTech Connect

    Dawoud, S. M. Weston, S. J.; Bond, I.; Ward, G. C.; Rixham, P. A.; Mason, J.; Huckle, A.; Sykes, J. R.

    2014-02-15

    Purpose: Electronic portal imaging devices (EPIDs) have proven to be useful tools for measuring several parameters of interest in linac quality assurance (QA). However, a method for measuring linac photon beam energy using EPIDs has not previously been reported. In this report, such a method is devised and tested, based on fitting a second order polynomial to the profiles of physically wedged beams, where the metric of interest is the second order coefficientα. The relationship between α and the beam quality index [percentage depth dose at 10 cm depth (PDD{sub 10})] is examined to produce a suitable calibration curve between these two parameters. Methods: Measurements were taken in a water-tank for beams with a range of energies representative of the local QA tolerances about the nominal value 6 MV. In each case, the beam quality was found in terms of PDD{sub 10} for 100 × 100 mm{sup 2} square fields. EPID images of 200 × 200 mm{sup 2} wedged fields were then taken for each beam and the wedge profile was fitted in MATLAB 2010b (The MathWorks, Inc., Natick, MA). α was then plotted against PDD{sub 10} and fitted with a linear relation to produce the calibration curve. The uncertainty in α was evaluated by taking five repeat EPID images of the wedged field for a beam of 6 MV nominal energy. The consistency of measuring α was found by taking repeat measurements on a single linac over a three month period. The method was also tested at 10 MV by repeating the water-tank crosscalibration for a range of energies centered approximately about a 10 MV nominal value. Finally, the calibration curve from the test linac and that from a separate clinical machine were compared to test consistency of the method across machines in a matched fleet. Results: The relationship betweenα and PDD{sub 10} was found to be strongly linear (R{sup 2} = 0.979) while the uncertainty in α was found to be negligible compared to that associated with measuring PDD{sub 10} in the water-tank (

  7. Simulation studies for operating electron beam ion trap at very low energy for disentangling edge plasma spectra

    SciTech Connect

    Jin Xuelong; Fei Zejie; Xiao Jun; Lu Di; Hutton, Roger; Zou Yaming

    2012-07-15

    Electron beam ion traps (EBITs) are very useful tools for disentanglement studies of atomic processes in plasmas. In order to assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. In this work, simulation studies for factors which hinder an EBIT to operate at very low electron energies were made based on the Tricomp (Field Precision) codes. Longitudinal, transversal, and total kinetic energy distributions were analyzed for all the electron trajectories. Influences from the electron current and electron energy on the energy depression caused by the space charge are discussed. The simulation results show that although the energy depression is most serious along the center of the electron beam, the electrons in the outer part of the beam are more likely to be lost when an EBIT is running at very low energy. Using the simulation results to guide us, we successfully managed to reach the minimum electron beam energy of 60 eV with a beam transmission above 57% for the SH-PermEBIT. Ar and W spectra were measured from the SH-PermEBIT at the apparent electron beam energies (read from the voltage difference between the electron gun cathode and the central drift tube) of 60 eV and 1200 eV, respectively. The spectra are shown in this paper.

  8. Simulation studies for operating electron beam ion trap at very low energy for disentangling edge plasma spectra

    NASA Astrophysics Data System (ADS)

    Jin, Xuelong; Fei, Zejie; Xiao, Jun; Lu, Di; Hutton, Roger; Zou, Yaming

    2012-07-01

    Electron beam ion traps (EBITs) are very useful tools for disentanglement studies of atomic processes in plasmas. In order to assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. In this work, simulation studies for factors which hinder an EBIT to operate at very low electron energies were made based on the Tricomp (Field Precision) codes. Longitudinal, transversal, and total kinetic energy distributions were analyzed for all the electron trajectories. Influences from the electron current and electron energy on the energy depression caused by the space charge are discussed. The simulation results show that although the energy depression is most serious along the center of the electron beam, the electrons in the outer part of the beam are more likely to be lost when an EBIT is running at very low energy. Using the simulation results to guide us, we successfully managed to reach the minimum electron beam energy of 60 eV with a beam transmission above 57% for the SH-PermEBIT. Ar and W spectra were measured from the SH-PermEBIT at the apparent electron beam energies (read from the voltage difference between the electron gun cathode and the central drift tube) of 60 eV and 1200 eV, respectively. The spectra are shown in this paper.

