Science.gov

Sample records for high-intensity high-energy proton

  1. Dynamics of high-energy proton beam acceleration and focusing from hemisphere-cone targets by high-intensity lasers.

    PubMed

    Qiao, B; Foord, M E; Wei, M S; Stephens, R B; Key, M H; McLean, H; Patel, P K; Beg, F N

    2013-01-01

    Acceleration and focusing of high-energy proton beams from fast-ignition (FI) -related hemisphere-cone assembled targets have been numerically studied by hybrid particle-in-cell simulations and compared with those from planar-foil and open-hemisphere targets. The whole physical process including the laser-plasma interaction has been self-consistently modeled for 15 ps, at which time the protons reach asymptotic motion. It is found that the achievable focus of proton beams is limited by the thermal pressure gradients in the co-moving hot electrons, which induce a transverse defocusing electric field that bends proton trajectories near the axis. For the advanced hemisphere-cone target, the flow of hot electrons along the cone wall induces a local transverse focusing sheath field, resulting in a clear enhancement in proton focusing; however, it leads to a significant loss of longitudinal sheath potential, reducing the total conversion efficiency from laser to protons. PMID:23410447

  2. Impact of high energy high intensity proton beams on targets: Case studies for Super Proton Synchrotron and Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Tahir, N. A.; Sancho, J. Blanco; Shutov, A.; Schmidt, R.; Piriz, A. R.

    2012-05-01

    The Large Hadron Collider (LHC) is designed to collide two proton beams with unprecedented particle energy of 7 TeV. Each beam comprises 2808 bunches and the separation between two neighboring bunches is 25 ns. The energy stored in each beam is 362 MJ, sufficient to melt 500 kg copper. Safety of operation is very important when working with such powerful beams. An accidental release of even a very small fraction of the beam energy can result in severe damage to the equipment. The machine protection system is essential to handle all types of possible accidental hazards; however, it is important to know about possible consequences of failures. One of the critical failure scenarios is when the entire beam is lost at a single point. In this paper we present detailed numerical simulations of the full impact of one LHC beam on a cylindrical solid carbon target. First, the energy deposition by the protons is calculated with the FLUKA code and this energy deposition is used in the BIG2 code to study the corresponding thermodynamic and the hydrodynamic response of the target that leads to a reduction in the density. The modified density distribution is used in FLUKA to calculate new energy loss distribution and the two codes are thus run iteratively. A suitable iteration step is considered to be the time interval during which the target density along the axis decreases by 15%-20%. Our simulations suggest that the full LHC proton beam penetrates up to 25 m in solid carbon whereas the range of the shower from a single proton in solid carbon is just about 3 m (hydrodynamic tunneling effect). It is planned to perform experiments at the experimental facility HiRadMat (High Radiation Materials) at CERN using the proton beam from the Super Proton Synchrotron (SPS), to compare experimental results with the theoretical predictions. Therefore simulations of the response of a solid copper cylindrical target hit by the SPS beam were performed. The particle energy in the SPS beam is 440

  3. High intensity proton synchrotrons

    NASA Astrophysics Data System (ADS)

    Craddock, M. K.

    1986-10-01

    Strong initiatives are being pursued in a number of countries for the construction of ``kaon factory'' synchrotrons capable of producing 100 times more intense proton beams than those available now from machines such as the Brookhaven AGS and CERN PS. Such machines would yield equivalent increases in the fluxes of secondary particles (kaons, pions, muons, antiprotons, hyperons and neutrinos of all varieties)—or cleaner beams for a smaller increase in flux—opening new avenues to various fundamental questions in both particle and nuclear physics. Major areas of investigation would be rare decay modes, CP violation, meson and hadron spectroscopy, antinucleon interactions, neutrino scattering and oscillations, and hypernuclear properties. Experience with the pion factories has already shown how high beam intensities make it possible to explore the ``precision frontier'' with results complementary to those achievable at the ``energy frontier''. This paper will describe proposals for upgrading and AGS and for building kaon factories in Canada, Europe, Japan and the United States, emphasizing the novel aspects of accelerator design required to achieve the desired performance (typically 100 μA at 30 GeV).

  4. High intensity protons in RHIC

    SciTech Connect

    Montag, C.; Ahrens, L.; Blaskiewicz, M.; Brennan, J. M.; Drees, K. A.; Fischer, W.; Huang, H.; Minty, M.; Robert-Demolaize, G.; Thieberger, P.; Yip, K.

    2012-01-05

    During the 2012 summer shutdown a pair of electron lenses will be installed in RHIC, allowing the beam-beam parameter to be increased by roughly 50 percent. To realize the corresponding luminosity increase bunch intensities have to be increased by 50 percent, to 2.5 {center_dot} 10{sup 11} protons per bunch. We list the various RHIC subsystems that are most affected by this increase, and propose beam studies to ensure their readiness. The proton luminosity in RHIC is presently limited by the beam-beam effect. To overcome this limitation, electron lenses will be installed in IR10. With the help of these devices, the headon beam-beam kick experienced during proton-proton collisions will be partially compensated, allowing for a larger beam-beam tuneshift at these collision points, and therefore increasing the luminosity. This will be accomplished by increasing the proton bunch intensity from the presently achieved 1.65 {center_dot} 10{sup 11} protons per bunch in 109 bunches per beam to 2.5 {center_dot} 10{sup 11}, thus roughly doubling the luminosity. In a further upgrade we aim for bunch intensities up to 3 {center_dot} 10{sup 11} protons per bunch. With RHIC originally being designed for a bunch intensity of 1 {center_dot} 10{sup 11} protons per bunch in 56 bunches, this six-fold increase in the total beam intensity by far exceeds the design parameters of the machine, and therefore potentially of its subsystems. In this note, we present a list of major subsystems that are of potential concern regarding this intensity upgrade, show their demonstrated performance at present intensities, and propose measures and beam experiments to study their readiness for the projected future intensities.

  5. Applications of High Intensity Proton Accelerators

    NASA Astrophysics Data System (ADS)

    Raja, Rajendran; Mishra, Shekhar

    2010-06-01

    collider and neutrino factory - summary of working group 2 / J. Galambos, R. Garoby and S. Geer -- Prospects for a very high power CW SRF linac / R. A. Rimmer -- Indian accelerator program for ADS applications / V. C. Sahni and P. Singh -- Ion accelerator activities at VECC (particularly, operating at low temperature) / R. K. Bhandari -- Chinese efforts in high intensity proton accelerators / S. Fu, J. Wang and S. Fang -- ADSR activity in the UK / R. J. Barlow -- ADS development in Japan / K. Kikuchi -- Project-X, SRF, and very large power stations / C. M. Ankenbrandt, R. P. Johnson and M. Popovic -- Power production and ADS / R. Raja -- Experimental neutron source facility based on accelerator driven system / Y. Gohar -- Transmutation mission / W. S. Yang -- Safety performance and issues / J. E. Cahalan -- Spallation target design for accelerator-driven systems / Y. Gohar -- Design considerations for accelerator transmutation of waste system / W. S. Yang -- Japan ADS program / T. Sasa -- Overview of members states' and IAEA activities in the field of Accelerator Driven Systems (ADS) / A. Stanculescu -- Linac for ADS applications - accelerator technologies / R. W. Garnett and R. L. Sheffield -- SRF linacs and accelerator driven sub-critical systems - summary working groups 3 & 4 / J. Delayen -- Production of Actinium-225 via high energy proton induced spallation of Thorium-232 / J. Harvey ... [et al.] -- Search for the electric dipole moment of Radium-225 / R. J. Holt, Z.-T. Lu and R. Mueller -- SRF linac and material science and medicine - summary of working group 5 / J. Nolen, E. Pitcher and H. Kirk.

  6. High-Intensity Proton Accelerator

    SciTech Connect

    Jay L. Hirshfield

    2011-12-27

    Analysis is presented for an eight-cavity proton cyclotron accelerator that could have advantages as compared with other accelerators because of its potentially high acceleration gradient. The high gradient is possible since protons orbit in a sequence of TE111 rotating mode cavities of equally diminishing frequencies with path lengths during acceleration that greatly exceed the cavity lengths. As the cavities operate at sequential harmonics of a basic repetition frequency, phase synchronism can be maintained over a relatively wide injection phase window without undue beam emittance growth. It is shown that use of radial vanes can allow cavity designs with significantly smaller radii, as compared with simple cylindrical cavities. Preliminary beam transport studies show that acceptable extraction and focusing of a proton beam after cyclic motion in this accelerator should be possible. Progress is also reported on design and tests of a four-cavity electron counterpart accelerator for experiments to study effects on beam quality arising from variations injection phase window width. This device is powered by four 500-MW pulsed amplifiers at 1500, 1800, 2100, and 2400 MHz that provide phase synchronous outputs, since they are driven from a with harmonics derived from a phase-locked 300 MHz source.

  7. Magnets for high intensity proton synchrotrons

    SciTech Connect

    Jean-Francois Ostiguy, Vladimir Kashikhine and Alexander Makarov

    2002-09-19

    Recently, there has been considerable interest at Fermilab for the Proton Driver, a future high intensity proton machine. Various scenarios are under consideration, including a superconducting linac. Each scenario present some special challenges. We describe here the magnets proposed in a recent study, the Proton Driver Study II, which assumes a conventional warm synchrotron, roughly of the size of the existing FNAL booster, but capable of delivering 380 kW at 8 GeV.

  8. CW high intensity non-scaling FFAG proton drivers

    SciTech Connect

    Johnstone, C.; Berz, M.; Makino, K.; Snopok, P.; /IIT, Chicago

    2011-04-01

    Accelerators are playing increasingly important roles in basic science, technology, and medicine including nuclear power, industrial irradiation, material science, and neutrino production. Proton and light-ion accelerators in particular have many research, energy and medical applications, providing one of the most effective treatments for many types of cancer. Ultra high-intensity and high-energy (GeV) proton drivers are a critical technology for accelerator-driven sub-critical reactors (ADS) and many HEP programs (Muon Collider). These high-intensity GeV-range proton drivers are particularly challenging, encountering duty cycle and space-charge limits in the synchrotron and machine size concerns in the weaker-focusing cyclotrons; a 10-20 MW proton driver is not presently considered technically achievable with conventional re-circulating accelerators. One, as-yet, unexplored re-circulating accelerator, the Fixed-field Alternating Gradient, or FFAG, is an attractive alternative to the cyclotron. Its strong focusing optics are expected to mitigate space charge effects, and a recent innovation in design has coupled stable tunes with isochronous orbits, making the FFAG capable of fixed-frequency, CW acceleration, as in the classical cyclotron. This paper reports on these new advances in FFAG accelerator technology and references advanced modeling tools for fixed-field accelerators developed for and unique to the code COSY INFINITY.

  9. Periods of High Intensity Solar Proton Flux

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael A.; Stauffer, Craig A.; Jordan, Thomas M.; Adams, James H.; Dietrich, William F.

    2012-01-01

    Analysis is presented for times during a space mission that specified solar proton flux levels are exceeded. This includes both total time and continuous time periods during missions. Results for the solar maximum and solar minimum phases of the solar cycle are presented and compared for a broad range of proton energies and shielding levels. This type of approach is more amenable to reliability analysis for spacecraft systems and instrumentation than standard statistical models.

  10. ELECTRON CLOUD EFFECTS IN HIGH INTENSITY PROTON ACCELERATORS.

    SciTech Connect

    WEI,J.; MACEK,R.J.

    2002-04-14

    One of the primary concerns in the design and operation of high-intensity proton synchrotrons and accumulators is the electron cloud and associated beam loss and instabilities. Electron-cloud effects are observed at high-intensity proton machines like the Los Alamos National Laboratory's PSR and CERN's SPS, and investigated experimentally and theoretically. In the design of next-generation high-intensity proton accelerators like the Spallation Neutron Source ring, emphasis is made in minimizing electron production and in enhancing Landau damping. This paper reviews the present understanding of the electron-cloud effects and presents mitigation measures.

  11. Proton shock acceleration using a high contrast high intensity laser

    NASA Astrophysics Data System (ADS)

    Gauthier, Maxence; Roedel, Christian; Kim, Jongjin; Aurand, Bastian; Curry, Chandra; Goede, Sebastian; Propp, Adrienne; Goyon, Clement; Pak, Art; Kerr, Shaun; Ramakrishna, Bhuvanesh; Ruby, John; William, Jackson; Glenzer, Siegfried

    2015-11-01

    Laser-driven proton acceleration is a field of intense research due to the interesting characteristics of this novel particle source including high brightness, high maximum energy, high laminarity, and short duration. Although the ion beam characteristics are promising for many future applications, such as in the medical field or hybrid accelerators, the ion beam generated using TNSA, the acceleration mechanism commonly achieved, still need to be significantly improved. Several new alternative mechanisms have been proposed such as collisionless shock acceleration (CSA) in order to produce a mono-energetic ion beam favorable for those applications. We report the first results of an experiment performed with the TITAN laser system (JLF, LLNL) dedicated to the study of CSA using a high intensity (5x1019W/cm2) high contrast ps laser pulse focused on 55 μm thick CH and CD targets. We show that the proton spectrum generated during the interaction exhibits high-energy mono-energetic features along the laser axis, characteristic of a shock mechanism.

  12. Critical design issues of high intensity proton linacs

    SciTech Connect

    Lawrence, G.P.

    1994-08-01

    Medium-energy proton linear accelerators are being studied as drivers for spallation applications requiring large amounts of beam powder. Important design factors for such high-intensity linacs are reviewed, and issues and concerns specific to this unprecedented power regime are discussed.

  13. PULSED POWER APPLICATIONS IN HIGH INTENSITY PROTON RINGS.

    SciTech Connect

    ZHANG, S.Y.; SANDBERG, J.; ET AL.

    2005-05-16

    Pulsed power technology has been applied in particle accelerators and storage rings for over four decades. It is most commonly used in injection, extraction, beam manipulation, source, and focusing systems. These systems belong to the class of repetitive pulsed power. In this presentation, we review and discuss the history, present status, and future challenge of pulsed power applications in high intensity proton accelerators and storage rings.

  14. STATUS OF SLOW EXTRACTION OF HIGH INTENSITY PROTONS FROM BROOKHAVEN'S AGS.

    SciTech Connect

    BROWN,K.A.AHRENS,L.BRENNAN,J.M.GLENN,J.W.ROSER,T.RUSSO,T.TSOUPAS,N.SMITH,K.ZENO,K.

    2003-05-12

    The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7 x 10{sup 13} protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams. We have an active program of high energy physics experiments, including the high precision measurement of the muons magnetic moment [1] and the discovery of the rare Kaon decay, K+ {yields} {pi} + {nu}{bar {nu}} [2]. This program is continuing into the future with the rare symmetry violating process experiments [3] currently being designed to operate at the AGS. In this paper, we will present results from operation of high intensity slow extraction, the problems we encounter, and our solutions to those problems.

  15. Report of the Snowmass M6 Working Group on high intensity proton sources

    SciTech Connect

    Weiren Chou and J. Wei

    2002-08-20

    The U.S. high-energy physics program needs an intense proton source, a 1-4 MW Proton Driver (PD), by the end of this decade. This machine will serve as a stand-alone facility that will provide neutrino superbeams and other high intensity secondary beams such as kaons, muons, neutrons, and anti-protons (cf. E1 and E5 group reports) and also serve as the first stage of a neutrino factory (cf. M1 group report). It can also be a high brightness source for a VLHC. Based on present accelerator technology and project construction experience, it is both feasible and cost-effective to construct a 1-4 MW Proton Driver. Two recent PD design studies have been made, one at FNAL and the other at the BNL. Both designed PD's for 1 MW proton beams at a cost of about U.S. $200M (excluding contingency and overhead) and both designs were upgradeable to 4 MW. An international collaboration between FNAL, BNL and KEK on high intensity proton facilities is addressing a number of key design issues. The superconducting (sc) RF cavities, cryogenics, and RF controls developed for the SNS can be directly adopted to save R&D efforts, cost, and schedule. PD studies are also actively being pursued at Europe and Japan.

  16. REPORT OF THE SNOWMASS M6 WORKING GROUP ON HIGH INTENSITY PROTON SOURCES.

    SciTech Connect

    CHOU,W.; WEI,J.

    2001-08-14

    The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade.

  17. Recent developments for high-intensity proton linacs

    SciTech Connect

    Wangler, T.P.; Garnett, R.W.; Gray, E.R.; Nath, S.

    1996-04-01

    High-intensity proton linacs are being proposed for new projects around the world, especially for tritium production, and for pulsed spallation neutron sources. Typical requirements for these linacs include peak beam current of about 100 mA, and final energies of 1 GeV and higher, APT, a tritium production linac, requires cw operation to obtain sufficient average tritium production linac, requires cw operation to obtain sufficient average beam power, and H{sup +} ion sources appear capable of providing the required current and emittances. The pulsed spallation neutron source requires a linac as an injector to one or more accumulator rings, and favors the use of an H{sup minus} beam to allow charge-exchange injection into the rings. For both applications high availability is demanded; the fraction of scheduled beam time for actual production must be 75% or more. Such a high availability requires low beam-loss to avoid radioactivation of the accelerator, and to allow hands-on maintenance that will keep the mean repair and maintenance times short. To keep the accelerator activation sufficiently low, the beam loss should not exceed about 0.1 to 1.0 nA/m, except perhaps for a few localized places, where special design adaptations could be made. The requirement of such small beam losses at such a high intensity presents a new beam physics challenge. This challenge will require greater understanding of the beam distribution, including the low- density beam halo, which is believed to be responsible for most of the beam losses. Furthermore, it will be necessary to choose the apertures so the beam losses will be acceptably low, and because large aperture size is generally accompanied by an economic penalty resulting from reduced power efficiency, an optimized choice of the aperture will be desirable.

  18. Liquid lithium target as a high intensity, high energy neutron source

    DOEpatents

    Parkin, Don M.; Dudey, Norman D.

    1976-01-01

    This invention provides a target jet for charged particles. In one embodiment the charged particles are high energy deuterons that bombard the target jet to produce high intensity, high energy neutrons. To this end, deuterons in a vacuum container bombard an endlessly circulating, free-falling, sheet-shaped, copiously flowing, liquid lithium jet that gushes by gravity from a rectangular cross-section vent on the inside of the container means to form a moving web in contact with the inside wall of the vacuum container. The neutrons are produced via break-up of the beam in the target by stripping, spallation and compound nuclear reactions in which the projectiles (deuterons) interact with the target (Li) to produce excited nuclei, which then "boil off" or evaporate a neutron.

  19. High Energy K(alpha) Radiography Using High-intensity, Short-pulse Lasers

    SciTech Connect

    Park, H; Izumi, N; Key, M H; King, J A; Koch, J A; Landen, O L; Patel, P K; Price, D F; Remington, B A; Robey, H F; Snavely, R A; Tabak, M; Town, R J; Wickersham, J E; Stoeckl, C; Storm, M; Theobald, W; Chambers, D M; Eagelton, R; Goldsack, T; Clarke, R J; Heathcote, R; Giraldez, E; Nikroo, A; Steinman, D A; Stephens, R B; Zhang, B B

    2005-11-16

    We have performed experiments using Callisto, the Vulcan 100 TW and the Vulcan Petawatt high intensity lasers to understand the characteristics of high energy, K{alpha} x-ray sources and to implement workable radiography solutions at 20-100 keV. Our measurements show that the K{alpha} size from a simple foil target is larger than 60 {micro}m, far larger than the experiment resolution requirement. The total K{alpha} yield is independent of target thicknesses verifying that refluxing plays a major role in photon generation. Smaller radiating volumes emit brighter K{alpha} radiation. 1-D radiography experiments using small-edge-on foils resolved 10 {micro}m features with high contrast. We tested a variety of small volume 2-D point sources such as cones, wires, and embedded wires, measuring photon yields and comparing our measurements with predictions from hybrid-PIC LSP simulations. In addition to high-energy, high-resolution backlighters, future experiments will also need imaging detectors and diagnostic tools that are workable in the 20-100 keV energy range. An initial look at some of these detector issues is also presented.

  20. Space-charge compensation in high-intensity proton rings

    SciTech Connect

    A. Burov, G.W. Foster and V.D. Shiltsev

    2000-09-21

    Recently, it was proposed to use negatively charged electron beams for compensation of beam-beam effects due to protons in the Tevatron collider. The authors show that a similar compensation is possible in space-charge dominated low energy proton beams. The idea has a potential of several-fold increase of the FNAL Booster beam brightness. Best results will be obtained using three electron lenses around the machine circumference, using co-moving electron beam with time structure and profile approximately matched to the proton beam. This technique, if feasible, will be more cost effective than the straightforward alternative of increasing the energy of the injection linac.

  1. Time Exceedances for High Intensity Solar Proton Fluxes

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael A.; Stauffer, Craig A.; Jordan, Thomas M.; Adam, James H., Jr.; Dietrich, William F.

    2011-01-01

    A model is presented for times during a space mission that specified solar proton flux levels are exceeded. This includes both total time and continuous time periods during missions. Results for the solar maximum and solar minimum phases of the solar cycle are presented and compared for a broad range of proton energies and shielding levels. This type of approach is more amenable to reliability analysis for spacecraft systems and instrumentation than standard statistical models.

  2. Generation of high-energy (>15 MeV) neutrons using short pulse high intensity lasers

    SciTech Connect

    Petrov, G. M.; Davis, J.; Petrova, Tz. B.; Higginson, D. P.; McNaney, J. M.; McGuffey, C.; Qiao, B.; Beg, F. N.

    2012-09-15

    A roadmap is suggested and demonstrated experimentally for the production of high-energy (>15 MeV) neutrons using short pulse lasers. Investigation with a 3D Monte Carlo model has been employed to quantify the production of energetic neutrons. Numerical simulations have been performed for three nuclear reactions, d(d,n){sup 3}He, {sup 7}Li(d,n){sup 8}Be, and {sup 7}Li(p,n){sup 7}Be, driven by monoenergetic ion beams. Quantitative estimates for the driver ion beam energy and number have been made and the neutron spectra and yield in the ion propagation direction have been evaluated for various incident ion energies. In order to generate neutron fluence above a detection limit of 10{sup 6} neutrons/sr, either {approx}10{sup 10} protons with energy 20-30 MeV or comparable amount of deuterons with energy 5-10 MeV are required. Experimental verification of the concept with deuterons driven by the Titan laser (peak intensity 2 Multiplication-Sign 10{sup 19} W/cm{sup 2}, pulse duration of 9 ps, wavelength 1.05 {mu}m, and energy of 360 J) is provided with the generation of neutrons with energy of up to 18 MeV from {sup 7}Li(d,n){sup 8}Be reactions. Future research will focus on optimized schemes for ion acceleration for production of high-energy neutrons, which will involve efficient target design, laser parameter optimization, and converter material.

  3. Acceleration of Ultra-Low Emittance Proton and Ion Beams with High Intensity Lasers

    NASA Astrophysics Data System (ADS)

    Cowan, Thomas E.

    2002-11-01

    Intense beams of several MeV protons and ions, generated by the interaction of high-intensity short pulse lasers with thin foils, have been observed by many researchers in recent years.(S.P. Hatchett et al., Phys. Plasmas 7, 2076 (2000); T.E. Cowan et al., Nucl. Inst. Meth. A 455, 130 (2000); R.A. Snavely et al., Phys. Rev. Lett. 85, 2945 (2000); S.C. Wilks et al., Phys. Plasmas 8, 532 (2000); E. Clark et al., Phys. Rev. Lett. 84, 670 (2000).) In experiments performed at the 100 TW LULI laser, we have succeeded to control the ion acceleration process to produce ultra high quality proton beams, whose transverse emittance is <0.006 π mm-mrad (rms-normalized), a factor of 100 lower than is typical of conventional RF linear accelerators. Within the envelope of the entire beam, we could focus individual proton beamlets to 100 nm spatial scales. This required control of the laser-plasma interaction, of the transport of MA currents of relativistic electrons through the target substrate, and of the surface topology and source material layering on the target foil rear-surface.(M. Roth et al., Phys. Rev. ST Accel. Beams 5, 061002 (2002).) By varying the source material, we also accelerated light ion beams, such as He-like fluorine, to over 5 MeV/nucleon.(M. Hegelich et al., Phys. Rev. Lett. 89, 085002 (2002).) From PIC simulations we understand the highest-energy and lowest-divergence proton acceleration as a transient laser-driven virtual cathode effect occurring at the target rear-surface. We have also confirmed the acceleration of ions from the front surface (A. Maksimchuk et al., Phys. Rev. Lett. 84, 4108 (2000).), which we find exhibits an intense low-energy component, but only a tenuous high-energy component, in agreement with PIC simulations. This work was performed with corporate support of General Atomics.

  4. FFAG-BASED HIGH-INTENSITY PROTON DRIVERS.

    SciTech Connect

    RUGGIERO, A.G.

    2004-10-13

    This paper is the summary of a feasibility study of a Fixed-Field Alternating-Gradient (FFAG) Accelerator for Protons in the one-to-few GeV energy range, and average beam power of several MWatt. The example they have adopted here is a beam energy of 1 GeV and an average power of 10 MWatt, but of course the same design approach can be used with other beam parameters. The design principles, merits and limitations of the FFAG accelerators have been described previously. In particular, more advanced techniques to minimize magnet dimension and field strength have been recently proposed. The design makes use of a novel concept by which it is possible to cancel chromatic effects, thus making betatron tunes and functions independent of the particle momentum, with an Adjusted Field Profile. The example given here assumes a pulsed mode of operation at the repetition rate of 1.0 kHz.

  5. H- Ion Sources for High Intensity Proton Drivers

    SciTech Connect

    Dudnikov, Vadim; Johnson, Rolland P.; Stockli, Martin P; Welton, Robert F; Dudnikova, Galina

    2010-01-01

    Spallation neutron source user facilities require reliable, intense beams of protons. The technique of H- charge exchange injection into a storage ring or synchrotron can provide the needed beam currents, but may be limited by the ion sources that have currents and reliability that do not meet future requirements and emittances that are too large for efficient acceleration. In this project we are developing an H- source which will synthesize the most important developments in the field of negative ion sources to provide high current, small emittance, good lifetime, high reliability, and power efficiency. We describe planned modifications to the present external antenna source at SNS that involve: 1) replacing the present 2 MHz plasma-forming solenoid antenna with a 60 MHz saddle-type antenna and 2) replacing the permanent multicusp magnet with a weaker electromagnet, in order to increase the plasma density near the outlet aperture. The SNS test stand will then be used to verify simulations of this approach that indicate significant improvements in H- output current and efficiency, where lower RF power will allow higher duty factor, longer source lifetime, and/or better reliability.

  6. Design and test of superconducting RF cavity prototypes for high intensity proton accelerators

    NASA Astrophysics Data System (ADS)

    Junquera, T.; Biarrotte, J. L.; Saugnac, H.; Gassot, H.; Lesrel, J.; Olry, G.; Bousson, S.; Safa, H.; Charrier, J. P.; Devanz, G.

    2002-05-01

    High intensity proton beams, in the multi-MW range (typically 1 GeV and a few mA) are considered today for different applications: neutron sources, nuclear waste transmutation, radioactive ion beams and neutrino factories. All the foreseen projects are based on superconducting RF cavities for the high energy part of the linac accelerator between 100 MeV and 1 GeV. In this paper we present conceptual and experimental work made by the French group in the R&D preliminary phase. The aim of this study was to design an optimized cavity prototype integrating the more recent progress on RF superconductivity in terms of fabrication and preparation techniques. To reach high accelerating gradients while keeping safety margins and good reliability imposes careful cavity geometry optimization and detailed study of some important technological issues. The most relevant results obtained with several cavity prototypes (accelerating gradient, multipactor,…) are presented. Some other important components of the cavity (helium tank and cold tuner) are also discussed.

  7. Scaling to Ultra-High Intensities by High-Energy Petawatt Beam Combining

    SciTech Connect

    Siders, C W; Jovanovic, I; Crane, J; Rushford, M; Lucianetti, A; Barty, C J

    2006-06-23

    The output pulse energy from a single-aperture high-energy laser amplifier (e.g. fusion lasers such as NIF and LMJ) are critically limited by a number of factors including optical damage, which places an upper bound on the operating fluence; parasitic gain, which limits together with manufacturing costs the maximum aperture size to {approx} 40-cm; and non-linear phase effects which limits the peak intensity. For 20-ns narrow band pulses down to transform-limited sub-picosecond pulses, these limiters combine to yield 10-kJ to 1-kJ maximum pulse energies with up to petawatt peak power. For example, the Advanced Radiographic Capability (ARC) project at NIF is designed to provide kilo-Joule pulses from 0.75-ps to 50-ps, with peak focused intensity above 10{sup 19} W/cm{sup 2}. Using such a high-energy petawatt (HEPW) beamline as a modular unit, they discuss large-scale architectures for coherently combining multiple HEPW pulses from independent apertures, called CAPE (Coherent Addition of Pulses for Energy), to significantly increase the peak achievable focused intensity. Importantly, the maximum intensity achievable with CAPE increases non-linearly. Clearly, the total integrated energy grows linearly with the number of apertures N used. However, as CAPE combines beams in the focal plane by increasing the angular convergence to focus (i.e. the f-number decreases), the foal spot diameter scales inversely with N. Hence the peak intensity scales as N{sup 2}. Using design estimates for the focal spot size and output pulse energy (limited by damage fluence on the final compressor gratings) versus compressed pulse duration in the ARC system, Figure 2 shows the scaled focal spot intensity and total energy for various CAPE configurations from 1,2,4, ..., up to 192 total beams. They see from the fixture that the peak intensity for event modest 8 to 16 beam combinations reaches the 10{sup 21} to 10{sup 22} W/cm{sup 2} regime. With greater number of apertures, or with

  8. Focusing of short-pulse high-intensity laser-accelerated proton beams

    NASA Astrophysics Data System (ADS)

    Bartal, Teresa; Foord, Mark E.; Bellei, Claudio; Key, Michael H.; Flippo, Kirk A.; Gaillard, Sandrine A.; Offermann, Dustin T.; Patel, Pravesh K.; Jarrott, Leonard C.; Higginson, Drew P.; Roth, Markus; Otten, Anke; Kraus, Dominik; Stephens, Richard B.; McLean, Harry S.; Giraldez, Emilio M.; Wei, Mingsheng S.; Gautier, Donald C.; Beg, Farhat N.

    2012-02-01

    Recent progress in generating high-energy (>50MeV) protons from intense laser-matter interactions (1018-1021Wcm-2 refs , , , , , , ) has opened up new areas of research, with applications in radiography, oncology, astrophysics, medical imaging, high-energy-density physics, and ion-proton beam fast ignition. With the discovery of proton focusing with curved surfaces, rapid advances in these areas will be driven by improved focusing technologies. Here we report on the first investigation of the generation and focusing of a proton beam using a cone-shaped target. We clearly show that the focusing is strongly affected by the electric fields in the beam in both open and enclosed (cone) geometries, bending the trajectories near the axis. Also in the cone geometry, a sheath electric field effectively `channels' the proton beam through the cone tip, substantially improving the beam focusing properties. These results agree well with particle simulations and provide the physics basis for many future applications.

  9. Resistively enhanced proton acceleration via high-intensity laser interactions with cold foil targets

    SciTech Connect

    Gibbon, Paul

    2005-08-01

    The acceleration of MeV protons by high-intensity laser interaction with foil targets is studied using a recently developed plasma simulation technique. Based on a hierarchical N-body tree algorithm, this method provides a natural means of treating three-dimensional, collisional transport effects hitherto neglected in conventional explicit particle-in-cell simulations. For targets with finite resistivity, hot electron transport is strongly inhibited, even at temperatures in the MeV range. This leads to suppression of ion acceleration from the rear of the target and an enhancement in energies and numbers of protons originating from the front.

  10. High-intensity laser-driven proton acceleration enhancement from hydrogen containing ultrathin targets

    SciTech Connect

    Dollar, F.; Reed, S. A.; Matsuoka, T.; Bulanov, S. S.; Chvykov, V.; Kalintchenko, G.; McGuffey, C.; Rousseau, P.; Thomas, A. G. R.; Willingale, L.; Yanovsky, V.; Krushelnick, K.; Maksimchuk, A.; Litzenberg, D. W.

    2013-09-30

    Laser driven proton acceleration experiments from micron and submicron thick targets using high intensity (2 × 10{sup 21} W/cm{sup 2}), high contrast (10{sup −15}) laser pulses show an enhancement of maximum energy when hydrogen containing targets were used instead of non-hydrogen containing. In our experiments, using thin (<1μm) plastic foil targets resulted in maximum proton energies that were consistently 20%–100% higher than when equivalent thickness inorganic targets, including Si{sub 3}N{sub 4} and Al, were used. Proton energies up to 20 MeV were measured with a flux of 10{sup 7} protons/MeV/sr.

  11. Proton acceleration with high intensity lasers interacting on micro-cone targets

    NASA Astrophysics Data System (ADS)

    D'Humieres, Emmanuel; Cowan, Tom; Gaillard, Sandrine; Le Galloudec, Nathalie; Rassuchine, Jennifer; Sentoku, Yasuhiko

    2006-10-01

    In the last few years, intense research has been conducted on laser-accelerated ion sources and their applications [1,2]. Proton beams accelerated from solid planar targets have exceptional properties that open new opportunities for ion beam generation and control. Experiments conducted at LANL and LULI have shown that high intensity lasers interacting on micro-cone targets can produce proton beams more collimated and more energetic than with planar targets. These micro-cone targets are composed of a curved cone attached to a micro-table. 2D PIC simulations were performed to understand the experiments and separate the effect of the cone from the effect of the micro-table. These new targets could help increase the laser-accelerated protons maximum energy to the 100 MeV range. [1] J. Fuchs et al., Nature Physics 2, 48 (2006). [2] T.Toncian et al., Science Vol. 312, 21 April 2006, p.410-413.

  12. PRaVDA: High Energy Physics towards proton Computed Tomography

    NASA Astrophysics Data System (ADS)

    Price, T.

