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Sample records for antiproton radiotherapy measurements

  1. Antiproton radiotherapy

    CERN Document Server

    Bassler, Niels; Beyer, Gerd; DeMarco, John J.; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Iwamoto, Keisuke S.; Jakel, Oliver; Knudsen, Helge V.; Kovacevic, Sandra; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen B.à; Solberg, Timothy D.; Sørensen, Brita S.; Vranjes, Sanja; Wouters, Bradly G.; Holzscheiter, Michael H.

    2008-01-01

    Antiprotons are interesting as a possible future modality in radiation therapy for the following reasons: When fast antiprotons penetrate matter, protons and antiprotons have near identical stopping powers and exhibit equal radiobiology well before the Bragg-peak. But when the antiprotons come to rest at the Bragg-peak, they annihilate, releasing almost 2 GeV per antiproton–proton annihilation. Most of this energy is carried away by energetic pions, but the Bragg-peak of the antiprotons is still locally augmented with ∼20–30 MeV per antiproton. Apart from the gain in physical dose, an increased relative biological effect also has been observed, which can be explained by the fact that some of the secondary particles from the antiproton annihilation exhibit high-LET properties. Finally, the weakly interacting energetic pions, which are leaving the target volume, may provide a real time feedback on the exact location of the annihilation peak. We have performed dosimetry experiments and investigated the rad...

  2. Neutron fluence in antiproton radiotherapy, measurements and simulations

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael H.; Petersen, Jørgen B.B.

    2010-01-01

    A significant part of the secondary particle spectrum from antiproton annihilation consists of fast neutrons, which may contribute to a significant dose background found outside the primary beam. Using a polystyrene phantom as a moderator, we have performed absolute measurements of the thermalized...... part of the fast neutron spectrum using Lithium-6 and -7 Fluoride TLD pairs. The experimental results are found to be in good agreement with simulations using the Monte Carlo particle transport code FLUKA. The thermal neutron kerma resulting from the measured thermal neutron fluence is insignificant...... compared to the contribution from fast neutrons. The results are found to be similar to values calculated for pion treatment, however exact modeling under more realistic treatment scenarios is still required to quantitatively compare these treatment modalities....

  3. Measurement of interaction between antiprotons

    Science.gov (United States)

    The Star Collaboration; Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Bairathi, V.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandenburg, J. D.; Brandin, A. V.; Bunzarov, I.; Butterworth, J.; Caines, H.; Calderón de La Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Contin, G.; Crawford, H. J.; Das, S.; de Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Z.; Filip, P.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Haque, R.; Harris, J. W.; He, L.; Heppelmann, S.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Jiang, K.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikoła, D. P.; Kisel, I.; Kisiel, A.; Klein, S.; Kochenda, L.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, X.; Li, Z. M.; Li, Y.; Li, W.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R.; Ma, Y. G.; Ma, L.; Magdy, N.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Meehan, K.; Minaev, N. G.; Mioduszewski, S.; Mishra, D.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D.; Page, B. S.; Pak, R.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlik, B.; Pei, H.; Perkins, C.; Peterson, A.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, M. K.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stepanov, M.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B.; Sun, Z.; Sun, X. M.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, N.; Szelezniak, M. A.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Y.; Wang, Y.; Wang, F.; Webb, J. C.; Webb, G.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z. G.; Xie, W.; Xin, K.; Xu, Y. F.; Xu, Q. H.; Xu, H.; Xu, N.; Xu, Z.; Yang, Y.; Yang, C.; Yang, S.; Yang, Y.; Yang, Q.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, Z.; Zhang, J.; Zhang, S.; Zhang, X. P.; Zhang, J.; Zhang, Y.; Zhao, J.; Zhong, C.; Zhou, L.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.

    2015-11-01

    One of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force that has since been acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, little is known directly about the nuclear force between antinucleons. Here, we study antiproton pair correlations among data collected by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC), where gold ions are collided with a centre-of-mass energy of 200 gigaelectronvolts per nucleon pair. Antiprotons are abundantly produced in such collisions, thus making it feasible to study details of the antiproton-antiproton interaction. By applying a technique similar to Hanbury Brown and Twiss intensity interferometry, we show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: the scattering length and the effective range of the interaction. Our measured parameters are consistent within errors with the corresponding values for proton-proton interactions. Our results provide direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, and so are fundamental to understanding the structure of more-complex antinuclei and their properties.

  4. Antiproton radiotherapy: peripheral dose from secondary neutrons

    DEFF Research Database (Denmark)

    Fahimian, Benjamin P.; DeMarco, John J.; Keyes, Roy

    2009-01-01

    is the normal tissue dose resulting from secondary neutrons produced in the annihilation of antiprotons on the nucleons of the target atoms. Here we present the first organ specific Monte Carlo calculations of normal tissue equivalent neutron dose in antiproton therapy through the use of a segmented CT......-based human phantom. The MCNPX Monte Carlo code was employed to quantify the peripheral dose for a cylindrical spread out Bragg peak representing a treatment volume of 1 cm diameter and 1 cm length in the frontal lobe of a segmented whole-body phantom of a 38 year old male. The secondary neutron organ dose...

  5. Measurement of interaction between antiprotons

    Czech Academy of Sciences Publication Activity Database

    Adamczyk, L.; Bielčík, J.; Bielčíková, Jana; Federič, Pavol; Chaloupka, P.; Rusňák, Jan; Rusňáková, O.; Šimko, Miroslav; Šumbera, Michal; Tlustý, David; Trzeciak, B. A.; Vértési, Robert

    2015-01-01

    Roč. 527, č. 7578 (2015), s. 345-348 ISSN 0028-0836 R&D Projects: GA ČR GA13-20841S Institutional support: RVO:61389005 Keywords : STAR collaboration * antiprotons * protons Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 38.138, year: 2015

  6. Antiproton Radiotherapy Peripheral Dose from Secondary Neutrons produced in the Annihilation of Antiprotons in the Target

    CERN Document Server

    Fahimian, Benjamin P; Keyes, Roy; Bassler, Niels; Iwamoto, Keisuke S; Zankl, Maria; Holzscheiter, Michael H

    2009-01-01

    The AD-4/ACE collaboration studies the biological effects of antiprotons with respect to a possible use of antiprotons in cancer therapy. In vitro experiments performed by the collaboration have shown an enhanced biological effectiveness for antiprotons relative to protons. One concern is the normal tissue dose resulting from secondary neutrons produced in the annihilation of antiprotons on the nucleons of the target atoms. Here we present the first organ specific Monte Carlo calculations of normal tissue equivalent neutron dose in antiproton therapy through the use of a segmented CT-based human phantom. The MCNPX Monte Carlo code was employed to quantify the peripheral dose for a cylindrical spread out Bragg peak representing a treatment volume of 1 cm diameter and 1 cm length in the frontal lobe of a segmented whole-body phantom of a 38 year old male. The secondary neutron organ dose was tallied as a function of energy and organ.

  7. Measurement of strong interaction parameters in antiprotonic hydrogen and deuterium

    CERN Document Server

    Augsburger, M A; Borchert, G L; Chatellard, D; Egger, J P; El-Khoury, P; Gorke, H; Gotta, D; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Siems, T; Simons, L M

    1999-01-01

    In the PS207 experiment at CERN, X-rays from antiprotonic hydrogen and deuterium have been measured at low pressure. The strong interaction shift and the broadening of the K/sub alpha / transition in antiprotonic hydrogen were $9 determined. Evidence was found for the individual hyperfine components of the protonium ground state. (7 refs).

  8. Simulation of an antiprotons beam applied to the radiotherapy

    International Nuclear Information System (INIS)

    Prata, Leonardo de Almeida

    2006-07-01

    Results for the interaction of a antiproton beam with constituent nuclei of the organic matter are presented. This method regards of the application of an computational algorithm to determine quantitatively the differential cross sections for the scattered particles, starting from the interaction of these antiprotons with the nuclei, what will allow in the future to draw the isodose curve for antiproton therapy, once these beams are expected to be used in cancer treatment soon. The calculation will be done through the application of the concepts of the method of intranuclear cascade, providing yield and differential cross sections of the scattered particles, present in the software MCMC. Th algorithm was developed based on Monte Carlo's method, already taking into account a validate code. The following physical quantities are presented: the yield of secondary particles, their spectral and angular distributions for these interactions. For the energy range taken into account the more important emitted particles are protons, neutrons and pions. Results shown that emitted secondary particles can modify the isodose curves, because they present high yield and energy for transverse directions. (author)

  9. Energy and energy width measurement in the FNAL antiproton accumulator

    International Nuclear Information System (INIS)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H 2 gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10 4 in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter η = (P beam /F rev )·(dF rev /dP beam ). These two measurement techniques are described in this report

  10. Energy and energy width measurement in the FNAL antiproton accumulator

    Energy Technology Data Exchange (ETDEWEB)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H{sub 2} gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10{sup 4} in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter {eta} = (P{sub beam}/F{sub rev}){center_dot}(dF{sub rev}/dP{sub beam}). These two measurement techniques are described in this report.

  11. Measurement of antiproton production in $p$–He collisions at LHCb to constrain the secondary cosmic antiproton flux

    CERN Document Server

    Graziani, Giacomo

    2018-01-01

    The flux of cosmic ray antiprotons is a powerful tool for indirect detection of dark matter. The sensitivity is limited by the uncertainty on the predicted antiproton flux from scattering of primary rays on the interstellar medium. This is, in turn, limited by the knowledge of production cross-sections, notably in p–He scattering. Thanks to its internal gas target, the LHCb experiment performed the first measurement of antiproton production from collisions of LHC proton beams on He nuclei at rest. The results and prospects are presented.

  12. Hyperfine Structure Measurements of Antiprotonic $^3$He using Microwave Spectroscopy

    CERN Document Server

    Friedreich, Susanne

    The goal of this project was to measure the hyperfine structure of $\\overline{\\text{p}}^3$He$^+$ using the technique of laser-microwave-laser spectroscopy. Antiprotonic helium ($\\overline{\\text{p}}$He$^+$) is a neutral exotic atom, consisting of a helium nucleus, an electron and an antiproton. The interactions of the angular momenta of its constituents cause a hyperfine splitting ({HFS}) within the energy states of this new atom. The 3\\% of formed antiprotonic helium atoms which remain in a metastable, radiative decay-dominated state have a lifetime of about 1-3~$\\mu$s. This time window is used to do spectroscopic studies. The hyperfine structure of $\\overline{\\text{p}}^4$He$^+$ was already extensively investigated before. From these measurements the spin magnetic moment of the antiproton can be determined. A comparison of the result to the proton magnetic moment provides a test of {CPT} invariance. Due to its higher complexity the new exotic three-body system of $\\overline{\\text{p}}^3$He$^+$ is a cross-check...

  13. Beam Diagnostics for Measurements of Antiproton Annihilation Cross Sections at Ultra-low Energy

    Directory of Open Access Journals (Sweden)

    Todoroki K.

    2014-03-01

    Full Text Available The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons collaboration of CERN is currently attempting to measure the antiproton-nucleus in-flight annihilation cross sections on thin target foils of C, Pd, and Pt at 130 keV of kinetic energy. The low-energy antiprotons were supplied by the Antiproton Decelerator (AD and a radio-frequency quadrupole decelerator. For this measurement, a beam profile monitor based on secondary electron emission was developed. Data from this monitor was used to ensure that antiprotons were precisely tuned to the position of an 80-mm-diameter experimental target, by measuring the spatial profile of 200-ns-long beam pulses containing 105 − 106 antiprotons with an active area of 40 mm × 40 mm and a spatial resolution of 4 mm. By using this monitor, we succeeded in finely tuning antiproton beams on the target, and observed some annihilation events originating from the target.

  14. Antiproton therapy

    CERN Document Server

    Knudsen, Helge V; Bassler, Niels; Alsner, Jan; Beyer, Gerd-Jürgen; DeMarco, John J; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Iwamoto, Keisuke S; Jäkel, Oliver; Kovacevic, Sandra; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen B; Ratib, Osman; Solberg, Timothy D; Vranjes, Sanja; Wouters, Bradly G

    2008-01-01

    Radiotherapy is one of the most important means we have for the treatment of localised tumours. It is therefore essential to optimize the technique, and a lot of effort goes into this endeavour. Since the proposal by Wilson in 1946 [R.R. Wilson, Radiology use of fast protons, Radiology 47 (1946) 487.] that proton beams might be better than photon beams at inactivating cancer cells, hadron therapy has been developed in parallel with photon therapy and a substantial knowledge has been gained on the effects of pions, protons and heavy ions (mostly carbon ions). Here we discuss the recent measurements by the CERN ACE collaboration of the biological effects of antiprotons, and argue that these particles very likely are the optimal agents for radiotherapy.

  15. Antiproton beam profile measurements using Gas Electron Multipliers

    CERN Document Server

    Duarte Pinto, Serge; Spanggaard, Jens; Tranquille, Gerard

    2011-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X_0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEgIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  16. The antiproton depth–dose curve measured with alanine detectors

    CERN Document Server

    Bassler, Niels; Palmans, Hugo; Holzscheiter, Michael H; Kovacevic, Sandra

    2008-01-01

    n this paper we report on the measurement of the antiproton depth–dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen and Olsen for conversion of calculated dose into response. A good agreement is observed between the measured and calculated relative effectiveness although an underestimation of the measured values beyond the Bragg-peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use of the alanine detectors for dosimetry of mixed radiation fields.

  17. The Antiproton Depth Dose Curve Measured with Alanine Detectors

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, Johnny Witterseh; Palmans, Hugo

    2008-01-01

    In this paper we report on the measurement of the antiproton depth dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen et Olsen for conversion of calculated dose...... into response. A good agreement was observed between the measured and calculated relative effectiveness although a slight underestimation of the calculated values in the Bragg peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use...... of the alanine detectors for dosimetry of mixed radiation fields....

  18. Bubble detector measurements of a mixed radiation field from antiproton annihilation

    DEFF Research Database (Denmark)

    Bassler, Niels; Knudsen, Helge; Møller, Søren Pape

    2006-01-01

    In the light of recent progress in the study of the biological potential of antiproton tumour treatment it is important to be able to characterize the neutron intensity arising from antiproton annihilation using simple, compact and reliable detectors. The intensity of fast neutrons from antiproton...... annihilation on polystyrene has been measured with bubble detectors and a multiplicity has been derived as well as an estimated neutron equivalent dose. Additionally the sensitivity of bubble detectors towards protons was measured....

  19. Simulation of an antiprotons beam applied to the radiotherapy; Simulacao de um feixe de antiprotons aplicado a radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Prata, Leonardo de Almeida

    2006-07-15

    Results for the interaction of a antiproton beam with constituent nuclei of the organic matter are presented. This method regards of the application of an computational algorithm to determine quantitatively the differential cross sections for the scattered particles, starting from the interaction of these antiprotons with the nuclei, what will allow in the future to draw the isodose curve for antiproton therapy, once these beams are expected to be used in cancer treatment soon. The calculation will be done through the application of the concepts of the method of intranuclear cascade, providing yield and differential cross sections of the scattered particles, present in the software MCMC. Th algorithm was developed based on Monte Carlo's method, already taking into account a validate code. The following physical quantities are presented: the yield of secondary particles, their spectral and angular distributions for these interactions. For the energy range taken into account the more important emitted particles are protons, neutrons and pions. Results shown that emitted secondary particles can modify the isodose curves, because they present high yield and energy for transverse directions. (author)

  20. Comparison of electromagnetic and hadronic models generated using Geant 4 with antiproton dose measured in CERN.

    Science.gov (United States)

    Tavakoli, Mohammad Bagher; Reiazi, Reza; Mohammadi, Mohammad Mehdi; Jabbari, Keyvan

    2015-01-01

    After proposing the idea of antiproton cancer treatment in 1984 many experiments were launched to investigate different aspects of physical and radiobiological properties of antiproton, which came from its annihilation reactions. One of these experiments has been done at the European Organization for Nuclear Research known as CERN using the antiproton decelerator. The ultimate goal of this experiment was to assess the dosimetric and radiobiological properties of beams of antiprotons in order to estimate the suitability of antiprotons for radiotherapy. One difficulty on this way was the unavailability of antiproton beam in CERN for a long time, so the verification of Monte Carlo codes to simulate antiproton depth dose could be useful. Among available simulation codes, Geant4 provides acceptable flexibility and extensibility, which progressively lead to the development of novel Geant4 applications in research domains, especially modeling the biological effects of ionizing radiation at the sub-cellular scale. In this study, the depth dose corresponding to CERN antiproton beam energy by Geant4 recruiting all the standard physics lists currently available and benchmarked for other use cases were calculated. Overall, none of the standard physics lists was able to draw the antiproton percentage depth dose. Although, with some models our results were promising, the Bragg peak level remained as the point of concern for our study. It is concluded that the Bertini model with high precision neutron tracking (QGSP_BERT_HP) is the best to match the experimental data though it is also the slowest model to simulate events among the physics lists.

  1. Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations

    CERN Document Server

    Sótér, A.; Kobayashi, T.; Barna, D.; Horváth, D.; Hori, M.

    2014-01-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) experiment at the Antiproton Decelerator (AD) facility of CERN constructed segmented scintillators to detect and track the charged pions which emerge from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. A system of 541 cast and extruded scintillator bars were arranged in 11 detector modules which provided a spatial resolution of 17 mm. Green wavelength-shifting fibers were embedded in the scintillators, and read out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The photoelectron yields of various scintillator configurations were measured using a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the AD. Nonlinear effects due to the saturation of the silicon photomultiplier were seen a...

  2. Experimental setup and first measurement of DNA damage induced along and around an antiproton beam

    DEFF Research Database (Denmark)

    Kavanagh, J. N.; Currell, F. J.; Timson, D. J.

    2010-01-01

    a further enhancement due to their annihilation at the end of the path. The work presented here aimed to establish and validate an experimental procedure for the quantification of plasmid and genomic DNA damage resulting from antiproton exposure. Immunocytochemistry was used to assess DNA damage in directly......Radiotherapy employs ionizing radiation to induce lethal DNA lesions in cancer cells while minimizing damage to healthy tissues. Due to their pattern of energy deposition, better therapeutic outcomes can, in theory, be achieved with ions compared to photons. Antiprotons have been proposed to offer...... and indirectly exposed human fibroblasts irradiated in both plateau and Bragg peak regions of a 126 MeV antiproton beam at CERN. Cells were stained post irradiation with an anti-γ-H2AX antibody. Quantification of the γ-H2AX foci-dose relationship is consistent with a linear increase in the Bragg peak region...

  3. Measurement of the antiproton-nucleus annihilation cross-section at low energy

    Science.gov (United States)

    Aghai-Khozani, H.; Bianconi, A.; Corradini, M.; Hayano, R.; Hori, M.; Leali, M.; Lodi Rizzini, E.; Mascagna, V.; Murakami, Y.; Prest, M.; Vallazza, E.; Venturelli, L.; Yamada, H.

    2018-02-01

    Systematic measurements of the annihilation cross sections of low energy antinucleons were performed at CERN in the 80's and 90's. However the antiproton data on medium-heavy and heavy nuclear targets are scarce. The ASACUSA Collaboration at CERN has measured the antiproton annihilation cross section on carbon at 5.3 MeV: the value is (1.73 ± 0.25) barn. The result is compared with the antineutron experimental data and with the theoretical previsions.

  4. Experimental setup and first measurement of DNA damage induced along and around an antiproton beam

    International Nuclear Information System (INIS)

    Kavanagh, J.N.; Currell, F.J.; Prise, K.M.; Schettino, G.; Currell, F.J.; Timson, D.J.; Holzscheiter, M.H.; Bassler, N.; Herrmann, R.

    2010-01-01

    Radiotherapy employs ionizing radiation to induce lethal DNA lesions in cancer cells while minimizing damage to healthy tissues. Due to their pattern of energy deposition, better therapeutic outcomes can, in theory, be achieved with ions compared to photons. Antiprotons have been proposed to offer a further enhancement due to their annihilation at the end of the path. The work presented here aimed to establish and validate an experimental procedure for the quantification of plasmid and genomic DNA damage resulting from antiproton exposure. Immunocytochemistry was used to assess DNA damage in directly and indirectly exposed human fibroblasts irradiated in both plateau and Bragg peak regions of a 126 MeV antiproton beam at CERN. Cells were stained post irradiation with an anti-γ-H2AX antibody. Quantification of the γ-H2AX foci-dose relationship is consistent with a linear increase in the Bragg peak region. A qualitative analysis of the foci detected in the Bragg peak and plateau region indicates significant differences highlighting the different severity of DNA lesions produced along the particle path. Irradiation of desalted plasmid DNA with 5 Gy antiprotons at the Bragg peak resulted in a significant portion of linear plasmid in the resultant solution. (authors)

  5. Measurement of 0.25-3.2 GeV antiprotons in the cosmic radiation

    DEFF Research Database (Denmark)

    Mitchell, J.W.; Barbier, L.M.; Christian, E.R.

    1996-01-01

    The balloon-borne Isotope Matter-Antimatter Experiment (IMAX) was flown from Lynn Lake, Manitoba, Canada on 16-17 July 1992. Using velocity and magnetic rigidity to determine mass, we have directly measured the abundances of cosmic ray antiprotons and protons in the energy range from 0.25 to 3.2 ...

  6. Measurement of Antiproton-proton Cross-Sections at Low Antiproton Momenta

    CERN Multimedia

    2002-01-01

    The experiment is designed to measure four different cross sections in the momentum range 150~MeV/c to 600~MeV/c: 1)~~~~the differential elastic \\\\ \\\\ 2)~~~~the differential charge exchange\\\\ \\\\ 3)~~~~the annihilation into charged and neutral pions\\\\ \\\\ 4)~~~~and the total cross section via the optical theorem. \\\\ \\\\ The experiment allows one to search once again and with good precision for baryonium. Of special interest is the existence of the S-meson, for which a signal of about 20~MeV-mb was found in a 1981 experiment (performed in the East Hall).\\\\ \\\\ A second point of special interest is the momentum region below 300~MeV/c because the cross sections are basically unknown. We will be able to explore the momentum dependence of this region for the first time.\\\\ \\\\ The elastic cross section is measured by a cylindrical multiwire proportional chamber and a scintillator hodoscope placed around a scattering chamber under vacuum. The charge exchange cross section is measured by a ring of 32~anti-neutron detector...

  7. Nuclear Excitations by Antiprotons and Antiprotonic Atoms

    CERN Multimedia

    2002-01-01

    The proposal aims at the investigation of nuclear excitations following the absorption and annihilation of stopped antiprotons in heavier nuclei and at the same time at the study of the properties of antiprotonic atoms. The experimental arrangement will consist of a scintillation counter telescope for the low momentum antiproton beam from LEAR, a beam degrader, a pion multiplicity counter, a monoisotopic target and Ge detectors for radiation and charged particles. The data are stored by an on-line computer.\\\\ \\\\ The Ge detectors register antiprotonic x-rays and nuclear @g-rays which are used to identify the residual nucleus and its excitation and spin state. Coincidences between the two detectors will indicate from which quantum state the antiprotons are absorbed and to which nuclear states the various reactions are leading. The measured pion multiplicity characterizes the annihilation process. Ge&hyphn. and Si-telescopes identify charged particles and determine their energies.\\\\ \\\\ The experiment will gi...

  8. Biological Effectiveness of Antiproton Annihilation

    DEFF Research Database (Denmark)

    Maggiore, C.; Agazaryan, N.; Bassler, N.

    2004-01-01

    from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The background, description, and status...

  9. Measurement of the Transverse Momentum of Dielectron Pairs in Proton - Anti-Proton Collisions

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Dylan Patrick [Univ. of Rochester, NY (United States)

    1997-01-01

    We present a measurement of the transverse momentum distribution of dielectron pairs with invariant mass near the mass of the Z boson. The data were obtained using the DO detector during the 1994-1995 run of the Tevatron Co!lider at Fermilab. The data used in the measurement corresponds to an integrated luminosity of 108.5 $pb^{-1}$ The measurement is compared to current phenomenology for vector boson production in proton-antiproton interactions, and the results are found to be consistent with expectation from Quantum Chromodynamics (QCD).

  10. Measurement of asymmetries and differential cross sections in antiproton-proton elastic scattering at momenta between 497 and 1550 MeV/c

    International Nuclear Information System (INIS)

    Kunne, R.A.

    1988-01-01

    An intermediate energy antiproton proton (anti pp) elastic scattering experiment is described. The data comprise a set of 15 measurements of the differential cross section and the asymmetry between 497 and 1550 MeV/c antiproton momentum. The measurements were carried out using the high quality antiproton beam provided by the Low Energy Antiproton Ring (LEAR) at CERN. A conventional polarized target was used, consisting of pentanol. The motivation for the measurements is the study of the anti pp interaction by providing data on the spin observable A on in a momentum range where it has never been measured before. 56 refs.; 55 figs.; 40 tabs

  11. Measurement of (anti)deuteron and (anti)proton production in DIS at HERA

    International Nuclear Information System (INIS)

    Chekanov, S.; Derrick, M.; Magill, S.

    2007-05-01

    The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300-318 GeV using an integrated luminosity of 120 pb -1 . The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3 T /M<0.7. The particle rates have been extracted and interpreted in terms of the coalescence model. The (anti)deuteron production yield is smaller than the (anti)proton yield by approximately three orders of magnitude, consistent with the world measurements. (orig.)

  12. Measurement of the Antiproton-Proton Total Cross-Section at the CERN ISR

    CERN Multimedia

    2002-01-01

    This experiment is a measurement of small angle scattering of antiprotons on protons and of protons on protons at 15/15, 22/22, 26/26 and 31/31 GeV, with the aim of obtaining data on the total cross-section for the scattering of protons on protons, and of determining the ratio of the real to the imaginary scattering amplitude at zero momentum transfer for antiprotons on protons. The measurement is divided into two parts: \\item 1) The measurement of @s^t^o^t(@*p) and @s^t^o^t(pp), using hodoscopes placed at small angles, outside the vacuum pipe, at approximately 9 metres from the intersection point. \\item 2) The measurement of the region in !t!, the momentum transfer squared, around the value !t^c!, where Coulomb and nuclear scattering are equal, in order to deduce the quantity @r = Re f(t=0)/Im f(t=0). This latter measurement is done by employi in earlier @s^t(pp) and @r experiments at the ISR. \\end{enumerate} In both set-ups the measurements are made by recording coincidences between collinear counters in th...

  13. Measurements of X-rays from antiprotonic helium

    Energy Technology Data Exchange (ETDEWEB)

    Baker, C.A.; Batty, C.J.; Moir, J.; Sakamoto, S.; Davies, J.D.; Lowe, J.; Nelson, J.M.; Pyle, G.J.; Squier, G.T.A.; Welsh, R.E.

    1989-04-17

    The absolute yields of X-rays from anti pHe atoms for 14 transitions covering the L, M and N series have been measured at target gas densities of 0.125, 0.25, 0.92, 1.0, 1.23, 2.0, 3.0 and 10.0 rho/sub STP/ and compared with the predictions of cascade calculations. The strong interaction width of the 3d state, has been determined to be 2.07+-0.11 meV.

  14. Biological effectiveness of antiproton annihilation

    CERN Document Server

    Holzscheiter, Michael H.; Bassler, Niels; Beyer, Gerd; De Marco, John J.; Doser, Michael; Ichioka, Toshiyasu; Iwamoto, Keisuke S.; Knudsen, Helge V.; Landua, Rolf; Maggiore, Carl; McBride, William H.; Møller, Søren Pape; Petersen, Jorgen; Smathers, James B.; Skarsgard, Lloyd D.; Solberg, Timothy D.; Uggerhøj, Ulrik I.; Withers, H.Rodney; Vranjes, Sanja; Wong, Michelle; Wouters, Bradly G.

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in “biological dose” in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current status of the experiment are given.

  15. Biological effectiveness of antiproton annihilation

    DEFF Research Database (Denmark)

    Holzscheiter, M.H.; Agazaryan, N.; Bassler, Niels

    2004-01-01

    We describe an experiment designed to determine whether or not the densely ionizing particles emanating from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct...... measurement of the biological effects of antiproton annihilation. The experiment has been approved by the CERN Research Board for running at the CERN Antiproton Decelerator (AD) as AD-4/ACE (Antiproton Cell Experiment) and has begun data taking in June of 2003. The background, description and the current...

  16. Measurement of antiproton production in $p$He collisions at $\\sqrt{s_{\\scriptscriptstyle\\rm NN}}=110$ GeV

    CERN Document Server

    The LHCb Collaboration

    2017-01-01

    The antiproton production cross-section in collisions of a 6.5 TeV LHC proton beam on helium at rest is measured by the LHCb experiment using the SMOG internal gas target from a dataset corresponding to an integrated luminosity of 0.4 $\\text{nb}^{-1}$. This is the first direct measurement of antimatter production in $p$He collisions, and has important implications for the interpretation of recent results from the PAMELA and AMS-02 experiments, which measure the antiproton component in cosmic rays outside of the Earth's atmosphere.

  17. Antiproton charge radius

    Science.gov (United States)

    Crivelli, P.; Cooke, D.; Heiss, M. W.

    2016-09-01

    The upcoming operation of the extra low energy antiprotons ring at CERN, the upgrade of the antiproton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of 1 08 e+ /s will open the possibility for new experiments with antihydrogen (H ¯). Here we propose a scheme to measure the Lamb shift of H ¯. For four months of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of C P T and the first determination of the antiproton charge radius at the level of 10%.

  18. Measurement of small-angle antiproton-proton and proton-proton elastic scattering at the CERN intersecting storage rings

    NARCIS (Netherlands)

    Amos, N.; Block, M.M.; Bobbink, G.J.; Botje, M.A.J.; Favart, D.; Leroy, C.; Linde, F.; Lipnik, P.; Matheys, J-P.; Miller, D.

    1985-01-01

    Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at . Using the optical theorem, total cross sections are obtained with an accuracy of about

  19. New Experiments with Antiprotons

    Science.gov (United States)

    Kaplan, D. M.

    2011-12-01

    Fermilab operates the world's most intense antiproton source. Recently proposed experiments can use those antiprotons either parasitically during Teva-tron Collider running or after the Tevatron Collider finishes in about 2011. For example, the annihilation of 8 GeV antiprotons might make the world's most intense source of tagged D0 mesons, and thus the best near-term opportunity to study charm mixing and search for new physics via its CP-violation signature. Other possible precision measurements include properties of the X(3872) and the charmonium system. An experiment using a Penning trap and an atom interferometer could make the world's first measurement of the gravitational force on antimatter. These and other potential measurements using antiprotons could yield a broad physics program at Fermilab in the post-Tevatron era.

  20. Sixfold improved single particle measurement of the magnetic moment of the antiproton

    CERN Document Server

    Nagahama, H; Sellner, S; Harrington, J; Higuchi, T; Borchert, M J; Tanaka, T; Besirli, M; Mooser, A; Schneider, G; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; Ulmer, S

    2017-01-01

    Our current understanding of the Universe comes, among others, from particle physics and cosmology. In particle physics an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, a striking matter/antimatter imbalance is observed. This contradiction inspires comparisons of the fundamental properties of particles and antiparticles with high precision. Here we report on a measurement of the g-factor of the antiproton with a fractional precision of 0.8 parts per million at 95% confidence level. Our value /2=2.7928465(23) outperforms the previous best measurement by a factor of 6. The result is consistent with our proton g-factor measurement gp/2=2.792847350(9), and therefore agrees with the fundamental charge, parity, time (CPT) invariance of the Standard Model of particle physics. Additionally, our result improves coefficients of the standard model extension which discusses the sensitivity of experiments with respect to CPT violation by up to a factor of 20.

  1. A parts-per-billion measurement of the antiproton magnetic moment

    Science.gov (United States)

    Smorra, C.; Sellner, S.; Borchert, M. J.; Harrington, J. A.; Higuchi, T.; Nagahama, H.; Tanaka, T.; Mooser, A.; Schneider, G.; Bohman, M.; Blaum, K.; Matsuda, Y.; Ospelkaus, C.; Quint, W.; Walz, J.; Yamazaki, Y.; Ulmer, S.

    2017-10-01

    Precise comparisons of the fundamental properties of matter–antimatter conjugates provide sensitive tests of charge–parity–time (CPT) invariance, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons, leptons and baryons have compared different properties of matter–antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron. Here we report a high-precision measurement of in units of the nuclear magneton μN with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic multi-Penning trap system. Our result  = ‑2.7928473441(42)μN (where the number in parentheses represents the 68% confidence interval on the last digits of the value) improves the precision of the previous best measurement by a factor of approximately 350. The measured value is consistent with the proton magnetic moment, μp = 2.792847350(9)μN, and is in agreement with CPT invariance. Consequently, this measurement constrains the magnitude of certain CPT-violating effects to below 1.8 × 10‑24 gigaelectronvolts, and a possible splitting of the proton–antiproton magnetic moments by CPT-odd dimension-five interactions to below 6 × 10‑12 Bohr magnetons.

  2. A parts-per-billion measurement of the antiproton magnetic moment.

    Science.gov (United States)

    Smorra, C; Sellner, S; Borchert, M J; Harrington, J A; Higuchi, T; Nagahama, H; Tanaka, T; Mooser, A; Schneider, G; Bohman, M; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; Ulmer, S

    2017-10-18

    Precise comparisons of the fundamental properties of matter-antimatter conjugates provide sensitive tests of charge-parity-time (CPT) invariance, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons, leptons and baryons have compared different properties of matter-antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron. Here we report a high-precision measurement of in units of the nuclear magneton μ N with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic multi-Penning trap system. Our result  = -2.7928473441(42)μ N (where the number in parentheses represents the 68% confidence interval on the last digits of the value) improves the precision of the previous best measurement by a factor of approximately 350. The measured value is consistent with the proton magnetic moment, μ p  = 2.792847350(9)μ N , and is in agreement with CPT invariance. Consequently, this measurement constrains the magnitude of certain CPT-violating effects to below 1.8 × 10 -24 gigaelectronvolts, and a possible splitting of the proton-antiproton magnetic moments by CPT-odd dimension-five interactions to below 6 × 10 -12 Bohr magnetons.

  3. Measurement of (anti)deuteron and (anti)proton production in DIS at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2007-05-15

    The first observation of (anti)deuterons in deep inelastic scattering at HERA has been made with the ZEUS detector at a centre-of-mass energy of 300-318 GeV using an integrated luminosity of 120 pb{sup -1}. The measurement was performed in the central rapidity region for transverse momentum per unit of mass in the range 0.3anti)proton yield by approximately three orders of magnitude, consistent with the world measurements. (orig.)

  4. Antiprotonic-hydrogen atoms

    International Nuclear Information System (INIS)

    Batty, C.J.

    1989-07-01

    Experimental studies of antiprotonic-hydrogen atoms have recently made great progress following the commissioning of the low energy antiproton facility (LEAR) at CERN in 1983. At the same time our understanding of the atomic cascade has increased considerably through measurements of the X-ray spectra. The life history of the p-bar-p atom is considered in some detail, from the initial capture of the antiproton when stopping in hydrogen, through the atomic cascade with the emission of X-rays, to the final antiproton annihilation and production of mesons. The experiments carried out at LEAR are described and the results compared with atomic cascade calculations and predictions of strong interaction effects. (author)

  5. Antiprotons in the ISR

    International Nuclear Information System (INIS)

    Bryant, P.J.

    1983-01-01

    A brief account is given of the events leading up to antiprotons in the Intersecting Storage Rings (ISR) followed by a synopsis of the characteristics and parameters of the physics runs made to date. Experience gained with critical operations, such as transfer line steering, injection optimization, stacking and phase displacement acceleration is reviewed bearing in mind the extremely low beam intensities. Special reference is made to the various machine improvements, namely the vertical transverse stochastic cooling for proton beams of up to 12 A, the transverse and longitudinal stochastic cooling for the antiprotons, the new antiproton beam position monitoring system in the transfer lines and ring and the use of two high-luminosity insertions. At the end of June 1982, a scheme for reaching higher luminosities by making multiple transfers from the Antiproton Accumulator (AA) and using longitudinal stochastic cooling in the ISR was demonstrated. The absence of any measurable loss rate during long periods of stable beam conditions has been used to set a new lower limit of 1000 h on the antiproton lifetime at rest. Finally, preparations are in progress to collide 3.5 to 6.5 GeV/c antiprotons with a hydrogen gas jet target

  6. Antiprotonic helium

    CERN Multimedia

    Eades, John

    2005-01-01

    An exotic atom in w hich an electron and an antiproton orbit a helium nucleus could reveal if there are any differences between matter and antimatter. The author describes this unusual mirror on the antiworld (5 pages)

  7. The relative biological effectiveness of antiprotons

    DEFF Research Database (Denmark)

    Holzscheiter, Michael H.; Alsner, Jan; Bassler, Niels

    2016-01-01

    of the relative biological effectiveness (RBE) of antiprotons near the end of range. We have performed the first-ever direct measurement of the RBE of antiprotons both at rest and in flight. Materials and methods: Experimental data were generated on the RBE of an antiproton beam entering a tissue-like target...

  8. A parts-per-billion measurement of the antiproton magnetic moment

    CERN Document Server

    Smorra, C; Borchert, M J; Harrington, J A; Higuchi, T; Nagahama, H; Tanaka, T; Mooser, A; Schneider, G; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; Ulmer, S

    2016-01-01

    Precise comparisons of the fundamental properties of matter–antimatter conjugates provide sensitive tests of charge–parity–time (CPT) invariance1, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons2, leptons3, 4 and baryons5, 6 have compared different properties of matter–antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level7, 8: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron3. Here we report a high-precision measurement of in units of the nuclear magneton μN with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic ...

  9. Precision Measurement of the Energies and Line Shapes of Antiprotonic Lyman and Balmer Transitions From Hydrogen and Helium Isotopes

    CERN Multimedia

    2002-01-01

    % PS207 \\\\ \\\\ For the study of the antiproton-proton and antiproton-nuclear spin-spin and spin-orbital interaction at threshold a high resolution measurement is proposed of the line shapes and energy shifts of antiprotonic K$\\alpha$ and L$\\alpha$ transitions of hydrogen and helium isotopes. The intense LEAR beam, stopped in the cyclotron trap at low gas pressure, provides a unique~X-ray~source with sufficient brightness. Charge coupled devices with their excellent background rejection and energy resolution allow a precise determination of the strong shifts and widths of the 1s hyperfine states of protonium, in addition the detection of the $\\bar{p}$D K$\\alpha$ transition should be possible. A focussing crystal spectrometer with a resolution $\\Delta$E/E of about l0$ ^- ^{4} $, which is superior in the accuracy of the energy determination by two orders of magnitude as compared to the present detection methods, will be used to measure the energies of the L$\\alpha$ transitions. This permits a first direct measure...

  10. CrossRef Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

    CERN Document Server

    Aguilar, M; Alpat, B; Ambrosi, G; Arruda, L; Attig, N; Aupetit, S; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Başeǧmez-du Pree, S; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bindi, V; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Boschini, M  J; Bourquin, M; Bueno, E  F; Burger, J; Cadoux, F; Cai, X  D; Capell, M; Caroff, S; Casaus, J; Castellini, G; Cernuda, I; Cervelli, F; Chae, M  J; Chang, Y  H; Chen, A  I; Chen, G  M; Chen, H  S; Cheng, L; Chou, H  Y; Choumilov, E; Choutko, V; Chung, C  H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Creus, W; Crispoltoni, M; Cui, Z; Dai, Y  M; Delgado, C; Della Torre, S; Demirköz, M  B; Derome, L; Di Falco, S; Dimiccoli, F; Díaz, C; von Doetinchem, P; Dong, F; Donnini, F; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eronen, T; Feng, J; Fiandrini, E; Finch, E; Fisher, P; Formato, V; Galaktionov, Y; Gallucci, G; García, B; García-López, R  J; Gargiulo, C; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Giovacchini, F; Goglov, P; Gómez-Coral, D  M; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guerri, I; Guo, K  H; Habiby, M; Haino, S; Han, K  C; He, Z  H; Heil, M; Hoffman, J; Hsieh, T  H; Huang, H; Huang, Z  C; Huh, C; Incagli, M; Ionica, M; Jang, W  Y; Jinchi, H; Kang, S  C; Kanishev, K; Kim, G  N; Kim, K  S; Kirn, Th; Konak, C; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M  S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H  T; Lee, S  C; Leluc, C; Li, H  S; Li, J  Q; Li, Q; Li, T  X; Li, W; Li, Z  H; Li, Z  Y; Lim, S; Lin, C  H; Lipari, P; Lippert, T; Liu, D; Liu, Hu; Lu, S  Q; Lu, Y  S; Luebelsmeyer, K; Luo, F; Luo, J  Z; Lv, S  S; Majka, R; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D  C; Morescalchi, L; Mott, P; Nelson, T; Ni, J  Q; Nikonov, N; Nozzoli, F; Nunes, P; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Pauluzzi, M; Pensotti, S; Pereira, R; Picot-Clemente, N; Pilo, F; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Putze, A; Quadrani, L; Qi, X  M; Qin, X; Qu, Z  Y; Räihä, T; Rancoita, P  G; Rapin, D; Ricol, J  S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Schael, S; Schmidt, S  M; Schulz von Dratzig, A; Schwering, G; Seo, E  S; Shan, B  S; Shi, J  Y; Siedenburg, T; Son, D; Song, J  W; Sun, W  H; Tacconi, M; Tang, X  W; Tang, Z  C; Tao, L; Tescaro, D; Ting, Samuel C  C; Ting, S  M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vázquez Acosta, M; Vecchi, M; Velasco, M; Vialle, J  P; Vitale, V; Vitillo, S; Wang, L  Q; Wang, N  H; Wang, Q  L; Wang, X; Wang, X  Q; Wang, Z  X; Wei, C  C; Weng, Z  L; Whitman, K; Wienkenhöver, J; Willenbrock, M; Wu, H; Wu, X; Xia, X; Xiong, R  Q; Xu, W; Yan, Q; Yang, J; Yang, M; Yang, Y; Yi, H; Yu, Y  J; Yu, Z  Q; Zeissler, S; Zhang, C; Zhang, J; Zhang, J  H; Zhang, S  D; Zhang, S  W; Zhang, Z; Zheng, Z  M; Zhu, Z  Q; Zhuang, H  L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P

    2016-01-01

    A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×105 antiproton events and 2.42×109 proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p¯, proton p, and positron e+ fluxes are found to have nearly identical rigidity dependence and the electron e− flux exhibits a different rigidity dependence. Below 60 GV, the (p¯/p), (p¯/e+), and (p/e+) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p¯/p), (p¯/e+), and (p/e+) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

  11. Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station.

    Science.gov (United States)

    Aguilar, M; Ali Cavasonza, L; Alpat, B; Ambrosi, G; Arruda, L; Attig, N; Aupetit, S; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Başeǧmez-du Pree, S; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bindi, V; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Boschini, M J; Bourquin, M; Bueno, E F; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, G M; Chen, H S; Cheng, L; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Creus, W; Crispoltoni, M; Cui, Z; Dai, Y M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Dimiccoli, F; Díaz, C; von Doetinchem, P; Dong, F; Donnini, F; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eronen, T; Feng, J; Fiandrini, E; Finch, E; Fisher, P; Formato, V; Galaktionov, Y; Gallucci, G; García, B; García-López, R J; Gargiulo, C; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Giovacchini, F; Goglov, P; Gómez-Coral, D M; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kang, S C; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Konak, C; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H S; Li, J Q; Li, J Q; Li, Q; Li, T X; Li, W; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, Hu; Lu, S Q; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Nelson, T; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Pauluzzi, M; Pensotti, S; Pereira, R; Picot-Clemente, N; Pilo, F; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Putze, A; Quadrani, L; Qi, X M; Qin, X; Qu, Z Y; Räihä, T; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Schael, S; Schmidt, S M; Schulz von Dratzig, A; Schwering, G; Seo, E S; Shan, B S; Shi, J Y; Siedenburg, T; Son, D; Song, J W; Sun, W H; Tacconi, M; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türkoğlu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vázquez Acosta, M; Vecchi, M; Velasco, M; Vialle, J P; Vitale, V; Vitillo, S; Wang, L Q; Wang, N H; Wang, Q L; Wang, X; Wang, X Q; Wang, Z X; Wei, C C; Weng, Z L; Whitman, K; Wienkenhöver, J; Willenbrock, M; Wu, H; Wu, X; Xia, X; Xiong, R Q; Xu, W; Yan, Q; Yang, J; Yang, M; Yang, Y; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, C; Zhang, J; Zhang, J H; Zhang, S D; Zhang, S W; Zhang, Z; Zheng, Z M; Zhu, Z Q; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P

    2016-08-26

    A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.

  12. The CERN antiproton programme

    International Nuclear Information System (INIS)

    Herr, H.

    1979-01-01

    A diagram and basic parameters of the ICE (Initial Cooling Experiment) storage ring constructed in CERN are examined. The experimental results of stochastic and electron cooling and the results of measuring of the antiproton lifetime are discussed. The main parameters of the antiproton storage are listed. Comparison between stochastic and electron cooling has shown that the latter is characterized by shorter cooling time independent of the particle number in a beam. Advantage of stochastic cooling lies in its possible usage at higher energies [ru

  13. Antiproton Target

    CERN Multimedia

    1980-01-01

    Antiproton target used for the AA (antiproton accumulator). The first type of antiproton production target used from 1980 to 1982 comprised a rod of copper 3mm diameter and 120mm long embedded in a graphite cylinder that was itself pressed into a finned aluminium container. This assembly was air-cooled and it was used in conjunction with the Van der Meer magnetic horn. In 1983 Fermilab provided us with lithium lenses to replace the horn with a view to increasing the antiproton yield by about 30%. These lenses needed a much shorter target made of heavy metal - iridium was chosen for this purpose. The 50 mm iridium rod was housed in an extension to the original finned target container so that it could be brought very close to the entrance to the lithium lens. Picture 1 shows this target assembly and Picture 2 shows it mounted together with the lithium lens. These target containers had a short lifetime due to a combination of beam heating and radiation damage. This led to the design of the water-cooled target in...

  14. Measurement of the Antiprotonic Lyman- and Balmer X-rays of $\\overline{p}H$ and $\\overline{p}D$ Atoms at Very Low Target Pressures

    CERN Multimedia

    2002-01-01

    The aim of this experiment is to measure the energies and intensities of the n @A 1 (Lyman) and n @A 2 (Balmer) tansitions with high accuracy in both @*H and @*D, from which the strong interaction effects of the 1s- and 2p-level can be extracted. These observables may be related to the antiproton-proton and antiproton-neutron scattering length. \\\\ \\\\ Since in these targets collisional Stark effect occurs, we will stop the antiprotons in extreme thin gaseous targets (pressure as low as 10 Torr), where no Stark effect occurs and the 2-1 transition is favoured. In order to use antiprotons with high efficiency despite of the low target density, we will trap antiprotons of a momentum of 100 MeV/c in a magnetic field of cyclotron characteristics. The antiprotons are decelerated by their energy loss in the target gas. The focusing properties of the magnetic field serve to compensate the multiple scattering and we will end up with a concentrated stopping distribution at the centre. Due to the long orbiting time, back...

  15. Coincidence studies with antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2010-02-01

    We present a short overview of a new method for calculating fully differential cross sections that is able to describe any aspect of coincidence measurements involving heavy projectiles. The method is based upon impact parameter close coupling with pseudostates. Examples from antiproton impact ionization are shown.

  16. A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90°

    Science.gov (United States)

    Hu, Q.; Bechstedt, U.; Gillitzer, A.; Grzonka, D.; Khoukaz, A.; Klehr, F.; Lehrach, A.; Prasuhn, D.; Ritman, J.; Sefzick, T.; Stockmanns, T.; Täschner, A.; Wuestner, P.; Xu, H.

    2014-10-01

    The design and construction of a recoil detector for the measurement of recoil protons of antiproton-proton elastic scattering at scattering angles close to are described. The performance of the recoil detector has been tested in the laboratory with radioactive sources and at COSY with proton beams by measuring proton-proton elastic scattering. The results of laboratory tests and commissioning with beam are presented. Excellent energy resolution and proper working performance of the recoil detector validate the conceptual design of the KOALA experiment at HESR to provide the cross section data needed to achieve a precise luminosity determination at the PANDA experiment.

  17. Antiprotons are another matter

    International Nuclear Information System (INIS)

    Hynes, M.V.

    1987-01-01

    Theories of gravity abound, whereas experiments in gravity are few in number. An important experiment in gravity that has not been performed is the measurement of the gravitational acceleration of antimatter. Although there have been attempts to infer these properties from those of normal matter, none of these theoretical arguments are compelling. Modern theories of gravity that attempt to unify gravity with the other forces of nature predict that in principle antimatter can fall differently than normal matter in the Earth's field. Some of these supergravity theories predict that antimatter will fall faster, and that normal matter will fall with a small Baryon-number dependance in the earth's field. All of these predictions violate the Weak Equivalence Principle, a cornerstone of General Relativity, but are consistent with CPT conservation. In our approved experiment at LEAR (PS-200) we will test the Weak Equivalence Principle for antimatter by measuring the gravitational acceleration of the antiproton. Through a series of deceleration stages, antiprotons from LEAR will be lowered in energy to ∼4 Kelvin at which energy the gravitational effect will be measureable. The measurement will employ the time-of-flight technique wherein the antiprotons are released vertically in a drift tube. The spectrum of time-of-flight measurements can be used to extract the gravitational acceleration experienced by the particles. The system will be calibrated using H - ions which simulates the electromagnetic behavior of the antiproton, yet is a baryon to ∼0.1%. To extract the gravitational acceleration of the antiproton relative to the H - ion with a statistical precision of 1% will require the release of ∼10 6 to 10 7 particles

  18. A reservoir trap for antiprotons

    CERN Document Server

    Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

    2015-01-01

    We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

  19. Measurement of the antiproton-proton total cross section at √s =546 and 1800 GeV

    International Nuclear Information System (INIS)

    Abe, F.; Albrow, M.; Amidei, D.; Anway-Wiese, C.; Apollinari, G.; Atac, M.; Auchincloss, P.; Azzi, P.; Bacchetta, N.; Baden, A.R.; Badgett, W.; Bailey, M.W.; Bamberger, A.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Biery, K.; Bhadra, S.; Binkley, M.; Bisello, D.; Blair, R.; Blocker, C.; Bodek, A.; Bolognesi, V.; Booth, A.W.; Boswell, C.; Brandenburg, G.; Brown, D.; Buckley-Geer, E.; Budd, H.S.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Campagnari, C.; Campbell, M.; Caner, A.; Carey, R.; Carithers, W.; Carlsmith, D.; Carroll, J.T.; Cashmore, R.; Castro, A.; Cen, Y.; Cervelli, F.; Chadwick, K.; Chapman, J.; Chapin, T.J.; Chiarelli, G.; Chinowsky, W.; Cihangir, S.; Clark, A.G.; Cobal, M.; Connor, D.; Contreras, M.; Cooper, J.; Cordelli, M.; Crane, D.; Cunningham, J.D.; Day, C.; DeJongh, F.; Dell'Agnello, S.; Dell'Orso, M.; Demortier, L.; Denby, B.; Derwent, P.F.; Devlin, T.; Dickson, M.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Eno, S.; Errede, S.; Etchegoyen, A.; Farhat, B.; Frautschi, M.; Feldman, G.J.; Flaugher, B.; Foster, G.W.; Franklin, M.; Freeman, J.; Fuess, T.; Fukui, Y.; Garfinkel, A.F.; Gauthier, A.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Gold, M.; Gonzalez, J.; Goulianos, K.; Grassmann, H.; Grieco, G.M.; Grindley, R.; Grosso-Pilcher, C.; Grunhaus, J.; Haber, C.; Hahn, S.R.; Handler, R.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; Hessing, T.; Hollebeek, R.; Holloway, L.; Hoelscher, A.; Hong, S.; Houk, G.; Hu, P.; Hubbard, B.; Huffman, B.T.; Hughes, R.; Hurst, P.; Huth, J.; Hylen, J.; Incagli, M.; Ino, T.; Iso, H.; Jessop, C.P.; Johnson, R.P.; Joshi, U.; Kadel, R.W.; Kamon, T.; Kanda, S.; Kardelis, D.A.; Karliner, I.; Kearns, E.; Keeble, L.