  9. Reconstructing supernova-neutrino spectra using low-energy beta beams.

    PubMed

    Jachowicz, N; McLaughlin, G C

    2006-05-01

    Neutrinos are the principal messengers reaching us from the center of a supernova. Terrestrial neutrino telescopes can provide precious information about the processes in the core of the star. But the information that a neutrino detector can supply is restricted by the fact that little experimental data on the neutrino-nucleus cross sections exist and by the uncertainties in theoretical calculations. In this Letter, we propose a novel procedure that determines the response of a target nucleus in a supernova-neutrino detector, by using low-energy beta beams. We show that fitting "synthetic" spectra, constructed by taking linear combinations of beta-beam spectra, to the original supernova-neutrino spectra reproduces the folded differential cross sections very accurately. Comparing the response in a detector to these synthetic responses provides a direct way to determine the main parameters of the supernova-neutrino energy distribution.

  10. Energy harvesting by dynamic unstability and internal resonance for piezoelectric beam

    SciTech Connect

    Lan, Chunbo; Qin, Weiyang Deng, Wangzheng

    2015-08-31

    We investigated the energy harvesting of a vertical beam with tip mass under vertical excitations. We applied dynamic unstability and internal resonance to improve the efficiency of harvesting. The experiments of harmonic excitation were carried out. Results show that for the beam there exist internal resonances in the dynamically unstable and the buckling bistable cases. The dynamic unstability is a determinant for strong internal resonance or mode coupling, which can be used to create a large output from piezoelectric patches. Then, the experiments of stochastic excitation were carried out. Results prove that the internal resonance or mode coupling can transfer the excitation energy to the low order modes, mainly the first and the second one. This can bring about a large output voltage. For a stochastic excitation, it is proved that there is an optimal weight of tip mass for realizing internal resonance and producing large outputs.

  11. Ion Beam Heated Target Simulations for Warm Dense Matter Physics and Inertial Fusion Energy

    SciTech Connect

    Barnard, J J; Armijo, J; Bailey, D S; Friedman, A; Bieniosek, F M; Henestroza, E; Kaganovich, I; Leung, P T; Logan, B G; Marinak, M M; More, R M; Ng, S F; Penn, G E; Perkins, L J; Veitzer, S; Wurtele, J S; Yu, S S; Zylstra, A B

    2008-08-12

    Hydrodynamic simulations have been carried out using the multi-physics radiation hydrodynamics code HYDRA and the simplified one-dimensional hydrodynamics code DISH. We simulate possible targets for a near-term experiment at LBNL (the Neutralized Drift Compression Experiment, NDCX) and possible later experiments on a proposed facility (NDCX-II) for studies of warm dense matter and inertial fusion energy related beam-target coupling. Simulations of various target materials (including solids and foams) are presented. Experimental configurations include single pulse planar metallic solid and foam foils. Concepts for double-pulsed and ramped-energy pulses on cryogenic targets and foams have been simulated for exploring direct drive beam target coupling, and concepts and simulations for collapsing cylindrical and spherical bubbles to enhance temperature and pressure for warm dense matter studies are described.

  12. ION BEAM HEATED TARGET SIMULATIONS FOR WARM DENSE MATTER PHYSICS AND INERTIAL FUSION ENERGY

    SciTech Connect

    Barnard, J.J.; Armijo, J.; Bailey, D.S.; Friedman, A.; Bieniosek, F.M.; Henestroza, E.; Kaganovich, I.; Leung, P.T.; Logan, B.G.; Marinak, M.M.; More, R.M.; Ng, S.F.; Penn, G.E.; Perkins, L.J.; Veitzer, S.; Wurtele, J.S.; Yu, S.S.; Zylstra, A.B.