    2016-07-01

    Proton radiotherapy is an increasingly popular modality for treating cancers of the head and neck, and in paediatrics. To maximise the potential of proton radiotherapy it is essential to know the distribution, and more importantly the proton stopping powers, of the body tissues between the proton beam and the tumour. A stopping power map could be measured directly, and uncertainties in the treatment vastly reduce, if the patient was imaged with protons instead of conventional x-rays. Here we outline the application of technologies developed for High Energy Physics to provide clinical-quality proton Computed Tomography, in so reducing range uncertainties and enhancing the treatment of cancer.

  13. Start-to-end simulations for the proposed Fermilab high intensity proton source

    SciTech Connect

    Carneiro, Jean-Paul; Johnson, D.E.; Webber, R.C.; /Fermilab

    2007-06-01

    A High Intensity Proton Source consisting in an 8 GeV superconducting H-minus linac and transfer line to the Main Injector has been proposed. The primary mission is to increase the intensity of the Fermilab Main Injector for the production of neutrino superbeams. Start-to-end simulations from the RFQ to the stripping foil using the simulation code TRACK (ANL) is presented in this paper. In particular, we will study the impact of jitter errors on the H-minus phase space at the stripping foil.

  14. The use of ionization electron columns for space-charge compensation in high intensity proton accelerators

    SciTech Connect

    Shiltsev, V.; Alexahin, Y.; Kamerdzhiev, V.; Kapin, V.; Kuznetsov, G.; /Fermilab

    2009-01-01

    We discuss a recent proposal to use strongly magnetized electron columns created by beam ionization of the residual gas for compensation of space charge forces of high intensity proton beams in synchrotrons and linacs. The electron columns formed by trapped ionization electrons in a longitudinal magnetic field that assures transverse distribution of electron space charge in the column is the same as in the proton beam. Electrostatic electrodes are used to control the accumulation and release of the electrons. Ions are not magnetized and drift away without affecting the compensation. Possible technical solution for the electron columns is presented. We also discuss the first numerical simulation results for space-charge compensation in the FNAL Booster and results of relevant beam studies in the Tevatron.

  15. The Use of Ionization Electron Columns for Space-Charge Compensation in High Intensity Proton Accelerators

    SciTech Connect

    Shiltsev, V.; Alexahin, Y.; Kamerdzhiev, V.; Kapin, V.; Kuznetsov, G.

    2009-01-22

    We discuss a recent proposal to use strongly magnetized electron columns created by beam ionization of the residual gas for compensation of space charge forces of high intensity proton beams in synchrotrons and linacs. The electron columns formed by trapped ionization electrons in a longitudinal magnetic field that assures transverse distribution of electron space charge in the column is the same as in the proton beam. Electrostatic electrodes are used to control the accumulation and release of the electrons. Ions are not magnetized and drift away without affecting the compensation. Possible technical solution for the electron columns is presented. We also discuss the first numerical simulation results for space-charge compensation in the FNAL Booster and results of relevant beam studies in the Tevatron.

  16. Reduction of proton acceleration in high-intensity laser interaction with solid two-layer targets

    SciTech Connect

    Wei, M. S.; Davies, J. R.; Clark, E. L.; Beg, F. N.; Gopal, A.; Tatarakis, M.; Willingale, L.; Nilson, P.; Dangor, A. E.; Norreys, P. A.; Zepf, M.; Krushelnick, K.

    2006-12-15

    Reduction of proton acceleration in the interaction of a high-intensity, picosecond laser with a 50-{mu}m aluminum target was observed when 0.1-6 {mu}m of plastic was deposited on the back surface (opposite side of the laser). The maximum energy and number of energetic protons observed at the back of the target were greatly reduced in comparison to pure aluminum and plastic targets of the same thickness. This is attributed to the effect of the interface between the layers. Modeling of the electron propagation in the targets using a hybrid code showed strong magnetic-field generation at the interface and rapid surface heating of the aluminum layer, which may account for the results.

  17. Parasitic slow extraction of extremely weak beam from a high-intensity proton rapid cycling synchrotron

    NASA Astrophysics Data System (ADS)

    Zou, Ye; Tang, Jingyu; Yang, Zheng; Jing, Hantao

    2014-02-01

    This paper proposes a novel method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron (RCS) in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction method from a synchrotron by employing third-order resonance cannot be applied in a high-intensity RCS due to a very short flat-top at the extraction energy and the strict control on beam loss. The proposed parasitic slow extraction method moves the beam to scrape a scattering foil prior to the fast beam extraction by employing either a local orbit bump or momentum deviation or their combination, so that the halo part of the beam will be scattered. A part of the scattered particles will be extracted from the RCS and guided to the experimental area. The slow extraction process can last about a few milliseconds before the beam is extracted by the fast extraction system. The method has been applied to the RCS of China Spallation Neutron Source. With 1.6 GeV in the extraction energy, 62.5 μA in the average current and 25 Hz in the repetition rate for the RCS, the proton intensity by the slow extraction method can be up to 2×104 protons per cycle or 5×105 protons per second. The extracted beam has also a good time structure of approximately uniform in a spill which is required for many applications such as detector tests. Detailed studies including the scattering effect in the foil, the local orbit bump by the bump magnets and dispersive orbit bump by modifying the RF pattern, the multi-particle simulations by ORBIT and TURTLE codes, and some technical features for the extraction magnets are presented.

  18. An improved permanent magnet quadrupole design with larger good field region for high intensity proton linacs

    NASA Astrophysics Data System (ADS)

    Mathew, Jose V.; Rao, S. V. L. S.; Krishnagopal, S.; Singh, P.

    2013-11-01

    The Low Energy High Intensity Proton Accelerator (LEHIPA), being developed at the Bhabha Atomic Research Centre (BARC) will produce a 20 MeV, 30 mA, continuous wave (CW) proton beam. At these low velocities, space-charge forces dominate, and could lead to larger beam sizes and beam halos. Hence in the design of the focusing lattice of the LEHIPA drift tube linac (DTL) using permanent magnet quadrupoles (PMQs), a larger good field region is preferred. Here we study, using the two dimensional (2D) and three dimensional (3D) simulation codes PANDIRA and RADIA, four different types of cylindrical PMQ designs: 16-segment trapezoidal Halbach configuration, bullet-nosed geometry and 8- and 16-segment rectangular geometries. The trapezoidal Halbach geometry is used in a variety of accelerators since it provides very high field gradients in small bores, while the bullet-nosed geometry, which is a combination of the trapezoidal and rectangular designs, is used in some DTLs. This study shows that a larger good field region is possible in the 16-segment rectangular design as compared to the Halbach and bullet-nosed designs, making it more attractive for high-intensity proton linacs. An improvement in good-field region by ˜16% over the Halbach design is obtained in the optimized 16-segment rectangular design, although the field gradient is lower by ˜20%. Tolerance studies show that the rectangular segment PMQ design is substantially less sensitive to the easy axis orientation errors and hence will be a better choice for DTLs.

  19. Intial characterization fo a commerical electron gun for profiling high intensity proton beams in Project X

    SciTech Connect

    Thurman-Keup, R.; Johnson, A.S.; Lumpkin, A.H.; Thangaraj, J.C.T.; Zhang, D.; Blokland, W.; /Oak Ridge

    2011-03-01

    Measuring the profile of a high-intensity proton beam is problematic in that traditional invasive techniques such as flying wires don't survive the encounter with the beam. One alternative is the use of an electron beam as a probe of the charge distribution in the proton beam as was done at the Spallation Neutron Source at ORNL. Here we present an initial characterization of the beam from a commercial electron gun from Kimball Physics, intended for use in the Fermilab Main Injector for Project X. Despite the fact that the horizontal spot size is abnormally large in the high current measurement, the spot size at the downstream cross X2 is reasonable in the context of measuring the deflection. A thin foil OTR would help with the beam heating and should be tried. The next phase of this experiment is to simulate the proton beam with a pair of current carrying wires and to design and construct a fast deflector. Some of the remaining issues to be considered include determining the minimum beam current needed to observe the deflected beam for a given sweep time and the impact of longitudinal variations in the charge density of the bunch.

  20. Calculation of acceptance of high intensity superconducting proton linac for Project X

    SciTech Connect

    Saini, A.; Ranjan, K.; Solyak, N.; Mishra, S.; Yakovlev, V.; /Fermilab

    2011-03-01

    Project-X is the proposed high intensity proton facility to be built at Fermilab, US. Its Superconducting Linac, to be used at first stage of acceleration, will be operated in continuous wave (CW) mode. The Linac is divided into three sections on the basis of operating frequencies & six sections on the basis of family of RF cavities to be used for the acceleration of beam from 2.5 MeV to 3 GeV. The transition from one section to another can limit the acceptance of the Linac if these are not matched properly. We performed a study to calculate the acceptance of the Linac in both longitudinal and transverse plane. Investigation of most sensitive area which limits longitudinal acceptance and study of influence of failure of beam line elements at critical position, on acceptance are also performed.

  1. Final Report for "Modeling Electron Cloud Diagnostics for High-Intensity Proton Accelerators"

    SciTech Connect

    Seth A Veitzer

    2009-09-25

    Electron clouds in accelerators such as the ILC degrade beam quality and limit operating efficiency. The need to mitigate electron clouds has a direct impact on the design and operation of these accelerators, translating into increased cost and reduced performance. Diagnostic techniques for measuring electron clouds in accelerating cavities are needed to provide an assessment of electron cloud evolution and mitigation. Accurate numerical modeling of these diagnostics is needed to validate the experimental techniques. In this Phase I, we developed detailed numerical models of microwave propagation through electron clouds in accelerating cavities with geometries relevant to existing and future high-intensity proton accelerators such as Project X and the ILC. Our numerical techniques and simulation results from the Phase I showed that there was a high probability of success in measuring both the evolution of electron clouds and the effects of non-uniform electron density distributions in Phase II.

  2. 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.

  3. Beam dynamic design of a high intensity injector for proton linac

    NASA Astrophysics Data System (ADS)

    Dou, Wei-Ping; Wang, Zhi-Jun; Jia, Fang-Jian; He, Yuan; Wang, Zhi; Lu, Yuan-Rong

    2016-08-01

    A compact room-temperature injector is designed to accelerate 100 mA proton beam from 45 keV to 4.06 MeV for the proposed high intensity proton linac at State Key Lab of Nuclear Physics and Technology in Peking university. The main feature is that the Radio Frequency Quadruple (RFQ) and the Drift Tube linac (DTL) sections are merged in one piece at the total length of 276 cm. The beam is matched in transverse directions with an compact internal doublet instead of an external matching section in between. The design has reached a high average accelerating gradient up to 1.55 MV/m with transmission efficiency of 95.9% at the consideration of high duty factor operation. The operation frequency is chose to be 200 MHz due to the already available RF power source. The injector combines a 150 cm long 4-vanes RFQ internal section from 45 keV to 618 keV with a 126 cm long H-type DTL section to 4.06 MeV. In general the design satisfy the challenges of the project requirements. And the details are presented in this paper.

  4. Monoenergetic proton emission from nuclear reaction induced by high intensity laser-generated plasma

    SciTech Connect

    Torrisi, L.; Cavallaro, S.; Giuffrida, L.; Cutroneo, M.; Krasa, J.; Margarone, D.; Velyhan, A.; Ullschmied, J.; Kravarik, J.; Wolowski, J.; Szydlowski, A.; Rosinski, M.

    2012-02-15

    A 10{sup 16} W/cm{sup 2} Asterix laser pulse intensity, 1315 nm at the fundamental frequency, 300 ps pulse duration, was employed at PALS laboratory of Prague, to irradiate thick and thin primary CD{sub 2} targets placed inside a high vacuum chamber. The laser irradiation produces non-equilibrium plasma with deutons and carbon ions emission with energy of up to about 4 MeV per charge state, as measured by time-of-flight (TOF) techniques by using ion collectors and silicon carbide detectors. Accelerated deutons may induce high D-D cross section for fusion processes generating 3 MeV protons and 2.5 MeV neutrons, as measured by TOF analyses. In order to increase the mono-energetic proton yield, secondary CD{sub 2} targets can be employed to be irradiated by the plasma-accelerated deutons. Experiments demonstrated that high intensity laser pulses can be employed to promote nuclear reactions from which characteristic ion streams may be developed. Results open new scenario for applications of laser-generated plasma to the fields of ion sources and ion accelerators.

  5. Fission foil detector calibrations with high energy protons

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Frank, A. L.

    1995-01-01

    Fission foil detectors (FFD's) are passive devices composed of heavy metal foils in contact with muscovite mica films. The heavy metal nuclei have significant cross sections for fission when irradiated with neutrons and protons. Each isotope is characterized by threshold energies for the fission reactions and particular energy-dependent cross sections. In the FFD's, fission fragments produced by the reactions are emitted from the foils and create latent particle tracks in the adjacent mica films. When the films are processed surface tracks are formed which can be optically counted. The track densities are indications of the fluences and spectra of neutrons and/or protons. In the past, detection efficiencies have been calculated using the low energy neutron calibrated dosimeters and published fission cross sections for neutrons and protons. The problem is that the addition of a large kinetic energy to the (n,nucleus) or (p,nucleus) reaction could increase the energies and ranges of emitted fission fragments and increase the detector sensitivity as compared with lower energy neutron calibrations. High energy calibrations are the only method of resolving the uncertainties in detector efficiencies. At high energies, either proton or neutron calibrations are sufficient since the cross section data show that the proton and neutron fission cross sections are approximately equal. High energy proton beams have been utilized (1.8 and 4.9 GeV, 80 and 140 MeV) for measuring the tracks of fission fragments emitted backward and forward.

  6. Using high-intensity laser-generated energetic protons to radiograph directly driven implosions.

    PubMed

    Zylstra, A B; Li, C K; Rinderknecht, H G; Séguin, F H; Petrasso, R D; Stoeckl, C; Meyerhofer, D D; Nilson, P; Sangster, T C; Le Pape, S; Mackinnon, A; Patel, P

    2012-01-01

    The recent development of petawatt-class lasers with kilojoule-picosecond pulses, such as OMEGA EP [L. Waxer et al., Opt. Photonics News 16, 30 (2005)], provides a new diagnostic capability to study inertial-confinement-fusion (ICF) and high-energy-density (HED) plasmas. Specifically, petawatt OMEGA EP pulses have been used to backlight OMEGA implosions with energetic proton beams generated through the target normal sheath acceleration (TNSA) mechanism. This allows time-resolved studies of the mass distribution and electromagnetic field structures in ICF and HED plasmas. This principle has been previously demonstrated using Vulcan to backlight six-beam implosions [A. J. Mackinnon et al., Phys. Rev. Lett. 97, 045001 (2006)]. The TNSA proton backlighter offers better spatial and temporal resolution but poorer spatial uniformity and energy resolution than previous D(3)He fusion-based techniques [C. Li et al., Rev. Sci. Instrum. 77, 10E725 (2006)]. A target and the experimental design technique to mitigate potential problems in using TNSA backlighting to study full-energy implosions is discussed. The first proton radiographs of 60-beam spherical OMEGA implosions using the techniques discussed in this paper are presented. Sample radiographs and suggestions for troubleshooting failed radiography shots using TNSA backlighting are given, and future applications of this technique at OMEGA and the NIF are discussed. PMID:22299955

  7. High energy protons generation by two sequential laser pulses

    SciTech Connect

    Wang, Xiaofeng; Shen, Baifei E-mail: zhxm@siom.ac.cn; Zhang, Xiaomei E-mail: zhxm@siom.ac.cn; Wang, Wenpeng; Xu, Jiancai; Yi, Longqing; Shi, Yin

    2015-04-15

    The sequential proton acceleration by two laser pulses of relativistic intensity is proposed to produce high energy protons. In the scheme, a relativistic super-Gaussian (SG) laser pulse followed by a Laguerre-Gaussian (LG) pulse irradiates dense plasma attached by underdense plasma. A proton beam is produced from the target and accelerated in the radiation pressure regime by the short SG pulse and then trapped and re-accelerated in a special bubble driven by the LG pulse in the underdense plasma. The advantages of radiation pressure acceleration and LG transverse structure are combined to achieve the effective trapping and acceleration of protons. In a two-dimensional particle-in-cell simulation, protons of 6.7 GeV are obtained from a 2 × 10{sup 22 }W/cm{sup 2} SG laser pulse and a LG pulse at a lower peak intensity.

  8. Beam Dynamics Studies and the Design, Fabrication and Testing of Superconducting Radiofrequency Cavity for High Intensity Proton Accelerator

    SciTech Connect

    Saini, Arun

    2012-03-01

    The application horizon of particle accelerators has been widening significantly in recent decades. Where large accelerators have traditionally been the tools of the trade for high-energy nuclear and particle physics, applications in the last decade have grown to include large-scale accelerators like synchrotron light sources and spallation neutron sources. Applications like generation of rare isotopes, transmutation of nuclear reactor waste, sub-critical nuclear power, generation of neutrino beams etc. are next area of investigation for accelerator scientific community all over the world. Such applications require high beam power in the range of few mega-watts (MW). One such high intensity proton beam facility is proposed at Fermilab, Batavia, US, named as Project-X. Project-X facility is based on H- linear accelerator (linac), which will operate in continuous wave (CW) mode and accelerate H- ion beam with average current of 1 mA from kinetic energy of 2.5 MeV to 3 GeV to deliver 3MW beam power. One of the most challenging tasks of the Project-X facility is to have a robust design of the CW linac which can provide high quality beam to several experiments simultaneously. Hence a careful design of linac is important to achieve this objective.

  9. Proton-proton and proton-antiproton elastic scattering at high energies: Theory, phenomenology, and experiment

    SciTech Connect

    Wu, Tai Tsun.

    1990-01-01

    This is a brief review of the progress in the understanding, during the past twenty years, of hadronic elastic scattering near the forward direction at high energies. On the basis of quantum gauge field theories, the Pomeron is found to be a branch cut above 1. Using the physical picture that this result implies, phenomenology for proton-proton and antiproton-proton elastic scattering is constructed. Two noteworthy features are that, at high energies, both the total cross section and the ratio of the integrated elastic cross section to the total cross section to the total cross section are increasing functions of the center-of-mass energy. Detailed predictions are given for the elastic differential cross sections, Coulomb interference and the ratios of the real to imaginary parts of the forward amplitudes. These predictions have been extensively and accurately confirmed by experiments, and have also been given both for future experiments on existing accelerators and for experiments on future accelerators. 14 refs., 2 figs.

  10. Proton-proton and proton-antiproton elastic scattering at high energies: Theory, phenomenology, and experiment

    SciTech Connect

    Wu, Tai Tsun

    1990-12-31

    This is a brief review of the progress in the understanding, during the past twenty years, of hadronic elastic scattering near the forward direction at high energies. On the basis of quantum gauge field theories, the Pomeron is found to be a branch cut above 1. Using the physical picture that this result implies, phenomenology for proton-proton and antiproton-proton elastic scattering is constructed. Two noteworthy features are that, at high energies, both the total cross section and the ratio of the integrated elastic cross section to the total cross section to the total cross section are increasing functions of the center-of-mass energy. Detailed predictions are given for the elastic differential cross sections, Coulomb interference and the ratios of the real to imaginary parts of the forward amplitudes. These predictions have been extensively and accurately confirmed by experiments, and have also been given both for future experiments on existing accelerators and for experiments on future accelerators. 14 refs., 2 figs.

  11. Shielding Benchmark Experiments Through Concrete and Iron with High-Energy Proton and Heavy Ion Accelerators

    NASA Astrophysics Data System (ADS)

    Nakamura, T.; Sasaki, M.; Nunomiya, T.; Nakao, N.; Kim, E.; Kurosawa, T.; Taniguchi, S.; Iwase, H.; Uwamino, Y.; Shibata, T.; Ito, S.; Fukumura, A.; Perry, D. R.; Wright, P.

    The deep penetration of neutrons through thick shield has become a very serious problem in the shielding design of high-energy, high-intensity accelerator facility. In the design calculation, the Monte Carlo transport calculation through thick shields has large statistical errors and the basic nuclear data and model used in the existing Monte Carlo codes are not well evaluated because of very few experimental data. It is therefore strongly needed to do the deep penetration experiment as shielding benchmark for investigating the calculation accuracy. Under this circumference, we performed the following two shielding experiments through concrete and iron, one with a 800 MeV proton accelerator of the Rutherford Appleton Laboratory (RAL), England and the other with a high energy heavy iron accelerator of the National Institute of Radiological Sciences (NIRS), Japan. Here these two shielding benchmark experiments are outlined.

  12. Investigation of high-energy-proton effects in aluminum

    SciTech Connect

    Czajkowski, C.J.; Snead, C.L. Jr.; Todosow, M.

    1997-12-01

    Specimens of 1100 aluminum were exposed to several fluences of 23.5-GeV protons at the Brookhaven Alternating Gradient Synchrotron. Although this energy is above those currently being proposed for spallation-neutron applications, the results can be viewed as indicative of trends and other microstructural evolution with fluence that take place with high-energy proton exposures such as those associated with an increasing ratio of gas generation to dpa. TEM investigation showed significantly larger bubble size and lower density of bubbles compared with lower-energy proton results. Additional testing showed that the tensile strength increased with fluence as expected, but the microhardness decreased, a result for which an intepretation is still under investigation.

  13. About multiple scattering of high energy protons in crystal deflectors

    NASA Astrophysics Data System (ADS)

    Taratin, A. M.; Scandale, W.

    2015-07-01

    The process of multiple scattering of high energy protons in a silicon crystal at its amorphous orientation was studied by simulation of proton trajectories in the model of binary collisions and by a straight simulation of the sequences of proton collisions with atoms when their impact parameters are randomly and uniformly distributed on the symmetry cell for a given crystallography direction. The value of the RMS deflection of multiple scattering obtained by the simulation is in a good agreement with the experiment and more than 15% larger than it follows from the Moliere theory. The obtained RMS deflection used in the Gaussian approach of multiple scattering well describes dechanneling of protons in the frame of the planar potential model. Different number of proton collisions with atoms occurs along the same crystal length for different crystal orientations. However, the change of the collision number is compensated by the corresponding change of the mean square deflection in a single collision. Therefore, multiple scattering is the same for different crystal orientations. The generator of multiple scattering for amorphous crystal orientations was proposed.

  14. Si film separation obtained by high energy proton implantation

    SciTech Connect

    Braley, C.; Mazen, F.; Papon, A.-M.; Rieutord, F.; Charvet, A.-M.; Ntsoenzok, E.

    2012-11-06

    High energy protons implantation in the 1-1.5 MeV range can be used to detach free-standing thin silicon films with thickness between 15 and 30 {mu}m. Recently, we showed that Si orientation has a strong effect on the layer separation threshold fluence and efficiency. While complete delamination of (111)Si films is achieved, (100)Si films separation is more challenging due to blistering phenomena or partial separation of the implanted layer. In this work, we study the fracture mechanism in (100) and (111)Si after high energy implantation in order to understand the origin of such a behavior. We notably point out that fracture precursor defects, i.e. the platelets, preferentially form on (111) planes, as a consequence of the low strain level in the damaged region in our implantation conditions. Fracture therefore propagates easily in (111)Si, while it requires higher fluence to overcome unfavorable precursors orientation and propagate in (100)Si.

  15. Hole-boring radiation pressure proton acceleration at high intensity in near-critical density targets

    NASA Astrophysics Data System (ADS)

    Yu, Jinqing; Dover, N. P.; Jin, Xiaolin; Li, Bin; Dangor, A. E.; Najmudin, Z.

    2014-10-01

    We will present high quality proton beams accelerated from hole-boring radiation pressure proton acceleration (HB-RPA) using three-dimension Particle-in-Cell simulation results. Scaling works on proton cut off energy with laser parameters such as laser intensity and laser pulse duration have been studied in detail by two-dimension Particle-in-Cell simulations. Optimal conditions for generating proton beam of narrow energy spread will be discussed.

  16. High-Intensity Scattering Processes of Relativistic Electrons in Vacuum and Their Relevance to High-Energy Astrophysics

    SciTech Connect

    Hartemann, Frederic V.; Troha, Anthony L.; Baldis, Hector A.; Gupta, Atul; Kerman, Arthur K.; Landahl, Eric C.; Luhmann, Neville C. Jr.; Van Meter, James R.

    2000-04-01

    The recent advent of ultra-short pulse, high-intensity lasers, together with advances in other novel technologies, such as high-gradient radiofrequency photoinjectors, have afforded researchers the possibility to simulate astrophysical conditions in the laboratory. Laser-produced plasmas have been successfully used to simulate astrophysical plasmas and supernovae in the laboratory for several years. Now, femtosecond laser systems operating in the terawatt to petawatt range are available, as are synchronized relativistic electron bunches with subpicosecond durations and terahertz bandwidths. With these tools, experiments have been conducted to study phenomena related to supernova explosions, stellar winds, solar coronae, cosmic rays, planetary and celestial matter, and interstellar plasmas. Other experiments have been proposed to investigate Unruh radiation, as well as ponderomotive scattering, which can accelerate electrons in vacuum to relativistic energies using the extremely high gradients in a three-dimensional laser focus. The nonlinear Doppler shift induced by ultrarelativistic radiation pressure is shown to yield complex nonlinear Compton backscattered spectra. Finally, strong radiative corrections are expected when the Doppler-upshifted laser wavelength approaches the Compton scale. These are discussed within the context of high-field classical electrodynamics, a new discipline borne out of the aforementioned innovations. (c) 2000 The American Astronomical Society.

  17. Microstructured snow targets for high energy quasi-monoenergetic proton acceleration

    NASA Astrophysics Data System (ADS)

    Schleifer, E.; Nahum, E.; Eisenmann, S.; Botton, M.; Baspaly, A.; Pomerantz, I.; Abricht, F.; Branzel, J.; Priebe, G.; Steinke, S.; Andreev, A.; Schnuerer, M.; Sandner, W.; Gordon, D.; Sprangle, P.; Ledingham, K. W. D.; Zigler, A.

    2013-05-01

    Compact size sources of high energy protons (50-200MeV) are expected to be key technology in a wide range of scientific applications 1-8. One promising approach is the Target Normal Sheath Acceleration (TNSA) scheme 9,10, holding record level of 67MeV protons generated by a peta-Watt laser 11. In general, laser intensity exceeding 1018 W/cm2 is required to produce MeV level protons. Another approach is the Break-Out Afterburner (BOA) scheme which is a more efficient acceleration scheme but requires an extremely clean pulse with contrast ratio of above 10-10. Increasing the energy of the accelerated protons using modest energy laser sources is a very attractive task nowadays. Recently, nano-scale targets were used to accelerate ions 12,13 but no significant enhancement of the accelerated proton energy was measured. Here we report on the generation of up to 20MeV by a modest (5TW) laser system interacting with a microstructured snow target deposited on a Sapphire substrate. This scheme relax also the requirement of high contrast ratio between the pulse and the pre-pulse, where the latter produces the highly structured plasma essential for the interaction process. The plasma near the tip of the snow target is subject to locally enhanced laser intensity with high spatial gradients, and enhanced charge separation is obtained. Electrostatic fields of extremely high intensities are produced, and protons are accelerated to MeV-level energies. PIC simulations of this targets reproduce the experimentally measured energy scaling and predict the generation of 150 MeV protons from laser power of 100TW laser system18.

  18. Generation and focusing of short pulse high intensity laser accelerated protons

    NASA Astrophysics Data System (ADS)

    Foord, Mark E.

    2011-10-01

    Much progress has recently been reported in generating MeV energy protons from intense laser-matter interactions, having potential applications in areas such as radiography, oncology, and ion-proton beam fast ignition. Experiments were conducted on the sub-ps LANL Trident laser, where we systematically investigated proton focusing and conversion efficiency from curved surface targets in both open and closed cone-shaped target geometries. We clearly show that the focusing is strongly affected by the electric fields in the beam, bending the trajectories near the axis. We also find that in the cone geometry, a sheath electric field effectively ``channels'' the proton beam through the cone tip, substantially improving the beam focusing properties. The far-field energy and angular distribution of the proton beam were measured using a mesh that images the beam onto a RCF detector. For the cone-shaped targets using a 300 μm-radius curved surface foil, a 60 μm diameter proton spot was determined. Proton generation and focusing were modeled using 2-D hybrid PIC simulations, which compared well with RCF data. The proton conversion efficiency varied strongly with the target geometry. Simulations indicate this is due to that charge flow on the structure and the coupling to the hot electrons and electric fields in the plasma. Work performed under US DOE contract DE-AC52-07NA27344

  19. Proton Linac Front End for High Intensity Neutrino Source at Fermilab

    NASA Astrophysics Data System (ADS)

    Tam, Wai-Ming; Apollinari, Giorgio; Madrak, Robyn; Moretti, Alfred; Ristori, Leonardo; Romanov, Gennady; Steimel, James; Webber, Robert; Wildman, David

    2008-04-01

    Fermilab has recently proposed the construction of an 8 GeV superconducting linac for the exploration of the high intensity frontier. The High Intensity Neutrino Source (HINS) R&D program was established to explore the feasibility of certain technical solutions proposed for the front end of a high intensity linac. The low energy (˜60 MeV) section operates at 325 MHz and comprises an RFQ, two re-buncher cavities, 16 room temperature (RT) and 29 superconducting cross-bar H-type resonators, and superconducting solenoid focusing elements. One of the distinguishing features of this linac is the use of one klystron to feed multiple radio frequency (RF) elements. As an example, the RFQ, the re-bunchers and the 16 RT cavities are powered by a single 2.5 MW pulsed klystron. To achieve individual control over the phase and the voltage amplitude, each of the RF elements is equipped with a high power vector modulator. The RF control system will be discussed. The first RT cavity is completed with a power coupler, two mechanical tuners, vacuum and cooling systems, and has been RF conditioned. Preliminary tests on resonance frequency stability control and tests results of the cavity resonance frequency response to cooling water temperature and tuner position will also be discussed.

  20. Focusing and transport of high-intensity multi-MeV proton bunches from a compact laser-driven source

    NASA Astrophysics Data System (ADS)

    Busold, S.; Schumacher, D.; Deppert, O.; Brabetz, C.; Frydrych, S.; Kroll, F.; Joost, M.; Al-Omari, H.; Blažević, A.; Zielbauer, B.; Hofmann, I.; Bagnoud, V.; Cowan, T. E.; Roth, M.

    2013-10-01

    Laser ion acceleration provides for compact, high-intensity ion sources in the multi-MeV range. Using a pulsed high-field solenoid, for the first time high-intensity laser-accelerated proton bunches could be selected from the continuous exponential spectrum and delivered to large distances, containing more than 109 particles in a narrow energy interval around a central energy of 9.4 MeV and showing ≤30mrad envelope divergence. The bunches of only a few nanoseconds bunch duration were characterized 2.2 m behind the laser-plasma source with respect to arrival time, energy width, and intensity as well as spatial and temporal bunch profile.

  1. High-intensity pulsed source of polarized protons with an atomic beam

    SciTech Connect

    Belov, A.S.; Esin, S.K.; Kubalov, S.A.; Kuzik, V.E.; Stepanov, A.A.; Yakushev, V.P.

    1985-10-25

    A source of polarized protons with a beam current up to 2.5 mA in the pulse, a degree of polarization 0.78 +- 0.01, a current pulse length of 120 ..mu..s, and a repetition frequency of 1 Hz is described. This is the first source of polarized protons which makes use of the charge exchange of polarized hydrogen atoms with ions of a deuterium plasma.

  2. Laser-Produced and Accelerated High Energy Protons

    NASA Astrophysics Data System (ADS)

    Cowan, Thomas

    2005-04-01

    Ultra-low emittance, multi-MeV proton beams have recently been produced by the interaction of high-intensity short-pulse lasers with thin metallic foils [1]. The acceleration process proceeds in two steps. First the laser ponderomotively accelerates huge, MA currents of ˜MeV electrons which propagate through the foil and form a dense relativistic electron sheath on the non-irradiated rear surface. This sheath produces an electrostatic field >10^12 V/m that ionizes the surface atoms almost instantaneously, forming a ˜1 nm thick ion layer which, together with the electron sheath, resembles a virtual cathode. The ions are accelerated initially normal to the foil surface, followed by a diverging plasma expansion phase driven by the electron plasma pressure. By structuring the rear surface of the foil, we have succeeded to produce modulations in the transverse phase space of the ions, which resemble fiducial ``beamlets'' within the envelope of the expanding plasma. This allows one to image the initial accelerating sheath, and map the plasma expansion of the beam envelope, to fully reconstruct the transverse phase space. We find that for protons of 10 MeV, the normalized transverse rms emittance is less than 0.004 π mm.mrad [1], i.e. 100-fold better than typical RF accelerators and at substantially higher ion currents exceeding 10 kA. Recent results will be reported on stripping the electrons while maintaining the low emittance from experiments at the LULI 100 TW laser, and theoretical estimates of the lowest emittance which can be expected based on ion heating mechanisms during the initial sheath formation and ion acceleration processes, will be presented. [1] T.E. Cowan, J. Fuchs, H. Ruhl et al., Phys. Rev. Lett. 92, 204801 (2004).

  3. Proton acceleration with high-intensity ultrahigh-contrast laser pulses.

    PubMed

    Ceccotti, T; Lévy, A; Popescu, H; Réau, F; D'Oliveira, P; Monot, P; Geindre, J P; Lefebvre, E; Martin, Ph

    2007-11-01

    We report on simultaneous measurements of backward- and forward-accelerated protons spectra when an ultrahigh intensity (approximately 5 x 10(18) W/cm(20), ultrahigh contrast (>10(10)) laser pulse interacts with foils of thickness ranging from 0.08 to 105 microm. Under such conditions, free of preplasma originating from ionization of the laser-irradiated surface, we show that the maximum proton energies are proportional to the p component of the laser electric field only and not to the ponderomotive force and that the characteristics of the proton beams originating from both target sides are almost identical. All these points have been corroborated by extensive 1D and 2D particle-in-cell simulations showing a very good agreement with the experimental data. PMID:17995415

  4. Proton Acceleration with High-Intensity Ultrahigh-Contrast Laser Pulses

    SciTech Connect

    Ceccotti, T.; Levy, A.; Popescu, H.; Reau, F.; D'Oliveira, P.; Monot, P.; Martin, Ph.; Lefebvre, E.

