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Sample records for gev proton beam

  1. Aspects of strangeness production with 15 -- 30 GeV proton beams

    SciTech Connect

    Dover, C.B.

    1992-04-01

    We discuss the spectrum of physics questions related to strangeness which could be addressed with a 15--30 GeV proton storage ring. We focus on various aspects of strangeness production, including hyperon production in pp collisions, studies of hyperon-nucleon scattering, production of hyper-fragments in p-nucleus collisions, and hyperon spin observables in inclusive production.

  2. Preliminary consideration of a double, 480 GeV, fast cycling proton accelerator for production of neutrino beams at Fermilab

    SciTech Connect

    Piekarz, Henryk; Hays, Steven; /Fermilab

    2007-03-01

    We propose to build the DSF-MR (Double Super-Ferric Main Ring), 480 GeV, fast-cycling (2 second repetition rate) two-beam proton accelerator in the Main Ring tunnel of Fermilab. This accelerator design is based on the super-ferric magnet technology developed for the VLHC, and extended recently to the proposed LER injector for the LHC and fast cycling SF-SPS at CERN. The DSF-MR accelerator system will constitute the final stage of the proton source enabling production of two neutrino beams separated by 2 second time period. These beams will be sent alternately to two detectors located at {approx} 3000 km and {approx} 7500 km away from Fermilab. It is expected that combination of the results from these experiments will offer more than 3 order of magnitudes increased sensitivity for detection and measurement of neutrino oscillations with respect to expectations in any current experiment, and thus may truly enable opening the window into the physics beyond the Standard Model. We examine potential sites for the long baseline neutrino detectors accepting beams from Fermilab. The current injection system consisting of 400 MeV Linac, 8 GeV Booster and the Main Injector can be used to accelerate protons to 45 GeV before transferring them to the DSF-MR. The implementation of the DSF-MR will allow for an 8-fold increase in beam power on the neutrino production target. In this note we outline the proposed new arrangement of the Fermilab accelerator complex. We also briefly describe the DSF-MR magnet design and its power supply, and discuss necessary upgrade of the Tevatron RF system for the use with the DSF-MR accelerator. Finally, we outline the required R&D, cost estimate and possible timeline for the implementation of the DSF-MR accelerator.

  3. Induced radioactivity and its relation to beam losses in the CERN 26 GeV proton synchrotron

    NASA Astrophysics Data System (ADS)

    Sullivan, A. H.

    1987-06-01

    The results of induced radioactivity measurements made over the past 10 years around the CERN 26 GeV proton synchrotron are presented. The dose rate near different sections of the machine is shown to vary by factors up to 10 above and below the mean. A correlation is made between beam losses and radiation level, where it is estimated that to a first approximation in a machine that has been running a few years, the dose rate at 50 cm from a straight section between magnets and 24 h after stop will be 1.0 mSv/h (100 mrem/h) for beam losses equivalent to 1 W per meter of machine circumference. The dose rate after a cooling time of t days ( t ≪ 1 yr) is derived to be: D=p(1-0.4 log10t) mSv/h, where p is the average beam power loss, in W per m of circumference, over the two preceding months. This dependence of dose rate on decay time is compared with measured data from the PS for up to 43 days of cooling time. Beam losses estimated from induced activity dose rates using the above relation are shown to correspond reasonably with those expected for two operating conditions of the CERN 26 GeV proton synchrotron.

  4. Evaluation of the 3-GeV proton beam profile at the spallation target of the JSNS

    NASA Astrophysics Data System (ADS)

    Meigo, Shin-ichiro; Noda, Fumiaki; Ishikura, Syuichi; Futakawa, Masatoshi; Sakamoto, Shinichi; Ikeda, Yujiro

    2006-06-01

    At JSNS, 3-GeV protons beam is delivered from rapid cycling synchrotron (RCS) to the spallation neutron target. In order to reduce the damage of pitting on the target container, the peak current density should be kept as small as possible. In this study, the beam profile at spallation neutron target is evaluated. The phase-space distribution, including the space-charge effect, is calculated with SIMPSONS code. The beam profile on the target is obtained with the transfer matrix from exit of RCS to the target. As for injection to RCS, two methods of correlated and anti-correlated painting are considered. By using anti-correlated painting for injection of beam at RCS, it is found the shape of beam becomes flatter than the distribution by using correlated painting. As other aspect for the study of target, in order to carry out target performance test especially for the study of pitting issue, it is better to have the beam profile variety from the beginning of facility. The adjustable range for the beam profile at the beginning is also studied. Although the beam shape is narrow and the duty is very low, the strong enough peak density is achievable equivalent as 1 MW.

  5. INTERACTION OF A 24 GEV PROTON BEAM IWHT A MUON COLLIDER MERCURY JET TARGET EXPERIMENTAL RESULTS AND THERMODYNAMIC ASSESSMENT.

    SciTech Connect

    SIMOS,N.; KIRK,H.; FINFROCK,C.; GREENE,G.; LUDEWIG,H.; MCDONALD,K.; MOKHOV,N.

    2001-11-11

    A muon collider or a neutrino factory based on a muon storage ring require intense beams of muons that can be generated by a 1-4 MW proton beam incident on a moving target inside a 20-T solenoid magnet, with a mercury jet as a preferred example. This paper addresses the thermodynamic interaction of the intense proton beam with the proposed mercury jet target, and the consequences of the generated pressure waves on the target integrity. Specifically, a 24 GeV proton beam with approximately 16 TP (1 TP = 10{sup 12} protons) per pulse and a pulse length of 2 ns will interact with a 1 cm diameter mercury jet within the 20-Tesla magnetic field. In one option, a train of six such proton pulses is to be delivered on target within 2 {micro}s, in which case the state of the mercury jet following the interaction with each pulse is critical. Using the equation of state for mercury from the SESAME library, in combination with the energy deposition rates calculated the by the hadron interaction code MARS, the induced 3-D pressure field in the target is estimated. The consequent pressure wave propagation and attenuation in the mercury jet is calculated using a transient analysis based on finite element modeling, and the state of the mercury jet at the time of arrival of the subsequent pulse is assessed. Issues associated with the use of a liquid metal jet as a target candidate are addressed. Lastly, some experimental results from the BNL E951 experiment are presented and discussed.

  6. ACCELERATING POLARIZED PROTONS TO 250 GEV

    SciTech Connect

    BAI,M.; AHRENS, L.; ALEKSEEV, I.G.; ALESSI, J.; BEEBE-WANG, J.; ET AL.

    2007-06-25

    The Relativistic Heavy Ion Collider (RHIC) as the first high energy polarized proton collider was designed t o provide polarized proton collisions a t a maximum beam energy of 250 GeV. I t has been providing collisions a t a beam energy of 100 Gel' since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during the acceleration from injection to 100 GeV with careful control of the betatron tunes and the vertical orbit distortions. However, the intrinsic spin resonances beyond 100 GeV are about a factor of two stronger than those below 100 GeV? making it important t o examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were accelerated t o the record energy of 250 GeV in RHIC with a polarization of 46% measured a t top energy in 2006. The polarization measurement as a function of beam energy also shows some polarization loss around 136 GeV, the first strong intrinsic resonance above 100 GeV. This paper presents the results and discusses the sensitivity of the polarization survival t o orbit distortions.

  7. Polarized proton beams in RHIC

    SciTech Connect

    Zelenski, A.

    2010-10-04

    The polarized beam for RHIC is produced in the optically-pumped polarized H{sup -} ion source and then accelerated in Linac to 200 MeV for strip-injection to Booster and further accelerated 24.3 GeV in AGS for injection in RHIC. In 2009 Run polarized protons was successfully accelerated to 250 GeV beam energy. The beam polarization of about 60% at 100 GeV beam energy and 36-42% at 250 GeV beam energy was measured with the H-jet and p-Carbon CNI polarimeters. The gluon contribution to the proton spin was studied in collisions of longitudinally polarized proton beams at 100 x 100 GeV. At 250 x 250 GeV an intermediate boson W production with the longitudinally polarized beams was studied for the first time.

  8. Beam Transport of 4 GeV Protons from AGS to the Proton Interrogation Target of the Neutrino Line (Z_line) and Effect of the Air on the Transported Beam

    SciTech Connect

    Tsoupas,N.; Ahrens, L.; Pile, P.; Thieberger, P.; Murray, M.M.

    2008-10-01

    As part of the preparation for the Proton Interrogation Experiment, we have calculated the beam optics for the transport of 4 GeV protons, from the AGS extraction point, to the 'Cross-Section Target Wheel 1' and to the 'Proton Interrogation Target'. In this technical note we present three possible beam-transports each corresponding to a particular Fast Extracted Beam W B setup of the AGS. In addition we present results on the effect of the atmospheric air, (which fills the drift space of the last 100 [m] of the transport line), on the size of the beam, at two locations along the drift space, one location at the middle of the drift space and the other at the end where the 'Proton Interrogation Target' is placed. All the beam transports mentioned above require the removal of the WD1 dipole magnet, which is the first magnet of the W-line, because it acts as a limiting beam aperture, and the magnet is not used in the beam transport. An alternative solution of a beam transport, which does not require the removal of the WD1 magnet, is also presented. In this solution, which models the transport line using the TURTLE computer code[7], the vertical beam sizes at the location of the WD1 magnet is minimized to allow 'lossless' beam transport at the location of the WD1 magnet. A similar solution, but using a MAD model of the line, is also presented.

  9. THERMAL SHOCK INDUCED BY A 24 GEV PROTON BEAM IN THE TEST WINDOWS OF THE MUON COLLIDER EXPERIMENT E951 - TEST RESULTS AND THEORETICAL PREDICTIONS.

    SciTech Connect

    SIMOS,N.; KIRK,H.; FINFROCK,C.; PRIGL,R.; BROWN,K.; KAHN,S.; LUDEWIG,H.; MCDONALDK.; CATES,M.; TSAI,J.; BESHEARS,D.; RIEMER,B.

    2001-11-11

    The need for intense muon beams for muon colliders and neutrino factories has lead to a concept of a high performance target station in which a 1-4 MW proton beam of 6-24 GeV impinges on a target inside a high field solenoid channel. While novel technical issues exist regarding the survivability of the target itself, the need to pass the tightly focused proton beam through beam windows poses additional concerns. In this paper, issues associated with the interaction of a proton beam with window structures designed for the muon targetry experiment E951 at BNL are explored. Specifically, a 24 GeV proton beam up to 16 x 10{sup 12} per pulse and a pulse length of approximately 100 ns is expected to be tightly focused (to 0.5 mm rms one sigma radius) on an experimental target. Such beam will induce very high thermal, quasi-static and shock stresses in the window structure that exceed the strength of most common materials. In this effort, a detailed assessment of the thermal/shock response of beam windows is attempted with a goal of identifying the best window material candidate. Further, experimental strain results and comparison with the predicted values are presented and discussed.

  10. The Ignition of Cylindrical Fusion Targets by Multi-Mega-Ampere GeV Proton Beams below the Alfvén Limit

    NASA Astrophysics Data System (ADS)

    Winterberg, Friedwardt

    2014-11-01

    It is shown that cylindrical deuterium targets can be ignited with multi-mega-ampere GeV proton beams below the Alfvén limit and a small amount of tritium. The proton beams can be generated by discharging a magnetically insulated gigavolt capacitor. Surrounding the thermonuclear microexplosion with a thick layer of liquid hydrogen, heated to a ~ 105 K plasma by the thermalization of the fusion reaction neutrons, most of the energy released can be converted into electric energy by a magnetohydrodynamic generator.

  11. Analysis of 440 GeV proton beam-matter interaction experiments at the High Radiation Materials test facility at CERN

    NASA Astrophysics Data System (ADS)

    Burkart, F.; Schmidt, R.; Raginel, V.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.

    2015-08-01

    In a previous paper [Schmidt et al., Phys. Plasmas 21, 080701 (2014)], we presented the first results on beam-matter interaction experiments that were carried out at the High Radiation Materials test facility at CERN. In these experiments, extended cylindrical targets of solid copper were irradiated with beam of 440 GeV protons delivered by the Super Proton Synchrotron (SPS). The beam comprised of a large number of high intensity proton bunches, each bunch having a length of 0.5 ns with a 50 ns gap between two neighboring bunches, while the length of this entire bunch train was about 7 μs. These experiments established the existence of the hydrodynamic tunneling phenomenon the first time. Detailed numerical simulations of these experiments were also carried out which were reported in detail in another paper [Tahir et al., Phys. Rev. E 90, 063112 (2014)]. Excellent agreement was found between the experimental measurements and the simulation results that validate our previous simulations done using the Large Hadron Collider (LHC) beam of 7 TeV protons [Tahir et al., Phys. Rev. Spec. Top.--Accel. Beams 15, 051003 (2012)]. According to these simulations, the range of the full LHC proton beam and the hadronic shower can be increased by more than an order of magnitude due to the hydrodynamic tunneling, compared to that of a single proton. This effect is of considerable importance for the design of machine protection system for hadron accelerators such as SPS, LHC, and Future Circular Collider. Recently, using metal cutting technology, the targets used in these experiments have been dissected into finer pieces for visual and microscopic inspection in order to establish the precise penetration depth of the protons and the corresponding hadronic shower. This, we believe will be helpful in studying the very important phenomenon of hydrodynamic tunneling in a more quantitative manner. The details of this experimental work together with a comparison with the numerical

  12. Collimated GeV proton beam generated by the interaction of ultra-intense laser with a uniform near-critical underdense plasma

    NASA Astrophysics Data System (ADS)

    Gu, Y. J.; Zhu, Z.; Li, Y. Y.; Li, X. F.; Chen, C. Y.; Kong, Q.; Kawata, S.

    2011-08-01

    An ultra-intense short-pulsed laser interacting with a uniform underdense plasma with near-critical density is investigated by 2.5-dimensional particle-in-cell simulations. It is found that a collimated proton beam with maximum energy up to the GeV was generated. The corresponding proton acceleration mechanism is analyzed. The laser wakefield acceleration (LWFA) electrons play an important role as a driving beam. Due to the features of LWFA electrons, quasi-monoenergetic distribution and good collimation, the protons can be accelerated for a long distance by the charge-separated electric field. The proton beam in this regime is also well collimated and the amount can reach several nC. Moreover, it is found that the LWFA electrons can overtake the laser and stand quasi-synchronized in the center of pulse. Therefore the electrons can absorb energy from the laser and transfer it to the protons like in the break-out afterburner (BOA) scheme in laser irradiated on ultra-thin film target.

  13. Proton-proton colliding beam facility ISABELLE

    SciTech Connect

    Hahn, H

    1980-01-01

    This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed.

  14. RHIC 100 GeV Polarized Proton Luminosity

    SciTech Connect

    Zhang, S. Y.

    2014-01-17

    A big problem in RHIC 100 GeV proton run 2009 was the significantly lower luminosity lifetime than all previous runs. It is shown in this note that the beam intensity decay in run 2009 is caused by the RF voltage ramping in store. It is also shown that the beam decay is not clearly related to the beam momentum spread, therefore, not directly due to the 0.7m. β* Furthermore, the most important factor regarding the low luminosity lifetime is the faster transverse emittance growth in store, which is also much worse than the previous runs, and is also related to the RF ramping. In 100 GeV proton run 2012a, the RF ramping was abandoned, but the β* was increased to 0.85m, with more than 20% loss of luminosity, which is not necessary. It is strongly suggested to use smaller β* in 100 GeV polarized proton run 2015/2016

  15. Radiation shielding of the beam absorber in the MI 8-GeV beam line

    SciTech Connect

    Rakhno, I.; /Fermilab

    2006-01-01

    Results of Monte Carlo radiation shielding calculations performed for the beam absorber of the MI 8 GeV beam line are presented and discussed. The possibility to reach the level of 10{sup 19} protons per year is investigated.

  16. Polarized proton collisions at 205 GeV at RHIC.

    PubMed

    Bai, M; Roser, T; Ahrens, L; Alekseev, I G; Alessi, J; Beebe-Wang, J; Blaskiewicz, M; Bravar, A; Brennan, J M; Bruno, D; Bunce, G; Courant, E; Drees, A; Fischer, W; Gardner, C; Gill, R; Glenn, J; Haeberli, W; Huang, H; Jinnouchi, O; Kewisch, J; Luccio, A; Luo, Y; Nakagawa, I; Okada, H; Pilat, F; Mackay, W W; Makdisi, Y; Montag, C; Ptitsyn, V; Satogata, T; Stephenson, E; Svirida, D; Tepikian, S; Trbojevic, D; Tsoupas, N; Wise, T; Zelenski, A; Zeno, K; Zhang, S Y

    2006-05-01

    The Brookhaven Relativistic Heavy Ion Collider (RHIC) has been providing collisions of polarized protons at a beam energy of 100 GeV since 2001. Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the intrinsic spin resonances beyond 100 GeV are about a factor of 2 stronger than those below 100 GeV making it important to examine the impact of these strong intrinsic spin resonances on polarization survival and the tolerance for vertical orbit distortions. Polarized protons were first accelerated to the record energy of 205 GeV in RHIC with a significant polarization measured at top energy in 2005. This Letter presents the results and discusses the sensitivity of the polarization survival to orbit distortions. PMID:16712305

  17. 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

  18. An 8-GeV Synchrotron-Based Proton Driver

    SciTech Connect

    Weiren Chou

    2003-06-04

    In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. Such a facility is a possible candidate for a construction project in the U.S. starting in the middle of this decade. The key technical element is a new machine, dubbed the ''Proton Driver,'' as a replacement of the present Booster. The study of an 8-GeV synchrotron-based proton driver has been completed and published. This paper will give a summary report, including machine layout and performance, optics, beam dynamics issues, technical systems design, civil construction, cost estimate and schedule.

  19. Self-Organizing GeV, Nanocoulomb, Collimated Proton Beam from Laser Foil Interaction at 7x10{sup 21} W/cm{sup 2}

    SciTech Connect

    Yan, X. Q.; Wu, H. C.; Meyer-ter-Vehn, J.; Sheng, Z. M.; Chen, J. E.

    2009-09-25

    We report on a self-organizing, quasistable regime of laser proton acceleration, producing 1 GeV nanocoulomb proton bunches from laser foil interaction at an intensity of 7x10{sup 21} W/cm{sup 2}. The results are obtained from 2D particle-in-cell simulations, using a circular polarized laser pulse with Gaussian transverse profile, normally incident on a planar, 500 nm thick hydrogen foil. While foil plasma driven in the wings of the driving pulse is dispersed, a stable central clump with 1-2lambda diameter is forming on the axis. The stabilization is related to laser light having passed the transparent parts of the foil in the wing region and enfolding the central clump that is still opaque. Varying laser parameters, it is shown that the results are stable within certain margins and can be obtained both for protons and heavier ions such as He{sup 2+}.

  20. Characteristic X-ray radiation excited by 450 MeV/nucleon C+6 ions and 1.3 GeV protons in extracted and circulated beams of accelerator U70

    NASA Astrophysics Data System (ADS)

    Afonin, A. G.; Britvich, G. I.; Chesnokov, Yu. A.; Durum, A. A.; Kostin, M. Yu.; Maisheev, V. A.; Pikalov, V. A.; Savin, D. A.; Yanovich, A. A.; Kubankin, A. S.; Nazhmudinov, R. M.; Shul'ga, N. F.; Uglov, S. R.; Shchagin, A. V.

    2015-07-01

    The results of the experimental observation of characteristic X-ray radiation (CXR) excited in solid targets by the extracted and circulated 450 MeV/u C+6 ions beams and circulating 1.3 GeV protons beam are presented. The spectra of X-ray radiation measured from different targets are presented and discussed. It was found that the background radiation near the beams is low enough that allows the observation of the CXR spectral peaks with energies from a few to tens keV by semiconductor X-ray detectors. Applications of the CXR for monitoring of the number of accelerated particles in experimental applied and basic research, including radiobiology and radiation medicine as well as the relativistic nuclear physics and steering of beams by bent crystalline deflectors are proposed.

  1. Proton beam therapy facility

    SciTech Connect

    Not Available

    1984-10-09

    It is proposed to build a regional outpatient medical clinic at the Fermi National Accelerator Laboratory (Fermilab), Batavia, Illinois, to exploit the unique therapeutic characteristics of high energy proton beams. The Fermilab location for a proton therapy facility (PTF) is being chosen for reasons ranging from lower total construction and operating costs and the availability of sophisticated technical support to a location with good access to patients from the Chicago area and from the entire nation. 9 refs., 4 figs., 26 tabs.

  2. RHIC polarized proton-proton operation at 100 GeV in Run 15

    SciTech Connect

    Schoefer, V.; Aschenauer, E. C.; Atoian, G.; Blaskiewicz, M.; Brown, K. A.; Bruno, D.; Connolly, R.; D Ottavio, T.; Drees, K. A.; Dutheil, Y.; Fischer, W.; Gardner, C.; Gu, X.; Hayes, T.; Huang, H.; Laster, J.; Liu, C.; Luo, Y.; Makdisi, Y.; Marr, G.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R.; Marusic, A.; Minty, M.; Montag, C.; Morris, J.; Narayan, G.; Nemesure, S.; Pile, P.; Poblaguev, A.; Ranjbar, V.; Robert-Demolaize, G.; Roser, T.; Schmidke, W. B.; Severino, F.; Shrey, T.; Smith, K.; Steski, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; White, S.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S. Y.

    2015-05-03

    The first part of RHIC Run 15 consisted of ten weeks of polarized proton on proton collisions at a beam energy of 100 GeV at two interaction points. In this paper we discuss several of the upgrades to the collider complex that allowed for improved performance. The largest effort consisted in commissioning of the electron lenses, one in each ring, which are designed to compensate one of the two beam-beam interactions experienced by the proton bunches. The e-lenses raise the per bunch intensity at which luminosity becomes beam-beam limited. A new lattice was designed to create the phase advances necessary for a beam-beam compensation with the e-lens, which also has an improved off-momentum dynamic aperture relative to previous runs. In order to take advantage of the new, higher intensity limit without suffering intensity driven emittance deterioration, other features were commissioned including a continuous transverse bunch-by-bunch damper in RHIC and a double harmonic RF cature scheme in the Booster. Other high intensity protections include improvements to the abort system and the installation of masks to intercept beam lost due to abort kicker pre-fires.

  3. Beam loss caused by edge focusing of injection bump magnets and its mitigation in the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex

    NASA Astrophysics Data System (ADS)

    Hotchi, H.; Tani, N.; Watanabe, Y.; Harada, H.; Kato, S.; Okabe, K.; Saha, P. K.; Tamura, F.; Yoshimoto, M.

    2016-01-01

    In the 3-GeV rapid cycling synchrotron of the Japan Proton Accelerator Research Complex, transverse injection painting is utilized not only to suppress space-charge induced beam loss in the low energy region but also to mitigate foil scattering beam loss during charge-exchange injection. The space-charge induced beam loss is well minimized by the combination of modest transverse painting and full longitudinal painting. But, for sufficiently mitigating the foil scattering part of beam loss, the transverse painting area has to be further expanded. However, such a wide-ranging transverse painting had not been realized until recently due to beta function beating caused by edge focusing of pulsed injection bump magnets during injection. This beta function beating additionally excites random betatron resonances through a distortion of the lattice superperiodicity, and its resultant deterioration of the betatron motion stability causes significant extra beam loss when expanding the transverse painting area. To solve this issue, we newly installed pulse-type quadrupole correctors to compensate the beta function beating. This paper presents recent experimental results on this correction scheme for suppressing the extra beam loss, while discussing the beam loss and its mitigation mechanisms with the corresponding numerical simulations.

  4. Energy Production Demonstrator for Megawatt Proton Beams

    SciTech Connect

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

    2014-07-16

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

  5. Radiation damage of heavy crystalline detector materials by 24 GeV protons

    NASA Astrophysics Data System (ADS)

    Barysevich, A.; Dormenev, V.; Fedorov, A.; Glaser, M.; Kobayashi, M.; Korjik, M.; Maas, F.; Mechinski, V.; Rusack, R.; Singovski, A.; Zoueyski, R.

    2013-02-01

    Samples of three heavy crystalline materials: PbWO4, Bi4Si3O12, and PbF2 were irradiated in a high-intensity 24 GeV proton beam at the CERN PS to fluencies of 3.8×1013 protons/cm2. The optical transmission radiation damage was measured and all crystals show a shift of the cutoff in the transmission spectrum that is not observed when the crystals are irradiated with γ radiation. This shift of the cutoff under proton irradiation seems to be a general property of the heavy crystalline materials. A mechanism for this proton-induced transmission damage is discussed.

  6. Neutron yields for reactions induced by 120 GeV protons on thick copper target

    SciTech Connect

    Kajimoto, Tsuyoshi; Sanami, Toshiya; Iwamoto, Yosuke; Shigyo, Nobuhiro; Hagiwara, Masayuki; Saitoh, Kiwamu; Nakashima, Hiroshi; Ishibashi, Kenji; Lee, Hee-Seock; Ramberg, Eric; Coleman, Richard; /Fermilab

    2011-02-01

    We developed an experimental method to measure neutron energy spectrum for 120-GeV protons on a thick copper target at Fermilab Test Beam Facility (FTBF). The spectrum in the energy range from 16 to 1600 MeV was obtained for 60-cm long copper target by time-of-flight technique with an NE213 scintillator and 5.5-m flight path. Energy spectra of neutrons generated from an interaction with beam and materials are important to design shielding structure of high energy accelerators. Until now, the energy spectra for the incident energy up to 3 GeV have been measured by several groups, Ishibashi et al., Amian et al., and Leray et al. In the energy region above 3 GeV, few experimental data are available because of small number of facilities for neutron experiment. On the other hand, concerning simulation codes, theoretical models for particle generation and transportation are switched from intermediate to high energy one around this energy. The spectra calculated by the codes have not been examined using experimental data. In shielding experiments using 120 GeV hadron beam, experimental data shows systematic differences from calculations. Hagiwara et al. have measured leakage neutron spectra behind iron and concrete shield from 120 GeV proton on target at anti-proton target station in Fermilab by using Bonner Spheres with unfolding technique. In CERN, Nakao et al reported experimental results of neutron spectra behind iron and concrete wall from 120 GeV/c proton and pion mixed beam on copper by using NE213 liquid scintillators with unfolding technique. Both of the results reported systematic discrepancies between experimental and calculation results. Therefore, experimental data are highly required to verify neutron production part of calculations. In this study, we developed an experimental method to measure neutron energy spectrum for 120 GeV proton on target. The neutron energy was determined using time-of-flight technique. We used the Fermilab Test Beam Facility (FTBF

  7. A 10-GeV, 5-MW proton source for a muon-muon collider

    SciTech Connect

    Cho, Y.; Chae, Y.; Crosbie, E.; Friedsam, H.; Harkay, K.; Horan, D.; Kustom, R.; Lessner, E.; McDowell, W.; McGhee, D.; Moe, H.; Nielsen, R.; Norek, G.; Peterson, K.; Qian, Y.; Thompson, K.; White, M.

    1996-05-01

    The performance parameters of a proton source which produces the required flux of muons for a 2-TeV on 2-TeV muon collider are: a beam energy of 10 GeV, a repetition rate of 30 Hz, two bunches per pulse with 5{times}10{sup 13} protons per bunch, and an rms bunch length of 3 nsec (1). Aside from the bunch length requirement, these parameters are identical to those of a 5-MW proton source for a spallation neutron source based on a 10-GeV rapid cycling synchrotron (RCS) (2). The 10-GeV synchrotron uses a 2-GeV accelerator system as its injector, and the 2-GeV RCS is an extension of a feasibility study for a 1-MW spallation source described elsewhere (3{endash}9). A study for the 5-MW spallation source was performed for ANL site-specific geometrical requirements. Details are presented for a site-independent proton source suitable for the muon collider utilizing the results of the 5-MW spallation source study. {copyright} {ital 1996 American Institute of Physics.}

  8. Polarized proton beam for eRHIC

    SciTech Connect

    Huang, H.; Meot, F.; Ptitsyn, V.; Roser, T.

    2015-05-03

    RHIC has provided polarized proton collisions from 31 GeV to 255 GeV in the past decade. To preserve polarization through numerous depolarizing resonances through the whole accelerator chain, harmonic orbit correction, partial snakes, horizontal tune jump system and full snakes have been used. In addition, close attentions have been paid to betatron tune control, orbit control and beam line alignment. The polarization of 60% at 255 GeV has been delivered to experiments with 1.8×1011 bunch intensity. For the eRHIC era, the beam brightness has to be maintained to reach the desired luminosity. Since we only have one hadron ring in the eRHIC era, existing spin rotator and snakes can be converted to six snake configuration for one hadron ring. With properly arranged six snakes, the polarization can be maintained at 70% at 250 GeV. This paper summarizes the effort and plan to reach high polarization with small emittance for eRHIC.

  9. Transverse Spin Asymmetries in the CNI Region of Elastic Proton-Proton Scattering at s=200 GeV

    NASA Astrophysics Data System (ADS)

    Svirida, Dmitry

    2016-02-01

    Precise measurements of transverse spin asymmetries in proton-proton elastic scattering at very small values of four-momentum transfer squared, t, have been performed using the Relativistic Heavy Ion Collider (RHIC) polarized proton beams. The measurements of both single and double spin asymmetries were made at the center-of-mass energy s = 200 GeV and in the region 0.003 ≤|t|≤ 0.035 (GeV/c)2, which was accessed using Roman Pot devices incorporated into the STAR experimental setup. The obtained set of asymmetries is sensitive to the poorly known hadronic contribution to the spin-flip amplitudes and provide significant constraints for the theoretical descriptions of the reaction mechanism of proton-proton elastic scattering at high energies.

  10. A CONCEPTUAL 3-GEV LANSCE LINAC UPGRADE FOR ENHANCED PROTON RADIOGRAPHY

    SciTech Connect

    Garnett, Robert W; Rybarcyk, Lawrence J.; Merrill, Frank E.; O'Hara, James F.; Rees, Daniel E.; Walstrom, Peter L.

    2012-05-14

    A conceptual design of a 3-GeV linac upgrade that would enable enhanced proton radiography at the Los Alamos Neutron Science Center (LANSCE) is presented. The upgrade is based on the use of superconducting accelerating cavities to increase the present LANSCE linac output energy from 800 MeV to 3 GeV. The LANSCE linac currently provides negative hydrogen ion (H{sup -}) and proton (H{sup +}) beams to several user facilities that support Isotope Production, NNSA Stockpile Stewardship, and Basic Energy Science programs. Required changes to the front-end, the accelerating structures, and to the RF systems to meet the new performance goals, and changes to the existing beam switchyard to maintain operations for a robust user program are also described.

  11. Proton beam monitor chamber calibration.

    PubMed

    Gomà, C; Lorentini, S; Meer, D; Safai, S

    2014-09-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences-of the order of 3%-were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth-i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers-rather than cylindrical chambers-for the reference dosimetry of pseudo-monoenergetic proton beams. PMID:25109620

  12. The NuMI proton beam at Fermilab successes and challenges

    SciTech Connect

    Childress, S.; /Fermilab

    2008-11-01

    The NuMI beam at Fermilab has delivered over 5 x 10{sup 20} 120 GeV protons to the neutrino production target since the start for MINOS [1] neutrino oscillation experiment operation in 2005. We report on proton beam commissioning and operation status, including successes and challenges with this beam.

  13. Beam halo in mismatched proton beams.

    SciTech Connect

    Wangler, Thomas P.,; Allen, C. K.; Chan, D.; Colestock, P. L. ,; Crandall, K. R.; Qiang, J.; Garnett, R. W.; Lysenko, W. P.; Gilpatrick, J. D.; Schneider, J. D.; Schulze, M. E.; Sheffield, R. L.; Smith, H. V.

    2002-01-01

    Progress was made during the past decade towards a better understanding of halo formation caused by beam mismatch in high-intensity beams. To test these ideas an experiment was carried out at Los Alamos with proton beams in a 52-quadrupole focusing channel. Rms emittances and beam widths were obtained from measured beam profiles for comparison with the maximum emittance growth predictions of a free-energy model and the maximum haloamplitude predictions of a particle-core model. The experimental results are also compared with multiparticle simulations. In this paper we will present the experimental results and discuss the implications with respect to the validity of both the models and the simulations. Keywords: beam halo, emittance growth, beam profiles, simulations, space charge, mismatch

  14. Charmed Meson Production in 800 GEV Proton-Proton Interactions.

    NASA Astrophysics Data System (ADS)

    Senko, Mark Frederick

    The purpose of this dissertation is to present the results of a study concerning the energy dependence of charmed meson production properties as a test of Quantum Chromodynamics (QCD). This experiment was performed at Fermi National Accelerator Laboratory, using a rapid cycling bubble chamber (LEBC) as a hydrogen target and high resolution vertex detector, in combination with the Fermilab Multiparticle Spectrometer (FMPS). The multiplicity trigger was unbiased, and spectrometer acceptance was good at x_ {F} >=q 0. A comparison of the results from previous experiments at center of mass energies sqrt{s} <=q 27 GeV and sqrt {s} >=q 53 GeV implies a total charm particle production cross section which rises rapidly as a function of sqrt{s} . The result of our experiment, sigma (D/| D) = 42.7 +/- 7.8 mub at sqrt{s} = 38 GeV, indicates a slower rise, in agreement with QCD predictions. A maximum likelihood fit to the parameterization of the differential cross section as d^2sigma/dx_{F}dp _sp{|}{2} ~ (1 - | x_{F }|)^{n}e^{-bp _sp{|}{2}} gives the results n = 8.4_sp {-1.9}{+2.2}, b = 0.78_sp{-0.16}{+0.19} (GeV/c)^{-2}, and < pbot > = 1.1_sp{-0.1}{+0.2} GeV/c. When compared with results from the lower energy experiments, these values indicate charm production becoming more central and < pbot > being consistent with the charmed quark mass. These results are once again consistent with QCD predictions. Lastly, analysis has shown that sigma(D ^*^+/-)/sigma(D^0) is governed primarily by spin statistics, displaying no energy dependence. The resulting cross section for D^*^+/- production is sigma(D^*^+/-) = 13.31 +/- 5.74 mub.

  15. BEAM HALO IN PROTON LINAC BEAMS

    SciTech Connect

    T. WANGLER; K. CRANDALL

    2000-08-01

    In this paper we review the present picture of km halo in proton linacs. Space-charge forces acting in mismatched beams have been identified as a major cause of beam-halo. We present a definition of halo based on a ratio of moments of the distribution of the beam coordinates. We find from our initial studies that for halo detined in this way, a beam can have rms emittance growth without halo growth, but halo growth is always accompanied by rms emittance growth. We describe the beam-halo experiment that is in preparation at Los Alamos, which will address questions about the beam profiles, maximum particle amplitudes, and rms emittance growth associated with the halo.

  16. Neutron energy spectrum from 120 GeV protons on a thick copper target

    SciTech Connect

    Shigyo, Nobuhiro; Sanami, Toshiya; Kajimoto, Tsuyoshi; Iwamoto, Yosuke; Hagiwara, Masayuki; Saito, Kiwamu; Ishibashi, Kenji; Nakashima, Hiroshi; Sakamoto, Yukio; Lee, Hee-Seock; Ramberg, Erik; /Fermilab

    2010-08-01

    Neutron energy spectrum from 120 GeV protons on a thick copper target was measured at the Meson Test Beam Facility (MTBF) at Fermi National Accelerator Laboratory. The data allows for evaluation of neutron production process implemented in theoretical simulation codes. It also helps exploring the reasons for some disagreement between calculation results and shielding benchmark data taken at high energy accelerator facilities, since it is evaluated separately from neutron transport. The experiment was carried out using a 120 GeV proton beam of 3E5 protons/spill. Since the spill duration was 4 seconds, protoninduced events were counted pulse by pulse. The intensity was maintained using diffusers and collimators installed in the beam line to MTBF. The protons hit a copper block target the size of which is 5cm x 5cm x 60 cm long. The neutrons produced in the target were measured using NE213 liquid scintillator detectors, placed about 5.5 m away from the target at 30{sup o} and 5 m 90{sup o} with respect to the proton beam axis. The neutron energy was determined by time-of-flight technique using timing difference between the NE213 and a plastic scintillator located just before the target. Neutron detection efficiency of NE213 was determined on basis of experimental data from the high energy neutron beam line at Los Alamos National Laboratory. The neutron spectrum was compared with the results of multiparticle transport codes to validate the implemented theoretical models. The apparatus would be applied to future measurements to obtain a systematic data set for secondary particle production on various target materials.