    2008-08-01

    Hydrodynamic simulations have been carried out using the multi-physics radiation hydrodynamics code HYDRA and the simplified one-dimensional hydrodynamics code DISH. We simulate possible targets for a near-term experiment at LBNL (the Neutralized Drift Compression Experiment, NDCX) and possible later experiments on a proposed facility (NDCX-II) for studies of warm dense matter and inertial fusion energy related beam-target coupling. Simulations of various target materials (including solids and foams) are presented. Experimental configurations include single pulse planar metallic solid and foam foils. Concepts for double-pulsed and ramped-energy pulses on cryogenic targets and foams have been simulated for exploring direct drive beam target coupling, and concepts and simulations for collapsing cylindrical and spherical bubbles to enhance temperature and pressure for warm dense matter studies are described.

  13. Wall-plug efficiency and beam dynamics in free-electron lasers using energy recovery linacs

    SciTech Connect

    Sprangle, P.; Ben-Zvi, I.; Penano, J.; Hafizi, B.

    2010-08-01

    In a high average power free-electron laser (FEL) the wall-plug efficiency is of critical importance in determining the size, complexity, and cost of the overall system. The wall-plug efficiency for the FEL oscillator and amplifier (uniform and tapered wiggler) is strongly dependent on the energy recovery process. A theoretical model for electron beam dynamics in the energy recovery linac is derived and applied to the acceleration and deceleration of nano-Coulomb electron bunches for a tapered FEL amplifier. For the tapered amplifier, the spent electron beam exiting the wiggler consists of trapped and untrapped electrons. Decelerating these two populations using different phases of the radio-frequency wave in the recovery process enhances wall-plug efficiency. For the parameters considered here, the wall-plug efficiency for the tapered amplifier can be {approx}10% using this approach.

  14. Beam Energy Scan of Specific Heat Through Temperature Fluctuations in Heavy Ion Collisions

    NASA Astrophysics Data System (ADS)

    Basu, Sumit; Nandi, Basanta K.; Chatterjee, Sandeep; Chatterjee, Rupa; Nayak, Tapan

    2016-01-01

    Temperature fluctuations may have two distinct origins, first, quantum fluctuations that are initial state fluctuations, and second, thermodynamical fluctuations. We discuss a method of extracting the thermodynamic temperature from the mean transverse momentum of pions, by using controllable parameters such as centrality of the system, and range of the transverse momenta. Event-by-event fluctuations in global temperature over a large phase space provide the specific heat of the system. We present Beam Energy Scan of specific heat from data, AMPT and HRG model prediction. Experimental results from NA49, STAR, PHENIX, PHOBOS and ALICE are combined to obtain the specific heat as a function of beam energy. These results are compared to calculations from AMPT event generator, HRG model and lattice calculations, respectively.

  15. MINOS+: a Proposal to FNAL to run MINOS with the medium energy NuMI beam

    SciTech Connect

    Tzanankos, G.; Bishai, M.; Diwan, M.; Escobar, C.O.; Gomes, R.A.; Gouffon, P.; Blake, A.; Thomson, M.; Patterson, R.B.; Adamson, P.; Childress, S.; /Fermilab /IIT, Chicago /Los Alamos /Minnesota U. /Minnesota U., Duluth /Bhubaneswar, NISER /Iowa State U.

    2011-05-01

    This is a proposal to continue to expose the two MINOS detectors to the NuMI muon neutrino beam for three years starting in 2013. The medium energy setting of the NuMI beam projected for NO{nu}A will deliver about 18 x 10{sup 20} protons-on-target during the first three years of operation. This will allow the MINOS Far Detector to collect more than 10,000 charged current muon neutrino events in the 4-10 GeV energy range and provide a stringent test for non-standard neutrino interactions, sterile neutrinos, extra dimensions, neutrino time-of-flight, and perhaps more. In addition there will be more than 3,000 neutral current events which will be particularly useful in extending the sterile neutrino search range.

  16. Production of low axial energy spread ion beams with multicusp sources

    SciTech Connect

    Lee, Y.H.Y.