    2007-11-02

    We report on simultaneous measurements of backward- and forward-accelerated protons spectra when an ultrahigh intensity ({approx}5x10{sup 18} W/cm{sup 2}), ultrahigh contrast (>10{sup 10}) laser pulse interacts with foils of thickness ranging from 0.08 to 105 {mu}m. Under such conditions, free of preplasma originating from ionization of the laser-irradiated surface, we show that the maximum proton energies are proportional to the p component of the laser electric field only and not to the ponderomotive force and that the characteristics of the proton beams originating from both target sides are almost identical. All these points have been corroborated by extensive 1D and 2D particle-in-cell simulations showing a very good agreement with the experimental data.

  5. Hardness assurance for proton direct ionization-induced SEEs using a high-energy proton beam

    SciTech Connect

    Dodds, Nathaniel Anson; Schwank, James R.; Shaneyfelt, Marty R.; Dodd, Paul E.; Doyle, Barney Lee; Trinczek, M.; Blackmore, E. W.; Rodbell, K. P.; Reed, R. A.; Pellish, J. A.; LaBel, K. A.; Marshall, P. W.; Swanson, Scot E.; Vizkelethy, Gyorgy; Van Deusen, Stuart B.; Sexton, Frederick W.; Martinez, Marino J.; Gordon, M. S.

    2014-11-06

    The low-energy proton energy spectra of all shielded space environments have the same shape. This shape is easily reproduced in the laboratory by degrading a high-energy proton beam, producing a high-fidelity test environment. We use this test environment to dramatically simplify rate prediction for proton direct ionization effects, allowing the work to be done at high-energy proton facilities, on encapsulated parts, without knowledge of the IC design, and with little or no computer simulations required. Proton direct ionization (PDI) is predicted to significantly contribute to the total error rate under the conditions investigated. Scaling effects are discussed using data from 65-nm, 45-nm, and 32-nm SOI SRAMs. These data also show that grazing-angle protons will dominate the PDI-induced error rate due to their higher effective LET, so PDI hardness assurance methods must account for angular effects to be conservative. As a result, we show that this angular dependence can be exploited to quickly assess whether an IC is susceptible to PDI.

  6. Hardness assurance for proton direct ionization-induced SEEs using a high-energy proton beam

    DOE PAGESBeta

    Dodds, Nathaniel Anson; Schwank, James R.; Shaneyfelt, Marty R.; Dodd, Paul E.; Doyle, Barney Lee; Trinczek, M.; Blackmore, E. W.; Rodbell, K. P.; Reed, R. A.; Pellish, J. A.; et al

    2014-11-06

    The low-energy proton energy spectra of all shielded space environments have the same shape. This shape is easily reproduced in the laboratory by degrading a high-energy proton beam, producing a high-fidelity test environment. We use this test environment to dramatically simplify rate prediction for proton direct ionization effects, allowing the work to be done at high-energy proton facilities, on encapsulated parts, without knowledge of the IC design, and with little or no computer simulations required. Proton direct ionization (PDI) is predicted to significantly contribute to the total error rate under the conditions investigated. Scaling effects are discussed using data frommore » 65-nm, 45-nm, and 32-nm SOI SRAMs. These data also show that grazing-angle protons will dominate the PDI-induced error rate due to their higher effective LET, so PDI hardness assurance methods must account for angular effects to be conservative. As a result, we show that this angular dependence can be exploited to quickly assess whether an IC is susceptible to PDI.« less

  7. Proton beam generation by ultra-high intensity laser-solid interaction

    NASA Astrophysics Data System (ADS)

    Manclossi, M.; Guemnie-Tafo, A.; Batani, D.; Malka, V.; Fritzler, S.; Lefebvre, E.; D'Humieres, E.

    2005-10-01

    We report on some recent experimental results on proton production from ultra-intense laser pulse interaction with thin aluminium and plastic foil targets. These results were obtained at Laboratoire d'Optique Appliquee with the 100TW 'salle jaune' laser system, delivering 35 fs laser pulses at 0.8 mu m, reaching a maximum intensity on target of a few 10(19) W/cm(2). In such extreme interaction conditions, an intense and collimated relativistic electron current is injected from the plasma created on the laser focal spot into the cold interior of the target. Its transport through dense matter, ruled by both collisions and self-induced (electro-magnetic) field effects, is the driving mechanism for proton acceleration from the rear side of thin foils: when reaching and leaving the foil rear-side, the fast electrons create a large charge separation and a huge electrostatic field with a maximum value of few TV/m, capable of accelerating protons. A parametric study as a function of the laser driver and target parameters indicates an optimal value for target thickness, which strongly depends on the laser prepulse duration. In our experiments, we did irradiate targets of various materials (CH, Al, Au) changing the prepulse duration by using fast Pockels cells in the laser chain. CR-39 nuclear track detectors with Al filters of different thickness and a Thomson parabola were used to detect proton generation. The best results were obtained for 2 mu m Al targets, leading to the generation of proton energies with energies up to 12 MeV.

  8. High intensity proton injector for facility of antiproton and ion research.

    PubMed

    Berezov, R; Brodhage, R; Chauvin, N; Delferriere, O; Fils, J; Hollinger, R; Ivanova, V; Tuske, O; Ullmann, C

    2016-02-01

    The high current ion source with the low energy beam transport (LEBT) will serve as injector into the proton LINAC to provide primary proton beam for the production of antiprotons. The pulsed ion source developed and built in CEA/Saclay operates with a frequency of 2.45 GHz based on ECR plasma production with two coils with 87.5 mT magnetic field necessary for the electron cyclotron resonance. The compact LEBT consists of two solenoids with a maximum magnetic field of 500 mT including two integrated magnetic steerers to adjust the horizontal and vertical beam positions. The total length of the compact LEBT is 2.3 m and was made as short as possible to reduced emittance growth along the beam line. To measure ion beam intensity behind the pentode extraction system, between solenoids and at the end of the beam line, two current transformers and a Faraday cup are installed. To get information about the beam quality and position, the diagnostic chamber with different equipment will be installed between the two solenoids. This article reports the current status of the proton injector for the facility of antiproton and ion research. PMID:26931923

  9. High intensity proton injector for facility of antiproton and ion research

    NASA Astrophysics Data System (ADS)

    Berezov, R.; Brodhage, R.; Chauvin, N.; Delferriere, O.; Fils, J.; Hollinger, R.; Ivanova, V.; Tuske, O.; Ullmann, C.

    2016-02-01

    The high current ion source with the low energy beam transport (LEBT) will serve as injector into the proton LINAC to provide primary proton beam for the production of antiprotons. The pulsed ion source developed and built in CEA/Saclay operates with a frequency of 2.45 GHz based on ECR plasma production with two coils with 87.5 mT magnetic field necessary for the electron cyclotron resonance. The compact LEBT consists of two solenoids with a maximum magnetic field of 500 mT including two integrated magnetic steerers to adjust the horizontal and vertical beam positions. The total length of the compact LEBT is 2.3 m and was made as short as possible to reduced emittance growth along the beam line. To measure ion beam intensity behind the pentode extraction system, between solenoids and at the end of the beam line, two current transformers and a Faraday cup are installed. To get information about the beam quality and position, the diagnostic chamber with different equipment will be installed between the two solenoids. This article reports the current status of the proton injector for the facility of antiproton and ion research.

  10. Proton-Proton On Shell Optical Potential at High Energies and the Hollowness Effect

    NASA Astrophysics Data System (ADS)

    Arriola, Enrique Ruiz; Broniowski, Wojciech

    2016-04-01

    We analyze the usefulness of the optical potential as suggested by the double spectral Mandelstam representation at very high energies, such as in the proton-proton scattering at ISR and the LHC. Its particular meaning regarding the interpretation of the scattering data up to the maximum available measured energies is discussed. Our analysis reconstructs 3D dynamics from the effective transverse 2D impact parameter representation and suggests that besides the onset of gray nucleons at the LHC there appears an inelasticity depletion (hollowness) which precludes convolution models at the attometer scale.

  11. Proton-Proton On Shell Optical Potential at High Energies and the Hollowness Effect

    NASA Astrophysics Data System (ADS)

    Arriola, Enrique Ruiz; Broniowski, Wojciech

    2016-07-01

    We analyze the usefulness of the optical potential as suggested by the double spectral Mandelstam representation at very high energies, such as in the proton-proton scattering at ISR and the LHC. Its particular meaning regarding the interpretation of the scattering data up to the maximum available measured energies is discussed. Our analysis reconstructs 3D dynamics from the effective transverse 2D impact parameter representation and suggests that besides the onset of gray nucleons at the LHC there appears an inelasticity depletion (hollowness) which precludes convolution models at the attometer scale.

  12. CGC/saturation approach for high energy soft interactions: v2 in proton-proton collisions

    NASA Astrophysics Data System (ADS)

    Gotsman, E.; Levin, E.; Maor, U.; Tapia, S.

    2016-04-01

    In this paper we continue our program to construct a model for high energy soft interactions, based on the CGC/saturation approach. We demonstrate that in our model, which describes diffractive physics as well as multiparticle production at high energy, the density variation mechanism leads to the value of v2 , which is about 60%-70% of the measured v2 . Bearing in mind that in the CGC/saturation approach there are two other mechanisms present, Bose enhancement in the wave function and local anisotropy, we believe that the azimuthal long range rapidity correlations in proton-proton collisions stem from the CGC/saturation physics, and not from quark-gluon plasma production.

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  14. Physics with a High Intensity Proton Source at Fermilab: Project X Golden Book

    SciTech Connect

    Appel, Jeffrey; Asner, David; Bigi, Ikaros; Bryman, Douglas; Buras, Andrzej; Carena, Marcela Carosi, Roberto; Christian, Dave; Conrad, Janet; Diwan, Milind; Dukes, Craig; /Virginia U. /Fermilab

    2008-02-03

    Within the next ten years the Standard Model will likely have to be modified to encompass a wide range of newly discovered phenomena, new elementary particles, new symmetries, and new dynamics. These phenomena will be revealed through experiment with high energy particle accelerators, mainly the LHC. This will represent a revolution in our understanding of nature, and will either bring us closer to an understanding of all phenomena, through existing ideas such as supersymmetry to superstrings, or will cause us to scramble to find new ideas and a new sense of direction. We are thus entering a dramatic and important time in the quest to understand the fundamental laws of nature and their role in shaping the universe. The energy scales now probed by the Tevatron, of order hundreds of GeV, will soon be subsumed by the LHC and extended up to a few TeV. We expect the unknown structure of the mysterious symmetry breaking of the Standard Model to be revealed. We will then learn the answer to a question that has a fundamental bearing upon our own existence: 'What is the origin of mass?' All modern theories of 'electroweak symmetry breaking' involve many new particles, mainly to provide a 'naturalness' rationale for the weak scale. Supersymmetry (SUSY) represents extra (fermionic) dimensions of space, leading to a doubling of the number of known elementary particles and ushering in many additional new particles and phenomena associated with the various symmetry breaking sectors. The possibility of additional bosonic dimensions of space would likewise usher in an even greater multitude of new states and new phenomena. Alternatively, any new spectroscopy may indicate new principles we have not yet anticipated, and we may see new strong forces and/or a dynamical origin of mass. The wealth of new particles, parameters, CP-phases, and other phenomena carries important implications for precision quark flavor physics experiments that are uniquely sensitive probes of new phenomena

  15. High-energy proton imaging for biomedical applications

    PubMed Central

    Prall, M.; Durante, M.; Berger, T.; Przybyla, B.; Graeff, C.; Lang, P. M.; LaTessa, C.; Shestov, L.; Simoniello, P.; Danly, C.; Mariam, F.; Merrill, F.; Nedrow, P.; Wilde, C.; Varentsov, D.

    2016-01-01

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allows imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. Tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics. PMID:27282667

  16. High-energy proton imaging for biomedical applications

    DOE PAGESBeta

    Prall, Matthias; Durante, Marco; Berger, Thomas; Przybyla, B.; Graeff, C.; Lang, Phillipp M.; LaTessa, Ciara; Shestov, Less; Simoniello, P.; Danly, Christopher R.; et al

    2016-06-10

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allowsmore » imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. As a result, tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics.« less

  17. High-energy proton imaging for biomedical applications

    NASA Astrophysics Data System (ADS)

    Prall, M.; Durante, M.; Berger, T.; Przybyla, B.; Graeff, C.; Lang, P. M.; Latessa, C.; Shestov, L.; Simoniello, P.; Danly, C.; Mariam, F.; Merrill, F.; Nedrow, P.; Wilde, C.; Varentsov, D.

    2016-06-01

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allows imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. Tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics.

  18. High-energy proton imaging for biomedical applications.

    PubMed

    Prall, M; Durante, M; Berger, T; Przybyla, B; Graeff, C; Lang, P M; LaTessa, C; Shestov, L; Simoniello, P; Danly, C; Mariam, F; Merrill, F; Nedrow, P; Wilde, C; Varentsov, D

    2016-01-01

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allows imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. Tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics. PMID:27282667

  19. Narrow Energy Spread Protons and Ions from High-Intensity, High-Contrast Laser Solid Target Interactions

    SciTech Connect

    Dollar, Franklin; Matsuoka, Takeshi; McGuffey, Christopher; Bulanov, Stepan S.; Chvykov, Vladimir; Kalintchenko, Galina; Thomas, Alec G. R.; Willingale, Louise; Yanovsky, Victor; Maksimchuk, Anatoly; Krushelnick, Karl; Davis, Jack; Petrov, George

    2010-11-04

    Recent simulations show that an idealized, high intensity, short pulse laser can generate quasi-monoenergetic proton beams with energies over 100 MeV in an interaction with a thin film. However, most short pulse laser facilities with sufficient intensity have difficulty controlling the nanosecond and picosecond contrast necessary to realize such a regime. Experiments were performed to investigate proton and ion acceleration from a high contrast, short pulse laser by employing dual plasma mirrors along with a deformable mirror at the HERCULES laser facility at the Center for Ultrafast Optical Sciences, University of Michigan. Plasma mirrors were characterized, allowing a 50% throughput with an intensity contrast increase of 105. The focal spot quality was also exceptional, showing a 1.1 micron full width at half maximum (FWHM) focal diameter. Experiments were done using temporally cleaned 30 TW, 32 fs pulses to achieve an intensity of up to 10{sup 21} Wcm{sup -2} on Si{sub 3}N{sub 4} and Mylar targets with thicknesses ranging 50 nm to 13 microns. Proton beams with energy spreads below 2 MeV were observed from all thicknesses, peaking with energies up to 10.3 MeV and an energy spread of 0.8 MeV. Similar narrow energy spreads were observed for oxygen, nitrogen, and carbon at the silicon nitride thickness of 50 nm with energies up to 24 MeV with an energy spread of 3 MeV, whereas the energy spread is greatly increased at a larger thickness. Maximum energies were confirmed with CR39 track detectors, while a Thomson ion spectrometer was used to gauge the monoenergetic nature of the beam.

  20. High-energy protons from submicron-sized targets

    SciTech Connect

    Bychenkov, V. Yu.; Govras, E. A.; Brantov, A. V.; Popov, K. I.

    2012-07-11

    Improving of intensity contrast ratio of intense short laser pulses is making it possible to use submicron-sized targets, both spherical and plane, in the interest of proton acceleration for different applications. The way of improving of the ion beam quality is utilization of targets with two ion species - heavy ions (majority) and light ions, e.g. protons, (minority). Two different approaches, analytical theory and particle-in-cell simulations (PIC) are presented for studying the characteristics of laser-triggered ions due to the Coulomb-like mechanism of particle acceleration from submicron-sized targets. The comparative analysis of explosions of heterogeneous (layered) and homogeneously mixed targets for production of best quality ion bunches has been performed. We also found the regime of anisotropic proton acceleration from spherical targets with light and heavy ions relevant to the experiments with submicron-diameter droplets from water spray target irradiated by an ultrashort intense laser pulse.

  1. Internal spin structure of the proton from high energy polarized e-p scattering

    SciTech Connect

    Hughes, V.W.; Baum, G.; Bergstroem, M.R.

    1981-02-01

    A review is given of experimental knowledge of the spin dependent structure functions of the proton, which is based on inclusive high energy scattering of longitudinal polarized electrons by longitudinally polarized protons in both the deep inelastic and resonance regions, and includes preliminary results from our most recent SLAC experiment. Implications for scaling, sum rules, models of proton structure, and the hyperfine structure interval in hydrogen are given. Possible future directions of research are indicated.

  2. Proton Structure in High-Energy High-Multiplicity p-p Collisions

    NASA Astrophysics Data System (ADS)

    Głazek, Stanisław D.; Kubiczek, Patryk

    2016-06-01

    A few-body proton image, expected to be derivable from QCD in the renormalization group procedure for effective particles, is used within the Monte Carlo Glauber model to calculate the anisotropy coefficients in the initial collision-state of matter in high-energy high-multiplicity proton-proton interaction events. We estimate the ridge-like correlations in the final hadronic state by assuming their proportionality to the initial collision-state anisotropy. In our estimates, some distinct few-body proton structures appear capable of accounting for the magnitude of p-p ridge effect, with potentially discernible differences in dependence on multiplicity.

  3. Relations Between Microwave Bursts and Near-Earth High-Energy Proton Enhancements and Their Origin

    NASA Astrophysics Data System (ADS)

    Grechnev, V. V.; Kiselev, V. I.; Meshalkina, N. S.; Chertok, I. M.

    2015-10-01

    We further study the relations between parameters of bursts at 35 GHz recorded with the Nobeyama Radio Polarimeters during 25 years and solar proton events (Grechnev et al. in Publ. Astron. Soc. Japan 65, S4, 2013a). Here we address the relations between the microwave fluences at 35 GHz and near-Earth proton fluences above 100 MeV to find information on their sources and evaluate their diagnostic potential. The correlation between the microwave and proton fluences is pronouncedly higher than between their peak fluxes. This probably reflects a dependence of the total number of protons on the duration of the acceleration process. In events with strong flares, the correlation coefficients of high-energy proton fluences with microwave and soft X-ray fluences are higher than those with the speeds of coronal mass ejections. The results indicate a statistically larger contribution of flare processes to high-energy proton fluxes. Acceleration by shock waves seems to be less important at high energies in events associated with strong flares, although its contribution is probable and possibly prevails in weaker events. The probability of a detectable proton enhancement was found to directly depend on the peak flux, duration, and fluence of the 35 GHz burst, while the role of the Big Flare Syndrome might have been overestimated previously. Empirical diagnostic relations are proposed.

  4. Measurement of high energy resolution inelastic proton scattering at and close to zero degrees

    NASA Astrophysics Data System (ADS)

    Tamii, A.; Fujita, Y.; Matsubara, H.; Adachi, T.; Carter, J.; Dozono, M.; Fujita, H.; Fujita, K.; Hashimoto, H.; Hatanaka, K.; Itahashi, T.; Itoh, M.; Kawabata, T.; Nakanishi, K.; Ninomiya, S.; Perez-Cerdan, A. B.; Popescu, L.; Rubio, B.; Saito, T.; Sakaguchi, H.; Sakemi, Y.; Sasamoto, Y.; Shimbara, Y.; Shimizu, Y.; Smit, F. D.; Tameshige, Y.; Yosoi, M.; Zenhiro, J.

    2009-07-01

    Measurements of inelastic proton scattering with high energy resolution at forward scattering angles including 0∘ are described. High-resolution halo-free beams were accelerated by the cyclotron complex at the Research Center for Nuclear Physics. Instrumental background events were minimized using the high-quality beam. The remaining instrumental background events were eliminated by applying a background subtraction method. As a result, clean spectra were obtained even for a heavy target nucleus such as Pb208. A high energy resolution of 20 keV (FWHM) and a scattering angle resolution of ±0.6∘ were achieved at an incident proton energy of 295 MeV.

  5. Ion Desorption Stability in Superconducting High Energy Physics Proton Colliders

    SciTech Connect

    Turner, W.C.

    1995-05-29

    In this paper we extend our previous analysis of cold beam tube vacuum in a superconducting proton collider to include ion desorption in addition to thermal desorption and synchrotron radiation induced photodesorption. The new ion desorption terms introduce the possibility of vacuum instability. This is similar to the classical room temperature case but now modified by the inclusion of ion desorption coefficients for cryosorbed (physisorbed) molecules which can greatly exceed the coefficients for tightly bound molecules. The sojourn time concept for physisorbed H{sub 2} is generalized to include photodesorption and ion desorption as well as the usually considered thermal desorption. The ion desorption rate is density dependent and divergent so at the onset of instability the sojourn time goes to zero. Experimental data are used to evaluate the H{sub 2} sojourn time for the conditions of the Large Hadron Collider (LHC) and the situation is found to be stable. The sojourn time is dominated by photodesorption for surface density s(H{sub 2}) less than a monolayer and by thermal deposition for s(H{sub 2}) greater than a monolayer. For a few percent of a monolayer, characteristic of a beam screen, the photodesorption rate exceeds ion desorption rate by more than two orders of magnitude. The photodesorption rate corresponds to a sojourn time of approximately 100 sec. The paper next turns to the evaluation of stability margins and inclusion of gases heavier than H{sub 2} (CO, CO{sub 2} and CH{sub 4}), where ion desorption introduces coupling between molecular species. Stability conditions are worked out for a simple cold beam tube, a cold beam tube pumped from the ends and a cold beam tube with a co-axial perforated beam screen. In each case a simple inequality for stability of a single component is replaced by a determinant that must be greater than zero for a gas mixture. The connection with the general theory of feedback stability is made and it is shown that the gains

  6. Measuring the strong electrostatic and magnetic fields with proton radiography for ultra-high intensity laser channeling on fast ignition

    SciTech Connect

    Uematsu, Y.; Iwawaki, T.; Habara, H. Tanaka, K. A.; Ivancic, S.; Theobald, W.; Lei, A. L.

    2014-11-15

    In order to investigate the intense laser propagation and channel formation in dense plasma, we conducted an experiment with proton deflectometry on the OMEGA EP Laser facility. The proton image was analyzed by tracing the trajectory of mono-energetic protons, which provides understanding the electric and magnetic fields that were generated around the channel. The estimated field strengths (E ∼ 10{sup 11} V/m and B ∼ 10{sup 8} G) agree with the predictions from 2D-Particle-in-cell (PIC) simulations, indicating the feasibility of the proton deflectometry technique for over-critical density plasma.

  7. Measuring the strong electrostatic and magnetic fields with proton radiography for ultra-high intensity laser channeling on fast ignitiona)

    NASA Astrophysics Data System (ADS)

    Uematsu, Y.; Ivancic, S.; Iwawaki, T.; Habara, H.; Lei, A. L.; Theobald, W.; Tanaka, K. A.

    2014-11-01

    In order to investigate the intense laser propagation and channel formation in dense plasma, we conducted an experiment with proton deflectometry on the OMEGA EP Laser facility. The proton image was analyzed by tracing the trajectory of mono-energetic protons, which provides understanding the electric and magnetic fields that were generated around the channel. The estimated field strengths (E ˜ 1011 V/m and B ˜ 108 G) agree with the predictions from 2D-Particle-in-cell (PIC) simulations, indicating the feasibility of the proton deflectometry technique for over-critical density plasma.

  8. Measuring the strong electrostatic and magnetic fields with proton radiography for ultra-high intensity laser channeling on fast ignition.

    PubMed

    Uematsu, Y; Ivancic, S; Iwawaki, T; Habara, H; Lei, A L; Theobald, W; Tanaka, K A

    2014-11-01

    In order to investigate the intense laser propagation and channel formation in dense plasma, we conducted an experiment with proton deflectometry on the OMEGA EP Laser facility. The proton image was analyzed by tracing the trajectory of mono-energetic protons, which provides understanding the electric and magnetic fields that were generated around the channel. The estimated field strengths (E ∼ 10(11) V/m and B ∼ 10(8) G) agree with the predictions from 2D-Particle-in-cell (PIC) simulations, indicating the feasibility of the proton deflectometry technique for over-critical density plasma. PMID:25430358

  9. Single event upset and charge collection measurements using high energy protons and neutrons

    SciTech Connect

    Normand, E.; Oberg, D.L.; Wert, J.L.; Ness, J.D.; Majewski, P.P. ); Wender, S.; Gavron, A. )

    1994-12-01

    RAMs, microcontrollers and surface barrier detectors were exposed to beams of high energy protons and neutrons to measure the induced number of upsets as well as energy deposition. The WNR facility at Los Alamos provided a neutron spectrum similar to that of the atmospheric neutrons. Its effect on devices was compared to that of protons with energies of 200, 400, 500, and 800 MeV. Measurements indicate that SEU cross sections for 400 MeV protons are similar to those induced by the atmospheric neutron spectrum.

  10. 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.

  11. Measurements of the proton-air cross section with high energy cosmic ray experiments

    NASA Astrophysics Data System (ADS)

    Abbasi, Rasha

    2016-07-01

    Detecting Ultra High Energy Cosmic Rays (UHECRs) enables us to measure the proton-air inelastic cross section σinel p-air at energies that we are unable to access with particle accelerators. The proton-proton cross section σp-p is subsequently inferred from the proton-air cross section at these energies. UHECR experiments have been reportingon the proton-air inelastic cross section starting with the Fly's Eye in 1984 at √s =30 TeV and ending with the most recent result of the Telescope Array experiment at √s = 95 TeV in 2015. In this proceeding, I will summarize the most recent experimental results on the σinel p-air measurements from the UHECR experiments.

  12. Hole-boring radiation pressure acceleration as a basis for producing high-energy proton bunches

    NASA Astrophysics Data System (ADS)

    Robinson, A. P. L.; Trines, R. M. G. M.; Dover, N. P.; Najmudin, Z.

    2012-11-01

    The production of high-energy protons by the ‘hole-boring’ radiation pressure acceleration (HB-RPA) mechanism of laser-driven ion acceleration is examined in the case where the plasma has a density less than a0nc in 2D. Previously this was examined in 1D (Robinson 2011 Phys. Plasmas 18 056701) and was motivated by previous predictions of the non-linear criterion for an ultra-intense laser pulse to penetrate a dense plasma. By reducing the density well below a0nc the proton energies achieved increases considerably, thus leading to proton energies >100 MeV at laser intensities close to current capabilities. The results show that good quality proton beams with proton energies >100 MeV can be obtained via HB-RPA using targets with densities in the range 12-20nc and laser intensities in the range 5 × 1021-3 × 1022 W cm-2.

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

  14. Results on damage induced by high-energy protons in LYSO calorimeter crystals

    NASA Astrophysics Data System (ADS)

    Dissertori, G.; Luckey, D.; Nessi-Tedaldi, F.; Pauss, F.; Quittnat, M.; Wallny, R.; Glaser, M.

    2014-05-01

    Lutetium-Yttrium Orthosilicate doped with Cerium (LYSO), as a bright scintillating crystal, is a candidate for calorimetry applications in strong ionising-radiation fields and large high-energy hadron fluences are expected at the CERN Large Hadron Collider after the planned High-Luminosity upgrade. There, proton-proton collisions will produce fast hadron fluences up to ~ 5 ×1014cm-2 in the large-rapidity regions of the calorimeters. The performance of LYSO has been investigated, after exposure to different fluences of 24 GeV c-1 protons. Measured changes in optical transmission as a function of proton fluence are presented, and the evolution over time due to spontaneous recovery at room temperature is studied. The activation of materials will also be an issue in the described environment. Studies of the ambient dose induced by LYSO and its evolution with time, in comparison with other scintillating crystals, have also been performed through measurements and FLUKA simulations.

  15. A Nuclear Interaction Model for Understanding Results of Single Event Testing with High Energy Protons

    NASA Technical Reports Server (NTRS)

    Culpepper, William X.; ONeill, Pat; Nicholson, Leonard L.

    2000-01-01

    An internuclear cascade and evaporation model has been adapted to estimate the LET spectrum generated during testing with 200 MeV protons. The model-generated heavy ion LET spectrum is compared to the heavy ion LET spectrum seen on orbit. This comparison is the basis for predicting single event failure rates from heavy ions using results from a single proton test. Of equal importance, this spectra comparison also establishes an estimate of the risk of encountering a failure mode on orbit that was not detected during proton testing. Verification of the general results of the model is presented based on experiments, individual part test results, and flight data. Acceptance of this model and its estimate of remaining risk opens the hardware verification philosophy to the consideration of radiation testing with high energy protons at the board and box level instead of the more standard method of individual part testing with low energy heavy ions.

  16. The Impact of Intrinsic Heavy Quark Distributions in the Proton on New Physics Searches at the High Intensity Frontier

    SciTech Connect

    Brodsky, Stanley; Gardner, Susan; /Kentucky U.

    2012-02-16

    The possibility of an intense proton facility, at 'Project X' or elsewhere, will provide many new opportunities for searches for physics beyond the Standard Model. A Project X can serve a yet broader role in the search for new physics, and in this note we highlight the manner in which thus-enabled studies of the flavor structure of the proton, particularly of its intrinsic heavy quark content, facilitate other direct and indirect searches for new physics. Intrinsic heavy quarks in both light and heavy hadrons play a key role in searches for physics BSM with hadrons - and their study at the Intensity Frontier may prove crucial to establishing its existence.

  17. Interaction of High-Energy Proton Beam with a Thin Target and Multiplicities of Neutron

    SciTech Connect

    Demirkol, I.; Tatar, M.; Safak, M. S.; Arasoglu, A.; Tel, E.

    2007-04-23

    An important ingredient in the performance of accelerator driven systems for energy production, waste transmutation and other applications are the number of spallation neutrons produced per incident proton. The neutron multiplicities, angular and energy distributions are usually calculated using simulation codes. We have presented multiplicities of the neutrons emitted in the interaction of a high-energy proton (1500 MeV) with a thin target Pb, Bi. In this study we have used the code ISABEL to calculate multiplicities of the neutron emitted. The results obtained have been compared with the available data.

  18. Possibilities of polarized protons in Sp anti p S and other high energy hadron colliders

    SciTech Connect

    Courant, E.D.

    1984-01-01

    The requirements for collisions with polarized protons in hadron colliders above 200 GeV are listed and briefly discussed. Particular attention is given to the use of the ''Siberan snake'' to eliminate depolarizing resonances, which occur when the spin precession frequency equals a frequency contained in the spectrum of the field seen by the beam. The Siberian snake is a device which makes the spin precession frequency essentially constant by using spin rotators, which precess the spin by 180/sup 0/ about either the longitudinal or transverse horizontal axis. It is concluded that operation with polarized protons should be possible at all the high energy hadron colliders. (LEW)

  19. High energy proton irradiation induced pinning centers in Bi-2212 and Bi-2223 superconductors

    SciTech Connect

    Willis, J.O.; Safar, H.; Cho, J.H.

    1995-12-01

    Bi-2212 single crystals and Bi-2223/Ag-sheathed tapes were irradiated with high energy protons. TEM images reveal the production of randomly oriented (splayed) columnar defects with an amorphous core of {approximately}10 nm diameter caused by the fissioning of Bi nuclei. The critical current density J{sub c} and irreversibility line both substantially increased with the proton dose for both crystals and tapes, especially for the magnetic field parallel to the c axis. An irradiated tape had a J{sub c} value {approximately}100 times greater than that of an unirradiated one at 1 T and 75 K.

  20. Centrality-dependent forward J/ψ production in high energy proton-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Ducloué, B.; Lappi, T.; Mäntysaari, H.

    2016-03-01

    Forward J/ψ production and suppression in high energy proton-nucleus collisions can be an important probe of gluon saturation. In an earlier work we studied this process in the Color Glass Condensate framework and showed that using the Glauber approach to extrapolate the dipole cross section of a proton to a nucleus leads to results closer to experimental data than previous calculations in this framework. Here we investigate the centrality dependence of the nuclear suppression in this model and show a comparison of our results with recent LHC data.

  1. Laser-induced generation of ultraintense proton beams for high energy-density science

    SciTech Connect

    Badziak, J.; Jablonski, S.; Parys, P.; Rosinski, M.; Suchanska, R.; Wolowski, J.; Antici, P.; Fuchs, J.; Mancic, A.; Szydlowski, A.

    2008-06-24

    Basic properties of high-current high-intensity ion beam generation using laser-induced skin-layer ponderomotive acceleration (SLPA) are discussed. The results of a recent experiment, in which 0.35-ps laser pulse of intensity up to 2x10{sup 19} W/cm{sup 2} irradiated a thin (1-3 {mu}m) PS (plastic) or Au/PS target (PS covered by 0.1-0.2 {mu}m Au front layer), are presented. It is shown that multi-MA proton beams of current densities >1 TA/cm{sup 2} and intensities > 10{sup 18} W/cm{sup 2} at the source can be produced when the laser-target interaction conditions approach the SLPA requirements. The proton beam parameters as well as the laser-protons energy conversion efficiency substantially depend on the target structure and can be significantly increased with the use of a double-layer Au/PS target. A prospect for the application of SLPA-driven proton beams in ICF fast ignition research is outlined.

  2. High-energy proton radiation damage of high-purity germanium detectors

    NASA Technical Reports Server (NTRS)

    Pehl, R. H.; Varnell, L. S.; Metzger, A. E.

    1978-01-01

    Quantitative studies of radiation damage in high-purity germanium gamma-ray detectors due to high-energy charged particles have been carried out; two 1.0 cm thick planar detectors were irradiated by 6 GeV/c protons. Under proton bombardment, degradation in the energy resolution was found to begin below 7 x 10 to the 7th protons/sq cm and increased proportionately in both detectors until the experiment was terminated at a total flux of 5.7 x 10 to the 8th protons/sq cm, equivalent to about a six year exposure to cosmic-ray protons in space. At the end of the irradiation, the FWHM resolution measured at 1332 keV stood at 8.5 and 13.6 keV, with both detectors of only marginal utility as a spectrometer due to the severe tailing caused by charge trapping. Annealing these detectors after proton damage was found to be much easier than after neutron damage.