  17. 6-D weak-strong beam-beam simulation study of proton lifetime in presence of head-on beam-beam compensation in the RHIC

    SciTech Connect

    Luo, Y.; Fischer, W.

    2010-08-01

    In this note we summarize the calculated particle loss of a proton bunch in the presence of head-on beam-beam compensation in the Relativistic Heavy Ion Collider (RHIC). To compensate the head-on beam-beam effect in the RHIC 250 GeV polarized proton run, we are introducing a DC electron beam with the same transverse profile as the proton beam to collide with the proton beam. Such a device is called an electron lens (e-lens). In this note we first present the optics and beam parameters and the tracking setup. Then we calculate and compare the particle loss of a proton bunch with head-on beam-beam compensation, phase advance of k{pi} between IP8 and the center of the e-lens and second order chromaticity correction. We scanned the proton beam's linear chromaticity, working point and bunch intensity. We also scanned the electron beam's intensity, transverse beam size. The effect of the electron-proton transverse offset in the e-lens was studied. In the study 6-D weak-strong beam-beam interaction model a la Hirata is used for proton collisions at IP6 and IP8. The e-lens is modeled as 8 slices. Each slice is modeled with as drift - (4D beam-beam kick) - drift.

  18. An improved 8 GeV beam transport system for the Fermi National Accelerator Laboratory

    SciTech Connect

    Syphers, M.J.

    1987-06-01

    A new 8 GeV beam transport system between the Booster and Main Ring synchrotrons at the Fermi National Accelerator Laboratory is presented. The system was developed in an effort to improve the transverse phase space area occupied by the proton beam upon injection into the Main Ring accelerator. Problems with the original system are described and general methods of beamline design are formulated. Errors in the transverse properties of a beamline at the injection point of the second synchrotron and their effects on the region in transverse phase space occupied by a beam of particles are discussed. Results from the commissioning phase of the project are presented as well as measurements of the degree of phase space dilution generated by the transfer of 8 GeV protons from the Booster synchrotron to the Main Ring synchrotron.

  19. MARS14 simulation of Fermilab 120-GeV beam dumps

    SciTech Connect

    Nikolai V. Mokhov

    2003-04-09

    To estimate groundwater activation around the Fermilab Switchyard, Meson Target Train and M03 Meson beam dumps at 120 GeV, express MARS14 [1] simulations have been performed. A proton beam RMS spot size is {sigma}{sub x}={sigma}{sub y}=1 cm in the first two cases, while {sigma}{sub x}={sigma}{sub y}=2 cm for M03. Calculated are star density distributions (above 50 MeV) normalized per one incident proton. The configurations proposed by Chuck Brown have been implemented into the MARS code.

  20. Beam Loss Studies for the 2-MW LBNE Proton Beam Line

    SciTech Connect

    Drozhdin, A.I.; Childress, S.R.; Mokhov, N.V.; Tropin, I.S.; Zwaska, R.; /Fermilab

    2012-05-01

    Severe limits are put on allowable beam loss during extraction and transport of a 2.3 MW primary proton beam for the Long Baseline Neutrino Experiment (LBNE) at Fermilab. Detailed simulations with the STRUCT and MARS codes have evaluated the impact of beam loss of 1.6 x 10{sup 14} protons per pulse at 120 GeV, ranging from a single pulse full loss to sustained small fractional loss. It is shown that loss of a single beam pulse at 2.3 MW will result in a catastrophic event: beam pipe destruction, damaged magnets and very high levels of residual radiation inside and outside the tunnel. Acceptable beam loss limits have been determined and robust solutions developed to enable efficient proton beam operation under these constraints.

  1. Initial OTR measurements of 150 GeV protons in the Tevatron at FNAL

    SciTech Connect

    Scarpine, V.E.; Lumpkin, A.H.; Tassotto, G.R.; /Fermilab

    2006-05-01

    Fermilab has developed standard optical transition radiation (OTR) detectors as part of its Run II upgrade program for measuring intense proton and antiproton beams. These detectors utilize radiation-hardened CID cameras to image the OTR and produce high-resolution two-dimensional beam profiles. One of these detectors has been installed in the Tevatron next to the new ionization profile monitor (IPM). Initial OTR measurements are presented for 150 GeV injected coalesced and uncoalesced proton bunches. OTR images are taken for one-turn and two-turn injections over an intensity range of 1.5e11 to 3.5e11 protons. Preliminary profile measurements give uncoalesced beam size sigmas of 1.0 mm horizontally by 0.7 mm vertically and coalesced beam size sigmas of 1.8 mm horizontally by 0.70 mm vertically. OTR images are also presented for changes in the Tevatron skew quadrupole magnet currents, which produce a rotation to the OTR image, and for changes to the Tevatron RF, which can be used to measure single-turn dispersion. Operational aspects of this detector for beam studies and Tevatron tuneup are also discussed.

  2. Proton beam therapy control system

    DOEpatents

    Baumann, Michael A.; Beloussov, Alexandre V.; Bakir, Julide; Armon, Deganit; Olsen, Howard B.; Salem, Dana

    2008-07-08

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  3. Proton beam therapy control system

    DOEpatents

    Baumann, Michael A; Beloussov, Alexandre V; Bakir, Julide; Armon, Deganit; Olsen, Howard B; Salem, Dana

    2013-12-03

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  4. Proton beam therapy control system

    DOEpatents

    Baumann, Michael A; Beloussov, Alexandre V; Bakir, Julide; Armon, Deganit; Olsen, Howard B; Salem, Dana

    2013-06-25

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  5. Proton beam therapy control system

    DOEpatents

    Baumann, Michael A.; Beloussov, Alexandre V.; Bakir, Julide; Armon, Deganit; Olsen, Howard B.; Salem, Dana

    2010-09-21

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  6. HERA-B results on heavy flavour production in 920 GeV proton nucleus interactions

    NASA Astrophysics Data System (ADS)

    Kolanoski, Hermann; HERA-B Collaboration

    2005-06-01

    In this report, recent results from the HERA-B experiment on heavy flavour production in proton-nucleus interactions using a 920 GeV proton beam are presented. The topics include the production of the charmonium states J/ψ, ψ' and χc, of the D-meson states D0, D±, D*, the open beauty production cross section (b\\skew{-4}\\barb production) and the Υ production cross section. The nuclear dependence for the differential cross sections of charmonium production is discussed. The results are mainly preliminary. The report closes with a summary of the HERA-B search for pentaquark states with strangeness, which yielded quite stringent upper limits for the production of such states in hadronic environments.

  7. The clinical case for proton beam therapy

    PubMed Central

    2012-01-01

    Abstract Over the past 20 years, several proton beam treatment programs have been implemented throughout the United States. Increasingly, the number of new programs under development is growing. Proton beam therapy has the potential for improving tumor control and survival through dose escalation. It also has potential for reducing harm to normal organs through dose reduction. However, proton beam therapy is more costly than conventional x-ray therapy. This increased cost may be offset by improved function, improved quality of life, and reduced costs related to treating the late effects of therapy. Clinical research opportunities are abundant to determine which patients will gain the most benefit from proton beam therapy. We review the clinical case for proton beam therapy. Summary sentence Proton beam therapy is a technically advanced and promising form of radiation therapy. PMID:23083010

  8. Measurement of cumulative-neutron and cumulative-proton spectra in 1-GeV proton-nucleus interactions

    SciTech Connect

    Baturin, V.N.; Vikhrov, V.V.; Makarov, M.M.; Nelyubin, V.V.; Naberezhnov, A.A.; Sulimov, V.V.; Uvarov, L.N.

    1982-11-20

    A comparative study has been made of the spectra of cumulative neutrons and protons produced at an angle of 114/sup 0/ in collisions of 1-GeV protons with /sup 9/Be and /sup 12/C nuclei. The slope parameters of the inclusive neutron spectra are similar to those of the proton spectra.

  9. Investigation of GEV Proton-Induced Spallation Reactions

    NASA Astrophysics Data System (ADS)

    Hilscher, D.; Herbach, C.-M.; Jahnke, U.; Tishchenko, V. G.; Galin, J.; Lott, B.; Letourneau, A.; Peghaire, A.; Filges, D.; Goldenbaum, F.; Nünighoff, K.; Schaal, H.; Sterzenbach, G.; Wohlmuther, M.; Pienkowski, L.; Schröder, W. U.; Toke, J.

    2004-09-01

    A reliable modeling of GeV proton-induced spallation reactions is indispensable for the design of the spallation module and the target station of future accelerator driven hybrid reactors (ADS) or spallation neutron sources (ESS), in particular, to provide precise predictions for the neutron production, the radiation damage of materials (window), and the production of radioactivity (3H, 7Be etc.) in the target medium. Detailed experimental nuclear data are needed for sensitive validations and improvements of the models, whose predictive power is strongly dependent on the correct physical description of the three main stages of a spallation reaction: (i) the Intra-Nuclear-Cascade (INC) with the fast heating of the target nucleus, (ii) the de-excitation due to pre-equilibrium emission including the possibility of multi-fragmentation, and (iii) the statistical decay of thermally excited nuclei by evaporation of light particles and fission in the case of heavy nuclei. Key experimental data for this endeavor are absolute production cross sections and energy spectra for neutrons and light charged-particles (LCPs), emission of composite particles prior and post to the attainment of an equilibrated system, distribution of excitation energies deposited in the nuclei after the INC, and fission probabilities. Systematic measurements of such data are furthermore needed over large ranges of target nuclei and incident proton energies. Such data has been measured with the NESSI detector. An overview of new and previous results will be given.

  10. Nonintrusive emittance measurement of 1 GeV H- beam

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Aleksandrov, A.; Long, C.; Menshov, A.; Pogge, J.; Webster, A.; Zhukov, A.

    2012-05-01

    A laser wire based transverse phase space measurement system has been developed at the Spallation Neutron Source (SNS). The system enables a direct measurement of the transverse emittance in both directions on a 1 GeV hydrogen ion (H-) beam at the high energy beam transport (HEBT) beam line. The measurement is non-destructive and has been conducted on a neutron production H- beam. This paper describes the design, implementation, and measurement performance of the system. The experience on the installation and commissioning of the laser emittance measurement system will also be discussed.

  11. INC Model interpretation of the proton induced residual nuclide production cross sections below 2 GeV

    SciTech Connect

    Divadeenam, M.; Ward, T.E.; Spergel, M.S.; Lakatos, S.; Manche, E.P.

    1991-12-31

    For the purposes of interpreting the abundances of various isotopes in meteorites or on lunar and planetary surfaces exposed to fragmentation by cosmic rays, Webber et al. recently reported the measured total elemental and isotopic cross sections with heavy ions as projectiles on H, He, and C targets with beam energies of 0.33 - 1.7 GeV/nucleon. We employ the INC model to predict the fragmentation of the heavy ions in a hydrogen target with the inverse reaction process: proton bombardment of a heavy-ion nucleus leading to spallation products. Charge-changing and mass-changing cross sections are calculated for proton bombardment of an {sup 56}Fe target with beam energies ranging from 0.33 to 1.88 GeV. Total Z-changing and A-changing cross sections in the energy range 0.6 to 1.88 GeV are in excellent agreement with the corresponding experimental data of Webber et al. and Westfall at al., while the agreement below 0.6 GeV proton energy is not as good. The general trend of the Z-changing cross sections are reproduced by the model calculations at each proton incident energy. The interaction of 200-MeV protons with synthetic Stony Meteorite samples was undertaken to explain radionuclide production in a cosmic-ray environment. The BNL Linac 200-MeV-proton beam was used to irradiate synthetic Stony Meteorites to simulate cosmic-ray exposures corresponding to 6.4 and 16.4 million years. Each irradiated sample was analyzed with the help of a high-resolution gamma-ray spectrometer for long-lived radioisotopes. The intranuclear cascade code HETC was employed to simulate the 200-MeV proton bombardment on the meteorite samples to predict the radionuclides {sup 7}Be, {sup 22}Na, {sup 46}Mn, and {sup 56}Co produced in the experimental investigation.

  12. Evaluating the dynamic aperture evaluation for the new RHIC 250 GeV polarized proton lattice

    SciTech Connect

    Gu, X.; Luo, Y.; Fischer, W.; Huang, H.; Tepikian, S.

    2011-03-28

    To increase luminosity in the Relativistic Heavy Ion Collider's (RHIC's) polarized proton 250 GeV operations, we are considering reducing {beta}* to 0.65 m at the interaction points (IPs), and increasing bunch intensity. The new working point near the 2/3 integer will used on the ramp to preserve polarization. In addition, we plan to adjust the betatron-phase advances between IP6 and IP8 to (k+1/2)*{pi} so to lower the dynamic beta-beat from the beam-beam interaction. The effects of all these changes will impact the dynamic aperture, and hence, it must be evaluated carefully. In this article, we present the results of tracking the dynamic aperture with the proposed lattices.

  13. Conceptual Design Report. Antiproton - Proton Collider Upgrade 20 GeV Rings. Technical Components and Civil Construction May, 1988

    SciTech Connect

    1988-05-01

    This report contains a description of the design and cost estimate of two new 20 GeV rings which will be required to support the upgrade of the Fermilab Collider with a luminosity goal of 5x10 31 cm-2s-1. The new rings include an antiproton post-accumulator, denoted the Antiproton Super Booster (ASB), and a proton post-booster, denoted the Proton Super Booster (PSB). The siting of the rings is shown in Figure I-1. Both rings are capable of operation at 20 GeV, eliminating the need for ever again injecting beam into the Main Ring below transition, and significantly enhancing Main Ring performance. The Antiproton Super Booster is designed to accept and accumulate up to 4x1012 antiprotons from the existing Antiproton Accumulator, and deliver them to the Main Ring at 20 GeV for acceleration and injection into the Collider. It is also designed to accept diluted antiprotons from the Main Ring at 20 GeV for recooling. The PSB accepts 8.9 GeV protons from the existing Booster and accelerates them to 20 GeV for injection into the Main Ring. The PSB is designed to operate at 5 Hz. The siting shown in Figure I-1 has the attractive feature that it removes all Main Ring injection hardware from the AO straight section, opening the possibility of installing a third proton-antiproton interaction region in the Tevatron Collider.

  14. Production of K⁺K⁻ pairs in proton-proton collisions at 2.83 GeV

    DOE PAGESBeta

    Ye, Q. J.; Hartmann, M.; Maeda, Y.; Barsov, S.; Büscher, M.; Chiladze, D.; Dymov, S.; Dzyuba, A.; Gao, H.; Gebel, R.; et al

    2012-03-30

    Differential and total cross sections for the pp→ppK⁺K⁻ reaction have been measured at a proton beam energy of 2.83 GeV using the COSY-ANKE magnetic spectrometer. Detailed model descriptions fitted to a variety of one-dimensional distributions permit the separation of the pp→ppφ cross section from that of non-φ production. The differential spectra show that higher partial waves represent the majority of the pp→ppφ total cross section at an excess energy of 76 MeV, whose energy dependence would then seem to require some s-wave φp enhancement near threshold. The non-φ data can be described in terms of the combined effects of two-bodymore » final state interactions using the same effective scattering parameters determined from lower energy data.« less

  15. Comment on "Evidence for narrow resonant structures at W ≈1.68 GeV and W ≈1.72 GeV in real Compton scattering off the proton"

    NASA Astrophysics Data System (ADS)

    Werthmüller, D.; Witthauer, L.; Glazier, D. I.; Krusche, B.

    2015-12-01

    We comment on the statement by Kuznetsov et al. that the structure around W =1.72 GeV seen in the beam asymmetry in Compton scattering off the proton is not observed in the total cross section of η photoproduction on the neutron.

  16. Polarized proton beams since the ZGS

    SciTech Connect

    Krisch, A.D.

    1994-12-31

    The author discusses research involving polarized proton beams since the ZGS`s demise. He begins by reminding the attendee that in 1973 the ZGS accelerated the world`s first high energy polarized proton beam; all in attendance at this meeting can be proud of this accomplishment. A few ZGS polarized proton beam experiments were done in the early 1970`s; then from about 1976 until 1 October 1979, the majority of the ZGS running time was polarized running. A great deal of fundamental physics was done with the polarized beam when the ZGS ran as a dedicated polarized proton beam from about Fall 1977 until it shut down on 1 October 1979. The newly created polarization enthusiats then dispersed; some spread polarized seeds al over the world by polarizing beams elsewhere; some wound up running the High Energy and SSC programs at DOE.

  17. Synchro-betatron resonances in the 8 GeV proton driver

    SciTech Connect

    Shoroku Ohnuma

    2002-12-02

    The major difference of these two versions is the size (circumference) and the maximum energy. In the first study, the circumference is chosen to be 711.3m, which is 1.5 times the present Booster, with the maximum energy of 16 GeV. In the second version, it is mandated to be the same as Booster together with the same maximum energy of 8 GeV. One of the major impacts of the reduced size of the ring is the inevitable reduction in the total length of available space for injection/collimation/extraction systems and for rf cavities, 14 slots of 7.43m each in the smaller ring compared with 24 slots of 6.15m each in the larger ring. Since each cavity occupies a slot of 2.35m and 22 cavities are desirable, seven or eight slots out of 14 in the smaller ring must be reserved for rf, only six or seven remaining for all other systems. The constraint in space is particularly troublesome for the extraction system since the beam loss at extraction (at the highest beam energy) is the major concern of any high intensity proton machines.

  18. ALPtraum: ALP production in proton beam dump experiments

    NASA Astrophysics Data System (ADS)

    Döbrich, Babette; Jaeckel, Joerg; Kahlhoefer, Felix; Ringwald, Andreas; Schmidt-Hoberg, Kai

    2016-02-01

    With their high beam energy and intensity, existing and near-future proton beam dumps provide an excellent opportunity to search for new very weakly coupled particles in the MeV to GeV mass range. One particularly interesting example is a so-called axion-like particle (ALP), i.e. a pseudoscalar coupled to two photons. The challenge in proton beam dumps is to reliably calculate the production of the new particles from the interactions of two composite objects, the proton and the target atoms. In this work we argue that Primakoff production of ALPs proceeds in a momentum range where production rates and angular distributions can be determined to sufficient precision using simple electromagnetic form factors. Reanalysing past proton beam dump experiments for this production channel, we derive novel constraints on the parameter space for ALPs. We show that the NA62 experiment at CERN could probe unexplored parameter space by running in `dump mode' for a few days and discuss opportunities for future experiments such as SHiP.

  19. Longitudinal Spin Transfer of LAMBDA and LAMBDA-bar Hyperons in Polarized Proton-Proton Collisions at sq root(s) = 200 GeV

    SciTech Connect

    Sichtermann, Ernst

    2009-08-04

    The longitudinal spin transfer D{sub LL} of LAMBDA and LAMBDA-bar hyperons produced with large transverse momenta P{sub T} in polarized proton-proton collisions is sensitive to the helicity distribution functions of strange quarks and anti-quarks, and to polarized fragmentation functions. This contribution reports a measurement of the longitudinal spin transfer D{sub LL} in the inclusive production of LAMBDA and LAMBDA-bar hyperons at central rapidities in polarized proton-proton collisions at a center of mass energy of sq root(s) = 200 GeV. The data were collected with the STAR experiment at RHIC and correspond to a approx =3 pb{sup -1} luminosity and a approx =50% beam polarization.

  20. Measurements of Compton Scattering on the Proton at 2 - 6 GeV

    SciTech Connect

    Danagoulian, Areg

    2006-05-01

    Similar to elastic electron scattering, Compton Scattering on the proton at high momentum transfers(and high p⊥) can be an effective method to study its short-distance structure. An experiment has been carried out to measure the cross sections for Real Compton Scattering (RCS) on the proton for 2.3-5.7 GeV electron beam energies and a wide distribution of large scattering angles. The 25 kinematic settings sampled a domain of s = 5-11(GeV/c)2,-t = -7(GeV/c)2 and -u = 0.5-6.5(GeV/c)2. In addition, a measurement of longitudinal and transverse polarization transfer asymmetries was made at a 3.48 GeV beam energy and a scattering angle of θcm = 120o. These measurements were performed to test the existing theoretical mechanisms for this process as well as to determine RCS form factors. At the heart of the scientific motivation is the desire to understand the manner in which a nucleon interacts with external excitations at the above listed energies, by comparing and contrasting the two existing models – Leading Twist Mechanism and Soft Overlap “Handbag” Mechanism – and identify the dominant mechanism. Furthermore, the Handbag Mechanism allows one to calculate reaction observables in the framework of Generalized Parton Distributions (GPD), which have the function of bridging the wide gap between the exclusive(form factors) and inclusive(parton distribution functions) description of the proton. The experiment was conducted in Hall A of Thomas Jefferson National Accelerator Facility(Jefferson Lab). It used a polarized and unpolarized electron beam, a 6% copper radiator with the thickness of 6.1% radiation lengths (to produce a bremsstrahlung photon beam), the Hall A liquid hydrogen target, a high resolution spectrometer with a focal plane polarimeter, and a photon hodoscope calorimeter. Results of the differential cross sections are presented, and discussed in the general context of the scientific motivation.

  1. LATTICES FOR HIGH-POWER PROTON BEAM ACCELERATION AND SECONDARY BEAM COLLECTION AND COOLING.

    SciTech Connect

    WANG, S.; WEI, J.; BROWN, K.; GARDNER, C.; LEE, Y.Y.; LOWENSTEIN, D.; PEGGS, S.; SIMOS, N.

    2006-06-23

    Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.

  2. The ratio R{sub dp} of the quasielastic nd {yields} p(nn) to the elastic np {yields} pn charge-exchange-process yields at the proton emitting angle {theta}{sub p,lab} = 0 deg. over 0.55-2.0 GeV neutron beam energy region. Experimental results

    SciTech Connect

    Sharov, V. I. Morozov, A. A.; Shindin, R. A.; Antonenko, V. G.; Borzakov, S. B.; Borzunov, Yu. T.; Chernykh, E. V.; Chumakov, V. F.; Dolgii, S. A.; Finger, M.; Finger, M.; Golovanov, L. B.; Guriev, D. K.; Janata, A.; Kirillov, A. D.; Kovalenko, A. D.; Krasnov, V. A.; Kuzmin, N. A.; Kurilkin, A. K.; Kurilkin, P. K.

    2009-06-15

    New experimental results on ratio R{sub dp} of the quasielastic charge-exchange yield at the outgoing proton angle {theta}{sub p,lab} = 0 deg. for the nd {yields} p(nn) reaction to the elastic np {yields} pn charge-exchange yield, are presented. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the JINR (Dubna) at the neutron-beam kinetic energies of 0.55, 0.8, 1.0, 1.2, 1.4, 1.8, and 2.0 GeV. The intense neutron beam with small momentum spread was produced by breakup of deuterons which were accelerated and extracted to the experimental hall. In both reactions mentioned above the outgoing protons with the momenta p{sub p} approximately equal to the neutron-beam momentum p{sub n,beam} were detected in the directions close to the direction of incident neutrons, i.e., in the vicinity of the scattering angle {theta}{sub p,lab} = 0 deg. Measured in the same data-taking runs, the angular distributions of the charge-exchange-reaction products were corrected for the well-known instrumental effects and averaged in the vicinity of the incident-neutron-beam direction. These corrected angular distributions for every of nd {yields} p(nn) and np {yields} pn charge-exchange processes were proportional to the differential cross sections of the corresponding reactions. The data were accumulated by Delta-Sigma setup magnetic spectrometer with two sets of multiwire proportional chambers located upstream and downstream of the momentum analyzing magnet. Inelastic processes were considerably reduced by the additional detectors surrounding the hydrogen and deuterium targets. The time-of-flight system was applied to identify the detected particles. The accumulated data treatment and analysis, as well as possible sources of the systematic errors are discussed.

  3. Prompt neutrino results from a proton beam dump experiment

    NASA Astrophysics Data System (ADS)

    Berge, P.; Dydak, F.; Guyot, C.; Hagelberg, R.; Merlo, J. P.; Ranjard, F.; Rothberg, J.; Steinberger, J.; Taureg, H.; von Rüden, W.; Wahl, H.; Williams, R. W.; Wotschack, J.; Blümer, H.; Buchholz, P.; Duda, J.; Eisele, F.; Kleinknecht, K.; Knobloch, J.; Pollmann, D.; Pszola, B.; Renk, B.; Belusević, R.; Falkenburg, B.; Flottmann, T.; de Groot, J. G. H.; Geweniger, C.; Hepp, V.; Keilwerth, H.; Tittel, K.; Debu, P.; Para, A.; Perez, P.; Peyaud, B.; Rander, J.; Schuller, J. P.; Turlay, R.; Abramowicz, H.; Królikowski, J.

    1992-06-01

    A study of prompt neutrino events from 400 GeV protons on a beam-dump is presented. The ratio of electron- to muon-neutrino rates is 0.86±0.14, in agreement with e-μ universality. The anti-neutrino to neutrino flux ratio isbar v_μ /v_μ = 0.81 ± 0.19. The absolute rates and distributions observed are shown to be in quantitative agreement with the known properties of charmedquark production in hadron collisions.

  4. 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.

  5. Fan-beam intensity modulated proton therapy

    PubMed Central

    Hill, Patrick; Westerly, David; Mackie, Thomas

    2013-01-01

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques. Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets. Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage

  6. Fan-beam intensity modulated proton therapy

    SciTech Connect

    Hill, Patrick; Westerly, David; Mackie, Thomas

    2013-11-15

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques.Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets.Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage

  7. Comment on 'Proton beam monitor chamber calibration'.

    PubMed

    Palmans, Hugo; Vatnitsky, Stanislav M

    2016-09-01

    We comment on a recent article (Gomà et al 2014 Phys. Med. Biol. 59 4961-71) which compares different routes of reference dosimetry for the energy dependent beam monitor calibration in scanned proton beams. In this article, a 3% discrepancy is reported between a Faraday cup and a plane-parallel ionization chamber in the experimental determination of the number of protons per monitor unit. It is further claimed that similar discrepancies between calorimetry and ionization chamber based dosimetry indicate that [Formula: see text]-values tabulated for proton beams in IAEA TRS-398 might be overestimated. In this commentary we show, however, that this supporting argument misrepresents the evidence in the literature and that the results presented, together with published data, rather confirm that there exist unresolved problems with Faraday cup dosimetry. We also show that the comparison in terms of the number of protons gives a biased view on the uncertainty estimates for both detectors while the quantity of interest is absorbed dose to water or dose-area-product to water, even if a beam monitor is calibrated in terms of the number of protons. Gomà et al (2014 Phys. Med. Biol. 59 4961-71) also report on the discrepancy between cylindrical and plane-parallel ionization chambers and confirm experimentally that in the presence of a depth dose gradient, theoretical values of the effective point of measurement, or alternatively a gradient correction factor, account for the discrepancy. We believe this does not point to an error or shortcoming of IAEA TRS-398, which prescribes taking the centre of cylindrical ionization chambers as reference point, since it recommends reference dosimetry to be performed in the absence of a depth dose gradient. But these observations reveal that important aspects of beam monitor calibration in scanned proton beams are not addressed in IAEA TRS-398 given that those types of beams were not widely implemented at the time of its publication

  8. Search for exotic baryons with hidden strangeness in proton diffractive production at the energy of 70 GeV

    NASA Astrophysics Data System (ADS)

    Antipov, Yu. M.; Artamonov, A. V.; Batarin, V. A.; Eroshin, O. V.; Golovkin, S. V.; Gorin, Yu. P.; Govorun, V. N.; Isaev, A. N.; Kozhevnikov, A. P.; Kubarovsky, V. P.; Kurshetsov, V. F.; Landsberg, L. G.; Medovikov, V. A.; Molchanov, V. V.; Mukhin, V. A.; Patalakha, D. I.; Petrenko, S. V.; Petrukhin, A. I.; Senko, V. A.; Shalanda, N. A.; Sytin, A. N.; Vaniev, V. S.; Vavilov, D. V.; Victorov, V. A.; Yakimchuk, V. I.; Zimin, S. A.; Kolganov, V. Z.; Lomkatsi, G. S.; Nilov, A. F.; Smolyankin, V. T.

    2002-11-01

    The first preliminary results from the upgraded SPHINX spectrometer, working in the proton beam with the energy of 70 GeV of the IHEP accelerator, are presented. The data for the reaction p + N ⊒ [Σ0 K +] + N based on new statistics are in good agreement with our previous data and strongly support the existence of the X (2000) state (with an increase in statistics for this state by a factor of ˜5). We also observed radiative decay of Λ(1520) → Λγ. The significant increase in statistics for many diffractive-production reactions will allow us to study them in great detail.

  9. Search for exotic baryons with hidden strangeness in proton diffractive production at the energy of 70 GeV

    NASA Astrophysics Data System (ADS)

    Kurshetsov, Victor

    2002-06-01

    First preliminary results from upgraded SPHINX spectrometer, working in the proton beam with the energy of 70 GeV of IHEP accelerator, are presented. The data for the reaction p + N [right arrow] [Sigma]0K+ + N based on a new statistics are in a good agreement with our previous data and strongly supports the existence of X(2000) state (with the increase of statistics for this state by a factor of approx 5). We also observed radiative decay of Lambda(1520) [right arrow] Lambda + gamma. The significant increase of statistics for many diffractive production reactions will allow us to study them in great detail.

  10. Eta' photoproduction on the proton for photon energies from 1.527 to 2.227 GeV.

    PubMed

    Dugger, M; Ball, J P; Collins, P; Pasyuk, E; Ritchie, B G; Adams, G; Ambrozewicz, P; Anciant, E; Anghinolfi, M; Asavapibhop, B; Asryan, G; Audit, G; Avakian, H; Bagdasaryan, H; Baillie, N; Baltzell, N A; Barrow, S; Batourine, V; Battaglieri, M; Beard, K; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Berman, B L; Bianchi, N; Biselli, A S; Bonner, B E; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Burkert, V D; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Carnahan, B; Chen, S; Cole, P L; Coleman, A; Coltharp, P; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Credé, V; Cummings, J P; De Sanctis, E; DeVita, R; Degtyarenko, P V; Denizli, H; Dennis, L; Deur, A; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Donnelly, J; Doughty, D; Dragovitsch, P; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Eugenio, P; Fatemi, R; Fedotov, G; Feldman, G; Feuerbach, R J; Forest, T A; Funsten, H; Garçon, M; Gavalian, G; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Guo, L; Gyurjyan, V; Hadjidakis, C; Hakobyan, R S; Hardie, J; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hu, J; Huertas, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Ito, M M; Jenkins, D; Jo, H S; Joo, K; Juengst, H G; Kellie, J D; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Klusman, M; Kossov, M; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Lee, T; Lima, A C S; Livingston, K; Lukashin, K; Manak, J J; Marchand, C; Maximon, L C; McAleer, S; McKinnon, B; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Minehart, R; Mirazita, M; Miskimen, R; Mokeev, V; Morrow, S A; Muccifora, V; Mueller, J; Mutchler, G S; Nadel-Turonski, P; Napolitano, J; Nasseripour, R; Niccolai, S; Niculescu, G; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Paterson, C; Philips, S A; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ronchetti, F; Rosner, G; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Salgado, C; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Shafi, A; Sharabian, Y G; Shaw, J; Simionatto, S; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Spraker, M; Stavinsky, A; Stepanyan, S S; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Taylor, S; Tedeschi, D J; Thoma, U; Thompson, R; Tkabladze, A; Tkachenko, S; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weller, H; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zana, L; Zhang, J

    2006-02-17

    Differential cross sections for the reaction gamma p --> eta' p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data suggest for the first time the coupling of the eta'N channel to both the S11(1535) and P11(1710) resonances, known to couple strongly to the etaN channel in photoproduction on the proton, and the importance of J = 3/2 resonances in the process. PMID:16605984

  11. Beam dynamics studies of the 8 GeV Linac at FNAL

    SciTech Connect

    Ostroumov, P.N.; Mustapha, B.; Carneiro, J.-P.; /Fermilab

    2008-11-01

    The proposed 8-GeV proton driver (PD) linac at FNAL includes a front end up to {approx}420 MeV operating at 325 MHz and a high energy section at 1300 MHz. A normal conducting RFQ and short CH type resonators are being developed for the initial acceleration of the H-minus or proton beam up to 10 MeV. From 10 MeV to {approx}420 MeV, the voltage gain is provided by superconducting (SC) spoke-loaded cavities. In the high-energy section, the acceleration will be provided by the International Linear Collider (ILC)-style SC elliptical cell cavities. To employ existing, readily available klystrons, an RF power fan out from high-power klystrons to multiple cavities is being developed. The beam dynamics simulation code TRACK, available in both serial and parallel versions, has been updated to include all known H-minus stripping mechanisms to predict the exact location of beam losses. An iterative simulation procedure is being developed to interact with a transient beam loading model taking into account RF feedback and feedforward systems.

  12. Radioisotope yields from 1.85-GeV protons on Mo and 1.85- and 5.0-GeV protons on Te

    SciTech Connect

    Bardayan, D.W.; Hindi, M.M.; Barghouty, A.F.

    1995-05-01

    Radioisotope yields from 1.85-GeV proton interactions in a natural isotopic composition Mo target and those from 1.85- and 5.0-GeV protons in natural Te targets were measured at Lawrence Berkeley Laboratory`s Bevatron. The radioisotope yields were determined by {gamma}-counting the targets using a 100-cm{sup 3} coaxial Ge detector following the irradiations. Cross sections were determined for the production of 31 radioactive nuclides, ranging from Z = 35, A = 74, to Z = 43, A = 97, from the Mo target and for 47 radioactive nuclides, ranging from Z = 35, A = 75, to Z = 53, A = 130 from the Te targets.

  13. Oblique incidence for broad monoenergetic proton beams

    SciTech Connect

    Jette, David; Yuan Jiankui; Chen Weimin

    2010-11-15

    Purpose: The depth dose of a monoenergetic broad parallel proton beam has been modeled in a number of ways, but evidently not yet for oblique incidence. The purpose of this investigation is to find an accurate analytic formula for this case, which can then be used to model the depth dose of a broad beam with an initial Gaussian angular distribution. Methods: The Bortfeld model of depth dose in a broad normally incident proton beam has been extended to the case of oblique incidence. This extension uses an empirically determined Gaussian parameter {sigma}{sub x} which (roughly) characterizes the off-axis dose of a proton pencil beam. As with Bortfeld's work, the modeling is done in terms of parabolic cylinder functions. To obtain the depth dose for an initial angular distribution, the result is integrated over the angle of incidence, weighted by a Gaussian probability function. The predictions of the theory have been compared to MCNPX Monte Carlo calculations for four phantom materials (water, bone, aluminum, and copper) and for initial proton energies of 50, 100, 150, 200, and 250 MeV. Results: Comparisons of the depth dose predicted by this theory with Monte Carlo calculations have established that with very good accuracy, {sigma}{sub x} can be taken to be independent both of the depth and of the angle of incidence. As a function of initial proton range or of initial proton energy, {sigma}{sub x} has been found to obey a power law to very high accuracy. Good fits to Monte Carlo calculations have also been found for an initial Gaussian angular distribution. Conclusions: This investigation is the first step in the accurate modeling of a proton pencil beam with initial Gaussian angular distribution. It provides the longitudinal factor, with its Bragg peak buildup and sharp distal falloff. A transverse factor must still be incorporated into this theory and this will give the lateral penumbra of a collimated proton beam. Also, it will be necessary to model the dose of

  14. High-Efficiency Volume Reflection of an Ultrarelativistic Proton Beam with a Bent Silicon Crystal

    SciTech Connect

    Scandale, Walter; Still, Dean A.; Baricordi, Stefano; Dalpiaz, Pietro; Fiorini, Massimiliano; Guidi, Vincenzo; Martinelli, Giuliano; Mazzolari, Andrea; Milan, Emiliano; Ambrosi, Giovanni; Azzarello, Philipp; Battiston, Roberto; Bertucci, Bruna; Burger, William J.; Ionica, Maria; Zuccon, Paolo; Cavoto, Gianluca; Santacesaria, Roberta; Valente, Paolo; Vallazza, Erik

    2007-04-13

    The volume reflection phenomenon was detected while investigating 400 GeV proton interactions with bent silicon crystals in the external beam H8 of the CERN Super Proton Synchrotron. Such a process was observed for a wide interval of crystal orientations relative to the beam axis, and its efficiency exceeds 95%, thereby surpassing any previously observed value. These observations suggest new perspectives for the manipulation of high-energy beams, e.g., for collimation and extraction in new-generation hadron colliders, such as the CERN Large Hadron Collider.