    1994-01-01

    We report a measurement of the proton-antiproton total cross section σ T at c.m.s. energies √s =546 and 1800 GeV. Using the luminosity-independent method, we find σ T =61.26±0.93 mb at √s =546 GeV and 80.03±2.24 mb at √s =1800 GeV. In this energy range, the ratio σ el /σ T increases from 0.210±0.002 to 0.246±0.004

  20. Measurement of small angle antiproton-proton elastic scattering at √s =546 and 1800 GeV

    International Nuclear Information System (INIS)

    Abe, F.; Albrow, M.; Amidei, D.; Anway-Wiese, C.; Apollinari, G.; Atac, M.; Auchincloss, P.; Azzi, P.; Bacchetta, N.; Baden, A.R.; Badgett, W.; Bailey, M.W.; Bamberger, A.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Biery, K.; Bhadra, S.; Binkley, M.; Bisello, D.; Blair, R.; Blocker, C.; Bodek, A.; Bolognesi, V.; Booth, A.W.; Boswell, C.; Brandenburg, G.; Brown, D.; Buckley-Geer, E.; Budd, H.S.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Campagnari, C.; Campbell, M.; Caner, A.; Carey, R.; Carithers, W.; Carlsmith, D.; Carroll, J.T.; Cashmore, R.; Castro, A.; Cen, Y.; Cervelli, F.; Chadwick, K.; Chapman, J.; Chapin, T.J.; Chiarelli, G.; Chinowsky, W.; Cihangir, S.; Clark, A.G.; Cobal, M.; Connor, D.; Contreras, M.; Cooper, J.; Cordelli, M.; Crane, D.; Cunningham, J.D.; Day, C.; DeJongh, F.; Dell'Agnello, S.; Dell'Orso, M.; Demortier, L.; Denby, B.; Derwent, P.F.; Devlin, T.; Dickson, M.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Eno, S.; Errede, S.; Etchegoyen, A.; Farhat, B.; Frautschi, M.; Feldman, G.J.; Flaugher, B.; Foster, G.W.; Franklin, M.; Freeman, J.; Fuess, T.; Fukui, Y.; Garfinkel, A.F.; Gauthier, A.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Gold, M.; Gonzalez, J.; Goulianos, K.; Grassmann, H.; Grieco, G.M.; Grindley, R.; Grosso-Pilcher, C.; Haber, C.; Hahn, S.R.; Handler, R.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; Hessing, T.; Hollebeek, R.; Holloway, L.; Hoelscher, A.; Hong, S.; Houk, G.; Hu, P.; Hubbard, B.; Huffman, B.T.; Hughes, R.; Hurst, P.; Huth, J.; Hylen, J.; Incagli, M.; Ino, T.; Iso, H.; Jessop, C.P.; Johnson, R.P.; Joshi, U.; Kadel, R.W.; Kamon, T.; Kanda, S.; Kardelis, D.A.; Karliner, I.; Kearns, E.; Keeble, L.; Kephart, R.; Kesten, P.

    1994-01-01

    Antiproton-proton elastic scattering was measured at c.m.s. energies √s =546 and 1800 GeV in the range of four-momentum transfer squared 0.025 2 . The data are well described by the exponential form e bt with a slope b=15.28±0.58 (16.98±0.25) GeV -2 at √s =546 (1800) GeV. The elastic scattering cross sections are, respectively, σ el =12.87±0.30 and 19.70±0.85 mb

  1. Measurements of Wake-Riding Electrons in Antiproton-Carbon-Foil Collisions

    CERN Multimedia

    2002-01-01

    When a charged particle passes through dielectric media, e.g. a thin carbon foil, a ``wake'' is induced. The characteristic wake-potential shows an oscillatory behaviour, with a wavelength of about $ 2 \\pi v _{p} / \\omega _{p} _{l} $ where $ v _{p} $ is the projectile velocity and $ \\omega _{p} _{l} $ the plasmon energy of the target. This induced wake potential is superimposed on the Coulomb potential of the projectile, the latter leading to a pronounced ``cusp'' of electrons leaving the solid at $ v _{e} app v _{p} $ for positively charged projectiles in the MeV region. Correspondingly, an ``anti-cusp'' is expected for antiprotons. \\\\ \\\\ In the solid, the wake-potential leads to an attractive force on electrons, and a dynamic electronic state is predicted both for proton and antiproton projectiles. In the solid, the wake-riding electrons are travelling with the projectile speed $ v _{p} $ Upon exit of the foil, the electron released from the wake-riding state of an antiproton will suddenly find itself in th...

  2. Unified interpretation of cosmic-ray nuclei and antiproton recent measurements

    International Nuclear Information System (INIS)

    Di Bernardo, Giuseppe; Gaggero, Daniele; Evoli, Carmelo; Grasso, Dario; Maccione, Luca

    2009-09-01

    We use our numerical code, DRAGON, to study the implications and the impact of recent CREAM and PAMELA data on our knowledge of the propagation properties of cosmic ray nuclei with energy >or similar 1 GeV/n in the Galaxy. We will show that B/C (as well as N/O and C/O) and anti p/p data (especially including recent PAMELA results) can consistently be matched within a unique diffusion-reacceleration model. The requirement that light nuclei and anti p data are both reproduced within experimental uncertainties places stringent limits on suitable propagation parameters. In particular, we find the allowed range of the diffusion coefficient spectral index to be 0.38 A ≅15 kms -1 ) is allowed. Furthermore, we do not need to introduce any ad hoc break in the injection spectrum of primary cosmic rays. If antiproton data are not used to constrain the propagation parameters, a larger set of models is allowed. In this case, we determine which combinations of the relevant parameters maximize and minimize the antiproton flux under the condition of still fitting light nuclei data at 95% C.L. These models may then be used to constrain a possible extra antiproton component arising from astrophysical or exotic sources (e.g. dark matter annihilation or decay). (orig.)

  3. Antiproton Cancer Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels

    Antiprotons are interesting as a modality in radiation therapy for the following reasons: When fast antiprotons penetrate matter, they behave as protons. Well before the Bragg-peak, protons and antiprotons have near identical stopping powers exhibit equal radiobiology. But when the antiprotons co...

  4. Profile measurements by ondulator radiation of proton and anti-proton beams

    International Nuclear Information System (INIS)

    Meot, F.

    1981-12-01

    The CERN SPS synchrotron is presently under transformation in a proton-antiproton storage ring. As part of this plan, circulating beams must be adjusted. After a first experiment of synchrotron radiation operation, reserved up to now to high intensity and high energy proton beams, a system, based on the use of light emitted by particles crossing the ondulator periodic magnetic field, is decided to be realized. Context and nature of this plan are presented in this thesis, together with details of elaboration and realization. To conclude, first experimental results on the proton ondulator radiation are presented [fr

  5. The biological effectiveness of antiproton irradiation

    DEFF Research Database (Denmark)

    Holzscheiter, Michael H.; Bassler, Niels; Agazaryan, Nzhde

    2006-01-01

    ever measurements of the biological effectiveness of antiprotons. Materials and methods: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7 MeV antiprotons, 48 MeV protons, or 60Co c-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose...... has a higher relative biological effectiveness (RBE). Conclusion: We have produced the first measurements of the biological consequences of antiproton irradiation. These data substantiate theoretical predictions of the biological effects of antiproton annihilation within the Bragg peak, and suggest...

  6. Antiproton Radiation Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael H.; Petersen, Jørgen B.B.

    2007-01-01

    the radiobiological properties using antiprotons at 50 and 125 MeV from the Antiproton Decelerator (AD) at CERN. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film. Radiobiological experiments were done with Chinese V79 WNRE hamster cells. Monte Carlo particle...... transport codes were investigated and compared with results obtained from the ionization chambers and alanine pellets. A track structure model have been applied on the calculated particle spectrum, and been used to predict the LET-dependent response of the alanine pellets. The particle transport program...... FLUKA produced data which were in excellent agreement with our ionization chamber measurements, and in good agreement with our alanine measurements. FLUKA is now being used to generate a wide range of depth dose data at several energies, including secondary particle–energy spectra, which will be used...

  7. The antiproton depth–dose curve in water

    CERN Document Server

    Bassler, N; Jäkel, O; Knudsen, H V; Kovacevic, S

    2008-01-01

    We have measured the depth–dose curve of 126 MeV antiprotons in a water phantom using ionization chambers. Since the antiproton beam provided by CERN has a pulsed structure and possibly carries a high-LET component from the antiproton annihilation, it is necessary to correct the acquired charge for ion recombination effects. The results are compared with Monte Carlo calculations and were found to be in good agreement. Based on this agreement we calculate the antiproton depth–dose curve for antiprotons and compare it with that for protons and find a doubling of the physical dose in the peak region for antiprotons.

  8. Entrance and peripheral dose measurements during radiotherapy

    International Nuclear Information System (INIS)

    Sulieman, A.; Kappas, K.; Theodorou, K.

    2008-01-01

    In vivo dosimetry of entrance dose was performed using thermoluminescent dosimeters (TLD) in order to evaluate the clinical application of the build up caps in patient dose measurements and for different treatment techniques. Peripheral dose (thyroid and skin) was measured for patients during breast radiotherapy to evaluate the probability of secondary cancer induction. TLD-100 chips were used with different Copper build up caps (for 6 MV and 15 MV photon beams from two linear accelerators. Entrance doses were measured for patients during radiotherapy course for breast, head and neck, abdomen and pelvis malignancies. The measured entrance dose for the different patients for 6 MV beams is found to be within the ±2.6% compared to the dose derived from theoretical estimation (normalized dose at D max ). The same measurements for 15 MV beams are found to be ±3 %. The perturbation value can reach up to 20% of the D max , which acts as a limitation for entrance dose measurements. An average thyroid skin dose of 3.7% of the prescribed dose was measured per treatment session while the mean skin dose breast treatment session is estimated to be 42% of D max , for both internal and external fields. These results are comparable in those of the in vivo of reported in literature. The risk of fatality due to thyroid cancer per treatment course is 3x10 -3

  9. Antiproton radiation found effective in cancer research

    CERN Multimedia

    2003-01-01

    "An international collaboration of scientists has completed the first ever antiproton beam experiments designed to reveal the biological effectiveness of antiproton radiation in terminating cells used for cancer research...PBar Labs assembled the collaboration at CERN (European Organization for Nuclear Research in Geneva) to perform the measurements" (1 page).

  10. Antiproton-nucleus scattering

    International Nuclear Information System (INIS)

    Shastry, C.S.

    1988-01-01

    The operation of low energy antiproton ring at CERN has initiated antiproton-nucleus(antip - A) collision experiments. These give information on antiproton-nucleon(antiproton - N) interaction in the nuclei, structure of antiprotonic atoms, antiprotonic bound states in the nucleus, strange particle production etc. Considerable data on antiproton - A scattering cross sections at several incident energies for targets like 12 C, 16 O, 18 Ca etc. have become available. Both elastic and inelastic antiproton-A cross sections show diffractive oscillatory behaviour. As a result, it is possible to qualitatively understand antiproton-A cross sections by treating the target as a black sphere with diffused surface. Phenomenological optical potentials including those generated by the model independent Fourier-Bessel method show that the potential is highly absorptive; imaginary part dominates and has longer range than real part and the latter decreases with energy. Spin-orbit term is less important. Some of these can be understood in terms of meson exchange antiproton-N potentials. The large imaginary part is due to the availability of additional channels initiated by antiproton annihilation. Optical potentials show several ambiguities including the Igo ambiguity. More fundamental approaches to the potential based on antiproton-N t matrix and folding models have been attempted. A comparison of heavy ion scatering and antiproton-A scattering is made. It is shown that semi-classical WKB method is applicable for antiproton-A scattering. Some recent work on antiproton-p potentials, antiprotonic states and strange particle production is discussed. (author). 28 refs., 10 figs., 7 tables

  11. The antiproton decelerator: AD

    International Nuclear Information System (INIS)

    Baird, S.; Berlin, D.; Boillot, J.; Bosser, J.; Brouet, M.; Buttkus, J.; Caspers, F.; Chohan, V.; Dekkers, D.; Eriksson, T.; Garoby, R.; Giannini, R.; Grobner, O.; Gruber, J.; Hemery, J.Y.; Koziol, H.; Maccaferri, R.; Maury, S.; Metzger, C.; Metzmacher, K.; Moehl, D.; Mulder, H.; Paoluzzi, M.; Pedersen, F.; Riunaud, J.P.; Serre, C.; Simon, D.J.; Tranquille, G.; Tuyn, J.; Williams, B.

    1997-01-01

    In view of a possible future programme of physics with low-energy antiprotons, a simplified scheme for the provision of antiprotons at 100 MeV/c has been studied. It uses the present target area and the modified antiproton collector (AC) in its present location. In this report the modifications and the operation are discussed. (orig.)

  12. Antiprotons get biological

    CERN Multimedia

    2003-01-01

    After its final run in September, the first results of the Antiproton Cell Experiment (ACE) look very promising. It was the first experiment to take data on the biological effects of antiproton beams to evaluate the potential of antiprotons in radiation therapy.

  13. Cosmic ray antiproton measurements in the 4-19 GeV energy range using the NMSU/WiZard-matter antimatter superconducting spectrometer 2 (MASS2)

    Energy Technology Data Exchange (ETDEWEB)

    Basini, G.; Bongiorno, F. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Brunetti, M.T.; Codini, A.; Grimani, C. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy)]|[INFN, Rome (Italy); Hof, M. [Siegen Univ. (Germany). Fachbereich Physik; Golden, R.L.; Stochaj, S.J. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Brancaccio, F.M. [Florence Univ. (Italy)]|[INFN, Florence (Italy)

    1995-09-01

    The p/p-ratio from 4 to 19 GeV has been measured using the NMSU/WiZard balloon borne matter antimatter superconducting spectrometer (MASS2) instrument. This is the first confirmation of the cosmic ray antiproton component made in this energy range since their discovery in 1979. The MASS2 instrument is an updated version of the instrument flown in 1979. The p/p- ratio is 1.52x10{sup -}4.

  14. High-precision spectroscopy of antiprotonic helium

    CERN Document Server

    Widmann, E

    2001-01-01

    We present first results of laser and microwave spectroscopy experiments of antiprotonic helium performed at the new Antiproton Decelerator (AD) at CERN. Extending a series of previous measurements done at the Low Energy Antiproton Ring (LEAR) of CERN, several laser- induced transitions of the antiproton in the exotic three-body system He/sup 2+/-e/sup -/-p could be determined with a precision down to 1.3*10/sup -7/. This constitutes an improvement of a factor 3 over previous measurements, and allows to test accurate three-body calculations of this system that include QED corrections. The observed agreement on the same level can be used to infer CPT limits on the antiproton charge and mass. Furthermore, a first indication of a resonance signal of a two-laser microwave triple experiment to measure the hyperfine splitting of antiprotonic helium could been observed. Such a measurement has the potential to determine the antiproton magnetic moment to a higher precision that it is known today. (19 refs).

  15. Treatment Plans for Antiproton Beams

    DEFF Research Database (Denmark)

    Holzscheiter, Michael; Bassler, Niels; Herrmann, Rochus

    from these measurements were used to benchmark the FLUKA Monte Carlo code, which then has been used for calculations of physical dose inside and outside of the primary antiproton beam. From clonogenic survival studies on the different cell lines mentioned above we have determined biological effective...

  16. Recent progress of laser spectroscopy experiments on antiprotonic helium

    Science.gov (United States)

    Hori, Masaki

    2018-03-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) collaboration is currently carrying out laser spectroscopy experiments on antiprotonic helium ? atoms at CERN's Antiproton Decelerator facility. Two-photon spectroscopic techniques have been employed to reduce the Doppler width of the measured ? resonance lines, and determine the atomic transition frequencies to a fractional precision of 2.3-5 parts in 109. More recently, single-photon spectroscopy of buffer-gas cooled ? has reached a similar precision. By comparing the results with three-body quantum electrodynamics calculations, the antiproton-to-electron mass ratio was determined as ?, which agrees with the known proton-to-electron mass ratio with a precision of 8×10-10. The high-quality antiproton beam provided by the future Extra Low Energy Antiproton Ring (ELENA) facility should enable further improvements in the experimental precision. This article is part of the Theo Murphy meeting issue `Antiproton physics in the ELENA era'.

  17. Measurement of electroweak single top quark production in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Peter Joseph [Univ. of California, Los Angeles, CA (United States)

    2008-01-01

    The top quark is an extremely massive fundamental particle that is predominantly produced in pairs at particle collider experiments. The Standard Model of particle physics predicts that top quarks can also be produced singly by the electroweak force; however, this process is more difficult to detect because it occurs at a smaller rate and is more difficult to distinguish from background processes. The cross section of this process is related to the Cabbibo-Kobayashi-Maskawa matrix element |V tb|, and measurement of the single top quark production cross section is currently the only method to directly measure this quantity without assuming the number of generations of fermions. This thesis describes a measurement of the cross section of electroweak single top quark production in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. This analysis uses 2.2 fb-1 of integrated luminosity recorded by the Collider Detector at Fermilab. The search is performed using a matrix element method which calculates the differential cross section for each event for several signal and background hypotheses. These numbers are combined into a single discriminant and used to construct templates from Monte Carlo simulation. A maximum likelihood fit to the data distribution gives a measurement of the cross section. This analysis measures a value of 2.2$+0.8\\atop{-0.7}$ pb, which corresponds to a value of |V tb| = 0.88$+0.16\\atop{-0.14}$experimental±0.7(theoretical). The probability that this result originates from a background fluctuation in the absence of single top production (p-value) is 0.0003, which is equivalent to 3.4 standard deviations in Gaussian statistics. The expected (median) p-value as estimated from pseudo-experiments for this analysis is 0.000003, which corresponds to 4.5 standard deviations in Gaussian statistics.

  18. ASACUSA hits antiproton jackpot

    CERN Multimedia

    2001-01-01

    The Japanese-European ASACUSA collaboration, which takes its name from the oldest district of Tokyo, approaches the antimatter enigma in a different way from the other two AD experiments, by inserting antiprotons into ordinary atoms. Last month the collaboration succeeded in trapping about a million antiprotons. The ASACUSA antiproton trap (lower cylinder), surmounted by its liquid helium reservoir. Looking on are Ken Yoshiki-Franzen, Zhigang Wang, Takahito Tasaki, Suzanne Reed, John Eades, Masaki Hori, Yasunori Yamazaki, Naofumi Kuroda, Jun Sakaguchi, Berti Juhasz, Eberhard Widmann and Ryu Hayano. A key element of the ASACUSA apparatus is its decelerating Radiofrequency Quadrupole magnet, RFQD. After tests with protons in Aarhus, this was installed in ASACUSA's antiproton beam last October (Bulletin 41/2000, 9 October 2000). Constructed by Werner Pirkl's group in PS Division, the RFQD works by applying an electric field to the AD antiproton pulse the opposite direction to its motion. As the antiprotons slo...

  19. Antiproton Cancer Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels

    . The stopping power of high-energetic antiprotons in tissue, is similar to that of protons. Most energy is lost per unit distance as the particle comes to rest, but when the antiprotons stops, each one will annihilate on a nuclei, releasing 1.9 GeV of energy. Most of this energy is carried away by pions, gamma...... rays and neutrons, but a part of the annihilation energy is still deposited locally as recoiling nuclear fragments with limited range. These fragments will also increase the relative biological effect at the annihilation vertex. We have masured the biological effect of an antiproton beam for the first...... to handle antiprotons. This will enable us to do treatment planning with antiprotons, and thereby bring us closer to answer the question of the potential clinical benefit of antiprotons....

  20. Physics at CERN's Antiproton Decelerator

    CERN Document Server

    Hori, M

    2013-01-01

    The Antiproton Decelerator of CERN began operation in 1999 to serve experiments for studies of CPT invariance by precision laser and microwave spectroscopy of antihydrogen ($\\bar{\\rm H}$) and antiprotonic helium ($\\bar{p}{\\rm He}^+$). The first 12 years of operation saw cold $\\bar{\\rm H}$ synthesized by overlapping clouds of positrons ($e^+$) and antiprotons ($\\bar{p}$) confined in magnetic Penning traps. Cold $\\bar{\\rm H}$ was also produced in collisions between Rydberg positronium atoms and $\\bar{p}$. Ground-state $\\bar{\\rm H}$ was later trapped for up to $\\sim 1000$ s in a magnetic bottle trap, and microwave transitions excited between its hyperfine levels. In the $\\bar{p}{\\rm He}^+$ atom, UV transitions were measured to a precision of (2.3-5) $\\times$ $10^{-9}$ by sub-Doppler two-photon laser spectroscopy. From this the antiproton-to-electron mass ratio was determined as $M_{\\bar{p}}/m_e=$1836.1526736(23), which agrees with the p value. Microwave spectroscopy of $\\bar{p}{\\rm He}^+$ yielded a measurement o...

  1. The CERN antiproton collector

    International Nuclear Information System (INIS)

    Autin, B.

    1984-01-01

    The Antiproton Collector is a new ring of much larger acceptance than the present accumulator. It is designed to receive 10 8 antiprotons per PS cycle. In order to be compatible with the Antiproton Accumulator, the momentum spread and the emittances are reduced from 6% to 0.2% and from 200 π mm mrad to 25 π mm mrad respectively. In addition to the ring itself, the new target area and the modifications to the stochastic systems of the Antiproton Accumulator are described. (orig.)

  2. Out-of-field dose measurements in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kaderka, Robert

    2011-07-13

    This thesis describes the results from measurements of the out-of-field dose in radiotherapy. The dose outside the treatment volume has been determined in a water phantom and an anthropomorphic phantom. Measurements were performed with linac photons, passively delivered protons, scanned protons, passively delivered carbon ions as well as scanned carbon ions. It was found that the use of charged particles for radiotherapy reduces the out-of-field dose by up to three orders of magnitude compared to conventional radiotherapy with photons.

  3. Objective measurements of radiotherapy-induced erythema.

    Science.gov (United States)

    Nyström, Josefina; Geladi, Paul; Lindholm-Sethson, Britta; Rattfelt, Jenny; Svensk, Ann-Christin; Franzen, Lars

    2004-11-01

    The development of acute radiation erythema is a common phenomenon among patients under-going radiotherapy treatment. Because of the absence of reliable objective classification methods, the degree of skin reaction can at present mainly be judged subjectively in the clinic. This has motivated the present preliminary study,concerning the first steps in the development of an objective method for skin reaction classification. Three non-invasive techniques were used:near-infrared (NIR) spectroscopy, laser Doppler perfusion imaging and digital photography. The NIR spectra were analysed with principal component analysis (PCA), and the results from the other two with traditional univariate methods. Measurements were made on breast cancer patients who had been exposed to different irradiation doses. A total of 28 breast cancer patients participated one to three times each; 12 were treated with photons at 4 or 6MeV and 16 were treated with high-energy electrons between 10 and 20 MeV to a maximum dose of 50 Gy. PCA of NIR spectra shows that information on radiation dose lies mainly in the first principal component. It is observed that the higher the dose the higher the score value. The results from the laser Doppler measurements show that in 79% of the cases the perfusion increases significantly with radiation dose. Analysis of the digital photography shows that a proposed skin redness index(SRI), increases with a higher radiation dose. However,the increase in most cases is not significant. By combining all data, correlation to radiation doses was seen for 74% of the patients who participated more than once. All three non-invasive methods correlate with the radiation dose but to various degrees. NIR spectroscopy, laser Doppler and a combination of the three techniques are the most promising methods for characterising erythema.

  4. Lattices for antiproton rings

    International Nuclear Information System (INIS)

    Autin, B.

    1984-01-01

    After a description of the constraints imposed by the cooling of Antiprotons on the lattice of the rings, the reasons which motivate the shape and the structure of these machines are surveyed. Linear and non-linear beam optics properties are treated with a special amplification to the Antiproton Accumulator. (orig.)

  5. LEAR: antiproton extraction lines

    CERN Multimedia

    Photographic Service

    1992-01-01

    Antiprotons, decelerated in LEAR to a momentum of 100 MeV/c (kinetic energy of 5.3 MeV), were delivered to the experiments in an "Ultra-Slow Extraction", dispensing some 1E9 antiprotons over times counted in hours. Beam-splitters and a multitude of beam-lines allowed several users to be supplied simultaneously.

  6. An apparatus for the measurement of antiproton-proton cross sections at low momenta

    International Nuclear Information System (INIS)

    Brueckner, W.; Doebbeling, H.; Guettner, F.; Kneis, H.; Paul, S.; Povh, B.; Ransome, R.D.; Treichel, M.; Walcher, T.; Majewski, S.; Nomachi, M.; Shibata, T.A.

    1988-01-01

    An experiment which aims at a precise measurement of anti pp cross sections at low momenta is presented. Its design and performance are described with emphasis on the particle identification capabilities. A calorimeter-like detector array which serves for the detection of antineutrons is discussed in some detail. Its properties were measured in a test experiment and are compared to Monte Carlo calculations. (orig.)

  7. Antiproton Induced Fission and Fragmentation of Nuclei

    CERN Multimedia

    2002-01-01

    The annihilation of slow antiprotons with nuclei results in a large highly localized energy deposition primarily on the nuclear surface. \\\\ \\\\ The study of antiproton induced fission and fragmentation processes is expected to yield new information on special nuclear matter states, unexplored fission modes, multifragmentation of nuclei, and intranuclear cascades.\\\\ \\\\ In order to investigate the antiproton-nucleus interaction and the processes following the antiproton annihilation at the nucleus, we propose the following experiments: \\item A)~Measurement of several fragments from fission and from multifragmentation in coincidence with particle spectra, especially neutrons and kaons. \\item B)~Precise spectra of $\\pi$, K, n, p, d and t with time-of-flight techniques. \\item C)~Installation of the Berlin 4$\\pi$ neutron detector with a 4$\\pi$ Si detector placed inside for fragments and charged particles. This yields neutron multiplicity distributions and consequently distributions of thermal excitation energies and...

  8. Comparison of Optimized Single and Multifield Irradiation Plans of Antiproton, Proton and Carbon Ion Beams

    DEFF Research Database (Denmark)

    Bassler, Niels; Kantemiris, Ioannis; Karaiskos, Pantelis

    2010-01-01

    Antiprotons have been suggested as a possibly superior modality for radiotherapy, due to the energy released when antiprotons annihilate, which enhances the Bragg peak and introduces a high-LET component to the dose. However, concerns are expressed about the inferior lateral dose distribution...

  9. Beam position pickup for antiprotons to the ISR

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    The Antiproton Project, launched for proton-antiproton collisions in the SPS (SPS collider), had a side-line for p-pbar collisions in the ISR. A new transfer line, TT6, was constructed to transport antiprotons from the 26 GeV PS to the injection line TT1 of ISR ring 2. Antiprotons were a scarce commodity. For setting up the lines, beam diagnostic devices in the antiproton path had to work reliably and precisely with just a few low-intensity pilot pules: single bunches of about 2x10**9 antiprotons every few hours. Electrostatic pickup electrodes were used to measure beam position. They could be mounted for measurement in the horizontal plane, as in this picture, or at 90 deg, for the vertical plane.

  10. Measurement of the single top production cross section in proton-antiproton collisions at 1.96 TeV

    International Nuclear Information System (INIS)

    Tanasijczuk, Andres Jorge

    2010-01-01

    This thesis describes a search for singly produced top quarks via an electroweak vertex in head-on proton-antiproton collisions at a center of mass energy of √s = 1.96 TeV. The analysis uses a total of 2.3 fb -1 of data collected with the D0 detector at Fermilab, corresponding to two different run periods of the Tevatron collider. Two channels contribute to single top quark production at the Tevatron, the s-channel and the t-channel. In the s-channel, a virtual W boson is produced from the aniquilation of a quark and an antiquark and a top and a bottom quarks are produced from the W decay. The top quark decays almost exclusively into a W boson and a bottom quark. Final states are considered in which the W boson decays leptonically into an electron or a muon plus a neutrino. Thus, at the detector level, the final state characterizing the s-channel contains one lepton, missing energy accounting for the neutrino, and two jets from the two bottom quarks. In the t-channel, the final state has an additional jet coming from a light quark. Clearly, a precise reconstruction of the events requires a precise measurement of the energy of the jets. A multivariate technique, Bayesian neural networks, is used to extract the single top signal from the overwhelming background still left after event selection. A Bayesian likelihood probability is then computed to measure the single top cross section. Assuming the observed excess is due to single top events, the measured single top quark production cross section is σ(p(bar p) → tb + X, tqb + X) = 4.70 -0.93 +1.18 pb. The observed excess is associated with a p-value of (3.2 ± 2.3) x 10 -8 , assuming the background-only hypothesis. This p-value corresponds to an excess over background of 5.4 standard deviations for a Gaussian density. The p-value computed using the standard model signal cross section of 3.46 pb is (22.7 ± 0.6) x 10 -6 , corresponding to an expected significance of 4.08 standard deviations.

  11. Measurement of the single top production cross section in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanasijczuk, Andres Jorge [Univ. of Buenos Aires (Argentina)

    2010-03-25

    This thesis describes a search for singly produced top quarks via an electroweak vertex in head-on proton-antiproton collisions at a center of mass energy of √s = 1.96 TeV. The analysis uses a total of 2.3 fb-1 of data collected with the D0 detector at Fermilab, corresponding to two different run periods of the Tevatron collider. Two channels contribute to single top quark production at the Tevatron, the s-channel and the t-channel. In the s-channel, a virtual W boson is produced from the aniquilation of a quark and an antiquark and a top and a bottom quarks are produced from the W decay. The top quark decays almost exclusively into a W boson and a bottom quark. Final states are considered in which the W boson decays leptonically into an electron or a muon plus a neutrino. Thus, at the detector level, the final state characterizing the s-channel contains one lepton, missing energy accounting for the neutrino, and two jets from the two bottom quarks. In the t-channel, the final state has an additional jet coming from a light quark. Clearly, a precise reconstruction of the events requires a precise measurement of the energy of the jets. A multivariate technique, Bayesian neural networks, is used to extract the single top signal from the overwhelming background still left after event selection. A Bayesian likelihood probability is then computed to measure the single top cross section. Assuming the observed excess is due to single top events, the measured single top quark production cross section is σ(p$\\bar{p}$ → tb + X, tqb + X) = 4.70+1.18-0.93 pb. The observed excess is associated with a p-value of (3.2 ± 2.3) x 10-8, assuming the background-only hypothesis. This p-value corresponds to an excess over background of 5.4 standard deviations for a Gaussian density. The p-value computed using the standard model signal cross section of 3.46 pb is (22.7 ± 0.6) x 10-6, corresponding to an expected significance

  12. Measurement of Neutral B Meson Mixing in Electron-Muon Events in 1.8-TeV Proton - Anti-proton Collisions

    Energy Technology Data Exchange (ETDEWEB)

    Mitsushio, Hisafumi [Univ. of Tsukuba (Japan)

    1996-01-01

    The B0$\\bar{B}$0 mixing parameter, x, has been measured in eμ events in proton-antiproton collisions at a center of mass energy of 1800 GeV. The experiment has been performed at the Fermi National Accelerator Laboratory in the United States using the Tevatron accelerator. The data were collected with the Collider Detector at Fermilab (CDF) during the 1992-1993 Tevatron collider run. The corresponding integrated luminosity is 20 pb-1.

  13. Measurement of the dijet transverse thrust distribution in proton - anti-proton collisions

    Energy Technology Data Exchange (ETDEWEB)

    Sorin, Maria Veronica

    2003-01-01

    This dissertation presents the first measurement in a hadron collider of an event shape variable, the Dijet Transverse Thrust T$t\\atop{2}$ which is sensitive to the spatial jet distribution on the plane perpendicular to the colliding p$\\bar{p}$ beams. $t\\atop{2}$ is calculated with the two most energetic jets reconstructed with the k$\\perp$ algorithm, and it ranges from T$t\\atop{2}$ =1, for a pencil-like configuration, to T$t\\atop{2}$ =√2/2, for two equal energy jets at 90°. The measurement is based on 87.3 pb-1 of data collected with the D0 detector at the Fermilab Tevatron p$\\bar{p}$ Collider. The cross section is reported as a function of 1-T$t\\atop{2}$ and log (1-T$t\\atop{2}$), with enhances the high statistics T$t\\atop{2}$→1 region, and presented for four separate event energy ranges. The measurement is in good agreement with a fixed-order O(α$3\\atop{s}$) perturbative QCD prediction, except at high T$t\\atop{2}$, where resummation corrections are expected to be important, and below T$t\\atop{2}$≃√3/2, where the leading order diagrams contributing to T$t\\atop{2}$ are O(α$4\\atop{s}$). The data also show a very good level of agreement with a recent Next-to-Leading pQCD three jet generator which covers the full T$t\\atop{2}$ range, except for the T$t\\atop{2}$=1 point.

  14. Developement of proportional chamber detectors and simulations to measure charm hadrons in antiproton-proton annihilation

    International Nuclear Information System (INIS)

    Sokolov, A.

    2005-07-01

    The present thesis describes the results of the simulation and the design of the tracking system of the anti PANDA detector together with the study of the physics efficiency of the complete system. The central tracking system of the proposed anti PANDA at FAIR/Darmstadt was studied by Monte-Carlo simulations. From this a spatial resolution of 20 μm for the micro-vertex detector (MVD) resulted. A new, more realistic design of the MVD was established on the base of the simulation results, in order to reach a better balance between the physical and technical requirements. It was shown that a momentum resolution of 0.4% can be reached with the straw-tube tracker (SST). The chosen gas mixture of Ar+10% CO 2 combines the measured good spatial resolution of ∝120 μm with a drift time of less than 100 ns, which is necessary in order to process the high hit rates. With a straw-tube prototype it was shown that is is possible, to determine the z coordinate from the measurement od the signal charge on both ends of the tube. A resolution of 8.9 mm or of 0.6% of the tube length was reached. Basing on these measurements a new design of the SST without a stereo-angle between single layers was proposed. The study of the only very unprecisely known charmonium spectrum above the d anti d threshold is one of the most important aspects of the anti PANDA physics program. In order to check, whether the anti PANDA detector fulfils the physical requirements the reactions: anti pp→ψ(3770)toD anti D and anti pp→ψ(4040)→D *+ D *- were studied as benchmark processes. A resolution of the invariant mass of 10 and of 16 MeV/c were demonstrated for the ψ(3770) respectively the ψ(4040). It was furthermore shown that the necessary background suppression by the factor 10 10 is reached. The widths of the states D * sJ (2317) + and D sJ (2460) + can be measured with a precission of better than 100 keV because of the excellent beam quality of the HESR storage ring. The reconstruction

  15. Measurements of the Ratio Between Double and Single Ionization of Helium for Antiprotons

    CERN Multimedia

    2002-01-01

    The inclusive spectra of @p|0's and @h's associated with @*p annihilation at rest are measured. Peaks in these spectra can be identified either with so far not explicitly observed two mesonic final states such as @p|0@w, @p|0@h, @h@h or @p|0@g, or with production of exotic mesonlike states such as baryonium. The apparatus is also suitable for searching for baryonium through some of its particular decay channels. As a by-product we expect information on direct @g production in @*p annihilations at rest.\\\\ \\\\ The apparatus consists of two modular BGO spectrometers and one array of leadglas detectors. The BGO spectrometers are adjustable in angle relative to each other and to the leadglas matrix, thus allowing to cover an angular range from 9|0 to 180|0, corresponding to momenta of zero to more than 1~GeV/c. The apparatus is designed such as to utilize the full potential of LEAR.

  16. Measuring side effects after radiotherapy for pharynx cancer

    DEFF Research Database (Denmark)

    Jensen, Kenneth

    2007-01-01

    Data on side effects after radiotherapy is needed to establish the benefits and drawbacks of new treatments, but side effects are not quantified as easily as survival or local control. Side effects may be quantified using physical measures. Unfortunately, only few endpoints exist where a physical...... measure is obtainable, and the case of a patient-relevant measure is even rarer. Radiotherapy is often followed by complex symptoms not easily quantifiable by the observer. Quantitative patient reported side effects can be retrieved using validated questionnaires, but this kind of data is often difficult...... to interpret and the correlation with clinically observable or measurable changes not straightforward. The exploitation of the possibilities of highly conformal radiotherapy and multimodality treatment depends on a better understanding of the correlation between dose, volume, modifying factors, and side...

  17. Measurement of antiproton production in p-He collisions and prospects for other inputs to cosmic rays physics from the fixed target program of the LHCb experiment

    CERN Document Server

    Graziani, Giacomo

    2018-01-01

    The LHCb experiment has the unique possibility, among the LHC experiments, to be operated in fixed target mode, using its internal gas target SMOG. The energy scale achievable at the LHC and the excellent detector capabilities for vertexing, tracking and particle identification allow a wealth of measurements of great interest for cosmic ray physics. We present the first measurement of antiproton production in proton-helium collisions at $\\sqrt s_{NN} = 110$ GeV, which allows to improve the accuracy of the prediction for secondary antiproton production in cosmic rays. Prospects for other measurements achievable in the fixed target program are also discussed.

  18. Radiotherapy

    International Nuclear Information System (INIS)

    Prosnitz, L.R.; Kapp, D.S.; Weissberg, J.B.

    1983-01-01

    This review highlights developments over the past decade in radiotherapy and attempts to summarize the state of the art in the management of the major diseases in which radiotherapy has a meaningful role. The equipment, radiobiology of radiotherapy and carcinoma of the lung, breast and intestines are highlighted

  19. Calculated LET Spectrum from Antiproton Beams Stopping in Water

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    2009-01-01

    Antiprotons have been proposed as a potential modality for radiotherapy because the annihilation at the end of range leads to roughly a doubling of physical dose in the Bragg peak region. So far it has been anticipated that the radiobiology of antiproton beams is similar to that of protons...... in the entry region of the beam, but very different in the annihilation region, due to the expected high-LET components resulting from the annihilation. On closer inspection we find that calculations of dose averaged LET in the entry region may suggest that the RBE of antiprotons in the plateau region could...... antiproton beam we observe a dose-averaged unrestricted LET of about 4 keV/μm, which is very different from the expected 0.6 keV/μm of an equivalent primary proton beam. Even though the fluence of secondaries is a magnitude less than the fluence of primary particles, the increased stopping power...

  20. Proton-antiproton workshop

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Coming just two months after Fermilab announced definitive discovery of the sixth ('top') quark, the 10th proton-antiproton workshop, held at Fermilab from 9-13 May, provided a useful overview of this important physics sector. With the sixth quark in place, the conference opened with an eye to the exotic, beginning with searches at the Tevatron for phenomena beyond the Standard Model. Experimenters from CDF and DO showed the latest lower bounds on masses for leptoquarks, new heavy gauge bosons, gluinos, squarks and other aspiring particles. Limits were raised, and new areas explored, but nothing new seemed to be stirring. Theorists, like expectant parents, showed their latest predictions for where particles would appear and how they would behave, but at the end, the Standard Model was still standing defiantly on its own two feet. The focus then turned to fifth ('bottom', b) and fourth ('charm') quark production, where, ironically, theory and experiment showed some disagreement. Both CDF and DO presented results for b quark production which agreed with each other but remained higher than theoretical predictions (perturbative quantum chromodynamics, QCD, using nextto- leading-order). On the charm front, the prompt production of psi-prime particles was shown to be anomalously high, many times higher than theoretical predictions. Latest results for the lifetimes of B particles (containing the bquark), quarkonia production and neutral B mixing were also presented. Closing the session, Jonathan Rosner of Chicago gave a theoretical overview of B physics at the Tevatron, and presented prospects for measuring the violation of CP (matter-antimatter) symmetry in the b sector. For the top quark, neither CDF's nor DO's results had much changed since their 2 March discovery announcement (April, page 1). Interesting discussions centred on the differences between the two experiments' methods of measuring the top mass. Clearly the

  1. Antiproton production for Tevatron

    International Nuclear Information System (INIS)

    Azhgirey, I.L.; Mokhov, N.V.; Striganov, S.I.

    1991-03-01

    Needs to improve the Fermilab Pbar Source for the Tevatron Upgrade and discrepancies in predictions of the antiproton yields have forced us to develop the production model based on the modern data and to incorporate this model to the current version of MARS10 code. The inclusive scheme of this code with the use of statistical weights allows the production of antiprotons to be enhanced within the phase space region of interest, which is extremely effective for optimization of Pbar Source parameters and for developing of such an idea as a beam sweeping system. Antiproton production model included in the modified version of our Monte Carlo program MARS10M for the inclusive simulation of hadronic cascades, as for other particles throughout the program, is based on a factorization approach for hadron-nucleus differential cross-section. To describe antiproton inclusive spectra in pp-collisions a phenomenological model has been used modified in the low-Pt region. The antiproton production in pion-nucleon interactions is described in the frame of our simple phenomenological model based on the modern data. In describing of the of antiproton production cross-sections ratio in hadron-nucleus and hadron-nucleon collisions the ideas of soft hadronization of color strings and all the present experimental data have been used. Some comparisons of our model with experimental data are presented in the wide intervals of initial momenta, antiproton kinematical variables and nuclei. In all the cases the agreement is pretty good what gives us an assurance in the consequent studies carried out for the Fermilab Pbar Source. The results of such study are presented in this paper

  2. Spectroscopy of antiprotonic helium atoms and its contribution to the fundamental physical constants.

    Science.gov (United States)

    Hayano, Ryugo S

    2010-01-01

    Antiprotonic helium atom, a metastable neutral system consisting of an antiproton, an electron and a helium nucleus, was serendipitously discovered, and has been studied at CERN's antiproton decelerator facility. Its transition frequencies have recently been measured to nine digits of precision by laser spectroscopy. By comparing these experimental results with three-body QED calculations, the antiproton-to-electron massratio was determined as 1836.152674(5). This result contributed to the CODATA recommended values of the fundamental physical constants

  3. Radiotherapy

    Directory of Open Access Journals (Sweden)

    Rema Jyothirmayi

    1999-01-01

    Full Text Available Purpose. Conservative treatment in the form of limited surgery and post-operative radiotherapy is controversial in hand and foot sarcomas, both due to poor radiation tolerance of the palm and sole, and due to technical difficulties in achieving adequate margins.This paper describes the local control and survival of 41 patients with soft tissue sarcoma of the hand or foot treated with conservative surgery and radiotherapy. The acute and late toxicity of megavoltage radiotherapy to the hand and foot are described. The technical issues and details of treatment delivery are discussed. The factors influencing local control after radiotherapy are analysed.

  4. The Antiproton-Nucleon Annihilation Process (Antiproton Collaboration Experiment)

    Science.gov (United States)

    Barkas, W. H.; Birge, R. W.; Chupp, W. W.; Ekspong, A. G.; Goldhaber, G.; Goldhaber, S.; Heckman, H. H.; Perkins, D. H.; Sandweiss, J.; Segre, E.; Smith, F. M.; Stork, D. H.; Rossum, L. Van; Amaldi, E.; Baroni, G.; Castagnoli, C.; Franzinetti, C.; Manfredini, A.

    1956-09-10

    In the exposure to a 700-MeV/c negative particle beam, 35 antiproton stars have been found. Of these antiprotons, 21 annihilate in flight and three give large-angle scatters ({Theta} > 15 , T{sub P-} > 50 Mev), while 14 annihilate at rest. From the interactions in flight we obtain the total cross section for antiproton interaction.

  5. An Update on the Depth-Dose Curve of Antiprotons

    DEFF Research Database (Denmark)

    Taasti, Vicki Trier; Holzscheiter, Michael H.; Knudsen, Helge

    Purpose: The CERN AD-4/ACE project aims to measure the relative biological effectiveness of antiprotons. We have revisited previously published data for the antiproton depth-dose curve [1], where the relative dose deposition normalized to a point in the plateau region was plotted. In this revisio...

  6. FERMILAB: More antiprotons

    International Nuclear Information System (INIS)

    Visnjic, Vladimir

    1993-01-01

    The excellent performance of the Fermilab antiproton complex during the recent Collider run and its future potential are the cumulative result of many improvements over the past few years, ranging from major projects like upgrading the stack-tail stochastic cooling system in the Accumulator to minor improvements like automating tuning procedures. The antiprotons are created when the 120 GeV proton beam from the Main Ring hits the target. A good target should have high yield of antiprotons, should not melt, and should not crack due to shock waves. The old copper target has been replaced by a new one made of nickel. The yield into the Debuncher is 2 x 10 -5 antiprotons/proton. While this is only marginally better than for copper, the nickel target has high melting point energy (1070 J/g) and a low rate of increase in pressure with deposited energy, making it the target of choice for the proton intensities expected in the Main Injector era (June, page 10). Of the broad spectrum of all kinds of secondaries, only a tiny fraction are 8 GeV antiprotons. The 8 GeV negative charge secondaries are bent through 3° by a new pulsed magnet. Instead of a 200-turn magnet with coils separated by epoxy as in the past, the new magnet has one turn carrying 45.5 kA of current. This single turn pulsed magnet uses radiation hard ceramic and is much more robust

  7. Interaction of antiprotons with nuclei

    Czech Academy of Sciences Publication Activity Database

    Hrtánková, Jaroslava; Mareš, Jiří

    2016-01-01

    Roč. 945, JAN (2016), s. 197-215 ISSN 0375-9474 R&D Projects: GA ČR(CZ) GA15-04301S Institutional support: RVO:61389005 Keywords : antiproton-nucleus interaction * antiproton annihilation * antiproton nuclear bound states Subject RIV: BE - Theoretical Physics Impact factor: 1.916, year: 2016

  8. Antiproton distributions in Au+nucleus collisions

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D.; Debbe, R. [Brookhaven National Laboratory, Upton, New York (United States); Bennett, M.J.; Chikanian, A.; Kumar, B.S.; Nagle, J.L.; Pope, J.K. [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, Connecticut (United States); Carroll, J.B.; Hallman, T.J. [University of California at Los Angeles, Los Angeles, California (United States); Chiba, J.; Tanaka, K.H. [National Laboratory for High Energy Physics (KEK), Tsukuba (Japan); Crawford, H.J.; Cronqvist, M.; Dardenne, Y.; Engelage, J.; Greiner, L.; Kuo, C. [University of California Space Sciences Laboratory, Berkeley, California (United States); Doke, T.; Kashiwagi, T.; Kikuchi, J. [Waseda University, Tokyo (Japan); Hayano, R.S. [University of Tokyo, Tokyo (Japan); Heckman, H.H.; Lindstrom, P.J. [Lawrence Berkeley Laboratory, Berkeley, California (United States); Mitchell, J.W. [Universities Space Sciences Research Association/Goddard Space Flight Center, Greenbelt, Maryland (United States); Nagamiya, S.; Stankus, P.; Zhan, W. [Nevis Laboratory, Columbia University, Irvington, New York (United States); Welsh, R.C. [Johns Hopkins University, Baltimore, Maryland (United States)

    1997-09-01

    Experiment E878 at the BNL-AGS has measured the invariant cross sections of antiprotons produced near p{sub t}=0 in interactions of 10.8 GeV/c Au beams with targets of Al, Cu, and Au. The data were measured for a wide range of centralities and rapidities using a focusing beamline spectrometer and a high-rate centrality detector. We compare our data with the predictions of simple models and sophisticated transport models to explore the physics of antiproton production and annihilation. {copyright} {ital 1997} {ital The American Physical Society}

  9. Radiotherapy

    International Nuclear Information System (INIS)

    Zedgenidze, G.A.; Kulikov, V.A.; Mardynskij, Yu.S.

    1984-01-01

    The technique for roentgenotopometric and medicamentous preparation of patients for radiotherapy has been reported in detail. The features of planning and performing of remote, intracavitary and combined therapy in urinary bladder cancer are considered. The more effective methods of radiotherapy have been proposed taking into account own experience as well as literature data. The comparative evaluation of treatment results and prognosis are given. Radiation pathomorphism of tumors and tissues of urinary bladder is considered in detail. The problems of diagnosis, prophylaxis and treatment of complications following radiodiagnosis and radiotherapy in patients with urinary bladder cancer are illustrated widely

  10. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer.

    Science.gov (United States)

    Maglieri, Robert; Licea, Angel; Evans, Michael; Seuntjens, Jan; Kildea, John

    2015-11-01

    Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation-maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors' measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. The NNS may be used to reliably measure the neutron

  11. Measuring neutron spectra in radiotherapy using the nested neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Maglieri, Robert, E-mail: robert.maglieri@mail.mcgill.ca; Evans, Michael; Seuntjens, Jan; Kildea, John [Medical Physics Unit, McGill University, Montreal, Quebec H4A 3J1 (Canada); Licea, Angel [Canadian Nuclear Safety Commission, Ottawa, Ontario K1P 5S9 (Canada)

    2015-11-15

    Purpose: Out-of-field neutron doses resulting from photonuclear interactions in the head of a linear accelerator pose an iatrogenic risk to patients and an occupational risk to personnel during radiotherapy. To quantify neutron production, in-room measurements have traditionally been carried out using Bonner sphere systems (BSS) with activation foils and TLDs. In this work, a recently developed active detector, the nested neutron spectrometer (NNS), was tested in radiotherapy bunkers. Methods: The NNS is designed for easy handling and is more practical than the traditional BSS. Operated in current-mode, the problem of pulse pileup due to high dose-rates is overcome by measuring current, similar to an ionization chamber. In a bunker housing a Varian Clinac 21EX, the performance of the NNS was evaluated in terms of reproducibility, linearity, and dose-rate effects. Using a custom maximum-likelihood expectation–maximization algorithm, measured neutron spectra at various locations inside the bunker were then compared to Monte Carlo simulations of an identical setup. In terms of dose, neutron ambient dose equivalents were calculated from the measured spectra and compared to bubble detector neutron dose equivalent measurements. Results: The NNS-measured spectra for neutrons at various locations in a treatment room were found to be consistent with expectations for both relative shape and absolute magnitude. Neutron fluence-rate decreased with distance from the source and the shape of the spectrum changed from a dominant fast neutron peak near the Linac head to a dominant thermal neutron peak in the moderating conditions of the maze. Monte Carlo data and NNS-measured spectra agreed within 30% at all locations except in the maze where the deviation was a maximum of 40%. Neutron ambient dose equivalents calculated from the authors’ measured spectra were consistent (one standard deviation) with bubble detector measurements in the treatment room. Conclusions: The NNS may

  12. On the antiproton discovery

    International Nuclear Information System (INIS)

    Piccioni, O.