  3. Laser-driven high-energy proton beam with homogeneous spatial profile from a nanosphere target

    NASA Astrophysics Data System (ADS)

    Margarone, D.; Kim, I. J.; Psikal, J.; Kaufman, J.; Mocek, T.; Choi, I. W.; Stolcova, L.; Proska, J.; Choukourov, A.; Melnichuk, I.; Klimo, O.; Limpouch, J.; Sung, J. H.; Lee, S. K.; Korn, G.; Jeong, T. M.

    2015-07-01

    A high-energy, high-yield proton beam with a good homogeneous profile has been generated from a nanosphere target irradiated by a short (30-fs), intense (7 ×1020 W /cm2 ) laser pulse. A maximum proton energy of 30 MeV has been observed with a high proton number of 7 ×1010 in the energy range 5-30 MeV. A homogeneous spatial profile with a uniformity (standard deviation from an average value within 85% beam area) of 15% is observed with the nanosphere dielectric target. Particle-in-cell simulations show the enhancement of proton cutoff energy and proton number with the nanosphere target and reveal that the homogeneous beam profile is related with a broadened angular distribution of hot electrons, which is initiated by the nanosphere structure. The homogeneous spatial properties obtained with the nanosphere target will be advantageous in developing laser-driven proton sources for practical applications in which high-quality beams are required.

  4. 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.

  5. High-intensity polarized H-(proton), deuteron and 3He++ion source development at BNL.

    SciTech Connect

    Zelenski,A.

    2008-06-23

    New techniques for the production of polarized electron, H{sup -} (proton), D (D+) and {sup 3}H{sup ++} ion beams are discussed. Feasibility studies of these techniques are in progress at BNL. An Optically Pumped Polarized H{sup -} Ion Source (OPPIS) delivers beam for polarization studies in RHIC. The polarized deuteron beam will be required for the deuteron Electron Dipole Moment (EDM) experiment, and the {sup 3}H{sup ++} ion beam is a part of the experimental program for the future eRHIC (Electron Ion) collider.

  6. Innermost Van Allen Radiation Belt for High Energy Protons at Saturn

    NASA Technical Reports Server (NTRS)

    Cooper, John F.

    2008-01-01

    The high energy proton radiation belts of Saturn are energetically dominated by the source from cosmic ray albedo neutron decay (CRAND), trapping of protons from beta decay of neutrons emitted from galactic cosmic ray nuclear interactions with the main rings. These belts were originally discovered in wide gaps between the A-ring, Janus/Epimetheus, Mimas, and Enceladus. The narrow F and G rings significant affected the CRAND protons but did not produce total depletion. Voyager 2 measurements subsequently revealed an outermost CRAND proton belt beyond Enceladus. Although the source rate is small, the trapping times limited by radial magnetospheric diffusion are very long, about ten years at peak measured flux inwards of the G ring, so large fluxes can accumulate unless otherwise limited in the trapping region by neutral gas, dust, and ring body interactions. One proposed final extension of the Cassini Orbiter mission would place perikrone in a 3000-km gap between the inner D ring and the upper atmosphere of Saturn. Experience with CRAND in the Earth's inner Van Allen proton belt suggests that a similar innermost belt might be found in this comparably wide region at Saturn. Radial dependence of magnetospheric diffusion, proximity to the ring neutron source, and northward magnetic offset of Saturn's magnetic equator from the ring plane could potentially produce peak fluxes several orders of magnitude higher than previously measured outside the main rings. Even brief passes through such an intense environment of highly penetrating protons would be a significant concern for spacecraft operations and science observations. Actual fluxes are limited by losses in Saturn's exospheric gas and in a dust environment likely comparable to that of the known CRAND proton belts. The first numerical model of this unexplored radiation belt is presented to determine limits on peak magnitude and radial profile of the proton flux distribution.

  7. The Quest for Spinning Glue in High-Energy Polarized Proton-Proton Collisions at RHIC

    SciTech Connect

    Surrow, Bernd

    2007-10-26

    The STAR experiment at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is carrying out a spin physics program colliding transverse or longitudinal polarized proton beams at {radical}(s) = 200-500 GeV to gain a deeper insight into the spin structure and dynamics of the proton. These studies provide fundamental tests of Quantum Chromodynamics (QCD).One of the main objectives of the STAR spin physics program is the determination of the polarized gluon distribution function through a measurement of the longitudinal double-spin asymmetry, A{sub LL}, for various processes. Recent results will be shown on the measurement of A{sub LL} for inclusive jet production, neutral pion production and charged pion production at {radical}(s) = 200 GeV.

  8. Regolith Biological Shield for a Lunar Outpost from High Energy Solar Protons

    SciTech Connect

    Pham, Tai T.; El-Genk, Mohamed S.

    2008-01-21

    Beyond Earth atmosphere, natural space radiation from Galactic Cosmic Rays and Solar Energetic Protons (SEPs) represents a significant hazard to both manned and robotic missions. For lunar settlements, protecting astronauts from SEPs is a key safety issue that needs to be addressed by identifying appropriate shielding materials. This paper investigates the interaction of SEPs with the lunar regolith, and quantifies the effectiveness of the regolith as a biological shield for a human habitat, compared to aluminum, presently the standard shielding material. Also calculated is the shielding thickness to reduce the dose in the habitat to those recommended by International Radiation Protection Committee and by NASA for operation on the international space station. The present calculations are for the most energetic solar event of February 1956, which included high energy protons up to 1000 MeV. Results show that the lunar regolith is as effective as aluminum for shielding lunar outposts. A large thickness of the regolith ({approx}30 g/cm{sup 2}) would be needed to reduce the dose in the habitat from high energy protons below the 30 days flight crew limit of 25 Rem (or 250 mSv) and significantly more shielding would be needed ({approx}150 g/cm{sup 2}) to reduce the dose down to the limit for radiation workers of 5 Rem (or 50 mSv)

  9. Regolith Biological Shield for a Lunar Outpost from High Energy Solar Protons

    NASA Astrophysics Data System (ADS)

    Pham, Tai T.; El-Genk, Mohamed S.

    2008-01-01

    Beyond Earth atmosphere, natural space radiation from Galactic Cosmic Rays and Solar Energetic Protons (SEPs) represents a significant hazard to both manned and robotic missions. For lunar settlements, protecting astronauts from SEPs is a key safety issue that needs to be addressed by identifying appropriate shielding materials. This paper investigates the interaction of SEPs with the lunar regolith, and quantifies the effectiveness of the regolith as a biological shield for a human habitat, compared to aluminum, presently the standard shielding material. Also calculated is the shielding thickness to reduce the dose in the habitat to those recommended by International Radiation Protection Committee and by NASA for operation on the international space station. The present calculations are for the most energetic solar event of February 1956, which included high energy protons up to 1000 MeV. Results show that the lunar regolith is as effective as aluminum for shielding lunar outposts. A large thickness of the regolith (~30 g/cm2) would be needed to reduce the dose in the habitat from high energy protons below the 30 days flight crew limit of 25 Rem (or 250 mSv) and significantly more shielding would be needed (~150 g/cm2) to reduce the dose down to the limit for radiation workers of 5 Rem (or 50 mSv).

  10. Spin-spin correlations in proton-proton collisions at high energy and threshold enhancements

    SciTech Connect

    de Teramond, G.F.

    1988-05-01

    The striking effects in the spin structure observed in elastic proton collisions and the Nuclear Transparency phenomenon recently discovered at BNL are described in terms of heavy quark threshold enhancements. The deviations from scaling laws and the broadening of the angular distributions at resonance are also consistent with the introduction of new degrees of freedom in the pp system. This implies new s-channel physics. Predictions are given for the spin effects in pp collisions near 18.5 GeV/c at large p/sub T//sup 2/ where new measurements are planned. 9 refs., 4 figs.

  11. High energy proton-proton elastic scattering at the Large Hadron Collider and nucleon structure

    NASA Astrophysics Data System (ADS)

    Luddy, Richard Joseph

    To gain insight into the structure of the nucleon, we pursue the development of the phenomenological model of Islam et al. (IIFS model) for high energy elastic pp and p¯p scattering. We determine the energy dependence of the parameters of the IIFS model using the available elastic differential cross section data from SPS Collider and Tevatron and the known asymptotic behavior of sigmatot (s) and rho(s) from dispersion relation calculations and more recent analyses of Cudell et al. (COMPETE Collaboration). Next, we incorporate a high energy elastic valence quark-quark scattering amplitude into the model based on BFKL pomeron to describe small impact parameter (large | t|) pp collisions. Finally, we predict the pp elastic differential cross section at the unprecedented c.m. energy of s = 14.0 TeV at the Large Hadron Collider (LHC). This prediction assumes crucial significance---because of an approved experiment at LHC: TOTal and Elastic Measurement (TOTEM). The TOTEM group plans to measure pp elastic dsigma/dt at 14.0 TeV all the way from momentum transfer |t| = 0 to |t| ≃ 10 GeV 2. Their measurement will stringently test not only the diffraction and o-exchange descriptions of the original IIFS model, but also the additional valence quark-quark scattering contribution that we find to be dominant for large |t|. Successful quantitative verification of the predicted dsigma/dt will mean that our picture of the nucleon with an outer cloud of qq¯ condensed ground state, an inner core of topological baryonic charge, and a still smaller core of massless valence quarks provides a realistic description of nucleon structure.

  12. Optimum angle-cut of collimator for dense objects in high-energy proton radiography

    NASA Astrophysics Data System (ADS)

    Hai-Bo, Xu; Na, Zheng

    2016-02-01

    The use of minus identity lenses with an angle-cut collimator can achieve high contrast images in high-energy proton radiography. This article presents the principles of choosing the angle-cut aperture of the collimator for different energies and objects. Numerical simulation using the Monte Carlo code Geant4 has been implemented to investigate the entire radiography for the French test object. The optimum angle-cut apertures of the collimators are also obtained for different energies. Supported by NSAF (11176001) and Science and Technology Developing Foundation of China Academy of Engineering Physics (2012A0202006)

  13. Development of an abort gap monitor for high-energy proton rings

    SciTech Connect

    Beche, Jean-Francois; Byrd, John; De Santis, Stefano; Denes, Peter; Placidi, Massimo; Turner, William; Zolotorev, Max

    2004-05-03

    The fill pattern in proton synchrotrons usually features an empty gap, longer than the abort kicker raise time, for machine protection. This gap is referred to as the ''abort gap'' and any particles, which may accumulate in it due to injection errors and diffusion between RF buckets, would be lost inside the ring, rather than in the beam dump, during the kicker firing. In large proton rings, due to the high energies involved, it is vital to monitor the build up of charges in the abort gap with a high sensitivity. We present a study of an abort gap monitor based on a photomultiplier with a gated microchannel plate, which would allow for detecting low charge densities by monitoring the synchrotron radiation emitted. We show results of beam test experiments at the Advanced Light Source using a Hamamatsu 5916U MCP-PMT and compare them to the specifications for the Large Hadron Collider

  14. Synchrotron based proton drivers

    SciTech Connect

    Weiren Chou

    2002-09-19

    Proton drivers are the proton sources that produce intense short proton bunches. They have a wide range of applications. This paper discusses the proton drivers based on high-intensity proton synchrotrons. It gives a review of the high-intensity proton sources over the world and a brief report on recent developments in this field in the U.S. high-energy physics (HEP) community. The Fermilab Proton Driver is used as a case study for a number of challenging technical design issues.

  15. Study of the effects of high-energy proton beams on escherichia coli

    NASA Astrophysics Data System (ADS)

    Park, Jeong Chan; Jung, Myung-Hwan

    2015-10-01

    Antibiotic-resistant bacterial infection is one of the most serious risks to public health care today. However, discouragingly, the development of new antibiotics has progressed little over the last decade. There is an urgent need for alternative approaches to treat antibiotic-resistant bacteria. Novel methods, which include photothermal therapy based on gold nano-materials and ionizing radiation such as X-rays and gamma rays, have been reported. Studies of the effects of high-energy proton radiation on bacteria have mainly focused on Bacillus species and its spores. The effect of proton beams on Escherichia coli (E. coli) has been limitedly reported. Escherichia coli is an important biological tool to obtain metabolic and genetic information and is a common model microorganism for studying toxicity and antimicrobial activity. In addition, E. coli is a common bacterium in the intestinal tract of mammals. In this research, the morphological and the physiological changes of E. coli after proton irradiation were investigated. Diluted solutions of cells were used for proton beam radiation. LB agar plates were used to count the number of colonies formed. The growth profile of the cells was monitored by using the optical density at 600 nm. The morphology of the irradiated cells was observed with an optical microscope. A microarray analysis was performed to examine the gene expression changes between irradiated samples and control samples without irradiation. E coli cells have observed to be elongated after proton irradiation with doses ranging from 13 to 93 Gy. Twenty-two were up-regulated more than twofold in proton-irradiated samples (93 Gy) compared with unexposed one.

  16. Detecting cavitation in mercury exposed to a high-energy pulsed proton beam.

    PubMed

    Manzi, Nicholas J; Chitnis, Parag V; Holt, R Glynn; Roy, Ronald A; Cleveland, Robin O; Riemer, Bernie; Wendel, Mark

    2010-04-01

    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 muC will be reported on. Cavitation was initially detected for a beam charge of 0.082 muC by the presence of an acoustic emission approximately 250 mus 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 muC and higher, the lifetimes of the bubbles exceeded the reverberation time of the chamber ( approximately 300 mus), 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. PMID:20370004

  17. 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.

  18. Three-hadron angular correlations in high-energy proton-proton and nucleus-nucleus collisions from perturbative QCD

    SciTech Connect

    Ayala, Alejandro; Ortiz, Antonio; Paic, Guy; Jalilian-Marian, Jamal; Magnin, J.; Tejeda-Yeomans, Maria Elena

    2011-08-15

    We study three-hadron azimuthal angular correlations in high-energy proton-proton and central nucleus-nucleus collisions at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider at midrapidity. We use the leading-order parton matrix elements for 2{yields}3 processes and include the effect of parton energy loss in the quark-gluon plasma using the modified fragmentation function approach. For the case when the produced hadrons have either the same or not too different momenta, we observe two away-side peaks at 2{pi}/3 and 4{pi}/3. We consider the dependence of the angular correlations on energy loss parameters that have been used in studies of single inclusive hadron production at RHIC. Our results on the angular dependence of the cross section agree well with preliminary data by the PHENIX Collaboration. We comment on the possible contribution of 2{yields}3 processes to dihadron angular correlations and how a comparison of the two processes may help characterize the plasma further.

  19. A prediction model for bipolar RAMs in a high energy ion/proton environment

    NASA Technical Reports Server (NTRS)

    Myers, D. K.; Price, W. E.; Nichols, D. K.

    1981-01-01

    A model has been developed which predicts the relative susceptibility of bipolar RAMs to heavy ion and proton upset. During the course of evaluating this model, physical and electrical variations were also evaluated indicating that the minimum internal signal level is the primary upset susceptibility indicator. Unfortunately, all of the physical and electrical variations expected during a normal product development cycle are in direct opposition to improved high-energy particle upset tolerance. Hence, a trade-off between highly susceptible, low power (medium speed) devices must be made against the less susceptible, higher power (high speed) equivalent device, taking into account the systems trade-off with respect to system power, software, error correction procedures and/or circuit redundancy.

  20. Production of qq pairs in proton-nucleus collisions at high energies

    SciTech Connect

    Kovchegov, Yuri V.; Tuchin, Kirill

    2006-09-01

    We calculate production of quark-antiquark pairs in high energy proton-nucleus collisions both in the quasiclassical approximation of McLerran-Venugopalan model and including quantum small-x evolution. The resulting production cross section is explicitly expressed in terms of Glauber-Mueller multiple rescatterings in the classical case and in terms of dipole-nucleus scattering amplitude in the quantum evolution case. We generalize the result of [K. Tuchin, Phys. Lett. B 593, 66 (2004).] beyond the aligned jet configurations. We expand on the earlier results of Blaizot, Gelis and Venugopalan [J. P. Blaizot, F. Gelis, and R. Venugopalan, Nucl. Phys. A743, 57 (2004).] by deriving quark production cross section including quantum evolution corrections in rapidity intervals both between the quarks and the target and between the quarks and the projectile.

  1. Production of qq¯ pairs in proton-nucleus collisions at high energies

    NASA Astrophysics Data System (ADS)

    Kovchegov, Yuri V.; Tuchin, Kirill

    2006-09-01

    We calculate production of quark-antiquark pairs in high energy proton-nucleus collisions both in the quasiclassical approximation of McLerran-Venugopalan model and including quantum small-x evolution. The resulting production cross section is explicitly expressed in terms of Glauber-Mueller multiple rescatterings in the classical case and in terms of dipole-nucleus scattering amplitude in the quantum evolution case. We generalize the result of [K. Tuchin, Phys. Lett. B 593, 66 (2004).PYLBAJ0370-269310.1016/j.physletb.2004.04.057] beyond the aligned jet configurations. We expand on the earlier results of Blaizot, Gelis and Venugopalan [J. P. Blaizot, F. Gelis, and R. Venugopalan, Nucl. Phys. A743, 57 (2004).] by deriving quark production cross section including quantum evolution corrections in rapidity intervals both between the quarks and the target and between the quarks and the projectile.

  2. Intestinal microbiota reduces genotoxic endpoints induced by high-energy protons.

    PubMed

    Maier, Irene; Berry, David M; Schiestl, Robert H

    2014-01-01

    Ionizing space radiation causes oxidative DNA damage and triggers oxidative stress responses, and compromised DNA repair mechanisms can lead to increased risk of carcinogenesis. Young adult mice with developed innate and adaptive immune systems that harbored either a conventional intestinal microbiota (CM) or an intestinal microbiota with a restricted microbial composition (RM) were irradiated with a total dose of 1 Gy delivered by high-energy protons (2.5 GeV/n, LET = 0.2-2 keV/μm) or silicon or iron ions (850 MeV/n, LET ≈ 50 keV/μm and 1 GeV/n, LET = 150 keV/μm, respectively). Six hours after whole-body irradiation, acute chromosomal DNA lesions were observed for RM mice but not CM mice. High-throughput rRNA gene sequencing of intestinal mucosal bacteria showed that Barnesiella intestinihominis and unclassified Bacterodiales were significantly more abundant in male RM mice than CM mice, and phylotype densities changed in irradiated mice. In addition, Helicobacter hepaticus and Bacteroides stercoris were higher in CM than RM mice. Elevated levels of persistently phosphorylated γ-H2AX were observed in RM mice exposed to high-energy protons compared to nonirradiated RM mice, and they also were associated with a decrease of the antioxidant glutathione in peripheral blood measured at four weeks after irradiation. After radiation exposure, CM mice showed lower levels of γ-H2AX phosphorylation than RM mice and an increase in specific RM-associated phylotypes, indicating a down-regulating force on DNA repair by differentially abundant phylotypes in RM versus a radiation-sensitive complex CM. PMID:24397477

  3. Space charge effect of the high intensity proton beam during the resonance extraction for the Mu2e experiment at Fermilab

    SciTech Connect

    Park, Chong Shik; Amundson, James; Johnstone, John; Michelotti, Leo; Nagaslaev, Vladimir; Werkema, Steve; /Fermilab

    2011-03-01

    The proposed Mu2e experiment to search for direct {mu} {yields} e conversion at Fermilab plans slow, resonant extraction of a beam with 3 x 10{sup 12} protons from the Debuncher ring. Space charge of this high intensity beam is a critical factor, since it induces significant betatron tune spread and consequently affects resonance extraction processes, such as spill uniformity and beam losses. This study shows the multi-particle simulation results in the early stages of resonance extraction and spill uniformity in the presence of 2D and 3D space charge effects. We have presented the results of the third-integer resonance extraction in early stage for the Mu2e experiment in the presence of space charge effects. In order to track particles and to calculate self-consistent space charge effects, Synergia2 was used, which is capable of parallel computing. The space charge tune shift was computed and was reasonable value compared with the analytical calculation. Locations of the septum and Lambertson were chosen so that particles are kicked and extracted efficiently. The spill rates for with and without space charge effects were uniform, but should be improved for the early stage after the sextupole field ramping.

  4. EGRET High Energy Capability and Multiwavelength Flare Studies and Solar Flare Proton Spectra

    NASA Technical Reports Server (NTRS)

    Chupp, Edward L.

    1998-01-01

    The accomplishments of the participation in the Compton Gamma Ray Observatory Guest investigator program is summarized in this report. The work involved the study of Energetic Gamma Ray Experiment Telescope (EGRET)/Total Absorption Shower Counter(TASC) flare data. The specific accomplishments were the use of the accelerator neutron measurements obtained at the University of New Hampshire to verify the TASC response function and to modify the TASC fitting program to include a high energy neutron contribution, and to determine a high energy neutron contribution to the emissions from the 1991 June 11, solar flare. The next step in the analysis of this event was doing fits to the TASC energy-loss spectra as a function of time. A significant hardening of the solar proton spectrum over time was found for the flare. Further data was obtained from the Yohkoh HXT time histories and images for the 1991 October 27 flare. The results to date demonstrate that the TASC spectral analysis contributes crucial information on the particle spectrum interacting at the Sun. The report includes a paper accepted for publication, a draft of a paper to be delivered at the 26th International Cosmic Ray Conference and an abstract of a paper to be presented at the Meeting of the American Physical Society.

  5. Monte Carlo approach for hadron azimuthal correlations in high energy proton and nuclear collisions

    NASA Astrophysics Data System (ADS)

    Ayala, Alejandro; Dominguez, Isabel; Jalilian-Marian, Jamal; Magnin, J.; Tejeda-Yeomans, Maria Elena

    2012-09-01

    We use a Monte Carlo approach to study hadron azimuthal angular correlations in high-energy proton-proton and central nucleus-nucleus collisions at the BNL Relativistic Heavy Ion Collider energies at midrapidity. We build a hadron event generator that incorporates the production of 2→2 and 2→3 parton processes and their evolution into hadron states. For nucleus-nucleus collisions we include the effect of parton energy loss in the quark-gluon plasma using a modified fragmentation function approach. In the presence of the medium, for the case when three partons are produced in the hard scattering, we analyze the Monte Carlo sample in parton and hadron momentum bins to reconstruct the angular correlations. We characterize this sample by the number of partons that are able to hadronize by fragmentation within the selected bins. In the nuclear environment the model allows hadronization by fragmentation only for partons with momentum above a threshold pTthresh=2.4 GeV. We argue that one should treat properly the effect of those partons with momentum below the threshold, because their interaction with the medium may lead to showers of low-momentum hadrons along the direction of motion of the original partons as the medium becomes diluted.

  6. Isochoric heating of matter by laser-accelerated high-energy protons

    NASA Astrophysics Data System (ADS)

    Fuchs, Julien; Mancic, Ana; Robiche, Jerome; Antici, Patrizio; Lancia, Livia; Audebert, Patrick; Combis, Patrick; Renaudin, Patrick; Kimura, Tomoaki; Kodama, Ryosuke; Nakatsutsumi, Motoaki

    2008-04-01

    Producing matter at a high temperature (1-25 eV) and solid density is of prime interest for fundamental plasma physics or ICF. The use of laser-based high energy proton beams to achieve such state of matter is interesting since they are short (< 1 ps) and they deposit their energy volumetrically; thus can heat, before they expand, much thicker samples than allowed using laser-heating. We performed, using two intense short pulses of the LULI 100 TW facility, experiments to characterize the achieved state of matter, coupled to a detailed hydro-modeling. A laser-generated proton beam irradiated and heated a secondary target positioned after a vacuum gap. Three diagnostics were used: (i) 1D time-resolved optical self-emission of the heated target rear-surface at two wavelengths, (ii) time-resolved interferometry of a chirped probe beam reflecting off the heated target rear-surface, (iii) x-ray absorption spectroscopy through the heated target using a laser-produced backlighter detecting its Kα-edge softening.

  7. Temporal relationship between high-energy proton acceleration and magnetic field changes during solar flares

    NASA Astrophysics Data System (ADS)

    Kurt, Victoria; Yushkov, Boris

    Understanding of the association of the magnetic field evolution in the corona and the temporal evolution of electromagnetic emissions produced by the accelerated particles during a solar flare can provide information about the nature of the energy-release process and its location. Recent high-spatial-resolution observations in HXR, UV and radio emissions allow one to study in detail a structure of two-ribbon flare site. According to these observations, the flare process can be divided into two different intervals with different temporal evolution of morphological structure: loop contraction during impulsive phase and subsequent loop expansion. Оn the other hand, the appearance of high-energy protons (with energy >300 MeV - an energy threshold of the pion production) in the solar atmosphere can be revealed from an emerging pion-decay component of high-energy gamma-ray emission. The present work is based on comparison of measurements of high-energy gamma-rays performed with the SONG detector onboard the CORONAS-F mission and reported observations of magnetic field evolution, such as HXR foot points (FP) separation and flare shear temporal behavior, or motion of UV/radio loops. We reliably identified the pion-decay component of gamma-ray emission in the course of five events attended with suitable spatial observations, namely, 2001 August 25, 2002 August 24, 2003 October 28, 2003 October 29, and 2005 January 20, and determined its onset time. We found that in these events the pion-decay emission occurred when the distance between conjugated foot-points of flare loops ceased to decrease and began to increase, i.e. changed from shrinkage to expansion. This result leads to the conclusion that the most efficient proton acceleration up to >300 MeV coincided in time with the radical reconfiguration of the magnetic field in the flare site. Earlier we found that the pion-decay emission onset in the 2003 October 28 flare was close to the time of maximum change rate of the

  8. Intergalactic Magnetic Field and Arrival Direction of Ultra-High-Energy Protons

    NASA Astrophysics Data System (ADS)

    Ryu, Dongsu; Das, Santabrata; Kang, Hyesung

    2010-02-01

    We studied how the intergalactic magnetic field (IGMF) affects the propagation of super-Greisen-Zatsepin-Kuz'min (GZK) protons that originate from extragalactic sources within the local GZK sphere. To this end, we set up hypothetical sources of ultra-high-energy cosmic rays (UHECRs), virtual observers, and the magnetized cosmic web in a model universe constructed from cosmological structure formation simulations. We then arranged a set of reference objects mimicking active galactic nuclei (AGNs) in the local universe, with which correlations of simulated UHECR events are analyzed. With our model IGMF, the deflection angle between the arrival direction of super-GZK protons and the sky position of their actual sources is quite large with a mean value of langθrang ~ 15° and a median value of \\tilde{θ}˜ 7°-10°. On the other hand, the separation angle between the arrival direction and the sky position of nearest reference objects is substantially smaller with langSrang ~ 3fdg5-4°, which is similar to the mean angular distance in the sky to nearest neighbors among the reference objects. This is a direct consequence of our model that the sources, observers, reference objects, and the IGMF all trace the matter distribution of the universe. The result implies that extragalactic objects lying closest to the arrival direction of UHECRs are not necessarily their actual sources. With our model for the distribution of reference objects, the fraction of super-GZK proton events, whose closest AGNs are true sources, is less than 1/3. We discussed implications of our findings for correlation studies of real UHECR events.

  9. Multiple collision effects on the antiproton production by high energy proton (100 GeV - 1000 GeV)

    SciTech Connect

    Takahashi, Hiroshi; Powell, J.

    1987-01-01

    Antiproton production rates which take into account multiple collision are calculated using a simple model. Methods to reduce capture of the produced antiprotons by the target are discussed, including geometry of target and the use of a high intensity laser. Antiproton production increases substantially above 150 GeV proton incident energy. The yield increases almost linearly with incident energy, alleviating space charge problems in the high current accelerator that produces large amounts of antiprotons.

  10. Transmission calculation by empirical numerical model and Monte Carlo simulation in high energy proton radiography of thick objects

    NASA Astrophysics Data System (ADS)

    Zheng, Na; Xu, Hai-Bo

    2015-10-01

    An empirical numerical model that includes nuclear absorption, multiple Coulomb scattering and energy loss is presented for the calculation of transmission through thick objects in high energy proton radiography. In this numerical model the angular distributions are treated as Gaussians in the laboratory frame. A Monte Carlo program based on the Geant4 toolkit was developed and used for high energy proton radiography experiment simulations and verification of the empirical numerical model. The two models are used to calculate the transmission fraction of carbon and lead step-wedges in proton radiography at 24 GeV/c, and to calculate radial transmission of the French Test Object in proton radiography at 24 GeV/c with different angular cuts. It is shown that the results of the two models agree with each other, and an analysis of the slight differences is given. Supported by NSAF (11176001) and Science and Technology Developing Foundation of China Academy of Engineering Physics (2012A0202006)

  11. Production of Actinium-225 via High Energy Proton Induced Spallation of Thorium-232

    SciTech Connect

    Harvey, James T.; Nolen, Jerry; Vandergrift, George; Gomes, Itacil; Kroc, Tom; Horwitz, Phil; McAlister, Dan; Bowers, Del; Sullivan, Vivian; Greene, John

    2011-12-30

    The science of cancer research is currently expanding its use of alpha particle emitting radioisotopes. Coupled with the discovery and proliferation of molecular species that seek out and attach to tumors, new therapy and diagnostics are being developed to enhance the treatment of cancer and other diseases. This latest technology is commonly referred to as Alpha Immunotherapy (AIT). Actinium-225/Bismuth-213 is a parent/daughter alpha-emitting radioisotope pair that is highly sought after because of the potential for treating numerous diseases and its ability to be chemically compatible with many known and widely used carrier molecules (such as monoclonal antibodies and proteins/peptides). Unfortunately, the worldwide supply of actinium-225 is limited to about 1,000mCi annually and most of that is currently spoken for, thus limiting the ability of this radioisotope pair to enter into research and subsequently clinical trials. The route proposed herein utilizes high energy protons to produce actinium-225 via spallation of a thorium-232 target. As part of previous R and D efforts carried out at Argonne National Laboratory recently in support of the proposed US FRIB facility, it was shown that a very effective production mechanism for actinium-225 is spallation of thorium-232 by high energy proton beams. The base-line simulation for the production rate of actinium-225 by this reaction mechanism is 8E12 atoms per second at 200 MeV proton beam energy with 50 g/cm2 thorium target and 100 kW beam power. An irradiation of one actinium-225 half-life (10 days) produces {approx}100 Ci of actinium-225. For a given beam current the reaction cross section increases slightly with energy to about 400 MeV and then decreases slightly for beam energies in the several GeV regime. The object of this effort is to refine the simulations at proton beam energies of 400 MeV and above up to about 8 GeV. Once completed, the simulations will be experimentally verified using 400 MeV and 8 Ge

  12. Dosimetric characteristics of four PTW microDiamond detectors in high-energy proton beams

    NASA Astrophysics Data System (ADS)

    Marsolat, F.; De Marzi, L.; Patriarca, A.; Nauraye, C.; Moignier, C.; Pomorski, M.; Moignau, F.; Heinrich, S.; Tromson, D.; Mazal, A.

    2016-09-01

    Small diamond detectors are useful for the dosimetry of high-energy proton beams. However, linear energy transfer (LET) dependence has been observed in the literature with such solid state detectors. A novel synthetic diamond detector has recently become commercially available from the manufacturer PTW-Freiburg (PTW microDiamond type 60019). This study was designed to thoroughly characterize four microDiamond detectors in clinical proton beams, in order to investigate their response and their reproducibility in high LET regions. Very good dosimetric characteristics were observed for two of them, with good stability of their response (deviation less than 0.4% after a pre-irradiation dose of approximately 12 Gy), good repeatability (coefficient of variation of 0.06%) and a sensitivity of approximately 0.85 nC Gy‑1. A negligible dose rate dependence was also observed for these two microDiamonds with a deviation of the sensitivity less than 0.7% with respect to the one measured at the reference dose rate of 2.17 Gy min‑1, in the investigated dose rate range from 1.01 Gy min‑1 to 5.52 Gy min‑1. Lateral dose profile measurements showed the high spatial resolution of the microDiamond oriented with its stem perpendicular to the beam axis and with its small sensitive thickness of about 1 μm in the scanning profile direction. Finally, no significant LET dependence was found with these two diamond dosimeters in comparison to a reference ionization chamber (model IBA PPC05). These good results were in accordance to the literature. However, this study showed also a non reproducibility between the devices in terms of stability, sensitivity and LET dependence, since the two other microDiamonds characterized in this work showed different dosimetric characteristics making them not suitable for proton beam dosimetry with a maximum difference of the peak-to-plateau ratio of 6.7% relative to the reference ionization chamber in a clinical 138 MeV proton beam.