  15. Production and Phi(t) Correlations of D Mesons in 800 Gev/c Proton-Proton Interactions.

    NASA Astrophysics Data System (ADS)

    Zabounidis, Christos

    This thesis presents results derived from data collected by Fermilab experiment E743. LEBC, a small, rapid cycling, liquid hydrogen bubble chamber coupled with the FMPS, a conventional spectrometer with particle identification, was exposed to an 800 GeV proton beam. The sample of data described in this thesis corresponds to a total accumulated statistics equivalent to a sensitivity of 9.0 +/- 1.0 events/mub. This thesis studies the inclusive production properties of D/D mesons and the phi_{T } angular correlation of D D pairs. The total cross section sigma(D/| D) is 62_sp{-10}{+13} mub. The differential cross section parametrized by the empirical formula {d^2 sigma(D/| D)}over{dx_ {F}dp_sp{T}{2}} ~ (1 - | x_{F}|)^ {n}e^{-bp_sp{T}{2 }} yields n = 8.8_sp{ -1.8}{+2.1} and b = 0.79 _sp{-0.15}{+0.17} (GeV/c) ^2. The measurement of phi _{T} yields < phi_{T} > = 115 +/- 29 degrees. The comparison of these results to fusion model calculations results in good agreement.

  16. Sparse-view proton computed tomography using modulated proton beams

    SciTech Connect

    Lee, Jiseoc; Kim, Changhwan; Cho, Seungryong; Min, Byungjun; Kwak, Jungwon; Park, Seyjoon; Lee, Se Byeong; Park, Sungyong

    2015-02-15

    Purpose: Proton imaging that uses a modulated proton beam and an intensity detector allows a relatively fast image acquisition compared to the imaging approach based on a trajectory tracking detector. In addition, it requires a relatively simple implementation in a conventional proton therapy equipment. The model of geometric straight ray assumed in conventional computed tomography (CT) image reconstruction is however challenged by multiple-Coulomb scattering and energy straggling in the proton imaging. Radiation dose to the patient is another important issue that has to be taken care of for practical applications. In this work, the authors have investigated iterative image reconstructions after a deconvolution of the sparsely view-sampled data to address these issues in proton CT. Methods: Proton projection images were acquired using the modulated proton beams and the EBT2 film as an intensity detector. Four electron-density cylinders representing normal soft tissues and bone were used as imaged object and scanned at 40 views that are equally separated over 360°. Digitized film images were converted to water-equivalent thickness by use of an empirically derived conversion curve. For improving the image quality, a deconvolution-based image deblurring with an empirically acquired point spread function was employed. They have implemented iterative image reconstruction algorithms such as adaptive steepest descent-projection onto convex sets (ASD-POCS), superiorization method–projection onto convex sets (SM-POCS), superiorization method–expectation maximization (SM-EM), and expectation maximization-total variation minimization (EM-TV). Performance of the four image reconstruction algorithms was analyzed and compared quantitatively via contrast-to-noise ratio (CNR) and root-mean-square-error (RMSE). Results: Objects of higher electron density have been reconstructed more accurately than those of lower density objects. The bone, for example, has been reconstructed

  17. Studies of beam halo formation in the 12GeV CEBAF design

    SciTech Connect

    Yves Roblin; Arne Freyberger

    2007-06-01

    Beam halo formation in the beam transport design for the Jefferson Lab 12GeV upgrade was investigated using 12GeV beam transport models as well as data from 6GeV CEBAF operations. Various halo sources were considered; these covered both nuclear interactions with beam gas as well as optics-related effects such as non linearities in the magnetic fields of the transport elements. Halo due to beam gas scattering was found to be less of a problem at 12GeV compared to the 6GeV machine. Halo due to non linear effects of magnetic elements was characterized as a function of beam orbit and functional forms of the distribution were derived. These functional forms were used as inputs in subsequent detector optimizations studies.

  18. Beam Dynamics Aspects of High Current Beams in a Superconducting Proton Linac

    NASA Astrophysics Data System (ADS)

    Bellomo, Giovanni; Pagani, Carlo; Pierini, Paolo

    1997-05-01

    High current CW proton linac accelerators have been recently proposed for nuclear waste transmutation and concurrent energy production. In most of the designs the high energy part (100 MeV up to 1-2 GeV) of the linac employs low frequency superconducting structures (352-700 MHz). Here we present beam dynamics issues for the high current (10-50 mA) beams in the superconducting section of such an accelerator, based on 352 MHz β-graded, LEP style cavities, as proposed at Linac 96(C. Pagani, G. Bellomo, P. Pierini, ``A High Current Proton Linac with 352 MHz SC Cavities'', Proceedings of the XVIII Int. Linear Acc. Conf., eds. C. Hill, M. Vretenar, CERN 96-07, 15 November 1996). In particular, smooth beam propagation along the linac has been reached with decreasing phase advances along the linac, and the design has been updated to match the beam dynamics results. Mismatching oscillations are discussed, as they are considered to cause beam halo and, consequently, beam losses.

  19. Studies of beam heating of proton beam profile monitor SEM's

    SciTech Connect

    Pavlovich, Zarko; Osiecki, Thomas H.; Kopp, Sacha E.; /Texas U.

    2005-05-01

    The authors present calculations of the expected temperature rise of proton beam profile monitors due to beam heating. The profile monitors are secondary emission monitors (SEM's) to be made of Titanium foils. The heating is studied to understand whether there is any loss of tension or alignment of such devices. Additionally, calculations of thermally-induced dynamic stress are presented. Ti foil is compared to other materials and also to wire SEM's. The calculations were initially performed for the NuMI beam, where the per-pulse intensity is quite high; for completeness the calculations are also performed for other beam energies and intensities.

  20. Method and apparatus for laser-controlled proton beam radiology

    DOEpatents

    Johnstone, Carol J.

    1998-01-01

    A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H.sup.- beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H.sup.- beam and laser beam to produce a neutral beam therefrom within a subsection of the H.sup.- beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H.sup.- beam in order to form the neutral beam in subsections of the H.sup.- beam. As the scanning laser moves across the H.sup.- beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser.

  1. Method and apparatus for laser-controlled proton beam radiology

    DOEpatents

    Johnstone, C.J.

    1998-06-02

    A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H{sup {minus}} beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H{sup {minus}} beam and laser beam to produce a neutral beam therefrom within a subsection of the H{sup {minus}} beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H{sup {minus}} beam in order to form the neutral beam in subsections of the H{sup {minus}} beam. As the scanning laser moves across the H{sup {minus}} beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser. 9 figs.

  2. Innovative radiotherapy of sarcoma: Proton beam radiation.

    PubMed

    DeLaney, Thomas F; Haas, Rick L M

    2016-07-01

    This review on proton beam radiotherapy (PBT) focusses on an historical overview, cost-effectiveness, techniques, acute and late toxicities and clinical results of PBT for sarcoma patients. PBT has gained its place among the armamentarium of modern radiotherapy techniques. For selected patients, it can be cost-effective. PMID:27258968

  3. Nuclear Dependence of Proton-Induced Drell-Yan Dimuon Production at 120 GeV at Seaquest

    SciTech Connect

    Dannowitz, Bryan P.

    2016-01-01

    A measurement of the atomic mass (A) dependence of p + A → µ+µ- + X Drell-Yan dimuons produced by 120 GeV protons is presented here. The data was taken by the SeaQuest experiment at Fermilab using a proton beam extracted from its Main Injector. Over 61,000 dimuon pairs were recorded with invariant mass 4.2 < Mγ* < 10 GeV and target parton momentum fraction 0.1 ≤ x2 ≤ 0.5 for nuclear targets 1H, 2H, C, Fe, and W . The ratio of dimuon yields per nucleon (Y ) for heavy nuclei versus 2H, RDY = 2 2 Y (A)/Y ( H) ≈ u¯(A)(x)/u¯( H)(x), is sensitive to modifications in the anti-quark sea distributions in nuclei for the case of proton-induced Drell-Yan. The data analyzed here and in the future of SeaQuest will provide tighter constraints on various models that attempt to define the anomalous behavior of nuclear modification as seen in deep inelastic lepton scattering, a phenomenon generally known as the EMC effect.

  4. First Proton-Proton Collisions at the LHC as Observed with the ALICE Detector: Measurement of the Charged Particle Pseudorapidity Density at s = 900 GeV

    SciTech Connect

    Aamodt, K.; Awes, Terry C; Enokizono, Akitomo; Read Jr, Kenneth F; Silvermyr, David O; Collaboration, The ALICE

    2010-01-01

    On 23rd November 2009, during the early commissioning of the CERN Large Hadron Collider (LHC), two counter-rotating proton bunches were circulated for the first time concurrently in the machine, at the LHC injection energy of 450 GeV per beam. Although the proton intensity was very low, with only one pilot bunch per beam, and no systematic attempt was made to optimize the collision optics, all LHC experiments reported a number of collision candidates. In the ALICE experiment, the collision region was centred very well in both the longitudinal and transverse directions and 284 events were recorded in coincidence with the two passing proton bunches. The events were immediately reconstructed and analyzed both online and offline. We have used these events to measure the pseudorapidity density of charged primary particles in the central region. In the range |{eta}|<0.5, we obtain dN{sub ch}/d{eta} = 3.10 {+-} 0.13(stat.) {+-} 0.22(syst.) for all inelastic interactions, and dN{sub ch}/d{eta} = 3.51 {+-} 0.15(stat.) {+-} 0.25(syst.) for non-single diffractive interactions. These results are consistent with previous measurements in proton-antiproton interactions at the same centre-of-mass energy at the CERN Sp {bar p} S collider. They also illustrate the excellent functioning and rapid progress of the LHC accelerator, and of both the hardware and software of the ALICE experiment, in this early start-up phase.

  5. Golden beam data for proton pencil-beam scanning

    NASA Astrophysics Data System (ADS)

    Clasie, Benjamin; Depauw, Nicolas; Fransen, Maurice; Gomà, Carles; Panahandeh, Hamid Reza; Seco, Joao; Flanz, Jacob B.; Kooy, Hanne M.

    2012-03-01

    Proton, as well as other ion, beams applied by electro-magnetic deflection in pencil-beam scanning (PBS) are minimally perturbed and thus can be quantified a priori by their fundamental interactions in a medium. This a priori quantification permits an optimal reduction of characterizing measurements on a particular PBS delivery system. The combination of a priori quantification and measurements will then suffice to fully describe the physical interactions necessary for treatment planning purposes. We consider, for proton beams, these interactions and derive a ‘Golden’ beam data set. The Golden beam data set quantifies the pristine Bragg peak depth-dose distribution in terms of primary, multiple Coulomb scatter, and secondary, nuclear scatter, components. The set reduces the required measurements on a PBS delivery system to the measurement of energy spread and initial phase space as a function of energy. The depth doses are described in absolute units of Gy(RBE) mm2 Gp-1, where Gp equals 109 (giga) protons, thus providing a direct mapping from treatment planning parameters to integrated beam current. We used these Golden beam data on our PBS delivery systems and demonstrated that they yield absolute dosimetry well within clinical tolerance.

  6. Golden beam data for proton pencil-beam scanning.

    PubMed

    Clasie, Benjamin; Depauw, Nicolas; Fransen, Maurice; Gomà, Carles; Panahandeh, Hamid Reza; Seco, Joao; Flanz, Jacob B; Kooy, Hanne M

    2012-03-01

    Proton, as well as other ion, beams applied by electro-magnetic deflection in pencil-beam scanning (PBS) are minimally perturbed and thus can be quantified a priori by their fundamental interactions in a medium. This a priori quantification permits an optimal reduction of characterizing measurements on a particular PBS delivery system. The combination of a priori quantification and measurements will then suffice to fully describe the physical interactions necessary for treatment planning purposes. We consider, for proton beams, these interactions and derive a 'Golden' beam data set. The Golden beam data set quantifies the pristine Bragg peak depth-dose distribution in terms of primary, multiple Coulomb scatter, and secondary, nuclear scatter, components. The set reduces the required measurements on a PBS delivery system to the measurement of energy spread and initial phase space as a function of energy. The depth doses are described in absolute units of Gy(RBE) mm² Gp⁻¹, where Gp equals 10⁹ (giga) protons, thus providing a direct mapping from treatment planning parameters to integrated beam current. We used these Golden beam data on our PBS delivery systems and demonstrated that they yield absolute dosimetry well within clinical tolerance. PMID:22330090

  7. Precision Electron-Beam Polarimetry at 1 GeV Using Diamond Microstrip Detectors

    NASA Astrophysics Data System (ADS)

    Narayan, A.; Jones, D.; Cornejo, J. C.; Dalton, M. M.; Deconinck, W.; Dutta, D.; Gaskell, D.; Martin, J. W.; Paschke, K. D.; Tvaskis, V.; Asaturyan, A.; Benesch, J.; Cates, G.; Cavness, B. S.; Dillon-Townes, L. A.; Hays, G.; Ihloff, E.; Jones, R.; King, P. M.; Kowalski, S.; Kurchaninov, L.; Lee, L.; McCreary, A.; McDonald, M.; Micherdzinska, A.; Mkrtchyan, A.; Mkrtchyan, H.; Nelyubin, V.; Page, S.; Ramsay, W. D.; Solvignon, P.; Storey, D.; Tobias, A.; Urban, E.; Vidal, C.; Waidyawansa, B.; Wang, P.; Zhamkotchyan, S.

    2016-01-01

    We report on the highest precision yet achieved in the measurement of the polarization of a low-energy, O (1 GeV ) , continuous-wave (CW) electron beam, accomplished using a new polarimeter based on electron-photon scattering, in Hall C at Jefferson Lab. A number of technical innovations were necessary, including a novel method for precise control of the laser polarization in a cavity and a novel diamond microstrip detector that was able to capture most of the spectrum of scattered electrons. The data analysis technique exploited track finding, the high granularity of the detector, and its large acceptance. The polarization of the 180 -μ A , 1.16-GeV electron beam was measured with a statistical precision of <1 % per hour and a systematic uncertainty of 0.59%. This exceeds the level of precision required by the Qweak experiment, a measurement of the weak vector charge of the proton. Proposed future low-energy experiments require polarization uncertainty <0.4 %, and this result represents an important demonstration of that possibility. This measurement is the first use of diamond detectors for particle tracking in an experiment. It demonstrates the stable operation of a diamond-based tracking detector in a high radiation environment, for two years.

  8. Design of Injection and Extraction at an 8-GeV Booster Ring and the J-PARC Main Ring for Multi-MW Output Beam Power

    NASA Astrophysics Data System (ADS)

    Harada, Hiroyuki; Hotchi, Hideaki; Igarashi, Susumu; Sato, Yoichi; Koseki, Tadashi

    The 240-kW output beam power in the MR has been achieved for a 30-GeV user operation with the repetition cycle of 2.48 sec and injecting proton beams of 380-kW equivalent intensity from RCS. The MR aims to realize 750-kW beam operation with faster repetition cycle of ˜1 s and injecting proton beams of 600-kW equivalent intensity from RCS. The MR is developing the new type power supplies of MR main magnets and high-impedance core of MR RF cavities toward faster repetition cycle. We are now exploring the further beam power upgrade scenario of the J-PARC accelerators. As one possible scenario toward a multi-MW output beam power from MR, a new 8-GeV booster ring (BR) between RCS and MR is also designed. The injection energy of the MR increases from present 3-GeV to 8-GeV. The higher injection energy of the MR would be able to mitigate a space charge force in MR injection energy region and secure the acceptance clearance of beam from MR physical aperture. In this paper, the designed injection and extraction system of BR are described. Additionally, a new concept of BR extraction and MR injection toward multi-MW output beam power are described.

  9. Lambda and Antilambda Polarization in Proton-Proton Interactions from Sqrt. S = 31 TO 62 GEV.

    NASA Astrophysics Data System (ADS)

    Sherwood, Peter

    This thesis presents measurements of Lambda^0, |Lambda ^0, and Sigma^0 production made using experiment R608 at the CERN ISR. The Lambda^0 cross sections have been measured in the range 0.20 < x _{rm F}< 0.96 and for p _{rm t} up to 2.2 GeV/c. The invariant cross section, E*d^3sigma /dp^3, is presented in x _{rm F} bins, plotted against p_{rm t}^2 . The function Aexp(-(bp _{rm t}^2 + cp _{rm t}^4)) was found to be a good fit to the data. The cross section was integrated with respect to p_{rm t} ^2 to obtain the x_{ rm F} dependence. The Lambda ^0 shows a rapid fall-off with x _{rm F} up to x_ {rm F}~ 0.4, and thereafter exhibits a small decline to zero at x_{ rm F}~ 1, as is typical for baryons produced in proton fragmentation processes. The |Lambda^0 cross section was measured in the region 0.2 < x_{rm F}< 0.5. The invariant cross section was found to be well described by the function Aexp(-bp _{rm t}^2). Unlike the Lambda^0, the |Lambda^0 cross section falls rapidly with x_{rm F}. The Sigma^0 cross section was measured in the region 0.5 < p_{rm t}< 1.2 GeV/c and 0.3 < x_{rm F}< 0.7. In this region, the Lambda ^0/Sigma^0 ratio is 0.376 +/- 0.044. The Sigma^0 is thus the dominant contributor to non-direct Lambda^0 production. The Lambda^0 polarization was measured as function of surds for 31 GeV. Over the ISR energy range, it was found to change insignificantly, (0.8 +/- 1.7)%. The dependences on x_{rm F} and p_{rm t} were measured. The polarization was found to increase with p_{rm t}, and x_{rm F}. At an average p_{rm t} of 1.1 GeV, it was found to depend linearly on x _{rm F}, with approximately -40% at x_{rm F} = 0.8. The |Lambda ^0 polarization was measured, and was found to be 3.8 +/- 1.5%.

  10. PROTON BEAM REQUIREMENTS FOR A NEUTRINO FACTORY AND MUON COLLIDER

    SciTech Connect

    Zisman, Michael S.

    2009-12-11

    Both a Neutrino Factory and a Muon Collider place stringent demands on the proton beam used to generate the desired beam of muons. Here we discuss the advantages and challenges of muon accelerators and the rationale behind the requirements on proton beam energy, intensity, bunch length, and repetition rate. Example proton driver configurations that have been considered in recent years are also briefly indicated.

  11. Experimental validation of beam quality correction factors for proton beams

    NASA Astrophysics Data System (ADS)

    Gomà, Carles; Hofstetter-Boillat, Bénédicte; Safai, Sairos; Vörös, Sándor

    2015-04-01

    This paper presents a method to experimentally validate the beam quality correction factors (kQ) tabulated in IAEA TRS-398 for proton beams and to determine the kQ of non-tabulated ionization chambers (based on the already tabulated values). The method is based exclusively on ionometry and it consists in comparing the reading of two ionization chambers under the same reference conditions in a proton beam quality Q and a reference beam quality 60Co. This allows one to experimentally determine the ratio between the kQ of the two ionization chambers. In this work, 7 different ionization chamber models were irradiated under the IAEA TRS-398 reference conditions for 60Co beams and proton beams. For the latter, the reference conditions for both modulated beams (spread-out Bragg peak field) and monoenergetic beams (pseudo-monoenergetic field) were studied. For monoenergetic beams, it was found that the experimental kQ values obtained for plane-parallel chambers are consistent with the values tabulated in IAEA TRS-398; whereas the kQ values obtained for cylindrical chambers are not consistent—being higher than the tabulated values. These results support the suggestion (of previous publications) that the IAEA TRS-398 reference conditions for monoenergetic proton beams should be revised so that the effective point of measurement of cylindrical ionization chambers is taken into account when positioning the reference point of the chamber at the reference depth. For modulated proton beams, the tabulated kQ values of all the ionization chambers studied in this work were found to be consistent with each other—except for the IBA FC65-G, whose experimental kQ value was found to be 0.6% lower than the tabulated one. The kQ of the PTW Advanced Markus chamber, which is not tabulated in IAEA TRS-398, was found to be 0.997 ± 0.042 (k = 2), based on the tabulated value of the PTW Markus chamber.

  12. J/psi production from proton-proton collisions at square root of s=200 GeV.

    PubMed

    Adler, S S; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Alexander, J; Amirikas, R; Aphecetche, L; Aronson, S H; Averbeck, R; Awes, T C; Azmoun, R; Babintsev, V; Baldisseri, A; Barish, K N; Barnes, P D; Bassalleck, B; Bathe, S; Batsouli, S; Baublis, V; Bazilevsky, A; Belikov, S; Berdnikov, Y; Bhagavatula, S; Boissevain, J G; Borel, H; Borenstein, S; Brooks, M L; Brown, D S; Bruner, N; Bucher, D; Buesching, H; Bumazhnov, V; Bunce, G; Burward-Hoy, J M; Butsyk, S; Camard, X; Chai, J-S; Chand, P; Chang, W C; Chernichenko, S; Chi, C Y; Chiba, J; Chiu, M; Choi, I J; Choi, J; Choudhury, R K; Chujo, T; Cianciolo, V; Cobigo, Y; Cole, B A; Constantin, P; d'Enterria, D G; David, G; Delagrange, H; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Drapier, O; Drees, A; Drees, K A; du Rietz, R; Durum, A; Dutta, D; Efremenko, Y V; El-Chenawi, K; Enokizono, A; En'yo, H; Esumi, S; Ewell, L; Fields, D E; Fleuret, F; Fokin, S L; Fox, B D; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fung, S-Y; Garpman, S; Ghosh, T K; Glenn, A; Gogiberidze, G; Gonin, M; Gosset, J; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grosse Perdekamp, M; Guryn, W; Gustafsson, H-A; Hachiya, T; Haggerty, J S; Hamagaki, H; Hansen, A G; Hartouni, E P; Harvey, M; Hayano, R; He, X; Heffner, M; Hemmick, T K; Heuser, J M; Hibino, M; Hill, J C; Holzmann, W; Homma, K; Hong, B; Hoover, A; Ichihara, T; Ikonnikov, V V; Imai, K; Isenhower, D; Ishihara, M; Issah, M; Isupov, A; Jacak, B V; Jang, W Y; Jeong, Y; Jia, J; Jinnouchi, O; Johnson, B M; Johnson, S C; Joo, K S; Jouan, D; Kametani, S; Kamihara, N; Kang, J H; Kapoor, S S; Katou, K; Kelly, S; Khachaturov, B; Khanzadeev, A; Kikuchi, J; Kim, D H; Kim, D J; Kim, D W; Kim, E; Kim, G-B; Kim, H J; Kistenev, E; Kiyomichi, A; Kiyoyama, K; Klein-Boesing, C; Kobayashi, H; Kochenda, L; Kochetkov, V; Koehler, D; Kohama, T; Kopytine, M; Kotchetkov, D; Kozlov, A; Kroon, P J; Kuberg, C H; Kurita, K; Kuroki, Y; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Ladygin, V; Lajoie, J G; Lebedev, A; Leckey, S; Lee, D M; Lee, S; Leitch, M J; Li, X H; Lim, H; Litvinenko, A; Liu, M X; Liu, Y; Maguire, C F; Makdisi, Y I; Malakhov, A; Manko, V I; Mao, Y; Martinez, G; Marx, M D; Masui, H; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E; Messer, F; Miake, Y; Milan, J; Miller, T E; Milov, A; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Mühlbacher, F; Mukhopadhyay, D; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagle, J L; Nakamura, T; Nandi, B K; Nara, M; Newby, J; Nilsson, P; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Okada, K; Ono, M; Onuchin, V; Oskarsson, A; Otterlund, I; Oyama, K; Ozawa, K; Pal, D; Palounek, A P T; Pantuev, V S; Papavassiliou, V; Park, J; Parmar, A; Pate, S F; Peitzmann, T; Peng, J-C; Peresedov, V; Pinkenburg, C; Pisani, R P; Plasil, F; Purschke, M L; Purwar, A K; Rak, J; Ravinovich, I; Read, K F; Reuter, M; Reygers, K; Riabov, V; Riabov, Y; Roche, G; Romana, A; Rosati, M; Rosnet, P; Ryu, S S; Sadler, M E; Saito, N; Sakaguchi, T; Sakai, M; Sakai, S; Samsonov, V; Sanfratello, L; Santo, R; Sato, H D; Sato, S; Sawada, S; Schutz, Y; Semenov, V; Seto, R; Shaw, M R; Shea, T K; Shibata, T-A; Shigaki, K; Shiina, T; Silva, C L; Silvermyr, D; Sim, K S; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Staley, F; Stankus, P W; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Sugitate, T; Sullivan, J P; Takagui, E M; Taketani, A; Tamai, M; Tanaka, K H; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarján, P; Tepe, J D; Thomas, T L; Tojo, J; Torii, H; Towell, R S; Tserruya, I; Tsuruoka, H; Tuli, S K; Tydesjö, H; Tyurin, N; van Hecke, H W; Velkovska, J; Velkovsky, M; Villatte, L; Vinogradov, A A; Volkov, M A; Vznuzdaev, E; Wang, X R; Watanabe, Y; White, S N; Wohn, F K; Woody, C L; Xie, W; Yang, Y; Yanovich, A; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zhou, S J; Zolin, L

    2004-02-01

    J/psi production has been measured in proton-proton collisions at square root of s=200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at the Relativistic Heavy Ion Collider. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 4.0+/-0.6(stat)+/-0.6(syst)+/-0.4(abs) mu b. The mean transverse momentum is 1.80+/-0.23(stat)+/-0.16(syst) GeV/c. PMID:14995296

  13. Beam-halo measurements in high-current proton beams

    SciTech Connect

    Allen, C.K.; Chan, K.C.D.; Colestock, P.L.; Crandall, K.R.; Garnett, R.W.; Gilpatrick, J.D.; Lysenko, W.; Qiang, J.; Schneider, J.D.; Schulze, M.E.; Sheffield, R.L.; Smith, H.V.; Wangler, T.P.

    2002-01-11

    We present results from an experimental study of the beam halo in a high-current 6.7-MeV proton beam propagating through a 52-quadrupole periodic-focusing channel. The gradients of the first four quadrupoles were independently adjusted to match or mismatch the injected beam. Emittances and beamwidths were obtained from measured profiles for comparisons with maximum emittance-growth predictions of a free-energy model and maximum halo-amplitude predictions of a particle-core model. The experimental results support both models and the present theoretical picture of halo formation.

  14. Applicability of a Bonner Shere technique for pulsed neutron in 120 GeV proton facility

    SciTech Connect

    Sanami, T.; Hagiwara, M.; Iwase, H.; Iwamoto, Y.; Sakamoto, Y.; Nakashima, H.; Arakawa, H.; Shigyo, N.; Leveling, A.F.; Boehnlein, D.J.; Vaziri, K.; /Fermilab

    2008-02-01

    The data on neutron spectra and intensity behind shielding are important for radiation safety design of high-energy accelerators since neutrons are capable of penetrating thick shielding and activating materials. Corresponding particle transport codes--that involve physics models of neutron and other particle production, transportation, and interaction--have been developed and used world-wide [1-8]. The results of these codes have been ensured through plenty of comparisons with experimental results taken in simple geometries. For neutron generation and transport, several related experiments have been performed to measure neutron spectra, attenuation length and reaction rates behind shielding walls of various thicknesses and materials in energy range up to several hundred of MeV [9-11]. The data have been used to benchmark--and modify if needed--the simulation modes and parameters in the codes, as well as the reference data for radiation safety design. To obtain such kind of data above several hundred of MeV, Japan-Fermi National Accelerator Laboratory (FNAL) collaboration for shielding experiments has been started in 2007, based on suggestion from the specialist meeting of shielding, Shielding Aspects of Target, Irradiation Facilities (SATIF), because of very limited data available in high-energy region (see, for example, [12]). As a part of this shielding experiment, a set of Bonner sphere (BS) was tested at the antiproton production target facility (pbar target station) at FNAL to obtain neutron spectra induced by a 120-GeV proton beam in concrete and iron shielding. Generally, utilization of an active detector around high-energy accelerators requires an improvement on its readout to overcome burst of secondary radiation since the accelerator delivers an intense beam to a target in a short period after relatively long acceleration period. In this paper, we employ BS for a spectrum measurement of neutrons that penetrate the shielding wall of the pbar target

  15. Calibration of a proton beam energy monitor

    SciTech Connect

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

    2007-06-15

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

  16. Calibration of a proton beam energy monitor.

    PubMed

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

    2007-06-01

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

  17. Accelerator measurement of the energy spectra of neutrons emitted in the interaction of 3-GeV protons with several elements

    NASA Technical Reports Server (NTRS)

    Nalesnik, W. J.; Devlin, T. J.; Merker, M.; Shen, B. S. P.

    1972-01-01

    The application of time of flight techniques for determining the shapes of the energy spectra of neutrons between 20 and 400 MeV is discussed. The neutrons are emitted at 20, 34, and 90 degrees in the bombardment of targets by 3 GeV protons. The targets used are carbon, aluminum, cobalt, and platinum with cylindrical cross section. Targets being bombarded are located in the internal circulating beam of a particle accelerator.

  18. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    SciTech Connect

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  19. Experimental study of proton beam halo in mismatched beams

    SciTech Connect

    Allen, C. K.; Chan, K. D.; Colestock, P. L. ,; Garnett, R. W.; Gilpatrick, J. D.; Qiang, J.; Lysenko, W. P.; Smith, H. V.; Schneider, J. D.; Sheffield, R. L.; Wangler, Thomas P.,; Schulze, M. E.; Crandall, K. R.

    2002-01-01

    We report measurements of transverse beam-halo formation in mismatched proton beams in a 52-quadrupole FODO-transport channel following the 6.7 MeV RFQ at the Low-Energy Demonstration Accelerator (LEDA) at Los Alamos. Beam profiles in both transverse planes were measured using a new diagnostic device that consists of a movable carbon filament for measurement of the beam core, and scraper plates for measurement of the outer part of the distributions. The initial results indicate a surprisingly strong growth rate of the rms emittance even for the modest space-charge tune depressions of the experiment. Our results are consistent with the complete transfer of free energy of the mismatched beams into emittance growth within 10 envelope oscillations for both the breathing and the quadrupole modes.

  20. Methodology for the neutron time of flight measurement of 120-GeV proton-induced reactions on a thick copper target

    SciTech Connect

    Sanami, T.; Iwamoto, Y.; Kajimoto, T.; Shigyo, N.; Hagiwara, M.; Lee, H. S.; Ramberg, E.; Coleman, R.; Soha, A.; Jensen, D.; Leveling, A.; Mokhov, N. V.; Boehnlein, D.; Vaziri, K.; Ishibashi, K.; Sakamoto, Y.; Nakashima, H.

    2011-12-06

    Our methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 105 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beam events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. Finally our obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.

  1. Methodology for the neutron time of flight measurement of 120-GeV proton-induced reactions on a thick copper target

    NASA Astrophysics Data System (ADS)

    Sanami, T.; Iwamoto, Y.; Kajimoto, T.; Shigyo, N.; Hagiwara, M.; Lee, H. S.; Ramberg, E.; Coleman, R.; Soha, A.; Jensen, D.; Leveling, A.; Mokhov, N. V.; Boehnlein, D.; Vaziri, K.; Ishibashi, K.; Sakamoto, Y.; Nakashima, H.

    2012-03-01

    A methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 105 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beam events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. The obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.

  2. A Precision Measurement of the Proton Strange-Quark Form Factors at Q2 = 0.624 GeV2

    NASA Astrophysics Data System (ADS)

    Friend, Megan Lynn

    The parity-violating asymmetry of the elastic scattering of highly polarized 3.84 GeV electrons from unpolarized protons at Q2 = 0.624 GeV2 has been measured to high precision. The measurement was carried out by the HAPPEX collaboration in Hall A of Jefferson Lab's Continuous Electron Beam Accelerator Facility. This precision measurement required careful control of any potential systematic effects, as well as a very precise determination of the absolute electron-beam polarization. In order to obtain the required precision on the electron-beam polarization measurement, an upgrade of the Hall A Compton polarimeter, and, in particular, the polarimeter's photon-arm detector and data acquisition system, was completed. A parity-violating asymmetry of APV = --23.80 +/- 0.78(stat) +/- 0.36(syst) ppm was measured. The predicted parity-violating asymmetry in the absence of strange quarks is ANS = --24.062 +/- 0.734 ppm. This allows for the extraction of the linear combination of proton strange-quark form factors GsE + 0.517 GsM = 0.003 +/- 0.010(stat) +/- 0.004(syst) +/- 0.009( ANS), where the third error is due to uncertainties in the nucleon electromagnetic form factors and radiative corrections. This measurement is consistent with zero strange contribution to the proton form factors at Q2 = 0.624 GeV2.

  3. Proton beam radiotherapy of iris melanoma

    SciTech Connect

    Damato, Bertil . E-mail: Bertil@damato.co.uk; Kacperek, Andrzej; Chopra, Mona; Sheen, Martin A.; Campbell, Ian R.; Errington, R. Douglas

    2005-09-01

    Purpose: To report on outcomes after proton beam radiotherapy of iris melanoma. Methods and Materials: Between 1993 and 2004, 88 patients with iris melanoma received proton beam radiotherapy, with 53.1 Gy in 4 fractions. Results: The patients had a mean age of 52 years and a median follow-up of 2.7 years. The tumors had a median diameter of 4.3 mm, involving more than 2 clock hours of iris in 32% of patients and more than 2 hours of angle in 27%. The ciliary body was involved in 20%. Cataract was present in 13 patients before treatment and subsequently developed in another 18. Cataract had a 4-year rate of 63% and by Cox analysis was related to age (p = 0.05), initial visual loss (p < 0.0001), iris involvement (p < 0.0001), and tumor thickness (p < 0.0001). Glaucoma was present before treatment in 13 patients and developed after treatment in another 3. Three eyes were enucleated, all because of recurrence, which had an actuarial 4-year rate of 3.3% (95% CI 0-8.0%). Conclusions: Proton beam radiotherapy of iris melanoma is well tolerated, the main problems being radiation-cataract, which was treatable, and preexisting glaucoma, which in several patients was difficult to control.

  4. Mechanical response of proton beam irradiated nitinol

    NASA Astrophysics Data System (ADS)

    Afzal, Naveed; Ghauri, I. M.; Mubarik, F. E.; Amin, F.

    2011-01-01

    The present investigation deals with the study of mechanical behavior of proton beam irradiated nitinol at room temperature. The specimens in austenitic phase were irradiated over periods of 15, 30, 45 and 60 min at room temperature using 2 MeV proton beam obtained from Pelletron accelerator. The stress-strain curves of both unirradiated and irradiated specimens were obtained using a universal testing machine at room temperature. The results of the experiment show that an intermediate rhombohedral (R) phase has been introduced between austenite and martensite phase, which resulted in the suppression of direct transformation from austenite to martensite (A-M). Stresses required to start R-phase ( σRS) and martensitic phase ( σMS) were observed to decrease with increase in exposure time. The hardness tests of samples before and after irradiation were also carried out using Vickers hardness tester. The comparison reveals that the hardness is higher in irradiated specimens than that of the unirradiated one. The increase in hardness is quite sharp in specimens irradiated for 15 min, which then increases linearly as the exposure time is increased up to 60 min. The generation of R-phase, variations in the transformation stresses σRS and σMS and increase in hardness of irradiated nitinol may be attributed to lattice disorder and associated changes in crystal structure induced by proton beam irradiation.