    1989-01-01

    The author of this article describes his own role in the discovery of the antiproton. Although Segre and Chamberlain received the Nobel Prize in 1959 for its discovery, the author claims that their experimental method was his idea which he communicated to them informally in December 1954. He describes how his application for citizenship (he was Italian), and other scientists' manipulation, prevented him from being at Berkeley to work on the experiment himself. (UK)

  13. Bubble chamber: antiproton annihilation

    CERN Multimedia

    1971-01-01

    These images show real particle tracks from the annihilation of an antiproton in the 80 cm Saclay liquid hydrogen bubble chamber. A negative kaon and a neutral kaon are produced in this process, as well as a positive pion. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that had been heated to boiling point.

  14. Calculated LET spectrum from antiproton beams stopping in water

    CERN Document Server

    Bassler, Niels

    2009-01-01

    Antiprotons have been proposed as a potential modality for radiotherapy because the annihilation at the end of range leads to roughly a doubling of physical dose in the Bragg peak region. So far it has been anticipated that the radiobiology of antiproton beams is similar to that of protons in the entry region of the beam, but very different in the annihilation region, due to the expected high-LET components resulting from the annihilation. On closer inspection we find that calculations of dose averaged LET in the entry region may suggest that the RBE of antiprotons in the plateau region could significantly differ from unity, which seems to warrant closer inspection of the radiobiology in this region. Materials and Methods. Monte Carlo simulations using FLUKA were performed for calculating the entire particle spectrum of a beam of 126 MeV antiprotons hitting a water phantom. Results and Discussion. In the plateau region of the simulated antiproton beam we observe a dose-averaged unrestrict...

  15. ALPHA freezes antiprotons

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Laboratories like CERN can routinely produce many different types of antiparticles. In 1995, the PS210 experiment formed the first antihydrogen atoms and a few years later, in 2002, ATRAP and ATHENA were already able to produce several thousand of them. However, no experiment in the world has succeeded in ‘trapping’ these anti-atoms in order to study them. This is the goal of the ALPHA experiment, which has recently managed to cool down the antiprotons to just a few Kelvin. This represents a major step towards trapping the anti-atom, thus opening a new avenue into the investigation of antimatter properties.   Members of the ALPHA collaboration working on the apparatus in the Antiproton Decelerator experimental hall at CERN. Just like the atom, the anti-atom is neutral. Unlike the atom, the anti-atom is made up of antiprotons (as opposed to protons in the atom) and positrons (as opposed to electrons). In order to thoroughly study the properties of the anti-atoms, scien...

  16. Extra Low ENergy Antiproton

    CERN Multimedia

    To produce dense antiproton beams at very low energies (110 keV), it has been proposed to install a small decelerator ring between the existing AD ring and the experimental area. Phase-space blowup during deceleration is compensated by electron cooling such that the final emittances are comparable to the 5MeV beam presently delivered by the AD. An immediate consequence is a significant increase in the number of trapped antiprotons at the experiments as outlined in the proposal CERN/SPSC-2009-026; SPCS-P-338. This report describes the machine parameters and layout of the proposal ELENA (Extra Low ENergy Antiproton)ring also gives an approximate estimate of cost and manpower needs. Since the initial estimate, published in 2007 (CERN-AB-2007-079), the ELENA design has evolved considerably. This is due to a new location in the AD hall to acommodate for the possibility of another experimental zone, as suggested by the SPCS, and also due to improvements in the ring optics and layout. The cost estimate that is prese...

  17. CERN Antiproton Decelerator Beam Instrumentation for the ELENA era

    CERN Document Server

    Ludwig, M; Gasior, M; Søby, L; Tranquille, G; Fernandes, M

    2014-01-01

    CERN is currently constructing an Extra Low ENergy Antiproton ring (ELENA), which will allow the further deceleration of antiprotons from the currently exploited Antiproton Decelerator (AD). In order to meet the challenges of ELENA the beam instrumentation systems of the CERN AD are being consolidated and upgraded. An updated controls architecture with a more flexible timing system needs to be adopted and obsolete systems must be replaced. This paper presents the status and plans for improved performance and measurement availability of the AD beam instrumentation with a decreased risk of failure.

  18. Midrapidity antiproton-to-proton ratio in pp collisions at $\\sqrt{s} = 0.9$ and $7$~TeV measured by the ALICE experiment

    CERN Document Server

    Aamodt, K.; Abeysekara, U.; Abrahantes Quintana, A.; Abramyan, A.; Adamova, 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.; Almaraz Avina, E.; Alme, J.; Alt, T.; Altini, V.; Altinpinar, S.; Andrei, C.; Andronic, A.; Anelli, G.; Angelov, V.; Anson, C.; Anticic, T.; Antinori, F.; Antinori, S.; Antipin, K.; Antonczyk, D.; Antonioli, P.; Anzo, A.; Aphecetche, L.; Appelshauser, 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.; Aysto, J.; Azmi, M.D.; Bablok, S.; Bach, M.; Badala, A.; Baek, Y.W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Baldit, A.; Ban, J.; Barbera, R.; Barnafoldi, 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.; Bielcik, J.; Bielcikova, J.; Bilandzic, A.; Bimbot, L.; Biolcati, E.; Blanc, A.; Blanco, F.; Blau, D.; Blume, C.; Boccioli, M.; Bock, N.; Bogdanov, A.; Boggild, H.; Bogolyubsky, M.; Bohm, J.; Boldizsar, L.; Bombara, M.; Bombonati, C.; Bondila, M.; Borel, H.; Borisov, A.; Bortolin, C.; Bose, S.; Bosisio, L.; Bossu, F.; Botje, M.; Bottger, 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.; 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 Diaz, 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.; 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.; Cortes 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.; 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 Marco, N.; De Pasquale, S.; De Remigis, R.; de Rooij, R.; de Vaux, G.; Delagrange, H.; Dellacasa, G.; Deloff, A.; Demanov, V.; Denes, 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.; Diaz, L.; Diaz, R.; Dietel, T.; Divia, R.; Djuvsland, O.; Dobretsov, V.; Dobrin, A.; Dobrowolski, T.; Donigus, B.; Dominguez, I.; 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.; Esumi, S.; Evans, D.; Evrard, S.; Eyyubova, G.; Fabjan, C.W.; Fabris, D.; Faivre, J.; Falchieri, D.; Fantoni, A.; Fasel, M.; Fateev, O.; Fearick, R.; Fedunov, A.; Fehlker, D.; Fekete, V.; Felea, D.; Fenton-Olsen, B.; Feofilov, G.; Fernandez Tellez, 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.; Gaardhoje, J.J.; Gadrat, S.; Gagliardi, M.; Gago, A.; Gallio, M.; Ganoti, P.; Ganti, M.S.; Garabatos, C.; Garcia Trapaga, C.; Gebelein, J.; Gemme, R.; Germain, M.; Gheata, A.; Gheata, M.; Ghidini, B.; Ghosh, P.; Giraudo, G.; Giubellino, P.; Gladysz-Dziadus, E.; Glasow, R.; Glassel, P.; Glenn, A.; Gomez Jimenez, R.; Gonzalez Santos, H.; Gonzalez-Trueba, L.H.; Gonzalez-Zamora, P.; Gorbunov, S.; Gorbunov, Y.; Gotovac, S.; Gottschlag, H.; Grabski, V.; Grajcarek, R.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Gros, P.; Grosse-Oetringhaus, J.F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gulkanyan, H.; Gunji, T.; Gupta, A.; Gupta, R.; Gustafsson, H.-A.; Gutbrod, H.; Haaland, O.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hamblen, J.; Han, B.H.; Harris, J.W.; Hartig, M.; Harutyunyan, A.; Hasch, D.; Hasegan, D.; Hatzifotiadou, D.; Hayrapetyan, A.; Heide, M.; Heinz, M.; Helstrup, H.; Herghelegiu, A.; Hernandez, C.; Herrera Corral, G.; Herrmann, N.; Hetland, K.F.; Hicks, B.; Hiei, A.; Hille, P.T.; Hippolyte, B.; Horaguchi, T.; Hori, Y.; Hristov, P.; Hrivnacova, I.; Hu, S.; Huang, M.; Huber, S.; Humanic, T.J.; Hutter, D.; Hwang, D.S.; Ichou, R.; Ilkaev, R.; Ilkiv, I.; Inaba, M.; Innocenti, P.G.; Ippolitov, M.; Irfan, M.; Ivan, C.; Ivanov, A.; Ivanov, M.; Ivanov, V.; Iwasaki, T.; Jacholkowski, A.; Jacobs, P.; Jancurova, L.; Jangal, S.; Janik, R.; Jena, C.; Jena, S.; Jirden, L.; Jones, G.T.; Jones, P.G.; Jovanovic, P.; Jung, H.; Jung, W.; Jusko, A.; Kaidalov, A.B.; Kalcher, S.; Kalinak, P.; Kalisky, M.; Kalliokoski, T.; Kalweit, A.; Kamal, A.; Kamermans, R.; Kanaki, K.; Kang, E.; Kang, J.H.; Kapitan, J.; Kaplin, V.; Kapusta, S.; Karavichev, O.; Karavicheva, T.; Karpechev, E.; Kazantsev, A.; Kebschull, U.; Keidel, R.; Khan, M.M.; Khan, S.A.; Khanzadeev, A.; Kharlov, Y.; Kikola, D.; Kileng, B.; Kim, D.J; Kim, D.S.; Kim, D.W.; Kim, H.N.; Kim, J.; Kim, J.H.; Kim, J.S.; Kim, M.; Kim, S.H.; Kim, S.; Kim, Y.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Klay, J.L.; Klein, J.; Klein-Bosing, C.; Kliemant, M.; Klovning, A.; Kluge, A.; Knichel, M.L.; Kniege, S.; Koch, K.; Kolevatov, R.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Konevskih, A.; Kornas, E.; Kour, R.; Kowalski, M.; Kox, S.; Kozlov, K.; Kral, J.; Kralik, I.; Kramer, F.; Kraus, I.; Kravcakova, A.; Krawutschke, T.; Krivda, M.; Krumbhorn, D.; Krus, M.; Kryshen, E.; Krzewicki, M.; Kucheriaev, Y.; Kuhn, C.; Kuijer, P.G.; Kumar, L.; Kumar, N.; Kupczak, R.; Kurashvili, P.; Kurepin, A.; Kurepin, A.N.; Kuryakin, A.; Kushpil, S.; Kushpil, V.; Kutouski, M.; Kvaerno, H.; Kweon, M.J.; Kwon, Y.; La Rocca, P.; Lackner, F.; Ladron de Guevara, P.; Lafage, V.; Lal, C.; Lara, Camilo; Larsen, D.T.; Laurenti, G.; Lazzeroni, C.; Le Bornec, Y.; Le Bris, N.; Lee, H.; Lee, K.S.; Lee, S.C.; Lefevre, F.; Lenhardt, M.; Leistam, L.; Lehnert, J.; Lenti, V.; Leon, H.; Leon Monzon, I.; Leon Vargas, H.; Levai, P.; Li, X.; Li, Y.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M.A.; Liu, L.; Loginov, V.; Lohn, S.; Lopez, X.; Lopez Noriega, M.; Lopez-Ramirez, R.; Lopez Torres, E.; Lovhoiden, G.; Lozea Feijo Soares, A.; Lu, S.; Lunardon, M.; Luparello, G.; Luquin, L.; Lutz, J.-R.; Ma, K.; Ma, R.; Madagodahettige-Don, D.M.; Maevskaya, A.; Mager, M.; Mahapatra, D.P.; Maire, A.; Makhlyueva, I.; Mal'Kevich, D.; Malaev, M.; Malagalage, K.J.; Maldonado Cervantes, I.; Malek, M.; Malkiewicz, T.; Malzacher, P.; Mamonov, A.; Manceau, L.; Mangotra, L.; Manko, V.; Manso, F.; Manzari, V.; Mao, Y.; Mares, J.; Margagliotti, G.V.; Margotti, A.; Marin, A.; Martashvili, I.; Martinengo, P.; Martinez Hernandez, M.I.; Martinez Davalos, A.; Martinez Garcia, G.; Maruyama, Y.; Marzari Chiesa, A.; Masciocchi, S.; Masera, M.; Masetti, M.; Masoni, A.; Massacrier, L.; Mastromarco, M.; Mastroserio, A.; Matthews, Z.L.; Matyja, A.; Mayani, D.; Mazza, G.; Mazzoni, M.A.; Meddi, F.; Menchaca-Rocha, A.; Mendez Lorenzo, P.; Meoni, M.; Mercado Perez, J.; Mereu, P.; Miake, Y.; Michalon, A.; Miftakhov, N.; Milano, L.; Milosevic, J.; Minafra, F.; Mischke, A.; Miskowiec, D.; Mitu, C.; Mizoguchi, K.; Mlynarz, J.; Mohanty, B.; Molnar, L.; Mondal, M.M.; Montano Zetina, L.; Monteno, M.; Montes, E.; Morando, M.; Moretto, S.; Morsch, A.; Moukhanova, T.; Muccifora, V.; Mudnic, E.; Muhuri, S.; Muller, H.; Munhoz, M.G.; Munoz, J.; Musa, L.; Musso, A.; Nandi, B.K.; Nania, R.; Nappi, E.; Navach, F.; Navin, S.; Nayak, T.K.; Nazarenko, S.; Nazarov, G.; Nedosekin, A.; Nendaz, F.; Newby, J.; Nianine, A.; Nicassio, M.; Nielsen, B.S.; Nikolaev, S.; Nikolic, V.; Nikulin, S.; Nikulin, V.; Nilsen, B.S.; Nilsson, M.S.; Noferini, F.; Nomokonov, P.; Nooren, G.; Novitzky, N.; Nyatha, A.; Nygaard, C.; Nyiri, A.; Nystrand, J.; Ochirov, A.; Odyniec, G.; Oeschler, H.; Oinonen, M.; Okada, K.; Okada, Y.; Oldenburg, M.; Oleniacz, J.; Oppedisano, C.; Orsini, F.; Ortiz Velasquez, A.; Ortona, G.; Oskarsson, A.; Osmic, F.; Osterman, L.; Ostrowski, P.; Otterlund, I.; Otwinowski, J.; Ovrebekk, G.; Oyama, K.; Ozawa, K.; Pachmayer, Y.; Pachr, M.; Padilla, F.; Pagano, P.; Paic, G.; Painke, F.; Pajares, C.; Pal, S.; Pal, S.K.; Palaha, A.; Palmeri, A.; Panse, R.; Papikyan, V.; Pappalardo, G.S.; Park, W.J.; Pastircak, B.; Pastore, C.; Paticchio, V.; Pavlinov, A.; Pawlak, T.; Peitzmann, T.; Pepato, A.; Pereira, H.; Peressounko, D.; Perez, C.; Perini, D.; Perrino, D.; Peryt, W.; Peschek, J.; Pesci, A.; Peskov, V.; Pestov, Y.; Peters, A.J.; Petracek, V.; Petridis, A.; Petris, M.; Petrov, P.; Petrovici, M.; Petta, C.; Peyre, J.; Piano, S.; Piccotti, A.; Pikna, M.; Pillot, P.; Pinazza, O.; Pinsky, L.; Pitz, N.; Piuz, F.; Platt, R.; Ploskon, M.; Pluta, J.; Pocheptsov, T.; Pochybova, S.; Podesta Lerma, P.L.M.; Poggio, F.; Poghosyan, M.G.; Polak, K.; Polichtchouk, B.; Polozov, P.; Polyakov, V.; Pommeresch, B.; Pop, A.; Posa, F.; Pospisil, V.; Potukuchi, B.; Pouthas, J.; Prasad, S.K.; Preghenella, R.; Prino, F.; Pruneau, C.A.; Pshenichnov, I.; Puddu, G.; Pujahari, P.; Pulvirenti, A.; Punin, A.; Punin, V.; Putis, M.; Putschke, J.; Quercigh, E.; Rachevski, A.; Rademakers, A.; Radomski, S.; Raiha, T.S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rodriguez Cahuantzi, M.; Rammler, M.; Raniwala, R.; Raniwala, S.; Rasanen, S.S.; Rashevskaya, I.; Rath, S.; Read, K.F.; Real, J.S.; Redlich, K.; Renfordt, R.; Reolon, A.R.; Reshetin, A.; Rettig, F.; Revol, J.-P.; Reygers, K.; Ricaud, H.; Riccati, L.; Ricci, R.A.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Rivetti, A.; Roed, K.; Rohrich, D.; Roman Lopez, S.; Romita, R.; Ronchetti, F.; Rosinsky, P.; Rosnet, P.; Rossegger, S.; Rossi, A.; Roukoutakis, F.; Rousseau, S.; Roy, C.; Roy, P.; Rubio-Montero, A.J.; Rui, R.; Rusanov, I.; Russo, G.; Ryabinkin, E.; Rybicki, A.; Sadovsky, S.; Safarik, K.; Sahoo, R.; Saini, J.; Saiz, P.; Sakata, D.; Salgado, C.A.; Salgueiro Domingues da Silva, R.; Salur, S.; Samanta, T.; Sambyal, S.; Samsonov, V.; Sandor, L.; Sandoval, A.; Sano, M.; Sano, S.; Santo, R.; Santoro, R.; Sarkamo, J.; Saturnini, P.; Scapparone, E.; Scarlassara, F.; Scharenberg, R.P.; Schiaua, C.; Schicker, R.; Schindler, H.; Schmidt, C.; Schmidt, H.R.; Schossmaier, K.; Schreiner, S.; Schuchmann, S.; Schukraft, J.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, P.A.; Segato, G.; Semenov, D.; Senyukov, S.; Seo, J.; Serci, S.; Serkin, L.; Serradilla, E.; Sevcenco, A.; Sgura, I.; Shabratova, G.; Shahoyan, R.; Sharkov, G.; Sharma, N.; Sharma, S.; Shigaki, K.; Shimomura, M.; Shtejer, K.; Sibiriak, Y.; Siciliano, M.; Sicking, E.; Siddi, E.; Siemiarczuk, T.; Silenzi, A.; Silvermyr, D.; Simili, E.; Simonetti, G.; Singaraju, R.; Singh, R.; Singhal, V.; Sinha, B.C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T.B.; Skjerdal, K.; Smakal, R.; Smirnov, N.; Snellings, R.; Snow, H.; Sogaard, C.; Soloviev, A.; Soltveit, H.K.; Soltz, R.; Sommer, W.; Son, C.W.; Son, Hyungsuk; Song, M.; Soos, C.; Soramel, F.; Soyk, D.; Spyropoulou-Stassinaki, M.; Srivastava, B.K.; Stachel, J.; Staley, F.; Stan, E.; Stefanek, G.; Stefanini, G.; Steinbeck, T.; Stenlund, E.; Steyn, G.; Stocco, D.; Stock, R.; Stolpovsky, P.; Strmen, P.; Suaide, A.A.P.; Subieta Vasquez, M.A.; Sugitate, T.; Suire, C.; Sumbera, M.; Susa, T.; Swoboda, D.; Symons, J.; Szanto de Toledo, A.; Szarka, I.; Szostak, A.; Szuba, M.; Tadel, M.; Tagridis, C.; Takahara, A.; Takahashi, J.; Tanabe, R.; Tapia Takaki, J.D.; Taureg, H.; Tauro, A.; Tavlet, M.; Tejeda Munoz, G.; Telesca, A.; Terrevoli, C.; Thaeder, Jochen Mathias; Tieulent, R.; Tlusty, D.; Toia, A.; Tolyhy, T.; Torcato de Matos, C.; Torii, H.; Torralba, G.; Toscano, L.; Tosello, F.; Tournaire, A.; Traczyk, T.; Tribedy, P.; Troger, G.; Truesdale, D.; Trzaska, W.H.; Tsiledakis, G.; Tsilis, E.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Turvey, A.; Tveter, T.S.; Tydesjo, H.; Tywoniuk, K.; Ulery, J.; Ullaland, K.; Uras, A.; Urban, J.; Urciuoli, G.M.; Usai, G.L.; Vacchi, A.; Vala, M.; Valencia Palomo, L.; Vallero, S.; van der Kolk, N.; Vyvre, P.Vande; van Leeuwen, M.; Vannucci, L.; Vargas, A.; Varma, R.; Vasiliev, A.; Vassiliev, I.; Vasileiou, M.; Vechernin, V.; Venaruzzo, M.; Vercellin, E.; Vergara, S.; Vernet, R.; Verweij, M.; Vetlitskiy, I.; Vickovic, L.; Viesti, G.; Vikhlyantsev, O.; Vilakazi, Z.; Villalobos Baillie, O.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Viyogi, Y.P.; Vodopianov, A.; Voloshin, K.; Voloshin, S.; Volpe, G.; von Haller, B.; Vranic, D.; Vrlakova, J.; Vulpescu, B.; Wagner, B.; Wagner, V.; Wallet, L.; Wan, R.; Wang, D.; Wang, Y.; Watanabe, K.; Wen, Q.; Wessels, J.; Westerhoff, U.; Wiechula, J.; Wikne, J.; Wilk, A.; Wilk, G.; Williams, M.C.S.; Willis, N.; Windelband, B.; Xu, C.; Yang, C.; Yang, H.; Yasnopolskiy, S.; Yermia, F.; Yi, J.; Yin, Z.; Yokoyama, H.; Yoo, I-K.; Yuan, X.; Yurevich, V.; Yushmanov, I.; Zabrodin, E.; Zagreev, B.; Zalite, A.; Zampolli, C.; Zanevsky, Yu.; Zaporozhets, S.; Zarochentsev, A.; Zavada, P.; Zbroszczyk, H.; Zelnicek, P.; Zenin, A.; Zepeda, A.; Zgura, I.; Zhalov, M.; Zhang, X.; Zhou, D.; Zhou, S.; Zhu, J.; Zichichi, A.; Zinchenko, A.; Zinovjev, G.; Zoccarato, Y.; Zychacek, V.; Zynovyev, M.

    2010-01-01

    The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at $\\sqrt{s} = 0.9$ and $7$~TeV during the initial running periods of the Large Hadron Collider(LHC). The measurement covers the transverse momentum interval $0.45 < p_{\\rm{t}} < 1.05$~GeV/$c$ and rapidity $|y| < 0.5$. The ratio is measured to be $R_{|y| < 0.5} = 0.957 \\pm 0.006 (stat.) \\pm 0.014 (syst.)$ at $0.9$~TeV and $R_{|y| < 0.5} = 0.991 \\pm 0.005 (stat.) \\pm 0.014 (syst.)$ at $7$~TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.

  19. New results on strong-interaction effects in antiprotonic hydrogen

    CERN Document Server

    Gotta, D; Augsburger, M A; Borchert, G L; Castelli, C M; Chatellard, D; El-Khoury, P; Egger, J P; Gorke, H; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Nelms, N; Rashid, K; Schult, O W B; Siems, T; Simons, L M

    1999-01-01

    Lyman and Balmer transitions of antiprotonic hydrogen and deuterium have been measured at the low-energy antiproton ring LEAR at CERN in order to determine the strong interaction effects. The X-rays were detected using charge-coupled devices (CCDs) and a reflection type crystal spectrometer. The results of the measurements support the meson-exchange models describing the medium and long range part of the nucleon-antinucleon interaction. (33 refs).

  20. New results on strong-interaction effects in antiprotonic hydrogen

    International Nuclear Information System (INIS)

    Anagnostopoulos, D. F.; Augsburger, M.; Borchert, G.; Castelli, C.; Chatellard, D.; El-Khoury, P.; Egger, J.-P.; Gorke, H.; Gotta, D.; Hauser, P.; Indelicato, P.; Kirch, K.; Lenz, S.; Nelms, N.; Rashid, K.; Schult, O. W. B.; Siems, Th.; Simons, L. M.

    1999-01-01

    Lyman and Balmer transitions of antiprotonic hydrogen and deuterium have been measured at the Low-Energy Antiproton Ring LEAR at CERN in order to determine the strong interaction effects. The X-rays were detected using Charge-Coupled Devices (CCDs) and a reflection type crystal spectrometer. The results of the measurements support the meson-exchange models describing the medium and long range part of the nucleon-antinucleon interaction

  1. Radiotherapy

    International Nuclear Information System (INIS)

    Pistenma, D.A.

    1980-01-01

    The need for radiotherapy research is exemplified by the 100,000 cancer patients who will fail treatment locally and/or regionally annually for the next several years but who would benefit from better local treatment modalities. Theoretically, all of the areas of investigation discussed in this projection paper have the potential to significantly improve local-regional treatment of cancer by radiotherapy alone or in combination with other modalities. In many of the areas of investigation discussed in this paper encouraging results have been obtained in cellular and animal tumor studies and in limited studies in humans as well. In the not too distant future the number of patients who would benefit from better local control may increase by tens of thousands if developments in chemotherapy and/or immunotherapy provide a means to eradicate disseminated microscopic foci of cancer. Thus the efforts to improve local-regional control take on even greater significance

  2. Shielding experiments by the JASMIN collaboration at Fermilab (II) - Radioactivity measurement induced by secondary particles from the anti-proton production target

    Energy Technology Data Exchange (ETDEWEB)

    Yashima, Hiroshi; /Kyoto U., KURRI; Matsuda, Norihiro; Kasugai, Yoshimi; /JAEA, Ibaraki; Matsumura, Hiroshi; Iwase, Hiroshi; /KEK, Tsukuba; Kinoshita, Norikazu; /KEK, Tsukuba /Tsukuba U.; Boehnlein, David; Lauten, Gary; Leveling, Anthony; Mokhov, Nikolai; Vaziri, Kamran; /Fermilab /Shimizu, Tokyo /JAEA, Ibaraki

    2011-01-01

    The JASMIN Collaboration has performed an experiment to conduct measurements of nuclear reaction rates around the anti-proton production (Pbar) target at the Fermi National Accelerator Laboratory (FNAL). At the Pbar target station, the target, consisting an Inconel 600 cylinder, was irradiated by a 120 GeV/c proton beam from the FNAL Main Injector. The beam intensity was 3.6 x 10{sub 12} protons per second. Samples of Al, Nb, Cu, and Au were placed near the target to investigate the spatial and energy distribution of secondary particles emitted from it. After irradiation, the induced activities of the samples were measured by studying their gamma ray spectra using HPGe detectors. The production rates of 30 nuclides induced in Al, Nb, Cu, Au samples were obtained. These rates increase for samples placed in a forward (small angle) position relative to the target. The angular dependence of these reaction rates becomes larger for increasing threshold energy. These experimental results are compared with Monte Carlo calculations. The calculated results generally agree with the experimental results to within a factor of 2 to 3.

  3. Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at $\\sqrt{s_{NN}}$=2.76 TeV

    CERN Document Server

    Abelev, Betty; Adamova, Dagmar; Adare, Andrew Marshall; Aggarwal, Madan; Aglieri Rinella, Gianluca; Agocs, Andras Gabor; Agostinelli, Andrea; Aguilar Salazar, Saul; Ahammed, Zubayer; Ahmad, Arshad; Ahmad, Nazeer; Ahn, Sang Un; Akindinov, Alexander; Aleksandrov, Dmitry; Alessandro, Bruno; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Almaraz Avina, Erick Jonathan; Alme, Johan; Alt, Torsten; Altini, Valerio; Altinpinar, Sedat; Altsybeev, Igor; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshauser, Harald; Arbor, Nicolas; Arcelli, Silvia; Armesto, Nestor; Arnaldi, Roberta; Aronsson, Tomas Robert; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Awes, Terry; Aysto, Juha Heikki; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bailhache, Raphaelle Marie; Bala, Renu; Baldini Ferroli, Rinaldo; Baldisseri, Alberto; Baldit, Alain; Baltasar Dos Santos Pedrosa, Fernando; Ban, Jaroslav; Baral, Rama Chandra; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Barret, Valerie; Bartke, Jerzy Gustaw; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batyunya, Boris; Baumann, Christoph Heinrich; Bearden, Ian Gardner; Beck, Hans; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bellwied, Rene; Belmont-Moreno, Ernesto; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bergognon, Anais Annick Erica; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhati, Ashok Kumar; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Bjelogrlic, Sandro; Blanco, F; Blanco, Francesco; Blau, Dmitry; Blume, Christoph; Bock, Nicolas; Boettger, Stefan; Bogdanov, Alexey; Boggild, Hans; Bogolyubsky, Mikhail; Boldizsar, Laszlo; Bombara, Marek; Book, Julian; Borel, Herve; Borissov, Alexander; Bose, Suvendu Nath; Bossu, Francesco; Botje, Michiel; Boyer, Bruno Alexandre; Braidot, Ermes; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Browning, Tyler Allen; Broz, Michal; Brun, Rene; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Bugaiev, Kyrylo; Busch, Oliver; Buthelezi, Edith Zinhle; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calvo Villar, Ernesto; Camerini, Paolo; Canoa Roman, Veronica; Cara Romeo, Giovanni; Carena, Francesco; Carena, Wisla; Carminati, Federico; Casanova Diaz, Amaya Ofelia; Castillo Castellanos, Javier Ernesto; Casula, Ester Anna Rita; Catanescu, Vasile; Cavicchioli, Costanza; Ceballos Sanchez, Cesar; Cepila, Jan; Cerello, Piergiorgio; Chang, Beomsu; Chapeland, Sylvain; Charvet, Jean-Luc Fernand; Chattopadhyay, Sukalyan; Chattopadhyay, Subhasis; Chawla, Isha; Cherney, Michael Gerard; Cheshkov, Cvetan; Cheynis, Brigitte; Chiavassa, Emilio; Chibante Barroso, Vasco Miguel; Chinellato, David; Chochula, Peter; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Coccetti, Fabrizio; Colamaria, Fabio; Colella, Domenico; Conesa Balbastre, Gustavo; Conesa del Valle, Zaida; Constantin, Paul; Contin, Giacomo; Contreras, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Cotallo, Manuel Enrique; Crochet, Philippe; Cruz Alaniz, Emilia; Cuautle, Eleazar; Cunqueiro, Leticia; D'Erasmo, Ginevra; Dainese, Andrea; Dalsgaard, Hans Hjersing; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Kushal; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; de Barros, Gabriel; De Caro, Annalisa; de Cataldo, Giacinto; de Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; de Rooij, Raoul Stefan; Delagrange, Hugues; Deloff, Andrzej; Demanov, Vyacheslav; Denes, Ervin; Deppman, Airton; Di Bari, Domenico; Di Giglio, Carmelo; Di Liberto, Sergio; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Dominguez, Isabel; Donigus, Benjamin; Dordic, Olja; Driga, Olga; Dubey, Anand Kumar; Ducroux, Laurent; Dupieux, Pascal; Dutta Majumdar, AK; Dutta Majumdar, Mihir Ranjan; Elia, Domenico; Emschermann, David Philip; Engel, Heiko; Erdal, Hege Austrheim; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Evans, David; Eyyubova, Gyulnara; Fabris, Daniela; Faivre, Julien; Falchieri, Davide; Fantoni, Alessandra; Fasel, Markus; Fearick, Roger Worsley; Fedunov, Anatoly; Fehlker, Dominik; Feldkamp, Linus; Felea, Daniel; Fenton-Olsen, Bo; Feofilov, Grigory; Fernandez Tellez, Arturo; Ferretti, Alessandro; Ferretti, Roberta; Figiel, Jan; Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Frankenfeld, Ulrich Michael; Fuchs, Ulrich; Furget, Christophe; Fusco Girard, Mario; Gaardhoje, Jens Joergen; Gagliardi, Martino; Gago, Alberto; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Garabatos, Jose; Garcia-Solis, Edmundo; Garishvili, Irakli; Gerhard, Jochen; Germain, Marie; Geuna, Claudio; Gheata, Andrei George; Gheata, Mihaela; Ghidini, Bruno; Ghosh, Premomoy; Gianotti, Paola; Girard, Martin Robert; Giubellino, Paolo; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez, Ramon; Gonschior, Alexey; Gonzalez Ferreiro, Elena; Gonzalez-Trueba, Laura Helena; Gonzalez-Zamora, Pedro; Gorbunov, Sergey; Goswami, Ankita; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Grajcarek, Robert; Grelli, Alessandro; Grigoras, Alina Gabriela; Grigoras, Costin; Grigoriev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Grinyov, Boris; Grion, Nevio; Grosse-Oetringhaus, Jan Fiete; Grossiord, Jean-Yves; Grosso, Raffaele; Guber, Fedor; Guernane, Rachid; Guerra Gutierrez, Cesar; Guerzoni, Barbara; Guilbaud, Maxime Rene Joseph; Gulbrandsen, Kristjan Herlache; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Gutbrod, Hans; Haaland, Oystein Senneset; Hadjidakis, Cynthia Marie; Haiduc, Maria; Hamagaki, Hideki; Hamar, Gergoe; Hanratty, Luke David; Hansen, Alexander; Harmanova, Zuzana; Harris, John William; Hartig, Matthias; Hasegan, Dumitru; Hatzifotiadou, Despoina; Hayrapetyan, Arsen; Heckel, Stefan Thomas; Heide, Markus Ansgar; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Herrera Corral, Gerardo Antonio; Herrmann, Norbert; Hess, Benjamin Andreas; Hetland, Kristin Fanebust; Hicks, Bernard; Hille, Per Thomas; Hippolyte, Boris; Horaguchi, Takuma; Hori, Yasuto; Hristov, Peter Zahariev; Hrivnacova, Ivana; Huang, Meidana; Humanic, Thomas; Hwang, Dae Sung; Ichou, Raphaelle; Ilkaev, Radiy; Ilkiv, Iryna; Inaba, Motoi; Incani, Elisa; Innocenti, Gian Michele; Ippolitov, Mikhail; Irfan, Muhammad; Ivan, Cristian George; Ivanov, Andrey; Ivanov, Marian; Ivanov, Vladimir; Ivanytskyi, Oleksii; Jacholkowski, Adam Wlodzimierz; Jacobs, Peter; Jangal, Swensy Gwladys; Janik, Malgorzata Anna; Janik, Rudolf; Jayarathna, Sandun; Jena, Satyajit; Jha, Deeptanshu Manu; Jimenez Bustamante, Raul Tonatiuh; Jirden, Lennart; Jones, Peter Graham; Jung, Hyung Taik; Jusko, Anton; Kakoyan, Vanik; Kalcher, Sebastian; Kalinak, Peter; Kalliokoski, Tuomo Esa Aukusti; Kalweit, Alexander Philipp; Kanaki, Kalliopi; Kang, Ju Hwan; Kaplin, Vladimir; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karpechev, Evgeny; Kazantsev, Andrey; Kebschull, Udo Wolfgang; Keidel, Ralf; Khan, Mohisin Mohammed; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Dong Jo; Kim, Do Won; Kim, Jonghyun; Kim, Jin Sook; Kim, Minwoo; Kim, Mimae; Kim, Se Yong; Kim, Seon Hee; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Klay, Jennifer Lynn; Klein, Jochen; Klein-Bosing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Koch, Kathrin; Kohler, Markus; Kolojvari, Anatoly; Kondratiev, Valery; Kondratyeva, Natalia; Konevskih, Artem; Korneev, Andrey; Kour, Ravjeet; Kowalski, Marek; Kox, Serge; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kramer, Frederick; Kraus, Ingrid Christine; Krawutschke, Tobias; Krelina, Michal; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Krus, Miroslav; Kryshen, Evgeny; Krzewicki, Mikolaj; Kucheriaev, Yury; Kuhn, Christian Claude; Kuijer, Paul; Kulakov, Igor; Kurashvili, Podist; Kurepin, A; Kurepin, AB; Kuryakin, Alexey; Kushpil, Svetlana; Kushpil, Vasily; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Ladron de Guevara, Pedro; Lakomov, Igor; Langoy, Rune; Lara, Camilo Ernesto; Lardeux, Antoine Xavier; Lazzeroni, Cristina; Le Bornec, Yves; Lea, Ramona; Lechman, Mateusz; Lee, Graham Richard; Lee, Ki Sang; Lee, Sung Chul; Lefevre, Frederic; Lehnert, Joerg Walter; Leistam, Lars; Lemmon, Roy Crawford; Lenhardt, Matthieu Laurent; Lenti, Vito; Leon Monzon, Ildefonso; Leon Vargas, Hermes; Leoncino, Marco; Levai, Peter; Lien, Jorgen; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Liu, Lijiao; Loenne, Per-Ivar; Loggins, Vera; Loginov, Vitaly; Lohn, Stefan Bernhard; Lohner, Daniel; Loizides, Constantinos; Loo, Kai Krister; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lovhoiden, Gunnar; Lu, Xianguo; Luettig, Philipp; Lunardon, Marcello; Luo, Jiebin; Luparello, Grazia; Luquin, Lionel; Luzzi, Cinzia; Ma, Rongrong; Maevskaya, Alla; Mager, Magnus; Mahapatra, Durga Prasad; Maire, Antonin; Mal'Kevich, Dmitry; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Ludmila; Malzacher, Peter; Mamonov, Alexander; Manceau, Loic Henri Antoine; Manko, Vladislav; Manso, Franck; Manzari, Vito; Mao, Yaxian; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Marin, Ana Maria; Marin Tobon, Cesar Augusto; Markert, Christina; Martashvili, Irakli; Martinengo, Paolo; Martinez, Mario Ivan; Martinez Davalos, Arnulfo; Martinez Garcia, Gines; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Mastromarco, Mario; Mastroserio, Annalisa; Matthews, Zoe Louise; Matyja, Adam Tomasz; Mayani, Daniel; Mayer, Christoph; Mazer, Joel; Mazzoni, Alessandra Maria; Meddi, Franco; Menchaca-Rocha, Arturo Alejandro; Mercado Perez, Jorge; Meres, Michal; Miake, Yasuo; Milano, Leonardo; Milosevic, Jovan; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz; Mitu, Ciprian Mihai; Mlynarz, Jocelyn; Mohanty, Ajit Kumar; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Monteno, Marco; Montes, Esther; Moon, Taebong; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Moretto, Sandra; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhuri, Sanjib; Mukherjee, Maitreyee; Muller, Hans; Munhoz, Marcelo; Musa, Luciano; Musso, Alfredo; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Nattrass, Christine; Naumov, Nikolay; Navin, Sparsh; Nayak, Tapan Kumar; Nazarenko, Sergey; Nazarov, Gleb; Nedosekin, Alexander; Nicassio, Maria; Niculescu, Mihai; Nielsen, Borge Svane; Niida, Takafumi; Nikolaev, Sergey; Nikolic, Vedran; Nikulin, Sergey; Nikulin, Vladimir; Nilsen, Bjorn Steven; Nilsson, Mads Stormo; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Novitzky, Norbert; Nyanin, Alexandre; Nyatha, Anitha; Nygaard, Casper; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Oleniacz, Janusz; Oppedisano, Chiara; Ortona, Giacomo; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Pachmayer, Yvonne Chiara; Pachr, Milos; Padilla, Fatima; Pagano, Paola; Paic, Guy; Painke, Florian; Pajares, Carlos; Pal, S; Pal, Susanta Kumar; Palaha, Arvinder Singh; Palmeri, Armando; Papikyan, Vardanush; Pappalardo, Giuseppe; Park, Woo Jin; Passfeld, Annika; Patalakha, Dmitri Ivanovich; Paticchio, Vincenzo; Pavlinov, Alexei; Pawlak, Tomasz Jan; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitri; Perez Lara, Carlos Eugenio; Perez Lezama, Edgar; Perini, Diego; Perrino, Davide; Peryt, Wiktor Stanislaw; Pesci, Alessandro; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petran, Michal; Petris, Mariana; Petrov, Plamen Rumenov; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Piccotti, Anna; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Pitz, Nora; Piuz, Francois; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polichtchouk, Boris; Pop, Amalia; Porteboeuf-Houssais, Sarah; Pospisil, Vladimir; Potukuchi, Baba; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puchagin, Sergey; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Pujol Teixido, Jordi; Pulvirenti, Alberto; Punin, Valery; Putis, Marian; Putschke, Jorn Henning; Quercigh, Emanuele; Qvigstad, Henrik; Rachevski, Alexandre; Rademakers, Alphonse; Radomski, Sylwester; Raiha, Tomi Samuli; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Ramirez Reyes, Abdiel; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reichelt, Patrick; Reicher, Martijn; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riccati, Lodovico; Ricci, Renato Angelo; Richert, Tuva; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Rodrigues Fernandes Rabacal, Bartolomeu; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roed, Ketil; Rohr, David; Rohrich, Dieter; Romita, Rosa; Ronchetti, Federico; Rosnet, Philippe; Rossegger, Stefan; Rossi, Andrea; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Rybicki, Andrzej; Sadovsky, Sergey; Safarik, Karel; Sahoo, Raghunath; Sahu, Pradip Kumar; Saini, Jogender; Sakaguchi, Hiroaki; Sakai, Shingo; Sakata, Dosatsu; Salgado, Carlos Albert; Salzwedel, Jai; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sanchez Castro, Xitzel; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Sano, Satoshi; Santo, Rainer; Santoro, Romualdo; Sarkamo, Juho Jaako; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schreiner, Steffen; Schuchmann, Simone; Schukraft, Jurgen; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Patrick Aaron; Scott, Rebecca; Segato, Gianfranco; Selyuzhenkov, Ilya; Senyukov, Serhiy; Seo, Jeewon; Serci, Sergio; Serradilla, Eulogio; Sevcenco, Adrian; Shabetai, Alexandre; Shabratova, Galina; Shahoyan, Ruben; Sharma, Natasha; Sharma, Satish; Shigaki, Kenta; Shimomura, Maya; Shtejer, Katherin; Sibiriak, Yury; Siciliano, Melinda; Sicking, Eva; Siddhanta, Sabyasachi; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, catherine; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Skjerdal, Kyrre; Smakal, Radek; Smirnov, Nikolai; Snellings, Raimond; Sogaard, Carsten; Soltz, Ron Ariel; Son, Hyungsuk; Song, Jihye; Song, Myunggeun; Soos, Csaba; Soramel, Francesca; Sputowska, Iwona; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Stefanini, Giorgio; Steinbeck, Timm Morten; Steinpreis, Matthew; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Stolpovskiy, Mikhail; Strabykin, Kirill; Strmen, Peter; Suaide, Alexandre Alarcon do Passo; Subieta Vasquez, Martin Alfonso; Sugitate, Toru; Suire, Christophe Pierre; Sukhorukov, Mikhail; Sultanov, Rishat; Sumbera, Michal; Susa, Tatjana; Szanto de Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szostak, Artur Krzysztof; Szymanski, Maciej; Takahashi, Jun; Tapia Takaki, Daniel Jesus; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terrevoli, Cristina; Thader, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony; Toia, Alberica; Torii, Hisayuki; Tosello, Flavio; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ulery, Jason Glyndwr; Ullaland, Kjetil; Ulrich, Jochen; Uras, Antonio; Urban, Jozef; Urciuoli, Guido Marie; Usai, Gianluca; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; van der Kolk, Naomi; van Leeuwen, Marco; Vande Vyvre, Pierre; Vannucci, Luigi; Vargas, Aurora Diozcora; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vechernin, Vladimir; Veldhoen, Misha; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Vikhlyantsev, Oleg; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Viyogi, Yogendra; Vodopianov, Alexander; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; von Haller, Barthelemy; Vranic, Danilo; Øvrebekk, Gaute; Vrlakova, Janka; Vulpescu, Bogdan; Vyushin, Alexey; Wagner, Boris; Wagner, Vladimir; Wan, Renzhuo; Wang, Dong; Wang, Mengliang; Wang, Yifei; Wang, Yaping; Watanabe, Kengo; Weber, Michael; Wessels, Johannes; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Alexander; Wilk, Grzegorz Andrzej; Williams, Crispin; Windelband, Bernd Stefan; Xaplanteris Karampatsos, Leonidas; Yaldo, Chris G; Yamaguchi, Yorito; Yang, Hongyan; Yang, Shiming; Yasnopolsky, Stanislav; Yi, JunGyu; Yin, Zhongbao; Yoo, In-Kwon; Yoon, Jongik; Yu, Weilin; Yuan, Xianbao; Yushmanov, Igor; Zach, Cenek; Zampolli, Chiara; Zaporozhets, Sergey; Zarochentsev, Andrey; Zavada, Petr; Zaviyalov, Nikolai; Zbroszczyk, Hanna Paulina; Zelnicek, Pierre; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhou, Daicui; Zhou, Fengchu; Zhou, You; Zhu, Jianhui; Zhu, Xiangrong; Zichichi, Antonino; Zimmermann, Alice; Zinovjev, Gennady; Zoccarato, Yannick Denis; Zynovyev, Mykhaylo; Zyzak, Maksym

    2013-02-12

    The elliptic, $v_2$, triangular, $v_3$, and quadrangular, $v_4$, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions, and (anti-)protons in Pb–Pb collisions at $\\sqrt{s_{NN}}$ = 2.76 TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range |$\\eta$|8 GeV/c. The small $p_T$ dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to $p_T$ =8 GeV/c. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least $p_T$ =8 GeV/c indicating that the particle type dependence persists out to high $p_T$.

  4. Testing Quantum Chromodynamics with Antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, S.

    2004-10-21

    The antiproton storage ring HESR to be constructed at GSI will open up a new range of perturbative and nonperturbative tests of QCD in exclusive and inclusive reactions. I discuss 21 tests of QCD using antiproton beams which can illuminate novel features of QCD. The proposed experiments include the formation of exotic hadrons, measurements of timelike generalized parton distributions, the production of charm at threshold, transversity measurements in Drell-Yan reactions, and searches for single-spin asymmetries. The interactions of antiprotons in nuclear targets will allow tests of exotic nuclear phenomena such as color transparency, hidden color, reduced nuclear amplitudes, and the non-universality of nuclear antishadowing. The central tool used in these lectures are light-front Fock state wavefunctions which encode the bound-state properties of hadrons in terms of their quark and gluon degrees of freedom at the amplitude level. The freedom to choose the light-like quantization four-vector provides an explicitly covariant formulation of light-front quantization and can be used to determine the analytic structure of light-front wave functions. QCD becomes scale free and conformally symmetric in the analytic limit of zero quark mass and zero {beta} function. This ''conformal correspondence principle'' determines the form of the expansion polynomials for distribution amplitudes and the behavior of non-perturbative wavefunctions which control hard exclusive processes at leading twist. The conformal template also can be used to derive commensurate scale relations which connect observables in QCD without scale or scheme ambiguity. The AdS/CFT correspondence of large N{sub C} supergravity theory in higher-dimensional anti-de Sitter space with supersymmetric QCD in 4-dimensional space-time has important implications for hadron phenomenology in the conformal limit, including the nonperturbative derivation of counting rules for exclusive processes and

  5. Low grade glioma : a measuring radiographic response to radiotherapy

    International Nuclear Information System (INIS)

    Bauman, G.; Pahapill, P.; Macdonald, D.; Fisher, B.; Leighton, C.; Cairncross, G.

    1999-01-01

    Purpose: We set out to determine the rate of response of low-grade (WHO Grade II) gliomas to radiotherapy and analyze the relationship between radiographic response, symptom control and patient survival. Methods: Patients were eligible for this study if they had received radiotherapy for pathologically confirmed, residual, supratentorial low-grade astrocytoma, oligodendroglioma, or mixed glioma, and imaging studies (baseline and follow-up) were available for review. Percent change in tumor size and rate and timing of response were determined by maximum linear measurement, area measurement, volume measurement using an ellipsoid model, and volume measurement by image segmentation. For each method, response to radiotherapy was defined firstly as a ≥ 50% decrease in tumor size (partial response), and secondly as a decrease equivalent to a 50% area decrease (normalized partial response). Relationships between radiographic response, clinical improvement and progression-free survival were analyzed using a Cox Proportional Hazard's model. Results: Twenty-one patients in a database (13 male, 8 female; ages 22-66 years) met the eligibility criteria. Twenty were imaged by computed tomography, 18 had an astrocytoma and 15 were irradiated soon after surgery. Responses were common and not felt to be due to a steroid effect. Use of normalized response criteria improved agreement between assessment of response as determined by the 4 methods. Median time to maximum radiographic improvement was 2.8 months (range, 1.5-11). Sixteen patients (76%) were improved neurologically, the median time to progression was 4.8 years and the 5-year progression-free survival rate was 43%. We did not detect a statistically significant association between response (as measured by any method), symptomatology and progression-free survival. Conclusions: Low-grade gliomas are moderately radioresponsive. Use of volume measurement may over-estimate the number of partial responses unless a volume reduction

  6. Lung density as measured by computerized tomography: implications for radiotherapy

    International Nuclear Information System (INIS)

    Van Dyk, J.; Keane, T.J.; Rider, W.D.

    1982-01-01

    Accurate dose calculations for radiotherapy planning require a detailed knowledge of the internal anatomy of the patient both in terms of geometry and density. Computed tomography (CT) is presently the best means of providing these data. Fifty-eight patients who had scans of the thorax for radiotherapy planning were studied. The CT numbers were converted to relative electron densities and average lung densities were obtained for every patient. A linear correlation of lung density with age was found with the mean lung density of 0.35 at an age 5 years and 0.19 at an age of 80. The effect of scanning the patient under full inspiration, full expiration or normal shallow breathing conditions was analyzed. At the age of 5 years the expiration and inspiration average lung densities were 0.36 and 0.20, while at the age of 80 years they were 0.22 and 0.16, respectively. Respiratory volume changes were linearly correlated with changes in relative electron density. Differences in lung density between expiration and inspiration scans were found to demonstrate a similar trend with age as the relationship between vital capacity and age. The dosimetric and the possible clinical implications of lung density measurements for radiotherapy are considered. In particular, dose calculations were performed using scans taken under a number of different respiratory conditions. Doses calculated for a single cobalt-60 beam can differ by more than 25% when comparing a full inspiration scan to a normal breathing scan. A similar comparison for a parallel pair distribution on the lung yields a difference of about 3% while a typical three field technique for treating cancer of the esophagus shows a difference of nearly 10%

  7. Measurement of Event Shapes in Proton-Antiproton Collisions at Center-of-Mass Energy 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, T.; Aaltonen, T.; /Helsinki Inst. of Phys.; Alvarez Gonzalez, B.; /Oviedo U. /Cantabria Inst. of Phys.; Amerio, S.; /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Appel, J.A.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U. /Dubna, JINR

    2011-03-01

    A study of event shape observables in proton-antiproton collisions at {radical}s = 1.96 TeV is presented. The data for this analysis were recorded by the CDF II detector at the Tevatron collider. The variables studied are the transverse thrust and thrust minor, both defined in the plane perpendicular to the beam direction. The observables are measured using energies from unclustered calorimeter cells. In addition to studies of the differential distributions, we present the dependence of event shape mean values on the leading jet transverse energy. Data are compared with pythia Tune A and to resummed parton level predictions that were matched to fixed order results at NLO accuracy (NLO+NLL). Predictions from pythia Tune A agree fairly well with the data. However, the underlying event contributes significantly to these observables, making it difficult to make direct comparisons to the NLO+NLL predictions, which do not account for the underlying event. To overcome this difficulty, we introduce a new observable, a weighted difference of the mean values of the thrust and thrust minor, which is less sensitive to the underlying event, allowing for a comparison with NLO+NLL. Both pythia Tune A and the NLO+NLL calculations agree well within the 20% theoretical uncertainty with the data for this observable, indicating that perturbative QCD successfully describes shapes of the hadronic final states.