  13. Dosimetric characteristics of four PTW microDiamond detectors in high-energy proton beams.

    PubMed

    Marsolat, F; De Marzi, L; Patriarca, A; Nauraye, C; Moignier, C; Pomorski, M; Moignau, F; Heinrich, S; Tromson, D; Mazal, A

    2016-09-01

    Small diamond detectors are useful for the dosimetry of high-energy proton beams. However, linear energy transfer (LET) dependence has been observed in the literature with such solid state detectors. A novel synthetic diamond detector has recently become commercially available from the manufacturer PTW-Freiburg (PTW microDiamond type 60019). This study was designed to thoroughly characterize four microDiamond detectors in clinical proton beams, in order to investigate their response and their reproducibility in high LET regions. Very good dosimetric characteristics were observed for two of them, with good stability of their response (deviation less than 0.4% after a pre-irradiation dose of approximately 12 Gy), good repeatability (coefficient of variation of 0.06%) and a sensitivity of approximately 0.85 nC Gy(-1). A negligible dose rate dependence was also observed for these two microDiamonds with a deviation of the sensitivity less than 0.7% with respect to the one measured at the reference dose rate of 2.17 Gy min(-1), in the investigated dose rate range from 1.01 Gy min(-1) to 5.52 Gy min(-1). Lateral dose profile measurements showed the high spatial resolution of the microDiamond oriented with its stem perpendicular to the beam axis and with its small sensitive thickness of about 1 μm in the scanning profile direction. Finally, no significant LET dependence was found with these two diamond dosimeters in comparison to a reference ionization chamber (model IBA PPC05). These good results were in accordance to the literature. However, this study showed also a non reproducibility between the devices in terms of stability, sensitivity and LET dependence, since the two other microDiamonds characterized in this work showed different dosimetric characteristics making them not suitable for proton beam dosimetry with a maximum difference of the peak-to-plateau ratio of 6.7% relative to the reference ionization chamber in a clinical 138 MeV proton beam. PMID:27499356

  14. Quarkonium production in high energy proton-nucleus collisions: CGC meets NRQCD

    NASA Astrophysics Data System (ADS)

    Kang, Zhong-Bo; Ma, Yan-Qing; Venugopalan, Raju

    2014-01-01

    We study the production of heavy quarkonium states in high energy proton-nucleus collisions. Following earlier work of Blaizot, Fujii, Gelis, and Venugopalan, we systematically include both small x evolution and multiple scattering effects on heavy quark pair production within the Color Glass Condensate (CGC) framework. We obtain for the first time expressions in the Non-Relativistic QCD (NRQCD) factorization formalism for heavy quarkonium differential cross sections as a function of transverse momentum and rapidity. We observe that the production of color singlet heavy quark pairs is sensitive to both "quadrupole" and "dipole" Wilson line correlators, whose energy evolution is described by the Balitsky-JIMWLK equations. In contrast, the color octet channel is sensitive to dipole correlators alone. In a quasi-classical approximation, our results for the color singlet channel reduce to those of Dominguez et al. [1]. We compare our results to those obtained combining the CGC with the color evaporation model and point to qualitative differences in the two approaches.

  15. EGRET High Energy Capability and Multiwavelength Flare Studies and Solar Flare Proton Spectra

    NASA Technical Reports Server (NTRS)

    Chupp, Edward L.

    1997-01-01

    UNH was assigned the responsibility to use their accelerator neutron measurements to verify the TASC response function and to modify the TASC fitting program to include a high energy neutron contribution. Direct accelerator-based measurements by UNH of the energy-dependent efficiencies for detecting neutrons with energies from 36 to 720 MeV in NaI were compared with Monte Carlo TASC calculations. The calculated TASC efficiencies are somewhat lower (by about 20%) than the accelerator results in the energy range 70-300 MeV. The measured energy-loss spectrum for 207 MeV neutron interactions in NaI were compared with the Monte Carlo response for 200 MeV neutrons in the TASC indicating good agreement. Based on this agreement, the simulation was considered to be sufficiently accurate to generate a neutron response library to be used by UNH in modifying the TASC fitting program to include a neutron component in the flare spectrum modeling. TASC energy-loss data on the 1991 June 11 flare was transferred to UNH. Also included appendix: Gamma-rays and neutrons as a probe of flare proton spectra: the solar flare of 11 June 1991.

  16. Detailed parametrization of neutrino and gamma-ray energy spectra from high energy proton-proton interactions

    NASA Astrophysics Data System (ADS)

    Supanitsky, A. D.

    2016-02-01

    Gamma rays and neutrinos are produced as a result of proton-proton interactions that occur in different astrophysical contexts. The detection of these two types of messengers is of great importance for the study of different physical phenomena, related to nonthermal processes, taking place in different astrophysical scenarios. Therefore, the knowledge of the energy spectrum of these two types of particles, as a function of the incident proton energy, is essential for the interpretation of the observational data. In this paper, parametrizations of the energy spectra of gamma rays and neutrinos, originated in proton-proton collisions, are presented. The energy range of the incident protons considered extends from 102 to 108 GeV . The parametrizations are based on Monte Carlo simulations of proton-proton interactions performed with the hadronic interaction models QGSJET-II-04 and EPOS-LHC, which have recently been updated with the data taken by the Large Hadron Collider.

  17. High-efficiency deflection of high energy protons due to channeling along the <110> axis of a bent silicon crystal

    NASA Astrophysics Data System (ADS)

    Scandale, W.; Arduini, G.; Butcher, M.; Cerutti, F.; Garattini, M.; Gilardoni, S.; Lechner, A.; Masi, A.; Mirarchi, D.; Montesano, S.; Redaelli, S.; Rossi, R.; Smirnov, G.; Breton, D.; Burmistrov, L.; Chaumat, V.; Dubos, S.; Maalmi, J.; Puill, V.; Stocchi, A.; Bagli, E.; Bandiera, L.; Germogli, G.; Guidi, V.; Mazzolari, A.; Dabagov, S.; Murtas, F.; Addesa, F.; Cavoto, G.; Iacoangeli, F.; Galluccio, F.; Afonin, A. G.; Chesnokov, Yu. A.; Durum, A. A.; Maisheev, V. A.; Sandomirskiy, Yu. E.; Yanovich, A. A.; Kovalenko, A. D.; Taratin, A. M.; Denisov, A. S.; Gavrikov, Yu. A.; Ivanov, Yu. M.; Lapina, L. P.; Malyarenko, L. G.; Skorobogatov, V. V.; James, T.; Hall, G.; Pesaresi, M.; Raymond, M.

    2016-09-01

    A deflection efficiency of about 61% was observed for 400 GeV/c protons due to channeling, most strongly along the <110> axis of a bent silicon crystal. It is comparable with the deflection efficiency in planar channeling and considerably larger than in the case of the <111> axis. The measured probability of inelastic nuclear interactions of protons in channeling along the <110> axis is only about 10% of its amorphous level whereas in channeling along the (110) planes it is about 25%. High efficiency deflection and small beam losses make this axial orientation of a silicon crystal a useful tool for the beam steering of high energy charged particles.

  18. Using high-energy proton fluence to improve risk prediction for consequences of solar particle events

    NASA Astrophysics Data System (ADS)

    Kim, Myung-Hee Y.; Hayat, Matthew J.; Feiveson, Alan H.; Cucinotta, Francis A.

    2009-12-01

    The potential for exposure to large solar particle events (SPEs) with high energy levels is a major concern during interplanetary transfer and extra-vehicular activities (EVAs) on the lunar and Mars surface. Previously, we have used data from the last 5 solar cycles to estimate percentiles of dose to a typical blood-forming organ (BFO) for a hypothetical astronaut in a nominally shielded spacecraft during a 120-d lunar mission. As part of this process, we made use of complete energy spectra for 34 large historical SPEs to calculate what the BFO mGy-Eq dose would have been in the above lunar scenario for each SPE. From these calculated doses, we then developed a prediction model for BFO dose based solely on an assumed value of integrated fluence above 30 MeV ( Φ30) for an otherwise unspecified future SPE. In this study, we reasoned that since BFO dose is determined more by protons with higher energies than by those with lower energies, more accurate BFO dose prediction models could be developed using integrated fluence above 60 ( Φ60) and above 100 MeV ( Φ100) as predictors instead of Φ30. However to calculate the unconditional probability of a BFO dose exceeding a pre-specified limit ("BFO dose risk"), one must also take into account the distribution of the predictor ( Φ30,Φ60, or Φ100), as estimated from historical SPEs. But Φ60 and Φ100 have more variability, and less available historical information on which to estimate their distributions over many SPE occurrences, than does Φ30. Therefore, when estimating BFO dose risk there is a tradeoff between increased BFO dose prediction at a given energy threshold and decreased accuracy of models for describing the distribution of that threshold over future SPEs as the threshold increases. Even when taking the second of these two factors into account, we still arrived at the conclusion that overall prediction improves as the energy level threshold increases from 30 to 60 to 100 MeV. These results can be applied

  19. Monoenergetic proton backlighter for measuring E and B fields and for radiographing implosions and high-energy density plasmas (invited)

    SciTech Connect

    Li, C. K.; Seguin, F. H.; Frenje, J. A.; Rygg, J. R.; Petrasso, R. D.; Town, R. P. J.; Amendt, P. A.; Hatchett, S. P.; Landen, O. L.; Mackinnon, A. J.; Patel, P. K.; Smalyuk, V. A.; Knauer, J. P.; Sangster, T. C.; Stoeckl, C.

    2006-10-15

    A novel monoenergetic proton backlighter source and matched imaging detector have been utilized on the OMEGA laser system to study electric (E) and magnetic (B) fields generated by laser-plasma interactions and will be utilized in the future to radiograph implosions and high-energy density (HED) plasmas. The backlighter consists of an imploding glass microballoon with D {sup 3}He fuel, producing 14.7 MeV D {sup 3}He protons and 3 MeV DD protons that are then passed through a mesh that divides the protons into beamlets. For quantitative study of E+B field structure, monoenergetic protons have several unique advantages compared to the broad energy spectrum used in previous experiments. Recent experiments have been performed with a single laser beam (intensity of {approx}10{sup 14} W/cm{sup 2}) interacting with a CH foil, and B fields of {approx}0.5 MG and E fields of {approx}1.5x10{sup 8} V/m have been measured using proton deflectometry. LASNEX simulations are being used to interpret these experiments. Additional information will also be presented on the application of this technique to measuring E and B fields associated with Hohlraums and directly driven implosions, to radiographically mapping the areal density ({rho}R) distribution in imploded capsules, and to radiographing HED plasmas.

  20. Remarkable new results for high-energy protons and electrons in the inner Van Allen belt regions

    NASA Astrophysics Data System (ADS)

    Baker, Daniel N.

    2016-04-01

    Early observations indicated that the Earth's Van Allen radiation belts could be separated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. Subsequent studies showed that electrons of moderate energy (less than about one megaelectronvolt) often populate both zones, with a deep 'slot' region largely devoid of particles between them. The two-belt radiation structure was explained as arising from strong electron interactions with plasmaspheric hiss just inside the plasmapause boundary with the inner edge of the outer radiation zone corresponding to the minimum plasmapause location.. Recent Van Allen Probes observations have revealed an unexpected radiation belt morphology, especially at ultrarelativistic kinetic energies (more than several megaelectronvolts). The data show an exceedingly sharp inner boundary for the ultrarelativistic electrons right at L=2.8. Additional, concurrently measured data reveal that this barrier to inward electron radial transport is likely due to scattering by powerful human electromagnetic transmitter (VLF) wave fields. We show that weak, but persistent, wave-particle pitch angle scattering deep inside the Earth's plasmasphere due to manmade signals can act to create an almost impenetrable barrier through which the most energetic Van Allen belt electrons cannot migrate. Inside of this distance, the Van Allen Probes data show that high energy (20 -100 MeV) protons have a double belt structure with a stable peak of flux at L~1.5 and a much more variable belt peaking at L~2.3.

  1. Isochoric heating of matter by laser-accelerated high-energy protons

    NASA Astrophysics Data System (ADS)

    Antici, P.; Fuchs, J.; Atzeni, S.; Benuzzi, A.; Brambrink, E.; Esposito, M.; Koenig, M.; Ravasio, A.; Schreiber, J.; Schiavi, A.; Audebert, P.

    2006-06-01

    We describe an experiment on isochoric heating of matter by intense laser-accelerated protons. The experiment was performed using the LULI 100 TW facility with 15-20 J on target energy and > 1019 W.cm - 2 maximum focused intensity. Focusing the laser on a 10 micron thick Au foil, we accelerated forward a laminar proton beam with a maximum energy of 16 MeV. This proton beam irradiated and heated a secondary target positioned after a variable vacuum gap. The heating was diagnosed by 1D and 2D time-resolved measurements of the optical self-emission of the heated target rear-surface. Detailed results as a function of the Z and the thickness of the secondary target as well as analysis, including a full modelling of the target heating with a 2D hydro-code (DUED) coupled to a proton energy deposition code, were obtained. We have also studied the efficiency of heating as a function of the primary target topology, i.e. either flat, which results in a diverging proton beam, or curved, which has the ability of focusing partly the proton beam.

  2. Rainbow effect in channeling of high energy protons through single-wall carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Petrović, S.; Borka, D.; Nešković, N.

    2005-05-01

    We studied theoretically the angular distributions and the rainbows in the case of 1 GeV protons channeled in the ropes of (10, 10) single-wall carbon nanotubes. It was assumed that the transverse cross section of a rope could be described via a (two-dimensional) hexagonal superlattice with one nanotube per lattice point. The rope length was varied between 2.4 and 7.2 μm, corresponding to the reduced rope lengths associated with the transverse proton motion close to the centers of the regions in between three neighboring nanotubes, Λb, between 0.17 and 0.50, respectively. The angular distributions of channeled protons were generated by the computer simulation method using the numerical solution of the proton equations of motion in the transverse plane. We used the Molière's expression for the interaction potential of the proton and a carbon atom. The rainbow lines were determined numerically too. We showed that they ensured the full explanation of the angular distributions. The effect of zero-degree focusing of channeled ions for the reduced rope length Λb = 0.50 was also observed, indicating the existence of the rainbow cycles in the evolution of the angular distribution. We noted a strong influence of the rainbow effect on the effect of zero-degree focusing.

  3. Baseline measures for net-proton distributions in high energy heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Netrakanti, P. K.; Luo, X. F.; Mishra, D. K.; Mohanty, B.; Mohanty, A.; Xu, N.

    2016-03-01

    We report a systematic comparison of the recently measured cumulants of the net-proton distributions for 0-5% central Au + Au collisions in the first phase of the Beam Energy Scan (BES) Program at the Relativistic Heavy Collider facility to various kinds of possible baseline measures. These baseline measures correspond to an assumption that the proton and anti-proton distributions follow Poisson statistics, Binomial statistics, obtained from a transport model calculation and from a hadron resonance gas model. The higher order cumulant net-proton data for the center of mass energies (√{sNN}) of 19.6 and 27 GeV are observed to deviate from most of the baseline measures studied. The deviations are predominantly due to the difference in shape of the proton distributions between data and those obtained in the baseline measures. We also present a detailed study on the relevance of the independent production approach as a baseline for comparison with the measurements at various beam energies. Our studies point to the need of either more detailed baseline models for the experimental measurements or a description via QCD calculations in order to extract the exact physics process that leads to deviation of the data from the baselines presented.

  4. J/ψ production and suppression in high-energy proton-nucleus collisions

    DOE PAGESBeta

    Ma, Yan -Qing; Venugopalan, Raju; Zhang, Hong -Fei

    2015-10-02

    In this study, we apply a color glass condensate+nonrelativistic QCD (CGC+NRQCD) framework to compute J/ψ production in deuteron-nucleus collisions at RHIC and proton-nucleus collisions at the LHC. Our results match smoothly at high p⊥ to a next-to-leading order perturbative QCD+NRQCD computation. Excellent agreement is obtained for p⊥ spectra at the RHIC and LHC for central and forward rapidities, as well as for the normalized ratio RpA of these results to spectra in proton-proton collisions. In particular, we observe that the RpA data are strongly bounded by our computations of the same for each of the individual NRQCD channels; this resultmore » provides strong evidence that our description is robust against uncertainties in initial conditions and hadronization mechanisms.« less

  5. J/ψ production and suppression in high-energy proton-nucleus collisions

    SciTech Connect

    Ma, Yan -Qing; Venugopalan, Raju; Zhang, Hong -Fei

    2015-10-02

    In this study, we apply a color glass condensate+nonrelativistic QCD (CGC+NRQCD) framework to compute J/ψ production in deuteron-nucleus collisions at RHIC and proton-nucleus collisions at the LHC. Our results match smoothly at high p⊥ to a next-to-leading order perturbative QCD+NRQCD computation. Excellent agreement is obtained for p⊥ spectra at the RHIC and LHC for central and forward rapidities, as well as for the normalized ratio RpA of these results to spectra in proton-proton collisions. In particular, we observe that the RpA data are strongly bounded by our computations of the same for each of the individual NRQCD channels; this result provides strong evidence that our description is robust against uncertainties in initial conditions and hadronization mechanisms.

  6. Water corrosion measurements on tungsten irradiated with high energy protons and spallation neutrons

    NASA Astrophysics Data System (ADS)

    Maloy, Stuart A.; Scott Lillard, R.; Sommer, Walter F.; Butt, Darryl P.; Gac, Frank D.; Willcutt, Gordon J.; Louthan, McIntyre R.

    2012-12-01

    A detailed analysis was performed on the degradation of a tungsten target under water cooling while being exposed to a 761 MeV proton beam at an average current of 0.867 mA to a maximum fluence of 1.3 × 1021 protons/cm2. The target consisted of 3 mm diameter tungsten rods arranged in bundles and cooled with deionized water flowing over their length. Degradation of the tungsten was measured through analyzing water resistivity, tungsten concentration in water samples that were taken during irradiation and through dimensional measurements on the rods after irradiation. Chemical analysis of irradiated water samples showed W concentrations up to 35 μg/ml. Gamma analysis showed increases in concentrations of many isotopes including W-178, Lu-171, Tm-167, Tm-166, Yb-169 and Hf-175. Dimensional measurements performed after irradiation on the W rods revealed a decrease in diameter as a function of position that followed closely the Gaussian proton beam profile along the rod length and indicated a definite beam-effect. A general decrease in diameter, especially on the coolant-water entrance point where turbulent flow was likely, also suggests a chemically and mechanically-driven corrosion effect. A method to estimate the apparent corrosion rate based on proton fluence is presented and application of this method estimates the material loss rate at about 1.9 W atoms/incident proton. From this result, the corrosion rate of tungsten in a 761 MeV, 0.867 mA proton beam was calculated to be 0.073 cm/full power year. of irradiation.

  7. High intensity hadron accelerators

    SciTech Connect

    Teng, L.C.

    1989-05-01

    This rapporteur report consists mainly of two parts. Part I is an abridged review of the status of all High Intensity Hadron Accelerator projects in the world in semi-tabulated form for quick reference and comparison. Part II is a brief discussion of the salient features of the different technologies involved. The discussion is based mainly on my personal experiences and opinions, tempered, I hope, by the discussions I participated in in the various parallel sessions of the workshop. In addition, appended at the end is my evaluation and expression of the merits of high intensity hadron accelerators as research facilities for nuclear and particle physics.

  8. High-energy proton irradiation of C57Bl6 mice under hindlimb unloading

    NASA Astrophysics Data System (ADS)

    Mendonca, Marc; Todd, Paul; Orschell, Christie; Chin-Sinex, Helen; Farr, Jonathan; Klein, Susan; Sokol, Paul

    2012-07-01

    Solar proton events (SPEs) pose substantial risk for crewmembers on deep space missions. It has been shown that low gravity and ionizing radiation both produce transient anemia and immunodeficiencies. We utilized the C57Bl/6 based hindlimb suspension model to investigate the consequences of hindlimb-unloading induced immune suppression on the sensitivity to whole body irradiation with modulated 208 MeV protons. Eight-week old C57Bl/6 female mice were conditioned by hindlimb-unloading. Serial CBC and hematocrit assays by HEMAVET were accumulated for the hindlimb-unloaded mice and parallel control animals subjected to identical conditions without unloading. One week of hindlimb-unloading resulted in a persistent, statistically significant 10% reduction in RBC count and a persistent, statistically significant 35% drop in lymphocyte count. This inhibition is consistent with published observations of low Earth orbit flown mice and with crewmember blood analyses. In our experiments the cell count suppression was sustained for the entire six-week period of observation and persisted for at least 7 days beyond the period of active hindlimb-unloading. C57Bl/6 mice were also irradiated with 208 MeV Spread Out Bragg Peak (SOBP) protons at the Midwest Proton Radiotherapy Institute at the Indiana University Cyclotron Facility. We found that at 8.5 Gy hindlimb-unloaded mice were significantly more radiation sensitive with 35 lethalities out of 51 mice versus 15 out of 45 control (non-suspended) mice within 30 days of receiving 8.5 Gy of SOBP protons (p =0.001). Both control and hindlimb-unloaded stocktickerCBC analyses of 8.5 Gy proton irradiated and control mice by HEMAVET demonstrated severe reductions in WBC counts (Lymphocytes and PMNs) by day 2 post-irradiation, followed a week to ten days later by reductions in platelets, and then reductions in RBCs about 2 weeks post-irradiation. Recovery of all blood components commenced by three weeks post-irradiation. CBC analyses of 8

  9. A high intensity 200 mA proton source for the FRANZ-Project (Frankfurt-Neutron-Source at the Stern-Gerlach-Center)

    SciTech Connect

    Schweizer, W. Ratzinger, U.; Klump, B.; Volk, K.

    2014-02-15

    At the University of Frankfurt a high current proton source has been developed and tested for the FRANZ-Project [U. Ratzinger, L. P. Chau, O. Meusel, A. Schempp, K. Volk, M. Heil, F. Käppeler, and R. Stieglitz, “Intense pulsed neutron source FRANZ in the 1–500 keV range,” ICANS-XVIII Proceedings, Dongguan, April 2007, p. 210]. The ion source is a filament driven arc discharge ion source. The new design consists of a plasma generator, equipped with a filter magnet to produce nearly pure proton beams (92 %), and a compact triode extraction system. The beam current density has been enhanced up to 521 mA/cm{sup 2}. Using an emission opening radius of 4 mm, a proton beam current of 240 mA at 50 keV beam energy in continuous wave mode (cw) has been extracted. This paper will present the current status of the proton source including experimental results of detailed investigations of the beam composition in dependence of different plasma parameters. Both, cw and pulsed mode were studied. Furthermore, the performance of the ion source was studied with deuterium as working gas.

  10. Development and creation of conditions for the radiation of biological objects with high energy protons

    NASA Technical Reports Server (NTRS)

    Popov, V. P.; Portman, A. I.; Sychkov, M. A.; Kolodkin, A. V.; Nikl, I.

    1974-01-01

    Depth distribution of an absorbed proton radiation dose was studied by both calculation and experimental methods on a cylindrical, homogeneous plexiglass phantom that represented the geometric form of a dog. The basis of the heterogeneous phantom was the natural skeleton of a dog, muscle tissue was simulated by a mixture of paraffin and silica filler, and lung tissue by gelatine capsules.

  11. Evaluation of the dosimetric properties of a synthetic single crystal diamond detector in high energy clinical proton beams

    SciTech Connect

    Mandapaka, A. K.; Ghebremedhin, A.; Patyal, B.; Marinelli, Marco; Prestopino, G.; Verona, C.; Verona-Rinati, G.

    2013-12-15

    Purpose: To investigate the dosimetric properties of a synthetic single crystal diamond Schottky diode for accurate relative dose measurements in large and small field high-energy clinical proton beams.Methods: The dosimetric properties of a synthetic single crystal diamond detector were assessed by comparison with a reference Markus parallel plate ionization chamber, an Exradin A16 microionization chamber, and Exradin T1a ion chamber. The diamond detector was operated at zero bias voltage at all times. Comparative dose distribution measurements were performed by means of Fractional depth dose curves and lateral beam profiles in clinical proton beams of energies 155 and 250 MeV for a 14 cm square cerrobend aperture and 126 MeV for 3, 2, and 1 cm diameter circular brass collimators. ICRU Report No. 78 recommended beam parameters were used to compare fractional depth dose curves and beam profiles obtained using the diamond detector and the reference ionization chamber. Warm-up/stability of the detector response and linearity with dose were evaluated in a 250 MeV proton beam and dose rate dependence was evaluated in a 126 MeV proton beam. Stem effect and the azimuthal angle dependence of the diode response were also evaluated.Results: A maximum deviation in diamond detector signal from the average reading of less than 0.5% was found during the warm-up irradiation procedure. The detector response showed a good linear behavior as a function of dose with observed deviations below 0.5% over a dose range from 50 to 500 cGy. The detector response was dose rate independent, with deviations below 0.5% in the investigated dose rates ranging from 85 to 300 cGy/min. Stem effect and azimuthal angle dependence of the diode signal were within 0.5%. Fractional depth dose curves and lateral beam profiles obtained with the diamond detector were in good agreement with those measured using reference dosimeters.Conclusions: The observed dosimetric properties of the synthetic single

  12. Dose equivalent near the bone-soft tissue interface from nuclear fragments produced by high-energy protons.

    PubMed

    Shavers, M R; Poston, J W; Cucinotta, F A; Wilson, J W

    1996-04-01

    During manned space missions, high-energy nucleons of cosmic and solar origin collide with atomic nuclei of the human body and produce a broad linear energy transfer spectrum of secondary particles, called target fragments. These nuclear fragments are often more biologically harmful than the direct ionization of the incident nucleon. That these secondary particles increase tissue absorbed dose in regions adjacent to the bone-soft tissue interface was demonstrated in a previous publication. To assess radiological risks to tissue near the bone-soft tissue interface, a computer transport model for nuclear fragments produced by high energy nucleons was used in this study to calculate integral linear energy transfer spectra and dose equivalents resulting from nuclear collisions of 1-GeV protons transversing bone and red bone marrow. In terms of dose equivalent averaged over trabecular bone marrow, target fragments emitted from interactions in both tissues are predicted to be at least as important as the direct ionization of the primary protons-twice as important, if recently recommended radiation weighting factors and "worst-case" geometry are used. The use of conventional dosimetry (absorbed dose weighted by aa linear energy transfer-dependent quality factor) as an appropriate framework for predicting risk from low fluences of high-linear energy transfer target fragments is discussed. PMID:8617586

  13. Dose equivalent near the bone-soft tissue interface from nuclear fragments produced by high-energy protons

    NASA Technical Reports Server (NTRS)

    Shavers, M. R.; Poston, J. W.; Cucinotta, F. A.; Wilson, J. W.

    1996-01-01

    During manned space missions, high-energy nucleons of cosmic and solar origin collide with atomic nuclei of the human body and produce a broad linear energy transfer spectrum of secondary particles, called target fragments. These nuclear fragments are often more biologically harmful than the direct ionization of the incident nucleon. That these secondary particles increase tissue absorbed dose in regions adjacent to the bone-soft tissue interface was demonstrated in a previous publication. To assess radiological risks to tissue near the bone-soft tissue interface, a computer transport model for nuclear fragments produced by high energy nucleons was used in this study to calculate integral linear energy transfer spectra and dose equivalents resulting from nuclear collisions of 1-GeV protons transversing bone and red bone marrow. In terms of dose equivalent averaged over trabecular bone marrow, target fragments emitted from interactions in both tissues are predicted to be at least as important as the direct ionization of the primary protons-twice as important, if recently recommended radiation weighting factors and "worst-case" geometry are used. The use of conventional dosimetry (absorbed dose weighted by aa linear energy transfer-dependent quality factor) as an appropriate framework for predicting risk from low fluences of high-linear energy transfer target fragments is discussed.

  14. Recent Results on High-Energy Spin Phenomena of Gluons and Sea-Quarks in Polarized Proton-Proton Collisions at Rhic at Bnl

    NASA Astrophysics Data System (ADS)

    Surrow, Bernd

    2014-01-01

    The STAR experiment at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory is carrying out a spin physics program in high-energy polarized proton collisions at √ {s} = 200 GeV and √ {s} = 500 GeV to gain a deeper insight into the spin structure and dynamics of the proton. One of the main objectives of the spin physics program at RHIC is the precise determination of the polarized gluon distribution function. The STAR detector is well suited for the reconstruction of various final states involving jets, π0, π±, e± and γ, which allows to measure several different processes. Recent results suggest a gluon spin contribution to the proton spin at the same level as the quark spin contribution itself. The production of W bosons in polarized p+p collisions at √ {s} = 500 GeV opens a new era in the study of the spin-flavor structure of the proton. W-(+) bosons are produced in \\bar {u} + d (\\bar {d} + u) collisions and can be detected through their leptonic decays, e- + \\bar {ν }e (e++ν e), where only the respective charged lepton is measured. Results of W-(+) production suggest a large asymmetry between the polarization of anti-u and anti-d quarks.

  15. Tungsten fragmentation in nuclear reactions induced by high-energy cosmic-ray protons

    NASA Astrophysics Data System (ADS)

    Chechenin, N. G.; Chuvilskaya, T. V.; Shirokova, A. A.; Kadmenskii, A. G.

    2015-01-01

    Tungsten fragmentation arising in nuclear reactions induced by cosmic-ray protons in space-vehicle electronics is considered. In modern technologies of integrated circuits featuring a three-dimensional layered architecture, tungsten is frequently used as a material for interlayer conducting connections. Within the preequilibrium model, tungsten-fragmentation features, including the cross sections for the elastic and inelastic scattering of protons of energy between 30 and 240 MeV; the yields of isotopes and isobars; their energy, charge, and mass distributions; and recoil energy spectra, are calculated on the basis of the TALYS and EMPIRE-II-19 codes. It is shown that tungsten fragmentation affects substantially forecasts of failures of space-vehicle electronics.

  16. Tungsten fragmentation in nuclear reactions induced by high-energy cosmic-ray protons

    SciTech Connect

    Chechenin, N. G. Chuvilskaya, T. V.; Shirokova, A. A.; Kadmenskii, A. G.

    2015-01-15

    Tungsten fragmentation arising in nuclear reactions induced by cosmic-ray protons in space-vehicle electronics is considered. In modern technologies of integrated circuits featuring a three-dimensional layered architecture, tungsten is frequently used as a material for interlayer conducting connections. Within the preequilibrium model, tungsten-fragmentation features, including the cross sections for the elastic and inelastic scattering of protons of energy between 30 and 240 MeV; the yields of isotopes and isobars; their energy, charge, and mass distributions; and recoil energy spectra, are calculated on the basis of the TALYS and EMPIRE-II-19 codes. It is shown that tungsten fragmentation affects substantially forecasts of failures of space-vehicle electronics.

  17. Characterization of warm dense matter produced by laser-accelerated high-energy protons

    NASA Astrophysics Data System (ADS)

    Nakatsutsumi, M.; Fuchs, J.; Mancic, A.; Robiche, J.; Renaudin, P.; Combis, P.; Dorchies, F.; Harmand, M.; Maynard, G.; Vassaux, J.; Mora, P.; Antici, P.; Fourmaux, S.; Audebert, P.

    2008-11-01

    Producing warm dense plasmas (WDM: solid density, few eV ˜ few 10s eV) is of interest for fundamental plasma physics or ICF. Laser-produced proton heating is of interest since they are short (<1ps) and deposit their energy volumetrically. Experiments were performed using the LULI 100 TW facility to create and characterize WDM. We used, (i) 2D time-resolved optical self-emission of the heated target, (ii) surface expansion velocity measurement through phase measurements of a reflecting probe beam, and (iii) x-ray absorption spectroscopy. We showed that we could produce quasi-uniform heating of solids, as suited for e.g. EoS measurements. Time-resolved solid-liquid-plasma transition has been measured, as well as energy-loss of MeV protons in warm dense plasmas.

  18. Recoil-proton polarization in high-energy deuteron photodisintegration with circularly plarized photons.

    SciTech Connect

    Jiang, X.; Arrington, J.; Benmokhtar, F.; Camsonne, A.; Chen, J. P.; Holt, R. J.; Qattan, I. A.; Reimer, P. E.; Schulte, E. C.; Wijesooriya, K.; Physics; Rutgers Univ.; Univ. Blaise Pascal; Thomas Jefferson National Accelerator Facility

    2007-05-01

    We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.

  19. Recoil-Proton Polarization in High-Energy Deuteron Photodisintegration with Circularly Polarized Photons

    SciTech Connect

    Jiang, X.; Benmokhtar, F.; Glashauser, C.; McCormick, K.; Ransome, R. D.; Arrington, J.; Holt, R. J.; Reimer, P. E.; Schulte, E. C.; Wijesooriya, K.; Camsonne, A.

    2007-05-04

    We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.

  20. Recoil-Proton Polarization in High-Energy Deuteron Photodisintegration with Circularly Polarized Photons

    SciTech Connect

    X. Jiang; J. Arrington; F. Benmokhtar; A. Camsonne; J. P. Chen; S. Choi; E. Chudakov; F. Cusanno; A. Deur; D. Dutta; F. Garibaldi; D. Gaskell; O. Gayou; R. Gilman; C. Glashauser; D. Hamilton; O. Hansen; D. W. Higinbotham; R. J. Holt; C. W. de Jager; M. K. Jones; L. J. Kaufman; E. R. Kinney; K. Kramer; L. Lagamba; R. de Leo; J. Lerose; D. Lhuillier; R. Lindgren; N. Liyanage; K. McCormick; Z.-E. Meziani; R. Michaels; B. Moffit; P. Monaghan; S. Nanda; K. D. Paschke; C. F. Perdrisat; V. Punjabi; I. A. Qattan; R. D. Ransome; P. E. Reimer; B. Reitz; A. Saha; E. C. Schulte; R. Sheyor; K. Slifer; P. Solvignon; V. Sulkosky; G. M. Urciuoli; E. Voutier; K. Wang; K. Wijesooriya; B. Wojtsekhowski; and L. Zhu

    2007-05-01

    We measured the angular dependence of the three recoil-proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily. Transverse polarizations are not well described, but suggest isovector dominance.

  1. Angular dependence of recoil proton polarization in high-energy \\gamma d \\to p n

    SciTech Connect

    X. Jiang; J. Arrington; F. Benmokhtar; A. Camsonne; J.P. Chen; S. Choi; E. Chudakov; F. Cusanno; A. Deur; D. Dutta; F. Garibaldi; D. Gaskell; O. Gayou; R. Gilman; C. Glashauser; D. Hamilton; O. Hansen; D.W. Higinbotham; R.J. Holt; C.W. de Jager; M.K. Jones; L.J. Kaufman; E.R. Kinney; K. Kramer; L. Lagamba; R. de Leo; J. Lerose; D. Lhuillier; R. Lindgren; N. Liyanage; K. McCormick; Z.-E. Meziani; R. Michaels; B. Moffit; P. Monaghan; S. Nanda; K.D. Paschke; C.F. Perdrisat; V. Punjabi; I.A. Qattan; R.D. Ransome; P.E. Reimer; B. Reitz; A. Saha; E.C. Schulte; R. Sheyor; K. Slifer; P. Solvignon; V. Sulkosky; G.M. Urciuoli; E. Voutier; K. Wang; K. Wijesooriya; B. Wojtsekhowski; L. Zhu

    2007-02-26

    We measured the angular dependence of the three recoil proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily.. Transverse polarizations are not well described, but suggest isovector dominance.

  2. Hadron Production in the Restricted Rapidity Intervals in Proton-Nucleus Interactions at High Energies

    NASA Astrophysics Data System (ADS)

    Aggarwal, Madan M.