  5. The CMS barrel calorimeter response to particle beams from 2 to 350 GeV/ c

    NASA Astrophysics Data System (ADS)

    Abdullin, S.; Abramov, V.; Acharya, B.; Adam, N.; Adams, M.; Adzic, P.; Akchurin, N.; Akgun, U.; Albayrak, E.; Alemany-Fernandez, R.; Almeida, N.; Anagnostou, G.; Andelin, D.; Anderson, E. W.; Anfreville, M.; Anicin, I.; Antchev, G.; Antunovic, Z.; Arcidiacono, R.; Arenton, M. W.; Auffray, E.; Argiro, S.; Askew, A.; Atramentov, O.; Ayan, S.; Arcidy, M.; Aydin, S.; Aziz, T.; Baarmand, M.; Babich, K.; Baccaro, S.; Baden, D.; Baffioni, S.; Bakirci, M. N.; Balazs, M.; Banerjee, Sud.; Banerjee, Sun.; Bard, R.; Barge, D.; Barnes, V.; Barney, D.; Barone, L.; Bartoloni, A.; Baty, C.; Bawa, H.; Baiatian, G.; Bandurin, D.; Beauceron, S.; Bell, K. W.; Bencze, G.; Benetta, R.; Bercher, M.; Beri, S.; Bernet, C.; Berntzon, L.; Berthon, U.; Besancon, M.; Betev, B.; Beuselinck, R.; Bhatnagar, V.; Bhatti, A.; Biino, C.; Blaha, J.; Bloch, P.; Blyth, S.; Bodek, A.; Bornheim, A.; Bose, S.; Bose, T.; Bourotte, J.; Brett, A. M.; Brown, R. M.; Britton, D.; Budd, H.; Buehler, M.; Burchesky, K.; Busson, P.; Camanzi, B.; Camporesi, T.; Cankoçak, K.; Carrell, K.; Carrera, E.; Cartiglia, N.; Cavallari, F.; Cerci, S.; Cerutti, M.; Chang, P.; Chang, Y. H.; Charlot, C.; Chen, E. A.; Chen, W. T.; Chen, Z.; Chendvankar, S.; Chipaux, R.; Choudhary, B. C.; Choudhury, R. K.; Chung, Y.; Clarida, W.; Cockerill, D. J. A.; Combaret, C.; Conetti, S.; Cossutti, F.; Cox, B.; Cremaldi, L.; Cushman, P.; Cussans, D. G.; Dafinei, I.; Damgov, J.; da Silva di Calafiori, D. R.; Daskalakis, G.; Davatz, G.; David, A.; de Barbaro, P.; Debbins, P.; Deiters, K.; Dejardin, M.; Djordjevic, M.; Deliomeroglu, M.; Della Negra, R.; Della Ricca, G.; Del Re, D.; Demianov, A.; de Min, A.; Denegri, D.; Depasse, P.; de Visser, T.; Descamps, J.; Deshpande, P. V.; Diaz, J.; Diemoz, M.; di Marco, E.; Dimitrov, L.; Dissertori, G.; Dittmar, M.; Djambazov, L.; Dobrzynski, L.; Drndarevic, S.; Duboscq, J. E.; Dugad, S.; Dumanoglu, I.; Duru, F.; Dutta, D.; Dzelalija, M.; Efthymiopoulos, I.; Elias, J.; Elliott-Peisert, A.; El Mamouni, H.; Elvira, D.; Emeliantchik, I.; Eno, S.; Ershov, A.; Erturk, S.; Esen, S.; Eskut, E.; Evangelou, I.; Evans, D. L.; Fabbro, B.; Faure, J. L.; Fay, J.; Fenyvesi, A.; Ferri, F.; Fisher, W.; Flower, P. S.; Franci, D.; Franzoni, G.; Freeman, J.; Freudenreich, K.; Funk, W.; Ganjour, S.; Gargiulo, C.; Gascon, S.; Gataullin, M.; Gaultney, V.; Gamsizkan, H.; Gavrilov, V.; Geerebaert, Y.; Genchev, V.; Gentit, F. X.; Gerbaudo, D.; Gershtein, Y.; Ghezzi, A.; Ghodgaonkar, M. D.; Gilly, J.; Givernaud, A.; Gleyzer, S.; Gninenko, S.; Go, A.; Gobbo, B.; Godinovic, N.; Golubev, N.; Golutvin, I.; Goncharov, P.; Gong, D.; Govoni, P.; Grant, N.; Gras, P.; Grassi, T.; Green, D.; Greenhalgh, R. J. S.; Gribushin, A.; Grinev, B.; Guevara Riveros, L.; Guillaud, J. P.; Gurtu, A.; Murat Güler, A.; Gülmez, E.; Gümüş, K.; Haelen, T.; Hagopian, S.; Hagopian, V.; Haguenauer, M.; Halyo, V.; Hamel de Monchenault, G.; Hansen, M.; Hashemi, M.; Hauptman, J.; Hazen, E.; Heath, H. F.; Heering, A.; Heister, A.; Heltsley, B.; Hill, J. A.; Hintz, W.; Hirosky, R.; Hobson, P. R.; Honma, A.; Hou, G. W. S.; Hsiung, Y.; Hunt, A.; Husejko, M.; Ille, B.; Ilyina, N.; Imlay, R.; Ingram, D.; Ingram, Q.; Isiksal, E.; Jarry, P.; Jarvis, C.; Jeong, C.; Jessop, C.; Johnson, K.; Jones, J.; Jovanovic, D.; Kaadze, K.; Kachanov, V.; Kaftanov, V.; Kailas, S.; Kalagin, V.; Kalinin, A.; Kalmani, S.; Karmgard, D.; Kataria, S. K.; Kaur, M.; Kaya, M.; Kaya, O.; Kayis-Topaksu, A.; Kellogg, R.; Kennedy, B. W.; Khmelnikov, A.; Kim, H.; Kisselevich, I.; Kloukinas, K.; Kodolova, O.; Kohli, J.; Kokkas, P.; Kolberg, T.; Kolossov, V.; Korablev, A.; Korneev, Y.; Kosarev, I.; Kramer, L.; Krasnikov, N.; Krinitsyn, A.; Krokhotin, A.; Krpic, D.; Kryshkin, V.; Kubota, Y.; Kubrik, A.; Kuleshov, S.; Kumar, A.; Kumar, P.; Kunori, S.; Kuo, C. M.; Kurt, P.; Kyberd, P.; Kyriakis, A.; Laasanen, A.; Ladygin, V.; Laird, E.; Landsberg, G.; Laszlo, A.; Lawlor, C.; Lazic, D.; Lebeau, M.; Lecomte, P.; Lecoq, P.; Ledovskoy, A.; Lee, S.-W.; Leshev, G.; Lethuillier, M.; Levchuk, L.; Lin, S. W.; Lin, W.; Linn, S.; Lintern, A. L.; Litvine, V.; Litvintsev, D.; Litov, L.; Lobolo, L.; Locci, E.; Lodge, A. B.; Longo, E.; Loukas, D.; Los, S.; Lubinsky, V.; Luckey, P. D.; Lukanin, V.; Lustermann, W.; Lynch, C.; Ma, Y.; Machado, E.; Mahlke-Krueger, H.; Maity, M.; Majumder, G.; Malberti, M.; Malclès, J.; Maletic, D.; Mandjavidze, I.; Mans, J.; Manthos, N.; Maravin, Y.; Marchica, C.; Marinelli, N.; Markou, A.; Markou, C.; Marlow, D.; Markowitz, P.; Marone, M.; Martinez, G.; Mathez, H.; Matveev, V.; Mavrommatis, C.; Maurelli, G.; Mazumdar, K.; Meridiani, P.; Merlo, J. P.; Mermerkaya, H.; Mescheryakov, G.; Mestvirishvili, A.; Mikhailin, V.; Milenovic, P.; Miller, M.; Milleret, G.; Miné, P.; Moeller, A.; Mohammadi-Najafabadi, M.; Mohanty, A. K.; Moissenz, P.

    2009-04-01

    The response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/ c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter response to charged pions, kaons, protons and antiprotons and a detailed discussion of the underlying phenomena are presented. We also show techniques that apply corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) barrel calorimeters in reconstructing the energies of hadrons. Above 5 GeV/ c, these corrections improve the energy resolution of the combined system where the stochastic term equals 84.7±1.6% and the constant term is 7.4±0.8%. The corrected mean response remains constant within 1.3% rms.

  6. Late effects of 2.2 GeV protons on the central nervous system.

    NASA Technical Reports Server (NTRS)

    Lippincott, S. W.; Calvo, W.

    1971-01-01

    Investigation of late pathological effects of high-energy (2.2 GeV) protons on the brain of rabbits, in a postirradiation period of up to 16 months following exposure at fluxes of 30, 100, and 1000 billion protons per sq cm. At the latter two irradiation-intensity levels, the kinds of brain lesions inflicted include large venous dilatation, thickening of vessel walls with deposit of amorphous PAS positive substance, thrombosis, perivascular infiltration of leukocytes and macrophages, mobilization of microglia cells, gliosis, demyelinization, and multiple small pseudocyst formation.

  7. Methodology for the neutron time of flight measurement of 120-GeV proton-induced reactions on a thick copper target

    DOE PAGESBeta

    Sanami, T.; Iwamoto, Y.; Kajimoto, T.; Shigyo, N.; Hagiwara, M.; Lee, H. S.; Ramberg, E.; Coleman, R.; Soha, A.; Jensen, D.; et al

    2011-12-06

    Our methodology for the time-of-flight measurement of the neutron energy spectrum for a high-energy proton-beam-induced reaction was established at the Fermilab Test Beam Facility of the Fermi National Accelerator Laboratory. The 120-GeV proton beam with 3 × 105 protons/spill was prepared for event-by-event counting of incident protons and emitted neutrons for time-of-flight energy determination. An NE213 organic liquid scintillator (12.7 cm in diameter by 12.7 cm in length) was employed with a veto plastic scintillator and a pulse-shape discrimination technique to identify neutrons. Raw waveforms of NE213, veto and beam detectors were recorded to discriminate the effects of multi-proton beammore » events by considering different time windows. The neutron energy spectrum ranging from 10 to 800 MeV was obtained for a 60-cm-long copper target at 90° with respect to the beam axis. Finally our obtained spectrum was consistent with that deduced employing the conventional unfolding technique as well as that obtained in a 40-GeV/c thin-target experiment.« less

  8. 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

  9. Energy spectrum control for modulated proton beams.

    PubMed

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

    2009-06-01

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to +/-21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than +/-3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies. PMID:19610318

  10. Energy spectrum control for modulated proton beams

    SciTech Connect

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

    2009-06-15

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

  11. Proton-Beam Therapy for Olfactory Neuroblastoma

    SciTech Connect

    Nishimura, Hideki . E-mail: westvill@med.kobe-u.ac.jp; Ogino, Takashi; Kawashima, Mitsuhiko; Nihei, Keiji; Arahira, Satoko; Onozawa, Masakatsu; Katsuta, Shoichi; Nishio, Teiji

    2007-07-01

    Purpose: To analyze the feasibility and efficacy of proton-beam therapy (PBT) for olfactory neuroblastoma (ONB) as a definitive treatment, by reviewing our preliminary experience. Olfactory neuroblastoma is a rare disease, and a standard treatment strategy has not been established. Radiation therapy for ONB is challenging because of the proximity of ONBs to critical organs. Proton-beam therapy can provide better dose distribution compared with X-ray irradiation because of its physical characteristics, and is deemed to be a feasible treatment modality. Methods and Materials: A retrospective review was performed on 14 patients who underwent PBT for ONB as definitive treatment at the National Cancer Center Hospital East (Kashiwa, Chiba, Japan) from November 1999 to February 2005. A total dose of PBT was 65 cobalt Gray equivalents (Gy{sub E}), with 2.5-Gy{sub E} once-daily fractionations. Results: The median follow-up period for surviving patients was 40 months. One patient died from disseminated disease. There were two persistent diseases, one of which was successfully salvaged with surgery. The 5-year overall survival rate was 93%, the 5-year local progression-free survival rate was 84%, and the 5-year relapse-free survival rate was 71%. Liquorrhea was observed in one patient with Kadish's stage C disease (widely destroying the skull base). Most patients experienced Grade 1 to 2 dermatitis in the acute phase. No other adverse events of Grade 3 or greater were observed according to the RTOG/EORTC acute and late morbidity scoring system. Conclusions: Our preliminary results of PBT for ONB achieved excellent local control and survival outcomes without serious adverse effects. Proton-beam therapy is considered a safe and effective modality that warrants further study.

  12. Neutron yield and induced radioactivity: a study of 235-MeV proton and 3-GeV electron accelerators.

    PubMed

    Hsu, Yung-Cheng; Lai, Bo-Lun; Sheu, Rong-Jiun

    2016-01-01

    This study evaluated the magnitude of potential neutron yield and induced radioactivity of two new accelerators in Taiwan: a 235-MeV proton cyclotron for radiation therapy and a 3-GeV electron synchrotron serving as the injector for the Taiwan Photon Source. From a nuclear interaction point of view, neutron production from targets bombarded with high-energy particles is intrinsically related to the resulting target activation. Two multi-particle interaction and transport codes, FLUKA and MCNPX, were used in this study. To ensure prediction quality, much effort was devoted to the associated benchmark calculations. Comparisons of the accelerators' results for three target materials (copper, stainless steel and tissue) are presented. Although the proton-induced neutron yields were higher than those induced by electrons, the maximal neutron production rates of both accelerators were comparable according to their respective beam outputs during typical operation. Activation products in the targets of the two accelerators were unexpectedly similar because the primary reaction channels for proton- and electron-induced activation are (p,pn) and (γ,n), respectively. The resulting residual activities and remnant dose rates as a function of time were examined and discussed. PMID:25628454

  13. 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%.

  14. 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

  15. Indirect self-modulation instability measurement concept for the AWAKE proton beam

    NASA Astrophysics Data System (ADS)

    Turner, M.; Petrenko, A.; Biskup, B.; Burger, S.; Gschwendtner, E.; Lotov, K. V.; Mazzoni, S.; Vincke, H.

    2016-09-01

    AWAKE, the Advanced Proton-Driven Plasma Wakefield Acceleration Experiment, is a proof-of-principle R&D experiment at CERN using a 400 GeV / c proton beam from the CERN SPS (longitudinal beam size σz = 12 cm) which will be sent into a 10 m long plasma section with a nominal density of ≈ 7 ×1014 atoms /cm3 (plasma wavelength λp = 1.2 mm). In this paper we show that by measuring the time integrated transverse profile of the proton bunch at two locations downstream of the AWAKE plasma, information about the occurrence of the self-modulation instability (SMI) can be inferred. In particular we show that measuring defocused protons with an angle of 1 mrad corresponds to having electric fields in the order of GV/m and fully developed self-modulation of the proton bunch. Additionally, by measuring the defocused beam edge of the self-modulated bunch, information about the growth rate of the instability can be extracted. If hosing instability occurs, it could be detected by measuring a non-uniform defocused beam shape with changing radius. Using a 1 mm thick Chromox scintillation screen for imaging of the self-modulated proton bunch, an edge resolution of 0.6 mm and hence an SMI saturation point resolution of 1.2 m can be achieved.

  16. The second generation Singapore high resolution proton beam writing facilitya)

    NASA Astrophysics Data System (ADS)

    van Kan, J. A.; Malar, P.; Baysic de Vera, Armin

    2012-02-01

    A new proton beam focusing facility, designed for proton beam writing (PBW) applications has been tested. PBW allows for proximity free structuring of high aspect ratio, high-density 3D nanostructures. The new facility is designed around OM52 compact quadrupole lenses capable of operating in a variety of high demagnification configurations. Performance tests show that proton beams can be focused down to 19.0 × 29.9 nm2 and single line scans show a beam width of 12.6 nm. The ultimate goal of sub 10 nm structuring with MeV protons will be discussed.

  17. Early Commissioning Experience and Future Plans for the 12 GeV Continuous Electron Beam Accelerator Facility

    SciTech Connect

    Spata, Michael F.

    2014-12-01

    Jefferson Lab has recently completed the accelerator portion of the 12 GeV Upgrade for the Continuous Electron Beam Accelerator Facility. All 52 SRF cryomodules have been commissioned and operated with beam. The initial beam transport goals of demonstrating 2.2 GeV per pass, greater than 6 GeV in 3 passes to an existing experimental facility and greater than 10 GeV in 5-1/2 passes have all been accomplished. These results along with future plans to commission the remaining beamlines and to increase the performance of the accelerator to achieve reliable, robust and efficient operations at 12 GeV are presented.

  18. CRYSTALLINE CHROMIUM DOPED ALUMINUM OXIDE (RUBY) USE AS A LUMINESCENT SCREEN FOR PROTON BEAMS.

    SciTech Connect

    BROWN,K.A.; GASSNER,D.M.

    1999-03-29

    In our search for a better luminescent screen material, we tested pieces of mono-crystalline chromium doped aluminum oxide (more commonly known as a ruby) using a 24 GeV proton beam. Due to the large variations in beam intensity and species which are run at the Alternating Gradient Synchrotron (AGS), we hope to find a material which can sufficiently luminesce, is compatible in vacuum, and maintain its performance level over extended use. Results from frame grabbed video camera images using a variety of neutral density filters are presented.

  19. Transverse beam shape measurements of intense proton beams using optical transition radiation

    SciTech Connect

    Scarpine, Victor E.; /Fermilab

    2012-03-01

    A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.

  20. Proton-beam therapy for prostate cancer.

    PubMed

    Kagan, A Robert; Schulz, Robert J

    2010-01-01

    The treatment options for prostate cancer include prostatectomy, external-beam irradiation, brachytherapy, cryosurgery, focused ultrasound, hormonal therapy, watchful waiting, and various combinations of these modalities. Because the prostate abuts the bladder and rectum, the dose distributions of external-beam irradiations and the accuracy of their placement play crucial roles in the probability of tumor cure and the incidence of posttreatment complications. Principal among the newer radiation technologies is proton-beam therapy (PBT), whose dose distributions make it possible to deliver higher tumor doses and smaller doses to surrounding normal tissues than from x-ray systems. However, as the 10-year cause-specific survival for early-stage disease treated by radiation therapy now exceeds 90%, and with severe late toxicities in the range of 2% to 3%, randomized clinical trials provide the only means to demonstrate improved outcomes from PBT. Short of the data provided by such trials, the efficacy of PBT can be gleaned only from reports in the clinical literature, and, to date, these reports are equivocal. In view of the current health care crisis and the higher costs of PBT for prostate cancer, it is reasonable to assess the viability of this in-vogue but not-so-new technology. PMID:20890135

  1. RHIC Performance as a 100 GeV Polarized Proton Collider in Run-9

    SciTech Connect

    Montag, C.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; DOttavio, T.; Drees, A.; Fedotov, A.V.; Fischer, W.; Ganetis, G.; Gardner, C.; Glenn, J.; Hahn, H.; Harvey, M.; Hayes, T.; Huang, H.; Ingrassia, P.; Jamilkowski, J.; Kayran, D.; Kewisch, J.; Lee, R.C.; Luccio, A.U.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Malitsky, N.; Marr, G.; Marusic, A.; Menga, P.M.; Michnoff, R.; Minty, M.; Morris, J.; Oerter, B.; Pilat, F.; Pile, P.; Pozdeyev, E.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Russo, T.; Satogata, T.; Schoefer, V.; Schultheiss, C.; Severino, F.; Sivertz, M.; Smith, K.; Tepikian, S.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2010-05-23

    During the second half of Run-9, the Relativisitc Heavy Ion Collider (RHIC) provided polarized proton collisions at two interaction points. The spin orientation of both beams at these collision points was controlled by helical spin rotators, and physics data were taken with different orientations of the beam polarization. Recent developments and improvements will be presented, as well as luminosity and polarization performance achieved during Run-9.

  2. Polarization of Ω- hyperons produced in 800 GeV proton-beryllium collisions

    NASA Astrophysics Data System (ADS)

    Luk, K. B.; James, C.; Rameika, R.; Diehl, H. T.; Teige, S.; Thomson, G. B.; Zou, Y.; Ho, P. M.; Longo, M. J.; Nguyen, A.; Duryea, J.; Guglielmo, G.; Heller, K.; Johns, K.; Thorne, K.

    1993-02-01

    The polarization of 103 211 Ω- hyperons produced in 800 GeV proton-beryllium inclusive reactions has been measured. Between 0.3=0.5 and =0.95 GeV/c. This behavior is similar to that of Λ¯0, which also does not have any quarks in common with the incident proton, but is different from Ξ¯+, which is significantly polarized in the same kinematic region.

  3. Generation of GeV protons from 1 PW laser interaction with near critical density targets

    PubMed Central

    Bulanov, Stepan S.; Bychenkov, Valery Yu.; Chvykov, Vladimir; Kalinchenko, Galina; Litzenberg, Dale William; Matsuoka, Takeshi; Thomas, Alexander G. R.; Willingale, Louise; Yanovsky, Victor; Krushelnick, Karl; Maksimchuk, Anatoly

    2010-01-01

    The propagation of ultraintense laser pulses through matter is connected with the generation of strong moving magnetic fields in the propagation channel as well as the formation of a thin ion filament along the axis of the channel. Upon exiting the plasma the magnetic field displaces the electrons at the back of the target, generating a quasistatic electric field that accelerates and collimates ions from the filament. Two dimensional particle-in-cell simulations show that a 1 PW laser pulse tightly focused on a near-critical density target is able to accelerate protons up to an energy of 1.3 GeV. Scaling laws and optimal conditions for proton acceleration are established considering the energy depletion of the laser pulse. PMID:20838426

  4. Pion Production from 5-15 GeV Beam for the Neutrino Factory Front-End Study

    SciTech Connect

    Prior, Gersende

    2010-03-30

    For the neutrino factory front-end study, the production of pions from a proton beam of 5-8 and 14 GeV kinetic energy on a Hg jet target has been simulated. The pion yields for two versions of the MARS15 code and two different field configurations have been compared. The particles have also been tracked from the target position down to the end of the cooling channel using the ICOOL code and the neutrino factory baseline lattice. The momentum-angle region of pions producing muons that survived until the end of the cooling channel has been compared with the region covered by HARP data and the number of pions/muons as a function of the incoming beam energy is also reported.

  5. Formation of Hot Nuclei with GeV {ital p} and {ital {pi}}{sup {minus}} Beams

    SciTech Connect

    Hsi, W.; Kwiatkowski, K.; Wang, G.; Bracken, D.S.; Cornell, E.; Ginger, D.S.; Viola, V.E.; Yoder, N.R.; Korteling, R.G.; Gimeno-Nogures, F.; Ramakrishnan, E.; Rowland, D.; Yennello, S.J.; Huang, M.J.; Lynch, W.G.; Tsang, M.B.; Xi, H.; Chu, Y.Y.; Gushue, S.; Remsberg, L.P.; Morley, K.B.; Breuer, H.

    1997-08-01

    4{pi} studies of multiple charged-particle emission in GeV {pi}{sup {minus}} - and proton-induced reactions on a Au target have been performed with the ISiS detector array. Multiplicity, charge, and angular distributions yield nearly identical results for both p and {pi}{sup {minus}} beams, suggesting an independence of hadron type in initiating the fast cascade and subsequent energy deposition in the struck nucleus. The excitation functions show little sensitivity to beam momentum, consistent with a saturation in deposition energy and the concept of limiting fragmentation. However, the intermediate mass fragment multiplicities and fragment charge distributions depend strongly on collision violence. {copyright} {ital 1997} {ital The American Physical Society}

  6. GeV electron beams from a centimeter-scale laser-driven plasmaaccelerator

    SciTech Connect

    Gonsalves, A.; Nakamura, K.; Panasenko, D.; Toth, Cs.; Esarey,E.; Schroeder; Hooker, S.M.; and Leemans, W.P.; Hooker, S.M.

    2007-06-25

    esults are presented on the generation ofquasi-monoenergeticelectron beams with energy up to 1GeV using a 40TWlaser and a 3.3 cm-long hydrogen-filled capillary discharge waveguide.Electron beams were not observed without a plasma channel, indicatingthat self-focusing alone could not be relied upon for effective guidingofthe laser pulse. Results are presented of the electronbeam spectra, andthe dependence of the reliability of producingelectron beams as afunction of laser and plasma parameters.

  7. Heavy ion linac as a high current proton beam injector

    NASA Astrophysics Data System (ADS)

    Barth, Winfried; Adonin, Aleksey; Appel, Sabrina; Gerhard, Peter; Heilmann, Manuel; Heymach, Frank; Hollinger, Ralph; Vinzenz, Wolfgang; Vormann, Hartmut; Yaramyshev, Stepan

    2015-05-01

    A significant part of the experimental program at Facility for Antiproton and Ion Research (FAIR) is dedicated to pbar physics requiring a high number of cooled pbars per hour. The primary proton beam has to be provided by a 70 MeV proton linac followed by two synchrotrons. The new FAIR proton linac will deliver a pulsed proton beam of up to 35 mA of 36 μ s duration at a repetition rate of 4 Hz (maximum). The GSI heavy ion linac (UNILAC) is able to deliver world record uranium beam intensities for injection into the synchrotrons, but it is not suitable for FAIR relevant proton beam operation. In an advanced machine investigation program it could be shown that the UNILAC is able to provide for sufficient high intensities of CH3 beam, cracked (and stripped) in a supersonic nitrogen gas jet into protons and carbon ions. This advanced operational approach will result in up to 3 mA of proton intensity at a maximum beam energy of 20 MeV, 1 0 0 μ s pulse duration and a repetition rate of up to 2.7 Hz delivered to the synchrotron SIS18. Recent linac beam measurements will be presented, showing that the UNILAC is able to serve as a proton FAIR injector for the first time, while the performance is limited to 25% of the FAIR requirements.

  8. A Polarimeter for GeV Linearly-polarized Photon Beams

    NASA Astrophysics Data System (ADS)

    Wood, M. H.; Tedeschi, D.; Wojtsekhowski, B.; Abbott, D.; Nelyubin, V.; Vlahovic, B.; Asai, J.; Feldman, G.; O'Rielly, G.; Khandaker, Mahbub; Hotta, T.; Kohri, H.; Matsumura, T.; Mibe, T.; Nakano, T.; Yorita, T.; Rudge, A.; Weilhammer, P.; Zegers, R.

    2003-04-01

    We have built a polarimeter for linearly-polarized photon beams in the few GeV photon-energy range. The technique is to detect an electron-positron pair produced from a photon incident on a thin converter. The orientation and the distance separating the e^+ and e^- are measured accurately with silicon-microstrip detectors. The polarimeter was calibrated at the SPring-8 facility using a compton-backscattered photon beam in the energy range of 1.5 GeV ≤ E_γ ≤ 2.4 GeV. This measurement was the first made for the process at these energies. Results will be presented of the measured asymmetry between horizontally and vertically polarized beams.

  9. Investigation of the p+N {yields} [{Sigma}{sup 0}K{sup +}]+N reaction at the proton energy E{sub p} = 70 GeV

    SciTech Connect

    1994-08-01

    The p+N {yields} [{Sigma}{sup 0}K{sup +}]+N reaction was studied in experiments using the SPHINX detector placed in the 70-GeV proton beam of the IHEP accelerator. In the effective mass spectrum of the M({Sigma}{sup 0}K{sup +}) system produced in the coherent diffractive transition, a clear peak with mass M = 1999 {+-} 7 MeV and width {Gamma} = 91 {+-} 17 MeV was observed in addition to the near-threshold structure with mass M {approx_equal} 1800 MeV. 7 refs., 3 figs.

  10. eta-prime photoproduction on the proton for photon energies from 1.527 to 2.227 GeV

    SciTech Connect

    M. Dugger; J. P. Ball; P. Collins; E. Pasyuk; B. G. Ritchie

    2006-01-13

    Differential cross sections for the reaction gamma p {yields} eta-prime p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data indicate for the first time the coupling of the eta prime N channel to both the S{sub 11}(1535) and P{sub 11}(1710) resonances, known to couple strongly to the eta N channel in photoproduction on the proton, and the importance of j=3/2 resonances in the process.

  11. Dose conformation of intensity-modulated stereotactic photon beams, proton beams, and intensity-modulated proton beams for intracranial lesions

    SciTech Connect

    Baumert, Brigitta G. . E-mail: brigitta.baumert@maastro.nl; Norton, Ian A.; Lomax, Antony J.; Davis, J.B.

    2004-11-15

    Purpose: This study evaluates photon beam intensity-modulated stereotactic radiotherapy (IMSRT) based on dynamic leaf motion of a micromultileaf collimator (mMLC), proton beams, and intensity-modulated proton therapy (IMPT) with respect to target coverage and organs at risk. Methods and materials: Dose plans of 6 stereotactically treated patients were recalculated for IMSRT by use of the same field setup and an inverse planning algorithm. Proton and IMPT plans were calculated anew. Three different tumor shapes, multifocal, ovoid, and irregular, were analyzed, as well as dose to organs-at-risk (OAR) in the vicinity of the planning target volume (PTV). Dose distributions were calculated from beam-setup data for a manual mMLC for stereotactically guided conformal radiotherapy (SCRT), a dynamic mMLC for IMSRT, the spot-scanning technique for protons, and a modified spot-scanning technique for IMPT. SCRT was included for a part of the comparison. Criteria for assessment were PTV coverage, dose-volume histograms (DVH), volumes of specific isodoses, and the dose to OAR. Results: Dose conformation to the PTV is equally good for all three techniques and tumor shapes considered. The volumes of the 90% and 80% isodose were comparable for all techniques. For the 50% isodose volume, a divergence between the two modes was seen. In 3 cases, this volume is smaller for IMSRT, and in the 3 other cases, it is smaller for IMPT. This difference was even more pronounced for the volumes of the 30% isodose; IMPT shows further improvement over conventional protons. OAR in concavities (e.g., the brainstem) were similarly well spared by protons and IMSRT. IMPT spares critical organs best. Fewer proton beams are required to achieve similar results. Conclusions: The addition of intensity modulation improves the conformality of mMLC-based SCRT. Conformation of dose to the PTV is comparable for IMSRT, protons, and IMPT. Concerning the sparing of OAR, IMSRT is equivalent to IMPT, and IMPT is

  12. Determination of the beam-spin asymmetry of deuteron photodisintegration in the energy region Eγ=1.1 -2.3 GeV

    NASA Astrophysics Data System (ADS)

    Zachariou, N.; Ilieva, Y.; Berman, B. L.; Ivanov, N. Ya.; Sargsian, M. M.; Avakian, R.; Feldman, G.; Nadel-Turonski, P.; Adhikari, K. P.; Adikaram, D.; Anderson, M. D.; Pereira, S. Anefalos; Avakian, H.; Badui, R. A.; Baltzell, N. A.; Battaglieri, M.; Baturin, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Glazier, D. I.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Kubarovsky, V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mattione, P. T.; McKinnon, B.; Mineeva, T.; Mirazita, M.; Mokeeev, V. I.; Montgomery, R. A.; Moutarde, H.; Camacho, C. Munoz; Net, L. A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Senderovich, I.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D.; Wei, X.; Wood, M. H.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2015-05-01

    The beam-spin asymmetry, Σ , for the reaction γ d →p n has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab) for six photon-energy bins, between 1.1 and 2.3 GeV, and proton angles in the center-of-mass frame, θc .m ., between 25∘ and 160∘. These are the first measurements of beam-spin asymmetries at θc .m .=90∘ for photon-beam energies above 1.6 GeV, and the first measurements for angles other than θc .m .=90∘ . The angular and energy dependence of Σ is expected to aid in the development of QCD-based models to understand the mechanisms of deuteron photodisintegration in the transition region between hadronic and partonic degrees of freedom, where both effective field theories and perturbative QCD cannot make reliable predictions.

  13. Transverse Beam Spin Asymmetries at Backward Angles in Elastic Electron-Proton and Quasielastic Electron-Deuteron Scattering

    NASA Astrophysics Data System (ADS)

    Androić, D.; Armstrong, D. S.; Arvieux, J.; Bailey, S. L.; Beck, D. H.; Beise, E. J.; Benesch, J.; Benmokhtar, F.; Bimbot, L.; Birchall, J.; Bosted, P.; Breuer, H.; Capuano, C. L.; Chao, Y.-C.; Coppens, A.; Davis, C. A.; Ellis, C.; Flores, G.; Franklin, G.; Furget, C.; Gaskell, D.; Gericke, M. T. W.; Grames, J.; Guillard, G.; Hansknecht, J.; Horn, T.; Jones, M. K.; King, P. M.; Korsch, W.; Kox, S.; Lee, L.; Liu, J.; Lung, A.; Mammei, J.; Martin, J. W.; McKeown, R. D.; Micherdzinska, A.; Mihovilovic, M.; Mkrtchyan, H.; Muether, M.; Page, S. A.; Papavassiliou, V.; Pate, S. F.; Phillips, S. K.; Pillot, P.; Pitt, M. L.; Poelker, M.; Quinn, B.; Ramsay, W. D.; Real, J.-S.; Roche, J.; Roos, P.; Schaub, J.; Seva, T.; Simicevic, N.; Smith, G. R.; Spayde, D. T.; Stutzman, M.; Suleiman, R.; Tadevosyan, V.; van Oers, W. T. H.; Versteegen, M.; Voutier, E.; Vulcan, W.; Wells, S. P.; Williamson, S. E.; Wood, S. A.; Pasquini, B.; Vanderhaeghen, M.

    2011-07-01

    We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108°) for Q2=0.22GeV2/c2 and 0.63GeV2/c2 at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (πN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.

  14. Polarization Transfer Coefficient Measurements in the Deuteron Breakup Reaction HYDROGEN-1(POLARIZED Deuteron, Polarized Proton)x at 2.1 GEV.

    NASA Astrophysics Data System (ADS)

    Cheung, Naipor Eric

    The polarization of the protons emerging at 0 ^circ from the inclusive deuteron breakup reaction ^1H(vec d,vec p)X was measured using a deuteron beam with kinetic energy of 2.1 GeV. The momentum of the protons was selected by the magnetic spectrometer SPES4 and the polarization was measured with the polarimeter POMME. This experiment was performed at eight different proton momenta. When those momenta are Lorentz transformed to the deuteron rest frame, they corresponded to values from 0.00 to 0.34 GeV/c. The result of the measurements is expressed in terms of polarization transfer coefficient which is defined as the ratio of the measured proton polarization P_{p} to the deuteron beam vector polarization P _{Z}:kappa_{o} = P_{p}/P_{Z}. The values of kappa_{o} decreased from 0.995 to -0.320 across the proton momentum range of this experiment. The trend of kappa_{o} is in general agreement with the expected behavior arising from the D state in the deuteron wave function. The impulse approximation predicts quite well the general shape of kappa_{o}. Multiple scattering and relativistic effect based on different models of reaction mechanism are discussed.

  15. Eta photoproduction on the proton for photon energies from 0.75 to 1.95 GeV.

    PubMed

    Dugger, M; Ritchie, B G; Ball, J; Pasyuk, E; Adams, G; Anciant, E; Anghinolfi, M; Asavapibhop, B; Audit, G; Auger, T; Avakian, H; Bagdasaryan, H; Barrow, S; Battaglieri, M; Beard, K; Bektasoglu, M; Bellis, M; Berman, B L; Bianchi, N; Biselli, A S; Boiarinov, S; Bouchigny, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Calarco, J R; Capitani, G P; Carman, D S; Carnahan, B; Cetina, C; Clark, R; Cole, P L; Coleman, A; Connelly, J; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J P; DeSanctis, E; DeVita, R; Degtyarenko, P V; Denizli, H; Dennis, L; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Doughty, D; Dragovitsch, P; Dytman, S; Eckhause, M; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Farhi, L; Fatemi, R; Feldman, G; Feuerbach, R J; Ficenec, J; Forest, T A; Frolov, V; Funsten, H; Gaff, S J; Gai, M; Gavalian, G; Gilad, S; Gilfoyle, G P; Giovanetti, K L; Girard, P; Gordon, C I O; Griffioen, K; Guidal, M; Guillo, M; Guo, L; Gyurjyan, V; Hadjidakis, C; Hancock, D; Hardie, J; Heddle, D; Heimberg, P; Hersman, F W; Hicks, K; Hicks, R S; Holtrop, M; Hyde-Wright, C E; Ito, M M; Jenkins, D; Joo, K; Kelley, J H; Kellie, J D; Khandaker, M; Kim, W; Klein, A; Klein, F J; Klusman, M; Kossov, M; Koubarovski, V; Kramer, L H; Kuang, Y; Kuhn, S E; Kuhn, J; Lachniet, J; Laget, J M; Lawrence, D; Li, Ji; Livingston, K; Longhi, A; Lucas, M; Lukashin, K; Major, W; Manak, J J; Marchand, C; McAleer, S; McCarthy, J; McNabb, J W C; Mecking, B A; Mehrabyan, S; Mestayer, M D; Meyer, C A; Mikhailov, K; Minehart, R; Mirazita, M; Miskimen, R; Morand, L; Morrow, S A; Mozer, M U; Muccifora, V; Mueller, J; Murphy, L Y; Mutchler, G S; Napolitano, J; Nasseripour, R; Nelson, S O; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Brien, J T; O'Rielly, G V; Opper, A K; Park, K; Peterson, G; Philips, S A; Pivnyuk, N; Pocanić, D; Pogorelko, O; Polli, E; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ronchetti, F; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Sabourov, K; Salgado, C; Santoro, J P; Sanzone-Arenhovel, M; Sapunenko, V; Schumacher, R A; Serov, V S; Shafi, A; Sharabian, Y G; Shaw, J; Skabelin, A V; Smith, E S; Smith, T; Smith, L C; Sober, D I; Spraker, M; Stavinsky, A; Stepanyan, S; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Taylor, S; Tedeschi, D J; Thoma, U; Thompson, R; Todor, L; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weller, H; Weygand, D P; Whisnant, C S; Witkowski, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zhang, B; Zhao, J; Zhou, Z

    2002-11-25

    Differential cross sections for gammap-->etap have been measured with tagged real photons for incident photon energies from 0.75 to 1.95 GeV. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the production process. The data provide the first extensive angular distribution measurements for the process above W=1.75 GeV. Comparison with preliminary results from a constituent quark model support the suggestion that a third S11 resonance with mass approximately 1.8 GeV couples to the etaN channel. PMID:12485062

  16. Measurement of spin parameters in inclusive. Lambda. and K sub S production using a polarized proton beam

    SciTech Connect

    Tonse, S.R.