  8. Centrality dependence of antiproton production in Au+Au collisions

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D.; Bennett, M.J.; Carroll, J.B.; Chiba, J.; Chikanian, A.; Crawford, H.; Cronqvist, M.; Dardenne, Y.; Debbe, R.; Doke, T.; Engelage, J.; Greiner, L.; Hallman, T.J.; Hayano, R.S.; Heckman, H.H.; Kashiwagi, T.; Kikuchi, J.; Kumar, S.; Kuo, C.; Lindstrom, P.J.; Mitchell, J.W.; Nagamiya, S.; Nagle, J.L.; Pope, J.K.; Stankus, P.; Tanaka, K.H.; Welsh, R.C.; Zhan, W. [Brookhaven National Laboratory, Upton, New York (United States)]|[A.W. Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut (United States)]|[University of California at Los Angeles, Los Angeles California (United States)]|[National Laboratory for High Energy Physics (KEK), Tsukuba (Japan)]|[University of California Space Sciences Laboratory, Berkeley California (United States)]|[Waseda University, Tokyo (Japan)]|[University of Tokyo, Tokyo (Japan)]|[Lawrence Berkeley Laboratory, Berkeley California (United States)]|[Universities Space Sciences Research Association/Goddard Space Flight Center, Greenbelt, Maryland (United States)]|[Nevis Laboratory, Columbia University, Irvington, New York (United States)]|[Johns Hopkins University, Baltimore, Maryland (United States); (E878 Collaboration)

    1995-11-13

    We have measured the yields of antiprotons in Au+Au interactions in the rapidity range 1.2{lt}{ital y}{lt}2.8 as a function of centrality using a beam line spectrometer. The shapes of the invariant multiplicity distributions at {ital p}{sub {ital t}}=0 are used to explore the dynamics of antiproton production and annihilation. {copyright} {ital 1995} {ital The} {ital American} {ital Physical} {ital Society}.

  9. AA antiproton production target

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing of stainless steel. At the entrance to the target assembly was a scintillator screen, imprinted with circles every 5 mm in radius, which allowed to precisely aim the 26 GeV high-intensity proton beam from the PS onto the centre of the target rod. The scintillator screen was a 1 mm thick plate of Cr-doped alumina. See also 7903034 and 7905091.

  10. AA antiproton production target

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    The first version of the antiproton production target was a tungsten rod, 11 cm long (actually a row of 11 rods, each 1 cm long) and 3 mm in diameter. The rod was embedded in graphite, pressure-seated into an outer casing made of stainless steel. The casing had fins for forced-air cooling. In this picture, the 26 GeV high-intensity beam from the PS enters from the right, where a scintillator screen, with circles every 5 mm in radius, permits precise aim at the target centre. See also 7903034 and 7905094.

  11. Experiments on Antiprotons: Cross Sections of Complex Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Agnew, Jr., Lewis E.; Chamberlain, Owen; Keller, Donald V.; Mermod, Ronald; Rogers, Ernest H.; Steiner, Herbert M.; Wiegand, Clyde

    1957-07-22

    Experiments are described that have been designed to measure separately annihilation and reaction cross sections for antiprotons of approximately 450 MeV on oxygen, copper, silver, and lead. A new and more luminous spectrograph has been built for this experiment. The antiproton cross sections a r e compared with total proton cross sections, and are found to be larger by a factor varying from 1.74 for oxygen to 1.39 for silver. Calculations based on the optical model give a reasonable connection between these cross sections and the 6-p and 6-n cross sections. Finally, the information available on antiproton production cross sections is collected. There are indications that a free nucleon is several times as effective as a bound one for producing antiprotons.

  12. Measurement of Z+ γ production and search for anomalous triple gauge couplings in proton-antiproton collisions at √S = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jianrong [Duke Univ., Durham, NC (United States)

    2008-01-01

    The author presents a measurement of p$\\bar{p}$ → Zγ + X → e+e-γ + X production using proton-antiproton collisions data collected at the Collider Detector at Fermilab at a center of mass energy of 1.96 TeV. Zγ production provides a direct test of the triple neutral gauge couplings. A measurement of Zγ production cross section and search for anomalous ZZγ and Zγγ couplings are presented. The data presented are from 1.1 fb-1 of p$\\bar{p}$ integrated luminosity collected at the CDF Detector. Electrons from Z decays are selected with Et > 20 Gev. Photons (Et > 7 GeV) are required to be well-separated from the electrons. There are 390 eeγ candidate events found with 1.1 fb-1 of data, compared to the SM prediction of 375.3 ± 25.2 events. The Standard Model prediction for the cross section for p$\\bar{p}$ → e+e-γ + X production at √s = 1.96 TeV is 4.5 ± 0.4 pb. The measured cross section is 4.7 ± 0.6 pb. The cross section and kinematic distributions of the eeγ events are in good agreement with theoretical predictions. Limits on the ZZγ and Zγγ couplings are extracted using the photon Et distribution of eeγ events with meeγ > 100 GeV/c2. These are the first limits measured using CDF Run II data. These limits provide important test of the interaction of the photon and the Z boson.

  13. Antiproton complex at the FAIR project

    International Nuclear Information System (INIS)

    Dolinskii, A.; Knie, K.; Dimopoulou, C.; Gostishchev, V.; Litvinov, S.; Nolden, F.; Steck, M.

    2011-01-01

    This report summarizes a set of calculations for the antiproton production in a complex composed of target area, collector, separator, beam line and collector ring for the antiproton source of the future FAIR facility (Facility for Antiproton and Ion Research) at GSI, Darmstadt, Germany. The emphasis is on the optimization of the accumulation rate of antiprotons in order to maximize the luminosity of experiments with cooled antiproton beams in the High Energy Storage Ring (HESR). Results of simulations for each component of the antiproton production complex are presented in order to identify the present limitations of the antiproton production rate.

  14. Centrifugal Separation of Antiprotons and Electrons

    CERN Document Server

    Gabrielse, G; McConnell, R; Richerme, P; Wrubel, J; Kalra, R; Novitski, E; Grzonka, D; Oelert, W; Sefzick, T; Zielinski, M; Borbely, J S; Fitzakerley, D; George, M C; Hessels, E A; Storry, C H; Weel, M; Mullers, A; Walz, J; Speck, A

    2010-01-01

    Centrifugal separation of antiprotons and electrons is observed, the first such demonstration with particles that cannot be laser cooled or optically imaged. The spatial separation takes place during the electron cooling of trapped antiprotons, the only method available to produce cryogenic antiprotons for precision tests of fundamental symmetries and for cold antihydrogen studies. The centrifugal separation suggests a new approach for isolating low energy antiprotons and for producing a controlled mixture of antiprotons and electrons.

  15. Nuclear stopping power of antiprotons

    Science.gov (United States)

    Nordlund, Kai; Sundholm, Dage; Pyykkö, Pekka; Zambrano, Daniel Martinez; Djurabekova, Flyura

    2017-10-01

    The slowing down of energetic ions in materials is determined by the nuclear and electronic stopping powers. Both of these have been studied extensively for ordinary-matter ions. For antiprotons, however, there are numerous studies of the electronic stopping power, but none of the nuclear stopping power. Here, we use quantum-chemical methods to calculate interparticle potentials between antiprotons and different atoms, and derive from these the nuclear stopping power of antiprotons in solids. The results show that the antiproton nuclear stopping powers are much stronger than those of protons, and can also be stronger than the electronic stopping power at the lowest energies. The interparticle potentials are also implemented in a molecular dynamics ion range calculation code, which allows us to simulate antiproton transmission through degrader foil materials. Foil transmission simulations carried out at experimentally relevant conditions show that the choice of antiproton-atom interaction model has a large effect on the predicted yield of antiprotons slowed down to low (a few keV) energies.

  16. Radiotherapy

    International Nuclear Information System (INIS)

    Hubert, D.

    2009-01-01

    Context: the descendants of persons treated for a childhood cancer could have an increased risk of genetic disease because of mutagenic anti cancerous treatments received by their parents. 3963 survivors of cancer in childhood ( born between 12950 and 1984) have been identified from the Danish register of cancer, constituting the 'survivors' cohort. 5657 of their brothers and sisters constituting the 'siblings' cohort have been identified from the Danish central register of the population. All of the live-born children born from these two cohorts have been identified from this register, allowing to include 1715 descendants from the 'survivors' cohort and 6009 descendants from the 'siblings' cohort. The congenital malformations have been found out from the national hospital register. The irradiation doses to the gonads and uterus have been defined by using the usual radiotherapy protocols. Conclusion: This study shows that the anti cancerous treatments for children do not seem increase the risk of congenital malformations in their progeny. (N.C.)

  17. Proton-antiproton collider physics

    CERN Document Server

    Altarelli, Guido

    1989-01-01

    This volume reviews the physics studied at the CERN proton-antiproton collider during its first phase of operation, from the first physics run in 1981 to the last one at the end of 1985. The volume consists of a series of review articles written by physicists who are actively involved with the collider research program. The first article describes the proton-antiproton collider facility itself, including the antiproton source and its principle of operation based on stochastic cooling. The subsequent six articles deal with the various physics subjects studied at the collider. Each article descr

  18. Intensity-Frontier Antiproton Physics with The Antiproton Annihilation Spectrometer (TAPAS) at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Apollinari, Giorgio; /Fermilab; Asner, David M.; /PNL, Richland; Baldini, Wander; /INFN, Ferrara; Bartoszek, Larry; Broemmelsiek, Daniel R.; Brown, Charles N.; /Fermilab; Chakravorty, Alak; /St. Xavier U., Chicago; Colas, Paul; /Saclay; Derwent, Paul; /Fermilab; Drutskoy, Alexey; /Moscow, ITEP; Fortner, Michael; /Northern Illinois U. /Saclay /Indian Inst. Tech., Hyderabad

    2011-11-01

    The Fermilab Antiproton Source is the world's most intense source of antimatter. With the Tevatron program now behind us, this unique facility can help make the case for Fermilab's continued accelerator operations. The Antiproton Source can be used for unique, dedicated antimatter studies, including medium-energy {bar p}-annihilation experiments. We propose to assemble a powerful, yet cost-effective, solenoidal magnetic spectrometer for antiproton-annihilation events, and to use it at the Fermilab Antiproton Accumulator to measure the charm production cross section, study rare hyperon decays, search for hyperon CP asymmetry, precisely measure the properties of several charmonium and nearby states, and make the first measurements of the Drell-Yan continuum in medium-energy antiproton annihilation. Should the charm production cross section be as large as some have proposed, we will also be able to measure D{sup 0}-{bar D}{sup 0} mixing with high precision and discover (or sensitively limit) charm CP violation. The observation of charm or hyperon CP violation would be evidence for physics beyond the Standard Model, with possible implications for the origin of the baryon asymmetry of the universe - the question of what happened to all the antimatter that must have been produced in the Big Bang. The experiment will be carried out by an international collaboration and will require some four years of running time. As possibly the sole hadron experiment in progress at Fermilab during that time, it will play an important role in maintaining a broad particle physics program at Fermilab and in the U.S. It will thus help us to continue attracting creative and capable young people into science and technology, and introducing them to the important technologies of accelerators, detectors, and data acquisition and analysis - key roles in society that accelerator-based particle physics has historically played.

  19. The Antiproton Accumulator (AA)

    CERN Multimedia

    1980-01-01

    Section 06 - 08*) of the AA where the dispersion (and hence the horizontal beam size) is large. One can distinguish (left to right): A vacuum-tank, two bending magnets (BST06 and BST07 in blue) with a quadrupole (QDN07, in red) in between, another vacuum-tank, a wide quadrupole (QFW08) and a further tank . The tanks are covered with heating tape for bake-out. The tank left of BST06 contained the stack core pickup for stochastic cooling (see 7906193, 7906190, 8005051), the two other tanks served mainly as vacuum chambers in the region where the beam was large. Peter Zettwoch works on BST06. *) see: H. Koziol, Antiproton Accumulator Parameter List, PS/AA/Note 84-2 (1984)

  20. A Measurement of Z Boson Production and Rapidity Distribution in Proton-Antiproton Collisions at √s = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Robson, Aidan [Univ. of Oxford (United Kingdom). Particle Physics Dept.

    2004-12-25

    High-precision measurements are made of Z boson production in proton-antiproton collisions at √s = 1.96 TeV recorded by the Collider Detector at Fermilab, using the electron decay channel. The cross-section times branching ratio is measured to be σZ · Br(Z → e+e-) = (255.7 ± 2.4stat ± 5.2sys ± 15.2lum)pb in a dataset of 194 pb-1 collected between March 2002 and June 2003. This agrees well with theoretical predictions. The cross-section for W boson production in the electron channel has also been measured in the subset of this dataset of 72 pb-1 collected up until January 2003. Using this smaller dataset the ratio of cross-sections is determined to be R ≡ σW · Br(W → eν)/σZ · Br(Z → ee) = 10.82 ± 0.18stat ± 0.16sys. Combining these results with measurements made in the muon channel gives R = 10.92 ± 0.15stat ± 0.14sys (e + μ channels), from which the branching ratio of the W to electrons and muons, and the total width of the W, have been extracted: Br(W → lν) = 0.1089 ± 0.0022 (l = e,μ); Γ(W) = 2078.8 ± 41.4 MeV, which are in good agreement with the Standard Model values and with other measurements. The CKM quark mixing matrix element |Vcs| has been extracted: |Vcs| = 0.967 ± 0.030. The rapidity distribution dσ/dy for Z → ee has also been measured over close to the full kinematic range using 194 pb-1 of data, and is found to be in good agreement with the NNLO prediction.

  1. The discovery of the antiproton

    International Nuclear Information System (INIS)

    Chamberlain, Owen

    1989-01-01

    A number of groups of particle physicists competed to provide track evidence of the existence of Dirac's postulated antiproton in the mid-1950s. The work of the several teams is described briefly. The author describes the work of his own group on the Bevatron in more detail, and how they finally observed the antiproton. The article finishes with an assessment of the importance of this discovery. (UK)

  2. Measurement of top anti-top cross section in proton - anti-proton collider at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Mal, Prolay Kumar [Tata Inst. of Fundamental Research, Bombay (India)

    2005-04-01

    Discovery of the top quark in 1995 at the Fermilab Tevatron collider concluded a long search following the 1977 discovery of bottom (b) quark [1] and represents another triumph of the Standard Model (SM) of elementary particles. Top quark is one of the fundamental fermions in the Standard Model of electroweak interactions and is the weak-isospin partner of the bottom quark. A precise measurement of top pair production cross-section would be a test of Quantum Chromodynamics (QCD) prediction. Presently, Tevatron is the world's highest energy collider where protons (p) and anti-protons ($\\bar{p}$) collide at a centre of mass energy √s of 1.96 TeV. At Tevatron top (t) and anti-top ($\\bar{t}$) quarks are predominantly pair produced through strong interactions--quark annihilation (≅ 85%) and gluon fusion (≅ 15%). Due to the large mass of top quark, t or $\\bar{t}$ decays (~ 10-25 sec) before hadronization and in SM framework, it decays to a W boson and a b quark with ~ 100% branching ratio (BR). The subsequent decay of W boson determines the major signatures of t$\\bar{t}$ decay. If both W bosons (coming from t and $\\bar{t}$ decays) decay into leptons (viz., eve, μvμ or τcτ) the corresponding t$\\bar{t}$ decay is called dileptonic decay. Of all dileptonic decay modes of t$\\bar{t}$, the t$\\bar{t}$ → WWb$\\bar{b}$ → eveμvμb$\\bar{b}$ (eμ channel) decay mode has the smallest background contamination from Z0 production or Drell-Yan process; simultaneously, it has the highest BR (~ 3.16%) [2] amongst all dileptonic decay modes of t$\\bar{t}$. During Run I (1992-1996) of Tevatron, three eμ candidate events were detected by D0 experiment, out of 80 candidate events (inclusive of all decay modes of t$\\bar{t}$). Due to the rarity of the t$\\bar{t}$ events, the measured cross-section has large uncertainty in its value (viz., 5.69 ± 1.21(stat) ± 1.04(sys) pb {at} √s = 1

  3. Depth-Dose and LET Distributions of Antiproton Beams in Various Target Materials

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Olsen, Sune; Petersen, Jørgen B.B.

    Purpose  Radiotherapy with antiprotons is still being investigated as a possible new beam modality. Antiprotons behave much like protons until they come to rest, where they will annihilate with a target nucleus, thereby releasing additional energy. This can potentially lead to a favourable  depth......-dose distributions and an increased biological effect in the target region from the production of secondary nuclear fragments with increased LET. Earlier it has been speculated how the target material will affect the depth-dose curve of antiprotons and secondary particle production. Intuitively, the presence...... of elements with higher Z, may lead to heavier fragments, which in turn may increase the LET and be beneficial in radiotherapy context. Also, it was speculated whether the addition of elements with high thermal neutron cross section to the target material may or may not boost the locally deposited energy from...

  4. Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon A Search for TeV-Energy Antiprotons

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, G J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kraber, M; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2005-01-01

    The shadowing of high-energy cosmic rays by the Moon has been observed with a significance of 9.4 standard deviations with the L3+C muon spectrometer at CERN. A significant effect of the Earth magnetic field is observed. Since no event deficit on the east side of the Moon has been observed, an upper limit at 90% confidence level on the antiproton to proton ratio of 0.11 is obtained for primary energies around 1 TeV.

  5. Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon: A Search for TeV-Energy Antiprotons

    OpenAIRE

    Achard, P; Adriani, O; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P

    2004-01-01

    The shadowing of high-energy cosmic rays by the Moon has been observed with a significance of 9.4 standard deviations with the L3+C muon spectrometer at CERN. A significant effect of the Earth magnetic field is observed. Since no event deficit on the east side of the Moon has been observed, an upper limit at 90% confidence level on the antiproton to proton ratio of 0.11 is obtained for primary energies around 1 TeV.

  6. Polarization measurements in high energy elastic scattering of pions, kaons, protons and antiprotons on protons and comparison with Regge phenomenology

    International Nuclear Information System (INIS)

    Gaidot, A.; Bruneton, C.; Bystricky, J.; Cozzika, G.; Deregel, J.; Ducros, Y.; Khantine-Langlois, F.; Lehar, F.; Lesquen, A. de; Merlo, J.P.; Miyashita, S.; Movchet, J.; Pierrard, J.; Raoul, J.C.; Van Rossum, L.; Kanavets, V.P.

    1975-01-01

    The polarization parameter P has been measured for elastic scattering on polarized protons, of π - , K - and anti-p at 40GeV/c and of π + , K + and p at 45GeV/c. Four-momentum transfer ranges from -0.08 to -1.8(GeV/c) 2 for π - p and pp, and from -0.08 to -1.2(GeV/c) 2 for π + , K + or K - and anti-p [fr

  7. An international review of patient safety measures in radiotherapy practice

    International Nuclear Information System (INIS)

    Shafiq, Jesmin; Barton, Michael; Noble, Douglas; Lemer, Claire; Donaldson, Liam J.

    2009-01-01

    Errors from radiotherapy machine or software malfunction usually are well documented as they affect hundreds of patients, whereas random errors affecting individual patients are more difficult to be discovered and prevented. Although major clinical radiotherapy incidents have been reported, many more have remained unrecognised or have not been reported. The literature in this field is limited as it is mostly published as a result of investigation of major errors. We present a review of radiotherapy incidents internationally with the aim of identifying the domains where most errors occur through extensive review and synthesis of published reports, unpublished 'Grey literature' and departmental incident data. Our review of radiotherapy-related events in the last three decades (1976-2007) identified more than seven thousand (N = 7741) incidents and near misses. Three thousand one hundred and twenty-five incidents reported patient harm of variable intensity ranging from underdose increasing the risk of recurrence, to overdose causing toxicity, and even death for 1% (N = 38); 4616 events were near misses with no recognisable patient harm. Based on our review, a radiotherapy risk profile has been published by the WHO World Alliance for Patient Safety that highlights the role of communication, training and strict adherence to guidelines/protocols in improving the safety of radiotherapy process.

  8. Measurement of the Cross Section for Production of Prompt Diphoton in proton anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan-wen [Univ. of Geneva (Switzerland)

    2004-01-01

    This thesis presents the measurement of prompt diphoton production rate in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV using the upgraded Collider Detector at Fermilab (CDF II). This process deserves some attention for the following reasons. The H → γγ decay mode is an important channel for the Standard Model (SM) Higgs boson searches in the low mass region (MH < 130 GeV) at the forth coming LHC. In many models involving physics beyond the SM, cascade decays of heavy new particles generate a γγ signature. Some examples are supersymmetry with a light gravitino, radiative decays to a higgsino-LSP and models with large symmetry groups. The QCD production of prompt photon pairs with large invariant mass is the irreducible background to these searches. The rate is huge and requires to be quantitatively evaluated prior to any of the possible discoveries. In a hadronic collider environment such as LHC, prompt photon signals are contaminated by the production of neutral mesons which decay to multiple collinear photons. The experience of classifying background of neutral meson is very important. The process can be used to test the Next-to-Leading Order (NLO) calculation of Quantum Chromodynamics (QCD). The 4-momentum of particles in the di-photon final state can be precisely determined due to the fine energy resolution of the electromagnetic calorimeters. The imbalance in the transverse momentum of the two photons reflects the transverse motion of the colliding partons. At collider energies, most of the transverse momentum of the incoming partons can be attributed to multiple soft gluon emissions prior to the collision, of which the effect to di-photon production can be resummed by Collins-Soper-Sterman (CSS) formalism. The Tevatron data can be used to test the resummation formalisms. They have used 207 pb-1 of data collected by CDF II detector during the February 2002 to September 2003 running period to study the diphoton

  9. Antiproton tagging and vertex fitting in a Timepix3 detector

    CERN Document Server

    Aghion, S.; The AEGIS collaboration; Antonello, M.; Belov, A.; Bonomi, G.; Brusah, R. S.; Caccia, M.; Camper, A.; Caravita, R.; Castelli, F.; Cerchiari, G.; Comparat, D.; Consolati, G.; Demetrio, A.; Di Noto, L.; Doser, M.; Evans, C.; Fanì, M.; Ferragut, R.; Fesel, J.; Fontana, A.; Gerber, S.; Giammarchi, M.; Gligorova, A.; Guatieri, F.; Hackstock, P.; Haider, S.; Hinterberger, A.; Holmestad, H.; Kellerbauer, A.; Khalidova, O.; Krasnický, D.; Lagomarsino, V.; Lansonneur, P.; Lebrun, P.; Malbrunot, C.; Mariazzi, S.; Marton, J.; Matveev, V.; Müller, S. R.; Nebbia, G.; Nedelec, P.; Oberthaler, M.; Pacifico, N.; Pagano, D.; Penasa, L.; Petracek, V.; Prelz, F.; Prevedelli, M.; Rienaecker, B.; Robert, J.; Røhne, O. M.; Rotondi, A.; Sandaker, H.; Santoro, R.; Smestad, L.; Sorrentino, F.; Testera, G.; Tietje, I. C.; Widmann, E.; Yzombard, P.; Zimmer, C.; Zmeskal, J.; Zurlo, N.

    2018-01-01

    Studies of antimatter are important for understanding our universe at a fundamental level. There are still unsolved problems, such as the matter-antimatter asymmetry in the universe. The AEgIS experiment at CERN aims at measuring the gravitational fall of antihydrogen in order to determine the gravitational force on antimatter. The proposed method will make use of a position-sensitive detector to measure the annihilation point of antihydrogen. Such a detector must be able to tag the antiproton, measure its time of arrival and reconstruct its annihilation point with high precision in the vertical direction. This work explores a new method for tagging antiprotons and reconstructing their annihilation point. Antiprotons from the Antiproton Decelerator at CERN was used to obtain data on direct annihilations on the surface of a silicon pixel sensor with Timepix3 readout. These data were used to develop and verify a detector response model for annihilation of antiprotons in this detector. Using this model and the a...

  10. Jagiellonian University Drift Chamber Calibration and Track Reconstruction in the P349 Antiproton Polarization Experiment

    CERN Document Server

    Alfs, D; Moskal, P; Zieliński, M; Grzonka, D; Hauenstein, F; Kilian, K; Lersch, D; Ritman, J; Sefzick, T; Oelert, W; Diermaier, M; Widmann, E; Zmeskal, J; Wolke, M; Nadel-Turonski, P; Carmignotto, M; Horn, T; Mkrtchyan, H; Asaturyan, A; Mkrtchyan, A; Tadevosyan, V; Zhamkochyan, S; Malbrunot-Ettenauer, S; Eyrich, W; Zink, A

    2017-01-01

    The goal of the P349 experiment is to test whether the antiproton production process can be itself a source of antiproton polarization. In this article, we present the motivation and details of the performed measurement. We report on the status of the analysis focusing mainly on calibration of the drift chambers and 3d track reconstruction.

  11. In the steps of the antiproton

    CERN Multimedia

    Amsler, Claude

    2015-01-01

    Sixty years after the discovery of the antiproton at Berkeley, a look at some of the ways that studies with antiprotons at CERN have cast light on basic physics and, in particular, on fundamental symmetries.

  12. Phase measurement of cognitive impairment specific to radiotherapy.

    Science.gov (United States)

    Armstrong, Carol L; Shera, David M; Lustig, Robert A; Phillips, Peter C

    2012-07-01

    Memory impairment is an early-delayed effect of radiotherapy (RT). The prospective longitudinal measurement of the cognitive phase effects from RT was conducted on treated and untreated brain tumor patients. The study design investigated semantic vs. perceptual and visual vs. verbal memory to determine the most disease-specific measure of RT-related changes and understanding of the neurotoxicity from RT to the brain. Tests of memory that had previously shown RT-related phasic changes were compared with experimental tests of memory to test hypotheses about cognition targeted to the neural toxicity of RT. The results from 41 irradiated and 29 nonirradiated patients with low-grade, supratentorial tumors were analyzed. The methods controlled for comorbid white matter risk, recurrence, interval after treatment, and age (18-69 years). The effects were examined before RT and at three points after RT to 1 year using a mixed effects model that included interval, group, surgical status, medication use, practice, and individual random effects. Four new tests of memory and other candidate cognitive tests were investigated, and a post hoc analysis of a comprehensive battery of tests was performed to identify the cognitive processes most specific to RT. The RT effects on memory were identified in the treated group only; among the new tests of memory and the complete neurocognitive battery, the RT effects were significant only for delayed recall (p measurement that is brief but specific to neural mechanisms is effective and feasible for studies of RT damage. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Phase Measurement of Cognitive Impairment Specific to Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Carol L., E-mail: armstrongc@email.chop.edu [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Neuro-Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Shera, David M. [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Biostatistics and Epidemiology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Lustig, Robert A. [Department of Radiation Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States); Phillips, Peter C. [Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Department of Pediatrics, Division of Neurology and Oncology, University of Pennsylvania, School of Medicine, Philadelphia, Pennsylvania (United States)

    2012-07-01

    Purpose: Memory impairment is an early-delayed effect of radiotherapy (RT). The prospective longitudinal measurement of the cognitive phase effects from RT was conducted on treated and untreated brain tumor patients. The study design investigated semantic vs. perceptual and visual vs. verbal memory to determine the most disease-specific measure of RT-related changes and understanding of the neurotoxicity from RT to the brain. Methods and Materials: Tests of memory that had previously shown RT-related phasic changes were compared with experimental tests of memory to test hypotheses about cognition targeted to the neural toxicity of RT. The results from 41 irradiated and 29 nonirradiated patients with low-grade, supratentorial tumors were analyzed. The methods controlled for comorbid white matter risk, recurrence, interval after treatment, and age (18-69 years). The effects were examined before RT and at three points after RT to 1 year using a mixed effects model that included interval, group, surgical status, medication use, practice, and individual random effects. Four new tests of memory and other candidate cognitive tests were investigated, and a post hoc analysis of a comprehensive battery of tests was performed to identify the cognitive processes most specific to RT. Results: The RT effects on memory were identified in the treated group only; among the new tests of memory and the complete neurocognitive battery, the RT effects were significant only for delayed recall (p < 0.009) and interval to recognize (p < 0.002). Tumor location was not related to the treatment effect. Memory decline was specific to retrieval of semantic memories; a double dissociation of semantic from perceptual visual memory was demonstrated in the RT group. Conclusions: These results implicate memory dependent on the semantic cortex and the hippocampal memory system. A cognitive measurement that is brief but specific to neural mechanisms is effective and feasible for studies of RT damage.

  14. Phase Measurement of Cognitive Impairment Specific to Radiotherapy

    International Nuclear Information System (INIS)

    Armstrong, Carol L.; Shera, David M.; Lustig, Robert A.; Phillips, Peter C.

    2012-01-01

    Purpose: Memory impairment is an early-delayed effect of radiotherapy (RT). The prospective longitudinal measurement of the cognitive phase effects from RT was conducted on treated and untreated brain tumor patients. The study design investigated semantic vs. perceptual and visual vs. verbal memory to determine the most disease-specific measure of RT-related changes and understanding of the neurotoxicity from RT to the brain. Methods and Materials: Tests of memory that had previously shown RT-related phasic changes were compared with experimental tests of memory to test hypotheses about cognition targeted to the neural toxicity of RT. The results from 41 irradiated and 29 nonirradiated patients with low-grade, supratentorial tumors were analyzed. The methods controlled for comorbid white matter risk, recurrence, interval after treatment, and age (18–69 years). The effects were examined before RT and at three points after RT to 1 year using a mixed effects model that included interval, group, surgical status, medication use, practice, and individual random effects. Four new tests of memory and other candidate cognitive tests were investigated, and a post hoc analysis of a comprehensive battery of tests was performed to identify the cognitive processes most specific to RT. Results: The RT effects on memory were identified in the treated group only; among the new tests of memory and the complete neurocognitive battery, the RT effects were significant only for delayed recall (p < 0.009) and interval to recognize (p < 0.002). Tumor location was not related to the treatment effect. Memory decline was specific to retrieval of semantic memories; a double dissociation of semantic from perceptual visual memory was demonstrated in the RT group. Conclusions: These results implicate memory dependent on the semantic cortex and the hippocampal memory system. A cognitive measurement that is brief but specific to neural mechanisms is effective and feasible for studies of RT

  15. The Antiproton Accumulator (AA)

    CERN Multimedia

    1980-01-01

    A section of the AA where the dispersion (and hence the horizontal beam size) is large. One can distinguish (left to right): A large vacuum-tank, a quadrupole (QDN09*), a bending magnet (BST08), another vacuum-tank, a wide quadrupole (QFW08) and (in the background) a further bending magnet (BST08). The tanks are covered with heating tape for bake-out. The tank left of QDN09 contained the kickers for stochastic pre-cooling (see 790621, 8002234, 8002637X), the other one served mainly as vacuum chamber in the region where the beam was large. Peter Zettwoch works on QFW08. * see: H. Koziol, Antiproton Accumulator Parameter List, PS/AA/Note 84-2 (1984) See under 7911303, 7911597X, 8004261 and 8202324. For photos of the AA in different phases of completion (between 1979 and 1982) see: 7911303, 7911597X, 8004261, 8004608X, 8005563X, 8005565X, 8006716X, 8006722X, 8010939X, 8010941X, 8202324, 8202658X, 8203628X .

  16. Antiprotonic helium atomcules

    Directory of Open Access Journals (Sweden)

    Sauge Sébastien

    2012-10-01

    Full Text Available About 3% of antiprotons ( stopped in helium are long-lived with microsecond lifetimes, against picoseconds in all other materials. This unusual longevity has been ascribed to the trapping of on metastable bound states in He+ helium atom-molecules thus named atomcules. Apart from their unique dual structure investigated by laser spectroscopy – a near-circular quasi-classical Rydberg atom with l ~ n – 1 ~ 37 or a special diatomic molecule with a negatively charged nucleus in high rotational state with J = l – the chemical physics aspects of their interaction with other atoms or molecules constitute an interesting topic for molecular physics. While atomcules may resist to million collisions in helium, molecular contaminants such as H2 are likely to destroy them in a single one, down to very low temperatures. In the Born-Oppenheimer framework, we interpret the molecular interaction obtained by ab initio quantum chemical calculations in terms of classical reactive channels, with activation barriers accounting for the experiments carried out in He and H2. From classical trajectory Monte Carlo simulations, we show that the thermalization stage strongly quenches initial populations, thus reduced to a recovered 3 % trapping fraction. This work illustrates the pertinence of chemical physics concepts to the study of exotic processes involving antimatter. New insights into the physico-chemistry of cold interstellar radicals are anticipated.

  17. Improved Study of the Antiprotonic Helium Hyperfine Structure

    CERN Document Server

    Pask, T.; Dax, A.; Hayano, R.S.; Hori, M.; Horvath, D.; Juhasz, B.; Malbrunot, C.; Marton, J.; Ono, N.; Suzuki, K.; Zmeskal, J.; Widmann, E.

    2008-01-01

    We report the initial results from a systematic study of the hyperfine (HF) structure of antiprotonic helium (n,l) = (37,~35) carried out at the Antiproton Decelerator (AD) at CERN. We performed a laser-microwave-laser resonance spectroscopy using a continuous wave (cw) pulse-amplified laser system and microwave cavity to measure the HF transition frequencies. Improvements in the spectral linewidth and stability of our laser system have increased the precision of these measurements by a factor of five and reduced the line width by a factor of three compared to our previous results. A comparison of the experimentally measured transition frequencies with three body QED calculations can be used to determine the antiproton spin magnetic moment, leading towards a test of CPT invariance.

  18. A low-energy antiproton detector prototype for AFIS

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Lingxin; Greenwald, Daniel; Hahn, Alexander; Hauptmann, Philipp; Konorov, Igor; Losekamm, Martin; Paul, Stephan; Poeschl, Thomas; Renker, Dieter [Technische Universitaet Muenchen (Germany)

    2014-07-01

    Antiprotons are produced in interactions of primary cosmic rays with earth's exosphere, where a fraction of them will be confined in the geomagnetic field in the inner van Allen Belt. The antiproton-to-proton flux ratio predicted by theory is in good agreement with recent results from the South Atlantic Anomaly (SAA) published by the PAMELA collaboration. We have designed the AFIS (Antiproton Flux in Space) project in order to extend the measurable range of antiprotons towards the low-energy region. In scope of this project a small antiproton detector consisting of scintillating fibers and silicon photomultipliers is being developed as payload for a CubeSat traversing the SAA in Low Earth Orbit. For the proof of concept we have built a prototype called ''CubeZero'' which completed its first test using pion and proton beams at PSI, Switzerland. Our primary goal was to investigate on the performance of tracking and Bragg peak identification in hardware and software. Analysis of detector performance based on data taken during this beam test is presented in this talk.

  19. Measurement of the top quark pair production cross-section in dimuon final states in proton-antiproton collisions at 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Konrath, Jens Peter [Albert Ludwigs Univ., Freiburg (Germany)

    2008-10-24

    Particle physics deals with the fundamental building blocks of matter and their interactions. The vast number of subatomic particles can be reduced to twelve fundamental fermions, which interact by the exchange of spin-1 particles as described in the Standard Model (SM) of particle physics. The SM provides the best description of the subatomic world to date, despite the fact it does not include gravitation. Following the relation Λ = h/p, where h is Planck's constant, for the examination of physics at subatomic scales with size Λ probes with high momenta p are necessary. These high energies are accessible through particle colliders. Here, particles are accelerated and brought to collision at interaction points at which detectors are installed to record these particle collisions. Until the anticipated start-up of the Large Hadron Collider at CERN, the Tevatron collider at Fermilab near Chicago is the highest energy collider operating in the world, colliding protons and anti-protons at a center-of-mass energy of √s = 1.96 TeV. Its two interaction points are covered by the multi purpose particle detectors D0 and CDF. During the first data-taking period, known as Run I, the Tevatron operated at a center-of-mass energy of 1.8 TeV. This run period lasted from 1992 to 1996. During this period, the long-predicted top quark was discovered. From 1996 and 2001, the accelerator was upgraded to deliver higher instantaneous luminosities at its current center-of-mass energy. At the same time, the experiments were upgraded to take full advantage of the upgraded accelerator complex. The Tevatron is currently the only accelerator in the world with a sufficient energy to produce top quarks. Studying top quark production, decay and properties is an important part of the D0 and CDF physics programs. Because of its large mass, the top quark is a unique probe of the Standard Model, and an interesting environment to search for new physics. In this thesis, a measurement of the

  20. LEAR (Low Energy Antiproton Ring), general view.

    CERN Multimedia

    1990-01-01

    When the Antiproton Project was launched in the late 1970s, it was recognized that in addition to the primary purpose of high-energy proton-antiproton collisions in the SPS, there was interesting physics to be done with low-energy antiprotons. In 1982, LEAR was ready to receive antiprotons from the Antiproton Accumulator (AA), via the PS. A year later, delivery of antiprotons to the experiments began, at momenta as low as 100 MeV/c (kinetic energy 5.3 MeV), in an "Ultra-Slow Extraction" mode, dispensing some E9 antiprotons over times counted in hours. For such an achievement, stochastic and electron cooling had to be brought to high levels of perfection.

  1. Capture, Electron-Cooling and Compression of Antiprotons in a Large Penning-Trap for Physics Experiments with an Ultra-Low Energy Extracted Antiproton Beam

    CERN Multimedia

    2002-01-01

    % PS200 \\\\ \\\\The availability of ultra-low energy antiprotons is a crucial ingredient for the execution of the gravity measurements PS200. We have developed a method to provide such low energy antiprotons based on a large Penning trap (the PS200 catching trap). This system can accept a fast-extracted pulse from LEAR, reduce the energy of the antiprotons in the pulse from 5.9~MeV to several tens of kilovolts using a degrading foil, and then capture the antiprotons in a large Penning trap. These antiprotons are cooled by electrons previously admitted to the trap and are collected in a small region at the center of the trap. We have demonstrated our capability to capture up to 1~million antiprotons from LEAR in a single shot, electron cool these antiprotons, and transfer up to 95\\% of them into the inner, harmonic region. A storage time in excess of 1 hour was observed. These results have been obtained with the cryogenic trap vacuum coupled to a room temperature vacuum at about l0$ ^- ^{1} ^0 $ Torr, which is an...

  2. Antiproton Stråleterapi

    DEFF Research Database (Denmark)

    Bassler, Niels

    omkringliggende normalvæv sammenlignet med konventionel strålebehandling eller IMRT. Højenergetiske antiprotoner opfører sig som protoner under nedbremsning i vævet. Når antiprotonen er fuldstændigt nedbremset indfanges den af en kerne og annihilerer med en nucleon herfra. Derved frigives hvilemasseenergien på 2...

  3. Antiproton collisions with molecular hydrogen

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2008-01-01

    Theoretical antiproton and proton cross sections for ionization and excitation of hydrogen molecules as well as energy spectra of the ionized electrons were calculated in the impact-energy range from 8  to  4000  keV. The cross sections were computed with the close-coupling formulation of the sem...

  4. Radiotherapy Measurements with a Deoxyribonucleic Acid Doublestrand-Break Dosimeter

    Science.gov (United States)

    Obeidat, Mohammad Ali

    deoxyribonucleic acid remain attached to the beads and stay in the microtube (Fig. 4). Those beads were re-suspended with 50 microliter of phosphate-buffered saline again (called beads), then we placed both supernatant and beads in a reader microplate and we read the fluorescence signal for both with a fluorescence reader (BioTek Synergy 2). These beads and supernatant fluorescence signals are denoted by B and S, respectively. The relative amount of supernatant fluorescence counts is proportional to the probability of a double-strand-break. The probability of double-strand-break was calculated with the following equation: (S-BG)/(S+B-2BG) (1). where S was the supernatant fluorescence intensity (related to the number of double strands deoxyribonucleic acid with double-strand breaks), B was the re-suspended beads fluorescence intensity (related to the number of double strands deoxyribonucleic acid without double-strand breaks), and BG was the phosphate-buffered saline fluorescence intensity (related to the background signal). There are two advantages that this type of dosimeter has over the gel separation technique. First, it is important to irradiate deoxyribonucleic acid in a solution that has similar osmolarity and ion concentrations to that in a human, such as phosphate-buffered saline. A gel dosimeter would require a transfer to gel to separate deoxyribonucleic acid, whereas our dosimeter can be separated in this solution. Currently, we use pipettes to manually perform this separation, but this step could be automated. Second, the magnetic deoxyribonucleic acid separation technique is much faster than that for gel electrophoresis. Calibration of radiotherapy equipment isn't something that happens in national science laboratories, with only world-leading experts. This is something that happens locally at every cancer clinic, with physicists that do not have the luxury of focusing solely on this one measurement. For this reason, ease of use is critical for this type of technology

  5. Chemical reaction of protons with antiprotonic helium

    Science.gov (United States)

    Sakimoto, Kazuhiro

    2012-07-01

    Collisions of protons p with antiprotonic helium atoms p¯He+ (bound orbital states of an antiproton p¯ and a helium ion He+) are investigated from the viewpoint of chemical reaction. The p¯He+ atoms with high orbital angular momentum quantum numbers L>40 can be abundantly produced in the capture of p¯ by metastable helium atoms He(21,3S). Since such orbital states are considered to be practically stable despite having Auger decay channels (p¯He+→p¯He2++e), atomic and molecular collision processes involving p¯He+(L>40) are experimentally measurable. In this study, adiabatic electron energies in the Born-Oppenheimer approximation are calculated for the p+p¯He+ system. The p+p¯He+ dynamical calculations of p¯ exchange (→p¯p+He+) and dissociation (→p+p¯+He+) reactions on the ground-state adiabatic potential energy surface are carried out for various high orbital states of p¯He by using a classical trajectory Monte Carlo method. The reaction cross sections and the state distributions of antiprotonic hydrogen atoms (protonium) p¯p produced in the exchange reaction are presented. If the orbital shape of p¯He+ is near circular, the exchange reaction becomes inactive at low energies because the repulsive part of the interaction plays a critical role. In the p+p¯p system, however, the low-energy p¯ exchange reaction remains active for any type of the initial p¯p orbital motion.

  6. National Committee for the follow-up of measures for radiotherapy 2008-2011 - Final report

    International Nuclear Information System (INIS)

    Buzyn, A.; Grall, J.Y; Selleret, F.X.; Lacoste, A.C.; Maraninchi, D.; Harousseau, J-L.; Chauvet, B.; LE DU, D.; Saout, C.; Renody, N.; Depenweiller, C.; Goinere, R.

    2012-06-01

    As always more patients suffering from cancer are treated by radiotherapy, and as several over-irradiation events occurred in 2007, measures have been implemented to guarantee radiotherapy practice quality and safety. This document reports the work and actions performed by the national follow-up committee and its work groups to define, implement and follow-up these measures. They encompassed information actions towards patients, public, physicians and establishment managers, and new authorization measures. The committee also addressed radiotherapy professions involved in manipulation, dosimetry, as well as radio-physicists and radiotherapists. It introduced measures regarding vigilance in radiation, the improvement of quality and safety in radiation therapy centres, research and development, and the financing of these measures

  7. Laser Spectroscopy of Antiprotonic Helium Atoms

    CERN Multimedia

    2002-01-01

    %PS205 %title\\\\ \\\\Following the discovery of metastable antiprotonic helium atoms ($\\overline{p}He^{+} $) at KEK in 1991, systematic studies of their properties were made at LEAR from 1991 to 1996. In the first two years the lifetime of $\\overline{p}He^{+}$ in liquid and gaseous helium at various temperatures and pressures was measured and the effect of foreign gases on the lifetime of these atoms was investigated. Effects were also discovered which gave the antiproton a 14\\% longer lifetime in $^4$He than in $^3$He, and resulted in important differences in the shape of the annihilation time spectra in the two isotopes.\\\\ \\\\Since 1993 laser spectroscopy of the metastable $\\overline{p}He^{+}$ atoms became the main focus of PS205. Transitions were stimulated between metastable and non-metastable states of the $\\overline{p}He^{+}$ atom by firing a pulsed dye laser beam into the helium target every time an identified metastable atom was present (Figure 1). If the laser frequency matched the transition energy, the...

  8. Radiation studies in the antiproton source

    International Nuclear Information System (INIS)

    Church, M.

    1990-01-01

    Experiment E760 has a lead glass (Pb-G) calorimeter situated in the antiproton source tunnel in the accumulator ring at location A50. This location is exposed to radiation from several sources during antiproton stacking operations. A series of radiation studies has been performed over the last two years to determine the sources of this radiation and as a result, some shielding has been installed in the antiproton source in order to protect the lead glass from radiation damage

  9. PS, septum magnet for ejection of antiprotons

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    Antiprotons circulated in the PS in the sense opposite to that of the so far normal protons (or positive ions). A new ejection system with a new septum magnet was installed in straight section 58 for antiproton ejection, first towards the ISR and then to the principal customer, the SPS p-pbar Collider. Later on, when the PS delivered leptons for LEP, the antiproton ejection system was use for the ejection of electrons.

  10. Effects of impurity molecules on the lifetime of antiprotonic helium atoms

    CERN Document Server

    Juhász, B; Hayano, R S; Hori, Masaki; Horváth, D; Ishikawa, T; Torii, H A; Widmann, E; Yamaguchi, H; Yamazaki, T

    2004-01-01

    Quenching of metastable antiprotonic helium atoms in collisions with hydrogen and deuterium molecules has been studied using laser spectroscopy at CERN's antiproton decelerator. The temperature dependence of the quenching cross sections of the antiprotonic states (n, l) = (37, 34), (38, 35) and (38, 37) has been investigated and a deviation from the Arrhenius law was found at low temperatures. In case of the state (38, 37) with deuterium, detailed measurements revealed that the quenching cross section levels off at low temperatures indicating a strong quantum tunneling effect. (14 refs).

  11. Two photon laser spectroscopy of antiprotonic helium atoms at CERN’s AD

    CERN Document Server

    Hori, M

    2014-01-01

    The ASACUSA collaboration of CERN has carried out two-photon laser spectroscopy of antiprotonic helium atoms using counter-propagating ultraviolet laser beams. This excited some non-linear transitions of the antiproton at the wavelengths λ = 139.8–197.0 nm, in a way that reduced the thermal Doppler broadening of the observed resonances. The resulting narrow spectral lines allowed the measurement of three transition frequencies with fractional precisions of 2.3–5 parts in 109. By comparing these values with three-body QED calculations, the antiproton-to-electron mass ratio was derived as 1836.1526736(23). We briefly review these results.

  12. Galactic diffusion and the antiproton signal of supersymmetric dark matter

    CERN Document Server

    Chardonnet, P; Salati, Pierre; Taillet, R

    1996-01-01

    The leaky box model is now ruled out by measurements of a cosmic ray gradient throughout the galactic disk. It needs to be replaced by a more refined treatment which takes into account the diffusion of cosmic rays in the magnetic fields of the Galaxy. We have estimated the flux of antiprotons on the Earth in the framework of a two-zone diffusion model. Those species are created by the spallation reactions of high-energy nuclei with the interstellar gas. Another potential source of antiprotons is the annihilation of supersymmetric particles in the dark halo that surrounds our Galaxy. In this letter, we investigate both processes. Special emphasis is given to the antiproton signature of supersymmetric dark matter. The corresponding signal exceeds the conventional spallation flux below 300 MeV, a domain that will be thoroughly explored by the Antimatter Spectrometer experiment. The propagation of the antiprotons produced in the remote regions of the halo back to the Earth plays a crucial role. Depending on the e...

  13. Electrostatic ultra-low-energy antiproton recycling ring

    International Nuclear Information System (INIS)

    Siggel-King, M. R. F.; Papash, A.; Knudsen, H.; Holzscheiter, M.; Welsch, C. P.

    2011-01-01

    There is a strong need to push forward developments in the storage and control of ultra-low-energy antiproton beams to enable important scientific research. To this end, a small electrostatic ring, and associated electrostatic acceleration section, is being designed and developed by the QUASAR group. The ring will be placed on the MUSASHI beamline at the CERN-AD. It will serve as a prototype for the future ultra-low energy storage ring (USR), to be integrated at the facility for low-energy antiproton and ion research (FLAIR) and will enable various components of the USR to be tested and optimised. A reaction microscope will be integrated in the ring to enable partial ionisation cross section measurements to be made. This small recycler ring will be unique due to its combination of size, electrostatic nature and energy and type of circulating particles (ca 3–30 keV antiprotons). A short electrostatic accelerating section is also being developed, which will be placed between the beamline and the ring to accelerate the antiprotons from the trap extraction energy (typically 250 eV) to the final required (re-circulating) energy. The AD recycler project will be described, including ring design, accelerating injection section and the inclusion of a reaction microscope and the experiments it will enable.

  14. Primary populations of metastable antiprotonic $^{4}He$ and $^{3}He$ atoms

    CERN Document Server

    Hori, Masaki; Hayano, R S; Ishikawa, T; Sakuguchi, J; Tasaki, T; Widmann, E; Yamaguchi, H; Torii, H A; Juhász, B; Horváth, D; Yamazaki, T

    2002-01-01

    Initial population distributions of metastable antiprotonic **4He and **3He atoms over principal and angular momentum quantum numbers were investigated using laser spectroscopy. The total fractions of antiprotons captured into the metastable states of the atoms were deduced. Cascade calculations were performed using the measure populations to reproduce the delayed annihilation time spectrum. Results showed agreement between the simulated and measured spectra. (Edited abstract) 30 Refs.

  15. Design study of an Antiproton Collector for the Antiproton Accumulator (ACOL)

    International Nuclear Information System (INIS)

    Wilson, E.J.N.

    1983-01-01

    The Report gives a full description of an Antiproton Collector Ring which, placed around the existing Antiproton Accumulator at CERN, would enhance the antiproton flux available to both the SPS and LEAR by a factor of ten. The new ring and the focusing devices which precede it are designed to accept a much larger fraction of the antiproton production cone from the target. Each pulse of particles will be pre-cooled before being fed to the Antiproton Accumulator, where improved stochastic cooling systems will build up the stack. A full list of parameters is included. (orig.)

  16. Constraints on particle dark matter from cosmic-ray antiprotons

    International Nuclear Information System (INIS)

    Fornengo, N.; Vittino, A.; Maccione, L.

    2014-01-01

    Cosmic-ray antiprotons represent an important channel for dark matter indirect-detection studies. Current measurements of the antiproton flux at the top of the atmosphere and theoretical determinations of the secondary antiproton production in the Galaxy are in good agreement, with no manifest deviation which could point to an exotic contribution in this channel. Therefore, antiprotons can be used as a powerful tool for constraining particle dark matter properties. By using the spectrum of PAMELA data from 50 MV to 180 GV in rigidity, we derive bounds on the dark matter annihilation cross section (or decay rate, for decaying dark matter) for the whole spectrum of dark matter annihilation (decay) channels and under different hypotheses of cosmic-rays transport in the Galaxy and in the heliosphere. For typical models of galactic propagation, the constraints are strong, setting a lower bound on the dark matter mass of a ''thermal'' relic at about 40–80 GeV for hadronic annihilation channels. These bounds are enhanced to about 150 GeV on the dark matter mass, when large cosmic-rays confinement volumes in the Galaxy are considered, and are reduced to 3–4 GeV for annihilation to light quarks (no bound for heavy-quark production) when the confinement volume is small. Bounds for dark matter lighter than few tens of GeV are due to the low energy part of the PAMELA spectrum, an energy region where solar modulation is relevant: to this aim, we have implemented a detailed solution of the transport equation in the heliosphere, which allowed us not only to extend bounds to light dark matter, but also to determine the uncertainty on the constraints arising from solar modulation modelling. Finally, we estimate the impact of soon-to-come AMS-02 data on the antiproton constraints

  17. The Fermilab proton-antiproton collider upgrades

    International Nuclear Information System (INIS)

    Marriner, J.P.