    Data on 200 and 400 GeV proton interactions with nuclear emulsion have been analyzed. It is found that the multiplicity distributions of the shower particles in the restricted rapidity intervals are well described by the negative binomial distribution (NBD). The dependences of the NBD parameters on rapidity interval, energy and target size have been studied. The results have also been discussed in terms of Giovannini and Van Hove’s clan model of multiparticle production.

  3. The effect of irradiation with high-energy protons on 4H-SiC detectors

    SciTech Connect

    Kazukauskas, V. Jasiulionis, R.; Kalendra, V.; Vaitkus, J.-V.

    2007-03-15

    The effect of irradiation of 4H-SiC ionizing-radiation detectors with various doses (as high as 10{sup 16} cm{sup -2}) of 24-GeV protons is studied. Isotopes of B, Be, Li, He, and H were produced in the nuclear spallation reactions of protons with carbon. Isotopes of Al, Mg, Na, Ne, F, O, and N were produced in the reactions of protons with silicon. The total amount of the produced stable isotopes varied in proportion with the radiation dose from 1.2 x 10{sup 11} to 5.9 x 10{sup 13} cm{sup -2}. It is shown that, at high radiation doses, the contact characteristics of the detectors change appreciably. The potential-barrier height increased from the initial value of 0.7-0.75 eV to 0.85 eV; the rectifying characteristics of the Schottky contacts deteriorated appreciably. These effects are attributed to the formation of a disordered structure of the material as a result of irradiation.

  4. CLUST - EVAP Monte Carlo Simulation Applications for Determining Effective Energy Deposition in Silicon by High Energy Protons

    NASA Technical Reports Server (NTRS)

    ONeill, Pat M.

    2000-01-01

    The CLUST-EVAP is a Monte Carlo simulation of the interaction of high energy (25 - 400 MeV) protons with silicon nuclei. The initial nuclear cascade stage is modeled using the CLUST model developed by Indiana University over 30 years ago. The second stage, in which the excited nucleus evaporates particles in random directions, is modeled according to the evaporation algorithm provided by H. H. K. Tang of IBM. Using the CLUST-EVAP code to model fragment produ6tion and the Vavilov-Landau theory to model fluctuations in direct ionization in thin silicon layers, we have predicted energy deposition in silicon components for various geometrical configurations. We have compared actual measurements with model predictions for geometry's such as single, thin silicon particle detectors, telescopic particle detectors flown in space to measure the environment, and thin sensitive volumes of modern micro-electronic components. We have recently compared the model predictions with actual measurements made by the DOSTEL spectrometer flown in the Shuttle payload bay on STS-84. The model faithfully reproduces the features and aids in interpretation of flight results of this instrument. We have also applied the CLUST-EVAP model to determine energy deposition in the thin sensitive volumes of modern micro-electronic components. We have accessed the ability of high energy (200 MeV) protons to induce latch-up in certain devices that are known to latch up in heavy ion environments. However, some devices are not nearly as susceptible to proton induced latch-up as expected according to their measured heavy ion latch-up cross sections. The discrepancy is believed to be caused by the limited range of the proton-silicon interaction fragments. The CLUST-EV AP model was used to determine a distribution of these fragments and their range and this is compared to knowledge of the ranges required based on the known device structure. This information is especially useful in accessing the risk to on

  5. High energy proton radiation damage to (AlGa)As-G aAs solar cells

    NASA Technical Reports Server (NTRS)

    Loo, R.; Goldhammer, L.; Kamath, S.; Knechtli, R. C.

    1979-01-01

    Twelve 2 + 2 sq cm (AlGa)As-GaAs solar cells were fabricated and were subjected to 15.4 and 40 MeV of proton irradiation. The results showed that the GaAs cells degrade considerably less than do conventional and developmental K7 silicon cells. The detailed characteristics of the GaAs and silicon cells, both before and after irradiation, are described. Further optimization of the GaAs cells seems feasible, and areas for future work are suggested.

  6. Laser-Foil Acceleration of High-Energy Protons in Small-Scale Plasma Gradients

    SciTech Connect

    Fuchs, J.; Audebert, P.; Cecchetti, C. A.; Borghesi, M.; Romagnani, L.; Grismayer, T.; Mora, P.; D'Humieres, E.; Sentoku, Y.; Antici, P.; Atzeni, S.; Schiavi, A.; Pipahl, A.; Toncian, T.; Willi, O.

    2007-07-06

    Proton beams laser accelerated from thin foils are studied for various plasma gradients on the foil rear surface. The beam maximum energy and spectral slope reduce with the gradient scale length, in good agreement with numerical simulations. The results also show that the jxB mechanism determines the temperature of the electrons driving the ion expansion. Future ion-driven fast ignition of fusion targets will use multikilojoule petawatt laser pulses, the leading part of which will induce target preheat. Estimates based on the data show that this modifies by less than 10% the ion beam parameters.

  7. Laser-foil acceleration of high-energy protons in small-scale plasma gradients.

    PubMed

    Fuchs, J; Cecchetti, C A; Borghesi, M; Grismayer, T; d'Humières, E; Antici, P; Atzeni, S; Mora, P; Pipahl, A; Romagnani, L; Schiavi, A; Sentoku, Y; Toncian, T; Audebert, P; Willi, O

    2007-07-01

    Proton beams laser accelerated from thin foils are studied for various plasma gradients on the foil rear surface. The beam maximum energy and spectral slope reduce with the gradient scale length, in good agreement with numerical simulations. The results also show that the jxB mechanism determines the temperature of the electrons driving the ion expansion. Future ion-driven fast ignition of fusion targets will use multikilojoule petawatt laser pulses, the leading part of which will induce target preheat. Estimates based on the data show that this modifies by less than 10% the ion beam parameters. PMID:17678159

  8. Comparative study by IBIC of Si and SiC diodes irradiated with high energy protons

    NASA Astrophysics Data System (ADS)

    Garcia Lopez, J.; Jimenez-Ramos, M. C.; Rodriguez-Ramos, M.; Ceballos, J.; Linez, F.; Raisanen, J.

    2016-04-01

    The transport properties of a series of Si and SiC diodes have been studied using the Ion Beam Induced Charge (IBIC) technique. Structural defects were induced into the samples during the irradiation with 17 MeV protons. The experimental values of the charge collection efficiency (CCE) vs bias voltages have been analyzed using a modified drift-diffusion model, which takes into account the recombination of carriers in the neutral and depletion regions. From these simulations, we have obtained the values of the carrier's lifetime for pristine and irradiated diodes, which are found to degrade faster in the case of the SiC samples. However, the decrease of the CCE at high bias voltages is more important for the Si detectors, indicative of the lower radiation hardness of this material compared to SiC. The nature of the proton-induced defects on Si wafers has been studied by Positron Annihilation Spectroscopy (PAS) and Doppler Broadening Spectroscopy (DBS). The results suggest that the main defect detected by the positrons in p-type samples is the divacancy while for n-type at least a fraction of the positron annihilate in another defect. The concentration of defects is much lower than the number of vacancies predicted by SRIM.

  9. Resistivity changes in superconducting-cavity-grade Nb following high-energy proton irradiation

    SciTech Connect

    Snead, C.L. Jr.; Hanson, A.; Greene, G.A.

    1997-12-01

    Niobium superconducting rf cavities are proposed for use in the proton LINAC accelerators for spallation-neutron applications. Because of accidental beam loss and continual halo losses along the accelerator path, concern for the degradation of the superconducting properties of the cavities with accumulating damage arises. Residual-resistivity-ratio (RRR) specimens of Nb, with a range of initial RRR`s were irradiated at room temperature with protons at energies from 200 to 2000 MeV. Four-probe resistance measurements were made at room temperature and at 4.2 K both prior to and after irradiation. Nonlinear increases in resistivity simulate expected behavior in cavity material after extended irradiation, followed by periodic anneals to room temperature: For RRR = 316 material, irradiations to (2 - 3) x 10{sup 15} p/cm{sup 2} produce degradations up to the 10% level, a change that is deemed operationally acceptable. Without. periodic warming to room temperature, the accumulated damage energy would be up to a factor of ten greater, resulting in unacceptable degradations. Likewise, should higher-RRR material be used, for the same damage energy imparted, relatively larger percentage changes in the RRR will result.

  10. Production of ACTINIUM-225 via High Energy Proton Induced Spallation of THORIUM-232

    NASA Astrophysics Data System (ADS)

    Harvey, James; Nolen, Jerry A.; Kroc, Thomas; Gomes, Itacil; Horwitz, E. Philip.; McAlister, Daniel R.

    2010-06-01

    The science of cancer research is currently expanding its use of alpha particle emitting radioisotopes. Coupled with the discovery and proliferation of molecular species that seek out and attach to tumors, new therapy and diagnostics are being developed to enhance the treatment of cancer and other diseases. This latest technology is commonly referred to as Alpha Immunotherapy (AIT). Actinium-225/Bismuth-213 is a parent/daughter alpha-emitting radioisotope pair that is highly sought after because of the potential for treating numerous diseases and its ability to be chemically compatible with many known and widely used carrier molecules (such as monoclonal antibodies and proteins/peptides). The object of this effort is to refine the simulations for producing actinium-225 at proton beam energies of 400 MeV and above up to about 8 GeV. Once completed, the simulations will be experimentally verified using 400 MeV and 8 GeV protons available at Fermi National Accelerator Laboratory. Targets will be processed at Argonne National Laboratory to separate and purify the actinium-225 that will subsequently be transferred to NorthStar laboratory facilities for product quality testing and comparison to the product quality of ORNL produced actinium-225, which is currently the industry standard. The test irradiations at FNAL will produce 1-20 mCi per day which is more than sufficient for quantitative evaluation of the proposed production process.

  11. Effects of high energy protons on the E771 silicon microstrip detector

    NASA Astrophysics Data System (ADS)

    Alexopoulos, T.; Antoniazzi, L.; Arenton, M.; Ballagh, C.; Bingham, H.; Blankman, A.; Block, M.; Boden, A.; Borodin, S.; Budagov, J.; Cao, Z. L.; Cataldi, G.; Chen, T. Y.; Clark, K.; Cline, D.; Conetti, S.; Cooper, M.; Corti, G.; Cox, B.; Creti, P.; Dukes, E.; Durandet, C.; Elia, V.; Erwin, A.; Fortney, L.; Golovatyuk, S.; Gorini, E.; Grancagnolo, F.; Haire, M.; Hanlet, P.; He, M.; Introzzi, G.; Jenkins, M.; Jennings, J.; Judd, D.; Kaeding, T.; Kononenko, W.; Kowald, W.; lanza, A.; Lau, K.; Liguori, G.; Lys, J.; Mazur, P.; McManus, A.; Misawa, S.; Mo, G.; Murphy, T.; Nelson, K.; Newcomer, M.; Panareo, M.; Ramachandran, S.; Recagni, M.; Rhoades, J.; Segal, J.; Selove, W.; Smith, R.; Spiegel, L.; Sun, J.; Tokar, S.; Torre, P.; Trischuk, J.; Trojak, T.; Tsyganov, E.; Turnbull, L.; VanBerg, R.; Wagoner, D.; Wang, C.; Wang, H. C.; Wei, C.; Yang, W.; Yao, N.; Zhang, N.; Zhang, S. N.; Zou, B.

    1993-01-01

    A silicon strip detector (SSD) system for use in very high rate experiments has been operated in Experiment E771 (Cox, 1989) at the Fermi National Accelerator laboratory. The detector electronics were designed (Swoboda, 1990; Bowden, 1990; Zimmerman, 1989; Christian, 1991) to meet the specific needs of Fermilab experiment E771 using ASIC chip sets where commercial circuits were not suitable. The electronics for the SSD were designed to operate at rates up to 60 Mhz and were operated at interaction rates up to 10 7 interaction/sec (beam rates of 2 × 10 8 proton/sec). In addition to being very fast, the detector for the 1991 run was very compact with 10000 channels of active detector in a volume fo 5cm × 5cm × 10cm. An expansion of the system to 16000 channels is planned for the next Fermilab fixed target run. The strip pitch ranged from 25 μ m in the center of the detector near the target to 100 μ m pitch at the most downstream, outer edges of the detector. The readout is a latch design with pipelined readout and appears to have single strip efficiencies of ≈ 75% even in the presence of a high radiation dose (∽ 10 14 protons/cm 2) and high leakage currents(≈ 1 nA/strip). The detector and associated amplifier electronics has presently been operated at 17° C and is designed to operate as low as 8° C.

  12. The influence of the Earth's magnetosphere on the high-energy solar protons

    NASA Technical Reports Server (NTRS)

    Bazilevskaya, G. A.; Makhmutov, V. S.; Charakhchyan, T. N.

    1985-01-01

    In the Earth's polar regions the intensity of the solar protons with the energy above the critical energy of geomagnetic cutoff is the same as in the interplanetary space. The penumbra in the polar regions is small and the East-West effect is also small. However the geomagnetic cutoff rigidity R sub c in polar regions is difficult to calculate because it is not sufficient to include only the internal sources of the geomagnetic field. During the magneto-quiescent periods the real value of R sub c can be less by 0.1 GV than the calculated value because of the external sources. During the geomagnetic storms the real value of R sub c is still lower.

  13. Pyrolysis of complex organics following high-energy proton irradiation of a simple inorganic gas mixture

    NASA Astrophysics Data System (ADS)

    Takano, Yoshinori; Marumo, Katsumi; Yabashi, Suguru; Kaneko, Takeo; Kobayashi, Kensei

    2004-08-01

    Complex organics formed by 3MeV proton irradiation of a simple inorganic gas mixture with a composition representative of the primitive earth atmosphere (carbon monoxide, nitrogen, and water) were characterized by application of Curie-point pyrolysis. Pyrolysis products consisted of a wide variety of organic compounds including amide compounds, heterocyclic, and polycyclic aromatic hydrocarbons. The present data showed that primary and primitive organic matter serving as "precursors" to fundamental building blocks associated with life might have been formed in a gaseous mixture of a similar composition to that of the primitive earth atmosphere. Large numbers of endogenous organic compounds and protocatalysis components produced by cosmic rays may have contributed significantly to the early stages of chemical evolution on the primitive earth.

  14. Studies and calculations of transverse emittance growth in high-energy proton storage rings

    SciTech Connect

    Mane, S.R.; Jackson, G.

    1989-03-01

    In the operation of proton-antiproton colliders, an important goal is to maximize the integrated luminosity. During such operations in the Fermilab Tevatron, the transverse beam emittances were observed to grow unexpectedly quickly, thus causing a serious reduction of the luminosity. We have studied this phenomenon experimentally and theoretically. A formula for the emittance growth rate, due to random dipole kicks, is derived. In the experiment, RF phase noise of known amplitude was deliberately injected into the Tevatron to kick the beam randomly, via dispersion at the RF cavities. Theory and experiment are found to agree reasonably well. We also briefly discuss the problem of quadrupole kicks. 14 refs., 2 figs., 3 tabs.

  15. Assessing Antibody Microarray for Space Missions: Effect of Long-term Storage, Gamma radiation and High Energy proton radiation

    NASA Astrophysics Data System (ADS)

    de Diego-Castilla, G.; Parro, V.

    2012-09-01

    Fluorescent antibody microarray has been proposed for Molecular biomarker detector in planetary exploration [1]. A number of different environmental stresses may affect the antibody performance, such as temperatures variations, highly penetrating radiation and high energy particles. Here we have tested the effect of gamma radiation, proton radiation and longterm storage on the microarray immunoassay and fluorocromes. Although different antibodies might have different susceptibilities we conclude that there was not significant reduction in the functionality of antibodies printed on the microarray and the fluorescent tracers antibodies, even in a extreme case of receiving a radiation dose 3000-fold than a biochip would receive in a trip mission to Mars. In summary, antibodies are suitable for use in planetary exploration purposes.

  16. Monte Carlo simulation and parameterized treatment on the effect of nuclear elastic scattering in high-energy proton radiography

    NASA Astrophysics Data System (ADS)

    Xu, Hai-Bo; Zheng, Na

    2015-07-01

    A version of Geant4 has been developed to treat high-energy proton radiography. This article presents the results of calculations simulating the effects of nuclear elastic scattering for various test step wedges. Comparisons with experimental data are also presented. The traditional expressions of the transmission should be correct if the angle distribution of the scattering is Gaussian multiple Coulomb scattering. The mean free path (which depends on the collimator angle) and the radiation length are treated as empirical parameters, according to transmission as a function of thickness obtained by simulations. The results can be used in density reconstruction, which depends on the transmission expressions. Supported by NSAF (11176001) and Science and Technology Developing Foundation of China Academy of Engineering Physics (2012A0202006)

  17. [Indralin--a novel effective radioprotector during irradiation by high-energy protons].

    PubMed

    Shashkov, V S; Efimov, V I; Vasin, M V; Antipov, V V; Iliukhin, A V; Vlasov, P A; Karsanova, S K; Grigor'ev, Iu G; Ushakov, I B

    2010-01-01

    Experiments with 120 mongrel dogs were aimed at the assessment of radio protective strength of indralin and local shielding of the pelvic marrow from 2.5 Gy, and also their concurrent use for the dogs irradiated by protons (240 MeV) at absolutely lethal and over-lethal 4 Gy and 5 Gy. Clinical observations, hematological investigations and ECG analysis of survived animals were conducted 4.5 years post the irradiation. Dogs that remained healthy following 3.5 to 4.5 years since the irradiation were sacrificed for pathomorphological investigations. The radioprotective effect of local shielding against 4 Gy was weak while this effect of intramuscular indralin (10, 20, 40 mg/kg of body) was significant reaching 50 to 67.7%. The concurrent use of two methods had, apparently, potentiated the 100% radioprotection of the animals irradiated by overlethal 5 Gy. Blood investigations of the survived dogs every 2-4 months evidenced that complete recovery of the total leukocyte count had taken 9 to 13 months. Also, dogs' pregnancy in 9-10 months since the beginning of irradiation pointed to maintenance of fertility and the ability to parturiate 2 or 3 times yielding 5-6 live cubs. Necropsy of the dogs did not reveal gross macroscopic structural changes of visceral organs or tissues. Seven out of 27 sacrificed dogs had benign tumors infrequent in intact dogs at this age. PMID:20803992

  18. On the nucleon effective mass role to the high energy proton spallation reactions

    NASA Astrophysics Data System (ADS)

    Santos, B. M.; Pinheiro, A. R. C.; Gonçalves, M.; Duarte, S. B.; Cabral, R. G.

    2016-04-01

    We explore the effect of the nucleon effective mass to the dynamic evolution of the rapid phase of proton-nucleus spallation reactions. The analysis of the relaxation time for the non-equilibrium phase is studied by variations in the effective mass parameter. We determine the final excitation energy of the hot residual nucleus at the end of cascade phase and the de-excitation of the nuclear system is carried out considering the competition of particle evaporation and fission processes. It was shown that the excitation energy depends of the hot compound residual nucleus at the end of the rapid phase on the changing effective mass. The multiplicity of particles was also analyzed in cascade and evaporation phase of the reaction. The use of nucleon effective mass during cascade phase can be considered as an effect of the many-body nuclear interactions not included explicitly in a treatment to the nucleon-nucleon interaction inside the nucleus. This procedure represents a more realistic scenario to obtain the neutron multiplicity generated in this reaction, which is a benchmark for the calculation of the neutronic in the ADS reactors.

  19. High energy density proton exchange membrane fuel cell with dry reactant gases

    SciTech Connect

    Srinivasan, S.; Gamburzev, S.; Velev, O.A.

    1996-12-31

    Proton exchange membrane fuel cells (PEMFC) require careful control of humidity levels in the cell stack to achieve a high and stable level of performance. External humidification of the reactant gases, as in the state-of-the-art PEMFCs, increases the complexity, the weight, and the volume of the fuel cell power plant. A method for the operation of PEMFCs without external humidification (i.e., self-humidified PEMFCs) was first developed and tested by Dhar at BCS Technology. A project is underway in our Center to develop a PEMFC cell stack, which can work without external humidification and attain a performance level of a current density of 0.7 A/cm{sup 2} at a cell potential of 0.7 V, with hydrogen/air as reactants at 1 atm pressure. In this paper, the results of our efforts to design and develop a PEMFC stack requiring no external humidification will be presented. This paper focuses on determining the effects of type of electrodes, the methods of their preparation, as well as that of the membrane and electrode assembly (MEA), platinum loading and types of electrocatalyst on the performance of the PEMFC will be illustrated.

  20. High energy efficiency and high power density proton exchange membrane fuel cells: Electrode kinetics and mass transport

    NASA Technical Reports Server (NTRS)

    Srinivasan, Supramaniam; Velev, Omourtag A.; Parthasathy, Arvind; Manko, David J.; Appleby, A. John

    1991-01-01

    The development of proton exchange membrane (PEM) fuel cell power plants with high energy efficiencies and high power densities is gaining momentum because of the vital need of such high levels of performance for extraterrestrial (space, underwater) and terrestrial (power source for electric vehicles) applications. Since 1987, considerable progress has been made in achieving energy efficiencies of about 60 percent at a current density of 200 mA/sq cm and high power densities (greater than 1 W/sq cm) in PEM fuel cells with high (4 mg/sq cm) or low (0.4 mg/sq cm) platinum loadings in electrodes. The following areas are discussed: (1) methods to obtain these high levels of performance with low Pt loading electrodes - by proton conductor impregnation into electrodes, localization of Pt near front surface; (2) a novel microelectrode technique which yields electrode kinetic parameters for oxygen reduction and mass transport parameters; (3) demonstration of lack of water transport from anode to cathode; (4) modeling analysis of PEM fuel cell for comparison with experimental results and predicting further improvements in performance; and (5) recommendations of needed research and development for achieving the above goals.

  1. Contributions from Ultraviolet Spectroscopy to the Prediction of High-energy Proton Hazards from CME Shocks

    NASA Astrophysics Data System (ADS)

    Lin, J.; Raymond, J. C.; Cranmer, S. R.; Kohl, J. L.

    2004-05-01

    A significant potential hazard to astronauts and their equipment in interplanetary space is the relativistic proton flux produced by coronal mass ejections (CMEs) and solar flares. The longest-duration phase of solar energetic particle (SEP) activity is believed to come from the CME shock as it propagates through the extended corona and heliosphere. Ultraviolet spectroscopy by SOHO has revealed a means for: (1) detecting and characterizing CME shocks in the corona, and (2) determining the plasma conditions in the pre-CME corona which are needed to understand the formation and evolution of shocks. Such remote sensing - combined with models of SEP acceleration and transport - can be used to predict the strength, duration, and production sites of the radiation. This poster describes the specific means by which ultraviolet spectroscopy and other remote-sensing data can be used to determine the inputs and boundary conditions for individual events (such as the October-November 2003 storms) in existing SEP model codes. We also discuss an additional potential source of SEP radiation associated with electric fields in the current sheets that form in flare regions in the wake of CME. Both observations and model calculations show that the reconnection-induced electric field can reach a maximum strength of a few V/cm within tens of minutes after the onset of the eruption, then decreases gradually over several hours. SEPs produced in these regions may account for X-rays and γ -rays observed prior to the formation of CME shocks. Ultraviolet spectroscopy has been shown to provide constraints on the plasma properties in all of the above CME features. This work is supported by NASA under grant NAG5-12865 to the Smithsonian Astrophysical Observatory, by Agenzia Spaziale Italiana, and by the Swiss contribution to ESA's PRODEX program.

  2. The NASA High Intensity Radiated Fields Laboratory

    NASA Technical Reports Server (NTRS)

    Williams, Reuben A.

    1997-01-01

    High Intensity Radiated Fields (HIRF) are the result of a multitude of intentional and nonintentional electromagnetic sources that currently exists in the world. Many of today's digital systems are susceptible to electronic upset if subjected to certain electromagnetic environments (EME). Modern aerospace designers and manufacturers increasingly rely on sophisticated digital electronic systems to provide critical flight control in both military, commercial, and general aviation aircraft. In an effort to understand and emulate the undesired environment that high energy RF provides modern electronics, the Electromagnetics Research Branch (ERB) of the Flight Electronics and Technology Division (FETD) conducts research on RF and microwave measurement methods related to the understanding of HIRF. In the High Intensity Radiated Fields Laboratory, the effects of high energy radiating electromagnetic fields on avionics and electronic systems are tested and studied.

  3. High intensity SRF proton linac workshop (vugraphs)

    SciTech Connect

    Rusnak, B.A.

    1995-11-01

    The meeting is divided into four sections. The first section is the general introduction and included opening remarks and an overview of APT (accelerator product of tritium). The second section contains vugraphs from the cavity-structures working group. The third section is comprised of vugraphs from the couplers and rf working group. And the fourth section contains vugraphs of the system integration group.

  4. High energy neutron radiography

    SciTech Connect

    Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

    1996-06-01

    High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos.

  5. Rapid Cycling Synchrotrons and Accumulator Rings for High-Intensity Hadron Beams

    NASA Astrophysics Data System (ADS)

    Tang, Jingyu

    2014-02-01

    Boosted by the needs in high-energy physics and nuclear physics and also multidisciplinary applications, high-intensity proton synchrotrons and accumulator rings have been developed quickly around the world over the last 30 years. New projects and plans are proposed with even higher beam power. The proton beam power has increased from less than 10 kW in the 1970s to about 1 MW level today, and the required beam power in the coming decade is a few MW. This article reviews the achievements in designing and constructing rapid cycling synchrotrons (RCSs) and accumulator rings (ARs) and the future development trends, principally on proton beams but also including heavy ion beams. It presents the evolution of RCS and AR machines, today's design philosophy, relevant accelerator physics, and also state-of-the-art accelerator technology.

  6. Production of high energy and low flux protons using 2D(3He,p)4He for space detector calibrations

    NASA Astrophysics Data System (ADS)

    Wang, Y. Q.; Burward-Hoy, J. M.; Tesmer, J. R.

    2014-08-01

    In this report, we want to demonstrate that besides the conventional use for elemental analysis and depth profiling by ion beam analysis (IBA), particles generated through ion-solid interactions in IBA may find other novel and important applications. Specifically, we use Rutherford backscattered and nuclear reaction produced high energy proton particles to calibrate an energetic particle subsystem (called ZEP) of the Space and Atmospheric Burst Reporting System (SABRS) at Los Alamos National Laboratory (LANL). To simulate low radiation flux in the space, we have devised an experiment that uses an ultrathin (∼51.8 nm) self-support gold foil to scatter a proton beam from a 3 MV Tandem accelerator into the ZEP subsystem. Direct backscattering from the thin gold foil produces proton particles with tunable energies of 0.2-6.0 MeV and desired counting rates of <10 kHz. To extend the proton particle energy beyond the Tandem's limit of 6 MeV, a high Q-value nuclear reaction, 2D + 3He → p + 4He + 18.352 MeV, was used. This reaction allows us to obtain as high as 25.6 MeV proton particles on our 3 MV tandem accelerator, more than 4 times as high as the accelerator's maximum proton beam energy, and has greatly extended our proton energy range for this calibration activity. Preliminary ZEP subsystem calibration results are presented.

  7. Do you want to build such a machine? : Designing a high energy proton accelerator for Argonne National Laboratory.

    SciTech Connect

    Paris, E.

    2004-04-05

    Argonne National Laboratory's efforts toward researching, proposing and then building a high-energy proton accelerator have been discussed in a handful of studies. In the main, these have concentrated on the intense maneuvering amongst politicians, universities, government agencies, outside corporations, and laboratory officials to obtain (or block) approval and/or funds or to establish who would have control over budgets and research programs. These ''top-down'' studies are very important but they can also serve to divorce such proceedings from the individuals actually involved in the ground-level research which physically served to create theories, designs, machines, and experiments. This can lead to a skewed picture, on the one hand, of a lack of effect that so-called scientific and technological factors exert and, on the other hand, of the apparent separation of the so-called social or political from the concrete practice of doing physics. An exception to this approach can be found in the proceedings of a conference on ''History of the ZGS'' held at Argonne at the time of the Zero Gradient Synchrotron's decommissioning in 1979. These accounts insert the individuals quite literally as they are, for the most part, personal reminiscences of those who took part in these efforts on the ground level. As such, they are invaluable raw material for historical inquiry but generally lack the rigor and perspective expected in a finished historical work. The session on ''Constructing Cold War Physics'' at the 2002 annual History of Science Society Meeting served to highlight new approaches circulating towards history of science and technology in the post-WWII period, especially in the 1950s. There is new attention towards the effects of training large numbers of scientists and engineers as well as the caution not to equate ''national security'' with military preparedness, but rather more broadly--at certain points--with the explicit ''struggle for the hearts and minds of

  8. On the retention of high-energy protons and nuclei with charges Z or equal to 2 in large solar flares after the process of their acceleration

    NASA Technical Reports Server (NTRS)

    Volodichev, N. N.; Kuzhevsky, B. M.; Nechaev, O. Y.; Savenko, I. A.

    1985-01-01

    Data which suggest that the protons with energies of up to several GeV should be retained on the Sun after the process of their acceleration are presented. The protons are on the average retained for 15 min, irrespectively of the solar flare heliolatitude and of the accelerated particle energy ranging from 100 MeV to several GeV. It is suggested that the particles are retained in a magnetic trap formed in a solar active region. No Z or = 2 nuclei of solar origin during large solar flares. The absence of the 500 MeV/nucleon nuclei with Z or = 2 may be due to their retention in the magnetic trap which also retains the high-energy protons. During the trapping time the approx. 500 MeV/nucleon nuclei with Z or = 2 may escape due to nuclear interactions and ionization loss.

  9. Comparative Studies of Hard X-Ray Spectral Evolution in Solar Flares with High-Energy Proton Events Observed at Earth

    NASA Astrophysics Data System (ADS)

    Kiplinger, Alan L.

    1995-11-01

    This paper presents the results of two extensive studies of hard X-ray spectral evolution in solar flares and their associations with energetic interplanetary proton events. The focus of this work is to establish the degree to which events that display progressively hardening hard X-ray spectra, at any time and over all observable timescales, are associated with high-energy interplanetary proton events. The first study examined a sample of 152 hard X-ray flares well observed with the HXRBS instrument on the Solar Maximum Mission (SMM). The study showed that 22 events revealed a progressive spectral hardening either over flux peaks (i.e., a soft-hard- harder spectral evolution) or during flux decays and that 18 of these 22 events (82%) had associated 10 MeV proton events or enhancements. Conversely, the absence of spectral hardening is associated with the absence of interplanetary protons with 124 of the 130 remaining flares (95.4%). Since the hard X-ray counting rate threshold of the first study was sufficiently high (5000 counts s-1) to exclude many flares (more than 36%) associated with the largest interplanetary proton events, a second study was conducted using 193 less intense HXRBS events (a one out of three sample) and their associations with only large proton events. This study also identifies events with progressive spectral hardening. It also employs selection criteria suggested by the results of the first study to "predict" which flares would or would not have associated large proton events. This prescription for "predicting" proton events did so correctly for four large (SESC qualified) proton events, missed none, and produced only one "false alarm" in which the criteria were met but only a small proton event was seen at earth. Thus, a correct "prediction" was made for all but one of the 193 events. The results of the first study are then combined with the weighted results of the one out of three study, using the same selection criteria, to project

  10. Induction of Cell Death through Alteration of Oxidants and Antioxidants in Epithelial Cells Exposed to High Energy Protons

    NASA Technical Reports Server (NTRS)

    Ramesh, Govindarajan; Wu, Honglu

    2012-01-01

    Radiation affects several cellular and molecular processes including double strand breakage, modifications of sugar moieties and bases. In outer space, protons are the primary radiation source which poses a range of potential health risks to astronauts. On the other hand, the use of proton radiation for tumor radiation therapy is increasing as it largely spares healthy tissues while killing tumor tissues. Although radiation related research has been conducted extensively, the molecular toxicology and cellular mechanisms affected by proton radiation remain poorly understood. Therefore, in the present study, we irradiated rat epithelial cells (LE) with different doses of protons and investigated their effects on cell proliferation and cell death. Our data showed an inhibition of cell proliferation in proton irradiated cells with a significant dose dependent activation and repression of reactive oxygen species (ROS) and antioxidants, glutathione and superoxide dismutase respectively as compared to control cells. In addition, apoptotic related genes such as caspase-3 and -8 activities were induced in a dose dependent manner with corresponding increased levels of DNA fragmentation in proton irradiated cells than control cells. Together, our results show that proton radiation alters oxidant and antioxidant levels in the cells to activate apoptotic pathway for cell death.

  11. Induction of Cell Death Through Alteration of Oxidants and Antioxidants in Epithelial Cells Exposed to High Energy Protons

    NASA Astrophysics Data System (ADS)

    Ramesh, Govindarajan; Wu, Honglu

    2012-07-01

    Radiation affects several cellular and molecular processes including double strand breakage, modifications of sugar moieties and bases. In outer space, protons are the primary radiation source which poses a range of potential health risks to astronauts. On the other hand, the use of proton radiation for tumor radiation therapy is increasing as it largely spares healthy tissues while killing tumor tissues. Although radiation related research has been conducted extensively, the molecular toxicology and cellular mechanisms affected by proton radiation remain poorly understood. Therefore, in the present study, we irradiated rat epithelial cells (LE) with different doses of protons and investigated their effects on cell proliferation and cell death. Our data showed an inhibition of cell proliferation in proton irradiated cells with a significant dose dependent activation and repression of reactive oxygen species (ROS) and antioxidants, glutathione and superoxide dismutase respectively as compared to control cells. In addition, apoptotic related genes such as caspase-3 and -8 activities were induced in a dose dependent manner with corresponding increased levels of DNA fragmentation in proton irradiated cells than control cells. Together, our results show that proton radiation alters oxidant and antioxidant levels in the cells to activate apoptotic pathway for cell death.

  12. High-energy Coulomb breakup of proton-dripline nuclei as a tool to study radiative-capture reactions of astrophysical interest

    NASA Astrophysics Data System (ADS)

    Sümmerer, K.