    1988-01-01

    A polarized proton beam incident on a Beryllium target was used for inclusive {Lambda}(1116 meV) production at beam momenta of 13.3 GeV and 18.5 GeV. The beam polarization was transverse to the beam direction with magnitude 0.63(0.40) at 13.3(18.5) GeV. The trigger condition favored forward produced {Lambda}'s with moderately high p{sub T}(p{sub T} {approximately} 1GeV). The {Lambda} polarization was measured and found to be in agreement with results from earlier experiments which used unpolarized proton beams. Analyzing power (A) and depolarization (D{sub NN}) of the {Lambda}'s were both measured and compared with a hyperon polarization model in which the polarization arises from a Thomas precession effect. There is good agreement with its predictions: A = 0 and D{sub NN} = 0. In particular, our measurement of D{sub NN} = {minus}0.009 {plus minus} 0.015 supports the idea that the valence quarks carry all of the hadron spin, since this assumption is implicit in the model's use of SU(6) wave functions to form final state hadrons from beam fragments and sea quarks. The analyzing power of K{sub s} was also measured at 13.3(18.5)GeV and found to be {minus}0.094 {plus minus} 0.012 ({minus}0.076 {plus minus} 0.015). We use the same model to predict A of K{sub s}, taking into account K{sub s} production from various sources (K{degree}, K{degree} and K*) and find good agreement with the data. Finally a small sample of {Lambda} was isolated form the 18.5 GeV sample and was found to have A = 0.03 {plus minus} 0.1, consistent with the model's prediction of zero.

  17. A TCT and annealing study on Magnetic Czochralski silicon detectors irradiated with neutrons and 24 GeV/ c protons

    NASA Astrophysics Data System (ADS)

    Pacifico, Nicola; Creanza, Donato; de Palma, Mauro; Manna, Norman; Kramberger, Gregor; Moll, Michael

    2010-01-01

    Silicon diodes (pad detectors) were irradiated with 24 GeV/ c protons at the CERN PS IRRAD1 facility and with neutrons at the TRIGA reactor in Ljubljana (Slovenia). The diodes were realized on Magnetic Czochralski (MCz) grown silicon, of both n- and p-type. After irradiation, an annealing study with CV measurements was performed on 24 GeV/ c proton irradiated detectors, looking for hints of type inversion after irradiation and during annealing. Other pad detectors were studied using the TCT (transient current technique), to gather information about the field profile in the detector bulk and thus about the effective space charge distribution within it.

  18. Dynamic aperture calculation for 100 GeV Au-Au and 250 GeV pp lattices with near third order resonance working point

    SciTech Connect

    Gu, X.; Luo, Y.; Fischer, W.

    2010-08-01

    In the preparation for the 2011 RHIC 250 GeV polarized proton (pp) run, both experiment and simulation were carried out to investigate the possibility to accelerate the proton beam with a vertical tune near 2/3. It had been found experimentally in Run-9 that accelerating the proton beam with a vertical tune close to 2/3 will greatly benefit the transmission of the proton polarization. In this note, we report the calculated dynamic apertures with the 100 GeV Au run and 250 GeV proton run lattices with vertical tunes close to the third order resonance. We will compare the third order resonance band width between the beam experiment and the simulation with the 100 GeV Au lattices. And we also will compare the calculated resonance band width between the 100 GeV Au and 250 GeV proton run lattices.

  19. Simulations of proton beam characteristics for ELIMED Beamline

    NASA Astrophysics Data System (ADS)

    Psikal, Jan; Limpouch, Jiri; Klimo, Ondrej; Vyskocil, Jiri; Margarone, Daniele; Korn, Georg

    2016-03-01

    ELIMED Beamline should demonstrate the capability of laser-based particle accelerators for medical applications, mainly for proton radiotherapy of tumours which requires a sufficient number of accelerated protons with energy about 60 MeV at least. In this contribution, we study the acceleration of protons by laser pulse with parameters accessible for ELIMED Beamline (intensity ∼ 1022 W/cm2, pulse length ∼ 30 fs). In our two-dimensional particle-incell simulations, we observed higher energies of protons for linear than for circular polarization. Oblique incidence of the laser pulse on target does not seem to be favourable for proton acceleration at such high intensities as the accelerated protons are deflected from target normal axis and their energy and numbers are slightly decreased. The expected numbers of accelerated protons in the energy interval 60 MeV ± 5% are calculated between 109 and 1010 per laser shot with estimated proton beam divergence about 20° (FWHM).

  20. Beam Physics for the 12 GeV CEBAF Upgrade Project

    SciTech Connect

    L. Merminga; J. F. Benesch; S.A. Bogacz; Y.-C. Chao; A. Freyberger; J.M. Grames; L. Harwood; R. Kazimi; G.A. Krafft; M. Spata; M. Tiefenback; M. Wiseman; B.C. Yunn; Y. Zhang

    2005-05-16

    Beam physics aspects of the 12 GeV Upgrade of CEBAF are presented. The CEBAF Upgrade to 12 GeV is achieved via 5.5 recirculations through the linacs, and the installation of 10 new high-gradient cryomodules. A new experimental hall, Hall D, is envisioned at the end of North Linac. Simulation results for straight-through and recirculated injectors are summarized and compared. Beam transport designs are discussed and evaluated with respect to matching and beam breakup (BBU) optimization. Effects of synchrotron radiation excitation on the beam properties are calculated. BBU simulations and derived specifications for the damping of higher order modes of the new 7-cell cavities are presented. The energies that provide longitudinal polarization in multiple experimental halls simultaneously are calculated. Finally, a detailed optics design for the Hall D transport line has been obtained.

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

    PubMed

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

    2016-08-01

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

  2. H- AND PROTON BEAM LOSS COMPARISON AT SNS SUPERCONDUCTING LINAC

    SciTech Connect

    Aleksandrov, Alexander V; Galambos, John D; Plum, Michael A; Shishlo, Andrei P

    2012-01-01

    A comparison of beam loss in the superconducting part (SCL) of the Spallation Neutron Source (SNS) linac for H- and protons is presented. During the experiment the nominal beam of negative hydrogen ions in the SCL was replaced by a proton beam created by insertion of a thin stripping carbon foil placed in the low energy section of the linac. The observed significant reduction in the beam loss for protons is explained by a domination of the intra beam stripping mechanism of the beam loss for H-. The details of the experiment are discussed, and a preliminary estimation of the cross section of the reaction H- + H- -> H- + H0 + e is presented. Earlier, a short description of these studies was presented in [1].

  3. GeV electron beams from a laser-plasma accelerator

    SciTech Connect

    Schroeder, C.B.; Toth, Cs.; Nagler, B.; Gonsalves, A.J.; Nakamura, K.; Geddes, C.G.R.; Esarey, E.; Hooker, S.M.; Leemans, W.P.

    2006-10-01

    High-quality electron beams with up to 1 GeV energy havebeen generated by a laser-driven plasma-based accelerator by guiding a 40TW peak power laser pulse in a 3.3 cm long gas-filled capillary dischargewaveguide.

  4. Nonintrusive Emittance Measurement of 1GeV H- Beam with a Laser

    SciTech Connect

    Liu, Yun; Aleksandrov, Alexander V; Long, Cary D; Menshov, Alexander A; Pogge, James R; Webster, Anthony W; Zhukov, Alexander P

    2012-01-01

    A laser wire based transverse phase space measurement system has been developed at the Spallation Neutron Source (SNS). The system allows a nonintrusive measurement of 1GeV hydrogen ion (H-) beam at the high energy beam transport (HEBT). This paper describes the design, installation, and measurement performance of the system. Major technical challenges in the implementation and commissioning of the nonintrusive phase space diagnostics at high brightness particle accelerator facilities are discussed.

  5. Test of an amorphous silicon detector in medical proton beams

    NASA Astrophysics Data System (ADS)

    Martišíková, M.; Hesse, B. M.; Nairz, O.; Jäkel, O.

    2011-05-01

    Ion beam radiation therapy for cancer treatment allows for improved dose confinement to the target in comparison with the standard radiation therapy using high energy photons. Dose delivery to the patient using focused ion beam scanning over the target volume is going to be increasingly used in the upcoming years. The high precision of the dose delivery achieved in this way has to be met by practical methods for beam monitoring with sufficient spatial resolution in two dimensions. Flat panel detectors, used for photon portal imaging at the newest medical linear accelerators, are an interesting candidate for this purpose. Initial detector tests presented here were performed using proton beams with the highest available energy. The investigations include measurements of beam profiles at different beam intensities and for different beam width, as well as the signal linearity. Radiation damage was also investigated. The obtained results show that the detector is a promising candidate to be used in the therapeutic proton beams.

  6. New Beam Loss Monitor for 12 GeV Upgrade

    SciTech Connect

    Jianxun Yan, Kelly Mahoney

    2009-10-01

    This paper describes a new VME based machine protection Beam Loss Monitor (BLM) signal processing board designed at Jefferson Lab to replace the current CAMAC based BLM board. The new eight-channel BLM signal processor has linear, logarithmic, and integrating amplifiers that simultaneously provide the optimal signal processing for each application. Amplified signals are digitized and then further processed through a Field Programmable Gate Array (FPGA). Combining both the diagnostic and machine protection functions in each channel allows the operator to tune-up and monitor beam operations while the machine protection is integrating the same signal. Other features include extensive built-in-self-test, fast shutdown interface (FSD), and 16-Mbit buffers for beam loss transient play-back. The new VME BLM board features high sensitivity, high resolution, and low cost per channel.

  7. Backward electroproduction of pi{sup 0} mesons on protons in the region of nucleon resonances at four momentum transfer squared Q2 = 1.0 GeV2

    SciTech Connect

    Laveissiere, G; Degrande, N; Jaminion, S; Jutier, C; Todor, L; Salvo, R Di; Hoorebeke, L Van

    2004-04-01

    Exclusive electroproduction of pi{sup 0} mesons on protons in the backward hemisphere has been studied at Q2 = 1.0 GeV2 by detecting protons in the forward direction in coincidence with scattered electrons from the 4 GeV electron beam in Jefferson Lab's Hall A. The data span the range of the total (gamma*p) center-of-mass energy W from the pion production threshold to W = 2.0 GeV. The differential cross sections sigma{sub T} + epsilon sigma{sub L}, sigma{sub TL}, and sigma{sub TT} were separated from the azimuthal distribution and are presented together with the MAID and SAID parameterizations.

  8. Rapidity and centrality dependence of proton and anti-proton production from 197Au+197Au collisions at {radical}(s{sub NN}) = 130 GeV

    SciTech Connect

    Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Badyal, S.K.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bhardwaj, S.; Bhaskar, P.; Bhati, A.K.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Cardenas, A.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Corral, M.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Mazumdar, M.R.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Filip, P.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Ganti, M.S.; Gutierrez, T.D.; Gagunashvili, N.; Gans, J.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grigoriev, V.; Grosnick, D.; Guedon, M.; Guertin, S.M.; Gupta, A.; Gushin, E.; Hallman, T.J.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Huang, S.L.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kaneta, M.; Kaplan, M.; Keane, D.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Konstantinov, A.S.; Kopytine, M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; et al.

    2003-06-20

    We report on the rapidity and centrality dependence of proton and anti-proton transverse mass distributions from {sup 197}Au + {sup 197}Au collisions at {radical}s{sub NN} = 130 GeV as measured by the STAR experiment at RHIC. Our results are from the rapidity and transverse momentum range of |y| < 0.5 and 0.35 < p{sub t} < 1.00 GeV/c. For both protons and anti-protons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within |y| < 0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton(anti-proton) yields and transverse mass distributions the possibility of pre-hadronic collective expansion may have to be taken into account.

  9. MEIC Proton Beam Formation with a Low Energy Linac

    SciTech Connect

    Zhang, Yuhong

    2015-09-01

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

  10. 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.

  11. Precision measurements of g1 of the proton and the deuteron with 6 GeV electrons

    SciTech Connect

    Prok, Yelena; Bosted, Peter; Kvaltine, Nicholas; Adhikari, Krishna; Adikaram-Mudiyanselage, Dasuni; Aghasyan, Mher; Amaryan, Moskov; Anderson, Mark; Anefalos Pereira, Sergio; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Biselli, Angela; Bono, Jason; Briscoe, William; Brock, Joseph; Brooks, William; Bueltmann, Stephen; Burkert, Volker; Carlin, Christopher; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Colaneri, Luca; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crabb, Donald; Crede, Volker; D'Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dupre, Raphael; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Fedotov, Gleb; Fegan, Stuart; Fersch, Robert; Fleming, Jamie; Forest, Tony; Garcon, Michel; Gevorgyan, Nerses; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Girod-Gard, Francois-Xavier; Giovanetti, Kevin; Goetz, John; Gohn, Wesley; Gothe, Ralf; Griffioen, Keith; Guegan, Baptiste; Guler, Nevzat; Hafidi, Kawtar; Hanretty, Charles; Harrison, Nathan; Hattawy, Mohammad; Hicks, Kenneth; Ho, Dao; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Jawalkar, Sucheta; Jiang, Xiaodong; Jo, Hyon-Suk; Joo, Kyungseon; Kalantarians, Narbe; Keith, Christopher; Keller, Daniel; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Koirala, Suman; Kubarovsky, Valery; Kuhn, Sebastian; Kuleshov, Sergey; Lenisa, Paolo; Livingston, Kenneth; Lu, Haiyun; MacGregor, Ian; Markov, Nikolai; Mayer, Michael; McKinnon, Bryan; Meekins, David; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; MOUTARDE, Herve; Movsisyan, Aram; Munevar Espitia, Edwin; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Paremuzyan, Rafayel; Park, K; Peng, Peng; Phillips, J J; Pierce, Joshua; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, John; Procureur, Sebastien; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Rossi, Patrizia; Roy, Priyashree; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Sharabian, Youri; Simonyan, Ani; Smith, Claude; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Stepan; Stepanyan, Samuel; Strakovski, Igor; Strauch, Steffen; Sytnik, Valeriy; Taiuti, Mauro; Tang, Wei; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vernarsky, Brian; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Weinstein, Lawrence; Zachariou, Nicholas; Zana, Lorenzo; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen; Zonta, Irene

    2014-08-01

    The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at lab angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual DIS kinematics, Q^2>1 GeV^2 and the final-state invariant mass W>2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q^2 at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative QCD, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as high-twist contributions.

  12. Design of an Aluminum Proton Beam Window for the Spallation Neutron Source

    SciTech Connect

    Janney, Jim G; McClintock, David A

    2012-01-01

    An aluminum proton beam window design is being considered at the Spallation Neutron Source primarily to increase the lifetime of the window, with secondary advantages of higher beam transport efficiency and lower activation. The window separates the core vessel, the location of the mercury target, from the vacuum of the accelerator, while withstanding the pass through of a proton beam of up to 2 MW with 1.0 GeV proton energy. The current aluminum alloy being investigated for the window material is 6061-T651 due to its combination of high strength, high thermal conductivity, and good resistance to aqueous corrosion, as well as demonstrated dependability in previous high-radiation environments. The window design will feature a thin plate with closely spaced cross drilled cooling holes. An analytical approach was used to optimize the dimensions of the window before finite element analysis was used to simulate temperature profiles and stress fields resulting from thermal and static pressure loading. The resulting maximum temperature of 60 C and Von Mises stress of 71 MPa are very low compared to allowables for Al 6061-T651. A significant challenge in designing an aluminum proton beam window for SNS is integrating the window with the current 316L SS shield blocks. Explosion bonding was chosen as a joining technique because of the large bonding area required. A test program has commenced to prove explosion bonding can produce a robust vacuum joint. Pending successful explosion bond testing, the aluminum proton beam window design will be proven acceptable for service in the Spallation Neutron Source.

  13. The dijet cross section measurement in proton-proton collisions at a center of mass energy of 500 GeV at STAR

    NASA Astrophysics Data System (ADS)

    Webb, Grant

    Polarized deep inelastic scattering experiments play a vital role in the exploration of the spin structure of the proton. The polarized proton-proton collider at RHIC provides direct access to the gluon spin distribution through longitudinal double spin asymmetry measurements of inclusive jets, pions, and dijets. This thesis presents the measurement of the dijet double differential cross-section in proton-proton collisions at center of mass energies of [sq rt]s = 500 GeV. The data represent an integrated luminosity of 8.7 pb--1 recorded by the STAR detector during the 2009 RHIC run. A comprehensive jet analysis was performed to determine the ideal jet algorithm and jet parameters used in [sq rt]s = 500 GeV collisions at the STAR detector. The cross-section is measured as a function of the dijet invariant mass (30 ≤ Mij ≤ 152 GeV) in the mid rapidity region with a maximum rapidity range of | ymax| ≤ 0.8. This result shows agreement with theoretical next-to-leading order pQCD calculations, motivating the use of dijet asymmetries at STAR to further constrain the shape of Deltag( x). KEYWORDS: Dijet Cross Section, Gluon Spin, STAR Detector, Jetography, Embedding.

  14. Dilepton production in proton-proton and quasifree proton-neutron reactions at 1.25 GeV

    SciTech Connect

    Shyam, R.; Mosel, U.

    2010-12-15

    We investigate the pp{yields}ppe{sup +}e{sup -} and quasifree pn{yields}pne{sup +}e{sup -} reactions within an effective Lagrangian model at a laboratory kinetic energy of 1.25 GeV for which experimental data have recently been reported by the HADES Collaboration. The model uses a meson-exchange approximation to describe the initial nucleon-nucleon (NN) scattering. Contributions to the reaction amplitudes are included from the NN bremsstrahlung as well as from the excitation, propagation, and radiative decay of the {Delta}(1230) isobar state. It is found that the HADES data on the e{sup +}e{sup -} invariant mass distribution in the pp{yields}ppe{sup +}e{sup -} reaction are excellently reproduced by our model where the {Delta} isobar term dominates the spectrum. In the case of the quasifree pn{yields}pne{sup +}e{sup -} reaction, a strong sensitivity to the pion electromagnetic form factor is observed which helps to bring the calculated cross sections closer to the data in the higher dilepton mass region.

  15. EXPERIMENTAL STUDY OF PROTON-BEAM HALO INDUCED BY BEAM MISMATCH IN LEDA.

    SciTech Connect

    Wangler, Thomas P.,; Allen, C. K.; Colestock, P. L. ,; Chan, K. D.; Crandall, K. R.; Garnett, R. W.; Gilpatrick, J. D.; Lysenko, W. P.; Qiang, J.; Schneider, J. D.; Sheffield, R. L.; Smith, H. V.; Schulze, M. E.

    2001-01-01

    We report measurements of transverse beam halo in mismatched proton beams in a 52-quadrupole FODO transport channel following the 6.7-MeV LEDA RFQ. Beam profiles in both transverse planes are measured using beam-profile diagnostic devices that consist of a movable carbon filament for measurement of the dense beam core, and scraper plates for measurement of the halo. The gradients of the first four quadrupoles can be independently adjusted to mismatch the RFQ output beam into the beam-transport channel. The properties of the measured mismatched beam profiles in the transport channel will be compared with predictions from multiparticle beam-dynamics simulations.

  16. Numerical studies of electron acceleration behind self-modulating proton beam in plasma with a density gradient

    NASA Astrophysics Data System (ADS)

    Petrenko, A.; Lotov, K.; Sosedkin, A.

    2016-09-01

    Presently available high-energy proton beams in circular accelerators carry enough momentum to accelerate high-intensity electron and positron beams to the TeV energy scale over several hundred meters of the plasma with a density of about 1015cm-3. However, the plasma wavelength at this density is 100-1000 times shorter than the typical longitudinal size of the high-energy proton beam. Therefore the self-modulation instability (SMI) of a long (~10 cm) proton beam in the plasma should be used to create the train of micro-bunches which would then drive the plasma wake resonantly. Changing the plasma density profile offers a simple way to control the development of the SMI and the acceleration of particles during this process. We present simulations of the possible use of a plasma density gradient as a way to control the acceleration of the electron beam during the development of the SMI of a 400 GeV proton beam in a 10 m long plasma. This work is done in the context of the AWAKE project-the proof-of-principle experiment on proton driven plasma wakefield acceleration at CERN.

  17. Feasibility of Near field ODR Imaging of Multi GeV Electron Beams at CEBAF

    SciTech Connect

    A.H. Lumpkin; P. Evtushenko; Arne P. Freyberger; C. Liu

    2007-08-01

    We have evaluated the feasibility of using the optical diffraction radiation (ODR) generated as a 1- to 6-GeV CW electron beam passes nearby the edge of a single metal conducting plane as a nonintercepting (NI) relative beam size monitor for CEBAF. Previous experiments were successfully done using near-field imaging on the lower-current, 7-GeV beam at APS, and an analytical model was developed for near-field imaging. Calculations from this model indicate sufficient beam-size sensitivity in the ODR profiles for beam sizes in the 30-50 micron regime as found in the transport lines of CEBAF before the experimental targets. With anticipated beam currents of 100 microamps, the ODR signal from the charge integrated over the video field time should be ~500 times larger than in the APS case. These signal strengths will allow a series of experiments to be done on beam energy dependencies, impact parameters, polarization effects, and wavelength effects that should further elucidate the working regime of this technique and test the model. Plans for the diagnostics station that will also provide reference optical transition radiation (OTR) images will also be described.

  18. Proton-Proton Correlation in Central Collisions of Lanthanum + Lanthanum at 1.2 Gev/a

    NASA Astrophysics Data System (ADS)

    Chang, James W.

    1992-01-01

    Central collisions between 1.2 GeV/A lanthanum projectiles and lanthanum nuclei are analysed for HBT-based proton-proton (pp) correlation. The La + La collision system is unique in that it has both the largest beam and beam + target size in any of the pp correlation analyses performed. The data is obtained from LBL's BEVALAC experiment E684HX. The time-of-flight system also with the Heavy Ion Spectrometer System (HISS) allows identification of protons at average mass resolution of 40.6 MeV (5%). The systematic background is removed from the correlation by the event-mixing method. The correlation from data is compared to the calculated correlation which uses a Gaussian source distribution and pp wavefunction resulting from Fermi statistics, S-wave Reid soft-core nuclear potential, and full Coulomb potential. The RMS radius of the La + La system is found to be 4.90 +/- 0.22 fm when systematic corrections are applied. When this radius (r_sp{RMS}{p }) is compared to the radius obtained using pion-pion correlation on the same data (r_sp {RMS}{pi} = 7.31 +/- 0.29 fm), it is found that the r _sp{RMS}{p}/r_sp{RMS }{pi} ratio is 0.67. Survey of other proton and pion correlation results from same systems reveal that r_sp{RMS} {p} < r_sp{RMS}{pi } in general, with the ratio r_sp {RMS}{p}/r_sp{RMS} {pi} decreasing with increase in colliding system size. Survey of pp correlation results from other experiments are considered to test the bore -cut and billiard-ball models. It is found that when the system is large (A_{total} > 118), the bore-cut model underestimates the size, and the billiard-ball model overestimates the size. The billiard -ball model looks attractive due to the smoothness of the transition between correct size estimation and overestimation. A conjecture is made that if this model is true, then the over-estimation of size may be a signature of nucleon density increase at large colliding systems. Compromise scenarios between the bore-cut and billiard-ball models

  19. A CW superconducting linac as the proton driver for a medium baseline neutrino beam in China

    NASA Astrophysics Data System (ADS)

    Li, Zhi-Hui; Tang, Jing-Yu

    2014-12-01

    In a long-term planning for neutrino experiments in China, a medium baseline neutrino beam is proposed which uses a continue wave (CW) superconducting linac of 15 MW in beam power as the proton driver. The linac will be based on the technologies which are under development by the China-ADS project, namely it is also composed of a 3.2 MeV normal conducting RFQ and five different types of superconducting cavities. However, the design philosophy is quite different from the China-ADS linac because of the much weaker requirement on reliability here. The nominal design energy and current are 1.5 GeV and 10 mA, respectively. The general considerations and preliminary results on the physics design will be presented here. In addition, the alternative designs such as 2.0 GeV and 2.5 GeV, which may be required by the general design, can be easily extended from the nominal one.

  20. Spill uniformity measurements for a raster scanned proton beam

    NASA Astrophysics Data System (ADS)

    Coutrakon, G.; Ghebremedhin, A.; Koss, P.; Evans, K.; Taylor, D.; Jenkins, G.

    2000-11-01

    The method of scanning a proton beam across a target region for radiation therapy requires a uniform beam intensity throughout the beam spill time. Achieving uniform intensity using feedback to an air core quadrapole in the Loma Linda synchrotron accelerator is described in this paper. Frequency domain transfer functions and time domain intensity ripple measurements are presented followed with results and discussion of issues requiring additional work.

  1. Spill uniformity measurements for a raster scanned proton beam

    NASA Astrophysics Data System (ADS)

    Coutrakon, G.; Ghebremedhin, A.; Johanning, J.; Koss, P.

    1997-02-01

    The method of scanning a proton beam across a target region for radiation therapy requires a uniform beam intensity throughout the beam spill time. Achieving uniform intensity using feedback to an air core quadrupole in the Loma Linda synchrotron accelerator is described in this paper. Frequency domain transfer functions and time domain intensity ripple measurements are presented followed with results and discussion of issues requiring additional work.

  2. A new luminescence beam profile monitor for intense proton and heavy ion beams

    SciTech Connect

    Tsang,T.; Bellavia, S.; Connolly, R.; Gassner, D.; Makdisi, Y.; Russo, T.; Thieberger, P.; Trbojevic, D.; Zelenski, A.

    2008-10-01

    A new luminescence beam profile monitor is realized in the polarized hydrogen gas jet target at the Relativistic Heavy Ion Collider (RHIC) facility. In addition to the spin polarization of the proton beam being routinely measured by the hydrogen gas jet, the luminescence produced by beam-hydrogen excitation leads to a strong Balmer series lines emission. A selected hydrogen Balmer line is spectrally filtered and imaged to produce the transverse RHIC proton beam shape with unprecedented details on the RHIC beam profile. Alternatively, when the passage of the high energy RHIC gold ion beam excited only the residual gas molecules in the beam path, sufficient ion beam induced luminescence is produced and the transverse gold ion beam profile is obtained. The measured transverse beam sizes and the calculated emittances provide an independent confirmation of the RHIC beam characteristics and to verify the emittance conservation along the RHIC accelerator. This optical beam diagnostic technique by making use of the beam induced fluorescence from injected or residual gas offers a truly noninvasive particle beam characterization, and provides a visual observation of proton and heavy ion beams. Combined with a longitudinal bunch measurement system, a 3-dimensional spatial particle beam profile can be reconstructed tomographically.

  3. Beam Optics for a Scanned Proton Beam at Loma Linda University Medical Center

    SciTech Connect

    Coutrakon, George; Hubbard, Jeff; Koss, Peter; Sanders, Ed; Panchal, Mona

    2003-08-26

    Beam scanning in proton therapy is a medical technique to lower the dose to healthy tissue while irradiating a tumor volume. Scanned proton beams for proton radiation therapy require small beam sizes at the tumor location. In beam scanning, a small beam usually less than 1 cm diameter is swept across the tumor volume with two magnets located several meters upstream of the patient. In general, all proton beams in a therapy facility must be transported from the accelerator to the treatment rooms where the scanning systems are located. This paper addresses the problem of transporting the beam without losses to the patient and achieving a small beam at the tumor location in the patient. The strengths of the beam line quadrupoles were allowed to vary to produce the desired beam sizes along the beam lines. Quadrupole strengths were obtained using the beam simulation program TRANSPORT originally from Stanford Linear Accelerator Center in Palo Alto, CA. An enhanced version of the original program by Accel Soft Inc. in San Diego, CA has been used for these studies. Beam size measurements were used for comparison with TRANSPORT to verify the predictions of TRANSPORT calculations.

  4. Beam Optics for a Scanned Proton Beam at Loma Linda University Medical Center

    NASA Astrophysics Data System (ADS)

    Coutrakon, George; Hubbard, Jeff; Koss, Peter; Sanders, Ed; Panchal, Mona

    2003-08-01

    Beam scanning in proton therapy is a medical technique to lower the dose to healthy tissue while irradiating a tumor volume. Scanned proton beams for proton radiation therapy require small beam sizes at the tumor location. In beam scanning, a small beam usually less than 1 cm diameter is swept across the tumor volume with two magnets located several meters upstream of the patient. In general, all proton beams in a therapy facility must be transported from the accelerator to the treatment rooms where the scanning systems are located. This paper addresses the problem of transporting the beam without losses to the patient and achieving a small beam at the tumor location in the patient. The strengths of the beam line quadrupoles were allowed to vary to produce the desired beam sizes along the beam lines. Quadrupole strengths were obtained using the beam simulation program TRANSPORT originally from Stanford Linear Accelerator Center in Palo Alto, CA. An enhanced version of the original program by Accel Soft Inc. in San Diego, CA has been used for these studies. Beam size measurements were used for comparison with TRANSPORT to verify the predictions of TRANSPORT calculations.

  5. GeV Electron Beams from a Capillary Discharge Guided Laser Plasma Accelerator

    SciTech Connect

    Nakamura, Kei; Gonsalves, Anthony; Panasenko, Dmitriy; Lin, Chen; Toth, Csaba; Geddes, Cameron; Schroeder, Carl; Esarey, Eric; Leemans, Wim

    2010-07-08

    Laser plasma acceleration (LPA) up to 1 GeV has been realized at Lawrence Berkeley National Laboratory by using a capillary discharge waveguide. In this paper, the capillary discharge guided LPA system including a broadband single-shot electron spectrometer is described. The spectrometer was designed specifically for LPA experiments and has amomentumacceptance of 0.01 - 1.1 GeV/c with a percent level resolution. Experiments using a 33 mm long, 300 mu m diameter capillary demonstrated the generation of high energy electron beams up to 1 GeV. By de-tuning discharge delay from optimum guiding performance, selftrapping and acceleration were found to be stabilized producing 460 MeV electron beams.

  6. Measurements of neutron dose equivalent for a proton therapy center using uniform scanning proton beams

    SciTech Connect

    Zheng Yuanshui; Liu Yaxi; Zeidan, Omar; Schreuder, Andries Niek; Keole, Sameer

    2012-06-15

    Purpose: Neutron exposure is of concern in proton therapy, and varies with beam delivery technique, nozzle design, and treatment conditions. Uniform scanning is an emerging treatment technique in proton therapy, but neutron exposure for this technique has not been fully studied. The purpose of this study is to investigate the neutron dose equivalent per therapeutic dose, H/D, under various treatment conditions for uniform scanning beams employed at our proton therapy center. Methods: Using a wide energy neutron dose equivalent detector (SWENDI-II, ThermoScientific, MA), the authors measured H/D at 50 cm lateral to the isocenter as a function of proton range, modulation width, beam scanning area, collimated field size, and snout position. They also studied the influence of other factors on neutron dose equivalent, such as aperture material, the presence of a compensator, and measurement locations. They measured H/D for various treatment sites using patient-specific treatment parameters. Finally, they compared H/D values for various beam delivery techniques at various facilities under similar conditions. Results: H/D increased rapidly with proton range and modulation width, varying from about 0.2 mSv/Gy for a 5 cm range and 2 cm modulation width beam to 2.7 mSv/Gy for a 30 cm range and 30 cm modulation width beam when 18 Multiplication-Sign 18 cm{sup 2} uniform scanning beams were used. H/D increased linearly with the beam scanning area, and decreased slowly with aperture size and snout retraction. The presence of a compensator reduced the H/D slightly compared with that without a compensator present. Aperture material and compensator material also have an influence on neutron dose equivalent, but the influence is relatively small. H/D varied from about 0.5 mSv/Gy for a brain tumor treatment to about 3.5 mSv/Gy for a pelvic case. Conclusions: This study presents H/D as a function of various treatment parameters for uniform scanning proton beams. For similar treatment

  7. Characteristics of proton beams and secondary neutrons arising from two different beam nozzles

    NASA Astrophysics Data System (ADS)

    Choi, Yeon-Gyeong; Kim, Yu-Seok

    2015-10-01

    A tandem or a Van de Graaff accelerator with an energy of 3 MeV is typically used for Proton Induced X-ray Emission (PIXE) analysis. In this study, the beam line design used in the PIXE analysis, instead of the typical low-energy accelerator, was used to increase the production of isotopes from a 13-MeV cyclotron. For the PIXE analysis, the proton beam should be focused at the target through a nozzle after degrading the proton beams energy from 13 MeV to 3 MeV by using an energy degrader. Previous studies have been conducted to determine the most appropriate material for and the thickness of the energy degrader. From the energy distribution of the degraded proton beam and the neutron occurrence rate at the degrader, an aluminum nozzle of X thickness was determined to be the most appropriate nozzle construction. Neutrons are created by the collision of 3-MeV protons in the nozzle after passage through the energy degrader. In addition, a proton beam of sufficient intensity is required for a non-destructive PIXE analysis. Therefore, if nozzle design is to be optimized, the number of neutrons that arise from the collision of protons inside the nozzle, as well as the track direction of the generated secondary neutrons, must be considered, with the primary aim of ensuring that a sufficient number of protons pass through the nozzle as a direct beam. A number of laboratories are currently conducting research related to the design of nozzles used in accelerator fields, mostly medical fields. This paper presents a comparative analysis of two typical nozzle shapes in order to minimize the loss of protons and the generation of secondary neutrons. The neutron occurrence rate and the number of protons that pass through the nozzle were analyzed by using a Particle and Heavy Ion Transport code System (PHITS) program in order to identify the nozzle that generated the strongest proton beam.