    1996-10-01

    The plans for increases in the Tevatron proton-antiproton collider luminosity in the near future (Run II) and the more distant future (TeV33) are described. While there are many important issues, the fundamental requirement is to produce more antiprotons and to use them more efficiently

  18. PANDA : Strong Interaction Studies with Antiprotons

    NARCIS (Netherlands)

    Peters, Klaus; Schmitt, Lars; Stockmanns, Tobias; Messchendorp, Johan

    2017-01-01

    The Antiproton Anihilation in Darmstadt (PANDA) collaboration at the Facility for Antiproton and Ion Research (FAIR) is a cooperation of more than 400 scientists from 19 countries. FAIR will be an accelerator facility leading the European research in nuclear and hadron physics in the coming decade.

  19. Challenging the standard model by high-precision comparisons of the fundamental properties of protons and antiprotons.

    Science.gov (United States)

    Ulmer, S; Mooser, A; Nagahama, H; Sellner, S; Smorra, C

    2018-03-28

    The BASE collaboration investigates the fundamental properties of protons and antiprotons, such as charge-to-mass ratios and magnetic moments, using advanced cryogenic Penning trap systems. In recent years, we performed the most precise measurement of the magnetic moments of both the proton and the antiproton, and conducted the most precise comparison of the proton-to-antiproton charge-to-mass ratio. In addition, we have set the most stringent constraint on directly measured antiproton lifetime, based on a unique reservoir trap technique. Our matter/antimatter comparison experiments provide stringent tests of the fundamental charge-parity-time invariance, which is one of the fundamental symmetries of the standard model of particle physics. This article reviews the recent achievements of BASE and gives an outlook to our physics programme in the ELENA era.This article is part of the Theo Murphy meeting issue 'Antiproton physics in the ELENA era'. © 2018 The Authors.

  20. Laser-driven ultrafast antiproton beam

    Science.gov (United States)

    Li, Shun; Pei, Zhikun; Shen, Baifei; Xu, Jiancai; Zhang, Lingang; Zhang, Xiaomei; Xu, Tongjun; Yu, Yong; Bu, Zhigang

    2018-02-01

    Antiproton beam generation is investigated based on the ultra-intense femtosecond laser pulse by using two-dimensional particle-in-cell and Geant4 simulations. A high-flux proton beam with an energy of tens of GeV is generated in sequential radiation pressure and bubble regime and then shoots into a high-Z target for producing antiprotons. Both yield and energy of the antiproton beam increase almost linearly with the laser intensity. The generated antiproton beam has a short pulse duration of about 5 ps and its flux reaches 2 × 10 20 s - 1 at the laser intensity of 2.14 × 10 23 W / cm 2 . Compared to conventional methods, this new method based on the ultra-intense laser pulse is able to provide a compact, tunable, and ultrafast antiproton source, which is potentially useful for quark-gluon plasma study, all-optical antihydrogen generation, and so on.

  1. Comparing cystatin C changes as a measure of renal function before and after radiotherapy in patients with stomach cancer.

    Science.gov (United States)

    Rasouli, Hooshang Amir; Moghadam, Maryam Mirzaie; Tabatabaiefar, Morteza; Taslimi, Farnaz; Sheybani, Khosro Mojir; Alidoosti, Asadollah; Ameri, Ahmad; Fadavi, Pedram; Aref, Shahrzad

    2012-01-01

    The objective of this study was to determine and compare cystatin C changes before and after radiotherapy in patients with stomach cancer who were candidate for radiotherapy. This study was conducted as a prospective cohort one. Eighteen patients with definite diagnosis of stomach cancer under treatment by radiotherapy who presented to Radiotherapy-Oncology Center of Imam Hossein Hospital, Tehran-Iran, and the treatment in all cases was simultaneous chemoradiation with Xeloda were included. In all patients before radiotherapy and after radiotherapy serum creatinine (Cr) and cystatin C were measured simultaneously. Mean cystatin level before treatment (1.2 ± 0.4) was significantly lower than that of post-treatment (1.6 ± 0.36), (P=0.001). Serum Cr level before treatment was 1.15 ± 0.33 and after radiotherapy was 1.08 ± 0.24 and did not show significant difference. Glomerular filtration rate (GFR) of the patients before radiotherapy was -46.8 ± 21.0 and after radiotherapy was 43.8 ± 15.8 that did not have significant difference (P=0.146) and also blood urea nitrogen (BUN) before radiotherapy was 20.72 ± 3.7 and 20 ± 6.38 after radiotherapy that did not have significant difference (P=0.6). Comparison of the cystatin C difference with total radiation dose of the kidneys that are put in three dose groups in radiotherapy field had association that in dose of less that 18 gray (Gy) the cystatin C change showed significant and positive association (P=0.027; r=0.52) and about 18-24 Gy the cystatin C difference showed significant and negative association (P=0.023, r=-0.53). It seems that for evaluating the renal function, serum cystatin C measurement is preferable than serum Cr. level.

  2. Comparing Cystatin C Changes as a Measure of Renal Function Before and After Radiotherapy in Patients with Stomach Cancer

    Directory of Open Access Journals (Sweden)

    Ahmad Ameri

    2012-01-01

    Full Text Available The objective of this study was to determine and compare Cystatin C changes before and after radiotherapy in patients with stomach cancer who were candidate for radiotherapy. This study was conducted as a prospective cohort one. Eighteen patients with definite diagnosis of stomach cancer under treatment by radiotherapy who presented to Radiotherapy-Oncology Center of Imam Hossein Hospital, Tehran-Iran, and the treatment in all cases was simultaneous chemoradiation with Xeloda were included. In all patients before radiotherapy and after radiotherapy serum creatinine (Cr and Cystatin C were measured simultaneously. Mean cystatin level before treatment (1.2±0.4 was significantly lower than that of post-treatment (1.6±0.36, (P=0.001. Serum Cr level before treatment was 1.15±0.33 and after radiotherapy was 1.08±0.24 and did not show significant difference. Glomerular filtration rate (GFR of the patients before radiotherapy was -46.8 ± 21.0 and after radiotherapy was 43.8±15.8 that did not have significant difference (P=0.146 and also blood urea nitrogen (BUN before radiotherapy was 20.72±3.7 and 20 ± 6.38 after radiotherapy that did not have significant difference (P=0.6. Comparison of the Cystatin C difference with total radiation dose of the kidneys that are put in three dose groups in radiotherapy field had association that in dose of less that 18 gray (Gy the Cystatin C change showed significant and positive association (P=0.027; r=0.52 and about 18-24 Gy the Cystatin C difference showed significant and negative association (P=0.023, r=-0.53. It seems that for evaluating the renal function, serum Cystatin C measurement is preferable than serum Cr. level.

  3. The proton-antiproton collider

    International Nuclear Information System (INIS)

    Evans, L.

    1988-01-01

    The subject of this lecture is the CERN Proton-Antiproton (panti p) Collider, in which John Adams was intimately involved at the design, development, and construction stages. Its history is traced from the original proposal in 1966, to the first panti p collisions in the Super Proton Synchrotron (SPS) in 1981, and to the present time with drastically improved performance. This project led to the discovery of the intermediate vector boson in 1983 and produced one of the most exciting and productive physics periods in CERN's history. (orig.)

  4. Medium-Energy Antiproton Physics with the Antiproton Annihilation Spectrometer (TApAS*) at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Bartoszek, Larry [Bartoszek Engineering, Aurora, IL (United States); Piacentino, Giovanni M. [Univ. of Cassino (Italy); Phillips, Thomas J. [Duke Univ., Durham, NC (United States); Apollinari, Giorgio [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Broemmelsiek, Daniel R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Brown, Charles N. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Christian, David C. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Derwent, Paul; Gollwitzer, Keith [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Hahn, Alan [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Papadimitriou, Vaia [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Stancari, Giulio [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Stancari, Michelle [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Stefanski, Ray [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Volk, James T. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Werkema, Steven [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Wester, Willam [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); White, Herman B. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Yeh, G. P. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Baldini, Wander [Istituto Nazionale di Fisica Nucleare (INFN), Ferrara (Italy); Jackson, Gerald P. [Hbar Technologies, Chicago, IL (United States); Lau, Kwong [Univ. of Houston, TX (United States); Kaplan, Daniel M. [Illinois Inst. of Technology, Chicago, IL (United States); Torun, Yagmur [Illinois Inst. of Technology, Chicago, IL (United States); White, Christopher G. [Illinois Inst. of Technology, Chicago, IL (United States). et al.

    2008-01-01

    We propose to assemble a cost-effective, yet powerful, solenoidal magnetic spectrometer for antiproton-annihilation events and use it at the Fermilab Antiproton Accumulator to measure the charm production cross section, study rare hyperon decays, search for hyperon CP asymmetry, and precisely measure the properties of several charmonium and nearby states. Should the charm production cross section be as large as some have proposed, we will also be able to measure D{sup 0}-{bar D}{sup 0} mixing with high precision and discover (or sensitively limit) charm CP violation. The experiment will be carried out by an international collaboration, with installation occurring during the accelerator downtime following the completion of the Tevatron run, and with funding largely from university research grants. The experiment will require some four years of running time. As possibly the sole hadron experiment in progress at Fermilab during that time, it will play an important role in maintaining a broad particle-physics program at Fermilab and in the U.S.

  5. X-rays from anti-protonic hydrogen and deuterium

    Energy Technology Data Exchange (ETDEWEB)

    Gorringe, T.P.; Davies, J.D.; Lowe, J.; Nelson, J.M.; Playfer, S.M.; Pyle, G.J.; Squier, G.T.A.; Baker, C.A.; Batty, C.J.; Clark, S.A.; Kilvington, A.I.; Moir, J.; Sakamoto, S.; Welsh, R.E.; Winter, R.G.; Lingeman, E.W.A.

    1985-11-07

    Antiprotons from the LEAR facility at CERN were stopped in targets of gaseous H/sub 2/ or D/sub 2/. Yields of L X-rays were measured. K-series from anti p-p atoms were observed. The measured shift and width for the 1s level are ..delta..Esub(1s)=-0.73+-0.15 keV and GAMMAsub(1s)=0.85+-0.39 keV. (orig.).

  6. Neutrons from Antiproton Irradiation

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael; Petersen, Jørgen B.B.

    the volume targeted for irradiation. A major part of this peripheral dose arise from neutrons, which in particular are problematic due to their high RBE for secondary cancer incidence. We have measured the fast and thermal neutron spectrum in different geometrical configurations in order to experimentally...

  7. Relative Biological Effect of Antiprotons

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael

    purpose/objective The AD-4/ACE collaboration has recently performed experiments to directly measure the RBE of antiprotons. Antiprotons have very similar stopping power compared to protons, but when they come to rest, antiprotons will annihilate on a target nucleus and thereby release almost 2 Ge......V of energy. About 30 MeV of this energy is deposited in the vicinity of the Bragg-peak, thereby significantly enhancing it. It is furthermore expected that this additional energy is deposited by radiation which carries a high-LET component. This will have a significant influence on the radiobiological...... nuclear research facility CERN. A beam of 126 MeV antiprotons, corresponding to about 12 cm range in water, was spread out to a SOBP with a width of 1 cm. Dosimetry experiments were carried out with ionization chambers, alanine pellets and radiochromic film, and the results were used for benchmarking...

  8. High-precision spectroscopy of antiprotonic helium-first results from the AD of CERN

    CERN Document Server

    Widmann, E

    2001-01-01

    New results of the laser and microwave spectroscopy of antiprotonic helium "atomcules" obtained in the first year of operation of the Antiproton Decelerator (AD) facility of CERN are presented. They include the discovery of three new resonant transitions and the determination of the zero-density wavelength of six transitions with an accuracy of 130 ppb in the best case. Auger rates of those states were also determined, and two of them were found to be several orders of magnitude larger than expected from a simple estimate based on the multipolarity Delta l, i.e., the jump in angular momentum required for the antiproton to reach the next lower-lying state of ionized pHe /sup ++/. Furthermore, a first signal of a two-laser microwave triple resonance to measure the hyperfine splitting in antiprotonic helium was observed. (39 refs).

  9. Quantitative assessment of skin erythema due to radiotherapy--evaluation of different measurements

    International Nuclear Information System (INIS)

    Wengstroem, Yvonne; Forsberg, Christina; Naeslund, Ingemar; Bergh, Jonas

    2004-01-01

    Background and purpose: Visual assessment is the most common clinical investigation of skin reactions in radiotherapy. Due to the unquantitative and subjective nature of this method additional non-invasive methods are needed for more accurate evaluation of the visible acute adverse skin reactions due to radiotherapy. The purpose of this study was to evaluate a new objective measure with regard to reliability and validity and compare it with an established objective measure and a visual assessment. Patients and methods: A sample of 53 consecutive patients commencing curative tangential radiation therapy to the breast parenchyma were included in the study. The skin area of the treated breast was divided into five sections and assessed individually at 0, 24 and 50 Gy. The RTOG scoring system was used for the visual assessment of the skin reactions. The first objective measure included reflectance spectrometry (DermaSpectrometer) measures at fixed points within the treatment area. For the second objective measure digital images (Camera) were taken with a system using a digital camera and software. The images were analyzed using the Adobe Photoshop 5.0 software program. Results: The results provided significant evidence of the test-retest reliability of the camera. The correlation between the objective measures proved to be significant as the treatment progressed. Conclusions: The results suggest that the camera may be used in a reliable and valid way to measure skin erythema due to radiotherapy

  10. The Production Cross Sections Of The Weak Vector Bosons In Proton-antiproton Collisions At Center Of Mass Energy = 1.96 Tev And A Measurement Of The W Boson Decay Width

    CERN Document Server

    Varganov, A V

    2004-01-01

    We present an analysis of data from proton-antiproton collisions at 1.96 TeV at the Fermilab Tevatron. The data represent about 194 pb-1 collected by the Collider Detector at Fermilab (CDF) during 2002--2003. A new measurement is made of the ratio of inclusive W and Z boson cross sections using high-PT muons in the CDF detector. Our measurement yields: s pp→WBR W→mn=2.786+0.060 -0.054syst +/-0.012stat +/-0.166lum nb, sp p→ZBRZ→m +m-=253.1+7 .1-6.2syst +/-4.2stat+/- 15.2lum pb, R≡s pp&d1;→WBR W→mn spp&d1;→ ZBRZ→m+ m-=11.02+/- 0.14syst+/-0 .18stat. A comparison with theoretical predictions allows an indirect value for the W leptonic branching ratio: BRW→mn =11.01+/-0.14syst +/-0.18stat+/- 0.05ext %. Using the Standard Model prediction for GW→ℓn we extract the total width of the W boson: GW=2056+/- 26syst+/-34 stat+/-10 extMeV. We discuss the significance of the ratio measurement in light of existing information on W and Z production and decay.

  11. How should we measure and report radiotherapy-induced xerostomia?

    NARCIS (Netherlands)

    Eisbruch, Avraham; Rhodus, Nelson; Rosenthal, David; Murphy, Barbara; Rasch, Coen; Sonis, Stephen; Scarantino, Charles; Brizel, David

    2003-01-01

    Xerostomia is commonly measured and graded using objective measures of major salivary gland output and observer-rated toxicity grading. The separation between the different grades is somewhat ambiguous in the current toxicity grading systems. We propose a new grading system based primarily on the

  12. Centrality dependence of proton and antiproton spectra in Pb+Pb collisions at 40A GeV and 158A GeV measured at the CERN SPS

    CERN Document Server

    Anticic, T.; Barna, D.; Bartke, J.; Beck, H.; Betev, L.; Bialkowska, H.; Blume, C.; Bogusz, M.; Boimska, B.; Book, J.; Botje, M.; Buncic, P.; Cetner, T.; Christakoglou, P.; Chung, P.; Chvala, O.; Cramer, J.G.; Eckardt, V.; Fodor, Z.; Foka, P.; Gazdzicki, M.; Grebieszkow, K.; Hohne, C.; Kadija, K.; Karev, A.; Kolesnikov, V.I.; Kowalski, M.; Kresan, D.; Laszlo, A.; Lacey, R.; van Leeuwen, M.; Mackowiak, M.; Makariev, M.; Malakhov, A.I.; Mateev, M.; Melkumov, G.L.; Mitrovski, M.; Mrowczynski, S.; Nicolic, V.; Palla, G.; Panagiotou, A.D.; Peryt, W.; Pluta, J.; Prindle, D.; Puhlhofer, F.; Renfordt, R.; Roland, C.; Roland, G.; Rybczynski, M.; Rybicki, A.; Sandoval, A.; Schmitz, N.; Schuster, T.; Seyboth, P.; Sikler, F.; Skrzypczak, E.; Slodkowski, M.; Stefanek, G.; Stock, R.; Strobele, H.; Susa, T.; Szuba, M.; Utvic, M.; Varga, D.; Vassiliou, M.; Veres, G.I.; Vesztergombi, G.; Vranic, D.; Wlodarczyk, Z.; Wojtaszek-Szwarc, A.

    2011-01-01

    The yields of (anti-)protons were measured by the NA49 Collaboration in centrality selected Pb+Pb collisions at 40A GeV and 158A GeV. Particle identification was obtained in the laboratory momentum range from 5 to 63 GeV/c by the measurement of the energy loss dE/dx in the TPC detector gas. The corresponding rapidity coverage extends 1.6 units from mid-rapidity into the forward hemisphere. Transverse mass spectra, the rapidity dependences of the average transverse mass, and rapidity density distributions were studied as a function of collision centrality. The values of the average transverse mass as well as the midrapidity yields of protons when normalized to the number of wounded nucleons show only modest centrality dependences. In contrast, the shape of the rapidity distribution changes significantly with collision centrality, especially at 40A GeV. The experimental results are compared to calculations of the HSD and UrQMD transport models.

  13. P-986 Letter of Intent: Medium-Energy Antiproton Physics at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David M. [Carleton Univ., Ottawa, ON (Canada); Phillips, Thomas J. [Duke Univ., Durham, NC (United States); Apollinari, Giorgio [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Broemmelsiek, Daniel R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Brown, Charles N. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Christian, David C. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Derwent, Paul [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Gollwitzer, Keith [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Hahn, Alan [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Papadimitriou, Vaia [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Stefanski, Ray [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Werkema, Steven [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); White, Herman B. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Baldini, Wander [Istituto Nazionale di Fisica Nucleare (INFN), Ferrara (Italy); Stancari, Giulio [Istituto Nazionale di Fisica Nucleare (INFN), Ferrara (Italy); Stancari, Michelle [Istituto Nazionale di Fisica Nucleare (INFN), Ferrara (Italy); Jackson, Gerald P. [Hbar Technologies, Chicago, IL (United States); Kaplan, Daniel M. [Illinois Inst. of Technology, Chicago, IL (United States); Torun, Yagmur [Illinois Inst. of Technology, Chicago, IL (United States); White, Christopher G. [Illinois Inst. of Technology, Chicago, IL (United States); Park, HyangKyu [HyungPook National Univ., DaeGu (Korea, Republic of); Pedlar, Todd K. [Luther College, Decorah, IA (United States); Gustafson, H. Richard [Univ. of Michigan, Ann Arbor, MI (United States); Rosen, Jerome [Northwestern Univ., Evanston, IL (United States); Wayne, Mitchell [Univ. of Notre Dame, IN (United States); Chakravorty, Alak [St. Xavier Univ., Chicago, IL (United States); Dukes, E. Craig [Univ. of Virginia, Charlottesville, VA (United States)

    2009-02-05

    Fermilab has long had the world's most intense antiproton source. Despite this, the opportunities for medium-energy antiproton physics at Fermilab have been limited in the past and - with the antiproton source now exclusively dedicated to serving the needs of the Tevatron Collider - are currently nonexistent. The anticipated shutdown of the Tevatron in 2010 presents the opportunity for a world-leading medium-energy antiproton program. We summarize the current status of the Fermilab antiproton facility and review some physics topics for which the experiment we propose could make the world's best measurements. Among these, the ones with the clearest potential for high impact and visibility are in the area of charm mixing and CP violation. Continued running of the Antiproton Source following the shutdown of the Tevatron is thus one of the simplest ways that Fermilab can restore a degree of breadth to its future research program. The impact on the rest of the program will be minor. We request a small amount of effort over the coming months in order to assess these issues in more detail.

  14. Study of X-Ray and $\\gamma$-Ray Spectra from Antiprotonic Atoms at the Slowly Extracted Antiproton Beam of LEAR

    CERN Multimedia

    2002-01-01

    This experiment will study the X-ray spectra of antiprotonic atoms and the $\\gamma$ spectra of residual nuclei after the antiproton absorption. We intend to begin with measurements on selected isotopically pure targets. Strong interaction effects, the antiproton absorption and the atomic cascade are analysed through the measurement of energies, lineshapes, relative and absolute intensities of all observable lines. The experiments are continued to determine st in resolved fine structure levels and in different isotopes of the same element. Coincidence techniques may be applied. All components of the experimental set-up are already existing from previous experiments and we could begin the measurements with any slowly extracted beam of low energy at LEAR.

  15. GEM-based beam profile monitors for the antiproton decelerator

    CERN Document Server

    Duarte Pinto, S.; Ropelewski, L.; Spanggaard, J.; Tranquille, G.

    2012-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEGIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  16. Calculated LET-Spectrum of Antiprotons

    DEFF Research Database (Denmark)

    Bassler, Niels

    the resulting annihilation events occurring at the end of the antiproton particle tracks. It has so far been anticipated, that the radiobiology of antiproton beams is similar to that of protons in the entry region of the beam, but very different in the annihilation region, due to the expected high......-LET components resulting from the annihilation. Though, the calculations of dose-averaged LET in the entry region may suggest that the RBE of antiprotons in the plateau region could significantly differ from unity. Materials and Methods Monte Carlo simulations using FLUKA were performed for calculating...... of energy per nucleon. Results In the plateau region of the simulated antiproton beam we observe a dose-average LET of about 4 keV/µm which is very different from the expected 0.6 keV/µm of an equivalent primary proton beam. Even though the fluence of secondaries is a magnitude less than the fluence...

  17. Stochastic cooling and the accumulation of antiprotons

    CERN Document Server

    van der Meer, S

    1985-01-01

    The large project mentioned in the motivation of the 1985 Nobel award in physics includes, in addition to the experiments proper described by Carlo Rubbia, the complex machinery for colliding high-energy protons and antiprotons. Protons (ps) are accelerated to a momentum of 26 GeV/c in the Proton Synchrotron (PS) machine and are used to produce antiprotons (ps) in a copper target. The Antiproton Accumulator (AA) ring accepts a batch of these with momenta around 3.5 GeV/c every 2.4 seconds. After, typically, a day of accumulation, a large number of the accumulated ps ( approximately 10/sup 11/) are extracted from the AA. The author discusses stochastic cooling, a method used to accumulate the antiprotons. (23 refs).

  18. Antiproton chain of the FAIR storage rings

    International Nuclear Information System (INIS)

    Katayama, T; Kamerdzhiev, V; Lehrach, A; Maier, R; Prasuhn, D; Stassen, R; Stockhorst, H; Herfurth, F; Lestinsky, M; Litvinov, Yu A; Steck, M; Stöhlker, T

    2015-01-01

    In the Modularized Start Version of the Facility of Antiproton and Ion Research (FAIR) at Darmstadt Germany, the 3 GeV antiprotons are precooled in the collector ring and accumulated in the high energy storage ring (HESR). They are further accelerated to 14 GeV or decelerated to 1 GeV for the experiments with a high-density internal target. The powerful beam cooling devices, stochastic cooling and electron cooling will support the provision of a high-resolution antiproton beam. The other option of FAIR is to prepare the low energy, 300 keV antiproton beam connecting the existing storage rings ESR and CRYRING with HESR. Beam physics issues related with these concepts are described. (paper)

  19. Measurement of the absorbed dose in the very small size photon beams used in stereotactic radiotherapy

    International Nuclear Information System (INIS)

    Derreumaux, S.; Huet, C.; Robbes, I.; Trompier, F.; Boisserie, G.; Brunet, G.; Buchheit, I.; Sarrazin, T.; Chea, M.

    2008-01-01

    After the radiotherapy accident in Toulouse, the French authority of nuclear safety and the French agency of health products safety have asked the IR.S.N. to establish, together with experts from the French society of medical physics and the French society of radiotherapy and oncology, a national protocol on dose calibration for the very small beams used in stereotactic radiotherapy. The research and reflexions of the working group 'GT minifaisceaux ' set up by the I.R.S.N. are presented in this final report. A review of the international literature has been performed. A national survey has been done to know the present practices in the dosimetry of small fields. A campaign of measurements of the data needed to characterize the small beams for the different stereotactic systems has started, using different types of detectors acquired by the I.R.S.N.. In this report are presented a deep synthesis on the problems related to the dosimetry of small fields, the results of the national survey, the first results of the campaign of measurements and the recommendations of the GT. (authors)

  20. Antiprotons from dark matter annihilation in the Galaxy. Astrophysical uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Evoli, Carmelo [Chinese Academy of Sciences, Beijing (China). National Astronomical Observatories; Cholis, Ilias; Ullio, Piero [SISSA, Sezione di Trieste (Italy); INFN, Sezione di Trieste (Italy); Grasso, Dario [INFN, Sezione di Pisa (Italy); Maccione, Luca [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2011-08-15

    The latest years have seen steady progresses in WIMP dark matter (DM) searches, with hints of possible signals suggested by both direct and indirect detection experiments. Antiprotons can play a key role validating those interpretations since they are copiously produced by WIMP annihilations in the Galactic halo, and the secondary antiproton background produced by Cosmic Ray (CR) interactions is predicted with fair accuracy and matches the observed spectrum very well. Using the publicly available numerical DRAGON code, we reconsider antiprotons as a tool to constrain DM models discussing its power and limitations. We provide updated constraints on a wide class of annihilating DM models by comparing our predictions against the most up-to-date anti p measurements, taking also into account the latest spectral information on the p, He and other CR nuclei fluxes. Doing that, we probe carefully the uncertainties associated to both secondary and DM originated antiprotons, by using a variety of distinctively different assumptions for the propagation of CRs and for the DM distribution in the Galaxy. We find that the impact of the astrophysical uncertainties on constraining the DM properties can be much stronger, up to a factor of {proportional_to}50, than the one due to uncertainties on the DM distribution ({proportional_to}2-6). Remarkably, even reducing the uncertainties on the propagation parameters derived by local observables, non-local effects can still change DM model constraints even by 50%. Nevertheless, current anti p data place tight constraints on DM models, excluding some of those suggested in connection with indirect and direct searches. Finally we discuss the power of upcoming CR spectral data from the AMS-02 observatory to drastically reduce the uncertainties discussed in this paper and estimate the expected sensitivity of this instrument to some sets of DM models. (orig.)

  1. Antiproton-nucleus potentials from global fits to antiprotonic X-rays and radiochemical data

    Czech Academy of Sciences Publication Activity Database

    Friedman, E.; Gal, A.; Mareš, Jiří

    2005-01-01

    Roč. 761, 3/4 (2005), s. 283-295 ISSN 0375-9474 R&D Projects: GA AV ČR IAA1048305 Institutional research plan: CEZ:AV0Z10480505 Keywords : antiproton-nuclear interaction * RMF calculations * antiproton X-rays Subject RIV: BE - Theoretical Physics Impact factor: 1.950, year: 2005

  2. Interpretation of enhancements in the antiproton-neutron from antiproton-Deuteron annihilations

    International Nuclear Information System (INIS)

    Martin, L.J.; Mason, G.C.; Opat, G.I.

    1980-01-01

    Data are presented from a low energy antiproton-Deuteron experiment that show an enhancement near 1930 MeV in the antiproton-neutron mass spectrum. This, and other enhancements observed at nearby masses, may be interpreted in terms of a double-scattering effect

  3. Assessing measurement invariance of a health-related quality-of-life questionnaire in radiotherapy patients.

    Science.gov (United States)

    King-Kallimanis, Bellinda L; ter Hoeven, Claartje L; de Haes, Hanneke C; Smets, Ellen M; Koning, Caro C E; Oort, Frans J

    2012-12-01

    If the assumption of measurement invariance is not tested, we cannot be sure whether differences observed are due to true differences in health-related quality-of-life (HRQoL), or are measurement artifacts. We aim to investigate this assumption in a sample of heterogeneous cancer patients, focusing on whether age, sex, previous treatment for cancer, and information regarding treatment preferences result in biased HRQoL scores. 155 cancer patients who were about to begin their first session of radiotherapy were included. HRQoL was measured using the EORTC QLQ-C30. Structural equation modeling was applied to assess whether there was a violation of the assumption of invariance. A satisfactory single construct (Functioning HRQoL) measurement model was found and two violations of invariance were identified. Irrespective of patients' Functioning HRQoL, older patients reported worse physical functioning and patients who had received treatment prior to radiotherapy reported worse emotional functioning than we would otherwise expect. In the present study, accounting for measurement bias lead to a substantial improvement in the overall fit of the model. By ignoring the bias, we would have concluded that the model fit was unsatisfactory. The findings underline the importance of investigating measurement invariance in scales designed for heterogeneous samples.

  4. Antiprotons four times more effective than protons for cell irradiation

    CERN Multimedia

    2007-01-01

    "A pioneering experiment at CERN with potential future application in cancer therapy has produced its first results. Started in 2003, ACE (Antiproton Cell Experiment) is the first investigation of the biological effects of antiprotons." (1,5 page)

  5. Antiprotons four times more effective than protons for cell irradiation

    CERN Multimedia

    2006-01-01

    "A pioneering experiment at CERN with potential future application in cancer therapy has produced its first results. Started in 2003, ACE (Antiproton Cell Experiment) is the first investigation of the biological effects of antiprotons." (1,5 page)

  6. Measurement of radiation dose with BeO dosimeters using optically stimulated luminescence technique in radiotherapy applications.

    Science.gov (United States)

    Şahin, Serdar; Güneş Tanır, A; Meriç, Niyazi; Aydınkarahaliloğlu, Ercan

    2015-09-01

    The radiation dose delivered to the target by using different radiotherapy applications has been measured with the help of beryllium oxide (BeO) dosimeters to be placed inside the rando phantom. Three-Dimensional Conformal Radiotherapy (3DCRT), Intensity-Modulated Radiotherapy (IMRT) and Intensity-Modulated Arc Therapy (IMAT) have been used as radiotherapy application. Individual treatment plans have been made for the three radiotherapy applications of rando phantom. The section 4 on the phantom was selected as target and 200 cGy doses were delivered. After the dosimeters placed on section 4 (target) and the sections 2 and 6 (non-target) were irradiated, the result was read through the OSL technique on the Risø TL/OSL system. This procedure was repeated three times for each radiotherapy application. The doses delivered to the target and the non-target sections as a result of the 3DCRT, IMRT and IMAT plans were analyzed. The doses received by the target were measured as 204.71 cGy, 204.76 cGy and 205.65 cGy, respectively. The dose values obtained from treatment planning system (TPS) were compared to the dose values obtained using the OSL technique. It has been concluded that, the radiation dose can be measured with the OSL technique by using BeO dosimeters in medical practices. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Antiproton Trapping for Advanced Space Propulsion Applications

    Science.gov (United States)

    Smith, Gerald A.

    1998-01-01

    The Summary of Research parallels the Statement of Work (Appendix I) submitted with the proposal, and funded effective Feb. 1, 1997 for one year. A proposal was submitted to CERN in October, 1996 to carry out an experiment on the synthesis and study of fundamental properties of atomic antihydrogen. Since confined atomic antihydrogen is potentially the most powerful and elegant source of propulsion energy known, its confinement and properties are of great interest to the space propulsion community. Appendix II includes an article published in the technical magazine Compressed Air, June 1997, which describes CERN antiproton facilities, and ATHENA. During the period of this grant, Prof. Michael Holzscheiter served as spokesman for ATHENA and, in collaboration with Prof. Gerald Smith, worked on the development of the antiproton confinement trap, which is an important part of the ATHENA experiment. Appendix III includes a progress report submitted to CERN on March 12, 1997 concerning development of the ATHENA detector. Section 4.1 reviews technical responsibilities within the ATHENA collaboration, including the Antiproton System, headed by Prof. Holzscheiter. The collaboration was advised (see Appendix IV) on June 13, 1997 that the CERN Research Board had approved ATHENA for operation at the new Antiproton Decelerator (AD), presently under construction. First antiproton beams are expected to be delivered to experiments in about one year. Progress toward assembly of the ATHENA detector and initial testing expected in 1999 has been excellent. Appendix V includes a copy of the minutes of the most recently documented collaboration meeting held at CERN of October 24, 1997, which provides more information on development of systems, including the antiproton trapping apparatus. On February 10, 1998 Prof. Smith gave a 3 hour lecture on the Physics of Antimatter, as part of the Physics for the Third Millennium Lecture Series held at MSFC. Included in Appendix VI are notes and

  8. The PANDA experiment: Antiproton physics at FAIR

    International Nuclear Information System (INIS)

    Montagna, P.

    2011-01-01

    The new Facility for Antiproton and Ion Research (FAIR), under construction at the GSI laboratory at Darmstadt, in a few years will make available, among different types of beams, even antiproton beams with unique features. Through a High Energy Storage Ring (HESR) for antiprotons, an antiproton beam will be available in a momentum range from 1.5 to 15 GeV/c, which will interact on a hydrogen target. The products of the interaction, including hadronic systems with strangeness and/or charm, will be detected with the PANDA magnetic spectrometer (antiProton ANnihilation at DArmstadt), and the spectroscopic analysis will allow a detailed investigation on a number of open problems of the hadronic physics, as the quark confinement, the existence of non-conventional meson states (so-called glueballs and hybrids), the structure of hadrons and of the strong interaction, with particular attention to charmonium spectroscopy. An overview of the scientific program of PANDA and the current status of the project will be presented.

  9. Polymer gel dosimetry for synchrotron stereotactic radiotherapy and iodine dose-enhancement measurements

    International Nuclear Information System (INIS)

    Boudou, C; Tropres, I; Rousseau, J; Lamalle, L; Adam, J F; Esteve, F; Elleaume, H

    2007-01-01

    Synchrotron stereotactic radiotherapy (SSR) is a radiotherapy technique that makes use of the interactions of monochromatic low energy x-rays with high atomic number (Z) elements. An important dose-enhancement can be obtained if the target volume has been loaded with a sufficient amount of a high-Z element, such as iodine. In this study, we compare experimental dose measurements, obtained with normoxic polymer gel (nPAG), with Monte Carlo computations. Gels were irradiated within an anthropomorphic head phantom and were read out by magnetic resonance imaging. The dose-enhancement due to the presence of iodine in the gel (iodine concentration: 5 and 10 mg ml -1 ) was measured at two radiation energies (35 and 80 keV) and was compared to the calculated factors. nPAG dosimetry was shown to be efficient for measuring the sharp dose gradients produced by SSR. The agreement between 3D gel dosimetry and calculated dose distributions was found to be within 4% of the dose difference criterion and a distance to agreement of 2.1 mm for 80% of the voxels. Polymer gel doped with iodine exhibited higher sensitivity, in good agreement with the calculated iodine-dose enhancement. We demonstrate in this preliminary study that iodine-doped nPAG could be used for measuring in situ dose distributions for iodine-enhanced SSR treatment

  10. Determination of the antiproton-to-electron mass ratio by precision laser spectroscopy of $\\overline{p}He^{+}$

    CERN Document Server

    Hori, M; Eades, John; Gomikawa, K; Hayano, R S; Ono, N; Pirkl, Werner; Widmann, E; Torii, H A; Juhász, B; Barna, D; Horváth, D

    2006-01-01

    A femtosecond optical frequency comb and continuous-wave pulse- amplified laser were used to measure 12 transition frequencies of antiprotonic helium to fractional precisions of (9-16) 10/sup -9lifetimes hitherto unaccessible to our precision laser spectroscopy method. Comparisons with three-body QED calculations yielded an antiproton-to-electron mass ratio of M/sub pmacron//m/sub e/=1836.152 674(5).

  11. Direct detection of antiprotons with the Timepix3 in a new electrostatic selection beamline

    Energy Technology Data Exchange (ETDEWEB)

    Pacifico, N., E-mail: nicola.pacifico@cern.ch [Institute of Physics and Technology, University of Bergen, Allgaten 55, 5007 Bergen (Norway); Aghion, S. [Politecnico of Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); INFN Milano, via Celoria 16, 20133 Milano (Italy); Alozy, J. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Amsler, C.; Ariga, A.; Ariga, T. [Laboratory for High Energy Physics, Albert Einstein Center for Fundamental Physics, University of Bern, 3012 Bern (Switzerland); Bonomi, G. [Department of Mechanical and Industrial Engineering, University of Brescia, via Branze 38, 25123 Brescia (Italy); INFN Pavia, via Bassi 6, 27100 Pavia (Italy); Bräunig, P. [Kirchhoff-Institute for Physics, Heidelberg University, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany); Bremer, J. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Brusa, R.S. [Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Trento (Italy); TIFPA/INFN Trento, via Sommarive 14, 38123 Povo, Trento (Italy); Cabaret, L. [Laboratory Aimé Cotton, University of Paris-Sud, ENS Cachan, CNRS, University Paris-Saclay, 91405 Orsay Cedex (France); Caccia, M. [INFN Milano, via Celoria 16, 20133 Milano (Italy); Department of Science, University of Insubria, Via Valleggio 11, 22100 Como (Italy); Campbell, M. [Physics Department, CERN, 1211 Geneva 23 (Switzerland); Caravita, R. [Department of Physics, University of Genova, via Dodecaneso 33, 16146 Genova (Italy); INFN Genova, via Dodecaneso 33, 16146 Genova (Italy); Castelli, F. [INFN Milano, via Celoria 16, 20133 Milano (Italy); Department of Physics, University of Milano, via Celoria 16, 20133 Milano (Italy); Cerchiari, G. [Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, 69117 Heidelberg (Germany); Chlouba, K. [Czech Technical University, Prague, Brehov 7, 11519 Prague 1 (Czech Republic); and others

    2016-09-21

    We present here the first results obtained employing the Timepix3 for the detection and tagging of annihilations of low energy antiprotons. The Timepix3 is a recently developed hybrid pixel detector with advanced Time-of-Arrival and Time-over-Threshold capabilities and has the potential of allowing precise kinetic energy measurements of low energy charged particles from their time of flight. The tagging of the characteristic antiproton annihilation signature, already studied by our group, is enabled by the high spatial and energy resolution of this detector. In this study we have used a new, dedicated, energy selection beamline (GRACE). The line is symbiotic to the AEgIS experiment at the CERN Antiproton Decelerator and is dedicated to detector tests and possibly antiproton physics experiments. We show how the high resolution of the Timepix3 on the Time-of-Arrival and Time-over-Threshold information allows for a precise 3D reconstruction of the annihilation prongs. The presented results point at the potential use of the Timepix3 in antimatter-research experiments where a precise and unambiguous tagging of antiproton annihilations is required.

  12. Evidence for the Stochastic Acceleration of Secondary Antiprotons by Supernova Remnants

    Energy Technology Data Exchange (ETDEWEB)

    Cholis, Ilias [Johns Hopkins U.; Hooper, Dan [Chicago U., KICP; Linden, Tim [Ohio State U.

    2017-01-16

    The antiproton-to-proton ratio in the cosmic-ray spectrum is a sensitive probe of new physics. Using recent measurements of the cosmic-ray antiproton and proton fluxes in the energy range of 1-1000 GeV, we study the contribution to the $\\bar{p}/p$ ratio from secondary antiprotons that are produced and subsequently accelerated within individual supernova remnants. We consider several well-motivated models for cosmic-ray propagation in the interstellar medium and marginalize our results over the uncertainties related to the antiproton production cross section and the time-, charge-, and energy-dependent effects of solar modulation. We find that the increase in the $\\bar{p}/p$ ratio observed at rigidities above $\\sim$ 100 GV cannot be accounted for within the context of conventional cosmic-ray propagation models, but is consistent with scenarios in which cosmic-ray antiprotons are produced and subsequently accelerated by shocks within a given supernova remnant. In light of this, the acceleration of secondary cosmic rays in supernova remnants is predicted to substantially contribute to the cosmic-ray positron spectrum, accounting for a significant fraction of the observed positron excess.

  13. K-shell ionization by antiprotons

    International Nuclear Information System (INIS)

    Mehler, G.; Mueller, B.; Greiner, W.; Soff, G.

    1987-01-01

    We present first calculations for the impact parameter dependence of K-shell ionization rates in anti pCu and in anti pAg collisions at various projectile energies. We show that the effect of the attractive Coulomb potential on the Rutherford trajectory and the anti-binding effect caused by the negative charge of the antiproton result in a considerable increase of the ionization probability. Total ionization cross-sections for proton and antiproton projectiles are compared with each other and with experimental ionization cross-sections for protons. (orig.)

  14. Collisions involving antiprotons and antihydrogen: an overview

    Science.gov (United States)

    Jonsell, S.

    2018-03-01

    I give an overview of experimental and theoretical results for antiproton and antihydrogen scattering with atoms and molecules (in particular H, He). At low energies (>1 keV) there are practically no experimental data available. Instead I compare the results from different theoretical calculations, of various degrees of sophistication. At energies up to a few tens of eV, I focus on simple approximations that give reasonably accurate results, as these allow quick estimates of collision rates without embarking on a research project. This article is part of the Theo Murphy meeting issue `Antiproton physics in the ELENA era'.

  15. The Antiproton and How It Was Discovered

    International Nuclear Information System (INIS)

    Eades, John

    2005-01-01

    The antiproton celebrates its 50th birthday this year. Although its existence had been suspected since the discovery of the positron in 1932, there was still doubt in some quarters that such a companion particle to the proton could exist. I will try to trace the scientific history of the antiproton from that time to the publication of the definitive paper by Chamberlain, Segre, Wiegand and Ypsilantis in November 1955, with a brief look at what happened next. The narrative will be supplemented with thoughts and opinions of some of the main actors, both at the time and in retrospect

  16. Small scale photon beams measurement and modeling for Intensity-modulated radiotherapy and radio-surgery

    International Nuclear Information System (INIS)

    Abdul Hadi, Talal

    2017-01-01

    The advanced techniques of radiotherapy use very small fields in case small tumors such as in the brain to irradiate precisely the lesion. This work concerns the measurement absorbed dose in small field of 0.5 x 0.5 cm 2 to 3 x 3 cm 2 . However, the measurement dose in small fields is characterized by high gradient dose and a leak of lateral electronic equilibrium. That requires use a detector having an adapted sensitive volume and adapted spatial resolution. The detectors marketed are not perfectly compatible with these conditions. Actually, there is no international methodological consensus, nor a metrological reference for measurement dose in small fields. The IAEA (International Atomic Energy Agency) protocol 398 used to calculate the absorbed dose at 10 cm x 10 cm is not suitable for small fields. In absence a referenced detector, the dosimetric data measurement is verified using a Gafchromic films due to its excellent spatial resolution. We measure using conventional detectors (ionization chambers and/or Gafchromic films) the leakage dose at a point outside of irradiated field. The dosimetric data such as output factor (OF), percentage depth dose (PDD) and off-axis ratio (OAR) were also carried out by the diode. The correlation between the on-axis dose and off-axis dose is the subject of our study. This study proposes an experimental method to calculate the on-axis dose in small field for stereotactic radiotherapy. The method is based on the out of field leakage measurement. This model can be used to validate dose and output factor measurement. The experimental validation of the present method was performed for square and rectangular fields with sizes ranging from 0.5 cm x 0.5 cm to 10 cm x 10 cm. (author) [fr

  17. The low-energy antiproton beam K4 at the KEK 12 GeV proton synchrotron

    International Nuclear Information System (INIS)

    Takasaki, M.; Kurokawa, S.; Kobayashi, M.; Taino, M.; Suzuki, Y.; Ishii, H.; Kato, Y.; Fujitani, T.; Nagashima, Y.; Omori, T.; Sugimoto, S.; Yamaguchi, Y.; Iwahori, J.; Yoshida, H.; Takeutchi, F.; Chiba, M.; Koike, M.

    1986-01-01

    The beam K4 is designed to transport high-intensity, high-purity antiprotons in the momentum range between 0.4 and 0.8 GeV/c. Antiprotons are separated from unwanted pions, muons, and electrons by double-stage mass separation. The solid-angle momentum acceptance of the beam is 34.1 msr % ΔP/P and the beam length is 28.5 m. The measured intensities of antiprotons at 450, 500, 580 and 650 MeV/c are 100, 210, 510 and 1100 per 10 12 ppp; the corresponding π - μ - e - /anti p ratios are 13.1, 7.7, 8.8 and 22.5, respectively. About 45% of the incomming antiprotons at 580 MeV stop or annihilate in flight in liquid hydrogen contained in a target cell with the dimension of 140 mm in diameter and 230 mm in length. (orig.)

  18. Direct measurement of the W boson decay width in proton-antiproton collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun-jie [Univ. of Maryland, College Park, MD (United States)

    2004-01-01

    This dissertation describes a direct measurement of the W boson total decay width, ΓW, using the D0 detector at the Fermilab Tevatron Collider. The measurement uses an integrated luminosity of 177.3 pb-1 data, collected during the 2002-2003 run. The width is determined from the shape of the transverse mass distribution, MT, by fitting the data in the tail region 100 < MT < 200 GeV. The result if ΓW = 2.011 ± 0.093(stat) ± 0.107(syst) GeV.

  19. A measurement of forward-backward charge asymmetry of electron-positron pairs in proton-antiproton collision at 1.8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Veramendi, Gregory Francisco [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    The authors present a measurement of the mass dependence of the forward-backward charge asymmetry for e+e- pairs resulting from γ*/Z decays with mass Mee > 40 GeV/c2. The Run II data sample consists of 72 pb-1 of data, which was collected by the CDF detector in $\\bar{p}$p collisions at √s = 1.96 TeV at the Fermilab Tevatron. The measurement is compared with predictions from the Standard Model.

  20. Measurement of the W + γ Production in Proton - Anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, Michael H. [Duke Univ., Durham, NC (United States)

    2004-01-01

    The authors present a measurement of the $\\bar{p}$p → Wγ + X → evγ + X production cross section using data form the Collider Detector at Fermilab. The p$\\bar{p}$ collisions were provided by the Tevatron Collider at a center of mass energy of 1.96 TeV. Electroweak theory includes the trilinear vector boson coupling, WWγ, which contributes to the evγ final state. The electron decay channel of the W provides a clean sample to study the production of diboson pairs. The measurement of the production cross section tests the structure of the non-Abelian character of Electroweak theory.

  1. The ASACUSA experiment at CERN's AD antiproton decelerator catches antiprotons in helium, where the antiprotons replace electrons, giving exotics atoms.

    CERN Multimedia

    Loïez, P

    2000-01-01

    Photo 03: Laser beams are prepared for shooting at antiprotonic helium atoms. Left to right: Masaki Hori (Tokyo University) and John Eades (CERN). Photo 01: Dye laser triggered by "YAG" laser. Photo 02: Masaki Hori adjusting optical system of laser beams.

  2. Study of Anti-Hydrogen and Plasma Physics 4.Observation of Antiproton Beams and Nonneutral Plasmas

    CERN Document Server

    Hori, Masaki; Fujiwara, Makoto; Kuroda, Naofumi

    2004-01-01

    Diagnostics of antiproton beams and nonneutral plasmas are described in this chapter. Parallel plate secondary electron emission detectors are used to non-destructively observe the beam position and intensity without loss. Plastic scintillation tracking detectors are useful in determining the position of annihilations of antiprotons in the trap. Three-dimensional imaging of antiprotons in a Penning trap is discussed. The unique capability of antimatter particle imaging has allowed the observation of the spatial distribution of particle loss in a trap. Radial loss is localized to small spots, strongly breaking the azimuthal symmetry expected for an ideal trap. By observing electrostatic eigen-modes of nonneutral plasmas trapped in the Multi-ring electrode trap, the non-destructive measurement of plasma parameters is performed.

  3. Measurement of the Proton-Antiproton Total Cross-Section at Center-of-Mass Energy of 1800-GeV

    Energy Technology Data Exchange (ETDEWEB)

    Avila, Carlos [Cornell U., LNS

    1997-05-01

    We have made a new measurement of the $P\\overline{P}$ total cross section at $\\sqrt{s}$=1800 GeV, using a luminosity independent method for the analysis. The value obtained is $\\sigma_T = 69.82 \\pm 2.44 mb$. Also we obtained the values of $\\sigma_{el} = 14.93 \\pm 1.03 mb$ and $\\sigma_{in} = 54.88 \\pm 1.43 mb$ for the total elastic and total inelastic cross sections respectively. To perform our measurement we used scintillation counters to detect inelastic events, and 4 scintillating fiber detectors installed inside the Tevatron vacuum to detect elastic events; the elastic detectors were read out with image intensifiers and ccds.

  4. Measurement of the polarization parameter for antiproton-proton annihilation into charged pion and kaon pairs between 1.0 and 2.2 GeV/c

    International Nuclear Information System (INIS)

    Carter, A.A.; Coupland, M.; Eisenhandler, E.; Franklyn, C.; Gibson, W.R.; Hojvat, C.; Jeremiah, D.R.; Kalmus, P.I.P.; Pritchard, T.W.; Atkinson, M.; Duke, P.J.; Williams, D.T.; Woulds, J.N.; Arnison, G.T.J.; Astbury, A.; Hill, D.; Jones, D.P.

    1977-01-01

    The polarization parameter P for the reactions anti pp→π - π + and anti pp→K - K + has been measured over essentially the full angular range at 11 laboratory momenta between 1.0 and 2.2 GeV/c, using a proton target polarized perpendicular to the scattering plane. The angles and momenta of both final state particles were determined from wire spark chambers, using the deflection caused by the polarized target magnet. Between 1000 and 5300 p - π + events, and 140 and 1300 K - K + events, were measured at each momentum. Differential cross sections for anti pp→π - π + were obtained. These are in excellent agreement with previous results. The polarization parameter for both channels is very close to +1 over much of the angular range. Legendre polynomial fits to the data are presented. (Auth.)

  5. A Measurement of the Production of Jets in Association with a W Boson in Proton-Antiproton Collisions at the Tevatron Using Data Collected with the CDF Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Ben D. [University Coll. London

    2006-10-01

    A measurement of the diff rential pp → W + ≥ n jets production cross-section with respect to a range of different jet kinematic variables is presented. The W is required to decay leptonically to an electron and neutrino, and the kinematics of the decay products are restricted such that the electron PT > 20 GeV, electron η < 1.1, neutrino PT > 30 GeV and the W transverse mass > 20 GeV/c2. Jets are defi using the CDF JetClu cone algorithm with a radius of R = 0.4, requiring ηjet < 2.0 and ET > 15 GeV. The jet energies are corrected individually such that they are on average equal to the energy of the hadrons within the jet, with additional correction factors being applied to account for the impact of detector resolution on the jet spectra. The diff tial cross-section is measured with respect to the fi second, third and fourth jet ET spectra, the separation in R and the invariant mass of the two leading jets. In addition, the jet ET measurements can be integrated to form W + ≥ n Jets cross-section measurements for 1,2,3 and 4 jets with a range of minimum jet ET requirements, the lowest being 15 GeV. These cross-section results are compared to Enhanced Leading Order (ELO) W + jets theoretical predictions and predictions made using the leading order CKKW and MLM matching prescriptions. The ELO predictions are not suited to describ- ing the absolute rate of W + jet production, but display success in reproducing certain relative rates, dependent on the choice of renormalisation scale. The com- parisons with matching prescriptions indicate that these new approaches could be used successfully to improve W + Jets LO predictions.