    1998-05-01

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  17. Low energy highly charged ion beam facility at Inter University Accelerator Centre: Measurement of the plasma potential and ion energy distributions

    SciTech Connect

    Sairam, T. Bhatt, Pragya; Safvan, C. P.; Kumar, Ajit; Kumar, Herendra

    2015-11-15

    A deceleration lens coupled to one of the beam lines of the electron cyclotron resonance based low energy beam facility at Inter University Accelerator Centre is reported. This system is capable of delivering low energy (2.5 eV/q–1 keV/q) highly charged ion beams. The presence of plasma potential hinders the measurements of low energies (<50 eV), therefore, plasma potential measurements have been undertaken using a retarding plate analyzer in unison with the deceleration assembly. The distributions of the ion energies have been obtained and the effect of different source parameters on these distributions is studied.

  18. Nuclear Astrophysics Programs with Low-Energy RI Beams at CRIB

    SciTech Connect

    Kubono, S.; Binh, Dam N.; Hayakawa, S.; Hashimoto, T.; Kahl, D. M.; Yamaguchi, H.; Wakabayashi, Y.; Teranishi, T.; Iwasa, N.; Komatsubara, T.; Kato, S.; Khiem, Le H.

    2010-04-30

    Nuclear astrophysics activities with CNS RI beam separator (CRIB) are reported together with the present status of the CRIB facility which is supported by the AVF upgrade project for the total development of the low-energy RIB facility. The activities include direct and indirect measurements of stellar reactions especially relevant to explosive burning processes such as nova and supernovae. Some recent results are discussed together with a scope of the facility.

  19. Nuclear Astrophysics Programs with Low-Energy RI Beams at CRIB

    NASA Astrophysics Data System (ADS)

    Kubono, S.; Binh, Dam N.; Hayakawa, S.; Hashimoto, T.; Kahl, D. M.; Yamaguchi, H.; Wakabayashi, Y.; Teranishi, T.; Iwasa, N.; Komatsubara, T.; Kato, S.; Khiem, Le H.

    2010-04-01

    Nuclear astrophysics activities with CNS RI beam separator (CRIB) are reported together with the present status of the CRIB facility which is supported by the AVF upgrade project for the total development of the low-energy RIB facility. The activities include direct and indirect measurements of stellar reactions especially relevant to explosive burning processes such as nova and supernovae. Some recent results are discussed together with a scope of the facility.

  20. Photonuclear dose calculations for high-energy photon beams from Siemens and Varian linacs.

    PubMed

    Chibani, Omar; Ma, Chang-Ming Charlie

    2003-08-01

    The dose from photon-induced nuclear particles (neutrons, protons, and alpha particles) generated by high-energy photon beams from medical linacs is investigated. Monte Carlo calculations using the MCNPX code are performed for three different photon beams from two different machines: Siemens 18 MV, Varian 15 MV, and Varian 18 MV. The linac head components are simulated in detail. The dose distributions from photons, neutrons, protons, and alpha particles are calculated in a tissue-equivalent phantom. Neutrons are generated in both the linac head and the phantom. This study includes (a) field size effects, (b) off-axis dose profiles, (c) neutron contribution from the linac head, (d) dose contribution from capture gamma rays, (e) phantom heterogeneity effects, and (f) effects of primary electron energy shift. Results are presented in terms of absolute dose distributions and also in terms of DER (dose equivalent ratio). The DER is the maximum dose from the particle (neutron, proton, or alpha) divided by the maximum photon dose, multiplied by the particle quality factor and the modulation scaling factor. The total DER including neutrons, protons, and alphas is about 0.66 cSv/Gy for the Siemens 18 MV beam (10 cm x 10 cm). The neutron DER decreases with decreasing field size while the proton (or alpha) DER does not vary significantly except for the 1 cm x 1 cm field. Both Varian beams (15 and 18 MV) produce more neutrons, protons, and alphas particles than the Siemens 18 MV beam. This is mainly due to their higher primary electron energies: 15 and 18.3 MeV, respectively, vs 14 MeV for the Siemens 18 MV beam. For all beams, neutrons contribute more than 75% of the total DER, except for the 1 cm x 1 cm field (approximately 50%). The total DER is 1.52 and 2.86 cSv/Gy for the 15 and 18 MV Varian beams (10 cm x 10 cm), respectively. Media with relatively high-Z elements like bone may increase the dose from heavy charged particles by a factor 4. The total DER is sensitive to