  8. Single-Plane Magnetically Focused Elongated Small Field Proton Beams.

    PubMed

    McAuley, Grant A; Slater, James M; Wroe, Andrew J

    2015-08-01

    We previously performed Monte Carlo simulations of magnetically focused proton beams shaped by a single quadrapole magnet and thereby created narrow elongated beams with superior dose delivery characteristics (compared to collimated beams) suitable for targets of similar geometry. The present study seeks to experimentally validate these simulations using a focusing magnet consisting of 24 segments of samarium cobalt permanent magnetic material adhered into a hollow cylinder. Proton beams with properties relevant to clinical radiosurgery applications were delivered through the magnet to a water tank containing a diode detector or radiochromic film. Dose profiles were analyzed and compared with analogous Monte Carlo simulations. The focused beams produced elongated beam spots with high elliptical symmetry, indicative of magnet quality. Experimental data showed good agreement with simulations, affirming the utility of Monte Carlo simulations as a tool to model the inherent complexity of a magnetic focusing system. Compared to target-matched unfocused simulations, focused beams showed larger peak to entrance ratios (26% to 38%) and focused simulations showed a two-fold increase in beam delivery efficiency. These advantages can be attributed to the magnetic acceleration of protons in the transverse plane that tends to counteract the particle outscatter that leads to degradation of peak to entrance performance in small field proton beams. Our results have important clinical implications and suggest rare earth focusing magnet assemblies are feasible and could reduce skin dose and beam number while delivering enhanced dose to narrow elongated targets (eg, in and around the spinal cord) in less time compared to collimated beams. PMID:25414143

  9. Effect of Scanning Beam for Superficial Dose in Proton Therapy.

    PubMed

    Moskvin, Vadim P; Estabrook, Neil C; Cheng, Chee-Wai; Das, Indra J; Johnstone, Peter A S

    2015-10-01

    Proton beam delivery technology is under development to minimize the scanning spot size for uniform dose to target, but it is also known that the superficial dose could be as high as the dose at Bragg peak for narrow and small proton beams. The objective of this study is to explore the characteristics of dose distribution at shallow depths using Monte Carlo simulation with the FLUKA code for uniform scanning (US) and discrete spot scanning (DSS) proton beams. The results show that the superficial dose for DSS is relatively high compared to US. Additionally, DSS delivers a highly heterogeneous dose to the irradiated surface for comparable doses at Bragg peak. Our simulation shows that the superficial dose can become as high as the Bragg peak when the diameter of the proton beam is reduced. This may compromise the advantage of proton beam therapy for sparing normal tissue, making skin dose a limiting factor for the clinical use of DSS. Finally, the clinical advantage of DSS may not be essential for treating uniform dose across a large target, as in craniospinal irradiation (CSI). PMID:24945369

  10. Transverse beam coupling impedance of the CERN Proton Synchrotron

    NASA Astrophysics Data System (ADS)

    Persichelli, S.; Migliorati, M.; Biancacci, N.; Gilardoni, S.; Metral, E.; Salvant, B.

    2016-04-01

    Beam coupling impedance is a fundamental parameter to characterize the electromagnetic interaction of a particle beam with the surrounding environment. Synchrotron machine performances are critically affected by instabilities and collective effects triggered by beam coupling impedance. In particular, transverse beam coupling impedance is expected to impact beam dynamics of the CERN Proton Synchrotron (PS), since a significant increase in beam intensity is foreseen within the framework of the LHC Injectors Upgrade (LIU) project. In this paper we describe the study of the transverse beam coupling impedance of the PS, taking into account the main sources of geometrical impedance and the contribution of indirect space charge at different energies. The total machine impedance budget, determined from beam-based dedicated machine measurement sessions, is also discussed and compared with the theoretical model.

  11. Lattice for a 1. 1-GeV 500. mu. A fast-cycling proton synchrotron

    SciTech Connect

    Cho, Y.

    1983-01-01

    A very-high-intensity proton synchrotron lattice has been designed for a spallation neutron-source system. The synchrotron is to accelerate a beam of 6.25 x 10/sup 13/ protons from 200 MeV to 1100 MeV in 15 msec. One of the important concerns for high-intensity, high-rep-rate (50 pulses/sec) machines is stability of the beam. Considerations of the transverse space-charge limits and the transverse-stability criterion favor a high-tune machine over a low-tune machine of the same circumference. For these reasons, we made the tune as high as possible by making the cell length as short as possible. The lattice proposed here consists of four sectors, and each sector is made up by three FODO normal cells, four dispersion suppressor cells, and four matching and straight section cells. Then the total of 44 cells with approximately 90/sup 0//cell phase advance would make the natural tune of the machine to be near 11.

  12. Study of open charm production in proton+proton collisions at center of mass energies = 200 GeV

    NASA Astrophysics Data System (ADS)

    Butsyk, Sergey

    2005-11-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) with its unique electron identification system enables us to perform high precision measurements of electron yields. By measuring electron production at high transverse momentum, we can disentangle the contribution of electrons originating from semi-leptonic decays of heavy quarks (charm or bottom) from the less interesting "photonic" decay modes of light mesons. D/B mesons carry single heavy valence quarks and are usually referred to as "Open Charm" and "Open Bottom" particles, differentiating them from Closed Flavor particles such as J/psi, and Y mesons. Due to the large mass of the heavy quarks, their production mechanisms can be adequately explained by perturbative QCD (pQCD) theory. This dissertation presents the measurement of electrons from heavy flavor decays in proton + proton collisions at RHIC at collision energy s = 200 GeV over a wide range of transverse moment (0.4 < pT < 5 GeV/c). Two independent analysis techniques of signal extraction were performed. The "Cocktail" subtraction is based on the calculation and subtraction of the expected "photon-related" electron background based upon measured yields of light mesons. The "Converter" subtraction is based upon a direct measurement of photon yields achieved introducing additional material in the PHENIX acceptance and deducing the photon abundance by measuring the increase in electron yield. This is the first measurement of the Open Charm crossection at this collision energy and it is an important baseline measurement for comparison with nucleus + nucleus collisions. The modification of Open Charm production in heavy ion collisions compared to the presented p + p result can be used to study the final state interaction of the heavy quarks with hot dense matter inside the collisions. The results of the Open Charm measurements are compared to current pQCD predictions both in Leading Order (LO) O a2s and Next-to-Leading Order (NLO) O a3s

  13. Characterizing a proton beam with two different methods in beam halo experiments

    NASA Astrophysics Data System (ADS)

    Jiang, Hong-Ping; Fu, Shi-Nian; Peng, Jun; Cheng, Peng; Huang, Tao; Li, Peng; Li, Fang; Li, Jian; Liu, Hua-Chang; Liu, Mei-Fei; Meng, Ming; Meng, Cai; Mu, Zhen-Cheng; Rong, Lin-Yan; Ouyang, Hua-Fu; Sun, Biao; Wang, Bo; Tian, Jian-Min; Wang, Biao; Wang, Sheng-Chang; Yao, Yuan; Xu, Tao-Guang; Xu, Xin-An; Xin, Wen-Qu; Zhao, Fu-Xiang; Zeng, Lei; Zhou, Wen-Zhong

    2014-08-01

    In beam halo experiments, it is very important to correctly characterize the RFQ output proton beam. In order to simulate the beam dynamics properly, we must first know the correct initial beam parameters. We have used two different methods, quadrupole scans and multi-wire scanners to determine the transverse phase-space properties of the proton beam. The experimental data were analyzed by fitting to the 3-D nonlinear simulation code IMPACT. For the quadrupole scan method, we found that the RMS beam radius and the measured beam-core profiles agreed very well with the simulations. For the multi-wire scanner method, we choose the case of a matched beam. By fitting the IMPACT simulation results to the measured data, we obtained the Courant-Snyder parameters and the emittance of the beam. The difference between the two methods is about eight percent, which is acceptable in our experiments.

  14. Angular distributions of 1 GeV protons channeled in bent short single-wall carbon nanotubes

    NASA Astrophysics Data System (ADS)

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

    2005-04-01

    This study is devoted to the angular distribution of protons of the energy of 1 GeV channeled in a bent short rope of (10, 10) single-wall carbon nanotubes as a function of the bending angle. The rope length was chosen to be 7 μm, corresponding to the reduced rope length associated with the transverse proton motion inside a nanotube equal to 0.103. The bending angle was varied between 0 and 1.5 mrad. The angular distributions of channeled protons and the corresponding rainbow patterns were generated using the theory of crystal rainbows, with the Molière's expression for the continuum potential of the rope. The results obtained show that the total yield of protons channeled in the rope as a function of the bending angle has the inflection point at 0.45 mrad, and that it falls below 10% of the yield for the straight rope at 1.25 mrad.

  15. Application of Monte Carlo to Proton Beam Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Siebers, J. V.

    As with photon and electron radiotherapy, the future of dose calculation for hadron beams will be based upon Monte Carlo algorithms. Benchmark calculations of the LAHET Monte Carlo code with respect to measured in-phantom dose distributions show that the proton physics modules in LAHET accurately reproduce measured results. Since MCNP-X incorporates the proton and high energy neutron physics modules from LAHET, similar agreement with MCNP-X is expected. In addition to beam-line simulations, MCNP-X has the ability to input the lattice geometry required for simulating patient treatments based on CT data sets. The ability of MCNP-X to perform patient dose calculation simulations for proton radiotherapy was demonstrated by simulating a two-beam prostate treatment plan. While MCNP-X is fully capable to perform patient-planning calculations, currently, it is too time consuming to be used for routine patient planning.

  16. External-Beam Accelerated Partial Breast Irradiation Using Multiple Proton Beam Configurations

    SciTech Connect

    Wang Xiaochun; Amos, Richard A.; Zhang Xiaodong; Taddei, Phillip J.; Woodward, Wendy A.; Hoffman, Karen E.; Yu, Tse Kuan; Tereffe, Welela; Oh, Julia; Perkins, George H.; Salehpour, Mohammad; Zhang, Sean X.; Sun, Tzou Liang; Gillin, Michael; Buchholz, Thomas A.; Strom, Eric A.

    2011-08-01

    Purpose: To explore multiple proton beam configurations for optimizing dosimetry and minimizing uncertainties for accelerated partial breast irradiation (APBI) and to compare the dosimetry of proton with that of photon radiotherapy for treatment of the same clinical volumes. Methods and Materials: Proton treatment plans were created for 11 sequential patients treated with three-dimensional radiotherapy (3DCRT) photon APBI using passive scattering proton beams (PSPB) and were compared with clinically treated 3DCRT photon plans. Monte Carlo calculations were used to verify the accuracy of the proton dose calculation from the treatment planning system. The impact of range, motion, and setup uncertainty was evaluated with tangential vs. en face beams. Results: Compared with 3DCRT photons, the absolute reduction of the mean of V100 (the volume receiving 100% of prescription dose), V90, V75, V50, and V20 for normal breast using protons are 3.4%, 8.6%, 11.8%, 17.9%, and 23.6%, respectively. For breast skin, with the similar V90 as 3DCRT photons, the proton plan significantly reduced V75, V50, V30, and V10. The proton plan also significantly reduced the dose to the lung and heart. Dose distributions from Monte Carlo simulations demonstrated minimal deviation from the treatment planning system. The tangential beam configuration showed significantly less dose fluctuation in the chest wall region but was more vulnerable to respiratory motion than that for the en face beams. Worst-case analysis demonstrated the robustness of designed proton beams with range and patient setup uncertainties. Conclusions: APBI using multiple proton beams spares significantly more normal tissue, including nontarget breast and breast skin, than 3DCRT using photons. It is robust, considering the range and patient setup uncertainties.

  17. Study of Polarized Sea Quark Distributions in Polarized Proton-Proton Collisions at sq root(s) = 500 GeV with PHENIX

    SciTech Connect

    Mibe, Tsutomu

    2009-08-04

    The PHENIX spin program studies the flavor structure of the polarized sea quark distributions in polarized proton-proton collisions. Starting from 2009 run, the quark and antiquark polarization, sorted by flavor, will be investigated with the parity-violating single-spin asymmetry of W-boson production at the collision energy of sq root(s) = 500 GeV. High momentum muons from W-boson decay are detected in the PHENIX muon arms. The muon trigger is being upgraded to allow one to select high momentum muons.

  18. Atomic Number Dependence of Hadron Production at Large Transverse Momentum in 300 GeV Proton--Nucleus Collisions

    DOE R&D Accomplishments Database

    Cronin, J. W.; Frisch, H. J.; Shochet, M. J.; Boymond, J. P.; Mermod, R.; Piroue, P. A.; Sumner, R. L.

    1974-07-15

    In an experiment at the Fermi National Accelerator Laboratory we have compared the production of large transverse momentum hadrons from targets of W, Ti, and Be bombarded by 300 GeV protons. The hadron yields were measured at 90 degrees in the proton-nucleon c.m. system with a magnetic spectrometer equipped with 2 Cerenkov counters and a hadron calorimeter. The production cross-sections have a dependence on the atomic number A that grows with P{sub 1}, eventually leveling off proportional to A{sup 1.1}.

  19. Strange magnetic form factor of the proton at $Q^2 = 0.23$ GeV$^2$

    SciTech Connect

    Wang, Ping; Leinweber, Derek; Thomas, Anthony; Young, Ross

    2009-06-01

    We determine the $u$ and $d$ quark contributions to the proton magnetic form factor at finite momentum transfer by applying chiral corrections to quenched lattice data. Heavy baryon chiral perturbation theory is applied at next to leading order in the quenched, and full QCD cases for the valence sector using finite range regularization. Under the assumption of charge symmetry these values can be combined with the experimental values of the proton and neutron magnetic form factors to deduce a relatively accurate value for the strange magnetic form factor at $Q^2=0.23$ GeV$^2$, namely $G_M^s=-0.034 \\pm 0.021$ $\\mu_N$.

  20. Inclusive production of the Δ(1232) resonance in muon-proton scattering at 280 GEV/c

    NASA Astrophysics Data System (ADS)

    Arneodo, M.; Arvidson, A.; Aubert, J. J.; Badelek, B.; Beaufays, J.; Bee, C. P.; Benchouk, C.; Berghoff, G.; Bird, I.; Blum, D.; Böhm, E.; De Bouard, X.; Brasse, F. W.; Braun, H.; Broll, C.; Brown, S.; Brück, H.; Calen, H.; Chima, J. S.; Ciborowski, J.; Clifft, R.; Coignet, G.; Combley, F.; Coughlan, J.; D'Agostini, G.; Dahlgren, S.; Dengler, F.; Derado, I.; Dreyer, T.; Drees, J.; Düren, M.; Eckardt, V.; Edwards, A.; Ernst, T.; Eszes, G.; Favier, J.; Ferrero, M. I.; Figiel, J.; Flauger, W.; Foster, J.; Gabathuler, E.; Gajewski, J.; Gamet, R.; Gayler, J.; Geddes, N.; Giubellino, P.; Graftström, P.; Grard, F.; Haas, J.; Hagberg, E.; Hasert, F. J.; Hayman, P.; Heusse, P.; Hoppe, C.; Jaffré, M.; Jacholkowska, A.; Janata, F.; Jancso, G.; Johnson, A. S.; Kabuss, E. M.; Kellner, G.; Korbel, V.; Krüger, J.; Kullander, S.; Landgraf, U.; Lanske, D.; Loken, J.; Long, K.; Maire, M.; Malecki, P.; Manz, A.; Maselli, S.; Mohr, W.; Montanet, F.; Montgomery, H. E.; Nagy, E.; Nassalski, J.; Norton, P. R.; Oakham, F. G.; Osborne, A. M.; Pascaud, C.; Pawlik, B.; Payre, P.; Peroni, C.; Pessard, H.; Pettingale, J.; Pietrzyk, B.; Pönsgen, B.; Pötsch, M.; Renton, P.; Ribarics, P.; Rith, K.; Rondio, E.; Scheer, M.; Schlagböhmer, A.; Schiemann, H.; Schmitz, N.; Schneegans, M.; Scholz, M.; Schröder, T.; Schouten, M.; Schultze, K.; Sloan, T.; Stier, H. E.; Studt, M.; Taylor, G. N.; Thénard, J. M.; Thompson, J. C.; De La Torre, A.; Toth, J.; Urban, L.; Urban, L.; Wallucks, W.; Whalley, M.; Wheeler, S.; Williams, W. S. C.; Wimpenny, S. J.; Windmolders, R.; Wolf, G.; European Muon Collaboration

    1986-01-01

    Inclusive production of the Δ (1232) resonance has been measured in 280 GeV/ c muon-proton interactions. The production of the Δ++ as a function of the variables χBJ, W, Q2, χF and pT2 is investigated. The average Δ++ multiplicity is found to be smaller, by a factor of 6.2 ± 1.2, than the average multiplicity of protons. An upper limit for Δ0 production is obtained. The net hadronic charge distribution for events with a Δ++ is presented. The results are compared to the predictions of the Lund and Fire string models.

  1. Dynamics of RF captured cooled proton beams

    SciTech Connect

    Kells, W.; Mills, F.

    1983-01-01

    In the course of electron cooling experiments at the Electron Cooling Ring (ECR) at Fermilab, several peculiar features of the longitudinal phase space of cold protons (200 MeV) captured in RF buckets were observed. Here we present the experimental facts, present a simple theory, and summarize computer simulation results which support the theory and facts.

  2. Beam acceleration through proton radio frequency quadrupole accelerator in BARC

    NASA Astrophysics Data System (ADS)

    Bhagwat, P. V.; Krishnagopal, S.; Mathew, J. V.; Singh, S. K.; Jain, P.; Rao, S. V. L. S.; Pande, M.; Kumar, R.; Roychowdhury, P.; Kelwani, H.; Rama Rao, B. V.; Gupta, S. K.; Agarwal, A.; Kukreti, B. M.; Singh, P.

    2016-05-01

    A 3 MeV proton Radio Frequency Quadrupole (RFQ) accelerator has been designed at the Bhabha Atomic Research Centre, Mumbai, India, for the Low Energy High Intensity Proton Accelerator (LEHIPA) programme. The 352 MHz RFQ is built in 4 segments and in the first phase two segments of the LEHIPA RFQ were commissioned, accelerating a 50 keV, 1 mA pulsed proton beam from the ion source, to an energy of 1.24 MeV. The successful operation of the RFQ gave confidence in the physics understanding and technology development that have been achieved, and indicate that the road forward can now be traversed rather more quickly.

  3. Dense Monoenergetic Proton Beams from Chirped Laser-Plasma Interaction

    NASA Astrophysics Data System (ADS)

    Galow, Benjamin J.; Salamin, Yousef I.; Liseykina, Tatyana V.; Harman, Zoltán; Keitel, Christoph H.

    2011-10-01

    Interaction of a frequency-chirped laser pulse with single protons and a hydrogen gas target is studied analytically and by means of particle-in-cell simulations, respectively. The feasibility of generating ultraintense (107 particles per bunch) and phase-space collimated beams of protons (energy spread of about 1%) is demonstrated. Phase synchronization of the protons and the laser field, guaranteed by the appropriate chirping of the laser pulse, allows the particles to gain sufficient kinetic energy (around 250 MeV) required for such applications as hadron cancer therapy, from state-of-the-art laser systems of intensities of the order of 1021W/cm2.

  4. Velocity Distributions and Proton Beam Production in the Solar Wind

    SciTech Connect

    Pierrard, Viviane; Voitenko, Yuriy

    2010-03-25

    Helios, Ulysses, and Wind spacecraft have observed the velocity distribution functions (VDFs) of solar wind particles deviating significantly from Maxwellians. We review recent models using different approximations and mechanisms that determine various observed characteristics of the VDFs for the electrons, protons and minor ions. A new generation mechanism is proposed for super-Alfvenic proton beams and tails that are often observed in the fast solar wind. The mechanism is based on the proton trapping and acceleration by kinetic Alfven waves (KAWs), which carry a field-aligned potential well propagating with super-Alfven velocities.

  5. How proton pulse characteristics influence protoacoustic determination of proton-beam range: simulation studies.

    PubMed

    Jones, Kevin C; Seghal, Chandra M; Avery, Stephen

    2016-03-21

    The unique dose deposition of proton beams generates a distinctive thermoacoustic (protoacoustic) signal, which can be used to calculate the proton range. To identify the expected protoacoustic amplitude, frequency, and arrival time for different proton pulse characteristics encountered at hospital-based proton sources, the protoacoustic pressure emissions generated by 150 MeV, pencil-beam proton pulses were simulated in a homogeneous water medium. Proton pulses with Gaussian widths ranging up to 200 μs were considered. The protoacoustic amplitude, frequency, and time-of-flight (TOF) range accuracy were assessed. For TOF calculations, the acoustic pulse arrival time was determined based on multiple features of the wave. Based on the simulations, Gaussian proton pulses can be categorized as Dirac-delta-function-like (FWHM < 4 μs) and longer. For the δ-function-like irradiation, the protoacoustic spectrum peaks at 44.5 kHz and the systematic error in determining the Bragg peak range is <2.6 mm. For longer proton pulses, the spectrum shifts to lower frequencies, and the range calculation systematic error increases (⩽ 23 mm for FWHM of 56 μs). By mapping the protoacoustic peak arrival time to range with simulations, the residual error can be reduced. Using a proton pulse with FWHM = 2 μs results in a maximum signal-to-noise ratio per total dose. Simulations predict that a 300 nA, 150 MeV, FWHM = 4 μs Gaussian proton pulse (8.0 × 10(6) protons, 3.1 cGy dose at the Bragg peak) will generate a 146 mPa pressure wave at 5 cm beyond the Bragg peak. There is an angle dependent systematic error in the protoacoustic TOF range calculations. Placing detectors along the proton beam axis and beyond the Bragg peak minimizes this error. For clinical proton beams, protoacoustic detectors should be sensitive to <400 kHz (for -20 dB). Hospital-based synchrocyclotrons and cyclotrons are promising sources of proton pulses for generating clinically measurable protoacoustic

  6. Commissioning of polarized-proton and antiproton beams at Fermilab

    SciTech Connect

    Yokosawa, A.

    1988-05-04

    The author described the polarized-proton and polarized-antiproton beams up to 200 GeV/c at Fermilab. The beam line, called MP, consists of the 400-m long primary and 350-m long secondary beam line followed by 60-m long experimental hall. We discuss the characteristics of the polarized beams. The Fermilab polarization projects are designated at E-581/704 initiated and carried out by an international collaboration, Argonne (US), Fermilab (US), Kyoto-Kyushu-Hiroshima-KEK (Japan), LAPP (France), Northwestern University (US), Los Alamos Laboratory (US), Rice (US), Saclay (France), Serpukhov (USSR), INFN Trieste (Italy), and University of Texas (US).

  7. Development of hollow electron beams for proton and ion collimation

    SciTech Connect

    Stancari, G.; Drozhdin, A.I.; Kuznetsov, G.; Shiltsev, V.; Still, D.A.; Valishev, A.; Vorobiev, L.G.; Assmann, R.; Kabantsev, A.; /UC, San Diego

    2010-06-01

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

  8. Micro-patterns fabrication using focused proton beam lithography

    NASA Astrophysics Data System (ADS)

    Cutroneo, M.; Havranek, V.; Mackova, A.; Semian, V.; Torrisi, L.; Calcagno, L.

    2016-03-01

    Proton beam writing technique was recently introduced at 3MV Tandetron accelerator at Nuclear Physics Institute in Rez (Czech Republic). It has been used, to produce three-dimensional (3D) micro-structures in poly(methylmethacrylate) by 2.0 MeV and 2.6 MeV protons micro-beam. Micro-channels (52 μm × 52 μm) have been realized. After chemical etching, the quality of the bottom and side walls of the produced structures in PMMA were analyzed using Scanning Transmission Ion Microscopy (STIM).

  9. A pencil beam approach to proton computed tomography

    SciTech Connect

    Rescigno, Regina Bopp, Cécile; Rousseau, Marc; Brasse, David

    2015-11-15

    Purpose: A new approach to proton computed tomography (pCT) is presented. In this approach, protons are not tracked one-by-one but a beam of particles is considered instead. The elements of the pCT reconstruction problem (residual energy and path) are redefined on the basis of this new approach. An analytical image reconstruction algorithm applicable to this scenario is also proposed. Methods: The pencil beam (PB) and its propagation in matter were modeled by making use of the generalization of the Fermi–Eyges theory to account for multiple Coulomb scattering (MCS). This model was integrated into the pCT reconstruction problem, allowing the definition of the mean beam path concept similar to the most likely path (MLP) used in the single-particle approach. A numerical validation of the model was performed. The algorithm of filtered backprojection along MLPs was adapted to the beam-by-beam approach. The acquisition of a perfect proton scan was simulated and the data were used to reconstruct images of the relative stopping power of the phantom with the single-proton and beam-by-beam approaches. The resulting images were compared in a qualitative way. Results: The parameters of the modeled PB (mean and spread) were compared to Monte Carlo results in order to validate the model. For a water target, good agreement was found for the mean value of the distributions. As far as the spread is concerned, depth-dependent discrepancies as large as 2%–3% were found. For a heterogeneous phantom, discrepancies in the distribution spread ranged from 6% to 8%. The image reconstructed with the beam-by-beam approach showed a high level of noise compared to the one reconstructed with the classical approach. Conclusions: The PB approach to proton imaging may allow technical challenges imposed by the current proton-by-proton method to be overcome. In this framework, an analytical algorithm is proposed. Further work will involve a detailed study of the performances and limitations of

  10. Direct measurements of two photon exchange on lepton-proton elastic scattering using simultaneous electron-positron beams in CLAS

    NASA Astrophysics Data System (ADS)

    Adikaram, Dasuni Kalhari

    The electric (GE) and magnetic ( GM) form factors of the proton are fundamental observables which characterize its charge and magnetization distributions. There are two methods to measure the proton form factors: the Rosenbluth separation method and the polarization transfer technique. However, the ratio of the electric and magnetic form factors measured by those methods significantly disagree at momentum transfer Q2 > 1 GeV2. The most likely explanation of this discrepancy is the inclusion of two-photon exchange (TPE) amplitude contributions to the elastic electron-proton cross section which significantly changes the extraction of GE from the Rosenbluth separation measurement. The Jefferson Lab CLAS TPE experiment determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections. The primary electron beam was used to create an intense bremsstrahlung photon beam. Some of the photons were then converted to a mixed e+/ e- beam which then interacted with a liquid hydrogen target. The e+p and e-p events were detected by the CLAS (CEBAF Large Acceptance Spectrometer). The elastic cross section ratios ((sigma( e+p)/(sigma(e -p)) were measured over a wide range of virtual photon polarization epsilon and Q2. The cross section ratios displayed a strong epsilon dependence at Q2 = 1.45 GeV2. There is no significant Q2 dependence observed at epsilon = 0.45. The results are consistent with a recent measurement at the VEPP-3 lepton storage ring in Novosibirsk and with the hadronic calculation by Blunders, Melnitchouk and Tjon. The hadronic calculation resolves the disagreement between the Rosenbluth separation and polarization transfer extractions of GE/GM at Q2 up to 2 -- 3 GeV2. Applying the GLAS TPE correction to the Rosenbluth cross section measurements significantly decreases the extracted value of GE and brings it into good agreement with the polarization transfer measurement at Q2˜1.75 GeV2. Thus, these

  11. Collimation of laser-produced proton beam

    NASA Astrophysics Data System (ADS)

    Takano, M.; Nagashima, T.; Izumiyama, T.; Gu, Y. J.; Barada, D.; Kong, Q.; Wang, P. X.; Ma, Y. Y.; Wang, W. M.; Kawata, S.

    2016-03-01

    In intense laser plasma interaction for particle acceleration several issues remain to be solved. In this paper we focus on a collimation of ion beam, which is produced by a laser plasma interaction. In this study, the ion beam is collimated by a thin film target. When an intense short pulse laser illuminates a target, target electrons are accelerated, and create an electron cloud that generates a sheath electric field at the target surface. Such the ion acceleration mechanism is called the target normal sheath acceleration (TNSA). The TNSA field would be used for the ion beam collimation by the electric field. We have successfully obtained a collimated beam in our particle-in-cell simulations.

  12. Fermilab Proton Beam for Mu2e

    SciTech Connect

    Syphers, M.J.; /Fermilab

    2009-10-01

    Plans to use existing Fermilab facilities to provide beam for the Muon to Electron Conversion Experiment (Mu2e) are under development. The experiment will follow the completion of the Tevatron Collider Run II, utilizing the beam lines and storage rings used today for antiproton accumulation without considerable reconfiguration. The proposed Mu2e operating scenario is described as well as the accelerator issues being addressed to meet the experimental goals.

  13. Particle selection and beam collimation system for laser-accelerated proton beam therapy.

    PubMed

    Luo, Wei; Fourkal, Eugene; Li, Jinsheng; Ma, Chang-Ming

    2005-03-01

    In a laser-accelerated proton therapy system, the initial protons have broad energy and angular distributions, which are not suitable for direct therapeutic applications. A compact particle selection and collimation device is needed to deliver small pencil beams of protons with desired energy spectra. In this work, we characterize a superconducting magnet system that produces a desired magnetic field configuration to spread the protons with different energies and emitting angles for particle selection. Four magnets are set side by side along the beam axis; each is made of NbTi wires which carry a current density of approximately 10(5) A/cm2 at 4.2 K, and produces a magnetic field of approximately 4.4 T in the corresponding region. Collimation is applied to both the entrance and the exit of the particle selection system to generate a desired proton pencil beam. In the middle of the magnet system, where the magnetic field is close to zero, a particle selection collimator allows only the protons with desired energies to pass through for therapy. Simulations of proton transport in the presence of the magnetic field show that the selected protons have successfully refocused on the beam axis after passing through the magnetic field with the optimal magnet system. The energy spread for any given characteristic proton energy has been obtained. It is shown that the energy spread is a function of the magnetic field strength and collimator size and reaches the full width at half maximum of 25 MeV for 230 MeV protons. Dose distributions have also been calculated with the GEANT3 Monte Carlo code to study the dosimetric properties of the laser-accelerated proton beams for radiation therapy applications. PMID:15839352

  14. Optimization of Extinction Efficiency in the 8-GeV Mu2e Beam Line

    SciTech Connect

    Rakhno, I.L.; Drozhdin, A.I.; Johnstone, C.; Mokhov, N.V.; Prebys, E.; /Fermilab

    2012-05-11

    A muon-to-electron conversion experiment at Fermilab, Mu2e, is being designed to probe for new physics beyond the standard model at mass scales up to 10{sup 4} TeV. For this experiment, the advance in experimental sensitivity will be four orders of magnitude when compared to existing data on charged lepton flavor violation. The muon beam will be produced by delivering a proton beam contained in short 100-ns bunches onto a muon production target, with an inter-bunch separation of about 1700 ns. A critical requirement of the experiment is to ensure a low level of background at the muon detector consistent with the required sensitivity. To meet the sensitivity requirement, protons that reach the target between bunches must be suppressed by an enormous factor, so that an extinction factor, defined as a number of background protons between main bunches per proton in such a bunch, should not exceed 10{sup -9}. This paper describes the advanced beam optics and results of numerical modeling with STRUCT and MARS codes for a beam line with a collimation system that allows us to achieve the experimental extinction factor of one per billion.

  15. Reply to comment on 'Proton beam monitor chamber calibration'.

    PubMed

    Gomà, Carles; Lorentini, Stefano; Meer, David; Safai, Sairos

    2016-09-01

    This reply shows that the discrepancy of about 3% between Faraday cup dosimetry and reference dosimetry using a cylindrical ionization chamber found in Gomà (2014 Phys. Med. Biol. 59 4961-71) seems to be due to an overestimation of the beam quality correction factors tabulated in IAEA TRS-398 for the cylindrical chamber used, rather than to 'unresolved problems with Faraday cup dosimetry', as suggested by Palmans and Vatnitsky (2016 Phys. Med. Biol. 61 6585-93). Furthermore, this work shows that a good agreement between reference dosimetry and Faraday cup dosimetry is possible, provided accurate beam quality correction factors for proton beams are used. The review on W air values presented by Palmans and Vatnitsky is believed to be inaccurate, as it is based on the imprecise assumption of ionization chamber perturbation correction factors in proton beams being equal to unity. PMID:27535895

  16. 9 GeV energy gain in a beam-driven plasma wakefield accelerator

    DOE PAGESBeta

    Litos, M.; Adli, E.; Allen, J. M.; An, W.; Clarke, C. I.; Corde, S.; Clayton, C. E.; Frederico, J.; Gessner, S. J.; Green, S. Z.; et al

    2016-02-15

    An electron beam has gained a maximum energy of 9 GeV per particle in a 1.3 m-long electron beam-driven plasma wakefield accelerator. The amount of charge accelerated in the spectral peak was 28.3 pC, and the root-mean-square energy spread was 5.0%. The mean accelerated charge and energy gain per particle of the 215 shot data set was 115 pC and 5.3 GeV, respectively, corresponding to an acceleration gradient of 4.0 GeV m-1 at the spectral peak. Moreover, the mean energy spread of the data set was 5.1%. Our results are consistent with the extrapolation of the previously reported energy gainmore » results using a shorter, 36 cm-long plasma source to within 10%, evincing a non-evolving wake structure that can propagate distances of over a meter in length. Wake-loading effects were evident in the data through strong dependencies observed between various spectral properties and the amount of accelerated charge.« less

  17. 9 GeV energy gain in a beam-driven plasma wakefield accelerator

    NASA Astrophysics Data System (ADS)

    Litos, M.; Adli, E.; Allen, J. M.; An, W.; Clarke, C. I.; Corde, S.; Clayton, C. E.; Frederico, J.; Gessner, S. J.; Green, S. Z.; Hogan, M. J.; Joshi, C.; Lu, W.; Marsh, K. A.; Mori, W. B.; Schmeltz, M.; Vafaei-Najafabadi, N.; Yakimenko, V.

    2016-03-01

    An electron beam has gained a maximum energy of 9 GeV per particle in a 1.3 m-long electron beam-driven plasma wakefield accelerator. The amount of charge accelerated in the spectral peak was 28.3 pC, and the root-mean-square energy spread was 5.0%. The mean accelerated charge and energy gain per particle of the 215 shot data set was 115 pC and 5.3 GeV, respectively, corresponding to an acceleration gradient of 4.0 GeV m-1at the spectral peak. The mean energy spread of the data set was 5.1%. These results are consistent with the extrapolation of the previously reported energy gain results using a shorter, 36 cm-long plasma source to within 10%, evincing a non-evolving wake structure that can propagate distances of over a meter in length. Wake-loading effects were evident in the data through strong dependencies observed between various spectral properties and the amount of accelerated charge.

  18. Proton-beam technique dates fine wine

    NASA Astrophysics Data System (ADS)

    Dumé, Belle

    2008-10-01

    Nuclear physicists in France have invented a way to authenticate the vintage of rare wine without needing a sommelier's keen nose or even a corkscrew. The technique, which involves firing high-energy protons at wine bottles, can determine how old the bottles are and even where they come from. The new method could help unmask counterfeit wines - a growing problem in the fine-wine industry, where a bottle can sell for thousands of Euros.

  19. Improved beam spot measurements in the 2nd generation proton beam writing system

    NASA Astrophysics Data System (ADS)

    Yao, Yong; van Mourik, Martin W.; Santhana Raman, P.; van Kan, Jeroen A.

    2013-07-01

    Nanosized ion beams (especially proton and helium) play a pivotal role in the field of ion beam lithography and ion beam analysis. Proton beam writing has shown lithographic details down to the 20 nm level, limited by the proton beam spot size. Introducing a smaller spot size will allow smaller lithographic features. Smaller probe sizes, will also drastically improve the spatial resolution for ion beam analysis techniques. Among many other requirements, having an ideal resolution standard, used for beam focusing and a reliable focusing method, is an important pre-requisite for sub-10 nm beam spot focusing. In this paper we present the fabrication processes of a free-standing resolution standard with reduced side-wall projection and high side-wall verticality. The resulting grid is orthogonal (90.0° ± 0.1), has smooth edges with better than 6 nm side-wall projection. The new resolution standard has been used in focusing a 2 MeV H2+ beam in the 2nd generation PBW system at Center for Ion Beam Applications, NUS. The beam size has been characterized using on- and off-axis scanning transmission ion microscopy (STIM) and ion induced secondary electron detection, carried out with a newly installed micro channel plate electron detector. The latter has been shown to be a realistic alternative to STIM measurements, as the drawback of PIN diode detector damage is alleviated. With these improvements we show reproducible beam focusing down to 14 nm.

  20. Environmental and safety issues associated with a 30-GeV proton synchrotron

    NASA Astrophysics Data System (ADS)

    Lessard, E. T.

    1999-06-01

    This paper summarizes activation of materials, radioactive waste, sky-shine radiation, groundwater radioactivity, airborne radioactivity, beam faults, exposure of staff, and the environmental performance indicator for a high-energy synchrotron-accelerator-complex on Long Island, New York. Groundwater contamination is a particularly sensitive area of concern. The Laboratory site is located over an EPA designated sole-source aquifer system and there is significant public concern over 3H in on-site groundwater. This paper is intended to give you information about the environmental impacts of one portion of Laboratory operations: the Alternating Gradient Synchrotron (AGS) complex of accelerators that deliver protons and heavy-ions to the high-energy physics and nuclear physics communities.