  6. Antiprotons production of propagating cosmic rays under distributed reacceleration

    International Nuclear Information System (INIS)

    Simon, M.; Heinbach, U.; Koch, C.

    1987-01-01

    The available measurements on the cosmic ray anti p/p-ratio show an excess of antiprotons above predictions derived in the framework of the standard picture of cosmic ray origin and propagation. We calculated the anti p production from collisions of cosmic rays with the interstellar gas under the condition of distributed reacceleration. It could be shown that the calculated anti p/p-ratio is enhanced compared to that derived from the 'leaky box' model but it remains difficult to bring it into agreement with the data by reasonable astrophysical assumptions. (orig.)

  7. Top Production at the Tevatron: The Antiproton Awakens

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, Kenneth [Nebraska U.

    2017-07-01

    A long time ago, at a laboratory far, far away, the Fermilab Tevatron collided protons and antiprotons at $\\sqrt{s} = 1.96$ TeV. The CDF and D0 experiments each recorded datasets of about 10 fb$^{-1}$. As such experiments may never be repeated, these are unique datasets that allow for unique measurements. This presentation describes recent results from the two experiments on top-quark production rates, spin orientations, and production asymmetries, which are all probes of the $p\\bar{p}$ initial state.

  8. Measurement of the polarization for antiproton--proton annihilation into charged π and K pairs between 1.0 and 2.2 GeV/c

    International Nuclear Information System (INIS)

    Carter, A.A.; Coupland, M.; Eisenhandler, E.

    1976-01-01

    The polarization parameter for the interactions anti pp → π - π + and anti pp → K - K + was measured over essentially the full angular range at 11 momenta between 1.0 and 2.2 GeV/c. A proton target polarized perpendicular to the scattering plane was used. The experiment measured the angles and momenta of both outgoing particles using wire spark chambers and the field of the polarized target magnet. Between 1000 and 5300 π - π + events, and 140 and 1300 K - K + events, were measured at each momentum. As a check, one obtained differential cross sections for anti pp → π - π + which are in excellent agreement with previous results. The polarizations for both channels are very large and positive over much of the angular range. Preliminary results of a fit to the cross sections and asymmetries for anti pp → π - π + show strong evidence for three new resonances at 2.14, 2.36, and 2.40 GeV/c 2

  9. An Antiproton Decelerator in the CERN PS Complex

    CERN Document Server

    Riunaud, J P; Baird, S A; Boillot, J; Bosser, Jacques; Brouet, M; Caspers, Friedhelm; Chanel, M; Chohan, V; Eriksson, T; Garoby, R; Giannini, R; Giovannozzi, Massimo; Gruber, J; Hémery, J Y; Koziol, Heribert; MacCaferri, R; Maury, S; Metzmacher, K D; Möhl, D; Mulder, H; Pedersen, F; Perriollat, F; Poncet, Alain; Riunaud, J P; Serre, C; Simon, Daniel Jean; Tranquille, G; Tuyn, Jan Willem Nicolaas; Williams, B; Williams, D J

    1996-01-01

    The present CERN PS low-energy antiproton complex involves 4 machines to collect, cool, decelerate and supply experiments with up to 1010 antiprotons per pulse and per hour of momenta ranging from 0.1 to 2 GeV/c. In view of a possible future physics programme requiring low energy antiprotons, mainly to carry out studies on antihydrogen, a simplified scheme providing at low cost antiprotons at 100 MeV/c has been studied. It requires only one machine, the present Antiproton Collector (AC) converted into a cooler and decelerator (Antiproton Decelerator, AD) and delivering beam to experiments in the hall of the present Antiproton Accumulator Complex (AAC) [1]. This paper describes the feasibility study of such a scheme [2].

  10. Measurements of bottom anti-bottom azimuthal production correlations in proton - anti-proton collisions at s**(1/2) = 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Taiwan, Inst. Phys. /Argonne /INFN,

    2004-12-01

    The authors have measured the azimuthal angular correlation of b{bar b} production, using 86.5 pb{sup -1} of data collected by Collider Detector at Fermilab (CDF) in p{bar p} collisions at {radical}s = 1.8 TeV during 1994-1995. In high-energy p{bar p} collisions, such as at the Tevatron, b{bar b} production can be schematically categorized into three mechanisms. The leading-order (LO) process is ''flavor creation'', where both b and {bar b} quarks substantially participate in the hard scattering and result in a distinct back-to-back signal in final state. The ''flavor excitation'' and the ''gluon splitting'' processes, which appear at next-leading-order (NLO), are known to make a comparable contribution to total b{bar b} cross section, while providing very different opening angle distributions from the LO process. An azimuthal opening angle between bottom and anti-bottom, {Delta}{phi}, has been used for the correlation measurement to probe the interaction creating b{bar b} pairs. The {Delta}{phi} distribution has been obtained from two different methods. one method measures the {Delta}{phi} between bottom hadrons using events with two reconstructed secondary vertex tags. The other method uses b{bar b} {yields} (J/{psi}X)({ell}X') events, where the charged lepton ({ell}) is an electron (e) or a muon ({mu}), to measure {Delta}{phi} between bottom quarks. The b{bar b} purity is determined as a function of {Delta}{phi} by fitting the decay length of the J/{psi} and the impact parameter of the {ell}. Both methods quantify the contribution from higher-order production mechanisms by the fraction of the b{bar b} pairs produced in the same azimuthal hemisphere, f{sub toward}. The measured f{sub toward} values are consistent with both parton shower Monte Carlo and NLO QCD predictions.

  11. Centrifugal Separation and Equilibration Dynamics in an Electron-Antiproton Plasma

    International Nuclear Information System (INIS)

    Andresen, G. B.; Bowe, P. D.; Hangst, J. S.; Ashkezari, M. D.; Hayden, M. E.; Baquero-Ruiz, M.; Chapman, S.; Fajans, J.; Povilus, A.; So, C.; Bertsche, W.; Butler, E.; Charlton, M.; Deller, A.; Eriksson, S.; Humphries, A. J.; Madsen, N.; Werf, D. P. van der; Cesar, C. L.; Friesen, T.

    2011-01-01

    Charges in cold, multiple-species, non-neutral plasmas separate radially by mass, forming centrifugally separated states. Here, we report the first detailed measurements of such states in an electron-antiproton plasma, and the first observations of the separation dynamics in any centrifugally separated system. While the observed equilibrium states are expected and in agreement with theory, the equilibration time is approximately constant over a wide range of parameters, a surprising and as yet unexplained result. Electron-antiproton plasmas play a crucial role in antihydrogen trapping experiments.

  12. Centrifugal separation and equilibration dynamics in an electron-antiproton plasma

    CERN Document Server

    Andresen, G B; Baquero-Ruiz, Marcelo; Bertsche, William; Bowe, Paul D; Butler, Eoin; Cesar, Claudio L; Chapman, Steven; Charlton, Michael; Deller, A; Eriksson, S; Fajans, Joel; Friesen, Tim; Fujiwara, Makoto C; Gill, David R; Gutierrez, A; Hangst, Jeffrey S; Hardy, Walter N; Hayden, Michael E; Humphries, Andrew J; Hydomako, Richard; Jonsell, Svante; Madsen, Niels; Menary, Scott; Nolan, Paul; Olin, Art; Povilus, Alexander; Pusa, Petteri; Robicheaux, Francis; Sarid, Eli; Silveira, Daniel M; So, Chukman; Storey, James W; Thompson, Robert I; van der Werf, Dirk P; Wurtele, Jonathan S; Yamazaki, Yasunori

    2011-01-01

    Charges in cold, multiple-species, non-neutral plasmas separate radially by mass, forming centrifugally-separated states. Here, we report the first detailed measurements of such states in an electron-antiproton plasma, and the first observations of the separation dynamics in any centrifugally-separated system. While the observed equilibrium states are expected and in agreement with theory, the equilibration time is approximately constant over a wide range of parameters, a surprising and as yet unexplained result. Electron-antiproton plasmas play a crucial role in antihydrogen trapping experiments.

  13. Proton-Antiproton Pair Production in Two-Photon Collisions at LEP

    CERN Document Server

    Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J.A.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hakobyan, R.S.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Hu, Y.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kafer, D.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, Stefan; Rosenbleck, C.; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wienemann, P.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

    2003-01-01

    The reaction e+e- -> e+e- proton antiproton is studied with the L3 detector at LEP. The analysis is based on data collected at e+e- center-of-mass energies from 183 GeV to 209 GeV, corresponding to an integrated luminosity of 667 pb-1. The gamma gamma -> proton antiproton differential cross section is measured in the range of the two-photon center-of-mass energy from 2.1 GeV to 4.5 GeV. The results are compared to the predictions of the three-quark and quark-diquark models.

  14. A Measurement of the Top Quark Mass in 1.96 TeV Proton-Antiproton Collisions Using a Novel Matrix Element Method

    International Nuclear Information System (INIS)

    CDF Collaboration; Freeman, John; Freeman, John

    2007-01-01

    A measurement of the top quark mass in t(bar t) → l + jets candidate events, obtained from p(bar p) collisions at √s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncertainty of the jet momentum reconstruction. As with all matrix element techniques, the method involves an integration using the Standard Model matrix element for t(bar t) production and decay. However, the technique presented is unique in that the matrix element is modified to compensate for kinematic assumptions which are made to reduce computation time. Background events are dealt with through use of an event observable which distinguishes signal from background, as well as through a cut on the value of an event's maximum likelihood. Results are based on a 955 pb -1 data sample, using events with a high-p T lepton and exactly four high-energy jets, at least one of which is tagged as coming from a b quark; 149 events pass all the selection requirements. They find M meas = 169.8 ± 2.3(stat.) ± 1.4(syst.) GeV/c 2

  15. A clinical distance measure for evaluating treatment plan quality difference with Pareto fronts in radiotherapy

    Directory of Open Access Journals (Sweden)

    Kristoffer Petersson

    2017-07-01

    Full Text Available We present a clinical distance measure for Pareto front evaluation studies in radiotherapy, which we show strongly correlates (r = 0.74 and 0.90 with clinical plan quality evaluation. For five prostate cases, sub-optimal treatment plans located at a clinical distance value of >0.32 (0.28–0.35 from fronts of Pareto optimal plans, were assessed to be of lower plan quality by our (12 observers (p < .05. In conclusion, the clinical distance measure can be used to determine if the difference between a front and a given plan (or between different fronts corresponds to a clinically significant plan quality difference.

  16. Antiprotons in the CERN intersecting storage rings

    International Nuclear Information System (INIS)

    Bryant, P.J.

    1984-01-01

    High-sensitivity electronics for TTl and ring 2 had been developed and installed, the original experimental stochastic cooling systems in the ISR were rebuilt and considerably improved, the split-field magnet (SFM) vacuum chamber was modified, some steering dipoles were designed, made and installed, and finally innumerable interlocks and computer programs were revised for antiproton operation. (orig./HSI)

  17. A naturally occurring trap for antiprotons

    International Nuclear Information System (INIS)

    Eades, J.; Morita, N.; Ito, T.M.

    1993-05-01

    The phenomenon of delayed annihilation of antiprotons in helium is the first instance of a naturally occurring trap for antimatter in ordinary matter. Recent studies of this effect at CERN are summarized, and plans are described for laser excitation experiments to test its interpretation in terms of metastable exotic helium atom formation. (author)

  18. A Measurement of the Top Quark Mass in 1.96 TeV Proton-Antiproton Collisions Using a Novel Matrix Element Method

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, John [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    A measurement of the top quark mass in t$\\bar{t}$ → l + jets candidate events, obtained from p$\\bar{p}$ collisions at √s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncertainty of the jet momentum reconstruction. As with all matrix element techniques, the method involves an integration using the Standard Model matrix element for t$\\bar{t}$ production and decay. However, the technique presented is unique in that the matrix element is modified to compensate for kinematic assumptions which are made to reduce computation time. Background events are dealt with through use of an event observable which distinguishes signal from background, as well as through a cut on the value of an event's maximum likelihood. Results are based on a 955 pb-1 data sample, using events with a high-pT lepton and exactly four high-energy jets, at least one of which is tagged as coming from a b quark; 149 events pass all the selection requirements. They find Mmeas = 169.8 ± 2.3(stat.) ± 1.4(syst.) GeV/c2.

  19. Psychometric properties of the stress index radiooncology (SIRO) - a new questionnaire measuring quality of life of cancer patients during radiotherapy

    International Nuclear Information System (INIS)

    Sehlen, S.; Fahmueller, H.; Lenk, M.; Duehmke, E.; Herschbach, P.; Aydemir, U.

    2003-01-01

    Purpose: In the course of radiotherapy oncological patients often experience considerable psychosocial distress. For its measurement however, no specific questionnaire is available. The stress index radiooncology (SIRO), which is based upon the results of extensive preliminary studies, will be made available as a screening-instrument to facilitate measurement of psychosocial distress of cancer patients, including radiotherapy-induced distress. The aim of this study is, to psychometrically evaluate the preliminary version of the questionnaire, to transfer it to the final version (SIRO) and to gain information about the psychosocial distress of radiooncological patients at the beginning of radiotherapy. Patients and Methods: 104 cancer patients (18 to 85 years) with different diagnoses have been included in the study (Table 1). The data have been assessed by means of the preliminary version of the new questionnaire SIRO, the HADS, EORTC QLQ-C30 and LS. With 25 patients semistructured clinical interviews have been conducted. (orig.) [de

  20. Measurement of W + γ Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at √s = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, Naho [Okayama Univ. (Japan)

    2005-03-01

    The production cross section and the kinematic properties of the decay products of Wγ in the W → μv decay channel from p$\\bar{p}$ collisions at √s = 1.96 TeV are presented. The measurement use the high pT muon data from the upgraded Collider Detector at Fermilab (CDF). The data were collected between March 2002 and September 2003. The total integrated luminosities are 192 pb-1 with the muon detector which covers the pseudorapidity region of |η| ≤ 0.6 and 175 pb-1 with the muon detector covering the region 0.6 ≤ |η| ≤ 1.0. In the Standard Model the μvγ final states occur due to Wγ → μvγ production and via muon Bremsstrahlung, W → μv → μvγ. W bosons are selected in their muon decay mode. Additionally, photons with transverse energy above 7 GeV, pseudorapidity in the central region (|η| < 1.1) and muon-photon angular separation ΔR(μ,γ) > 0.7 are selected. The author observes a total of 128 Wγ candidates, whereas the Standard Model expectation is 142.4 ± 9.5 events. The Wγ production cross section is found to be σ(p$\\bar{p}$ → μvγ) = 16.3 ± 2.3(stat.) ± 1.8(syst.) ± 1.2(lum.) [pb]. The theoretical prediction for this cross section is σ(p$\\bar{p}$ → lvγ) = 19.3 ± 1.4(th.) [pb]. The Standard Model predictions for several kinematic + variables are compared with data for ETγ > 7 GeV and ΔR(μ,γ) > 0.7. The measured cross section and the photon and W boson production kinematics are found to agree with the Standard Model predictions.

  1. Measurements of the B Production Cross Section in Proton-Antiproton Collisions at √s = 1.96 TeV using semileptonic decays of b hadrons

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, James Alexander [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2006-07-01

    The authors present a measurement of the cross section of b hadron (Hb) production in p$\\bar{p}$ collisions at √s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron. They use 83 pb-1 of data taken between october 2002 and May 2003 that was collected with a trigger sensitive to high momentum muons and displaced tracks. They use partially reconstructed decays in the following modes: Hb → μ- $\\bar{v}$μD0X, D0 → K-π+, and Hb → μ-$\\bar{v}$μD*+ X, D*+ → D0π+, D0 → K- π+, and their charge conjugates. They correct for the backgrounds from c$\\bar{c}$ and b$\\bar{b}$ decays, for trigger and reconstruction efficiencies, and for detector acceptance. They report the total cross section above a minimum transverse momentum (pT) of 9 GeV/c for the rapidity range |y| ≤ 0.6.

  2. Evaluation of the shield calculation adequacy of radiotherapy rooms through Monte Carlo Method and experimental measures

    International Nuclear Information System (INIS)

    Meireles, Ramiro Conceicao

    2016-01-01

    The shielding calculation methodology for radiotherapy services adopted in Brazil and in several countries is that described in publication 151 of the National Council on Radiation Protection and Measurements (NCRP 151). This methodology however, markedly employs several approaches that can impact both in the construction cost and in the radiological safety of the facility. Although this methodology is currently well established by the high level of use, some parameters employed in the calculation methodology did not undergo to a detailed assessment to evaluate the impact of the various approaches considered. In this work the MCNP5 Monte Carlo code was used with the purpose of evaluating the above mentioned approaches. TVLs values were obtained for photons in conventional concrete (2.35g / cm 3 ), considering the energies of 6, 10 and 25 MeV, respectively, first considering an isotropic radiation source impinging perpendicular to the barriers, and subsequently a lead head shielding emitting a shaped beam, in the format of a pyramid trunk. Primary barriers safety margins, taking in account the head shielding emitting photon beam pyramid-shaped in the energies of 6, 10, 15 and 18 MeV were assessed. A study was conducted considering the attenuation provided by the patient's body in the energies of 6,10, 15 and 18 MeV, leading to new attenuation factors. Experimental measurements were performed in a real radiotherapy room, in order to map the leakage radiation emitted by the accelerator head shielding and the results obtained were employed in the Monte Carlo simulation, as well as to validate the entire study. The study results indicate that the TVLs values provided by (NCRP, 2005) show discrepancies in comparison with the values obtained by simulation and that there may be some barriers that are calculated with insufficient thickness. Furthermore, the simulation results show that the additional safety margins considered when calculating the width of the primary

  3. Conceptual Design of an Antiproton Generation and Storage Facility

    Energy Technology Data Exchange (ETDEWEB)

    Peggs, Stephen

    2006-10-24

    The Antiproton Generation and Storage Facility (AGSF) creates copious quantities of antiprotons, for bottling and transportation to remote cancer therapy centers. The first step in the generation and storage process is to accelerate an intense proton beam down the Main Linac for injection into the Main Ring, which is a Rapid Cycling Synchrotron that accelerates the protons to high energy. The beam is then extracted from the ring into a transfer line and into a Proton Target. Immediately downstream of the target is an Antiproton Collector that captures some of the antiprotons and focuses them into a beam that is transported sequentially into two antiproton rings. The Precooler ring rapidly manipulates antiproton bunches from short and broad (in momentum) to long and thin. It then performs some preliminary beam cooling, in the fraction of a second before the next proton bunch is extracted from the Main Ring. Pre-cooled antiprotons are passed on to the Accumulator ring before the next antiprotons arrive from the target. The Accumulator ring cools the antiprotons, compressing them into a dense state that is convenient for mass storage over many hours. Occasionally the Accumulator ring decelerates a large number of antiprotons, injecting them into a Deceleration Linac that passes them into a waiting Penning trap.

  4. Conceptual Design of an Antiproton Generation and Storage Facility

    International Nuclear Information System (INIS)

    Peggs, Stephen

    2006-01-01

    The Antiproton Generation and Storage Facility (AGSF) creates copious quantities of antiprotons, for bottling and transportation to remote cancer therapy centers. The first step in the generation and storage process is to accelerate an intense proton beam down the Main Linac for injection into the Main Ring, which is a Rapid Cycling Synchrotron that accelerates the protons to high energy. The beam is then extracted from the ring into a transfer line and into a Proton Target. Immediately downstream of the target is an Antiproton Collector that captures some of the antiprotons and focuses them into a beam that is transported sequentially into two antiproton rings. The Precooler ring rapidly manipulates antiproton bunches from short and broad (in momentum) to long and thin. It then performs some preliminary beam cooling, in the fraction of a second before the next proton bunch is extracted from the Main Ring. Pre-cooled antiprotons are passed on to the Accumulator ring before the next antiprotons arrive from the target. The Accumulator ring cools the antiprotons, compressing them into a dense state that is convenient for mass storage over many hours. Occasionally the Accumulator ring decelerates a large number of antiprotons, injecting them into a Deceleration Linac that passes them into a waiting Penning trap

  5. Status Report for Experiment AD-4/ACE Biological Effectiveness of Antiproton Annihilation

    CERN Document Server

    Holzscheiter, M H; Angelopoulos, Angelo; Bassler, Niels; Beyer, Gerd; Currell, Fred; De Marco, John; Doser, Michael; Hajdukovic, Dragan; Hartley, Oliver; Kavanagh, Joy; Iwamoto, Kei; Jäkel, Oliver; Kantemiris, Ioannis; Knudsen, Helge; Kovacevic, Sandra; McBride, Bill; Møller, Søren Pape; Overgaard, Jens; Petersen, Jørgen; Ratib, Osman; Schettino, Giuseppe; Timson, David; Singers-Sørensen, Brita; Solberg, Timothy; Vranjes, Sanja; Wouters, Brad

    2009-01-01

    Status report for experiment AD-4/ACE showing recent progress in RBE measurements for V79 Chinese Hamster cells irradiated with antiprotons. Also discussed are initial test experiments using the H2AX assay to study DNA damage to cells and initial experiments using liquid ionization chambers.

  6. Antiproton-nucleus interactions at 5 to 9 GeV/c

    International Nuclear Information System (INIS)

    Ahmad, S.; Bonner, B.E.; Buchanan, J.A.; Chan, C.S.; Clement, J.M.; Eiseman, S.E.; Empl, A.; Etkin, A.; Foley, K.J.; Hackenburg, R.W.; Hallman, T.J.; Kramer, M.A.; Kruk, J.; Lindenbaum, S.J.; Longacre, R.S.; Love, W.A.; Madansky, L.; Morris, W.; Mutchler, G.S.; Peaslee, D.C.; Platner, E.D.; Saulys, A.C.; Toshkov, S.

    1993-01-01

    Antiproton beams of 5, 7 and 9 GeV/c were used to interact with C, Al, Cu, Sn and Pb nuclear targets. Charged particle multiplicity distributions, strange particle production cross sections and rapidity distributions were measured. The charged particle multiplicities are reported in this paper. (orig.)

  7. Measurement of Thyroid Dose by TLD arising from Radiotherapy of Breast Cancer Patients from Supraclavicular Field

    Directory of Open Access Journals (Sweden)

    Farhood B.

    2016-06-01

    Full Text Available Background: Breast cancer is the most frequently diagnosed cancer and the leading global cause of cancer death among women worldwide. Radiotherapy plays a significant role in treatment of breast cancer and reduces locoregional recurrence and eventually improves survival. The treatment fields applied for breast cancer treatment include: tangential, axillary, supraclavicular and internal mammary fields. Objective: In the present study, due to the presence of sensitive organ such as thyroid inside the supraclavicular field, thyroid dose and its effective factors were investigated. Materials and Methods: Thyroid dose of 31 female patients of breast cancer with involved supraclavicular lymph nodes which had undergone radiotherapy were measured. For each patient, three TLD-100 chips were placed on their thyroid gland surface, and thyroid doses of patients were measured. The variables of the study include shield shape, the time of patient’s setup, the technologists’ experience and qualification. Finally, the results were analyzed by ANOVA test using SPSS 11.5 software. Results: The average age of the patients was 46±10 years. The average of thyroid dose of the patients was 140±45 mGy (ranged 288.2 and 80.8 in single fraction. There was a significant relationship between the thyroid dose and shield shape. There was also a significant relationship between the thyroid dose and the patient’s setup time. Conclusion: Beside organ at risk such as thyroid which is in the supraclavicular field, thyroid dose possibility should be reduced. For solving this problem, an appropriate shield shape, the appropriate time of the patient’s setup, etc. could be considered.

  8. High precision spectroscopy of pionic and antiprotonic atoms

    International Nuclear Information System (INIS)

    El-Khoury, P.

    1998-04-01

    The study of exotic atoms, in which an orbiting electron of a normal atom is replaced by a negatively charged particle (π - , μ - , p, Κ - , Σ - ,...) may provide information on the orbiting particle and the atomic nucleus, as well as on their interaction. In this work, we were interested in pionic atoms (π -14 N) on the one hand in order to determine the pion mass with high accuracy (4 ppm), and on the other hand in antiprotonic atoms (pp-bar) in order to study the strong nucleon-antinucleon interaction at threshold. In this respect, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high stop density for particles in gas targets at low pressure. Using curved crystals, an extended X-ray source could be imaged onto the detector. Charge-Coupled Devices were used as position sensitive detectors in order to measure the Bragg angle of the transition to a high precision. The use of gas targets resolved the ambiguity owing to the number of K electrons for the value of the pion mass, and, for the first time, strong interaction shift and broadening of the 2p level in antiprotonic hydrogen were measured directly. (author)

  9. Surface dose measurement with Gafchromic EBT3 film for intensity modulated radiotherapy technique

    Science.gov (United States)

    Akbas, Ugur; Kesen, Nazmiye Donmez; Koksal, Canan; Okutan, Murat; Demir, Bayram; Becerir, Hatice Bilge

    2017-09-01

    Accurate dose measurement in the buildup region is extremely difficult. Studies have reported that treatment planning systems (TPS) cannot calculate surface dose accurately. The aim of the study was to compare the film measurements and TPS calculations for surface dose in head and neck cancer treatment using intensity modulated radiation therapy (IMRT). IMRT plans were generated for 5 head and neck cancer patients by using Varian Eclipse TPS. Quality assurance (QA) plans of these IMRT plans were created on rando phantoms for surface dose measurements. EBT3 films were cut in size of 2.5 x 2.5 cm2 and placed on the left side, right side and the center of larynx and then the films were irradiated with 6 MV photon beams. The measured doses were compared with TPS. The results of TPS calculations were found to be lower compared to the EBT3 film measurements at all selected points. The lack of surface dose calculation in TPS should be considered while evaluating the radiotherapy plans.

  10. Active on-line detector for in-room radiotherapy neutron measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, F., E-mail: faustino.gomez@usc.e [Dpt. Fisica de Particulas, Facultad de Fisica, Campus Sur, Univ. Santiago de Compostela, Santiago 15782 (Spain); Sanchez-Doblado, F. [Dpt. de Fisiologia Medica y Biofisica, Univ. Sevilla, Sevilla (Spain); Hospital Virgen Macarena, Sevilla (Spain); Iglesias, A. [Dpt. Fisica de Particulas, Facultad de Fisica, Campus Sur, Univ. Santiago de Compostela, Santiago 15782 (Spain); Domingo, C. [Dpt. Fisica, Univ. Autonoma Barcelona, Barcelona (Spain)

    2010-12-15

    The measurement of the neutron fluence produced inside a radiotherapy installation has been a matter of concern specially in the photon high megavoltage modalities. Until now, due to the pulsed nature of the beam and the high photon fluence inside the radiotherapy room, only passive methods were considered reliable. In this work we describe a neutron detector, based on neutron sensitive SRAM devices, that can operate inside the treatment room and is insensitive to the scattered photon fluence. This device has been used to estimate the neutron production and the patient exposure to neutrons in several clinical installations with different linac commercial models. The detection principle is based on the production of Single Event Upset (SEU) of memory states on modern sub-micron technology SRAMs. Spectral sensitivity was initially studied using low energy neutron shielding (boron and cadmium layers) and later using dedicated calibration neutron beams. With a 3 mm thick flex-boron shield, the SEU rate was reduced to around 5% of the unshielded rate, demonstrating that the dominant contribution of the SEU cross section of the chosen SRAM was due to low energy neutrons. The total memory size was scaled to obtain a response repeatability with relative typical uncertainty of about 2% for 1000 Monitor Units (MU) in a 15 MV accelerator facility with excellent linearity with MU. The sensitivity of this digital detector is around 0.3 {mu}Sv H{sup *}(10) per event and considering the signal to fluence ratio around 2 x 10{sup -4} event cm{sup 2}.

  11. Two-photon laser spectroscopy of antiprotonic helium and the antiproton-to-electron mass ratio

    CERN Document Server

    Hori, Masaki; Barna, Daniel; Andreas Dax,; Hayano, Ryugo; Friedreich, Susanne; Juhász, Bertalan; Pask, Thomas; Widmann, Eberhard; Horváth, Dezső; Venturelli, Luca; Zurlo, Nicola; 10.1038/nature10260

    2013-01-01

    Physical laws are believed to be invariant under the combined transformations of charge, parity and time reversal (CPT symmetry). This implies that an antimatter particle has exactly the same mass and absolute value of charge as its particle counterpart. Metastable antiprotonic helium ($\\bar{p}He^+$) is a three-body atom2 consisting of a normal helium nucleus, an electron in its ground state and an antiproton ($\\bar{p}$) occupying a Rydberg state with high principal and angular momentum quantum numbers, respectively n and l, such that n ≈ l + 1 ≈ 38. These atoms are amenable to precision laser spectroscopy, the results of which can in principle be used to determine the antiproton-to-electron mass ratio and to constrain the equality between the antiproton and proton charges and masses. Here we report two-photon spectroscopy of antiprotonic helium, in which $\\bar{p}^{3}He^{+}$ and $\\bar{p}^{4}He^{+}$ isotopes are irradiated by two counter-propagating laser beams. This excites nonlinear, two-phot...

  12. CERN accelerator school: Antiprotons for colliding beam facilities

    International Nuclear Information System (INIS)

    Bryant, P.; Newman, S.

    1984-01-01

    This is a specialized course which addresses a wide spectrum of theoretical and technological problems confronting the designer of an antiproton facility for high-energy-physics research. A broad and profound basis is provided by the lecturers' substantial experience gained over many years with CERN's unique equipment. Topics include beam optics, special lattices for antiproton accumulation and storage rings, antiproton production, stochastic cooling, acceleration and storage, r.f. noise, r.f. beam manipulations, beam-beam interaction, beam stability due to ion accumulation, and diagnostics. The SPS (Super Proton Synchrotron) panti p collider, LEAR (the Low Energy Antiproton Ring at CERN), antiprotons in the ISR (Intersecting Storage Rings), the new antiproton collector (ACOL) and gas jet targets are also discussed. A table is included listing the parameters of all CERN's accelerators and storage rings. See hints under the relevant topics. (orig./HSI)

  13. Antiproton rate estimates for the 1996 E866 experiment

    International Nuclear Information System (INIS)

    Shea, J.Y.; Garcia-Solis, E.J.; Stanskas, P.J.

    1996-01-01

    There has always been a strong interest to study antiprotons produced in relativistic heavy ion collisions. A specific point has been a puzzle for years in that both ARC and RQMD predict the correct antiproton yield for Au+Au collisions at the AGS, but with two entirely different physical explanations. The RQMD is able to describe available data by relying on the enhanced production of antiprotons, followed by the annihilation of a large fraction of the produced antiprotons. Conversely, ARC describes the data by producing less antiprotons initially, but the annihilation of the antiprotons is open-quotes screenedclose quotes in the high density environment of the collision on account of collisions with mesons. It is then particularly interesting to studying the shadowing effect in the Au-Au collisions at the AGS to shine a light in the theoretical debate in heavy-ion collisions

  14. Collisions of antiprotons with hydrogen molecular ions

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2009-01-01

    Time-dependent close-coupling calculations of the ionization and excitation cross section for antiproton collisions with molecular hydrogen ions are performed in an impact energy range from 0.5 keV to 10 MeV. The Born-Oppenheimer and Franck-Condon approximations as well as the impact parameter...... method are applied in order to describe the target molecule and the collision process. It is shown that three perpendicular orientations of the molecular axis with respect to the trajectory are sufficient to accurately reproduce the ionization cross section calculated by Sakimoto [Phys. Rev. A 71, 062704...... (2005)] reducing the numerical effort drastically. The independent-event model is employed to approximate the cross section for double ionization and H+ production in antiproton collisions with H2....

  15. Challenging the Standard Model: High-Precision Comparisons of the Fundamental Properties of Protons and Antiprotons

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    The Baryon Antibaryon Symmetry Experiment (BASE-CERN) at CERN’s antiproton decelerator facility is aiming at high-precision comparisons of the fundamental properties of protons and antiprotons, such as charge-to-mass ratios, magnetic moments and lifetimes. Such experiments provide sensitive tests of the fundamental charge-parity-time invariance in the baryon sector. BASE was approved in 2013 and has measured since then, utilizing single-particle multi-Penning-trap techniques, the antiproton-to-proton charge-to-mass ratio with a fractional precision of 69 p.p.t. [1], as well as the antiproton magnetic moment with fractional precisions of 0.8 p.p.m. and 1.5 p.p.b., respectively [2]. At our matter companion experiment BASE-Mainz, we have performed proton magnetic moment measurements with fractional uncertainties of 3.3 p.p.b. [3] and 0.3 p.p.b. [4]. By combining the data of both experiments we provide a baryon-magnetic-moment based CPT test gpbar/gp = 1.000 000 000 2(15), which improves the uncertainty of p...

  16. Reliability of the Fermilab Antiproton Source

    International Nuclear Information System (INIS)

    Harms, E. Jr.

    1993-05-01

    This paper reports on the reliability of the Fermilab Antiproton source since it began operation in 1985. Reliability of the complex as a whole as well as subsystem performance is summarized. Also discussed is the trending done to determine causes of significant machine downtime and actions taken to reduce the incidence of failure. Finally, results of a study to detect previously unidentified reliability limitations are presented

  17. Potential kaon and antiproton beams at BNL

    International Nuclear Information System (INIS)

    Lazarus, D.M.

    1991-01-01

    The AGS at Brookhaven is the worlds most prolific producer of kaons and low energy antiprotons during operations. With the imminent operation of the AGS Booster which will increase intensities by an anticipated factor of six in the next few years, it will become possible to have purified beams of particles containing strange quarks and anti-quarks with intensities comparable to the pion beams which have so successfully dominated precision hadron spectroscopy in the past. 10 refs., 3 figs

  18. Magnetic horn of the Antiproton Accumulator (AA)

    CERN Multimedia

    Photographic Service

    1988-01-01

    In the 1960s, the invention of this "current sheet lens" has helped to greatly improve the flux of neutrino beams. It was used again at the AA, collecting antiprotons from the production target at angles too large to fit into the acceptance of the AA. It was machined from aluminium to a thickness of 1.4 mm and pulsed at 400 kA for 15 microseconds (half-sine).

  19. An analytical simulation of the ion-antiproton instabilities in the CERN Antiproton Accumulator

    International Nuclear Information System (INIS)

    Dainelli, A.; Pusterla, M.

    1988-01-01

    A direct map method with a Mathieu approach to tune modulation is proposed and used to simulate nonlinear effects on particle motion that are generated by a beam-beam-like interaction of antiprotons with ions of the residual gas in the CERN Antiproton Accumulator. Two different Gaussian ion distributions are used, and the effects of the simulated beam-beam force on the particle motion is studied in phase space, with a particular attention to high-order nonlinear resonances. (author) 16 refs., 4 figs

  20. Closing in on mass-degenerate dark matter scenarios with antiprotons and direct detection

    International Nuclear Information System (INIS)

    Garny, Mathias; Ibarra, Alejandro; Pato, Miguel; Vogl, Stefan

    2012-01-01

    Over the last years both cosmic-ray antiproton measurements and direct dark matter searches have proved particularly effective in constraining the nature of dark matter candidates. The present work focusses on these two types of constraints in a minimal framework which features a Majorana fermion as the dark matter particle and a scalar that mediates the coupling to quarks. Considering a wide range of coupling schemes, we derive antiproton and direct detection constraints using the latest data and paying close attention to astrophysical and nuclear uncertainties. Both signals are strongly enhanced in the presence of degenerate dark matter and scalar masses, but we show that the effect is especially dramatic in direct detection. Accordingly, the latest direct detection limits take the lead over antiprotons. We find that antiproton and direct detection data set stringent lower limits on the mass splitting, reaching 19% at a 300 GeV dark matter mass for a unity coupling. Interestingly, these limits are orthogonal to ongoing collider searches at the Large Hadron Collider, making it feasible to close in on degenerate dark matter scenarios within the next years

  1. Closing in on mass-degenerate dark matter scenarios with antiprotons and direct detection

    Energy Technology Data Exchange (ETDEWEB)

    Garny, Mathias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ibarra, Alejandro; Pato, Miguel; Vogl, Stefan [Technische Univ. Muenchen, Garching (Germany). Physik-Department

    2012-07-15

    Over the last years both cosmic-ray antiproton measurements and direct dark matter searches have proved particularly effective in constraining the nature of dark matter candidates. The present work focusses on these two types of constraints in a minimal framework which features a Majorana fermion as the dark matter particle and a scalar that mediates the coupling to quarks. Considering a wide range of coupling schemes, we derive antiproton and direct detection constraints using the latest data and paying close attention to astrophysical and nuclear uncertainties. Both signals are strongly enhanced in the presence of degenerate dark matter and scalar masses, but we show that the effect is especially dramatic in direct detection. Accordingly, the latest direct detection limits take the lead over antiprotons. We find that antiproton and direct detection data set stringent lower limits on the mass splitting, reaching 19% at a 300 GeV dark matter mass for a unity coupling. Interestingly, these limits are orthogonal to ongoing collider searches at the Large Hadron Collider, making it feasible to close in on degenerate dark matter scenarios within the next years.

  2. Development of a deep inspiration breath-hold system for radiotherapy utilizing a laser distance measurer.

    Science.gov (United States)

    Jensen, Christer Andre; Skottner, Nils; Frengen, Jomar; Lund, Jo-Åsmund

    2017-01-01

    Deep inspiration breath-hold (DIBH) is a technique for treating left-sided breast cancer (LSBC). In modern radiotherapy, one of the main aims is to exclude the heart from the beam aperture with an individualized beam design for LSBC. A deep inhalation will raise the chest wall while the volume of the lungs increase, this will again push the heart away from the breast to be treated. There are a few commercial DIBH systems, both invasive and noninvasive. We present an alternative noninvasive DIBH system based upon an industrial laser distance measurer. This system can be installed in a treatment room at a low cost; it is very easy to use and requires limited amount of training for the personnel and the patient. The system is capable of measuring the position of the chest wall with high frequency and precision in real time. The patient views its breathing curve through video glasses, and gets instructions during the treatment session. The system is well tolerated by test subjects due to its noninvasiveness. © 2016 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  3. Conformal fields in prostate radiotherapy: A comparison between measurement, calculation and simulation

    Directory of Open Access Journals (Sweden)

    Seied R Mahdavi

    2012-01-01

    Full Text Available Aims: The objective of this study is to evaluate the accuracy of a treatment planning system (TPS for calculating the dose distribution parameters in conformal fields (CF. Dosimetric parameters of CF′s were compared between measurement, Monte Carlo simulation (MCNP4C and TPS calculation. Materials and Methods: Field analyzer water phantom was used for obtaining percentage depth dose (PDD curves and beam profiles (BP of different conformal fields. MCNP4C was used to model conformal fields dose specification factors and head of linear accelerator varian model 2100C/D. Results: Results showed that the distance to agreement (DTA and dose difference (DD of our findings were well within the acceptance criteria of 3 mm and 3%, respectively. Conclusions: According to this study it can be revealed that TPS using equivalent tissue air ratio calculation method is still convenient for dose prediction in non small conformal fields normally used in prostate radiotherapy. It was also showed that, since there is a close correlation with Monte Carlo simulation, measurements and TPS, Monte Carlo can be further confirmed for implementation and calculation dose distribution in non standard and complex conformal irradiation field for treatment planning systems.

  4. A new active method for the measurement of slow-neutron fluence in modern radiotherapy treatment rooms

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, F; Iglesias, A [Departamento de Fisica de Particulas, Universidad de Santiago, 15782-Santiago (Spain); Doblado, F Sanchez [Hospital Universitario Virgen Macarena, Radiofisica and Departamento de Fisiologia Medica y Biofisica, Facultad de Medicina, Universidad de Sevilla (Spain)], E-mail: faustino.gomez@usc.es

    2010-02-21

    This work focuses on neutron monitoring at clinical linac facilities during high-energy modality radiotherapy treatments. Active in-room measurement of neutron fluence is a complex problem due to the pulsed nature of the fluence and the presence of high photon background, and only passive methods have been considered reliable until now. In this paper we present a new active method to perform real-time measurement of neutron production around a medical linac. The device readout is being investigated as an estimate of patient neutron dose exposure on each radiotherapy session. The new instrument was developed based on neutron interaction effects in microelectronic memory devices, in particular using neutron-sensitive SRAM devices. This paper is devoted to the description of the instrument and measurement techniques, presenting the results obtained together with their comparison and discussion. Measurements were performed in several standard clinical linac facilities, showing high reliability, being insensitive to the photon fluence and EM pulse present inside the radiotherapy room, and having detector readout statistical relative uncertainties of about 2% on measurement of neutron fluence produced by 1000 monitor units irradiation runs.

  5. Study of the low energy proton-antiproton annihilation interaction leading to: π+ π-, K+K- and e+e-. Study of the proton form factors in the time region

    International Nuclear Information System (INIS)

    Zekri, N.

    1988-01-01

    The results of the PS170 experiments are reported. The proton form factors from proton-antiproton → positron-electron reaction and the cross sections of the proton-antiproton → pion plus - pion minus annihilation reaction are investigated. The performances of the measuring instruments concerning electron selectivity, geometrical acceptance, efficiency, reliability in the measurement of momenta and particle discrimination accuracy. Particular attention was given to the Cherenkov detector parameters. The experimental results are analyzed and radiative corrections are carried out for the proton-antiproton → positron-electron reactions. The reaction angular distribution is measured. The obtained results are in good agreement with VDM calculations. The proton-antiproton → pion plus - pion minus cross section between, 160 and 260 MeV/c is calculated and compared to the antiproton annihilation cross section calculated on the basis of the quark annihilation exchange process [fr

  6. Design and development of a silicon-segmented detector for 2D dose measurements in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Menichelli, David [Department of Clinical Phisiopathology, University of Florence, v.le Morgagni, 85-50134 Florence (Italy); INFN, Florence division, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy)], E-mail: david.menichelli@cern.ch; Bruzzi, Mara [Department of Energetics, University of Florence, via S. Marta, 3-50139 Florence (Italy); INFN, Florence division, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Bucciolini, Marta; Talamonti, Cinzia; Casati, Marta; Marrazzo, Livia [Department of Clinical Phisiopathology, University of Florence, v.le Morgagni, 85-50134 Florence (Italy); INFN, Florence division, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Tesi, Mauro [Department of Energetics, University of Florence, via S. Marta, 3-50139 Florence (Italy); Piemonte, Claudio; Pozza, Alberto; Zorzi, Nicola [ITC-irst, via Sommarive, 18-38050 Trento (Italy); Brianzi, Mirko [INFN, Florence division, Via G. Sansone 1, 50019 Sesto Fiorentino (Italy); De Sio, Antonio [Department of Astronomy and Space Science, University of Florence, L.go E. Fermi, 2-50125 Florence (Italy)

    2007-12-11

    Modern radiotherapy treatment techniques, such as intensity Modulated Radiation Therapy (IMRT) and protontherapy, require detectors with specific features, usually not available in conventional dosimeters. IMRT dose measurements, for instance, must face non-uniform beam fluences as well as a time-varying dose rate. Two-dimensional detectors present a great interest for dosimetry in beams with steep dose gradients, but they must satisfy a number of requirements and, in particular, they must exhibit high spatial resolution. With the aim of developing a dosimetric system adequate for 2D pre-treatment dose verifications, we designed a modular dosimetric device based on a monolithic silicon-segmented module. State and results of this work in progress are described in this article. The first 441 pixels, 6.29x6.29 cm{sup 2} silicon module has been produced by ion implantation on a 50 {mu}m thick p-type epitaxial layer. This sensor has been connected to a discrete readout electronics performing current integration, and has been tested with satisfactory results. In the final configuration, nine silicon modules will be assembled together to cover an area close to 20x20 cm{sup 2} with 3969 channels. In this case, the readout electronics will be based on an ASIC capable to read 64 channels by performing current-to-frequency conversion.

  7. Study of the anti-hydrogen atom and ion formation in the collisions antiproton-positronium

    International Nuclear Information System (INIS)

    Comini, Pauline

    2014-01-01

    The future CERN experiment called GBAR intends to measure the gravitational acceleration of antimatter on Earth using cold (neV) anti-hydrogen atoms undergoing a free fall. The experiment scheme first needs to cool anti-hydrogen positive ions, obtained thanks to two consecutive reactions occurring when an antiproton beam collides with a dense positronium cloud.The present thesis studies these two reactions in order to optimise the production of the anti-ions. The total cross sections of both reactions have been computed in the framework of a perturbation theory model (Continuum Distorted Wave - Final State), in the range 0 to 30 keV antiproton kinetic energy; several excited states of positronium have been investigated. These cross sections have then been integrated to a simulation of the interaction zone where antiprotons collide with positronium; the aim is to find the optimal experimental parameters for GBAR. The results suggest that the 2P, 3D or, to a lower extend, 1S states of positronium should be used, respectively with 2, less than 1 or 6 keV antiprotons. The importance of using short pulses of antiprotons has been underlined; the positronium will have to be confined in a tube of 20 mm length and 1 mm diameter. In the prospect of exciting the 1S-3D two-photon transition in positronium at 410 nm, a pulsed laser system had already been designed. It consists in the frequency doubling of an 820 nm pulsed titanium-sapphire laser. The last part of the thesis has been dedicated to the realisation of this laser system, which delivers short pulses (9 ns) of 4 mJ energy at 820 nm. (author) [fr

  8. Serach for polarization effects in the antiproton production process

    CERN Multimedia

    It is proposed to study polarization effects in the production of antiprotons at the PS test beam line T11 at 3.5 GeV/c momentum. A polarization in the production process has never been studied but if existing it would allow for a rather simple and cheap way to generate a polarized antiproton beam with the existing facilities at CERN.

  9. Antiproton-nucleus experiments at LEAR and KAON

    International Nuclear Information System (INIS)

    Yavin, A.I.

    1989-12-01

    Antimatter and matter-antimatter systems are briefly discussed. Results of the antiproton-nucleus scattering experiments at LEAR are described, with the emphasis on unfinished experiments and on proposed experiments yet untouched. A few remarks on antiproton and antideuteron experiments at KAON are then presented

  10. Low-energy antiprotons physics and the FLAIR facility

    International Nuclear Information System (INIS)

    Widmann, E

    2015-01-01

    FLAIR, the Facility for low-energy antiproton and ion research has been proposed in 2004 as an extension of the planned FAIR facility at Darmstadt, Germany. FLAIR was not included into the modularized start version of FAIR, but the recent installation of the CRYRING storage ring at GSI Darmstadt has opened new perspectives for physics with low-energy antiprotons at FAIR. (paper)

  11. Antiproton impact ionization of atomic hydrogen and helium

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 INN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2009-11-01

    We shall present results for antiproton ionization of H and He ranging from fully differential cross sections to total ionization. The calculations have been made in a coupled pseudostate impact parameter approximation. It will be shown that the interaction between the antiproton and the target nucleus is very important at low energies.

  12. Detailed analysis of observed antiprotons in cosmic rays

    Directory of Open Access Journals (Sweden)

    P Davoudifar

    2009-12-01

    Full Text Available In the present work, the origin of antiprotons observed in cosmic rays (above the atmosphere is analyzed in details. We have considered the origin of the primaries, (which their interactions with the interstellar medium is one of the most important sources of antiprotons is a supernova type II then used a diffusion model for their propagation. We have used the latest parameterization for antiproton production cross section in pp collisions (instead of well known parameterization introduced by Tan et al. as well as our calculated residence time for primaries. The resulted intensity shows the secondary antiprotons produced in pp collisions in the galaxy, have a high population as one can not consider an excess for extragalactic antiprotons. Also there is a high degree of uncertainty in different parameters.

  13. Carbon filament beam profile monitor for high energy proton-antiproton storage rings

    International Nuclear Information System (INIS)

    Evans, L.R.; Shafer, R.E.

    1979-01-01

    The measurement of the evolution of the transverse profile of the stored beams in high energy proton storage rings such as the p-anti p colliders at CERN and at FNAL is of considerable importance. In the present note, a simple monitor is discussed which will allow almost non-destructive measurement of the profile of each individual proton and antiproton bunch separately. It is based on the flying wire technique first used at CEA and more recently at the CPS. A fine carbon filament is passed quickly through the beam, acting as a target for secondary particle production. The flux of secondary particles is measured by two scintillator telescopes, one for protons and one for antiprotons, having an angular acceptance between 30 and 100 mrad. Measurements of secondary particle production performed at FNAL in this angular range show that a very respectable flux can be expected

  14. Fermilab Antiproton source, Recycler ring and Main Injector

    Energy Technology Data Exchange (ETDEWEB)

    Nagaitsev, Sergei [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-03-22

    The antiproton source for a proton-antiproton collider at Fermilab was proposed in 1976 [1]. The proposal argued that the requisite luminosity (~1029 cm-2sec-1) could be achieved with a facility that would produce and cool approximately 1011 antiprotons per day. Funding for the Tevatron I project (to construct the Antiproton source) was initiated in 1981 and the Tevatron ring itself was completed, as a fixed target accelerator, in the summer of 1983 and the Antiproton Source was completed in 1985. At the end of its operations in 2011, the Fermilab antiproton production complex consisted of a sophisticated target system, three 8-GeV storage rings (namely the Debuncher, Accumulator and Recycler), 25 independent multi-GHz stochastic cooling systems, the world’s only relativistic electron cooling system and a team of technical experts equal to none. Sustained accumulation of antiprotons was possible at the rate of greater than 2.5×1011 per hour. Record-size stacks of antiprotons in excess of 3×1012 were accumulated in the Accumulator ring and 6×1012 in the Recycler. In some special cases, the antiprotons were stored in rings for more than 50 days. Note, that over the years, some 1016 antiprotons were produced and accumulated at Fermilab, which is about 17 nanograms and more than 90% of the world’s total man-made quantity of nuclear antimatter. The accelerator complex at Fermilab supported a broad physics program including the Tevatron Collider Run II [2], neutrino experiments using 8 GeV and 120 GeV proton beams, as well as a test beam facility and other fixed target experiments using 120 GeV primary proton beams. The following sections provide a brief description of Fermilab accelerators as they operated at the end of the Collider Run II (2011).

  15. The potential of californium-252 in radiotherapy. Preclinical measurements in physics and radiobiology.

    Science.gov (United States)

    Hall, E J; Rossi, H

    1975-10-01

    Californium-252 is a man-made radionuclide (half-life 2-65 years) which emits a mixture of neutrons and gamma rays. It is used in radiotherapy as an alternative to radium and extends the potential benefits of neutrons to interstitial and intracavitary applications. Gamma rays account for a variable proportion of the dose (30 to 50 per cent), depending on the source filtration and the distance from the source. Dosimetry is complicated by this mixture of neutrons and gamma rays. However, measurements with paired ion-chambers, together with Monte-Carlo calculations, have produced dosimetric data that are adequate for clinical use. Many determinations of the oxygen enhancement ratio (OER) have been reported. At the low dose-rates characteristic of interstitial implants, the OER is about 1-5. This is essentially the figure for fast neutrons alone, since at very low dose-rates the contribution of the gamma rays to the biological effect is negligible. As the dose increases, there is a corresponding rise in the OER because the gamma ray contribution can no longer be ignored. The OER is likely to be about 1-8 if 252Cf is used in intracavity treatments and 2-0 if used in "acute" exposures in devices such as the Cathetron. The relative biological effectivenesss (RBE) varies with dose-rate, and with the biological system used to measure it. Radiobiological experiments indicate that 6,000 rads of radium gamma rays in seven days is equivalent to 890 rads of 252Cf neutrons delivered in approximately the same overall time. This figure was suggested some years ago as an interim guide-line until sufficient clinical experience is accumulated.