    2007-11-01

    High-energy Coulomb dissociation (CD) can be used to investigate the time-reversed process, radiative capture, for unstable nuclei where the direct capture reaction is difficult or impossible to perform. At GSI, we have run a series of CD measurements involving the proton-halo nucleus 8B which plays a major role in solar-neutrino physics. We could show that for this case CD and direct proton capture yield the same result. Theoretical guidance is necessary, however, to make sure that contributions of different electro-magnetic multipolarities and nuclear dissociation processes are well under control. Recently, we have complemented the LAND/ALADIN experimental apparatus at GSI with new Si microstrip detectors and proton-drift-chambers to continue similar studies with radioactive beams from the fragment separator FRS at GSI. The first case of astrophysical interest to be studied will be the CD of 27P. Another case will be the 2-proton breakup of 17Ne to investigate radiative two-proton capture on 15O, a process which could modify the reaction flow of the rp-process.

  13. High energy conversion efficiency in laser-proton acceleration by controlling laser-energy deposition onto thin foil targets

    SciTech Connect

    Brenner, C. M.; Robinson, A. P. L.; Markey, K.; Scott, R. H. H.; Lancaster, K. L.; Musgrave, I. O.; Spindloe, C.; Winstone, T.; Wyatt, D.; Neely, D.; Gray, R. J.; McKenna, P.; Rosinski, M.; Badziak, J.; Wolowski, J.; Deppert, O.; Batani, D.; Davies, J. R.; Hassan, S. M.; Tatarakis, M.; and others

    2014-02-24

    An all-optical approach to laser-proton acceleration enhancement is investigated using the simplest of target designs to demonstrate application-relevant levels of energy conversion efficiency between laser and protons. Controlled deposition of laser energy, in the form of a double-pulse temporal envelope, is investigated in combination with thin foil targets in which recirculation of laser-accelerated electrons can lead to optimal conditions for coupling laser drive energy into the proton beam. This approach is shown to deliver a substantial enhancement in the coupling of laser energy to 5–30 MeV protons, compared to single pulse irradiation, reaching a record high 15% conversion efficiency with a temporal separation of 1 ps between the two pulses and a 5 μm-thick Au foil. A 1D simulation code is used to support and explain the origin of the observation of an optimum pulse separation of ∼1 ps.

  14. LiF TLD-100 as a Dosimeter in High Energy Proton Beam Therapy-Can It Yield Accurate Results?

    SciTech Connect

    Zullo, John R. Kudchadker, Rajat J.; Zhu, X. Ronald; Sahoo, Narayan; Gillin, Michael T.

    2010-04-01

    In the region of high-dose gradients at the end of the proton range, the stopping power ratio of the protons undergoes significant changes, allowing for a broad spectrum of proton energies to be deposited within a relatively small volume. Because of the potential linear energy transfer dependence of LiF TLD-100 (thermolumescent dosimeter), dose measurements made in the distal fall-off region of a proton beam may be less accurate than those made in regions of low-dose gradients. The purpose of this study is to determine the accuracy and precision of dose measured using TLD-100 for a pristine Bragg peak, particularly in the distal fall-off region. All measurements were made along the central axis of an unmodulated 200-MeV proton beam from a Probeat passive beam-scattering proton accelerator (Hitachi, Ltd., Tokyo, Japan) at varying depths along the Bragg peak. Measurements were made using TLD-100 powder flat packs, placed in a virtual water slab phantom. The measurements were repeated using a parallel plate ionization chamber. The dose measurements using TLD-100 in a proton beam were accurate to within {+-}5.0% of the expected dose, previously seen in our past photon and electron measurements. The ionization chamber and the TLD relative dose measurements agreed well with each other. Absolute dose measurements using TLD agreed with ionization chamber measurements to within {+-} 3.0 cGy, for an exposure of 100 cGy. In our study, the differences in the dose measured by the ionization chamber and those measured by TLD-100 were minimal, indicating that the accuracy and precision of measurements made in the distal fall-off region of a pristine Bragg peak is within the expected range. Thus, the rapid change in stopping power ratios at the end of the range should not affect such measurements, and TLD-100 may be used with confidence as an in vivo dosimeter for proton beam therapy.

  15. Beam diagnostics for high intensity hadron accelerators

    NASA Astrophysics Data System (ADS)

    Ausset, Patrick; Gardès, Daniel

    2007-07-01

    High intensity hadron beam accelerators have been recently proposed and developed either for the production of high intensity secondary beams for Nuclear and Particle Physics research (EURISOL, SPIRAL2, FAIR), or Applied Physics in the field of Accelerator Driven System and waste transmutation (EUROTRANS). For these applications, high power Linear Accelerator (LINAC) are planned to produce and accelerate hadron beams up to 1 GeV. Both commissioning and operation of these accelerators require dedicated beam instrumentation able to monitor and characterize on line as completely as possible the produced beams having a power in the range of 1 MW. Beam current, transverse beam centroı¨d position and profiles and beam energy are the most important characteristics that have to be measured. Due to the high average power of the beam, nondestructive or at least minimally intercepting beam sensors are required. Beam instrumentation for IPHI (CEA/DSM and CNRS/IN2P3 collaboration) which is a high intensity proton (3 MeV, 100 mA, CW operation) injector initially designed to be a possible front end for this kind of LINAC is under realization. Beam diagnostics already under operation, developments in progress will be described and will introduce a more general description of high power beam instrumentation.

  16. Fundamental Physics Explored with High Intensity Laser

    NASA Astrophysics Data System (ADS)

    Tajima, T.; Homma, K.

    2012-10-01

    Over the last century the method of particle acceleration to high energies has become the prime approach to explore the fundamental nature of matter in laboratory. It appears that the latest search of the contemporary accelerator based on the colliders shows a sign of saturation (or at least a slow-down) in increasing its energy and other necessary parameters to extend this frontier. We suggest two pronged approach enabled by the recent progress in high intensity lasers. First we envision the laser-driven plasma accelerator may be able to extend the reach of the collider. For this approach to bear fruit, we need to develop the technology of high averaged power laser in addition to the high intensity. For this we mention that the latest research effort of ICAN is an encouraging sign. In addition to this, we now introduce the concept of the noncollider paradigm in exploring fundamental physics with high intensity (and large energy) lasers. One of the examples we mention is the laser wakefield acceleration (LWFA) far beyond TeV without large luminosity. If we relax or do not require the large luminosity necessary for colliders, but solely in ultrahigh energy frontier, we are still capable of exploring such a fundamental issue. Given such a high energetic particle source and high-intensity laser fields simultaneously, we expect to be able to access new aspects on the matter and the vacuum structure from fundamental physical point of views. LWFA naturally exploits the nonlinear optical effects in the plasma when it becomes of relativistic intensity. Normally nonlinear optical effects are discussed based upon polarization susceptibility of matter to external fields. We suggest application of this concept even to the vacuum structure as a new kind of order parameter to discuss vacuum-originating phenomena at semimacroscopic scales. This viewpoint unifies the following observables with the unprecedented experimental environment we envision; the dispersion relation of

  17. Scaling of cross sections for K-electron capture by high-energy protons and alpha-particles from the multielectron atoms

    NASA Technical Reports Server (NTRS)

    Omidvar, K.

    1976-01-01

    Electron capture by protons from H, He, and the K-shell of Ar, and alpha particles from He are considered. It is shown that when a certain function of the experimental cross sections is plotted versus the inverse of the collision energy, at high energies the function falls on a straight line. At lower energies the function concaves up or down, depending on the charge of the projectile, the effective charge and the ionization potential of the electron that is being captured. The plot can be used to predict cross sections where experimental data are not available, and as a guide in future experiments. High energy scaling formulas for K-electron capture by low-charge projectiles are given.

  18. High-Energy-Resolution Inelastic Electron and Proton Scattering and the Multiphonon Nature of Mixed-Symmetry 2{sup +} States in {sup 94}Mo

    SciTech Connect

    Burda, O.; Kuhar, M.; Lenhardt, A.; Neumann-Cosel, P. von; Ponomarev, V. Yu.; Richter, A.; Wambach, J.; Botha, N.; Fearick, R. W.; Carter, J.; Sideras-Haddad, E.; Foertsch, S. V.; Neveling, R.; Smit, F. D.; Fransen, C.; Fujita, H.; Holt, J. D.; Pietralla, N.; Scholten, O.

    2007-08-31

    High-energy-resolution inelastic electron scattering (at the S-DALINAC) and proton scattering (at iThemba LABS) experiments permit a thorough test of the nature of proposed one- and two-phonon symmetric and mixed-symmetric 2{sup +} states of the nucleus {sup 94}Mo. The combined analysis reveals the one-phonon content of the mixed-symmetry state and its isovector character suggested by microscopic nuclear model calculations. The purity of two-phonon 2{sup +} states is extracted.

  19. The quantification of wound healing as a method to assess late radiation damage in primate skin exposed to high-energy protons

    NASA Astrophysics Data System (ADS)

    Cox, A. B.; Lett, J. T.

    In an experiment examining the effects of space radiations on primates, different groups of rhesus monkeys (Macaca mulatta) were exposed to single whole-body doses of 32- or 55-MeV protons. Survivors of those exposures, together with age-matched controls, have been monitored continuously since 1964 and 1965. Late effects of nominal proton doses ranging from 2-6 Gray have been measured in vitro using skin fibroblasts from the animals. A logical extension of that study is reported here, and it involves observations of wound healing after 3-mm diameter dermal punches were removed from the ears (pinnae) of control and irradiated monkeys. Tendencies in the reduction of competence to repair cutaneous wound have been revealed by the initial examinations of animals that received doses greater than 2 Gy more than 2 decades earlier. These trends indicate that this method of assessing radiation damage to skin exposed to high-energy radiations warrants further study.

  20. Ratio of aerosol and gases of radioactive chlorine and particle size distribution of aerosol formed by high-energy proton irradiation.

    PubMed

    Yokoyama, S; Sato, K; Manabe, K; Noguchi, H; Kaneko, H; Oki, Y; Iida, T; Tanaka, Su

    2007-01-01

    To estimate internal doses due to the inhalation of radionuclides produced by the nuclear spallation of the air nuclei in high-energy proton accelerator facilities, the physicochemical properties of radionuclides are very important. Thus, the ratio of aerosol and gases of 38Cl and 39Cl formed by irradiating argon gas-added air with a 48 MeV proton beam has been measured. Radionuclides of 38Cl and 39Cl exist as aerosol, acid gas and non-acid gas. The percentages of activity of 38Cl and 39Cl aerosols are about 80%. The number size distributions of non-radioactive aerosol were characterised by two peaks with diameters of 10-20 nm and larger than 20 nm. As a result predicted by a simple surface model, it was found that the activity size distribution of 38Cl aerosols can be regarded as that having a single peak at 120 nm. PMID:18033760

  1. Response of Cs2LiYCl6:Ce (CLYC) to High Energy Protons

    SciTech Connect

    Coupland, Daniel David Schechtman; Stonehill, Laura Catherine; Goett, John Jerome III

    2015-11-23

    Cs2LiYCl6:Ce (CLYC) is a promising new inorganic scintillator for gamma and neutron detection. As a gamma-ray detector, it exhibits bright light output and better resolution and proportionality of response than traditional gamma-ray scintillators such as NaI. It is also highly sensitive to thermal neutrons through capture on 6Li, and recent experiments have demonstrated sensitivity to fast neutrons through interactions with 35Cl. The response of CLYC to other forms of radiation has not been reported. We have performed the first measurements of the response of CLYC to several-hundred MeV protons. We have collected digitized waveforms from proton events, and compare to those produced by gammas and thermal neutrons. Finally, we discuss the potential for pulse shape discrimination between them.

  2. Effects of high energy x ray and proton irradiation on lead zirconate titanate thin films' dielectric and piezoelectric response

    SciTech Connect

    Bastani, Y.; Cortes-Pena, A. Y.; Wilson, A. D.; Gerardin, S.; Bagatin, M.; Paccagnella, A.; Bassiri-Gharb, N.

    2013-05-13

    The effects of irradiation by X rays and protons on the dielectric and piezoelectric response of highly (100)-textured polycrystalline Pb(Zr{sub x}Ti{sub 1-x})O{sub 3} (PZT) thin films have been studied. Low-field dielectric permittivity, remanent polarization, and piezoelectric d{sub 33,f} response all degraded with exposure to radiation, for doses higher than 300 krad. At first approximation, the degradation increased at higher radiation doses, and was stronger in samples exposed to X rays, compared to the proton-irradiated ones. Nonlinear and high-field dielectric characterization suggest a radiation-induced reduction of the extrinsic contributions to the response, attributed to increased pinning of the domain walls by the radiation-induced point defects.

  3. Duke University high energy physics

    SciTech Connect

    Fortney, L.R.; Goshaw, A.T.; Walker, W.D.

    1992-07-01

    This Progress Report presents a review of the research done in 1992 by the Duke High Energy Physics Group. This is the first year of a three-year grant which was approved by the Office of High Energy Physics at DOE after an external review of our research program during the summer of 1991. Our research is centered at Fermilab where we are involved with two active experiments, one using the Tevatron collider (CDF, the Collider Detector Facility) and the other using a proton beam in the high intensity laboratory (E771, study of beauty production). In addition to these running experiments we are continuing the analysis of data from experiments E735 (collider search for a quark-gluon plasma), E705 (fixed target study of direct photon and {sub {Chi}} meson production) and E597 (particle production from hadron-nucleus collisions). Finally, this year has seen an expansion of our involvement with the design of the central tracking detector for the Solenoidal Detector Collaboration (SDC) and an increased role in the governance of the collaboration. Descriptions of these research activities are presented in this report.

  4. High intensity neutrino oscillation facilities in Europe

    NASA Astrophysics Data System (ADS)

    Edgecock, T. R.; Caretta, O.; Davenne, T.; Densam, C.; Fitton, M.; Kelliher, D.; Loveridge, P.; Machida, S.; Prior, C.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.; Wildner, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoni, S.; Hansen, C.; Benedetto, E.; Jensen, E.; Kosmicki, A.; Martini, M.; Osborne, J.; Prior, G.; Stora, T.; Melo Mendonca, T.; Vlachoudis, V.; Waaijer, C.; Cupial, P.; Chancé, A.; Longhin, A.; Payet, J.; Zito, M.; Baussan, E.; Bobeth, C.; Bouquerel, E.; Dracos, M.; Gaudiot, G.; Lepers, B.; Osswald, F.; Poussot, P.; Vassilopoulos, N.; Wurtz, J.; Zeter, V.; Bielski, J.; Kozien, M.; Lacny, L.; Skoczen, B.; Szybinski, B.; Ustrycka, A.; Wroblewski, A.; Marie-Jeanne, M.; Balint, P.; Fourel, C.; Giraud, J.; Jacob, J.; Lamy, T.; Latrasse, L.; Sortais, P.; Thuillier, T.; Mitrofanov, S.; Loiselet, M.; Keutgen, Th.; Delbar, Th.; Debray, F.; Trophine, C.; Veys, S.; Daversin, C.; Zorin, V.; Izotov, I.; Skalyga, V.; Burt, G.; Dexter, A. C.; Kravchuk, V. L.; Marchi, T.; Cinausero, M.; Gramegna, F.; De Angelis, G.; Prete, G.; Collazuol, G.; Laveder, M.; Mazzocco, M.; Mezzetto, M.; Signorini, C.; Vardaci, E.; Di Nitto, A.; Brondi, A.; La Rana, G.; Migliozzi, P.; Moro, R.; Palladino, V.; Gelli, N.; Berkovits, D.; Hass, M.; Hirsh, T. Y.; Schaumann, M.; Stahl, A.; Wehner, J.; Bross, A.; Kopp, J.; Neuffer, D.; Wands, R.; Bayes, R.; Laing, A.; Soler, P.; Agarwalla, S. K.; Cervera Villanueva, A.; Donini, A.; Ghosh, T.; Gómez Cadenas, J. J.; Hernández, P.; Martín-Albo, J.; Mena, O.; Burguet-Castell, J.; Agostino, L.; Buizza-Avanzini, M.; Marafini, M.; Patzak, T.; Tonazzo, A.; Duchesneau, D.; Mosca, L.; Bogomilov, M.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Akhmedov, E.; Blennow, M.; Lindner, M.; Schwetz, T.; Fernández Martinez, E.; Maltoni, M.; Menéndez, J.; Giunti, C.; González García, M. C.; Salvado, J.; Coloma, P.; Huber, P.; Li, T.; López Pavón, J.; Orme, C.; Pascoli, S.; Meloni, D.; Tang, J.; Winter, W.; Ohlsson, T.; Zhang, H.; Scotto-Lavina, L.; Terranova, F.; Bonesini, M.; Tortora, L.; Alekou, A.; Aslaninejad, M.; Bontoiu, C.; Kurup, A.; Jenner, L. J.; Long, K.; Pasternak, J.; Pozimski, J.; Back, J. J.; Harrison, P.; Beard, K.; Bogacz, A.; Berg, J. S.; Stratakis, D.; Witte, H.; Snopok, P.; Bliss, N.; Cordwell, M.; Moss, A.; Pattalwar, S.; Apollonio, M.

    2013-02-01

    The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fréjus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of μ+ and μ- beams in a storage ring. The far detector in this case is a 100 kt magnetized iron neutrino detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular He6 and Ne18, also stored in a ring. The far detector is also the MEMPHYS detector in the Fréjus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the physics reach of each facility, in particular for the measurement of CP violation in the lepton sector, and estimated the cost of construction. These have demonstrated that the best facility to build is the Neutrino Factory. However, if a powerful proton driver is constructed for another purpose or if the MEMPHYS detector is built for astroparticle physics, the Super Beam also becomes very attractive.

  5. Study of crosslinking onset and hydrogen annealing of ultra-high molecular weight polyethylene irradiated with high-energy protons

    NASA Astrophysics Data System (ADS)

    Wilson, John Ford

    1997-09-01

    Ultra high molecular weight polyethylene (UHMW-PE) is used extensively in hip and knee endoprostheses. Radiation damage from the sterilization of these endoprostheses prior to surgical insertion results in polymer crosslinking and decreased oxidative stability. The motivation for this study was to determine if UHMW-PE could be crosslinked by low dose proton irradiation with minimal radiation damage and its subsequent deleterious effects. I found that low dose proton irradiation and post irradiation hydrogen annealing did crosslink UHMW-PE and limit post irradiation oxidation. Crosslinking onset was investigated for UHMW-PE irradiated with 2.6 and 30 MeV H+ ions at low doses from 5.7 × 1011-2.3 × 1014 ions/cm2. Crosslinking was determined from gel permeation chromatography (GPC) of 1,2,4 trichlorobenzene sol fractions and increased with dose. Fourier transform infrared spectroscopy (FTIR) showed irradiation resulted in increased free radicals confirmed from increased carbonyl groups. Radiation damage, especially at the highest doses observed, also showed up in carbon double bonds and increased methyl end groups. Hydrogen annealing after ion irradiation resulted in 40- 50% decrease in FTIR absorption associated with carbonyl. The hydrogen annealing prevented further oxidation after aging for 1024 hours at 80oC. Hydrogen annealing was successful in healing radiation damage through reacting with the free radicals generated during proton irradiation. Polyethylenes, polyesters, and polyamides are used in diverse applications by the medical profession in the treatment of orthopedic impairments and cardiovascular disease and for neural implants. These artificial implants are sterilized with gamma irradiation prior to surgery and the resulting radiation damage can lead to accelerated deterioration of the implant properties. The findings in this study will greatly impact the continued use of these materials through the elimination of many problems associated with radiation

  6. Cross sections for proton induced high energy γ -ray emission (PIGE) in reaction 19 F(p, αγ)16 O at incident proton energies between 1.5 and 4 MeV

    NASA Astrophysics Data System (ADS)

    Cabanelas, P.; Cruz, J.; Fonseca, M.; Henriques, A.; Lourenço, F.; Luís, H.; Machado, J.; Pires Ribeiro, J.; Sánchez-Benítez, A. M.; Teubig, P.; Velho, P.; Zarza-Moreno, M.; Galaviz, D.; Jesus, A. P.

    2016-08-01

    We have studied the high energy gamma-rays produced in the reaction 19 F(p, αγ)16 O for incident proton energies from 1.5 to 4.0 MeV over NaF/Ag and CaF2/Ag thin targets in two different sets of data. Gamma-rays were detected with a High Purity Ge detector with an angle of 130° with respect to the beam axis. The cross-sections for the high energy gamma-rays of 6.129, 6.915 and 7.115 MeV have been measured for the whole group between 5 and 7.2 MeV with accuracy better than 10%. A new energy range was covered and more points are included in the cross-sections data base expanding the existing set of data. Results are in agreement with previous measurements in similar conditions.

  7. High Intensity Polarized Electron Gun

    SciTech Connect

    Redwine, Robert P.

    2012-07-31

    The goal of the project was to investigate the possibility of building a very high intensity polarized electron gun for the Electron-Ion Collider. This development is crucial for the eRHIC project. The gun implements a large area cathode, ring-shaped laser beam and active cathode cooling. A polarized electron gun chamber with a large area cathode and active cathode cooling has been built and tested. A preparation chamber for cathode activation has been built and initial tests have been performed. Major parts for a load-lock chamber, where cathodes are loaded into the vacuum system, have been manufactured.

  8. 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.

  9. Preplasma effects on the generation of high-energy protons in ultraintense laser interaction with foil targets

    SciTech Connect

    Zheng, F. L.; Huang, T. W.; Wu, S. Z.; Zhang, H.; He, X. T.; Institute of Applied Physics and Computational Mathematics, Beijing 100088 ; Yu, M. Y.; Institut für Theoretische Physik I, Ruhr-Universität Bochum, D-44780 Bochum ; Zhou, C. T.; Institute of Applied Physics and Computational Mathematics, Beijing 100088; Science College, National University of Defense Technology, Changsha 410073

    2013-12-15

    It is shown that the intense quasistatic electric and magnetic fields self-generated near the axis of the laser-driven channel in an appropriately profiled preplasma during ultraintense laser interaction with a thin target can create dense relativistic electron bunches. The latter easily penetrate through the target and can greatly enhance the sheath field at the rear, resulting in significant increase in the laser-to-ion energy conversion efficiency and the maximum energy of the target normal sheath accelerated ions. Particle-in-cell simulations show that with a hydrogen targets a proton beam of peak energy ∼38 MeV and energy conversion efficiency ≥6.5% can be produced by a linearly polarized 5 × 10{sup 19} W/cm{sup 2} laser. An analytical model is also proposed and its results agree well with those of the simulations.

  10. Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy-density plasmas

    SciTech Connect

    Li, C. K.; Seguin, F. H.; Frenje, J. A.; Manuel, M.; Casey, D.; Sinenian, N.; Petrasso, R. D.; Amendt, P. A.; Landen, O. L.; Rygg, J. R.; Town, R. P. J.; Betti, R.; Meyerhofer, D. D.; Delettrez, J.; Knauer, J. P.; Marshall, F.; Sangster, T. C.; Smalyuk, V. A.; Soures, J. M.; Shvarts, D.

    2009-05-15

    Time-gated, monoenergetic-proton radiography provides unique measurements of the electric (E) and magnetic (B) fields produced in laser-foil interactions and during the implosion of inertial-confinement-fusion capsules. These experiments resulted in the first observations of several new and important features: (1) observations of the generation, decay dynamics, and instabilities of megagauss B fields in laser-driven planar plastic foils, (2) the observation of radial E fields inside an imploding capsule, which are initially directed inward, reverse direction during deceleration, and are likely related to the evolution of the electron pressure gradient, and (3) the observation of many radial filaments with complex electromagnetic field striations in the expanding coronal plasmas surrounding the capsule. The physics behind and implications of such observed fields are discussed.

  11. Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy-density plasmas

    SciTech Connect

    Li, C. K.; Séguin, F. H.; Frenje, J. A.; Manuel, M.; Casey, D.; Sinenian, N.; Petrasso, R. D.; Amendt, P. A.; Landen, O. L.; Rygg, J. R.; Town, R. P. J.; Betti, R.; Delettrez, J.; Knauer, J. P.; Marshall, F.; Meyerhofer, D. D.; Sangster, T. C.; Shvarts, D.; Smalyuk, V. A.; Soures, J. M.; Back, C. A.; Kilkenny, J. D.; Nikroo, A.

    2009-01-01

    Time-gated, monoenergetic-proton radiography provides unique measurements of the electric (E) and magnetic (B) fields produced in laser-foil interactions and during the implosion of inertial-confinement-fusion capsules. These experiments resulted in the first observations of several new and important features: (1) observations of the generation, decay dynamics, and instabilities of megagauss B fields in laser-driven planar plastic foils, (2) the observation of radial E fields inside an imploding capsule, which are initially directed inward, reverse direction during deceleration, and are likely related to the evolution of the electron pressure gradient, and (3) the observation of many radial filaments with complex electromagnetic field striations in the expanding coronal plasmas surrounding the capsule. The physics behind and implications of such observed fields are discussed.

  12. Preplasma effects on the generation of high-energy protons in ultraintense laser interaction with foil targets

    NASA Astrophysics Data System (ADS)

    Zheng, F. L.; Wu, S. Z.; Zhang, H.; Huang, T. W.; Yu, M. Y.; Zhou, C. T.; He, X. T.

    2013-12-01

    It is shown that the intense quasistatic electric and magnetic fields self-generated near the axis of the laser-driven channel in an appropriately profiled preplasma during ultraintense laser interaction with a thin target can create dense relativistic electron bunches. The latter easily penetrate through the target and can greatly enhance the sheath field at the rear, resulting in significant increase in the laser-to-ion energy conversion efficiency and the maximum energy of the target normal sheath accelerated ions. Particle-in-cell simulations show that with a hydrogen targets a proton beam of peak energy ˜38 MeV and energy conversion efficiency ≥6.5% can be produced by a linearly polarized 5 × 1019 W/cm2 laser. An analytical model is also proposed and its results agree well with those of the simulations.

  13. Thermal stability of deep level defects induced by high energy proton irradiation in n-type GaN

    SciTech Connect

    Zhang, Z.; Farzana, E.; Sun, W. Y.; Arehart, A. R.; Ringel, S. A.; Chen, J.; Zhang, E. X.; Fleetwood, D. M.; Schrimpf, R. D.; McSkimming, B.; Kyle, E. C. H.; Speck, J. S.

    2015-10-21

    The impact of annealing of proton irradiation-induced defects in n-type GaN devices has been systematically investigated using deep level transient and optical spectroscopies. Moderate temperature annealing (>200–250 °C) causes significant reduction in the concentration of nearly all irradiation-induced traps. While the decreased concentration of previously identified N and Ga vacancy related levels at E{sub C} − 0.13 eV, 0.16 eV, and 2.50 eV generally followed a first-order reaction model with activation energies matching theoretical values for N{sub I} and V{sub Ga} diffusion, irradiation-induced traps at E{sub C} − 0.72 eV, 1.25 eV, and 3.28 eV all decrease in concentration in a gradual manner, suggesting a more complex reduction mechanism. Slight increases in concentration are observed for the N-vacancy related levels at E{sub C} − 0.20 eV and 0.25 eV, which may be due to the reconfiguration of other N-vacancy related defects. Finally, the observed reduction in concentrations of the states at E{sub C} − 1.25 and E{sub C} − 3.28 eV as a function of annealing temperature closely tracks the detailed recovery behavior of the background carrier concentration as a function of annealing temperature. As a result, it is suggested that these two levels are likely to be responsible for the underlying carrier compensation effect that causes the observation of carrier removal in proton-irradiated n-GaN.

  14. Development of methods for calculating basic features of the nuclear contribution to single event upsets under the effect of protons of moderately high energy

    SciTech Connect

    Chechenin, N. G. Chuvilskaya, T. V.; Shirokova, A. A.; Kadmenskii, A. G.

    2015-10-15

    As a continuation and a development of previous studies of our group that were devoted to the investigation of nuclear reactions induced by protons of moderately high energy (between 10 and 400 MeV) in silicon, aluminum, and tungsten atoms, the results obtained by exploring nuclear reactions on atoms of copper, which is among the most important components in materials for contact pads and pathways in modern and future ultralarge-scale integration circuits, especially in three-dimensional topology, are reported in the present article. The nuclear reactions in question lead to the formation of the mass and charge spectra of recoil nuclei ranging fromheavy target nuclei down to helium and hydrogen. The kineticenergy spectra of reaction products are calculated. The results of the calculations based on the procedure developed by our group are compared with the results of calculations and experiments performed by other authors.

  15. The relation between the fundamental scale controlling high-energy interactions of quarks and the proton mass

    SciTech Connect

    Deur, Alexandre; Brodsky, Stanley J.; de Teramond, Guy F.

    2015-04-06

    Quantum Chromodynamics (QCD) provides a fundamental description of the physics binding quarks into protons, neutrons, and other hadrons. QCD is well understood at short distances where perturbative calculations are feasible. Establishing an explicit relation between this regime and the large-distance physics of quark confinement has been a long-sought goal. A major challenge is to relate the parameter Λs, which controls the predictions of perturbative QCD (pQCD) at short distances, to the masses of hadrons. Here we show how new theoretical insights into QCD's behavior at large and small distances lead to an analytical relation between hadronic masses and Λs. The resulting prediction, Λs = 0.341 ± 0.024 GeV agrees well with the experimental value 0.339 ± 0.016 GeV. Conversely, the experimental value of Λs can be used to predict the masses of hadrons, a task which had so far only been accomplished through intensive numerical lattice calculations, requiring several phenomenological input parameters.

  16. AGS RESONANT EXTRACTION WITH HIGH INTENSITY BEAMS.

    SciTech Connect

    AHRENS,L.; BROWN,K.; GLENN,J.W.; ROSER,T.; TSOUPAS,N.; VANASSELT,W.

    1999-03-29

    The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7 x 10{sup 13} protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams.[1] Learning to extract and transport these higher intensity beams has required a process of careful modeling and experimentation. We have had to learn how to correct for various instabilities and how to better match extraction and the transport lines to the higher emittance beams being accelerated in the AGS. Techniques employed include ''RF'' methods to smooth out momentum distributions and fine structure. We will present results of detailed multi-particle tracking modeling studies which enabled us to develop a clear understanding of beam loss mechanisms in the transport and extraction process. We will report on our status, experiences, and the present understanding of the intensity limitations imposed by resonant extraction and transport to fixed target stations.

  17. Measurement of K+ production cross section by 8 GeV protons using high energy neutrino interactions in the SciBooNE detector

    SciTech Connect

    Cheng, G.

    2011-07-28

    The SciBooNE Collaboration reports K+ production cross section and rate measurements using high energy daughter muon neutrino scattering data off the SciBar polystyrene (C8H8) target in the SciBooNE detector. The K+ mesons are produced by 8 GeV protons striking a beryllium target in Fermilab Booster Neutrino Beam line (BNB). Using observed neutrino and antineutrino events in SciBooNE, we measure d2σ/dpdΩ = (5.34 ±0.76) mb/(GeV/c x sr) for p + Be =K+ + X at mean K+ energy of 3.9 GeV and angle (with respect to the proton beam direction) of 3.7 degrees, corresponding to the selected K+ sample. Compared to Monte Carlo predictions using previous higher energy K+ production measurements, this measurement, which uses the NUANCE neutrino interaction generator, is consistent with a normalization factor of 0.85 ± 0.12. This agreement is evidence that the extrapolation of the higher energy K+ measurements to an 8 GeV beam energy using Feynman scaling is valid. This measurement reduces the error on the K+ production cross section from 40% to 14%.

  18. Measurement of K+ production cross section by 8 GeV protons using high energy neutrino interactions in the SciBooNE detector

    DOE PAGESBeta

    Cheng, G.

    2011-07-28

    The SciBooNE Collaboration reports K+ production cross section and rate measurements using high energy daughter muon neutrino scattering data off the SciBar polystyrene (C8H8) target in the SciBooNE detector. The K+ mesons are produced by 8 GeV protons striking a beryllium target in Fermilab Booster Neutrino Beam line (BNB). Using observed neutrino and antineutrino events in SciBooNE, we measure d2σ/dpdΩ = (5.34 ±0.76) mb/(GeV/c x sr) for p + Be =K+ + X at mean K+ energy of 3.9 GeV and angle (with respect to the proton beam direction) of 3.7 degrees, corresponding to the selected K+ sample. Compared tomore » Monte Carlo predictions using previous higher energy K+ production measurements, this measurement, which uses the NUANCE neutrino interaction generator, is consistent with a normalization factor of 0.85 ± 0.12. This agreement is evidence that the extrapolation of the higher energy K+ measurements to an 8 GeV beam energy using Feynman scaling is valid. This measurement reduces the error on the K+ production cross section from 40% to 14%.« less

  19. The Relativistic Electron-Proton Telescope (REPT) Instrument on Board the Radiation Belt Storm Probes (RBSP) Spacecraft: Characterization of Earth's Radiation Belt High-Energy Particle Populations

    NASA Astrophysics Data System (ADS)

    Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Batiste, S.; Bolton, M.; Li, X.; Elkington, S. R.; Monk, S.; Reukauf, R.; Steg, S.; Westfall, J.; Belting, C.; Bolton, B.; Braun, D.; Cervelli, B.; Hubbell, K.; Kien, M.; Knappmiller, S.; Wade, S.; Lamprecht, B.; Stevens, K.; Wallace, J.; Yehle, A.; Spence, H. E.; Friedel, R.