  1. CERN antiproton target: Hydrocode analysis of its core material dynamic response under proton beam impact

    NASA Astrophysics Data System (ADS)

    Martin, Claudio Torregrosa; Perillo-Marcone, Antonio; Calviani, Marco; Muñoz-Cobo, José-Luis

    2016-07-01

    Antiprotons are produced at CERN by colliding a 26 GeV /c proton beam with a fixed target made of a 3 mm diameter, 55 mm length iridium core. The inherent characteristics of antiproton production involve extremely high energy depositions inside the target when impacted by each primary proton beam, making it one of the most dynamically demanding among high energy solid targets in the world, with a rise temperature above 2000 °C after each pulse impact and successive dynamic pressure waves of the order of GPa's. An optimized redesign of the current target is foreseen for the next 20 years of operation. As a first step in the design procedure, this numerical study delves into the fundamental phenomena present in the target material core under proton pulse impact and subsequent pressure wave propagation by the use of hydrocodes. Three major phenomena have been identified, (i) the dominance of a high frequency radial wave which produces destructive compressive-to-tensile pressure response (ii) The existence of end-of-pulse tensile waves and its relevance on the overall response (iii) A reduction of 44% in tensile pressure could be obtained by the use of a high density tantalum cladding.

  2. GeV electron beams from a cm-scale accelerator

    SciTech Connect

    Leemans, W.P.; Nagler, B.; Gonsalves, A.J.; Toth, C.; Nakamura,K.; Geddes, C.G.R.; Esarey, E.B.; Schroeder, C.; Hooker, S.M.

    2006-05-04

    GeV electron accelerators are essential to synchrotron radiation facilities and free electron lasers, and as modules for high-energy particle physics. Radio frequency based accelerators are limited to relatively low accelerating fields (10-50 MV/m) and hence require tens to hundreds of meters to reach the multi-GeV beam energies needed to drive radiation sources, and many kilometers to generate particle energies of interest to the frontiers of high-energy physics.Laser wakefield accelerators (LWFA) in which particles are accelerated by the field of a plasma wave driven by an intense laser pulse produce electric fields several orders of magnitude stronger (10-100 GV/m) and so offer the potential of very compact devices. However, until now it has not been possible to maintain the required laser intensity, and hence acceleration, over the several centimeters needed to reach GeV energies.For this reason laser-driven accelerators have to date been limited to the 100 MeV scale. Contrary to predictions that PW-class lasers would be needed to reach GeV energies, here we demonstrate production of a high-quality electron beam with 1 GeV energy by channeling a 40 TW peak power laser pulse in a 3.3 cm long gas-filled capillary discharge waveguide. We anticipate that laser-plasma accelerators based on capillary discharge waveguides will have a major impact on the development of future femtosecond radiation sources such as x-ray free electron lasers and become a standard building block for next generation high-energy accelerators.

  3. Thermal hydraulic studies of spallation target for one-way coupled Indian accelerator driven systems with low energy proton beam

    NASA Astrophysics Data System (ADS)

    Mantha, V.; Mohanty, A. K.; Satyamurthy, P.

    2007-02-01

    BARC has recently proposed a one-way coupled ADS reactor. This reactor requires typically 1 GeV proton beam with 2 mA of current. Approximately 8 kW of heat is deposited in the window of the target. Circulating liquid metal target (lead/lead-bismuth{eutectic) has to extract this heat and this is a critical R&D problem to be solved. At present there are very few accelerators, which can give few mA and high-energy proton beam. However, accelerators with low energy and hundreds of micro-ampere current are commercially available. In view of this, it is proposed in this paper to simulate beam window heating of 8 kW in the target with low-energy proton beam. Detailed thermal analysis in the spallation and window region has been carried out to study the capability of heat extraction by circulating LBE for a typical target loop with a proton beam of 30 MeV energy and current of 0.267 mA. The heat deposition study is carried out using FLUKA code and flow analysis by CFD code. The detailed analysis of this work is presented in this paper.

  4. Beam collimation and energy spectrum compression of laser-accelerated proton beams using solenoid field and RF cavity

    NASA Astrophysics Data System (ADS)

    Teng, J.; Gu, Y. Q.; Zhu, B.; Hong, W.; Zhao, Z. Q.; Zhou, W. M.; Cao, L. F.

    2013-11-01

    This paper presents a new method of laser produced proton beam collimation and spectrum compression using a combination of a solenoid field and a RF cavity. The solenoid collects laser-driven protons efficiently within an angle that is smaller than 12 degrees because it is mounted few millimeters from the target, and collimates protons with energies around 2.3 MeV. The collimated proton beam then passes through a RF cavity to allow compression of the spectrum. Particle-in-cell (PIC) simulations demonstrate the proton beam transport in the solenoid and RF electric fields. Excellent energy compression and collection efficiency of protons are presented. This method for proton beam optimization is suitable for high repetition-rate laser acceleration proton beams, which could be used as an injector for a conventional proton accelerator.

  5. Beam physics of the 8-GeV H-minus linac

    SciTech Connect

    Carneiro, J.-P.; Mustapha, B.; Ostroumov, P.N.; /Argonne

    2008-11-01

    Fermilab is developing the concept and design of an 8-GeV superconducting H-minus linac with the primary mission of increasing the intensity of the Main Injector for the production of neutrino superbeams. The front-end of the linac up to 420 MeV operates at 325 MHz and accelerates beam from the ion source using a room temperature radio-frequency quadrupole followed by short CH type resonators and superconducting spoke resonators. In the high energy section, the acceleration is provided by the International Linear Collider (ILC)-style superconducting elliptical 1.3 GHz cavities. The beam physics for the linac is presented in this paper using two beam dynamics codes: TRACK and ASTRA.

  6. Nuclear Data for Proton Beam Radiotherapy

    SciTech Connect

    Melo Rego, Maria Eugenia de; Carlson, B. V.

    2009-06-03

    The need for a program of work focused on the nuclear data evaluation of charged-particle reactions has arisen recently due to their increasing use in cancer therapy. This project, as part of that program, has as its main goal the selection and comparison of nuclear data for nuclear reactions induced by protons at low to intermediate energies (E<250 MeV). The methodology of selection was based on the data base EXFOR and the compilations of radionuclide production cross sections of N. Sobolevsky. For the purpose of comparison and evaluation, theoretical calculations with the reaction model code EMPIRE-II are being used.

  7. FIDDLING CARBON STRINGS WITH POLARIZED PROTON BEAMS.

    SciTech Connect

    HUANG, H.; KURITA, K.

    2006-05-01

    An innovative polarimeter based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region was first tested in the Brookhaven AGS successfully. CNI Polarimeters were then installed in the AGS and both RHIC rings. The polarimeter consists of ultra-thin carbon targets and silicon strip detectors. The waveform digitizers are used for signal readout, which allows deadtime-less data processing on the fly. Polarimeters are crucial instrumentation for the RHIC spin physics program. This paper summarizes the polarimeter design issues and operation results.

  8. π+ photoproduction on the proton for photon energies from 0.725 to 2.875 GeV

    NASA Astrophysics Data System (ADS)

    Dugger, M.; Ritchie, B. G.; Ball, J. P.; Collins, P.; Pasyuk, E.; Arndt, R. A.; Briscoe, W. J.; Strakovsky, I. I.; Workman, R. L.; Amaryan, M. J.; Anghinolfi, M.; Bagdasaryan, H.; Battaglieri, M.; Bellis, M.; Berman, B. L.; Biselli, A. S.; Bookwalter, C.; Branford, D.; Brooks, W. K.; Burkert, V. D.; Careccia, S. L.; Carman, D. S.; Cole, P. L.; Corvisiero, P.; Crede, V.; Daniel, A.; Dashyan, N.; Vita, R. De; Sanctis, E. De; Deur, A.; Dhamija, S.; Dickson, R.; Djalali, C.; Dodge, G. E.; Doughty, D.; Eugenio, P.; Fedotov, G.; Ficenec, J.; Fradi, A.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Hassall, N.; Heddle, D.; Hicks, K.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Johnstone, J. R.; Joo, K.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, W.; Klein, A.; Klein, F. J.; Kramer, L. H.; Kubarovsky, V.; Kuleshov, S. V.; Kuznetsov, V.; Livingston, K.; Lu, H. Y.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Moreno, B.; Moriya, K.; Nadel-Turonski, P.; Nasseripour, R.; Niccolai, S.; Niculescu, I.; Niroula, M. R.; Osipenko, M.; Ostrovidov, A. I.; Park, S.; Pereira, S. Anefalos; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Raue, B. A.; Ricco, G.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salamanca, J.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Sober, D. I.; Sokhan, D.; Stepanyan, S.; Stepanyan, S. S.; Strauch, S.; Taiuti, M.; Tedeschi, D. J.; Tkachenko, S.; Vineyard, M. F.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Yegneswaran, A.

    2009-06-01

    Differential cross sections for the reaction γp→nπ+ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.725 to 2.875 GeV. Where available, the results obtained here compare well with previously published results for the reaction. Agreement with the SAID and MAID analyses is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been made up to 2.7 GeV. Resonance couplings have been extracted and compared to previous determinations. With the addition of these cross sections to the world data set, significant changes have occurred in the high-energy behavior of the SAID cross-section predictions and amplitudes.

  9. $\\pi^+$ photoproduction on the proton for photon energies from 0.725 to 2.875 GeV

    SciTech Connect

    Dugger, Michael; Ritchie, Barry; Ball, J.P.; Ball, Jacques; Collins, Patrick; Pasyuk, E.; Arndt, Richard; Briscoe, William; Strakovski, Igor; Workman, Ron

    2009-06-01

    Differential cross sections for the reaction $\\gamma p \\to n \\pi^+$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.725 to 2.875 GeV. Where available, the results obtained here compare well with previously published results for the reaction. Agreement with the SAID and MAID analyses is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been made up to 2.7 GeV. Resonance couplings have been extracted and compared to previous determinations. With the addition of these cross sections to the world data set, significant changes have occurred in the high-energy behavior of the SAID cross-section predictions and amplitudes.

  10. pi0 photoproduction on the proton for photon energies from 0.675 to 2.875-GeV

    SciTech Connect

    Michael Dugger; Barry Ritchie; Jacques Ball; Patrick Collins; Evgueni Pasyuk; Richard Arndt; William Briscoe; Igor Strakovski; Ron Workman; Gary Adams; Moscov Amaryan; Pawel Ambrozewicz; Eric Anciant; Marco Anghinolfi; Burin Asavapibhop; G. Asryan; Gerard Audit; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Nathan Baltzell; Steve Barrow; Marco Battaglieri; Kevin Beard; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Nicola Bianchi; Angela Biselli; Billy Bonner; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Bryan Carnahan; Shifeng Chen; Philip Cole; Alan Coleman; Philip Coltharp; Dieter Cords; Pietro Corvisiero; Donald Crabb; Hall Crannell; John Cummings; Enzo De Sanctis; Raffaella De Vita; Pavel Degtiarenko; Haluk Denizli; Lawrence Dennis; Alexandre Deur; Kahanawita Dharmawardane; Kalvir Dhuga; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; P. Dragovitsch; Steven Dytman; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; A. Empl; Paul Eugenio; Renee Fatemi; Gleb Fedotov; Gerald Feldman; Robert Feuerbach; John Ficenec; Tony Forest; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Ralf Gothe; Keith Griffioen; Michel Guidal; Matthieu Guillo; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Rafael Hakobyan; John Hardie; D. Heddle; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; J. Hu; Marco Huertas; Charles Hyde; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Kui Kim; Kinney Kim; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mike Klusman; Mikhail Kossov; Zebulun Krahn; Laird Kramer; Valery Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Viacheslav Kuznetsov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ana Lima; Kenneth Livingston; K. Lukashin; Joseph Manak; Claude Marchand; Leonard Maximon; Simeon McAleer; Bryan McKinnon; John McNabb; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; Valeria Muccifora; James Mueller; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Grant O'Rielly; Mikhail Osipenko; Alexander Ostrovidov; K Park; Craig Paterson; Sasha Philips; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; S. Pozdniakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Liming Qin; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; David Rowntree; Philip Rubin; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Aziz Shafi; Youri Sharabian; J. Shaw; Sebastio Simionatto; Alexander Skabelin; Elton Smith; Lee Smith; Daniel Sober; M. Spraker; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; Simon Taylor; David Tedeschi; Ulrike Thoma; R. Thompson; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Xue kai Wang; Lawrence Weinstein; Henry Weller; Dennis Weygand; M. Williams; Elliott Wolin; M.H. Wood; A. Yegneswaran; Jae-Chul Yun; Lorenzo Zana; Jixie Zhang

    2007-07-23

    Differential cross sections for the reaction $\\gamma p \\to p \\pi^0$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.675 to 2.875 GeV. The results reported here possess greater accuracy in the absolute normalization than previous measurements. They disagree with recent CB-ELSA measurements for the process at forward scattering angles. Agreement with the SAID and MAID fits is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been extended to 3 GeV. Resonance couplings have been extracted and compared to previous determinations.

  11. EPR/alanine dosimetry for two therapeutic proton beams

    NASA Astrophysics Data System (ADS)

    Marrale, Maurizio; Carlino, Antonio; Gallo, Salvatore; Longo, Anna; Panzeca, Salvatore; Bolsi, Alessandra; Hrbacek, Jan; Lomax, Tony

    2016-02-01

    In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtained with other dosimetric techniques (such as Markus chamber and diode detector). This analysis showed that the dosimeter response is independent of collimator diameter if this is larger than or equal to 10 mm. The other beam is characterized by an active spot-scanning technique, the Gantry1 beam line (maximum energy 230 MeV), and is used to treat deep-seated tumors. The dose linearity of alanine response in the clinical dose range was tested and the alanine dose response at selected locations in depth was measured and compared with the TPS planned dose in a quasi-clinical scenario. The alanine response was found to be linear in the dose in the clinical explored range (from 10 to 70 Gy). Furthermore, a depth dose profile in a quasi-clinical scenario was measured and compared to the dose computed by the Treatment Planning System PSIPLAN. The comparison of calibrated proton alanine measurements and TPS dose shows a difference under 1% in the SOBP and a "quenching" effect up to 4% in the distal part of SOBP. The positive dosimetric characteristics of the alanine pellets confirm the feasibility to use these detectors for "in vivo" dosimetry in clinical proton beams.

  12. Characterization of uniform scanning proton beams with analytical models

    NASA Astrophysics Data System (ADS)

    Demez, Nebi

    Tissue equivalent phantoms have an important place in radiation therapy planning and delivery. They have been manufactured for use in conventional radiotherapy. Their tissue equivalency for proton beams is currently in active investigation. The Bragg-Kleeman rule was used to calculate water equivalent thickness (WET) for available tissue equivalent phantoms from CIRS (Norfolk, VA, USA). WET's of those phantoms were also measured using proton beams at Hampton University Proton Therapy Institute (HUPTI). WET measurements and calculations are in good agreement within ˜1% accuracy except for high Z phantoms. Proton beams were also characterized with an analytical proton dose calculation model, Proton Loss Model (PLM) [26], to investigate protons interactions in water and those phantoms. Depth-dose and lateral dose profiles of protons in water and in those phantoms were calculated, measured, and compared. Water Equivalent Spreadness (WES) was also investigated for those phantoms using the formula for scattering power ratio. Because WES is independent of incident energy of protons, it is possible to estimate spreadness of protons in different media by just knowing WES. Measurements are usually taken for configuration of the treatment planning system (TPS). This study attempted to achieve commissioning data for uniform scanning proton planning with analytical methods, PLM, which have been verified with published measurements and Monte Carlo calculations. Depth doses and lateral profiles calculated by PLM were compared with measurements via the gamma analysis method. While gamma analysis shows that depth doses are in >90% agreement with measured depth doses, the agreement falls to <80% for some lateral profiles. PLM data were imported into the TPS (PLM-TPS). PLM-TPS was tested with different patient cases. The PLM-TPS treatment plans for 5 prostate cases show acceptable agreement. The Planning Treatment Volume (PTV) coverage was 100 % with PLM-TPS except for one case in

  13. Longitudinal spin transfer to {lambda} and {lambda} hyperons in polarized proton-proton collisions at {radical}(s)=200 GeV

    SciTech Connect

    Abelev, B. I.; Barannikova, O.; Betts, R. R.; Garcia-Solis, E. J.; Hofman, D. J.; Hollis, R. S.; Iordanova, A.; Kauder, K.; Suarez, M. C.; Aggarwal, M. M.; Bhati, A. K.; Kumar, L.; Pruthi, N. K.; Ahammed, Z.; Chattopadhyay, S.; Dutta Mazumdar, M. R.; Ganti, M. S.; Ghosh, P.; Mohanty, B.; Nayak, T. K.

    2009-12-01

    The longitudinal spin transfer, D{sub LL}, from high energy polarized protons to {lambda} and {lambda} hyperons has been measured for the first time in proton-proton collisions at {radical}(s)=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. The measurements cover pseudorapidity, {eta}, in the range |{eta}|<1.2 and transverse momenta, p{sub T}, up to 4 GeV/c. The longitudinal spin transfer is found to be D{sub LL}=-0.03{+-}0.13(stat){+-}0.04(syst) for inclusive {lambda} and D{sub LL}=-0.12{+-}0.08(stat){+-}0.03(syst) for inclusive {lambda} hyperons with <{eta}>=0.5 and =3.7 GeV/c. The dependence on {eta} and p{sub T} is presented.

  14. Longitudinal Spin Transfer to Lambda and Lambda bar Hyperons in Polarized Proton-Proton Collisions at sqrt s = 200 GeV

    SciTech Connect

    STAR Collaboration; Abelev, Betty

    2010-07-05

    The longitudinal spin transfer, D{sub LL}, from high energy polarized protons to {Lambda} and {bar {Lambda}} hypersons has been measured for the first time in proton-proton collisions at {radical}s = 200 GeV with the STAR detector at RHIC. The measurements cover pseudorapidity, {eta}, in the range |{eta}| < 1.2 and transverse momenta, p{sub T}, up to 4 GeV/c. The longitudinal spin transfer is found to be D{sub LL} = -0.03{+-}0.13(stat){+-}0.04(syst) for inclusive {Lambda} and D{sub LL} = -0.12{+-}0.08(stat){+-}0.03(syst) for inclusive {bar {Lambda}} hyperons with <{eta}> = 0.5 and = 3.7 GeV/c. The dependence on {eta} and p{sub T} is presented.

  15. Longitudinal spin transfer to {Lambda} and {bar Lambda} hyperons in polarized proton-proton collisions at {radical}{ovr s} = 200 GeV.

    SciTech Connect

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Anderson, B. D.; Bridgeman, A.; Krueger, K.; Spinka, H. M.; Underwood, D. G.; STAR Collaboration

    2009-01-01

    The longitudinal spin transfer, D{sub LL}, from high energy polarized protons to {Lambda} and {bar {Lambda}} hyperons has been measured for the first time in proton-proton collisions at {radical}s = 200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. The measurements cover pseudorapidity, {eta}, in the range |{eta}| < 1.2 and transverse momenta, p{sub T}, up to 4 GeV/c. The longitudinal spin transfer is found to be D{sub LL} = -0.03 {+-} 0.13(stat) {+-} 0.04(syst) for inclusive {Lambda} and D{sub LL} = -0.12 {+-} 0.08(stat) {+-} 0.03(syst) for inclusive {bar {Lambda}} hyperons with {eta} = 0.5 and p{sub T} =3.7 GeV/c. The dependence on {eta} and p{sub T} is presented.

  16. Measurement of the cosmic-ray antiproton-to-proton abundance ratio between 4 and 50 GeV.

    PubMed

    Beach, A S; Beatty, J J; Bhattacharyya, A; Bower, C; Coutu, S; DuVernois, M A; Labrador, A W; McKee, S; Minnick, S A; Müller, D; Musser, J; Nutter, S; Schubnell, M; Swordy, S; Tarlé, G; Tomasch, A

    2001-12-31

    We present a new measurement of the antiproton-to-proton abundance ratio, pbar/p, in the cosmic radiation. The HEAT-pbar instrument, a balloon borne magnet spectrometer with precise rigidity and multiple energy loss measurement capability, was flown successfully in Spring 2000, at an average atmospheric depth of 7.2 g/cm(2). A total of 71 antiprotons were identified above the vertical geomagnetic cutoff rigidity of 4.2 GV. The highest measured proton energy was 81 GeV. We find that the pbar/p abundance ratio agrees with that expected from a purely secondary origin of antiprotons produced by primary protons with a standard soft energy spectrum. PMID:11800867

  17. Stability Issues of the Mu2e Proton Beam

    SciTech Connect

    Ng, K.Y.; /Fermilab

    2009-05-01

    Stability issues of the mu2e proton beam are discussed. These include space-charge distortion of bunch shape, microwave instabilities, mode-coupling instabilities, head-tail instabilities, as well as electron-cloud effects. We have studied several beam stability issues of the proton beam heading to the target for the mu2e experiment. We find bunch-shape distortions driven by the space charge force is reasonably small, and longitudinal microwave instability will unlikely to occur. Electron-cloud buildup, with density up to {rho}{sub e} {approx} 2 x 10{sup 12} m{sup -3} in the Accumulator, can probably drive head-tail instabilities. However, these, together with the instabilities driven by the resistive-wall impedance can be avoided by restricting the chromaticity to larger than {approx} 0.2. TMCI will not occur even when the electron-cloud wake is included.

  18. The generation of proton beams in two-ribbon flares

    NASA Technical Reports Server (NTRS)

    Martens, P. C. H.

    1988-01-01

    It is shown that, in the current sheet at the top of the arcade of postflare loops in a two-ribbon solar flare, particle beams are generated by direct electric-field acceleration. The acceleration process is completely collisionless and is limited only by the gyromotion along the component of the magnetic field perpendicular to the sheet. This mechanism is similar to the particle acceleration in the geomagnetic tail. Neutral beams emanate from the sheet with almost zero pitch angle, making protons the main carriers of the beam energy. Approximately 10 to the 35th protons/sec are generated with a typical energy of 200 keV. Their energy distribution is a single power law, with an upper and lower energy cut-off. Such a population is capable of simultaneously generating the observed impulsive-phase hard X-rays and the gamma rays.

  19. Self-pinched transport of an intense proton beam

    SciTech Connect

    Ottinger, P. F.; Young, F. C.; Stephanakis, S. J.; Rose, D. V.; Neri, J. M.; Weber, B. V.; Myers, M. C.; Hinshelwood, D. D.; Mosher, D.; Olson, C. L.

    2000-01-01

    Ion beam self-pinched transport (SPT) experiments have been carried out using a 1.1-MeV, 100-kA proton beam. A Rutherford scattering diagnostic and a LiF nuclear activation diagnostic measured the number of protons within a 5 cm radius at 50 cm into the transport region that was filled with low-pressure helium. Time-integrated signals from both diagnostics indicate self-pinching of the ion beam in a helium pressure window between 35 and 80 mTorr. Signals from these two diagnostics are consistent with ballistic transport at pressures above and below this SPT pressure window. Interferometric measurements of electron densities during beam injection into vacuum are consistent with ballistic transport with co-moving electrons. Interferometric measurements for beam injection into helium show that the electron density increases quadratically with pressure through the SPT window and roughly linearly with pressure above the SPT window. The ionization fraction of the helium plateaus at about 1.5% for pressures above 80 mTorr. In the SPT window, the electron density is 3 to 20 times the beam density. Numerical simulations of these beam transport experiments produce results that are in qualitative agreement with the experimental measurements. (c) 2000 American Institute of Physics.

  20. Dose error analysis for a scanned proton beam delivery system

    NASA Astrophysics Data System (ADS)

    Coutrakon, G.; Wang, N.; Miller, D. W.; Yang, Y.

    2010-12-01

    All particle beam scanning systems are subject to dose delivery errors due to errors in position, energy and intensity of the delivered beam. In addition, finite scan speeds, beam spill non-uniformities, and delays in detector, detector electronics and magnet responses will all contribute errors in delivery. In this paper, we present dose errors for an 8 × 10 × 8 cm3 target of uniform water equivalent density with 8 cm spread out Bragg peak and a prescribed dose of 2 Gy. Lower doses are also analyzed and presented later in the paper. Beam energy errors and errors due to limitations of scanning system hardware have been included in the analysis. By using Gaussian shaped pencil beams derived from measurements in the research room of the James M Slater Proton Treatment and Research Center at Loma Linda, CA and executing treatment simulations multiple times, statistical dose errors have been calculated in each 2.5 mm cubic voxel in the target. These errors were calculated by delivering multiple treatments to the same volume and calculating the rms variation in delivered dose at each voxel in the target. The variations in dose were the result of random beam delivery errors such as proton energy, spot position and intensity fluctuations. The results show that with reasonable assumptions of random beam delivery errors, the spot scanning technique yielded an rms dose error in each voxel less than 2% or 3% of the 2 Gy prescribed dose. These calculated errors are within acceptable clinical limits for radiation therapy.

  1. Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

    SciTech Connect

    Ilkyoung Shin, Todd Satogata, Shahid Ahmed, Slawomir Bogacz, Mircea Stirbet, Haipeng Wang, Yan Wang, Byung Yunn, Ryan Bodenstein

    2012-07-01

    Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

  2. The Project-X 3 GeV Beam Distribution System

    SciTech Connect

    Champion, M.S.; Johnson, D.E.; Klebaner, A.L.; Solyak, N.; Yakovlev, V.P.; Awida, M.H.; Gonin, I.V.; /Fermilab

    2012-05-01

    In the Project X facility a 3 GeV H{sup -} CW beam is delivered to three users, simultaneously. This will be accomplished by selectively filling appropriate RF buckets at the front end of the linac then utilizing a RF splitter to transversely separate the bunches vertically to three different target halls. A compact TE{sub 113} squashed-wall superconducting RF cavity has been proposed to produce the initial vertical deflection. The transport line optics, cavity design parameters, and cryogenic system requirements is presented.

  3. Macroparticle simulation studies of a proton beam haloexperiment

    SciTech Connect

    Qiang, J.; Colestock, P.L.; Gilpatrick, D.; Smith, H.V.; Wangler,T.P.; Schulze, M.E.

    2002-09-12

    We report macroparticle simulations for comparison withmeasured results from a proton beam-halo experiment in a 52-quadrupoleperiodic-focusing channel. An important issue is that the inputphase-space distribution is not experimentally known. Three differentinitial distributions with different shapes predict different beamprofiles in the transport system. Simulations have been fairly successfulin reproducing the core of the measured matched-beam profiles and thetrend of emittance growth as a function of mismatch factor, butunderestimate the growth rate of halo and emittance for mismatched beams.In this study, we find that knowledge of the Courant-Snyder parametersand emittances of the input beam is not sufficient for reliableprediction of the halo. Input distributions iwth greater population inthe tails produce larger rates of emittance growth, a result that isqualitatively consistent with the particle-core model of halo formationin mismatched beams.

  4. Preliminary results of proton beam characterization for a facility of broad beam in vitro cell irradiation

    NASA Astrophysics Data System (ADS)

    Wéra, A.-C.; Donato, K.; Michiels, C.; Jongen, Y.; Lucas, S.

    2008-05-01

    The interaction of charged particles with living matter needs to be well understood for medical applications. Particularly, it is useful to study how ion beams interact with tissues in terms of damage, dose released and dose rate. One way to evaluate the biological effects induced by an ion beam is by the irradiation of cultured cells at a particle accelerator, where cells can be exposed to different ions at different energies and flux. In this paper, we report the first results concerning the characterization of a broad proton beam obtained with our 2 MV tandem accelerator. For broad beam in vitro cell irradiation, the beam has to be stable over time, uniform over a ∼0.5 cm2 surface, and a dose rate ranging from 0.1 to 10 Gy/min must be achievable. Results concerning the level of achievement of these requirements are presented in this paper for a 1 MeV proton beam.

  5. New measurement of the antiproton-to-proton flux ratio up to 100 GeV in the cosmic radiation.

    PubMed

    Adriani, O; Barbarino, G C; Bazilevskaya, G A; Bellotti, R; Boezio, M; Bogomolov, E A; Bonechi, L; Bongi, M; Bonvicini, V; Bottai, S; Bruno, A; Cafagna, F; Campana, D; Carlson, P; Casolino, M; Castellini, G; De Pascale, M P; De Rosa, G; Fedele, D; Galper, A M; Grishantseva, L; Hofverberg, P; Leonov, A; Koldashov, S V; Krutkov, S Y; Kvashnin, A N; Malvezzi, V; Marcelli, L; Menn, W; Mikhailov, V V; Minori, M; Mocchiutti, E; Nagni, M; Orsi, S; Osteria, G; Papini, P; Pearce, M; Picozza, P; Ricci, M; Ricciarini, S B; Simon, M; Sparvoli, R; Spillantini, P; Stozhkov, Y I; Taddei, E; Vacchi, A; Vannuccini, E; Vasilyev, G; Voronov, S A; Yurkin, Y T; Zampa, G; Zampa, N; Zverev, V G

    2009-02-01

    A new measurement of the cosmic-ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a tenfold improvement in statistics with respect to all previously published data. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e.g., dark matter particle annihilations. PMID:19257498

  6. A search for proton beams during flares on AU Microscopii

    NASA Technical Reports Server (NTRS)

    Robinson, R. D.; Carpenter, K. G.; Woodgate, B. E.; Maran, S. P.

    1993-01-01

    We report the results of a coordinated observing campaign on the active M dwarf star AU Mic. The purpose of the campaign was to search for evidence of proton beams during the impulsive phase of stellar flares and to determine whether the energy contained in these beams represented a significant fraction of the energy budget of the flare. During a total of 3.5 hr of monitoring a small flare was observed simultaneously by the HST, IUE, and the AAT. This event, which had a total optical + UV emission of 1.3 x 10 exp 32 ergs, occurred during the decay phase of a much larger event and showed no evidence for a proton beam with an energy greater than a few times 10 exp 29 ergs/s. This is comparable to the maximum energy flux released by the flare, though this energy release rate must occur over a time interval much shorter than that of the impulsive phase itself. We conclude that the proton beams may be capable of transporting some energy during the impulsive phase of a flare, but that they are unlikely to be the major contributor, at least for this particular event.

  7. Study of a national 2-GeV continuous beam electron accelerator

    SciTech Connect

    Cho, Y.; Holt, R.J.; Jackson, H.E.; Khoe, T.K.; Mavrogenes, G.S.

    1980-08-01

    Current trends in research in medium energy physics with electromagnetic probes are reviewed briefly and design objectives are proposed for a continuous beam 2 GeV electron accelerator. Various types of accelerator systems are discussed and exploratory designs developed for two concepts, the linac-stretcher ring and a double-sided microtron system. Preliminary cost estimates indicate that a linac-ring system which meets all the design objectives with the exception of beam quality and uses state-of-the-art technology can be built for approximately $29 million. However, the double-sided microtron shows promise for development into a substantially less expensive facility meeting all design objectives. Its technical feasibility remains to be established. Specific areas requiring additional engineering studies are discussed, and current efforts at Argonne and elsewhere are identified.

  8. Proton beam generation of oblique whistler waves

    NASA Technical Reports Server (NTRS)

    Wong, H. K.; Goldstein, M. L.

    1988-01-01

    It is known that ion beams are capable of generating whistler waves that propagate parallel to the mean magnetic field. Such waves may have been observed both upstream of the earth's bow shock and in the vicinity of comets. Previous analyses are extended to include propagation oblique to the mean magnetic field. The instability is generated by the perpendicular component of free energy in the ions, which can arise either via a temperature anisotropy or via a gyrating distribution. In the former case, the generation of whistler waves is confined to a fairly narrow cone of propagation directions centered about parallel propagation; in the latter case, the maximum growth of the instability can occur at fairly large obliquities (theta equal to about 50 deg).

  9. Demonstration of self-truncated ionization injection for GeV electron beams

    PubMed Central

    Mirzaie, M.; Li, S.; Zeng, M.; Hafz, N. A. M.; Chen, M.; Li, G. Y.; Zhu, Q. J.; Liao, H.; Sokollik, T.; Liu, F.; Ma, Y. Y.; Chen, L.M.; Sheng, Z. M.; Zhang, J.

    2015-01-01

    Ionization-induced injection mechanism was introduced in 2010 to reduce the laser intensity threshold for controllable electron trapping in laser wakefield accelerators (LWFA). However, usually it generates electron beams with continuous energy spectra. Subsequently, a dual-stage target separating the injection and acceleration processes was regarded as essential to achieve narrow energy-spread electron beams by ionization injection. Recently, we numerically proposed a self-truncation scenario of the ionization injection process based upon overshooting of the laser-focusing in plasma which can reduce the electron injection length down to a few hundred micrometers, leading to accelerated beams with extremely low energy-spread in a single-stage. Here, using 100 TW-class laser pulses we report experimental observations of this injection scenario in centimeter-long plasma leading to the generation of narrow energy-spread GeV electron beams, demonstrating its robustness and scalability. Compared with the self-injection and dual-stage schemes, the self-truncated ionization injection generates higher-quality electron beams at lower intensities and densities, and is therefore promising for practical applications. PMID:26423136

  10. Demonstration of self-truncated ionization injection for GeV electron beams.

    PubMed

    Mirzaie, M; Li, S; Zeng, M; Hafz, N A M; Chen, M; Li, G Y; Zhu, Q J; Liao, H; Sokollik, T; Liu, F; Ma, Y Y; Chen, L M; Sheng, Z M; Zhang, J

    2015-01-01

    Ionization-induced injection mechanism was introduced in 2010 to reduce the laser intensity threshold for controllable electron trapping in laser wakefield accelerators (LWFA). However, usually it generates electron beams with continuous energy spectra. Subsequently, a dual-stage target separating the injection and acceleration processes was regarded as essential to achieve narrow energy-spread electron beams by ionization injection. Recently, we numerically proposed a self-truncation scenario of the ionization injection process based upon overshooting of the laser-focusing in plasma which can reduce the electron injection length down to a few hundred micrometers, leading to accelerated beams with extremely low energy-spread in a single-stage. Here, using 100 TW-class laser pulses we report experimental observations of this injection scenario in centimeter-long plasma leading to the generation of narrow energy-spread GeV electron beams, demonstrating its robustness and scalability. Compared with the self-injection and dual-stage schemes, the self-truncated ionization injection generates higher-quality electron beams at lower intensities and densities, and is therefore promising for practical applications. PMID:26423136

  11. First proton-proton collisions at the LHC as observed with the ALICE detector: measurement of the charged-particle pseudorapidity density at sqrt{s}=900 GeV

    NASA Astrophysics Data System (ADS)

    Aamodt, K.; Abel, N.; Abeysekara, U.; Abrahantes Quintana, A.; Acero, A.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agocs, A. G.; Aguilar Salazar, S.; Ahammed, Z.; Ahmad, A.; Ahmad, N.; Ahn, S. U.; Akimoto, R.; Akindinov, A.; Aleksandrov, D.; Alessandro, B.; Alfaro Molina, R.; Alici, A.; Almaráz Aviña, E.; Alme, J.; Alt, T.; Altini, V.; Altinpinar, S.; Andrei, C.; Andronic, A.; Anelli, G.; Angelov, V.; Anson, C.; Antičić, T.; Antinori, F.; Antinori, S.; Antipin, K.; Antończyk, D.; Antonioli, P.; Anzo, A.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arceo, R.; Arend, A.; Armesto, N.; Arnaldi, R.; Aronsson, T.; Arsene, I. C.; Asryan, A.; Augustinus, A.; Averbeck, R.; Awes, T. C.; Äystö, J.; Azmi, M. D.; Bablok, S.; Bach, M.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Baldit, A.; Bán, J.; Barbera, R.; Barnaföldi, G. G.; Barnby, L.; Barret, V.; Bartke, J.; Barile, F.; Basile, M.; Basmanov, V.; Bastid, N.; Bathen, B.; Batigne, G.; Batyunya, B.; Baumann, C.; Bearden, I. G.; Becker, B.; Belikov, I.; Bellwied, R.; Belmont-Moreno, E.; Belogianni, A.; Benhabib, L.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdermann, E.; Berdnikov, Y.; Betev, L.; Bhasin, A.; Bhati, A. K.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Bimbot, L.; Biolcati, E.; Blanc, A.; Blanco, F.; Blanco, F.; Blau, D.; Blume, C.; Boccioli, M.; Bock, N.; Bøgdanov, A.; Bøggild, H.; Bogolyubsky, M.; Bohm, J.; Boldizsár, L.; Bombara, M.; Bombonati, C.; Bondila, M.; Borel, H.; Borshchov, V.; Bortolin, C.; Bose, S.; Bosisio, L.; Bossú, F.; Botje, M.; Böttger, S.; Bourdaud, G.; Boyer, B.; Braun, M.; Braun-Munzinger, P.; Bravina, L.; Bregant, M.; Breitner, T.; Bruckner, G.; Brun, R.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bugaev, K.; Buncic, P.; Busch, O.; Buthelezi, Z.; Caffarri, D.; Cai, X.; Caines, H.; Camacho, E.; Camerini, P.; Campbell, M.; Canoa Roman, V.; Capitani, G. P.; Cara Romeo, G.; Carena, F.; Carena, W.; Carminati, F.; Casanova Díaz, A.; Caselle, M.; Castillo Castellanos, J.; Castillo Hernandez, J. F.; Catanescu, V.; Cattaruzza, E.; Cavicchioli, C.; Cerello, P.; Chambert, V.; Chang, B.; Chapeland, S.; Charpy, A.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chiavassa, E.; Chibante Barroso, V.; Chinellato, D. D.; Chochula, P.; Choi, K.; Chojnacki, M.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chuman, F.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Cobanoglu, O.; Coffin, J.-P.; Coli, S.; Colla, A.; Conesa Balbastre, G.; Conesa Del Valle, Z.; Conner, E. S.; Constantin, P.; Contin, G.; Contreras, J. G.; Corrales Morales, Y.; Cormier, T. M.; Cortese, P.; Cortés Maldonado, I.; Cosentino, M. R.; Costa, F.; Cotallo, M. E.; Crescio, E.; Crochet, P.; Cuautle, E.; Cunqueiro, L.; Cussonneau, J.; Dainese, A.; Dalsgaard, H. H.; Danu, A.; Das, I.; Das, S.; Dash, A.; Dash, S.; de Barros, G. O. V.; de Caro, A.; de Cataldo, G.; de Cuveland, J.; de Falco, A.; de Gaspari, M.; de Groot, J.; de Gruttola, D.; de Haas, A. P.; de Marco, N.; de Rooij, R.; de Pasquale, S.; de Vaux, G.; Delagrange, H.; Dellacasa, G.; Deloff, A.; Demanov, V.; Dénes, E.; Deppman, A.; D'Erasmo, G.; Derkach, D.; Devaux, A.; di Bari, D.; di Giglio, C.; di Liberto, S.; di Mauro, A.; di Nezza, P.; Dialinas, M.; Díaz, L.; Díaz, R.; Dietel, T.; Ding, H.; Divià, R.; Djuvsland, Ø.; Do Amaral Valdiviesso, G.; Dobretsov, V.; Dobrin, A.; Dobrowolski, T.; Dönigus, B.; Domínguez, I.; Don, D. M. M.; Dordic, O.; Dubey, A. K.; Dubuisson, J.; Ducroux, L.; Dupieux, P.; Dutta Majumdar, A. K.; Dutta Majumdar, M. R.; Elia, D.; Emschermann, D.; Enokizono, A.; Espagnon, B.; Estienne, M.; Evans, D.; Evrard, S.; Eyyubova, G.; Fabjan, C. W.; Fabris, D.; Faivre, J.; Falchieri, D.; Fantoni, A.; Fasel, M.; Fearick, R.; Fedunov, A.; Fehlker, D.; Fekete, V.; Felea, D.; Fenton-Olsen, B.; Feofilov, G.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Ferretti, R.; Figueredo, M. A. S.; Filchagin, S.; Fini, R.; Fionda, F. M.; Fiore, E. M.; Floris, M.; Fodor, Z.; Foertsch, S.; Foka, P.; Fokin, S.; Formenti, F.; Fragiacomo, E.; Fragkiadakis, M.; Frankenfeld, U.; Frolov, A.; Fuchs, U.; Furano, F.; Furget, C.; Fusco Girard, M.; Gaardhøje, J. J.; Gadrat, S.; Gagliardi, M.; Gago, A.; Gallio, M.; Ganoti, P.; Ganti, M. S.; Garabatos, C.; Garc, C.; Gebelein, J.; Gemme, R.; Germain, M.; Gheata, A.; Gheata, M.; Ghidini, B.; Ghosh, P.; Giraudo, G.; Giubellino, P.; Gladysz-Dziadus, E.; Glasow, R.; Glässel, P.; Glenn, A.; Gomez, R.; González Santos, H.; González-Trueba, L. H.; González-Zamora, P.; Gorbunov, S.; Gorbunov, Y.; Gotovac, S.; Gottschlag, H.; Grabski, V.; Grajcarek, R.