  16. Information on antiprotonic atoms and the nuclear periphery from the PS209 experiment

    CERN Document Server

    Trzcinska, A.; Czosnyka, T.; von Egidy, T.; Gulda, K.; Hartmann, F.J.; Iwanicki, J.; Ketzer, B.; Kisielinski, M.; Klos, B.; Kurcewicz, W.; Lubinski, P.; Napiorkowski, P.J.; Pienkowski, L.; Schmidt, R.; Widmann, E.

    2001-01-01

    In the PS209 experiments at CERN two kinds of measurements were performed: the in-beam measurement of X-rays from antiprotonic atoms and the radiochemical, off-line determination of the yield of annihilation products with mass number A_t -1 (less by 1 than the target mass). Both methods give observables which allows to study the peripheral matter density composition and distribution.

  17. The Bess Investigation of the Origin of Cosmic-ray Antiprotons and Search for Cosmological Antimatter

    Science.gov (United States)

    Mitchell, John; Yamamoto, Akira; Yoshimura, Koji; Makida, Yasuhiro; Matsuda, Shinya; Hasegawa, Masaya; Horikoshi, Atsushi; Tanaka,Ken-ichi; Suzuki, Junichi; Nishimura, Jun; hide

    2008-01-01

    The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has made precise measurements of the spectra of cosmic ray antiprotons and light nuclei and conducted a sensitive search for antinuclei. Ten BESS high-latitude flights, eight from Canada and two from Antarctica, span more than a Solar cycle between 1993 and 2007/2008. BESS measurements of low-energy antiprotons constrain candidate models for dark matter including the possible signature of primordial black hole evaporation. The stringent BESS measurements of antiprotons and the elemental and isotopic spectra of H and He provide strong constraints on models of cosmic-ray transport in the Galaxy and Solar System. BESS has also reported the first antideuterium upper limit. BESS employs a superconducting magnetic-rigity spectrometer with time-of-flight and aerogel Cherenkov detectors to identify incident particles by charge, charge sign, mass, and energy. The BESS-Polar long-duration instrument has reduced lower energy limit of 100 MeV (top of the atmosphere) to increase its sensitivity to possible primary antiproton sources. BESS-Polar II was rebuilt with extended magnet lifetime, improved detector and electronic performance, and greater data storage capacity. It was flown fro Antarctica December 2007-January 2008, recording about 4.6 bission events during 24.5 days at float altitude with the magnet on. During the flight the influence of a high-speed stream in the Solar wind was observed. Details of the BESS-Polar II instrument and flight performance are reported elsewhere at this conference. The successful BESS-Polar II flight at Solar minimum is especially important. Most cosmic-ray antiprotons are secondary products of nuclear interactions of primary cosmic-ray nuclei with the interstellar gas, giving a spectrum that peaks at about 2 GeV and falls rapidly to higher and lower energies. However, BESS data taken in the previous Solar minimum show a small excess over secondary

  18. Measurement and properties of the dose-area product ratio in external small-beam radiotherapy

    Science.gov (United States)

    Niemelä, Jarkko; Partanen, Mari; Ojala, Jarkko; Sipilä, Petri; Björkqvist, Mikko; Kapanen, Mika; Keyriläinen, Jani

    2017-06-01

    In small-beam radiation therapy (RT) the measurement of the beam quality parameter, i.e. the tissue-phantom ratio or TPR20,10, using a conventional point detector is a challenge. To obtain reliable results, one has to consider potential sources of error, including volume averaging and adjustment of the point detector into the narrow beam. To overcome these challenges, a different type of beam quality parameter in small beams was studied, namely the dose-area product ratio, or DAPR20,10. With this method, the measurement of a dose-area product (DAP) using a large-area plane-parallel chamber (LAC) eliminates the uncertainties in detector positioning and volume averaging that are present when using a point detector. In this study, the properties of the DAPR20,10 of a cone-collimated 6 MV photon beam were investigated using Monte Carlo (MC) calculations and the obtained values were compared to measurements obtained using two LAC detectors, PTW Type 34073 and PTW Type 34070. In addition, the possibility of determining the DAP using EBT3 film and a Razor diode detector was studied. The determination of the DAPR20,10 value was found to be feasible in external small-beam radiotherapy using cone-collimated beams with diameters from 4-40 mm, based on the results of the two LACs, the MC calculations and the Razor diode. The measurements indicated a constant DAPR20,10 value for fields 20-40 mm in diameter, with a maximum relative change of 0.6%, but an increase of 7.0% for fields from 20-4 mm in diameter for the PTW Type 34070 chamber. Simulations and measurements showed an increase of DAPR20,10 with increasing LAC size or dose integral area for the studied 4-40 mm cone-collimated 6 MV photon beams. This has the consequence that there should be a reference to the size of the used LAC active area or the DAP integration area with the reported DAPR20,10 value.

  19. Measurement and properties of the dose-area product ratio in external small-beam radiotherapy.

    Science.gov (United States)

    Niemelä, Jarkko; Partanen, Mari; Ojala, Jarkko; Sipilä, Petri; Björkqvist, Mikko; Kapanen, Mika; Keyriläinen, Jani

    2017-06-21

    In small-beam radiation therapy (RT) the measurement of the beam quality parameter, i.e. the tissue-phantom ratio or TPR 20,10 , using a conventional point detector is a challenge. To obtain reliable results, one has to consider potential sources of error, including volume averaging and adjustment of the point detector into the narrow beam. To overcome these challenges, a different type of beam quality parameter in small beams was studied, namely the dose-area product ratio, or DAPR 20,10 . With this method, the measurement of a dose-area product (DAP) using a large-area plane-parallel chamber (LAC) eliminates the uncertainties in detector positioning and volume averaging that are present when using a point detector. In this study, the properties of the DAPR 20,10 of a cone-collimated 6 MV photon beam were investigated using Monte Carlo (MC) calculations and the obtained values were compared to measurements obtained using two LAC detectors, PTW Type 34073 and PTW Type 34070. In addition, the possibility of determining the DAP using EBT3 film and a Razor diode detector was studied. The determination of the DAPR 20,10 value was found to be feasible in external small-beam radiotherapy using cone-collimated beams with diameters from 4-40 mm, based on the results of the two LACs, the MC calculations and the Razor diode. The measurements indicated a constant DAPR 20,10 value for fields 20-40 mm in diameter, with a maximum relative change of 0.6%, but an increase of 7.0% for fields from 20-4 mm in diameter for the PTW Type 34070 chamber. Simulations and measurements showed an increase of DAPR 20,10 with increasing LAC size or dose integral area for the studied 4-40 mm cone-collimated 6 MV photon beams. This has the consequence that there should be a reference to the size of the used LAC active area or the DAP integration area with the reported DAPR 20,10 value.

  20. Investigation of silicon sensors for their use as antiproton annihilation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Pacifico, N., E-mail: nicola.pacifico@cern.ch [University of Bergen, Institute of Physics and Technology, Allégaten 55, 5007 Bergen (Norway); Aghion, S. [Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sez. di Milano, Via Celoria 16, 20133 Milano (Italy); Ahlén, O. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Belov, A.S. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow 117312 (Russian Federation); Bonomi, G. [University of Brescia, Department of Mechanical and Industrial Engineering, Via Branze 38, 25133 Brescia (Italy); Istituto Nazionale di Fisica Nucleare, Sez. di Pavia, Via Agostino Bassi 6, 27100 Pavia (Italy); Bräunig, P. [Kirchhoff Institute for Physics, Im Neuenheimer Feld 227, 69120 Heidelberg (Germany); Bremer, J. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Brusa, R.S. [Department of Physics, University of Trento, via Sommarive 14, 38123 Povo, Trento (Italy); INFN-TIFPA, via Sommarive 14, 38123 Povo, Trento (Italy); Burghart, G. [European Organisation for Nuclear Research, Physics Department, 1211 Geneva 23 (Switzerland); Cabaret, L. [Laboratoire Aimé Cotton, CNRS, Université Paris Sud, ENS Cachan, Bâtiment 505, Campus d' Orsay, 91405 Orsay Cedex (France); Caccia, M. [University of Insubria, Dipartimento di Scienza ed Alta Tecnologia, via Valleggio 11, Como (Italy); Canali, C. [University of Zurich, Physics Institute, Winterthurerstrasse 190, 8057 Zurich (Switzerland); Caravita, R. [Istituto Nazionale di Fisica Nucleare, Sez. di Genova, Via Dodecaneso 33, 16146 Genova (Italy); University of Genoa, Department of Physics, Via Dodecaneso 33, 16146 Genova (Italy); Castelli, F. [University of Milano, Department of Physics, Via Celoria 16, 20133 Milano (Italy); and others

    2014-11-21

    We present here a new application of silicon sensors aimed at the direct detection of antinucleons annihilations taking place inside the sensor's volume. Such detectors are interesting particularly for the measurement of antimatter properties and will be used as part of the gravity measurement module in the AEg{sup ¯}IS experiment at the CERN Antiproton Decelerator. One of the goals of the AEg{sup ¯}IS experiment is to measure the gravitational acceleration of antihydrogen with 1% precision. Three different silicon sensor geometries have been tested with an antiproton beam to investigate their properties as annihilation detection devices: strip planar, 3D pixels and monolithic pixel planar. In all cases we were successfully detecting annihilations taking place in the sensor and we were able to make a first characterization of the clusters and tracks.

  1. Buffer-gas cooling of antiprotonic helium to 1.5 to 1.7 K, and antiproton-to–electron mass ratio

    CERN Document Server

    Hori, Masaki; Sótér, Anna; Barna, Daniel; Dax, Andreas; Hayano, Ryugo; Kobayashi, Takumi; Murakami, Yohei; Todoroki, Koichi; Yamada, Hiroyuki; Horváth, Dezső; Venturelli, Luca

    2016-01-01

    Charge, parity, and time reversal (CPT) symmetry implies that a particle and its antiparticle have the same mass. The antiproton-to-electron mass ratio Embedded Image can be precisely determined from the single-photon transition frequencies of antiprotonic helium. We measured 13 such frequencies with laser spectroscopy to a fractional precision of 2.5 × 10−9 to 16 × 10−9. About 2 × 109 antiprotonic helium atoms were cooled to temperatures between 1.5 and 1.7 kelvin by using buffer-gas cooling in cryogenic low-pressure helium gas; the narrow thermal distribution led to the observation of sharp spectral lines of small thermal Doppler width. The deviation between the experimental frequencies and the results of three-body quantum electrodynamics calculations was reduced by a factor of 1.4 to 10 compared with previous single-photon experiments. From this, Embedded Image was determined as 1836.1526734(15), which agrees with a recent proton-to-electron experimental value within 8 × 10−10.

  2. Antiproton-Proton Glory Scattering

    CERN Multimedia

    2002-01-01

    This experiment measures @*p and K|-p backwards scattering between 8 and 16 GeV/c in the Omega spectrometer using the S1 beam, with sensitivities of several events per nanobarn. The mechanism responsible for backward scattering in channels not mediated by particle exchange is not understood, and could be almost energy-independent glory scattering, especially since relatively high cross sections of 190~(@*p) and 120~(K|-p)nb have been measured earlier at 5~GeV/c. @p|-p backwards scattering is measured for monitoring purposes. The trigger requires a forward particle of momentum close to the beam momentum. Absence of light in the two forward Cerenkov counters indicates that the particle is a proton. Combinations of an incident @p|- and an outgoing K|+, or an incident K|- or @* and an outgoing @p|+, cover the following byproducts: @*p~@A~@p|+@p|- which is an (allowed) baryon exchange reaction, and the exotic exchange reactions @p|-p~@A~K|+Y K|-p~@A~@p|+Y|-, where Y|- may be the @S|- or the Y*|-(1385).

  3. LEAP [Low-Energy Antiproton]: A balloon-borne search for low-energy cosmic-ray antiprotons

    International Nuclear Information System (INIS)

    Moats, A.R.M.

    1989-01-01

    The LEAP (Low-Energy Antiproton) experiment is a search for cosmic-ray antiprotons in the 120 MeV to 1.2 GeV kinetic energy range. The motivation for this project was the result announced by Buffington et. al. (1981) that indicated an anomalously high antiproton flux below 300 MeV; this result has compelled theorists to propose sources of primary antiprotons above the small secondary antiproton flux produced by high energy cosmic-ray collisions with nuclei in the interstellar medium. LEAP consisted of the NMSU magnetic spectrometer, a time-of-flight system designed at Goddard Space Flight Center, two scintillation detectors, and a Cherenkov counter designed and built at the University of Arizona. Analysis of flight data performed by the high-energy astrophysics group at Goddard Space Flight Center revealed no antiproton candidates found in the 120 MeV to 360 MeV range; 3 possible antiproton candidate events were found in the 500 MeV to 1.2 GeV range in an analysis done here at the University of Arizona. However, since it will be necessary to sharpen the calibration on all of the LEAP systems in order to positively identify these events as antiprotons, only an upper limit has been determined at present. Thus, combining the analyses performed at the University of Arizona and Goddard Space Flight Center, 90% confidence upper limits of 3.5 x 10 -5 in the 120 MeV to 360 MeV range and 2.3 x 10 -4 in the 500 MeV to 1.2 GeV range for the antiproton/proton ratio is indicated by the LEAP results. LEAP disagrees sharply with the results of the Buffington group, indicating a low antiproton flux at these energies

  4. Compact source origin of cosmic ray antiprotons

    International Nuclear Information System (INIS)

    Dermer, C.D.

    1989-02-01

    The flux of cosmic ray antiprotons with kinetic energies between /approximately/1 and 15 GeV is /approximately/5 times greater than the flux predicted on the basis of the leaky-box model. This excess is attributed to secondary antineutron production in compact sources. Because the antineutrons are not confined by the magnetic field of the compact source, they leave the interaction site, decay in interstellar space and account for the apparent excess cosmic ray antiproton flux. The escape and decay of neutrons produced in association with the antineutrons is a source of cosmic ray protons. Observations of the angular variation of the intensity and spectral shape of 100 MeV γ-rays produced by neutron-decay protons in the reaction p + p → π 0 → 2γ could reveal compact-source cosmic ray production sites. COS-B observations of spectral hardening near point sources, and future high-resolution observations of galactic point sources by Gamma-1 and the Egret telescope onboard the Gamma Ray Observatory may provide supporting evidence for this model. 12 refs., 2 figs

  5. Development of a monoenergetic ultraslow antiproton beam source for high-precision investigation

    Directory of Open Access Journals (Sweden)

    N. Kuroda

    2012-02-01

    Full Text Available The ASACUSA collaboration developed an ultraslow antiproton beam source, monoenergetic ultraslow antiproton source for high-precision investigation (MUSASHI, consisting of an electromagnetic trap with a liquid He free superconducting solenoid and a low energy antiproton beam transport line. The MUSASHI was capable of trapping and cooling more than 1×10^{7} antiprotons and extracting them as an ultraslow antiproton beam with energy of 150–250 eV.

  6. Secondary emission monitor for keV ion and antiproton beams

    CERN Document Server

    Sosa, Alejandro; Bravin, Enrico; Harasimowciz, Janusz; Welsch, C P

    2013-01-01

    Beam profile monitoring of low intensity keV ion and antiproton beams remains a challenging task. A Sec- ondary electron Emission Monitor (SEM) has been de- signed to measure profiles of beams with intensities below 107 and energies as low as 20 keV. The monitor is based on a two stage microchannel plate (MCP) and a phosphor screen facing a CCD camera. Its modular design allows two different operational setups. In this contribution we present the design of a prototype and discuss results from measurements with antiprotons at the AEgIS experiment at CERN. This is then used for a characterization of the monitor with regard to its possible future use at different facilities.

  7. An experimental lower limit on the antiproton lifetime

    Directory of Open Access Journals (Sweden)

    S.N. Ganguli

    1978-03-01

    Full Text Available A search for the possible decay of the antiproton has been carried out in a hydrogen bubble chamber exposed to a 0.76 GeV/c antiproton beam. As a result 161 odd-prong events with a net charge of −1 in the final state were observed. After subtracting the two types of background discussed in the paper we are left with a signal of 5 ± 16 events. From this a lower limit of 1.2 X 10−4s has been obtained for the antiproton lifetime with 95% confidence level.

  8. Proton - antiproton annihilations to φφ mesons: results from JETSET at LEAR

    Science.gov (United States)

    Bertolotto, L.; Buzzo, A.; Debevec, P. T.; Drijard, D.; Easo, S.; Eisenstein, R. A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Franz, J.; Geyer, R.; Hamann, N.; Harris, Ph.; Hertzog, D. W.; Hughes, S. A.; Johansson, T.; Jones, R.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Marinelli, M.; Moossburger, M.; Mouëllic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J. M.; Pia, M. G.; Pozzo, A.; Price, M.; Reimer, P. E.; Ritter, J.; Robutti, E.; Röhrich, K.; Rook, M.; Rössle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tscheulin, M.; Urban, H. J.; Wirth, H.; Zipse, H.; Jetset Collaboration

    1993-06-01

    The πp → φφ reaction has been studied in an internal target experiment at LEAR using antiprotons at various laboratory momenta spanning the region between 1 and 2 GeV/c (cms energies between 2.08 and 2.43 GeV). Cross sections have been measured at a total of 16 different energy settings over the above range. Preliminary cross sections are reported.

  9. Proton-antiproton annihilations to [phi][phi]mesons: results from JETSET at LEAR

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, L.; Buzzo, A.; Devevec, P.T.; Drijard, D.; Easo, S.; Eisenstein, R.A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Franz, J.; Geyer, R.; Hamann, N.; Harris, P.; Hertzog, D.W.; Hughes, S.A.; Johansson, T.; Jones, R.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Marinelli, M.; Moossburger, M.; Mouellic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J.M.; Pia, M.G.; Pozzo, A.; Price, M.; Reimer, P.E.; Ritter, J.; Robutti, E.; Roehrich, K.; Rook, M.; Roessle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tscheulin, M.; Urban, H.J.; Wirth, H.; Zipse, H. (Istituto Nazionale di Fisica Nucleare, Genoa (Italy) Genoa Univ. (Italy) Univ. of Illinois, Urbana-Champaign (United States) European Organization for Nuclear Research (CERN), Geneva (Switzerland) Istituto Nazionale di Fisica Nucleare, Bari (Italy) Bari Univ. (Italy) Physikalisches Institut, Erlangen Univ. (Germany) Fakultaet fuer Physik, Univ. Freib; JETSET Collaboration

    1993-06-07

    The [pi]p[yields][phi][phi] reaction has been studied in an internal target experiment at LEAR using antiprotons at various laboratory momenta spanning the region between 1 and 2 GeV/c (cms energies between 2.08 and 2.43 GeV). Cross sections have been measured at a total of 16 different energy settings over the above range. Preliminary cross sections are reported. (orig.)

  10. Proton-antiproton annihilations to φφmesons: results from JETSET at LEAR

    International Nuclear Information System (INIS)

    Bertolotto, L.; Buzzo, A.; Devevec, P.T.; Drijard, D.; Easo, S.; Eisenstein, R.A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Franz, J.; Geyer, R.; Hamann, N.; Harris, P.; Hertzog, D.W.; Hughes, S.A.; Johansson, T.; Jones, R.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Marinelli, M.; Moossburger, M.; Mouellic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J.M.; Pia, M.G.; Pozzo, A.; Price, M.; Reimer, P.E.; Ritter, J.; Robutti, E.; Roehrich, K.; Rook, M.; Roessle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tscheulin, M.; Urban, H.J.; Wirth, H.; Zipse, H.

    1993-01-01

    The πp→φφ reaction has been studied in an internal target experiment at LEAR using antiprotons at various laboratory momenta spanning the region between 1 and 2 GeV/c (cms energies between 2.08 and 2.43 GeV). Cross sections have been measured at a total of 16 different energy settings over the above range. Preliminary cross sections are reported. (orig.)

  11. MRI-based measurements of respiratory motion variability and assessment of imaging strategies for radiotherapy planning

    Science.gov (United States)

    Blackall, J. M.; Ahmad, S.; Miquel, M. E.; McClelland, J. R.; Landau, D. B.; Hawkes, D. J.

    2006-09-01

    Respiratory organ motion has a significant impact on the planning and delivery of radiotherapy (RT) treatment for lung cancer. Currently widespread techniques, such as 4D-computed tomography (4DCT), cannot be used to measure variability of this motion from one cycle to the next. In this paper, we describe the use of fast magnetic resonance imaging (MRI) techniques to investigate the intra- and inter-cycle reproducibility of respiratory motion and also to estimate the level of errors that may be introduced into treatment delivery by using various breath-hold imaging strategies during lung RT planning. A reference model of respiratory motion is formed to enable comparison of different breathing cycles at any arbitrary position in the respiratory cycle. This is constructed by using free-breathing images from the inhale phase of a single breathing cycle, then co-registering the images, and thereby tracking landmarks. This reference model is then compared to alternative models constructed from images acquired during the exhale phase of the same cycle and the inhale phase of a subsequent cycle, to assess intra- and inter-cycle variability ('hysteresis' and 'reproducibility') of organ motion. The reference model is also compared to a series of models formed from breath-hold data at exhale and inhale. Evaluation of these models is carried out on data from ten healthy volunteers and five lung cancer patients. Free-breathing models show good levels of intra- and inter-cycle reproducibility across the tidal breathing range. Mean intra-cycle errors in the position of organ surface landmarks of 1.5(1.4)-3.5(3.3) mm for volunteers and 2.8(1.8)-5.2(5.2) mm for patients. Equivalent measures of inter-cycle variability across this range are 1.7(1.0)-3.9(3.3) mm for volunteers and 2.8(1.8)-3.3(2.2) mm for patients. As expected, models based on breath-hold sequences do not represent normal tidal motion as well as those based on free-breathing data, with mean errors of 4

  12. A new transmission methodology for quality assurance in radiotherapy based on radiochromic film measurements

    Science.gov (United States)

    do Amaral, Leonardo L.; Pavoni, Juliana F.; Sampaio, Francisco; Netto, Thomaz Ghilardi

    2015-01-01

    Despite individual quality assurance (QA) being recommended for complex techniques in radiotherapy (RT) treatment, the possibility of errors in dose delivery during therapeutic application has been verified. Therefore, it is fundamentally important to conduct in vivo QA during treatment. This work presents an in vivo transmission quality control methodology, using radiochromic film (RCF) coupled to the linear accelerator (linac) accessory holder. This QA methodology compares the dose distribution measured by the film in the linac accessory holder with the dose distribution expected by the treatment planning software. The calculated dose distribution is obtained in the coronal and central plane of a phantom with the same dimensions of the acrylic support used for positioning the film but in a source‐to‐detector distance (SDD) of 100 cm, as a result of transferring the IMRT plan in question with all the fields positioned with the gantry vertically, that is, perpendicular to the phantom. To validate this procedure, first of all a Monte Carlo simulation using PENELOPE code was done to evaluate the differences between the dose distributions measured by the film in a SDD of 56.8 cm and 100 cm. After that, several simple dose distribution tests were evaluated using the proposed methodology, and finally a study using IMRT treatments was done. In the Monte Carlo simulation, the mean percentage of points approved in the gamma function comparing the dose distribution acquired in the two SDDs were 99.92%±0.14%. In the simple dose distribution tests, the mean percentage of points approved in the gamma function were 99.85%±0.26% and the mean percentage differences in the normalization point doses were −1.41%. The transmission methodology was approved in 24 of 25 IMRT test irradiations. Based on these results, it can be concluded that the proposed methodology using RCFs can be applied for in vivo QA in RT treatments. PACS number: 87.55.Qr, 87.55.km, 87.55.N‐ PMID

  13. Measurement of time delays in gated radiotherapy for realistic respiratory motions

    Energy Technology Data Exchange (ETDEWEB)

    Chugh, Brige P.; Quirk, Sarah; Conroy, Leigh; Smith, Wendy L., E-mail: Wendy.Smith@albertahealthservices.ca [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta T2N 4N2 (Canada)

    2014-09-15

    Purpose: Gated radiotherapy is used to reduce internal motion margins, escalate target dose, and limit normal tissue dose; however, its temporal accuracy is limited. Beam-on and beam-off time delays can lead to treatment inefficiencies and/or geographic misses; therefore, AAPM Task Group 142 recommends verifying the temporal accuracy of gating systems. Many groups use sinusoidal phantom motion for this, under the tacit assumption that use of sinusoidal motion for determining time delays produces negligible error. The authors test this assumption by measuring gating time delays for several realistic motion shapes with increasing degrees of irregularity. Methods: Time delays were measured on a linear accelerator with a real-time position management system (Varian TrueBeam with RPM system version 1.7.5) for seven motion shapes: regular sinusoidal; regular realistic-shape; large (40%) and small (10%) variations in amplitude; large (40%) variations in period; small (10%) variations in both amplitude and period; and baseline drift (30%). Film streaks of radiation exposure were generated for each motion shape using a programmable motion phantom. Beam-on and beam-off time delays were determined from the difference between the expected and observed streak length. Results: For the system investigated, all sine, regular realistic-shape, and slightly irregular amplitude variation motions had beam-off and beam-on time delays within the AAPM recommended limit of less than 100 ms. In phase-based gating, even small variations in period resulted in some time delays greater than 100 ms. Considerable time delays over 1 s were observed with highly irregular motion. Conclusions: Sinusoidal motion shapes can be considered a reasonable approximation to the more complex and slightly irregular shapes of realistic motion. When using phase-based gating with predictive filters even small variations in period can result in time delays over 100 ms. Clinical use of these systems for patients

  14. Measurement of time delays in gated radiotherapy for realistic respiratory motions

    International Nuclear Information System (INIS)

    Chugh, Brige P.; Quirk, Sarah; Conroy, Leigh; Smith, Wendy L.

    2014-01-01

    Purpose: Gated radiotherapy is used to reduce internal motion margins, escalate target dose, and limit normal tissue dose; however, its temporal accuracy is limited. Beam-on and beam-off time delays can lead to treatment inefficiencies and/or geographic misses; therefore, AAPM Task Group 142 recommends verifying the temporal accuracy of gating systems. Many groups use sinusoidal phantom motion for this, under the tacit assumption that use of sinusoidal motion for determining time delays produces negligible error. The authors test this assumption by measuring gating time delays for several realistic motion shapes with increasing degrees of irregularity. Methods: Time delays were measured on a linear accelerator with a real-time position management system (Varian TrueBeam with RPM system version 1.7.5) for seven motion shapes: regular sinusoidal; regular realistic-shape; large (40%) and small (10%) variations in amplitude; large (40%) variations in period; small (10%) variations in both amplitude and period; and baseline drift (30%). Film streaks of radiation exposure were generated for each motion shape using a programmable motion phantom. Beam-on and beam-off time delays were determined from the difference between the expected and observed streak length. Results: For the system investigated, all sine, regular realistic-shape, and slightly irregular amplitude variation motions had beam-off and beam-on time delays within the AAPM recommended limit of less than 100 ms. In phase-based gating, even small variations in period resulted in some time delays greater than 100 ms. Considerable time delays over 1 s were observed with highly irregular motion. Conclusions: Sinusoidal motion shapes can be considered a reasonable approximation to the more complex and slightly irregular shapes of realistic motion. When using phase-based gating with predictive filters even small variations in period can result in time delays over 100 ms. Clinical use of these systems for patients

  15. MRI-based measurements of respiratory motion variability and assessment of imaging strategies for radiotherapy planning

    International Nuclear Information System (INIS)

    Blackall, J M; Ahmad, S; Miquel, M E; McClelland, J R; Landau, D B; Hawkes, D J

    2006-01-01

    Respiratory organ motion has a significant impact on the planning and delivery of radiotherapy (RT) treatment for lung cancer. Currently widespread techniques, such as 4D-computed tomography (4DCT), cannot be used to measure variability of this motion from one cycle to the next. In this paper, we describe the use of fast magnetic resonance imaging (MRI) techniques to investigate the intra- and inter-cycle reproducibility of respiratory motion and also to estimate the level of errors that may be introduced into treatment delivery by using various breath-hold imaging strategies during lung RT planning. A reference model of respiratory motion is formed to enable comparison of different breathing cycles at any arbitrary position in the respiratory cycle. This is constructed by using free-breathing images from the inhale phase of a single breathing cycle, then co-registering the images, and thereby tracking landmarks. This reference model is then compared to alternative models constructed from images acquired during the exhale phase of the same cycle and the inhale phase of a subsequent cycle, to assess intra- and inter-cycle variability ('hysteresis' and 'reproducibility') of organ motion. The reference model is also compared to a series of models formed from breath-hold data at exhale and inhale. Evaluation of these models is carried out on data from ten healthy volunteers and five lung cancer patients. Free-breathing models show good levels of intra- and inter-cycle reproducibility across the tidal breathing range. Mean intra-cycle errors in the position of organ surface landmarks of 1.5(1.4)-3.5(3.3) mm for volunteers and 2.8(1.8)-5.2(5.2) mm for patients. Equivalent measures of inter-cycle variability across this range are 1.7(1.0)-3.9(3.3) mm for volunteers and 2.8(1.8)-3.3(2.2) mm for patients. As expected, models based on breath-hold sequences do not represent normal tidal motion as well as those based on free-breathing data, with mean errors of 4

  16. A Cryogenic Current Comparator for the Low Energy Antiproton Facilities at CERN

    CERN Document Server

    Fernandes, M; Welsch, CP

    2014-01-01

    Several laboratories have shown the potential of using Superconducting QUantum Interference Device (SQUID) magnetometers together with superconductor magnetic shields to measure beam current intensities in the submicro-Ampere regime. CERN, in collaboration with GSI, Jena university and Helmholtz Institute Jena, is currently working on developing an improved version of such a current monitor for the Antiproton Decelerator (AD) and Extra Low ENergy Antiproton (ELENA) rings at CERN, aiming for better current resolution and overall system availability. This contribution will present the current design, including theoretical estimation of the current resolution; stability limits of SQUID systems and adaptation of the coupling circuit to the AD beam parameters; the analysis of thermal and mechanical cryostat modes.

  17. Suppression of propagating TE modes in the FNAL antiproton source stochastic beam cooling system

    International Nuclear Information System (INIS)

    Barry, W.C.

    1985-05-01

    A method of attenuating the propagation of waveguide modes in the stochastic cooling array beam pipes to be utilized in the accumulator and debuncher rings of the Fermilab antiproton source is described. The attenuation method treated involves lining the vertical walls of the beam pipes with a ferrimagnetic material. The general solution for propagation in a nonhomogeneously loaded waveguide is presented along with numerical results specific to the antiproton source beam cooling system. Also described is a broadband, automated technique for the simultaneous measurement of complex μ and epsilon developed to aid in the characterization of different ferrite materials. Permittivity and permeability data for a typical ferrite are presented along with a discussion of the effects of these parameters on waveguide mode attenuation in the ferrite lined beam pipes

  18. Role of perfusion SPECT in prediction and measurement of pulmonary complications after radiotherapy for lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Farr, Katherina P.; Khalil, Azza A.; Grau, Cai [Aarhus University Hospital, Department of Oncology, Aarhus C (Denmark); Kramer, Stine; Morsing, Anni [Aarhus University Hospital, Department of Nuclear Medicine and PET Centre, Aarhus C (Denmark)

    2015-07-15

    The purpose of the study was to evaluate the ability of baseline perfusion defect score (DS) on SPECT to predict the development of severe symptomatic radiation pneumonitis (RP) and to evaluate changes in perfusion on SPECT as a method of lung perfusion function assessment after curative radiotherapy (RT) for non-small-cell lung cancer (NSCLC). Patients with NSCLC undergoing curative RT were included prospectively. Perfusion SPECT/CT and global pulmonary function tests (PFT) were performed before RT and four times during follow-up. Functional activity on SPECT was measured using a semiquantitative perfusion DS. Pulmonary morbidity was graded by the National Cancer Institute's Common Terminology Criteria for Adverse Events version 4 for pneumonitis. Patients were divided into two groups according to the severity of RP. A total of 71 consecutive patients were included in the study. Baseline DS was associated with chronic obstructive pulmonary disease. A significant inverse correlation was found between baseline DS and forced expiratory volume in 1 s and diffusing capacity of the lung for carbon monoxide. Patients with severe RP had significantly higher baseline total lung DS (mean 5.43) than those with no or mild symptoms (mean DS 3.96, p < 0.01). PFT results were not different between these two groups. The odds ratio for total lung DS was 7.8 (95 % CI 1.9 - 31) demonstrating the ability of this parameter to predict severe RP. Adjustment for other potential confounders known to be associated with increased risk of RP was performed and did not change the odds ratio. The median follow-up time after RT was 8.4 months. The largest DS increase of 13.3 % was associated with severe RP at 3 months of follow-up (p < 0.01). The development of severe RP during follow-up was not associated with changes in PFT results. Perfusion SPECT is a valuable method for predicting severe RP and for assessing changes in regional functional perfusion after curative RT comparable with

  19. Prospects for antiproton physics, my perspective

    International Nuclear Information System (INIS)

    Oelert, Walter

    2012-01-01

    These closing remarks are not supposed to be a summary talk, for this please have a look to the individual contributions to be published in the proceedings, but rather some considerations on future prospects for antiproton physics. However, first I would like to appreciate the organizers idea for giving me the opportunity to thank them for a well balanced, exciting and interesting conference LEAP-2011 in this marvelous city of Vancouver. I am sure we all loved to be here and enjoyed the hospitality and the bond of friendship we could experience during these days. We appreciate the patience and help of all the local organizers where I especially would like to mention Jana Thomson for her endless and helpful assignment. Thank you all—the participants, the speakers, the conference chair, the sponsors—for making this conference a success and we are looking forward to the next occasion in this series of meetings which will be celebrated in Uppsala.

  20. ''Antiflow'' of antiprotons in heavy ion collisions

    International Nuclear Information System (INIS)

    Jahns, A.; Spieles, C.; Sorge, H.; Stoecker, H.; Greiner, W.

    1994-01-01

    In the framework of the relativistic quantum molecular dynamics approach we investigate antiproton (bar p) observables in Au+Au collisions at 10.7A GeV. The rapidity dependence of the in-plane directed transverse momentum p x (y) of bar p's shows the opposite sign of the nucleon flow, which has indeed recently been discovered at 10.7A GeV by the E877 group. The ''antiflow'' of bar p's is also predicted at 2A GeV and at 160A GeV and appears at all energies also for π's and K - 's. These predicted bar p anticorrelations are a direct proof of strong bar p annihilation in massive heavy ion reactions

  1. Antiproton cell experiment: antimatter is a better killer

    CERN Multimedia

    2006-01-01

    "European Organization for Nuclear Research is reporting that results from a three year study of antiprotons for neoplasm irrdiation showed a better cellular killer with a smaller lethal dose." (1,5 page)

  2. Energy Dependence of Measured CT Numbers on Substituted Materials Used for CT Number Calibration of Radiotherapy Treatment Planning Systems.

    Directory of Open Access Journals (Sweden)

    Reza Mahmoudi

    Full Text Available For accurate dose calculations, it is necessary to provide a correct relationship between the CT numbers and electron density in radiotherapy treatment planning systems (TPSs. The purpose of this study was to investigate the energy dependence of measured CT numbers on substituted materials used for CT number calibration of radiotherapy TPSs and the resulting errors in the treatment planning calculation doses.In this study, we designed a cylindrical water phantom with different materials used as tissue equivalent materials for the simulation of tissues and obtaining the related CT numbers. For evaluating the effect of CT number variations of substituted materials due to energy changing of scanner (kVp on the dose calculation of TPS, the slices of the scanned phantom at three kVp's were imported into the desired TPSs (MIRS and CorePLAN. Dose calculations were performed on two TPSs.The mean absolute percentage differences between the CT numbers of CT scanner and two treatment planning systems for all the samples were 3.22%±2.57% for CorePLAN and 2.88%±2.11% for MIRS. It was also found that the maximum absolute percentage difference between all of the calculated doses from each photon beam of linac (6 and 15 MV at three kVp's was less than 1.2%.The present study revealed that, for the materials with effective low atomic number, the mean CT number increased with increasing energy, which was opposite for the materials with an effective high atomic number. We concluded that the tissue substitute materials had a different behavior in the energy ranges from 80 to 130 kVp. So, it is necessary to consider the energy dependence of the substitute materials used for the measurement or calibration of CT number for radiotherapy treatment planning systems.

  3. Measurements of the top quark pair production cross section in lepton+jets final states using a topological multivariate technique as well as lifetime b-tagging in proton-antiproton collisions at √(s)=1.96 TeV with the DOe detector at the Tevatron

    International Nuclear Information System (INIS)

    Golling, T.

    2005-01-01

    Two alternative measurements of the tt production cross section at √(s)=1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The tt production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields σ p anti p→t anti t+X = 5.13 -1.57 +1.76 (stat) -1.10 +0.96 (syst) ±0.33 (lumi) pb in the muon+jets channel, using 229.1 pb -1 , and in the combination with the electron+jets channel (226.3 pb -1 ) σ p anti p→t anti t +X = 6.60 -1.28 +1.37 (stat) -1.11 +1.25 (syst) ± 0.43 (lumi) pb. The second measurement presented reconstructs explicitly secondary vertices to do lifetime b-tagging. The measurement combines the muon+jets and the electron+jets channel, using 158.4 pb -1 and 168.8 pb -1 , respectively: σ p anti p→t anti t+X = 8.24 -1.25 +1.34 (stat) -1.63 +1.89 (syst) ± 0.54 (lumi) pb. (orig.)

  4. Development of a diamond dosimeter for measuring the absorbed dose in small beams used in stereotactic radiotherapy

    International Nuclear Information System (INIS)

    Marsolat, F.

    2014-01-01

    Stereotactic radiotherapy is a relatively recent technique used for the treatment of small benign and malignant tumors with small radiation beams. The clinical efficiency of this technique has been proved. However, the measurement of absolute and relative dose in small beams is not possible currently due to the lack of suited detectors for these measurements. In small beam dosimetry, the detector has to be as close as possible to tissue equivalence and exhibit a small detection volume due to the lack of lateral electronic equilibrium. Characteristics of diamond (water equivalent material Z=6, high density) make it an ideal candidate to fulfil most of small beam dosimetry requirements. In this thesis, we developed a dosimeter prototype for small beams, based on CVD synthetic single crystal diamond. The diamond samples were characterized optically and their detection properties were investigated under X-rays and alpha-particles. First diamond dosimeter prototypes were tested with small beams produced by several stereotactic machines. Studies using Monte Carlo simulations were performed in order to optimize the parameters involved in the detector response in small beams. This leaded to a final diamond dosimeter prototype that respects all radiotherapy centers requirements, in both standard and small beams. (author) [fr

  5. The magnetic moments of the proton and the antiproton

    CERN Document Server

    Ulmer, S.; Blaum, K.; Braeuninger, S.; Franke, K.; Kracke, H.; Leiteritz, C.; Matsuda, Y.; Nagahama, H.; Ospelkaus, C.; Rodegheri, C.C.; Quint, W.; Schneider, G.; Smorra, C.; Van Gorp, S.; Walz, J.; Yamazaki, Y.

    2014-01-01

    Recent exciting progress in the preparation and manipulation of the motional quantum states of a single trapped proton enabled the first direct detection of the particle's spin state. Based on this success the proton magnetic moment $\\mu_p$ was measured with ppm precision in a Penning trap with a superimposed magnetic field inhomogeneity. An improvement by an additional factor of 1000 in precision is possible by application of the so-called double Penning trap technique. In a recent paper we reported the first demonstration of this method with a single trapped proton, which is a major step towards the first direct high-precision measurement of $\\mu_p$. The techniques required for the proton can be directly applied to measure the antiproton magnetic moment $\\mu_{\\bar{p}}$. An improvement in precision of $\\mu_{\\bar{p}}$ by more than three orders of magnitude becomes possible, which will provide one of the most sensitive tests of CPT invariance. To achieve this research goal we are currently setting up the Baryo...

  6. Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p-Pb collisions at $\\sqrt{s_{\\rm NN}}$= 5.02 TeV

    CERN Document Server

    Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahmad, Shakeel; Ahn, Sang Un; Aiola, Salvatore; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Millan Almaraz, Jesus Roberto; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Arnaldi, Roberta; Arnold, Oliver Werner; Arsene, Ionut Cristian; Arslandok, Mesut; Audurier, Benjamin; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Balasubramanian, Supraja; Baldisseri, Alberto; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Barth, Klaus; Bartke, Jerzy Gustaw; Bartsch, Esther; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batista Camejo, Arianna; Batyunya, Boris; Batzing, Paul Christoph; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Belmont Iii, Ronald John; Belmont Moreno, Ernesto; Belyaev, Vladimir; Benacek, Pavel; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhat, Inayat Rasool; Bhati, Ashok Kumar; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biro, Gabor; Biswas, Rathijit; Biswas, Saikat; Bjelogrlic, Sandro; Blair, Justin Thomas; Blau, Dmitry; Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botta, Elena; Bourjau, Christian; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Bashir Butt, Jamila; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Carnesecchi, Francesca; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Ceballos Sanchez, Cesar; Cerello, Piergiorgio; Cerkala, Jakub; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chauvin, Alex; Chelnokov, Volodymyr; Cherney, Michael Gerard; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Cho, Soyeon; Chochula, Peter; Choi, Kyungeon; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Connors, Megan Elizabeth; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Crochet, Philippe; Cruz Albino, Rigoberto; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Danisch, Meike Charlotte; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Conti, Camila; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; Deplano, Caterina; Dhankher, Preeti; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Drozhzhova, Tatiana; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Endress, Eric; Engel, Heiko; Epple, Eliane; Erazmus, Barbara Ewa; Erdemir, Irem; Erhardt, Filip; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Eyyubova, Gyulnara; Fabbietti, Laura; Fabris, Daniela; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Feuillard, Victor Jose Gaston; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Fleck, Martin Gabriel; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fronze, Gabriele Gaetano; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Gao, Chaosong; Garabatos Cuadrado, Jose; Garcia-Solis, Edmundo Javier; Gargiulo, Corrado; Gasik, Piotr Jan; Gauger, Erin Frances; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez Coral, Diego Mauricio; Gomez Ramirez, Andres; Gonzalez, Victor; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Grachov, Oleg Anatolievich; Graczykowski, Lukasz Kamil; Graham, Katie Leanne; Grelli, Alessandro; Grigoras, Alina Gabriela; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Grynyov, Borys; Grion, Nevio; Gronefeld, Julius Maximilian; Grosse-Oetringhaus, Jan Fiete; Grossiord, Jean-Yves; Grosso, Raffaele; Guber, Fedor; Guernane, Rachid; Guerzoni, Barbara; Gulbrandsen, Kristjan Herlache; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Haake, Rudiger; Haaland, Oystein Senneset; Hadjidakis, Cynthia Marie; Haiduc, Maria; Hamagaki, Hideki; Hamar, Gergoe; Hamon, Julien Charles; Harris, John William; Harton, Austin Vincent; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Herrera Corral, Gerardo Antonio; Hess, Benjamin Andreas; Hetland, Kristin Fanebust; Hillemanns, Hartmut; Hippolyte, Boris; Horak, David; Hosokawa, Ritsuya; Hristov, Peter Zahariev; Huang, Meidana; Humanic, Thomas; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Ilkaev, Radiy; Inaba, Motoi; Incani, Elisa; Ippolitov, Mikhail; Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacazio, Nicolo; Jacobs, Peter Martin; Jadhav, Manoj Bhanudas; Jadlovska, Slavka; Jadlovsky, Jan; Jahnke, Cristiane; Jakubowska, Monika Joanna; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karayan, Lilit; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Do Won; Kim, Dong Jo; Kim, Daehyeok; Kim, Hyeonjoong; Kim, Jinsook; Kim, Minwoo; Kim, Se Yong; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Kiss, Gabor; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-Boesing, Christian; Klewin, Sebastian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobdaj, Chinorat; Kofarago, Monika; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kopcik, Michal; Kostarakis, Panagiotis; Kour, Mandeep; Kouzinopoulos, Charalampos; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Koyithatta Meethaleveedu, Greeshma; Kralik, Ivan; Kravcakova, Adela; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kumar, Ajay; Kumar, Jitendra; Lokesh, Kumar; Kumar, Shyam; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Ladron De Guevara, Pedro; Lagana Fernandes, Caio; Lakomov, Igor; Langoy, Rune; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Lattuca, Alessandra; Laudi, Elisa; Lea, Ramona; Leardini, Lucia; Lee, Graham Richard; Lee, Seongjoo; Lehas, Fatiha; Lemmon, Roy Crawford; Lenti, Vito; Leogrande, Emilia; Leon Monzon, Ildefonso; Leon Vargas, Hermes; Leoncino, Marco; Levai, Peter; Li, Shuang; Li, Xiaomei; Lien, Jorgen Andre; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Ljunggren, Hans Martin; Lodato, Davide Francesco; Lonne, Per-Ivar; Loginov, Vitaly; Loizides, Constantinos; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Luettig, Philipp Johannes; Lunardon, Marcello; Luparello, Grazia; Lutz, Tyler Harrison; Maevskaya, Alla; Mager, Magnus; Mahajan, Sanjay; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Liudmila; Mal'Kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manko, Vladislav; Manso, Franck; Manzari, Vito; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martin, Nicole Alice; Martin Blanco, Javier; Martinengo, Paolo; Martinez Hernandez, Mario Ivan; Martinez-Garcia, Gines; Martinez Pedreira, Miguel; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Mastroserio, Annalisa; Matyja, Adam Tomasz; Mayer, Christoph; Mazer, Joel Anthony; Mazzoni, Alessandra Maria; Mcdonald, Daniel; Meddi, Franco; Melikyan, Yuri; Menchaca-Rocha, Arturo Alejandro; Meninno, Elisa; Mercado-Perez, Jorge; Meres, Michal; Miake, Yasuo; Mieskolainen, Matti Mikael; Mikhaylov, Konstantin; Milano, Leonardo; Milosevic, Jovan; Minervini, Lazzaro Manlio; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Montes Prado, Esther; Moreira De Godoy, Denise Aparecida; Perez Moreno, Luis Alberto; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Munzer, Robert Helmut; Murakami, Hikari; Murray, Sean; Musa, Luciano; Musinsky, Jan; Naik, Bharati; Nair, Rahul; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Naru, Muhammad Umair; Ferreira Natal Da Luz, Pedro Hugo; Nattrass, Christine; Rosado Navarro, Sebastian; Nayak, Kishora; Nayak, Ranjit; Nayak, Tapan Kumar; Nazarenko, Sergey; Nedosekin, Alexander; Nellen, Lukas; Ng, Fabian; Nicassio, Maria; Niculescu, Mihai; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Cabanillas Noris, Juan Carlos; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Ohlson, Alice Elisabeth; Okatan, Ali; Okubo, Tsubasa; Olah, Laszlo; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Orava, Risto; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Ozdemir, Mahmut; Pachmayer, Yvonne Chiara; Pagano, Paola; Paic, Guy; Pal, Susanta Kumar; Pan, Jinjin; Pandey, Ashutosh Kumar; Papikyan, Vardanush; Pappalardo, Giuseppe; Pareek, Pooja; Park, Woojin; Parmar, Sonia; Passfeld, Annika; Paticchio, Vincenzo; Patra, Rajendra Nath; Paul, Biswarup; Pei, Hua; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Peresunko, Dmitry Yurevich; Perez Lara, Carlos Eugenio; Perez Lezama, Edgar; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrov, Viacheslav; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Ozelin De Lima Pimentel, Lais; Pinazza, Ombretta; Pinsky, Lawrence; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Porteboeuf, Sarah Julie; Porter, R Jefferson; Pospisil, Jan; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Punin, Valery; Putschke, Jorn Henning; Qvigstad, Henrik; Rachevski, Alexandre; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Rami, Fouad; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Read, Kenneth Francis; Redlich, Krzysztof; Reed, Rosi Jan; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riabov, Viktor; Ricci, Renato Angelo; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-Lucian; Rocco, Elena; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roeed, Ketil; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Romita, Rosa; Ronchetti, Federico; Ronflette, Lucile; Rosnet, Philippe; Rossi, Andrea; Roukoutakis, Filimon; Roy, Ankhi; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Sadovskiy, Sergey; Safarik, Karel; Sahlmuller, Baldo; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Salzwedel, Jai Samuel Nielsen; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Sarkar, Debojit; Sarma, Pranjal; Scapparone, Eugenio; Scarlassara, Fernando; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schuchmann, Simone; Schukraft, Jurgen; Schulc, Martin; Schuster, Tim Robin; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Rebecca Michelle; Sefcik, Michal; Seger, Janet Elizabeth; Sekiguchi, Yuko; Sekihata, Daiki; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Senyukov, Serhiy; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shahzad, Muhammed Ikram; Shangaraev, Artem; Sharma, Ankita; Sharma, Mona; Sharma, Monika; Sharma, Natasha; Shigaki, Kenta; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, Catherine Micaela; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Soegaard, Carsten; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Derradi De Souza, Rafael; Sozzi, Federica; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Stachel, Johanna; Stan, Ionel; Stankus, Paul; Stefanek, Grzegorz; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Suljic, Miljenko; Sultanov, Rishat; Sumbera, Michal; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Tabassam, Uzma; Takahashi, Jun; Tambave, Ganesh Jagannath; Tanaka, Naoto; Tangaro, Marco-Antonio; Tarhini, Mohamad; Tariq, Mohammad; Tarzila, Madalina-Gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terasaki, Kohei; Terrevoli, Cristina; Teyssier, Boris; Thaeder, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony Robert; Toia, Alberica; Trogolo, Stefano; Trombetta, Giuseppe; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vanat, Tomas; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vechernin, Vladimir; Veen, Annelies Marianne; Veldhoen, Misha; Velure, Arild; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara Limon, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Villatoro Tello, Abraham; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Vislavicius, Vytautas; Viyogi, Yogendra; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Vranic, Danilo; Vrlakova, Janka; Vulpescu, Bogdan; Wagner, Boris; Wagner, Jan; Wang, Hongkai; Wang, Mengliang; Watanabe, Daisuke; Watanabe, Yosuke; Weber, Michael; Weber, Steffen Georg; Weiser, Dennis Franz; Wessels, Johannes Peter; Westerhoff, Uwe; Whitehead, Andile Mothegi; Wiechula, Jens; Wikne, Jon; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yasin, Zafar; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-Kwon; Yoon, Jin Hee; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zardoshti, Nima; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Chunhui, Zhang; Zhang, Zuman; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2016-09-10

    The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity ($-0.5 10$ GeV/$c$), the particle ratios are consistent with those reported for pp and Pb-Pb collisions at the LHC energies. At intermediate $p_{\\rm T}$ the (anti)proton $R_{\\rm pPb}$ shows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification. At high $p_{\\rm T}$ the charged pion, kaon and (anti)proton $R_{\\rm pPb}$ are consistent with unity within statistical and systematic uncertainties.