    2013-11-01

    Particle acceleration and loss in the million electron Volt (MeV) energy range (and above) is the least understood aspect of radiation belt science. In order to measure cleanly and separately both the energetic electron and energetic proton components, there is a need for a carefully designed detector system. The Relativistic Electron-Proton Telescope (REPT) on board the Radiation Belt Storm Probe (RBSP) pair of spacecraft consists of a stack of high-performance silicon solid-state detectors in a telescope configuration, a collimation aperture, and a thick case surrounding the detector stack to shield the sensors from penetrating radiation and bremsstrahlung. The instrument points perpendicular to the spin axis of the spacecraft and measures high-energy electrons (up to ˜20 MeV) with excellent sensitivity and also measures magnetospheric and solar protons to energies well above E=100 MeV. The instrument has a large geometric factor ( g=0.2 cm2 sr) to get reasonable count rates (above background) at the higher energies and yet will not saturate at the lower energy ranges. There must be fast enough electronics to avert undue dead-time limitations and chance coincidence effects. The key goal for the REPT design is to measure the directional electron intensities (in the range 10-2-106 particles/cm2 s sr MeV) and energy spectra (Δ E/ E˜25 %) throughout the slot and outer radiation belt region. Present simulations and detailed laboratory calibrations show that an excellent design has been attained for the RBSP needs. We describe the engineering design, operational approaches, science objectives, and planned data products for REPT.

  20. Formation of amino acids and nucleic acid constituents from simulated primitive planetary atmospheres by irradiation with high-energy protons

    NASA Astrophysics Data System (ADS)

    Kobayashi, K.; Yamanashi, H.; Ohashi, A.; Kaneko, T.; Miyakawa, S.; Saito, T.

    It is suggested that primitive Earth atmosphere was only slightly reduced, which w as composed of carbon dioxide, carbon monoxide, nitrogen and water. It has been shown that bioorganic compounds can be hardly formed by energies as UV light, heat and spark discharges. We therefore examined possible formation pat hways of bioorganic compounds in the primitive E arth. A mixt ure of carbon monoxide, nitrogen and water was irradiated with high-energy prot ons generated by a van de Graaff accelerator, whi c h simulated an action of cosm ic rays. Aqueous solution of the product was hydr olyzed, and then analyzed by chromatography and mass spectrometry. A wide variety of amino acids and uracil, one of the nucle ic acid bases, wer e identified. Ribose, the RNA sugar, has not been identified, but formation of reducing polyols was suggested. A mino acids and uracil were also formed from a mixture of carbo n dioxide, carbon monoxide, nitrogen and water, and their yields correlated to the ratio of carbon monoxide and nitrogen in the mixture. Since a certain percentage of carbon monoxide could be expected to be in it [1], cosmic radiation can be regarded as an effective energ so urce for prebiotic formation of life's building blocks in they primitive Earth [2]. In the conventional scenario of chemical evolution, amino acids were formed in t he primitive ocean from such intermediates as HCN an d HCHO formed in t he atmosphere. T his scenario seem s not to be possible due to the following reasons: (1) The irradiation products were quit e complex organic com pound s whose molecular weights were ca. 1000, and they gave amino acids after hydrolysis. (2) Energy yields of amino ac ids in the hydrolysates were comparable to those of HCN and HCHO in the irradiation pro duct s. (3) Irradiation products from a mixture of carbon monoxide and nitrogen without water als o gave amino acids aft er hydrolysis. T hes e observations strongly sugge s t e d that complex precursors of bioor ganic com

  1. Multifactorial Resistance of Bacillus subtilis Spores to High-Energy Proton Radiation: Role of Spore Structural Components and the Homologous Recombination and Non-Homologous End Joining DNA Repair Pathways

    PubMed Central

    Reitz, Günther; Li, Zuofeng; Klein, Stuart; Nicholson, Wayne L.

    2012-01-01

    Abstract The space environment contains high-energy charged particles (e.g., protons, neutrons, electrons, α-particles, heavy ions) emitted by the Sun and galactic sources or trapped in the radiation belts. Protons constitute the majority (87%) of high-energy charged particles. Spores of Bacillus species are one of the model systems used for astro- and radiobiological studies. In this study, spores of different Bacillus subtilis strains were used to study the effects of high energetic proton irradiation on spore survival. Spores of the wild-type B. subtilis strain [mutants deficient in the homologous recombination (HR) and non-homologous end joining (NHEJ) DNA repair pathways and mutants deficient in various spore structural components such as dipicolinic acid (DPA), α/β-type small, acid-soluble spore protein (SASP) formation, spore coats, pigmentation, or spore core water content] were irradiated as air-dried multilayers on spacecraft-qualified aluminum coupons with 218 MeV protons [with a linear energy transfer (LET) of 0.4 keV/μm] to various final doses up to 2500 Gy. Spores deficient in NHEJ- and HR-mediated DNA repair were significantly more sensitive to proton radiation than wild-type spores, indicating that both HR and NHEJ DNA repair pathways are needed for spore survival. Spores lacking DPA, α/β-type SASP, or with increased core water content were also significantly more sensitive to proton radiation, whereas the resistance of spores lacking pigmentation or spore coats was essentially identical to that of the wild-type spores. Our results indicate that α/β-type SASP, core water content, and DPA play an important role in spore resistance to high-energy proton irradiation, suggesting their essential function as radioprotectants of the spore interior. Key Words: Bacillus—Spores—DNA repair—Protection—High-energy proton radiation. Astrobiology 12, 1069–1077. PMID:23088412

  2. High intensity portable fluorescent light

    NASA Technical Reports Server (NTRS)

    Kendall, F. B.

    1972-01-01

    Eight high intensity portable fluorescent lights were produced. Three prototype lights were also produced, two of which were subsequently updated to the physical and operational configuration of the qualification and flight units. Positioning of lamp apertures and reflectors in these lights is such that the light is concentrated and intensified in a specific pattern rather than widely diffused. Indium amalgam control of mercury vapor pressure in the lamp gives high output at lamp ambient temperatures up to 105 C. A small amount of amalgam applied to each electrode stem helps to obtain fast warm-up. Shrinking a Teflon sleeve on the tube and potting metal caps on each end of the lamp minimizes dispersion of mercury vapor and glass particles in the event of accidental lamp breakage. Operation at 20 kHz allows the lamps to consume more power than at low frequency, thus increasing their light output and raising their efficiency. When used to expose color photographic film, light from the lamps produces results approximately equal to sunlight.

  3. Longitudinal laser ion acceleration in low density targets: experimental optimization on the Titan laser facility and numerical investigation of the ultra-high intensity limit

    NASA Astrophysics Data System (ADS)

    d'Humières, E.; Chen, S.; Lobet, Mathieu; Sciscio, M.; Antici, Patrizio; Bailly-Grandvaux, Mathieu; Gangolf, Thomas; Revet, Guilhem; Santos, Joao J.; Schroer, Anna-Marie; Willi, O.; Tikhonchuk, Vladimir T.; Pepin, Henri; Fuchs, Julien

    2015-05-01

    Recent theoretical and experimental studies suggest the possibility of enhancing the efficiency and ease of laser acceleration of protons and ions using underdense or near critical plasmas through electrostatic shocks. Very promising results were recently obtained in this regime. In these experiments, a first ns pulse was focused on a thin target to explode it and a second laser with a high intensity was focused on the exploded foil. The delay between two lasers allowed to control the density gradient seen by the second laser pulse. The transition between various laser ion acceleration regimes depending on the density gradient length was studied. With a laser energy of a few Joules, protons with energies close to the energies of TNSA accelerated protons were obtained for various exploded foils configurations. In the high energy regime (~180 J), protons with energies significantly higher than the ones of TNSA accelerated protons were obtained when exploding the foil while keeping a good beam quality. These results demonstrate that low-density targets are promising candidates for an efficient proton source that can be optimized by choosing appropriate plasma conditions. New experiments were also performed in this regime with gas jets. Scaling shock acceleration in the low density regime to ultra high intensities is a challenge as radiation losses and electron positron pair production change the optimization of the shock process. Using large-scale Particle-In-Cell simulations, the transition to this regime in which intense beams of relativistic ions can be produced is investigated.

  4. Beam diagnostics at high-intensity storage rings

    SciTech Connect

    Plum, M.

    1993-11-01

    Beam diagnostics at high-intensity facilities feature their own special set of problems and characteristics. Issues peculiar to high-intensity storage rings include beam loss, beam halos, extraction efficiency, beam in the gap, clearing electrodes, and beam-profile measurement. The Los Alamos Proton Storage Ring (PSR) is a nice example of a high-intensity storage ring. The author discusses in some detail three diagnostic systems currently in use at the PSR: the beam-loss-monitor system, the electron-clearing system, and the beam-in-the-gap monitor. Much of the discussion is inspired by the problems that were encountered and the useful things learned while commissioning and developing the PSR. Another inspiration is the work on the next-generation neutron-spallation source, also known as the National Center for Neutron Research (NCNR).

  5. Beam diagnostics at high-intensity storage rings

    SciTech Connect

    Plum, M. )

    1994-10-10

    Beam diagnostics at high-intensity facilities feature their own special set of problems and characteristics, issues peculiar to high-intensity storage rings include beam loss, beam halos, extraction efficiency, beam in the gap, clearing electrodes, and beam-profile measurement. The Los Alamos Proton Storage Ring (PSR) is a nice example of a high-intensity storage ring. I will discuss in some detail three diagnostic systems currently in use at the PSR: the beam-loss-monitor system, the electron-clearing system, and the beam-in-the-gap monitor. Much of our discussion is inspired by the problems we have encountered and the useful things we have learned while commissioning and developing the PSR. Another inspiration is our work on the next-generation neutron-spallation source, also known as the National Center for Neutron Research (NCNR).

  6. Correlation of radiation-induced changes in mechanical properties and microstructural development of Alloy 718 irradiated with mixed spectra of high-energy protons and spallation neutrons

    NASA Astrophysics Data System (ADS)

    Sencer, B. H.; Bond, G. M.; Garner, F. A.; Hamilton, M. L.; Maloy, S. A.; Sommer, W. F.

    2001-07-01

    Alloy 718 is a γ '(Ni 3(Al,Ti))-γ″(Ni 3Nb) hardenable superalloy with attractive strength, and corrosion resistance. This alloy is a candidate material for use in accelerator production of tritium (APT) target and blanket applications, where it would have to withstand low-temperature irradiation by high-energy protons and spallation neutrons. The existing data base, relevant to such irradiation conditions, is very limited. Alloy 718 has therefore been exposed to a particle flux and spectrum at the Los Alamos Neutron Science Center (LANSCE), closely matching those expected in the APT target and blanket applications. The yield stress of Alloy 718 increases with increasing dose up to ˜0.5 dpa, and then decreases with further increase in dose. The uniform elongation, however, drastically decreases with increasing dose at very low doses (<0.5 dpa), and does not recover when the alloy later softens somewhat. Transmission electron microscopy (TEM) investigation of Alloy 718 shows that superlattice spots corresponding to the age-hardening precipitate phases γ ' and γ″ are lost from the diffraction patterns for Alloy 718 by only 0.6 dpa, the lowest proton-induced dose level achieved in this experiment. Examination of samples that were neutron irradiated to doses of only ˜0.1 dpa showed that precipitates are faintly visible in diffraction patterns but are rapidly becoming invisible. It is proposed that the γ ' and γ″ first become disordered (by <0.6 dpa), but remain as solute-rich aggregates that still contribute to the hardness at relatively low dpa levels, and then are gradually dispersed at higher doses.

  7. Spallation neutron source and other high intensity froton sources

    SciTech Connect

    Weiren Chou

    2003-02-06

    This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under construction and proposed is also given. An R&D program is included in an appendix.

  8. High Intensity Polarized Electron Sources

    NASA Astrophysics Data System (ADS)

    Poelker, M.; Adderley, P.; Brittian, J.; Clark, J.; Grames, J.; Hansknecht, J.; McCarter, J.; Stutzman, M. L.; Suleiman, R.; Surles-Law, K.

    2008-02-01

    During the 1990s, at numerous facilities world wide, extensive R&D devoted to constructing reliable GaAs photoguns helped ensure successful accelerator-based nuclear and high-energy physics programs using spin polarized electron beams. Today, polarized electron source technology is considered mature, with most GaAs photoguns meeting accelerator and experiment beam specifications in a relatively trouble-free manner. Proposals for new collider facilities however, require electron beams with parameters beyond today's state-of-the-art and serve to renew interest in conducting polarized electron source R&D. And at CEBAF/Jefferson Lab, there is an immediate pressing need to prepare for new experiments that require considerably more beam current than before. One experiment in particular—Q-weak, a parity violation experiment that will look for physics beyond the Standard Model—requires 180 uA average current at polarization >80% for a duration of one year, with run-averaged helicity correlated current asymmetry less than 0.1 ppm. Neighboring halls will continue taking beam during Q-weak, pushing the total average beam current from the gun beyond 300 uA. This workshop contribution describes R&D at Jefferson Lab, dedicated toward extending the operating current of polarized electron sources to meet the requirements of high current experiments at CEBAF and to better appreciate the technological challenges of new accelerators, particularly high average current machines like eRHIC that require at least 25 mA at high polarization.

  9. High energy electron cooling

    SciTech Connect

    Parkhomchuk, V.

    1997-09-01

    High energy electron cooling requires a very cold electron beam. The questions of using electron cooling with and without a magnetic field are presented for discussion at this workshop. The electron cooling method was suggested by G. Budker in the middle sixties. The original idea of the electron cooling was published in 1966. The design activities for the NAP-M project was started in November 1971 and the first run using a proton beam occurred in September 1973. The first experiment with both electron and proton beams was started in May 1974. In this experiment good result was achieved very close to theoretical prediction for a usual two component plasma heat exchange.

  10. Absolute calibration of photostimulable image plate detectors used as (0.5-20 MeV) high-energy proton detectors.

    PubMed

    Mancić, A; Fuchs, J; Antici, P; Gaillard, S A; Audebert, P

    2008-07-01

    In this paper, the absolute calibration of photostimulable image plates (IPs) used as proton detectors is presented. The calibration is performed in a wide range of proton energies (0.5-20 MeV) by exposing simultaneously the IP and calibrated detectors (radiochromic films and solid state detector CR39) to a source of broadband laser-accelerated protons, which are spectrally resolved. The final result is a calibration curve that enables retrieving the proton number from the IP signal. PMID:18681694

  11. Theoretical study of the effect of the size of a high-energy proton beam of the Large Hadron Collider on the formation and propagation of shock waves in copper irradiated by 450-GeV proton beams

    NASA Astrophysics Data System (ADS)

    Ryazanov, A. I.; Stepakov, A. V.; Vasilyev, Ya. S.; Ferrari, A.

    2014-02-01

    The interaction of 450-GeV protons with copper, which is the material of the collimators of the Large Hadron Collider, has been theoretically studied. A theoretical model for the formation and propagation of shock waves has been proposed on the basis of the analysis of the energy released by a proton beam in the electronic subsystem of the material owing to the deceleration of secondary particles appearing in nuclear reactions induced by this beam on the electronic subsystem of the material. The subsequent transfer of the energy from the excited electronic subsystem to the crystal lattice through the electron-phonon interaction has been described within the thermal spike model [I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, Sov. Phys. JETP 4, 173 (1957); I.M. Lifshitz, M.I. Kaganov, and L.V. Tanatarov, At. Energ. 6, 391 (1959); K. Yasui, Nucl. Instrum. Methods Phys. Res., Sect. B 90, 409 (1994)]. The model of the formation of shock waves involves energy exchange processes between excited electronic and ionic subsystems of the irradiated material and is based on the hydrodynamic approximation proposed by Zel'dovich [Ya.B. Zel'dovich and Yu.P. Raizer, Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena (Nauka, Moscow, 1966; Dover, New York, 2002)]. This model makes it possible to obtain the space-time distributions of the main physical characteristics (temperatures of the ionic and electronic subsystems, density, pressure, etc.) in materials irradiated by high-energy proton beams and to analyze the formation and propagation of shock waves in them. The nonlinear differential equations describing the conservation laws of mass, energy, and momentum of electrons and ions in the Euler variables in the case of the propagation of shock waves has been solved with the Godunov scheme [S. K. Godunov, A.V. Zabrodin, M.Ya. Ivanov, A.N. Kraiko, and G.P. Prokopov, Numerical Solution of Multidimensional Problems in Gas Dynamics (Nauka, Moscow, 1976) [in Russian

  12. Hazards from High Intensity Lamps and Arcs

    NASA Technical Reports Server (NTRS)

    Sliney, D. H.

    1970-01-01

    The principal occupational health problem generally associated with high intensity arc lamps results from exposure of the eye and skin to ultraviolet radiation. Occasionally, the chorioretinal burns are of concern. The eye is generally more susceptible than the skin to injury from high intensity optical radiation sources whether ultraviolet, visible or infrared. Recent developments in technology have shown that some high intensity optical radiation sources which have output parameters greatly different from those encountered in the natural environment present a serious chorioretinal burn hazard.

  13. Survey of proposed high intensity accelerators and their applications

    SciTech Connect

    Schriber, S.O.

    1994-09-01

    Many interesting applications are being considered for high intensity accelerators. Implications of the technology developments that are enhancing these opportunities, or making them possible, will be covered in context of the applications. Applications include those for research (in areas such as material science, biological sciences, nuclear and high energy physics), accelerator-driven transmutation technologies, defense, and medicine. Specific examples will be used to demonstrate the impact that technology development can have and how transfer of this technology to industry can have an impact in the consumer and commercial arenas. Technology Development in rf power, controls, beam optics, rf structures, magnets, injectors, and beam halos will be considered.

  14. Prospects at high energies

    SciTech Connect

    Quigg, C.

    1988-11-01

    I discuss some possibilities for neutrino experiments in the fixed-target environment of the SPS, Tevatron, and UNK, with their primary proton beams of 0.4, 0.9, and 3.0 TeV. The emphasis is on unfinished business: issues that have been recognized for some time, but not yet resolved. Then I turn to prospects for proton-proton colliders to explore the 1-TeV scale. I review the motivation for new physics in the neighborhood of 1 TeV and mention some discovery possibilities for high-energy, high-luminosity hadron colliders and the implications they would have for neutrino physics. I raise the possibility of the direct study of neutrino interactions in hadron colliders. I close with a report on the status of the SSC project. 38 refs., 17 figs.

  15. High Intensity Radiated Fields (HIRF) project plan

    NASA Astrophysics Data System (ADS)

    Glynn, Michael S.; Blair, Jerry T.; Hintze, M. Marx

    1991-09-01

    Addressed here is the Federal Aviation Administration's approach to High Intensity Radiated Fields (HIRF) affecting the aviation community. Near- and far-term tasks are described. Deliverables, program management, scheduling, and cost issues are discussed.

  16. H- Ion Sources for High Intensity Proton Drivers

    SciTech Connect

    Johnson, Rolland Paul; Dudnikov, Vadim

    2015-02-20

    Existing RF Surface Plasma Sources (SPS) for accelerators have specific efficiencies for H+ and H- ion generation around 3 to 5 mA/cm2 per kW, where about 50 kW of RF power is typically needed for 50 mA beam current production. The Saddle Antenna (SA) SPS described here was developed to improve H- ion production efficiency, reliability and availability for pulsed operation as used in the ORNL Spallation Neutron Source . At low RF power, the efficiency of positive ion generation in the plasma has been improved to 200 mA/cm2 per kW of RF power at 13.56 MHz. Initial cesiation of the SPS was performed by heating cesium chromate cartridges by discharge as was done in the very first versions of the SPS. A small oven to decompose cesium compounds and alloys was developed and tested. After cesiation, the current of negative ions to the collector was increased from 1 mA to 10 mA with RF power 1.5 kW in the plasma (6 mm diameter emission aperture) and up to 30 mA with 4 kW RF power in the plasma and 250 Gauss longitudinal magnetic field. The ratio of electron current to negative ion current was improved from 30 to 2. Stable generation of H- beam without intensity degradation was demonstrated in the aluminum nitride (AlN) discharge chamber for 32 days at high discharge power in an RF SPS with an external antenna. Some modifications were made to improve the cooling and cesiation stability. The extracted collector current can be increased significantly by optimizing the longitudinal magnetic field in the discharge chamber. While this project demonstrated the advantages of the pulsed version of the SA RF SPS as an upgrade to the ORNL Spallation Neutron Source, it led to a possibility for upgrades to CW machines like the many cyclotrons used for commercial applications. Four appendices contain important details of the work carried out under this grant.

  17. High intensity proton acceleration at the Brookhaven AGS -- An update

    SciTech Connect

    Ahrens, L.; Alessi, J.; Blaskiewicz, M.

    1997-07-01

    The AGS accelerator complex is into its third year of 60+ {times} 10{sup 12} (teraproton = Tp) per cycle operation. The hardware making up the complex as configured in 1997 is briefly mentioned. The present level of accelerator performance is discussed. This includes beam transfer efficiencies at each step in the acceleration process, i.e. losses; which are a serious issue at this intensity level. Progress made in understanding beam behavior at the Linac-to-Booster (LtB) injection, at the Booster-to-AGS (BtA) transfer as well as across the 450 ms AGS accumulation porch is presented. The state of transition crossing, with the gamma-tr jump is described. Coherent effects including those driven by space charge are important at all of these steps.

  18. Dynamics of high-energy protons in the inner radiation belt during the 24th solar cycle on the data of the ARINA and VSPLESK low-orbit experiments.

    NASA Astrophysics Data System (ADS)

    Aleksandrin, Sergey; Mayorova, Marina; Koldashov, Sergey; Galper, Arkady; Zharaspayev, Temir

    2016-07-01

    Results of analysis of the inner radiation belt proton fluxes obtained in ARINA and VSPLESK satellite experiments are presented in this report The ARINA experiment is carried out on board the Russian low-orbit spacecraft Resurs-DK1 (altitude ˜600 km, inclination 70°, since 2006 till 2016). The VSPLESK experiment was fulfilled on board the International Space Station (altitude ~400 km, inclination 52°, since 2008 till 2013). The instruments register high-energy electrons and protons with energy range 3-30 MeV for electrons and 30-100 MeV for protons. The spectrometers allow measuring the particle energy with resolution 10% and angular resolution 7°. In this work the distribution of proton flux in the inner radiation belt (1.15proton intensity depends on the solar cycle phase (the minimum intensity value is in the solar maximum and vice versa) and varies 2-7 times for different L-shells.

  19. Future of high energy physics

    SciTech Connect

    Panofsky, W.K.H.

    1984-06-01

    A rough overview is given of the expectations for the extension of high energy colliders and accelerators into the xtremely high energy range. It appears likely that the SSC or something like it will be the last gasp of the conventional method of producing high energy proton-proton collisions using synchrotron rings with superconducting magnets. It is likely that LEP will be the highest energy e+e/sup -/ colliding beam storage ring built. The future beyond that depends on the successful demonstrations of new technologies. The linear collider offers hope in this respect for some extension in energy for electrons, and maybe even for protons, but is too early to judge whether, by how much, or when such an extension will indeed take place.

  20. Rapidly pulsed, high intensity, incoherent light source

    NASA Technical Reports Server (NTRS)

    Evans, J. C., Jr.; Brandhorst, H. W., Jr. (Inventor)

    1974-01-01

    A rapid pulsing, high intensity, incoherent light is produced by selectively energizing a plurality of discharge lamps with a triggering circuit. Each lamp is connected to a capacitor, and a power supply is electrically connected to all but one of the capacitors. This last named capacitor is electrically connected to a discharge lamp which is connected to the triggering circuit.

  1. Characterizing Hot Electron Generation and Transport via Bremsstrahlung Emission on the High Intensity OMEGA EP Laser

    NASA Astrophysics Data System (ADS)

    Peebles, J.; McGuffey, C.; Krauland, C.; Sorokovikova, A.; Qiao, B.; Krasheninnikov, S.; Beg, F. N.; Wei, M. S.; Stephens, R. B.; Chen, C. D.; Westover, B.; McLean, H. S.

    2014-10-01

    The investigation of high intensity laser generated fast electron beams is important for a number of High Energy Density Science applications, which include proton sources and fast ignition among others. A series of experimental campaigns performed using the kilojoule, 10-ps OMEGA EP laser closely examined the impact of a preformed plasma on laser plasma interaction and electron generation. Here we present the analysis of the measured bremsstrahlung x-ray radiation and the inferred results on fast electron characteristics. Simulations, performed with the Monte-Carlo code package ITS 3.0, generate the x-ray response of the target to an injected electron beam with a given temperature, energy and divergence angle. The simulated x-rays are then compared to those collected by the bremsstrahlung spectrometers, which allows us to characterize fast electrons created in the experiment. Preliminary results show a decrease in hot electron temperature with an increase in pre-pulse, which is further corroborated by magnetic electron and Cu-K α spectrometers. This work performed under the auspices of the US DOE under contracts DE-FOA-0000583 (FES, NNSA), DE-NA0002026 (NLUF) and DE-FC02-04ER54789 (FSC).

  2. Attenuation of ambient dose equivalent from neutrons by thick concrete, cast iron and composite shields for high energy proton, 3He, 48Ca and 238U ions on Cu targets for shielding design

    NASA Astrophysics Data System (ADS)

    Iwamoto, Yosuke; Ronningen, R. M.

    2011-02-01

    Data on neutron dose attenuation by thick concrete, cast iron, and cast iron plus concrete composite shields for heavy ions and protons having high energies (200-1000 MeV/u) are necessary for shielding designs of high-powered heavy ion accelerator facilities. Neutron production source terms, shield material attenuation lengths, and neutron dose rate reduction effectiveness of the bulk shielding in the angular range from 0° to 125° were determined by the Particle and Heavy Ion Transport Code (PHITS) for beams of 300 and 550 MeV/u 48Ca ions, 200 and 400 MeV/u 238U ions, 800 MeV/u 3He and 1 GeV protons. Calculated results of interaction lengths of concrete and cast iron were also compared with similar work performed by Agosteo et al., and to experimental and other calculated data on interaction lengths. The agreement can be regarded as acceptable.

  3. Ultra-high intensity laser plasma interactions

    NASA Astrophysics Data System (ADS)

    Langdon, A. Bruce; Hinkel, D. E.; Lasinski, Barbara F.; Still, C. H.

    1997-11-01

    In current studies of plasma interactions relevant to the fast ignitor concept,footnote M. Tabak, et al., Phys. Plasmas 1, 1626 (1994). an ultra-high intensity beam propagates through underdense, relativistically transparent, and then near solid density plasmas to create a channel. The ultra-high intensity beam propagates through this channel toward the compressed core where it creates hot electrons as it is absorbed. Three-dimensional fluid simulation(R. L. Berger et al), Phys. Fluids B, 2243 (1993). (with relativistic enhancements) studies of self-focusing in the underdense plasma will be reported and compared to PIC simulations in the same parameter regime. Beam structure near focus detracts from channel formation. Modeling in support of upcoming 100TW will be presented.

  4. Positron microanalysis with high intensity beams

    SciTech Connect

    Hulett, L.D. Jr.; Donohue, D.L.

    1990-01-01

    One of the more common applications for a high intensity slow positron facility will be microanalysis of solid materials. In the first section of this paper some examples are given of procedures that can be developed. Since most of the attendees of this workshop are experts in positron spectroscopy, comprehensive descriptions will be omitted. With the exception of positron emission microscopy, most of the procedures will be based on those already in common use with broad beams. The utility of the methods have all been demonstrated, but material scientists use very few of them because positron microbeams are not generally available. A high intensity positron facility will make microbeams easier to obtain and partially alleviate this situation. All microanalysis techniques listed below will have a common requirement, which is the ability to locate the microscopic detail or area of interest and to focus the positron beam exclusively on it. The last section of this paper is a suggestion of how a high intensity positron facility might be designed so as to have this capability built in. The method will involve locating the specimen by scanning it with the microbeam of positrons and inducing a secondary electron image that will immediately reveal whether or not the positron beam is striking the proper portion of the specimen. This scanning positron microscope' will be a somewhat prosaic analog of the conventional SEM. It will, however, be an indispensable utility that will enhance the practicality of positron microanalysis techniques. 6 refs., 1 fig.

  5. High Intensity Particle Physics at PW-class laser facilities

    NASA Astrophysics Data System (ADS)

    Bulanov, Stepan; Schroeder, Carl; Esarey, Eric; Esirkepov, Timur; Kando, Masaki; Rosanov, Nikolay; Korn, Georg; Bulanov, Sergey V.; Leemans, Wim P.

    2015-11-01

    The processes typical for high intensity particle physics, i.e., the interactions of charged particles with strong electromagnetic fields, have attracted considerable interest recently. Some of these processes, previously believed to be of theoretical interest only, are now becoming experimentally accessible. High intensity electromagnetic (EM) fields significantly modify the interactions of particles and EM fields, giving rise to the phenomena that are not encountered either in classical or perturbative quantum theory of these interactions. One of such phenomena is the radiation reaction, which radically influences the electron motion in an electromagnetic standing wave formed by two super-intense counter-propagating laser pulses. Depending on the laser intensity and wavelength, either classical or quantum mode of radiation reaction prevail, or both are strong. When radiation reaction dominates, electron motion evolves to limit cycles and strange attractors. This creates a new framework for high energy physics experiments on an interaction of energetic charged particle beams and colliding super-intense laser pulses. Work supported by U.S. DOE under Contract No. DE-AC02-05CH11231.

  6. FSU High Energy Physics

    SciTech Connect

    Prosper, Harrison B.; Adams, Todd; Askew, Andrew; Berg, Bernd; Blessing, Susan K.; Okui, Takemichi; Owens, Joseph F.; Reina, Laura; Wahl, Horst D.

    2014-12-01

    The High Energy Physics group at Florida State University (FSU), which was established in 1958, is engaged in the study of the fundamental constituents of matter and the laws by which they interact. The group comprises theoretical and experimental physicists, who sometimes collaborate on projects of mutual interest. The report highlights the main recent achievements of the group. Significant, recent, achievements of the group’s theoretical physicists include progress in making precise predictions in the theory of the Higgs boson and its associated processes, and in the theoretical understanding of mathematical quantities called parton distribution functions that are related to the structure of composite particles such as the proton. These functions are needed to compare data from particle collisions, such as the proton-proton collisions at the CERN Large Hadron Collider (LHC), with theoretical predictions. The report also describes the progress in providing analogous functions for heavy nuclei, which find application in neutrino physics. The report highlights progress in understanding quantum field theory on a lattice of points in space and time (an area of study called lattice field theory), the progress in constructing several theories of potential new physics that can be tested at the LHC, and interesting new ideas in the theory of the inflationary expansion of the very early universe. The focus of the experimental physicists is the Compact Muon Solenoid (CMS) experiment at CERN. The report, however, also includes results from the D0 experiment at Fermilab to which the group made numerous contributions over a period of many years. The experimental group is particularly interested in looking for new physics at the LHC that may provide the necessary insight to extend the standard model (SM) of particle physics. Indeed, the search for new physics is the primary task of contemporary particle physics, one motivated by the need to explain certain facts, such as the

  7. Fermilab main injector: High intensity operation and beam loss control

    NASA Astrophysics Data System (ADS)

    Brown, Bruce C.; Adamson, Philip; Capista, David; Chou, Weiren; Kourbanis, Ioanis; Morris, Denton K.; Seiya, Kiyomi; Wu, Guan Hong; Yang, Ming-Jen

    2013-07-01

    From 2005 through 2012, the Fermilab Main Injector provided intense beams of 120 GeV protons to produce neutrino beams and antiprotons. Hardware improvements in conjunction with improved diagnostics allowed the system to reach sustained operation at 400 kW beam power. Transmission was very high except for beam lost at or near the 8 GeV injection energy where 95% beam transmission results in about 1.5 kW of beam loss. By minimizing and localizing loss, residual radiation levels fell while beam power was doubled. Lost beam was directed to either the collimation system or to the beam abort. Critical apertures were increased while improved instrumentation allowed optimal use of available apertures. We will summarize the improvements required to achieve high intensity, the impact of various loss control tools and the status and trends in residual radiation in the Main Injector.

  8. High-intensity cyclotron for the IsoDAR experiment

    NASA Astrophysics Data System (ADS)

    Campo, D.; IsoDAR Collaboration

    2015-03-01

    The IsoDAR experiment is the MIT proposal to investigate about several neutrino properties, in order to explain some anomalies experimentally observed. It requires 10mA of proton beam at the energy of 60MeV to produce a high-intensity electron antineutrino flux from the production and the decay of 8Li: it is an ambitious goal for the accelerator design, due also to the fact that the machine has to be placed near a neutrino detector, like KAMLAND or WATCHMAN, located in underground sites. A compact cyclotron able to accelerate H2+ molecule beam up to energy of 60MeV/amu is under study. The critical issues of this machine concern the beam injection due to the effects of space charge, the efficiency of the beam extraction and the technical solutions needed to the machine assembly. Here, the innovative solutions and the preliminary results achieved by the IsoDAR team are discussed.

  9. Advanced modeling of high intensity accelerators

    SciTech Connect

    Ryne, R.D.; Habib, S.; Wangler, T.P.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to develop a new capability, based on high performance (parallel) computers, to perform large scale simulations of high intensity accelerators; (2) to apply this capability to modeling high intensity accelerators under design at LANL; and (3) to use this new capability to improve the understanding of the physics of intense charge particle beams, especially in regard to the issue of beam halo formation. All of these goals were met. In particular, the authors introduced split-operator methods as a powerful and efficient means to simulate intense beams in the presence of rapidly varying accelerating and focusing fields. They then applied these methods to develop scaleable, parallel beam dynamics codes for modeling intense beams in linacs, and in the process they implemented a new three-dimensional space charge algorithm. They also used the codes to study a number of beam dynamics issues related to the Accelerator Production of Tritium (APT) project, and in the process performed the largest simulations to date for any accelerator design project. Finally, they used the new modeling capability to provide direction and validation to beam physics studies, helping to identify beam mismatch as a major source of halo formation in high intensity accelerators. This LDRD project ultimately benefited not only LANL but also the US accelerator community since, by promoting expertise in high performance computing and advancing the state-of-the-art in accelerator simulation, its accomplishments helped lead to approval of a new DOE Grand Challenge in Computational Accelerator Physics.

  10. HIGH ENERGY PHYSICS POTENTIAL AT MUON COLLIDERS

    SciTech Connect

    PARSA,Z.

    2000-04-07

    In this paper, high energy physics possibilities and future colliders are discussed. The {mu}{sup +} {mu}{sup {minus}} collider and experiments with high intensity muon beams as the stepping phase towards building Higher Energy Muon Colliders (HEMC) are briefly reviewed and encouraged.