    2010-01-01

    On 23rd November 2009, during the early commissioning of the CERN Large Hadron Collider (LHC), two counter-rotating proton bunches were circulated for the first time concurrently in the machine, at the LHC injection energy of 450 GeV per beam. Although the proton intensity was very low, with only one pilot bunch per beam, and no systematic attempt was made to optimize the collision optics, all LHC experiments reported a number of collision candidates. In the ALICE experiment, the collision region was centred very well in both the longitudinal and transverse directions and 284 events were recorded in coincidence with the two passing proton bunches. The events were immediately reconstructed and analyzed both online and offline. We have used these events to measure the pseudorapidity density of charged primary particles in the central region. In the range | η|<0.5, we obtain d N ch/d η=3.10±0.13(stat.)±0.22(syst.) for all inelastic interactions, and d N ch/d η=3.51±0.15(stat.)±0.25(syst.) for non-single diffractive interactions. These results are consistent with previous measurements in proton-antiproton interactions at the same centre-of-mass energy at the CERN Sp overline{p} S collider. They also illustrate the excellent functioning and rapid progress of the LHC accelerator, and of both the hardware and software of the ALICE experiment, in this early start-up phase.

  12. Transverse Beam Spin Asymmetries in Forward-Angle Elastic Electron-Proton Scattering

    SciTech Connect

    David Armstrong; Francois Arvieux; Razmik Asaturyan; Todd Averett; Stephanie Bailey; Guillaume Batigne; Douglas Beck; Elizabeth Beise; Jay Benesch; Louis Bimbot; James Birchall; Angela Biselli; Peter Bosted; Elodie Boukobza; Herbert Breuer; Roger Carlini; Robert Carr; Nicholas Chant; Yu-Chiu Chao; Swapan Chattopadhyay; Russell Clark; Silviu Covrig; Anthony Cowley; Daniel Dale; Charles Davis; Willie Falk; John Finn; Tony Forest; Gregg Franklin; Christophe Furget; David Gaskell; Joseph Grames; Keith Griffioen; Klaus Grimm; Benoit Guillon; Hayko Guler; Lars Hannelius; Richard HASTY; Alice Hawthorne Allen; Tanja Horn; Kathleen Johnston; Mark Jones; Peter Kammel; Reza Kazimi; Paul King; Ameya Kolarkar; Elie Korkmaz; Wolfgang Korsch; Serge Kox; Joachim Kuhn; Jeff Lachniet; Lawrence Lee; Jason Lenoble; Eric Liatard; Jianglai Liu; Berenice Loupias; Allison Lung; Dominique Marchand; Jeffery Martin; Kenneth McFarlane; David McKee; Robert McKeown; Fernand Merchez; Hamlet Mkrtchyan; Bryan Moffit; M. Morlet; Itaru Nakagawa; Kazutaka Nakahara; Retief Neveling; Silvia Niccolai; S. Ong; Shelley Page; Vassilios Papavassiliou; Stephen Pate; Sarah Phillips; Mark Pitt; Benard Poelker; Tracy Porcelli; Gilles Quemener; Brian Quinn; William Ramsay; Aamer Rauf; Jean-Sebastien Real; Julie Roche; Philip Roos; Gary Rutledge; Jeffery Secrest; Neven Simicevic; Gregory Smith; Damon Spayde; Samuel Stepanyan; Marcy Stutzman; Vince Sulkosky; Vincent Sulkosky; Vince Sulkosky; Vincent Sulkosky; Vardan Tadevosyan; Raphael Tieulent; Jacques Van de Wiele; Willem van Oers; Eric Voutier; William Vulcan; Glen Warren; Steven Wells; Steven Williamson; Stephen Wood; Chen Yan; Junho Yun; Valdis Zeps

    2007-08-01

    We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely-polarized 3 GeV electrons from unpolarized protons at Q^2 values of 0.15 and 0.25 (GeV/c)^2 with results of A_n = -4.06 +- 0.99(stat) +- 0.63(syst) and A_n = -4.82 +- 1.87(stat) +- 0.98(syst) ppm. These results are inconsistent with calculations solely using the elastic nucleon intermediate state, and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A_n provides a direct probe of the imaginary component of the two-photon exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.

  13. Slip-stacking Dynamics for High-Power Proton Beams at Fermilab

    SciTech Connect

    Eldred, Jeffrey Scott

    2015-12-01

    Slip-stacking is a particle accelerator configuration used to store two particle beams with different momenta in the same ring. The two beams are longitudinally focused by two radiofrequency (RF) cavities with a small frequency difference between them. Each beam is synchronized to one RF cavity and perturbed by the other RF cavity. Fermilab uses slip-stacking in the Recycler so as to double the power of the 120 GeV proton beam in the Main Injector. This dissertation investigates the dynamics of slip-stacking beams analytically, numerically and experimentally. In the analytic analysis, I find the general trajectory of stable slip-stacking particles and identify the slip-stacking parametric resonances. In the numerical analysis, I characterize the stable phase-space area and model the particle losses. In particular, I evaluate the impact of upgrading the Fermilab Booster cycle-rate from 15 Hz to 20 Hz as part of the Proton Improvement Plan II (PIP-II). The experimental analysis is used to verify my approach to simulating slip-stacking loss. I design a study for measuring losses from the longitudinal single-particle dynamics of slip-stacking as a function of RF cavity voltage and RF frequency separation. I further propose the installation of a harmonic RF cavity and study the dynamics of this novel slip-stacking configuration. I show the harmonic RF cavity cancels out parametric resonances in slip-stacking, reduces emittance growth during slip-stacking, and dramatically enhances the stable phase-space area. The harmonic cavity is expected to reduce slip-stacking losses to far exceed PIP-II requirements. These results raise the possibility of extending slip-stacking beyond the PIP-II era.

  14. Slip-stacking dynamics for high-power proton beams at Fermilab

    NASA Astrophysics Data System (ADS)

    Eldred, Jeffrey

    Slip-stacking is a particle accelerator configuration used to store two particle beams with different momenta in the same ring. The two beams are longitudinally focused by two radiofrequency (RF) cavities with a small frequency difference between them. Each beam is synchronized to one RF cavity and perturbed by the other RF cavity. Fermilab uses slip-stacking in the Recycler as to double the power of the 120 GeV proton beam in the Main Injector. This dissertation investigates the dynamics of slip-stacking beams analytically, numerically and experimentally. In the analytic analysis, I find the general trajectory of stable slip-stacking particles and identify the slip-stacking parametric resonances. In the numerical analysis, I characterize the stable phase-space area and model the particle losses. In particular, I evaluate the impact of upgrading the Fermilab Booster cycle-rate from 15 Hz to 20 Hz as part of the Proton Improvement Plan II (PIP-II). The experimental analysis is used to verify my approach to simulating slip-stacking loss. I design a study for measuring losses from the longitudinal single-particle dynamics of slip-stacking as a function of RF cavity voltage and RF frequency separation. I further propose the installation of a harmonic RF cavity and study the dynamics of this novel slip-stacking configuration. I show the harmonic RF cavity cancels out parametric resonances in slip-stacking, reduces emittance growth during slip-stacking, and dramatically enhances the stable phase-space area. The harmonic cavity is expected to reduce slip-stacking losses to far exceed PIP-II requirements. These results raise the possibility of extending slip-stacking beyond the PIP-II era.

  15. A beam optics study of the biomedical beam line at a proton therapy facility

    NASA Astrophysics Data System (ADS)

    Yun, Chong Cheoul; Kim, Jong-Won

    2007-10-01

    A biomedical beam line has been designed for the experimental area of a proton therapy facility to deliver mm to sub-mm size beams in the energy range of 20-50 MeV using the TRANSPORT/TURTLE beam optics codes and a newly-written program. The proton therapy facility is equipped with a 230 MeV fixed-energy cyclotron and an energy selection system based on a degrader and slits, so that beam currents available for therapy decrease at lower energies in the therapeutic beam energy range of 70-230 MeV. The new beam line system is composed of an energy-degrader, two slits, and three quadrupole magnets. The minimum beam sizes achievable at the focal point are estimated for the two energies of 50 and 20 MeV. The focused FWHM beam size is approximately 0.3 mm with an expected beam current of 20 pA when the beam energy is reduced to 50 MeV from 100 MeV, and roughly 0.8 mm with a current of 10 pA for a 20 MeV beam.

  16. Comments on Injector Proton Beam Study in Run 2014

    SciTech Connect

    Zhang, S. Y.

    2014-09-15

    During the entire period of injector proton study in run 2014, it seems that the beam transverse emittance out of Booster is larger than that in run 2013. The emittance measured at the BtA transfer line and also the transmission from Booster late to AGS late are presented for this argument. In addition to this problem, it seems that the multiturn Booster injection, which defines the transverse emittance, needs more attention. Moreover, for high intensity operations, the space charge effect may be already relevant in RHIC polarized proton runs. With the RHIC proton intensity improvement in the next several years, higher Booster input intensity is needed, therefore, the space charge effect at the Booster injection and early ramp may become a new limiting factor.

  17. Determination of the beam-spin asymmetry of deuteron photodisintegration in the energy region Eγ=1.1 –2.3 GeV

    SciTech Connect

    Zachariou, N.; Ilieva, Y.; Ivanov, N. Ya.; Sargsian, M. M.; Avakian, R.; Feldman, G.; Nadel-Turonski, P.

    2015-05-01

    The beam-spin asymmetry, Σ, for the reaction γd→ΣΣpn has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab) for six photon-energy bins, between 1.1 and 2.3 GeV, and proton angles in the center-of-mass frame, Θc.m., between 25° and 160°. These are the first measurements of beam-spin asymmetries at Θc.m.=90° for photon-beam energies above 1.6 GeV, and the first measurements for angles other than Θc.m.=90°. The angular and energy dependence of Σ is expected to aid in the development of QCD-based models to understand the mechanisms of deuteron photodisintegration in the transition region between hadronic and partonic degrees of freedom, where both effective field theories and perturbative QCD cannot make reliable predictions.

  18. Determination of the beam-spin asymmetry of deuteron photodisintegration in the energy region Eγ=1.1 –2.3 GeV

    DOE PAGESBeta

    Zachariou, N.; Ilieva, Y.; Ivanov, N. Ya.; Sargsian, M. M.; Avakian, R.; Feldman, G.; Nadel-Turonski, P.

    2015-05-01

    The beam-spin asymmetry, Σ, for the reaction γd→ΣΣpn has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab) for six photon-energy bins, between 1.1 and 2.3 GeV, and proton angles in the center-of-mass frame, Θc.m., between 25° and 160°. These are the first measurements of beam-spin asymmetries at Θc.m.=90° for photon-beam energies above 1.6 GeV, and the first measurements for angles other than Θc.m.=90°. The angular and energy dependence of Σ is expected to aid in the development of QCD-based models to understand the mechanisms of deuteron photodisintegration in the transition regionmore » between hadronic and partonic degrees of freedom, where both effective field theories and perturbative QCD cannot make reliable predictions.« less

  19. Analysis ob beam losses at PSR (Proton Storage Ring)

    SciTech Connect

    Macek, R.J.; Fitzgerald, D.H.; Hutson, R.L.; Plum, M.A.; Thiessen, H.A.

    1988-01-01

    Beam losses and the resulting component activation at the Los Alamos Proton Storage Ring (PSR) have limited operating currents to about 30..mu..A average at a repetition rate of 15 Hz. Loss rates were found to be approximately proportional to the circulating current and can be understood by a detailed accounting of emittance growth in the two step injection process along with Coulomb scattering of the stored beam during multiple traversals of the injection foil. Calculations and simulations of the losses are in reasonable agreement with measurements.

  20. Proton beam therapy for locally advanced lung cancer: A review

    PubMed Central

    Schild, Steven E; Rule, William G; Ashman, Jonathan B; Vora, Sujay A; Keole, Sameer; Anand, Aman; Liu, Wei; Bues, Martin

    2014-01-01

    Protons interact with human tissue differently than do photons and these differences can be exploited in an attempt to improve the care of lung cancer patients. This review examines proton beam therapy (PBT) as a component of a combined modality program for locally advanced lung cancers. It was specifically written for the non-radiation oncologist who desires greater understanding of this newer treatment modality. This review describes and compares photon (X-ray) radiotherapy (XRT) to PBT. The physical differences of these beams are described and the clinical literature is reviewed. Protons can be used to create treatment plans delivering significantly lower doses of radiation to the adjacent organs at risk (lungs, esophagus, and bone marrow) than photons. Clinically, PBT combined with chemotherapy has resulted in low rates of toxicity compared to XRT. Early results suggest a possible improvement in survival. The clinical results of proton therapy in lung cancer patients reveal relatively low rates of toxicity and possible survival benefits. One randomized study is being performed and another is planned to clarify the clinical differences in patient outcome for PBT compared to XRT. Along with the development of better systemic therapy, newer forms of radiotherapy such as PBT should positively impact the care of lung cancer patients. This review provides the reader with the current status of this new technology in treating locally advanced lung cancer. PMID:25302161

  1. Proteomic Analysis of Proton Beam Irradiated Human Melanoma Cells

    PubMed Central

    Kedracka-Krok, Sylwia; Jankowska, Urszula; Elas, Martyna; Sowa, Urszula; Swakon, Jan; Cierniak, Agnieszka; Olko, Pawel; Romanowska-Dixon, Bozena; Urbanska, Krystyna

    2014-01-01

    Proton beam irradiation is a form of advanced radiotherapy providing superior distributions of a low LET radiation dose relative to that of photon therapy for the treatment of cancer. Even though this clinical treatment has been developing for several decades, the proton radiobiology critical to the optimization of proton radiotherapy is far from being understood. Proteomic changes were analyzed in human melanoma cells treated with a sublethal dose (3 Gy) of proton beam irradiation. The results were compared with untreated cells. Two-dimensional electrophoresis was performed with mass spectrometry to identify the proteins. At the dose of 3 Gy a minimal slowdown in proliferation rate was seen, as well as some DNA damage. After allowing time for damage repair, the proteomic analysis was performed. In total 17 protein levels were found to significantly (more than 1.5 times) change: 4 downregulated and 13 upregulated. Functionally, they represent four categories: (i) DNA repair and RNA regulation (VCP, MVP, STRAP, FAB-2, Lamine A/C, GAPDH), (ii) cell survival and stress response (STRAP, MCM7, Annexin 7, MVP, Caprin-1, PDCD6, VCP, HSP70), (iii) cell metabolism (TIM, GAPDH, VCP), and (iv) cytoskeleton and motility (Moesin, Actinin 4, FAB-2, Vimentin, Annexin 7, Lamine A/C, Lamine B). A substantial decrease (2.3 x) was seen in the level of vimentin, a marker of epithelial to mesenchymal transition and the metastatic properties of melanoma. PMID:24392146

  2. Cost-Effectiveness of Proton Beam Therapy for Intraocular Melanoma

    PubMed Central

    Moriarty, James P.; Borah, Bijan J.; Foote, Robert L.; Pulido, Jose S.; Shah, Nilay D.

    2015-01-01

    Purpose Proton beam therapy is a commonly accepted treatment for intraocular melanomas, but the literature is lacking in descriptions of patient preferences of clinical outcomes and economic impact. In addition, no economic evaluations have been published regarding the incremental cost-effectiveness of proton beam therapy compared with enucleation or plaque brachytherapy, typical alternative treatments. We, therefore, conducted a cost-utility analysis of these three approaches for the treatment of intraocular melanomas. Materials and Methods A Markov model was constructed. Model parameters were identified from the published literature and publicly available data sources. Cost-effectiveness of each treatment was calculated in 2011 US Dollars per quality-adjusted life-year. Incremental cost-effectiveness ratios were calculated assuming enucleation as reference. One-way sensitivity analyses were conducted on all model parameters. A decision threshold of $50,000/quality-adjusted life-year was used to determine cost-effectiveness. Results Enucleation had the lowest costs and quality-adjusted life-years, and plaque brachytherapy had the highest costs and quality-adjusted life-years. Compared with enucleation, the base-case incremental cost-effectiveness ratios for plaque brachytherapy and proton beam therapy were $77,500/quality-adjusted life-year and $106,100/quality-adjusted life-year, respectively. Results were highly sensitive to multiple parameters. All three treatments were considered optimal, and even dominant, depending on the values used for sensitive parameters. Conclusion Base-case analysis results suggest enucleation to be optimal. However, the optimal choice was not robust to sensitivity analyses and, depending on the assumption, both plaque brachytherapy and proton beam therapy could be considered cost-effective. Future clinical studies should focus on generating further evidence with the greatest parameter uncertainty to inform future cost

  3. Proton beam scattering system optimization for clinical and research applications

    SciTech Connect

    Wroe, A. J.; Schulte, R. W.; Slater, J. D.; Barnes, S.; McAuley, G.; Slater, J. M.

    2013-04-15

    Purpose: To develop and test a method for optimizing and constructing a dual scattering system in passively scattered proton therapy. Methods: A beam optics optimization algorithm was developed to optimize the thickness of the first scatterer (S1) and the profile (of both the high-Z material and Lexan) of the second scatterer (S2) to deliver a proton beam matching a given set of parameters, including field diameter, fluence, flatness, and symmetry. A new manufacturing process was also tested that allows the contoured second scattering foil to be created much more economically and quickly using Cerrobend casting. Two application-specific scattering systems were developed and tested using both experimental and Monte Carlo techniques to validate the optimization process described. Results: A scattering system was optimized and constructed to deliver large uniform irradiations of radiobiology samples at low dose rates. This system was successfully built and tested using film and ionization chambers. The system delivered a uniform radiation field of 50 cm diameter (to a dose of {+-}7% of the central axis) while the depth dose profile could be tuned to match the specifications of the particular investigator using modulator wheels and range shifters. A second scattering system for intermediate field size (4 cm < diameter < 10 cm) stereotactic radiosurgery and radiation therapy (SRS and SRT) treatments was also developed and tested using GEANT4. This system improved beam efficiency by over 70% compared with existing scattering systems while maintaining field flatness and depth dose profile. In both cases the proton range uniformity across the radiation field was maintained, further indicating the accuracy of the energy loss formalism in the optimization algorithm. Conclusions: The methods described allow for rapid prototyping of scattering foils to meet the demands of both research and clinical beam delivery applications in proton therapy.

  4. Proton Beam Therapy for Aged Patients With Hepatocellular Carcinoma

    SciTech Connect

    Hata, Masaharu Tokuuye, Koichi; Sugahara, Shinji; Tohno, Eriko; Nakayama, Hidetsugu; Fukumitsu, Nobuyoshi; Mizumoto, Masashi; Abei, Masato; Shoda, Junichi; Minami, Manabu; Akine, Yasuyuki

    2007-11-01

    Purpose: To investigate the safety and efficacy of proton beam therapy for aged patients with hepatocellular carcinoma (HCC). Methods and Materials: Twenty-one patients aged {>=}80 years with HCC underwent proton beam therapy. At the time of irradiation, patient age ranged from 80 to 85 years (median, 81 years). Hepatic tumors were solitary in 17 patients and multiple in 4. Tumor size ranged from 10 to 135 mm (median, 40 mm) in maximum diameter. Ten, 5, and 6 patients received proton beam irradiation with total doses of 60 Gy in 10 fractions, 66 Gy in 22 fractions, and 70 Gy in 35 fractions, respectively, according to tumor location. Results: All irradiated tumors were controlled during the follow-up period of 6-49 months (median, 16 months). Five patients showed new hepatic tumors outside the irradiated volume, 2-13 months after treatment, and 1 of them also had lung metastasis. The local progression-free and disease-free rates were 100% and 72% at 3 years, respectively. Of 21 patients, 7 died 6-49 months after treatment; 2 patients each died of trauma and old age, and 1 patient each died of HCC, pneumonia, and arrhythmia. The 3-year overall, cause-specific, and disease-free survival rates were 62%, 88%, and 51%, respectively. No therapy-related toxicity of Grade {>=} 3 but thrombocytopenia in 2 patients was observed. Conclusions: Proton beam therapy seems to be tolerable, effective, and safe for aged patients with HCC. It may contribute to prolonged survival due to tumor control.

  5. Capacitive beam position monitors for the low-β beam of the Chinese ADS proton linac

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Wu, Jun-Xia; Zhu, Guang-Yu; Jia, Huan; Xue, Zong-Heng; Zheng, Hai; Xie, Hong-Ming; Kang, Xin-Cai; He, Yuan; Li, Lin; Denard, Jean Claude

    2016-02-01

    Beam Position Monitors (BPMs) for the low-β beam of the Chinese Accelerator Driven Subcritical system (CADS) Proton linac are of the capacitive pick-up type. They provide higher output signals than that of the inductive type. This paper will describe the design and tests of the capacitive BPM system for the low-β proton linac, including the pick-ups, the test bench and the read-out electronics. The tests done with an actual proton beam show a good agreement between the measurements and the simulations in the time domain. Supported by National Natural Science Foundation of China (11405240) and “Western Light” Talents Training Program of Chinese Academy of Sciences

  6. Scaling properties of proton and antiproton production in sqrt[s(NN)]=200 GeV Au+Au collisions.

    PubMed

    Adler, S S; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Alexander, J; Amirikas, R; Aphecetche, L; Aronson, S H; Averbeck, R; Awes, T C; Azmoun, R; Babintsev, V; Baldisseri, A; Barish, K N; Barnes, P D; Bassalleck, B; Bathe, S; Batsouli, S; Baublis, V; Bazilevsky, A; Belikov, S; Berdnikov, Y; Bhagavatula, S; Boissevain, J G; Borel, H; Borenstein, S; Brooks, M L; Brown, D S; Bruner, N; Bucher, D; Buesching, H; Bumazhnov, V; Bunce, G; Burward-Hoy, J M; Butsyk, S; Camard, X; Chai, J-S; Chand, P; Chang, W C; Chernichenko, S; Chi, C Y; Chiba, J; Chiu, M; Choi, I J; Choi, J; Choudhury, R K; Chujo, T; Cianciolo, V; Cobigo, Y; Cole, B A; Constantin, P; d'Enterria, D G; David, G; Delagrange, H; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Drapier, O; Drees, A; du Rietz, R; Durum, A; Dutta, D; Efremenko, Y V; El Chenawi, K; Enokizono, A; En'yo, H; Esumi, S; Ewell, L; Fields, D E; Fleuret, F; Fokin, S L; Fox, B D; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fung, S-Y; Garpman, S; Ghosh, T K; Glenn, A; Gogiberidze, G; Gonin, M; Gosset, J; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grosse Perdekamp, G; Guryn, W; Gustafsson, H-A; Hachiya, T; Haggerty, J S; Hamagaki, H; Hansen, A G; Hartouni, E P; Harvey, M; Hayano, R; He, X; Heffner, M; Hemmick, T K; Heuser, J M; Hibino, M; Hill, J C; Holzmann, W; Homma, K; Hong, B; Hoover, A; Ichihara, T; Ikonnikov, V V; Imai, K; Isenhower, L D; Ishihara, M; Issah, M; Isupov, A; Jacak, B V; Jang, W Y; Jeong, Y; Jia, J; Jinnouchi, O; Johnson, B M; Johnson, S C; Joo, K S; Jouan, D; Kametani, S; Kamihara, N; Kang, J H; Kapoor, S S; Katou, K; Kelly, S; Khachaturov, B; Khanzadeev, A; Kikuchi, J; Kim, D H; Kim, D J; Kim, D W; Kim, E; Kim, G-B; Kim, H J; Kistenev, E; Kiyomichi, A; Kiyoyama, K; Klein-Boesing, C; Kobayashi, H; Kochenda, L; Kochetkov, V; Koehler, D; Kohama, T; Kopytine, M; Kotchetkov, D; Kozlov, A; Kroon, P J; Kuberg, C H; Kurita, K; Kuroki, Y; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Ladygin, V; Lajoie, J G; Lebedev, A; Leckey, S; Lee, D M; Lee, S; Leitch, M J; Li, X H; Lim, H; Litvinenko, A; Liu, M X; Liu, Y; Maguire, C F; Makdisi, Y I; Malakhov, A; Manko, V I; Mao, Y; Martinez, G; Marx, M D; Masui, H; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E; Messer, F; Miake, Y; Milan, J; Miller, T E; Milov, A; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Mühlbacher, F; Mukhopadhyay, D; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagle, J L; Nakamura, T; Nandi, B K; Nara, M; Newby, J; Nilsson, P; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Okada, K; Ono, M; Onuchin, V; Oskarsson, A; Otterlund, I; Oyama, K; Ozawa, K; Pal, D; Palounek, A P T; Pantuev, V S; Papavassiliou, V; Park, J; Parmar, A; Pate, S F; Peitzmann, T; Peng, J-C; Peresedov, V; Pinkenburg, C; Pisani, R P; Plasil, F; Purschke, M L; Purwar, A; Rak, J; Ravinovich, I; Read, K F; Reuter, M; Reygers, K; Riabov, V; Riabov, Y; Roche, G; Romana, A; Rosati, M; Rosnet, P; Ryu, S S; Sadler, M E; Saito, N; Sakaguchi, T; Sakai, M; Sakai, S; Samsonov, V; Sanfratello, L; Santo, R; Sato, H D; Sato, S; Sawada, S; Schutz, Y; Semenov, V; Seto, R; Shaw, M R; Shea, T K; Shibata, T-A; Shigaki, K; Shiina, T; Silva, C L; Silvermyr, D; Sim, K S; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Staley, F; Stankus, P W; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Sugitate, T; Sullivan, J P; Takagui, E M; Taketani, A; Tamai, M; Tanaka, K H; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarján, P; Tepe, J D; Thomas, T L; Tojo, J; Torii, H; Towell, R S; Tserruya, I; Tsuruoka, H; Tuli, S K; Tydesjö, H; Tyurin, N; Van Hecke, H W; Velkovska, J; Velkovsky, M; Villatte, L; Vinogradov, A A; Volkov, M A; Vznuzdaev, E; Wang, X R; Watanabe, Y; White, S N; Wohn, F K; Woody, C L; Xie, W; Yang, Y; Yanovich, A; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L

    2003-10-24

    We report on the yield of protons and antiprotons, as a function of centrality and transverse momentum, in Au+Au collisions at sqrt[s(NN)]=200 GeV measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. In central collisions at intermediate transverse momenta (1.5protons and antiprotons. They show a centrality-scaling behavior different from that of pions. The pmacr;/pi and p/pi ratios are enhanced compared to peripheral Au+Au, p+p, and e(+)e(-) collisions. This enhancement is limited to p(T)<5 GeV/c as deduced from the ratio of charged hadrons to pi(0) measured in the range 1.5

  7. Radiobiological study by using laser-driven proton beams

    SciTech Connect

    Yogo, A.; Nishikino, M.; Mori, M.; Ogura, K.; Sagisaka, A.; Orimo, S.; Nishiuchi, M.; Pirozhkov, A. S.; Ikegami, M.; Tampo, M.; Sakaki, H.; Suzuki, M.; Daito, I.; Kiriyama, H.; Okada, H.; Kanazawa, S.; Kondo, S.; Shimomura, T.; Nakai, Y.; Kawachi, T.

    2009-07-25

    Particle acceleration driven by high-intensity laser systems is widely attracting interest as a potential alternative to conventional ion acceleration, including ion accelerator applications to tumor therapy. Recent works have shown that a high intensity laser pulse can produce single proton bunches of a high current and a short pulse duration. This unique feature of laser-ion acceleration can lead to progress in the development of novel ion sources. However, there has been no experimental study of the biological effects of laser-driven ion beams. We describe in this report the first demonstrated irradiation effect of laser-accelerated protons on human lung cancer cells. In-vitro A549 cells are irradiated with a proton dose of 20 Gy, resulting in a distinct formation of gamma-H2AX foci as an indicator of DNA double-strand breaks. This is a pioneering result that points to future investigations of the radiobiological effects of laser-driven ion beams. The laser-driven ion beam is apotential excitation source for time-resolved determination of hydroxyl (OH) radical yield, which will explore relationship between the fundamental chemical reactions of radiation effects and consequent biological processes.

  8. Radiobiological study by using laser-driven proton beams

    NASA Astrophysics Data System (ADS)

    Yogo, A.; Sato, K.; Nishikino, M.; Mori, M.; Teshima, T.; Numasaki, H.; Murakami, M.; Demizu, Y.; Akagi, S.; Nagayama, S.; Ogura, K.; Sagisaka, A.; Orimo, S.; Nishiuchi, M.; Pirozhkov, A. S.; Ikegami, M.; Tampo, M.; Sakaki, H.; Suzuki, M.; Daito, I.; Oishi, Y.; Sugiyama, H.; Kiriyama, H.; Okada, H.; Kanazawa, S.; Kondo, S.; Shimomura, T.; Nakai, Y.; Tanoue, M.; Sugiyama, H.; Sasao, H.; Wakai, D.; Kawachi, T.; Nishimura, H.; Bolton, P. R.; Daido, H.

    2009-07-01

    Particle acceleration driven by high-intensity laser systems is widely attracting interest as a potential alternative to conventional ion acceleration, including ion accelerator applications to tumor therapy. Recent works have shown that a high intensity laser pulse can produce single proton bunches of a high current and a short pulse duration. This unique feature of laser-ion acceleration can lead to progress in the development of novel ion sources. However, there has been no experimental study of the biological effects of laser-driven ion beams. We describe in this report the first demonstrated irradiation effect of laser-accelerated protons on human lung cancer cells. In-vitro A549 cells are irradiated with a proton dose of 20 Gy, resulting in a distinct formation of γ-H2AX foci as an indicator of DNA double-strand breaks. This is a pioneering result that points to future investigations of the radiobiological effects of laser-driven ion beams. The laser-driven ion beam is apotential excitation source for time-resolved determination of hydroxyl (OH) radical yield, which will explore relationship between the fundamental chemical reactions of radiation effects and consequent biological processes.

  9. Proton beam writing of submicrometer structures at LIPSION

    NASA Astrophysics Data System (ADS)

    Menzel, F.; Spemann, D.; Petriconi, S.; Lenzner, J.; Butz, T.

    2007-07-01

    We report on the current status of proton beam writing (PBW) at LIPSION. At present, minimal feature sizes of 130 nm were obtained in SU-8. For this purpose 10 μm thick SU-8 was irradiated with 2.25 MeV protons under STIM conditions (˜1 fA) using a dedicated scan program. These structures have an aspect ratio of 77. However, artefacts from beam spot fluctuations and instabilities due to their large height are noticeable. Furthermore, Ni grids of different sizes and pitches were produced by electroplating. The corresponding templates were written in a negative resist called ma-N 440, which can be removed much more easily compared to SU-8 after the plating step and therefore offers the advantage of a large area Ni grow and a better control of the plating current density. This results in a higher quality concerning the homogeneity of the Ni-layer. In addition, an experimental setup for the electrochemical etching of silicon was constructed and Si structures were created by proton beam writing of Si, reaching minimal lateral dimensions of 1.2 μm.

  10. Production of high-brightness CW proton beams with very high proton fractions

    SciTech Connect

    Spence, D.; McMichael, G.; Lykke, K.R.; Schneider, J.D.; Sherman, J.; Stevens, R. Jr.; Hodgkins, D.

    1995-12-01

    This paper demonstrates a new technique to significantly enhance the proton fraction of an ion beam extracted from a plasma ion source. We employ a magnetically confined microwave driven source, though the technique is not source-specific and can probably be applied equally effectively to other plasma sources such as Penning and multicusp types. Specifically, we dope the plasma with about 1% H{sub 2}O, which increases the proton fraction of a 45 keV 45 mA beam from 75 to 90% with 375W 2.45 GHz power to the source and from 84% to 92% for 500W when the source is operated under nonresonant conditions. Much of the remaining fraction of the beam comprises a heavy mass ion we believe to be N{sup +} impurity ions resulting from the conditions under which the experiments were performed. If so, this impurity can be easily removed and much higher proton fractions could be expected. Preliminary measurements show the additive has no adverse effect on the emittance of the extracted beam, and source stability is greatly improved.