  7. Measurement and modeling of out-of-field doses from various advanced post-mastectomy radiotherapy techniques

    Science.gov (United States)

    Yoon, Jihyung; Heins, David; Zhao, Xiaodong; Sanders, Mary; Zhang, Rui

    2017-12-01

    More and more advanced radiotherapy techniques have been adopted for post-mastectomy radiotherapies (PMRT). Patient dose reconstruction is challenging for these advanced techniques because they increase the low out-of-field dose area while the accuracy of out-of-field dose calculations by current commercial treatment planning systems (TPSs) is poor. We aim to measure and model the out-of-field radiation doses from various advanced PMRT techniques. PMRT treatment plans for an anthropomorphic phantom were generated, including volumetric modulated arc therapy with standard and flattening-filter-free photon beams, mixed beam therapy, 4-field intensity modulated radiation therapy (IMRT), and tomotherapy. We measured doses in the phantom where the TPS calculated doses were lower than 5% of the prescription dose using thermoluminescent dosimeters (TLD). The TLD measurements were corrected by two additional energy correction factors, namely out-of-beam out-of-field (OBOF) correction factor K OBOF and in-beam out-of-field (IBOF) correction factor K IBOF, which were determined by separate measurements using an ion chamber and TLD. A simple analytical model was developed to predict out-of-field dose as a function of distance from the field edge for each PMRT technique. The root mean square discrepancies between measured and calculated out-of-field doses were within 0.66 cGy Gy-1 for all techniques. The IBOF doses were highly scattered and should be evaluated case by case. One can easily combine the measured out-of-field dose here with the in-field dose calculated by the local TPS to reconstruct organ doses for a specific PMRT patient if the same treatment apparatus and technique were used.

  8. The AFIS experiment: Detecting low energetic antiprotons in a low earth orbit, using an active target detector

    Energy Technology Data Exchange (ETDEWEB)

    Poeschl, Thomas; Gaisbauer, Dominic; Greenwald, Daniel; Hahn, Alexander; Hauptmann, Philipp; Konorov, Igor; Meng, Lingxin; Paul, Stephan [Physics Department E18, Technische Universitaet Muenchen (Germany); Losekamm, Martin [Physics Department E18, Technische Universitaet Muenchen (Germany); Institute of Astronautics, Technische Universitaet Muenchen (Germany); Renker, Dieter [Physics Department E17, Technische Universitaet Muenchen (Germany)

    2014-07-01

    Since the first observation of geomagnetically trapped antiprotons by the PAMELA experiment and the new results on the positron excess by the AMS-02 experiment, the creation and transport of antimatter in the Earth's upper atmosphere attracts more and more attention both at theoretical and experimental side. For this reason the AFIS experiment was initiated to measure the flux of low energetic antiprotons in the South Atlantic Anomaly (SAA). We developed an active target detector made from scintillating fibers connected to silicon photomultipliers which allows to detect antiprotons in the energy interval of about 30 MeV-100 MeV. The stopping curve of incoming antiprotons (Bragg peak) and the signal of outgoing pions created from the annihilation, are used for particle identification as well as triggering. We plan to implement this detector on a 3 unit cubesat satellite in the framework the 'Move2Warp' mission, which is carried out as a student project by the Technische Universitaet Muenchen.

  9. To understand radiotherapy

    International Nuclear Information System (INIS)

    2009-01-01

    Dealing with the use of radiotherapy for adults, this guide indicates when a radiotherapy is suggested, how it acts, how the treatment is chosen, which are the professionals involved. It describes how an external radiotherapy takes place and its various techniques, the different types of side effects (general, specific to the treated zone, late effects). It indicates which organs can be treated by curie-therapy, the different curie-therapy treatment modalities, how a curie-therapy takes place and which are its side effects. It outlines how to better cope with radiotherapy (how to be supported, the important role of relatives, everyday life questions, rights). It indicates and comments the different measures adopted for the safety and quality of radiotherapy

  10. Multilepton production in neutrino interactions and proton-antiproton collisions

    International Nuclear Information System (INIS)

    Valenzuela, G.N.

    1985-01-01

    In part I, we consider the class of events containing 2 or 3 leptons in (anti-neutrino deep inelastic scattering and in proton-antiproton collisions. Understanding the characteristics and rate of production of this type of event has often proven to be a theoretical challenge. We show that a cluster model involving associated-charm production not only accounts for certain dimuon events, but also affords better agreement with experiment regarding trimuons produced in neutrino interactions. We also investigate correlations between D-meson and dimuon production in p anti p collisions in the context of a cluster model which includes the possibility of finding b anti b pairs in jets. Part II consists of a study of radiation zeros in the reaction p anti p → l anti nuγX. It has been proposed that the radiation zero phenomenon could be observed in processes involving the radiative decay of the W-boson. These processes might allow the measurement of the W anomalous magnetic moment. We calculate the effect on this measurement of the decay width and the non-zero transverse momentum of the W. We find that although the radiation zero is filled in to some extent, it might still be possible to estimate the magnetic moment of the W in future experiments

  11. Radiotherapy physics

    International Nuclear Information System (INIS)

    Chen, G.T.Y.; Collier, J.M.; Lyman, J.T.; Pitluck, S.

    1982-01-01

    The Radiotherapy Physics Group works on the physical and biophysical aspects of charged particle radiotherapy. Our activities include the development of isosurvival beams (beams of uniform biological effect), computerized treatment planning development for charged particle radiotherapy, design of compensation to shape dose distributions, and development of dosimetry techniques to verify planned irradiations in both phantoms and patients

  12. IAEA/WHO TLD postal dose audit service and high precision measurements for radiotherapy level dosimetry

    International Nuclear Information System (INIS)

    Izewska, J.; Bera, P.; Vatnitsky, S.

    2002-01-01

    Since 1969 the International Atomic Energy Agency, together with the World Health Organization, has performed postal TLD audits to verify calibration of radiotherapy beams in developing countries. The TLD programme also monitors activities of Secondary Standard Dosimetry Laboratories (SSDLs). The programme has checked approximately 4000 clinical beams in over 1100 hospitals, and in many instances significant errors have been detected in the beam calibration. Subsequent follow-up actions help to resolve the discrepancies, thus preventing further mistreatment of patients. The audits for SSDLs check the implementation of the dosimetry protocol in order to assure proper dissemination of dosimetry standards to the end-users. The TLD audit results for SSDLs show good consistency in the basic dosimetry worldwide. New TLD procedures and equipment have recently been introduced by the IAEA that include a modified TLD calibration methodology and computerised tools for automation of dose calculation from TLD readings. (author)

  13. The Floor's the Limit (Antiproton energies to hit new low)

    CERN Document Server

    2000-01-01

    Celebrating the success of the RFQ in Aarhus. Left to right: Alessanda Lombardi (CERN), Iouri Bylinskii (CERN), Alex Csete (Aarhus), Ulrik Uggerhøj (Aarhus), Ryu Hayano (Tokyo, spokesman ASACUSA), Helge Knudsen (Aarhus), Werner Pirkl (CERN), Ryan Thompson (Aarhus), Søren P. Møller (Aarhus). Although in particle physics we are accustomed to strive for higher and higher energies, this is not always the most interesting thing to do with antiprotons. Indeed, as recent issues of the Bulletin have suggested, the signpost on the road to a closer look at the antiproton points towards ever-lower energies. The CERN Antiproton Decelerator decelerates antipro-tons emerging from a target placed in the path of a 26 GeV/c proton beam from 90 % of to about 10 % of the speed of light. However, even this is far too fast for many of the most interesting experiments on antiprotons planned by Danish and Japanese members of the ASACUSA collaboration. Tokyo University has therefore financed the con...

  14. Atomic Spectroscopy and Collisions Using Slow Antiprotons \\\\ ASACUSA Collaboration

    CERN Multimedia

    Matsuda, Y; Lodi-rizzini, E; Kuroda, N; Schettino, G; Hori, M; Pirkl, W; Mascagna, V; Malbrunot, C L S; Yamazaki, Y; Eades, J; Simon, M; Massiczek, O; Sauerzopf, C; Nagata, Y; Knudsen, H; Uggerhoj, U I; Mc cullough, R W; Toekesi, K M; Venturelli, L; Widmann, E; Zmeskal, J; Kanai, Y; Kristiansen, H; Todoroki, K; Bartel, M A; Moller, S P; Charlton, M; Leali, M; Diermaier, M; Kolbinger, B

    2002-01-01

    ASACUSA (\\underline{A}tomic \\underline{S}pectroscopy \\underline{A}nd \\underline{C}ollisions \\underline{U}sing \\underline{S}low \\underline{A}ntiprotons) is a collaboration between a number of Japanese and European research institutions, with the goal of studying bound and continuum states of antiprotons with simple atoms.\\\\ Three phases of experimentation are planned for ASACUSA. In the first phase, we use the direct $\\overline{p}$ beam from AD at 5.3 MeV and concentrate on the laser and microwave spectroscopy of the metastable antiprotonic helium atom, $\\overline{p}$He$^+$, consisting of an electron and antiproton bound by the Coulomb force to the helium nucleus. Samples of these are readily created by bringing AD antiproton beam bunches to rest in helium gas. With the help of techniques developed at LEAR for resonating high precision laser beams with antiproton transitions in these atoms, ASACUSA achieved several of these first-phase objectives during a few short months of AD operation in 2000. Six atomic tr...

  15. Large amounts of antiproton production by heavy ion collision

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroshi; Powell, J.

    1987-01-01

    To produce large amounts of antiprotons, on the order of several grams/year, use of machines to produce nuclear collisions are studied. These can be of either proton-proton, proton-nucleus and nucleus-nucleus in nature. To achieve high luminosity colliding beams, on the order of 10/sup 41/ m/cm/sup 2/, a self-colliding machine is required, rather than a conventional circular colliding type. The self-colliding machine can produce additional antiprotons through successive collisions of secondary particles, such as spectator nucleons. A key problem is how to collect the produced antiprotons without capture by beam nuclei in the collision zone. Production costs for anti-matter are projected for various energy source options and technology levels. Dedicated facilities using heavy ion collisions could produce antiproton at substantially less than 1 million $/milligram. With co-production of other valuable products, e.g., nuclear fuel for power reactors, antiproton costs could be reduced to even lower values.

  16. Voice quality after endoscopic laser surgery and radiotherapy for early glottic cancer: objective measurements emphasizing the Voice Handicap Index

    Science.gov (United States)

    Caminero Cueva, Maria Jesús; Señaris González, Blanca; Llorente Pendás, José Luis; Gorriz Gil, Carmen; López Llames, Aurora; Alonso Pantiga, Ramón; Suárez Nieto, Carlos

    2007-01-01

    We analyzed the functional outcome and self-evaluation of the voice of patients with T1 glottic carcinoma treated with endoscopic laser surgery and radiotherapy. We performed an objective voice evaluation, as well as a physical, emotional and functional well being assessment of 19 patients treated with laser surgery and 18 patients treated with radiotherapy. Voice quality is affected both by surgery and radiotherapy. Voice parameters only show differences in the maximum phonation time between both treatments. Results in the Voice Handicap Index show that radiotherapy has less effect on patient voice quality perception. There is a reduced impact on the patient’s perception of voice quality after radiotherapy, despite there being no significant differences in vocal quality between radiotherapy and laser cordectomy. PMID:17999074

  17. Experimental and computational study of the injection of antiprotons into a positron plasma for antihydrogen production

    DEFF Research Database (Denmark)

    Amole, C.; Ashkezari, M.D.; Baquero-Ruiz, M.

    2013-01-01

    are commonly produced by mixing antiprotons and positrons stored in a nested Penning-Malmberg trap, which was achieved in ALPHA by an autoresonant excitation of the antiprotons, injecting them into the positron plasma. In this work, a hybrid numerical model is developed to simulate antiproton and positron...

  18. Metastable states in antiprotonic helium atoms an island stability in a sea of continuum

    CERN Document Server

    Korobov, V I

    2002-01-01

    In this contribution we consider a phenomenon of metastable states in antiprotonic helium atoms, precise spectroscopy of these states and a present-day study of the electromagnetic properties of antiprotons. Calculation of nonrelativistic energies, relativistic and QED corrections as well as the fine and hyperfine structure and the magnetic moment of an antiproton are the main parts of this study. Refs. 22 (nevyjel)

  19. A comparison of mean parotid gland dose with measures of parotid gland function after radiotherapy for head-and-neck cancer: Implications for future trials

    International Nuclear Information System (INIS)

    Roesink, Judith M.; Schipper, Maria; Busschers, Wim; Raaijmakers, Cornelis P.J.; Terhaard, Chris H.J.

    2005-01-01

    Purpose: To determine the most adequate parameter to measure the consequences of reducing the parotid gland dose. Methods and Materials: One hundred eight patients treated with radiotherapy for various malignancies of the head and neck were prospectively evaluated using three methods. Parotid gland function was objectively determined by measuring stimulated parotid flow using Lashley cups and scintigraphy. To assess xerostomia-related quality of life, the head-and-neck cancer module European Organization for Research and Treatment of Cancer QLQ (Quality of Life Questionnaire) H and N35 was used. Measurements took place before radiotherapy and 6 weeks and 12 months after the completion of radiotherapy. Complication was defined for each method using cutoff values. The correlation between these complications and the mean parotid gland dose was investigated to find the best measure for parotid gland function. Results: For both flow and scintigraphy data, the best definition for objective parotid gland toxicity seemed to be reduction of stimulated parotid flow to ≤25% of the preradiotherapy flow. Of all the subjective variables, only the single item dry mouth 6 weeks after radiotherapy was found to be significant. The best correlation with the mean parotid gland dose was found for the stimulated flow measurements. The predictive ability was the highest for the time point 1 year after radiotherapy. Subjective findings did not correlate with the mean parotid dose. Conclusions: Stimulated flow measurements using Lashley cups, with a complication defined as flow ≤25% of the preradiotherapy output, correlated best with the mean parotid gland dose. When reduction of the mean dose to the parotid gland is intended, the stimulated flow measurement is the best method for evaluating parotid gland function

  20. Loss of lung function after chemo-radiotherapy for NSCLC measured by perfusion SPECT/CT: Correlation with radiation dose and clinical morbidity

    DEFF Research Database (Denmark)

    Farr, Katherina P; Møller, Ditte S; Khalil, Azza A

    2015-01-01

    BACKGROUND: The purpose of the study was to assess dose and time dependence of radiotherapy (RT)-induced changes in regional lung function measured with single photon emission computed tomography (SPECT) of the lung and relate these changes to the symptomatic endpoint of radiation pneumonitis (RP...

  1. A comparison of mean parotid gland dose with measures of parotid gland function after radiotherapy for head-and-neck cancer : Implications for future trials

    NARCIS (Netherlands)

    Roesink, JM; Schipper, M; Busschers, W; Raaijmakers, CPJ; Terhaard, CHJ

    2005-01-01

    Purpose: To determine the most adequate parameter to measure the consequences of reducing the parotid gland dose. Methods and Materials: One hundred eight patients treated with radiotherapy for various malignancies of the head and neck were prospectively evaluated using three methods. Parotid gland

  2. Formation of charmonium states in antiproton-proton annihilation

    International Nuclear Information System (INIS)

    Cester, R.

    1984-01-01

    Experiment R704 at the CERN ISR studies charmonium states formed directly in antiproton-proton annihilations. A high luminosity and good centre of mass energy definition are obtained by intersecting a low-energy antiproton beam circulating in ring II at the ISR, with a molecular H 2 jet target. During two test runs, for an integrated luminosity of 265 nb -1 , we have observed formation of psi and chi 2 . Taking the known psi mass as reference, we have checked that the nominal ISR momentum is correct and reproducible to 2.0 MeV/c

  3. Antiprotons from spallation of cosmic rays on ISM

    CERN Document Server

    Donato, F

    2002-01-01

    We provide the first evaluation of the secondary interstellar cosmic antiproton flux that is fully consistent with cosmic ray nuclei in the framework of a two-zone diffusion model. We also study and conservatively quantify all possible sources of uncertainty that may affect that antiproton flux. Uncertainties related to propagation are shown to range between 10% and 25%, depending on which part of the spectrum is considered, while the ones related to nuclear physics stand around 22-25 % over all the energy spectrum.

  4. Relativistic hydrodynamics, heavy ion reactions and antiproton annihilation

    International Nuclear Information System (INIS)

    Strottman, D.

    1985-01-01

    The application of relativistic hydrodynamics to relativistic heavy ions and antiproton annihilation is summarized. Conditions for validity of hydrodynamics are presented. Theoretical results for inclusive particle spectra, pion production and flow analysis are given for medium energy heavy ions. The two-fluid model is introduced and results presented for reactions from 800 MeV per nucleon to 15 GeV on 15 GeV per nucleon. Temperatures and densities attained in antiproton annihilation are given. Finally, signals which might indicate the presence of a quark-gluon plasma are briefly surveyed

  5. Transverse instability of the antiproton beam in the Recycler Ring

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Bhat, C.M.; Burov, A.; Crisp, J.; Eddy, N.; Hu, M.; Shemyakin, A.; /Fermilab

    2011-03-01

    The brightness of the antiproton beam in Fermilab's 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

  6. Low energy antiprotons from supernova exploding in dense clouds

    Science.gov (United States)

    Stephens, S. A.; Mauger, B. G.

    1984-01-01

    The antiproton spectrum resulting from a supernova, which exploded inside a dense cloud, is calculated by taking into account all energy loss processes including adiabatic deceleration during the expansion phase. The influence of various energy loss processes on the evolution of the spectrum as the supernova expands is investigated. It is shown that if about 25 percent of the cosmic ray nucleons are from such sources, the observed low energy antiprotons can be explained, provided the effect of solar modulation is not very large. The possibility of obtaining enhanced low energy spectrum by this process is also examined.

  7. A volumetric approach to path-length measurements is essential when treating radiotherapy with modulated beams

    Energy Technology Data Exchange (ETDEWEB)

    Forde, Elizabeth, E-mail: eforde@tcd.ie [Discipline of Radiation Therapy, School of Medicine, Trinity College Dublin, Dublin (Ireland); Booth, Jeremy [Northern Sydney Cancer Centre, Royal North Shore Hospital, New South Wales (Australia); Leech, Michelle [Discipline of Radiation Therapy, School of Medicine, Trinity College Dublin, Dublin (Ireland)

    2014-07-01

    The established dosimetric benefits of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy have lead to their increased use in prostate radiotherapy. Complimenting these techniques, volumetric image guidance has supported increased positional accuracy. In addition, 3-dimensional image guidance has also allowed for assessment of potential dosimetric variation that can be attributed to a deformation of either internal or external structures, such as rectal distension or body contour. Compounding these issues is the variation of tissue density through which the new field position passes and also the variation of dose across a modulated beam. Despite the growing level of interest in this area, there are only a limited number of articles that examine the effect of a variation in beam path length, particularly across a modulated field. IMRT and volumetric-modulated radiation therapy (VMAT) fields are dynamic in nature, and the dose gradient within these fields is variable. Assessment of variation of path length away from the beam's central axis and across the entire field is vital where there is considerable variation of dose within the field, such as IMRT and VMAT. In these cases, reliance on the traditional central axis to focus skin distances is no longer appropriate. This article discusses these more subtle challenges that may have a significant clinical effect if left unrecognized and undervalued.

  8. A volumetric approach to path-length measurements is essential when treating radiotherapy with modulated beams.

    Science.gov (United States)

    Forde, Elizabeth; Booth, Jeremy; Leech, Michelle

    2014-01-01

    The established dosimetric benefits of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy have lead to their increased use in prostate radiotherapy. Complimenting these techniques, volumetric image guidance has supported increased positional accuracy. In addition, 3-dimensional image guidance has also allowed for assessment of potential dosimetric variation that can be attributed to a deformation of either internal or external structures, such as rectal distension or body contour. Compounding these issues is the variation of tissue density through which the new field position passes and also the variation of dose across a modulated beam. Despite the growing level of interest in this area, there are only a limited number of articles that examine the effect of a variation in beam path length, particularly across a modulated field. IMRT and volumetric-modulated radiation therapy (VMAT) fields are dynamic in nature, and the dose gradient within these fields is variable. Assessment of variation of path length away from the beam׳s central axis and across the entire field is vital where there is considerable variation of dose within the field, such as IMRT and VMAT. In these cases, reliance on the traditional central axis to focus skin distances is no longer appropriate. This article discusses these more subtle challenges that may have a significant clinical effect if left unrecognized and undervalued. Copyright © 2014 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  9. Measurements of the top quark pair production cross section in lepton+jets final states using a topological multivariate technique as well as lifetime b-tagging in proton-antiproton collisions at {radical}(s)=1.96 TeV with the DOe detector at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Golling, T.

    2005-01-01

    Two alternative measurements of the tt production cross section at {radical}(s)=1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The tt production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X} = 5.13{sub -1.57}{sup +1.76} (stat) {sub -1.10}{sup +0.96} (syst) {+-}0.33 (lumi) pb in the muon+jets channel, using 229.1 pb{sup -1}, and in the combination with the electron+jets channel (226.3 pb{sup -1}) {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t}+X = 6.60{sub -1.28}{sup +1.37} (stat) {sub -1.11}{sup +1.25} (syst) {+-} 0.43 (lumi) pb. The second measurement presented reconstructs explicitly secondary vertices to do lifetime b-tagging. The measurement combines the muon+jets and the electron+jets channel, using 158.4 pb{sup -1} and 168.8 pb{sup -1}, respectively: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X} = 8.24{sub -1.25}{sup +1.34} (stat) {sub -1.63}{sup +1.89} (syst) {+-} 0.54 (lumi) pb. (orig.)

  10. High-precision comparison of the antiproton-to-proton charge-to-mass ratio.

    Science.gov (United States)

    Ulmer, S; Smorra, C; Mooser, A; Franke, K; Nagahama, H; Schneider, G; Higuchi, T; Van Gorp, S; Blaum, K; Matsuda, Y; Quint, W; Walz, J; Yamazaki, Y

    2015-08-13

    Invariance under the charge, parity, time-reversal (CPT) transformation is one of the fundamental symmetries of the standard model of particle physics. This CPT invariance implies that the fundamental properties of antiparticles and their matter-conjugates are identical, apart from signs. There is a deep link between CPT invariance and Lorentz symmetry--that is, the laws of nature seem to be invariant under the symmetry transformation of spacetime--although it is model dependent. A number of high-precision CPT and Lorentz invariance tests--using a co-magnetometer, a torsion pendulum and a maser, among others--have been performed, but only a few direct high-precision CPT tests that compare the fundamental properties of matter and antimatter are available. Here we report high-precision cyclotron frequency comparisons of a single antiproton and a negatively charged hydrogen ion (H(-)) carried out in a Penning trap system. From 13,000 frequency measurements we compare the charge-to-mass ratio for the antiproton (q/m)p- to that for the proton (q/m)p and obtain (q/m)p-/(q/m)p − 1 =1(69) × 10(-12). The measurements were performed at cyclotron frequencies of 29.6 megahertz, so our result shows that the CPT theorem holds at the atto-electronvolt scale. Our precision of 69 parts per trillion exceeds the energy resolution of previous antiproton-to-proton mass comparisons as well as the respective figure of merit of the standard model extension by a factor of four. In addition, we give a limit on sidereal variations in the measured ratio of baryonic antimatter, and it sets a new limit on the gravitational anomaly parameter of |α − 1| < 8.7 × 10(-7).

  11. The BESS Search for Cosmic-Ray Antiproton Origins and for Cosmological Antimatter

    Science.gov (United States)

    Mitchell, John; Yamamoto, Akira

    2009-01-01

    The apex of the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) program was reached with the Antarctic flight of BESS-Polar II, during the 2007-2008 Austral Summer, that obtained 24.5 days of data on over 4.7 billion cosmic-ray events. The US-Japan BESS Collaboration uses elementary particle measurements to study the early Universe and provides fundamental data on the spectra of light cosmic-ray elements and isotopes. BESS measures the energy spectra of cosmic-ray antiprotons to investigate signatures of possible exotic sources, such as dark-matter candidates, and searches for heavier antinuclei that might reach Earth from antimatter domains formed during symmetry breaking processes in the early Universe. Since 1993, BESS has carried out eleven high-latitude balloon flights, two of long duration, that together have defined the study of antiprotons below about 4 GeV, provided standard references for light element and isotope spectra, and set the most sensitive limits on the existence of antideuterons and antihelium. The BESS-Polar II flight took place at Solar Minimum, when the sensitivity of the low-energy antiproton measurements to a primary source is greatest. The rich BESS-Polar II dataset more than doubles the combined data from all earlier BESS flights and has 10-20 times the statistics of BESS data from the previous Solar Minimum. Here, we summarize the scientific results of BESS program, focusing on the results obtained using data from the long-duration flights of BESS-Polar I (2004) and BESS-Polar II.

  12. Voice Range Profile and Health-related Quality of Life Measurements Following Voice Rehabilitation After Radiotherapy; a Randomized Controlled Study.

    Science.gov (United States)

    Tuomi, Lisa; Johansson, Mia; Lindell, Ellen; Folkestad, Lena; Malmerfors, Maria; Finizia, Caterina

    2017-01-01

    The aim of the present study was to investigate the effects of voice rehabilitation in patients treated with radiotherapy for laryngeal cancer. A total of 42 patients with laryngeal cancer who are treated with radiotherapy with curative intent participated in a randomized controlled study. The collected data were voice range profiles (VPRs) and patient-reported outcome (PRO) instruments for measurement of self-perceived communication function (Swedish Self-Evaluation for Communication Experiences after Laryngeal cancer (S-SECEL)) and health related quality of life (HRQL) (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30/Head and Neck module). Data were collected 1 month (pre voice rehabilitation), 6 months, and 12 months postradiotherapy. Of the patients, 19 received voice rehabilitation, whereas 23 constituted a control group. There were several statistically significant improvements in the study group concerning the HRQL and self-perceived communication function. The largest improvements occurred between occasions 1 (prevoice rehabilitation) and 2 (6-month postradiotherapy) and then remained constant. VRP area demonstrated a statistically significant difference when comparing changes over time, where the study group improved more than the control group. HRQL and self-perceived communication function showed improvement in the study group and trends of impairment in the control group. This result might suggest that it would be beneficial for the patients as well as in a health economic perspecitve, to receive voice rehabilitatiom to make a faster improvement of the HRQL and self-perceived communication function. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  13. Evaluation of motion measurement using cine MRI for image guided stereotactic body radiotherapy on a new phantom platform

    Science.gov (United States)

    Cai, Jing; Wang, Ziheng; Yin, Fang-Fang

    2011-01-01

    The objective of this study is to investigate accuracy of motion tracking of cine magnetic resonance imaging (MRI) for image-guided stereotactic body radiotherapy. A phantom platform was developed in this work to fulfill the goal. The motion phantom consisted of a platform, a solid thread, a motor and a control system that can simulate motion in various modes. To validate its reproducibility, the phantom platform was setup three times and imaged with fluoroscopy using an electronic portal imaging device (EPID) for the same motion profile. After the validation test, the phantom platform was evaluated using cine MRI at 2.5 frames/second on a 1.5T GE scanner using five different artificial profiles and five patient profiles. The above profiles were again measured with EPID fluoroscopy and used as references. Discrepancies between measured profiles from cine MRI and EPID were quantified using root-mean-square (RMS) and standard deviation (SD). Pearson’s product moment correlational analysis was used to test correlation. The standard deviation for the reproducibility test was 0.28 mm. The discrepancies (RMS) between all profiles measured by cine MRI and EPID fluoroscopy ranged from 0.30 to 0.49 mm for artificial profiles and ranged from 0.75 to 0.91 mm for five patient profiles. The cine MRI sequence could precisely track phantom motion and the proposed motion phantom was feasible to evaluate cine MRI accuracy. PMID:29296304

  14. Measurement and modeling of the dose distribution in homogenous medium for a proton beam devoted to radiotherapy

    International Nuclear Information System (INIS)

    Oozeer, R.

    1996-12-01

    A theoretical and experimental study of the dose distribution in the proton beams of the proton therapy center at Orsay has been investigated. The theoretical study highlighted the prominent interactions of protons used for radiotherapy with the biological media, are the energy loss by inelastic collisions with electrons, and the multiple coulomb diffusions with nuclei. Experimental measurements have been realised with a small size diode in homogenous and heterogenous medium. The measurements in a water phantom lead to the finalizing of a lateral penumbra model for the intra skull beam. The measurements in heterogenous medium highlighted the importance of the fine structure of heterogeneities on the yield in depth curve shape. Concerning the simple fine structure heterogeneities, we defined the notions of equivalence to water for the heterogeneities, specific to protons, concerning the yields in depth and the diffusion. Moreover, a calculation of dose distribution, for a mono energy beam in a phantom of simple geometry, using the mini beam technique and the Highland formalism was implemented. This approach is compatible with a definition of heterogeneities as macroscopic structure. Concerning the heterogeneities of fine structure (equally complex), an analysis of the degradation of yield in depth curves was lead, indicating that it was possible to to take them into account from the scanner images. A such approach implies calculation models using directly the electronic density relative to water of each of voxel intercepted by the radiation. (N.C.)

  15. Physics Performance Report for PANDA : Strong Interaction Studies with Antiprotons

    NARCIS (Netherlands)

    Erni, W.; Keshelashvili, I.; Krusche, B.; Steinacher, M.; Heng, Y.; Liu, Z.; Liu, H.; Shen, X.; Wang, O.; Xu, H.; Becker, J.; Feldbauer, F.; Heinsius, F. -H.; Held, T.; Koch, H.; Kopf, B.; Pelizaeus, M.; Schroeder, T.; Steinke, M.; Wiedner, U.; Zhong, J.; Bianconi, A.; Bragadireanu, M.; Pantea, D.; Tudorache, A.; Tudorache, V.; De Napoli, M.; Giacoppo, F.; Raciti, G.; Rapisarda, E.; Sfienti, C.; Bialkowski, E.; Budzanowski, A.; Czech, B.; Kistryn, M.; Kliczewski, S.; Kozela, A.; Kulessa, P.; Pysz, K.; Schaefer, W.; Siudak, R.; Szczurek, A.; Czy. zycki, W.; Domagala, M.; Hawryluk, M.; Lisowski, E.; Lisowski, F.; Wojnar, L.; Gil, D.; Hawranek, P.; Kamys, B.; Kistryn, St.; Korcyl, K.; Krzemien, W.; Magiera, A.; Moskal, P.; Rudy, Z.; Salabura, P.; Smyrski, J.; Wronska, A.; Al-Turany, M.; Augustin, I.; Deppe, H.; Flemming, H.; Gerl, J.; Goetzen, K.; Hohler, R.; Lehmann, D.; Lewandowski, B.; Luehning, J.; Maas, F.; Mishra, D.; Orth, H.; Peters, K.; Saito, T.; Schepers, G.; Schmidt, C. J.; Schmitt, L.; Schwarz, C.; Voss, B.; Wieczorek, P.; Wilms, A.; Brinkmann, K. -T.; Freiesleben, H.; Jaekel, R.; Kliemt, R.; Wuerschig, T.; Zaunick, H. -G.; Abazov, V. M.; Alexeev, G.; Arefiev, A.; Astakhov, V. I.; Barabanov, M. Yu.; Batyunya, B. V.; Davydov, Yu. I.; Dodokhov, V. Kh.; Efremov, A. A.; Fedunov, A. G.; Feshchenko, A. A.; Galoyan, A. S.; Grigoryan, S.; Karmokov, A.; Koshurnikov, E. K.; Kudaev, V. Ch.; Lobanov, V. I.; Lobanov, Yu. Yu.; Makarov, A. F.; Malinina, L. V.; Malyshev, V. L.; Mustafaev, G. A.; Olshevski, A.; . Pasyuk, M. A.; Perevalova, E. A.; Piskun, A. A.; Pocheptsov, T. A.; Pontecorvo, G.; Rodionov, V. K.; Rogov, Yu. N.; Salmin, R. A.; Samartsev, A. G.; Sapozhnikov, M. G.; Shabratova, A.; Shabratova, G. S.; Skachkova, A. N.; Skachkov, N. B.; Strokovsky, E. A.; Suleimanov, M. K.; Teshev, R. Sh.; Tokmenin, V. V.; Uzhinsky, V. V.; Vodopianov, A. S.; Zaporozhets, S. A.; Zhuravlev, N. I.; Zorin, A. G.; Branford, D.; Foehl, K.; Glazier, D.; Watts, D.; Woods, P.; Eyrich, W.; Lehmann, A.; Teufel, A.; Dobbs, S.; Metreveli, Z.; Seth, K.; Tann, B.; Tomaradze, A.; Bettoni, D.; Carassiti, V.; Cecchi, A.; Dalpiaz, P.; Fioravanti, E.; Garzia, I.; Negrini, M.; Savri`e, M.; Stancari, G.; Dulach, B.; Gianotti, P.; Guaraldo, C.; Lucherini, V.; Pace, E.; Bersani, A.; Macri, M.; Marinelli, M.; Parodi, R. F.; Brodski, I.; Doering, W.; Drexler, P.; Dueren, M.; Gagyi-Palffy, Z.; Hayrapetyan, A.; Kotulla, M.; Kuehn, W.; Lange, S.; Liu, M.; Metag, V.; Nanova, M.; Novotny, R.; Salz, C.; Schneider, J.; Schoenmeier, P.; Schubert, R.; Spataro, S.; Stenzel, H.; Strackbein, C.; Thiel, M.; Thoering, U.; Yang, S.; Clarkson, T.; Cowie, E.; Downie, E.; Hill, G.; Hoek, M.; Ireland, D.; Kaiser, R.; Keri, T.; Lehmann, I.; Livingston, K.; Lumsden, S.; MacGregor, D.; McKinnon, B.; Murray, M.; Protopopescu, D.; Rosner, G.; Seitz, B.; Yang, G.; Babai, M.; Biegun, A. K.; Bubak, A.; Guliyev, E.; Suyam Jothi, Vanniarajan; Kavatsyuk, M.; Loehner, H.; Messchendorp, J.; Smit, H.; van der Weele, J. C.; Garcia, F.; Riska, D. -O.; Buescher, M.; Dosdall, R.; Dzhygadlo, R.; Gillitzer, A.; Grunwald, D.; Jha, V.; Kemmerling, G.; Kleines, H.; Lehrach, A.; Maier, R.; Mertens, M.; Ohm, H.; Prasuhn, D.; Randriamalala, T.; Ritman, J.; Roeder, M.; Stockmanns, T.; Wintz, P.; Wuestner, P.; Kisiel, J.; Li, S.; Li, Z.; Sun, Z.; Xu, H.; Fissum, S.; Hansen, K.; Isaksson, L.; Lundin, M.; Schroeder, B.; Achenbach, P.; Mora Espi, M. C.; Pochodzalla, J.; Sanchez, S.; Sanchez-Lorente, A.; Dormenev, V. I.; Fedorov, A. A.; Korzhik, M. V.; Missevitch, O. V.; Balanutsa, V.; Chernetsky, V.; Demekhin, A.; Dolgolenko, A.; Fedorets, P.; Gerasimov, A.; Goryachev, V.; Boukharov, A.; Malyshev, O.; Marishev, I.; Semenov, A.; Hoeppner, C.; Ketzer, B.; Konorov, I.; Mann, A.; Neubert, S.; Paul, S.; Weitzel, Q.; Khoukaz, A.; Rausmann, T.; Taeschner, A.; Wessels, J.; Varma, R.; Baldin, E.; Kotov, K.; Peleganchuk, S.; Tikhonov, Yu.; Boucher, J.; Hennino, T.; Kunne, R.; Ong, S.; Pouthas, J.; Ramstein, B.; Rosier, P.; Sudol, M.; Van de Wiele, J.; Zerguerras, T.; Dmowski, K.; Korzeniewski, R.; Przemyslaw, D.; Slowinski, B.; Boca, G.; Braghieri, A.; Costanza, S.; Fontana, A.; Genova, P.; Lavezzi, L.; Montagna, P.; Rotondi, A.; Belikov, N. I.; Davidenko, A. M.; Derevschikov, A. A.; Goncharenko, Y. M.; Grishin, V. N.; Kachanov, V. A.; Konstantinov, D. A.; Kormilitsin, V. A.; Kravtsov, V. I.; Matulenko, Y. A.; Melnik, Y. M.; Meschanin, A. P.; Minaev, N. G.; Mochalov, V. V.; Morozov, D. A.; Nogach, L. V.; Nurushev, S. B.; Ryazantsev, A. V.; Semenov, P. A.; Soloviev, L. F.; Uzunian, A. V.; Vasiliev, A. N.; Yakutin, A. E.; Baeck, T.; Cederwall, B.; Bargholtz, C.; Geren, L.; Tegner, P. E.; Belostotski, S.; Gavrilov, G.; Itzotov, A.; Kisselev, A.; Kravchenko, P.; Manaenkov, S.; Miklukho, O.; Naryshkin, Y.; Veretennikov, D.; Vikhrov, V.; Zhadanov, A.; Fava, L.; Panzieri, D.; Alberto, D.; Amoroso, A.; Botta, E.; Bressani, T.; Bufalino, S.; Bussa, M. P.; Busso, L.; De Mori, F.; Destefanis, M.; Ferrero, L.; Grasso, A.; Greco, M.; Kugathasan, T.; Maggiora, M.; Marcello, S.; Serbanut, G.; Sosio, S.; Bertini, R.; Calvo, D.; Coli, S.; De Remigis, P.; Feliciello, A.; Filippi, A.; Giraudo, G.; Mazza, G.; Rivetti, A.; Szymanska, K.; Tosello, F.; Wheadon, R.; Morra, O.; Agnello, M.; Iazzi, F.; Szymanska, K.; Birsa, R.; Bradamante, F.; Bressan, A.; Martin, A.; Clement, H.; Ekstroem, C.; Calen, H.; Grape, S.; Hoeistad, B.; Johansson, T.; Kupsc, A.; Marciniewski, P.; Thome, E.; Zlomanczuk, J.; Diaz, J.; Ortiz, A.; Borsuk, S.; Chlopik, A.; Guzik, Z.; Kopec, J.; Kozlowski, T.; Melnychuk, D.; Plominski, M.; Szewinski, J.; Traczyk, K.; Zwieglinski, B.; Buehler, P.; Gruber, A.; Kienle, P.; Marton, J.; Widmann, E.; Zmeskal, J.; Lutz, M. F. M.; Pire, B.; Scholten, O.; Timmermans, R.

    To study fundamental questions of hadron and nuclear physics in interactions of antiprotons with nucleons and nuclei, the universal PANDA detector will be built. Gluonic excitations, the physics of strange and charm quarks and nucleon structure studies will be performed with unprecedented accuracy

  16. Annihilation of antiprotons stopped in liquid hydrogen and deuterium

    International Nuclear Information System (INIS)

    Dalkarov, O.D.; Kerbikov, B.O.; Markushin, V.E.

    1976-01-01

    Detailed analysis is given of stopping antiproton annihilation in liquid hydrogen and deuterium. Connection between capture schedule and properties of bound states in nucleon-antinucleon system is established. The theoretical predictions are compared with experimental data which appeared in 1971-75

  17. Relative Biological Effectiveness and Peripheral Damage of Antiproton Annihilation

    CERN Multimedia

    Kavanagh, J N; Kaiser, F; Tegami, S; Schettino, G; Kovacevic, S; Hajdukovic, D; Knudsen, H; Currell, F J; Toelli, H T; Doser, M; Holzscheiter, M; Herrmann, R; Timson, D J; Alsner, J; Landua, R; Comor, J; Moller, S P; Beyer, G

    2002-01-01

    The use of ions to deliver radiation to a body for therapeutic purposes has the potential to be significant improvement over the use of low linear energy transfer (LET) radiation because of the improved energy deposition profile and the enhanced biological effects of ions relative to photons. Proton therapy centers exist and are being used to treat patients. In addition, the initial use of heavy ions such as carbon is promising to the point that new treatment facilities are planned. Just as with protons or heavy ions, antiprotons can be used to deliver radiation to the body in a controlled way; however antiprotons will exhibit additional energy deposition due to annihilation of the antiprotons within the body. The slowing down of antiprotons in matter is similar to that of protons except at the very end of the range beyond the Bragg peak. Gray and Kalogeropoulos estimated the additional energy deposited by heavy nuclear fragments within a few millimeters of the annihilation vertex to be approximately 30 MeV (...

  18. Development and evaluation of an instrument to measure health-related quality of life in Cuban breast cancer patients receiving radiotherapy.

    Science.gov (United States)

    Lugo, Josefina; Nápoles, Misleidy; Pérez, Inés; Ordaz, Niurka; Luzardo, Mario; Fernández, Leticia

    2014-01-01

    INTRODUCTION Although modern technology has extended the survival of breast cancer patients, treatment's adverse effects impact their health-related quality of life. Currently, no instrument exists capable of identifying the range of problems affecting breast cancer patients receiving radiotherapy in Cuba's socioeconomic and cultural context. OBJECTIVES Construct and validate an instrument to measure the effects of breast cancer and radiotherapy on health-related quality of life in Cuban patients. METHODS The study was conducted at the Oncology and Radiobiology Institute, Havana, Cuba, from January 2010 through December 2011. Inclusion criteria were: adult female, histological diagnosis of breast cancer, treated with ambulatory radiotherapy, and written informed consent; patients unable to communicate orally or in writing, or who had neurologic or psychiatric conditions were excluded. Development phase: focus groups guided by a list of questions were carried out with 50 women. The patients reported 61 problems affecting their health-related quality-of-life. A nominal group (six oncologists and two nurses) identified the same problems. A syntactic analysis of the information was performed to create items for study and measurement scales. Content validity was determined by a nominal group of seven experts using professional judgment. Another 20 patients were selected to evaluate face validity. Validation phase: the instrument was applied to 230 patients at three different points: before radiotherapy, at the end of radiotherapy and four weeks after radiotherapy was concluded. Reliability, construct validity, discriminant validity, predictive validity, interpretability and response burden were evaluated. RESULTS The final instrument developed had 33 items distributed in 4 domains: physical functioning, psychological functioning, social and family relationships, and physical and emotional adverse effects of disease and treatment. There were two discrete items: perceived

  19. Comparison of measured and calculated contralateral breast doses in whole breast radiotherapy for VMAT and standard tangent techniques

    International Nuclear Information System (INIS)

    Tse, T.L.J; Bromley, R.; Booth, J.; Gray, A.

    2011-01-01

    Full text: Objective This study aims to evaluate the accuracy of calculated dose with the Eclipse analytical anisotropic algorithm (AAA) for contralateral breast (CB) in left-sided breast radiotherapy for dual-arc VMA T and standard wedged tangent (SWT) techniques. Methods and materials Internal and surface CB doses were measured with EBT2 film in an anthropomorphic phantom mounted with C-cup and D-cup breasts. The measured point dose was approximated by averaging doses over the 4 x 4 mm 2 central region of each 2 x 2 cm2 piece of film. The dose in the target region of the breast was also measured. The measured results were compared to AAA calculations with calculation grids of I, 2.5 and 5 mm. Results In SWT plans, the average ratios of calculation to measurement for internal doses were 0.63 ± 0.081 and 0.5 I ± 0.28 in the medial and lateral aspects, respectively. Corresponding ratios for surface doses were 0.88 ± 0.22 and 0.38 ± 0.38. In VMAT plans, however, the calculation accuracies showed little dependence on the measurement locations, the ratios were 0.78 ± O. I I and 0.81 ± 0.085 for internal and surface doses. In general, finer calculation resolutions did not inevitably improve the dose estimates of internal doses. For surface doses, using smaller grid size I mm could improve the calculation accuracies on the medial but not the lateral aspects of CB. Conclusion In all plans, AAA had a tendency to underestimate both internal and surface CB doses. Overall, it produces more accurate results in VMAT than SWT plans.

  20. Radiation dose measurements during kilovoltage-cone beam computed tomography imaging in radiotherapy

    Directory of Open Access Journals (Sweden)

    A Sathish Kumar

    2016-01-01

    Conclusion: Radiation dose to the eye, breast, and the surface of the pelvis have been arrived at during CBCT. The doses measured on patients agreed closely with those measured on humanoid phantom and with published values.

  1. What Does The PAMELA Antiproton Spectrum Tell Us About Dark Matter?

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, Dan [Chicago U., Astron. Astrophys. Ctr.; Linden, Tim [Chicago U., KICP; Mertsch, Philipp [KIPAC, Menlo Park

    2015-03-11

    Measurements of the cosmic ray antiproton spectrum can be used to search for contributions from annihilating dark matter and to constrain the dark matter annihilation cross section. Depending on the assumptions made regarding cosmic ray propagation in the Galaxy, such constraints can be quite stringent. We revisit this topic, utilizing a set of propagation models fit to the cosmic ray boron, carbon, oxygen and beryllium data. We derive upper limits on the dark matter annihilation cross section and find that when the cosmic ray propagation parameters are treated as nuisance parameters (as we argue is appropriate), the resulting limits are significantly less stringent than have been previously reported. We also note (as have several previous groups) that simple GALPROP-like diffusion-reacceleration models predict a spectrum of cosmic ray antiprotons that is in good agreement with PAMELA's observations above ~ 5 GeV, but that significantly underpredict the flux at lower energies. Although the complexity of modeling cosmic ray propagation at GeV-scale energies makes it difficult to determine the origin of this discrepancy, we consider the possibility that the excess antiprotons are the result of annihilating dark matter. Suggestively, we find that this excess is best fit for mDM ~ 35 GeV and σ v ~ 10$-$26 cm3/s (to $b\\bar{_b}$), in good agreement with the mass and cross section previously shown to be required to generate the gamma-ray excess observed from the Galactic Center.

  2. Set-up variation of patients treated with radiotherapy to the prostate measured with an electronic portal imaging device

    International Nuclear Information System (INIS)

    Greer, P.B.; Jose, C.C.; Matthews, J.H.L.

    1998-01-01

    The set-up variation of 11 patients treated supine with radical radiotherapy for carcinoma of the prostate was measured with an electronic portal imaging device to determine the adequacy of set-up techniques and current margins, as well as the need for immobilization. During the treatments 172 images of the anterior fields and 159 images of the left-lateral fields were taken and the errors in treatment placement were measured by template matching. The variation in the superior-inferior direction was small, 1.4-1.6 mm (1 SD), while the medio-lateral variation was 2.8 mm (1 SD). The anterior-posterior variation was largest, 4.6 mm (1 SD) with an offset of 3.3 mm anterior. This anterior offset and large anterior-posterior variation suggests that set-up techniques were not optimal for this direction. The 1 cm margin used was adequate for set-up variation except in a small number of cases, which was mainly due to the anterior trend. Random (treatment-to-treatment) variations were small (1.1-2.3 mm; 1 SD), indicating that immobilization would result in only modest improvement in reproducibility for these supine patients. Copyright (1998) Blackwell Science Pty Ltd

  3. Neutrons produced by 1.22 GeV antiproton interactions with nuclei

    CERN Document Server

    Von Egidy, T; Galin, J; Goldenbaum, F; Golubeva, Y S; Hasinoff, M D; Hilscher, D; Iljinov, A S; Jahnke, U; Krause, M; Kurcewicz, W; Ledoux, X; Lott, B; Maier, L; Manrique de Lara, M; Pausch, G; Pienkowski, L; Quednau, B; Schott, W; Schröder, W U; Töke, J

    2000-01-01

    Inclusive neutron energy spectra were measured by time of flight using 1.22 GeV antiprotons from LEAR, CERN, as projectiles and targets from natural Al, Cu, Ag, Ho, Ta, Au, Pb, Bi, and U. The sum of two Maxwellian distributions was fitted to the spectra d/sup 2/ sigma /(d Omega dE) obtained at several forward and backward angles yielding neutron multiplicities M/sub i/ and slope or temperature parameters T/sub i/ for the low-energy (evaporative, i=1) and high- energy (pre-equilibrium, i=2) parts, respectively. M/sub 1/ increases with A, proportional to the nuclear volume, and M/sub 2/ is growing with A/sup 1/3/, proportional to the nuclear radius. The T parameters are nearly independent of A. The results are compared with previous multiplicity measurements with a 4 pi neutron detector, intranuclear cascade calculations and neutron spectra from stopped antiproton annihilation on nuclei. With the measured proton spectra also the ratio of emitted neutrons to protons was determined for Au. (26 refs) .

  4. Evaluation of the contribution of contamination of radiotherapy room surfaces in the measure of exposure rate of radioiodine therapy patients

    International Nuclear Information System (INIS)

    Campos, Rafael Ferreira

    2015-01-01

    The contamination of radiotherapy room surfaces is significant and the measures of patient exposure rate are held on the fourth dependencies, relevant questions are raised: the background radiation of the room stay high due to surface contamination, may interfere with the rate of patient exposure at the time of its release? The monitoring site is important to determine whether the patient will be released? The value of the deal activity and the clinical condition of the patient may increase the contamination, influencing the monitoring results? This paper aims to conduct a quantitative analysis of surface contamination of the contribution of therapeutic room at the time is monitored exposure rate from inpatient. Measurements were made regarding the hospitalization of 32 patients with different doses administered activity, age and of both genders. The measurements were performed in the therapeutic rooms at the hospital Brotherhood Santa Casa de Misericordia de Sao Paulo. Exposure rate measurements were performed at the center of the room at 1 meter of the patient on the day of its release. After his release and prior to decontamination, measurements were performed at predetermined landmarks within the therapeutic room. The results revealed that on average background radiation, high due to surface contamination contributes only 2% of the patient dose rate. It can be considered that even with influence of contamination of surfaces, this is insignificant to determine if the patient may or may not be released. This study suggests that the site in which monitoring occurs exposure rate of the patient should not be decisive for liberation thereof. (author)

  5. Characterisation of a MOSFET-based detector for dose measurement under megavoltage electron beam radiotherapy

    Science.gov (United States)

    Jong, W. L.; Ung, N. M.; Tiong, A. H. L.; Rosenfeld, A. B.; Wong, J. H. D.

    2018-03-01

    The aim of this study is to investigate the fundamental dosimetric characteristics of the MOSkin detector for megavoltage electron beam dosimetry. The reproducibility, linearity, energy dependence, dose rate dependence, depth dose measurement, output factor measurement, and surface dose measurement under megavoltage electron beam were tested. The MOSkin detector showed excellent reproducibility (>98%) and linearity (R2= 1.00) up to 2000 cGy for 4-20 MeV electron beams. The MOSkin detector also showed minimal dose rate dependence (within ±3%) and energy dependence (within ±2%) over the clinical range of electron beams, except for an energy dependence at 4 MeV electron beam. An energy dependence correction factor of 1.075 is needed when the MOSkin detector is used for 4 MeV electron beam. The output factors measured by the MOSkin detector were within ±2% compared to those measured with the EBT3 film and CC13 chamber. The measured depth doses using the MOSkin detector agreed with those measured using the CC13 chamber, except at the build-up region due to the dose volume averaging effect of the CC13 chamber. For surface dose measurements, MOSkin measurements were in agreement within ±3% to those measured using EBT3 film. Measurements using the MOSkin detector were also compared to electron dose calculation algorithms namely the GGPB and eMC algorithms. Both algorithms were in agreement with measurements to within ±2% and ±4% for output factor (except for the 4 × 4 cm2 field size) and surface dose, respectively. With the uncertainties taken into account, the MOSkin detector was found to be a suitable detector for dose measurement under megavoltage electron beam. This has been demonstrated in the in vivo skin dose measurement on patients during electron boost to the breast tumour bed.

  6. External audit in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Thwaites, D.I.; Western General Hospital, Edinburgh

    1996-01-01

    Quality audit forms an essential part of any comprehensive quality assurance programme. This is true in radiotherapy generally and in specific areas such as radiotherapy dosimetry. Quality audit can independently test the effectiveness of the quality system and in so doing can identify problem areas and minimize their possible consequences. Some general points concerning quality audit applied to radiotherapy are followed by specific discussion of its practical role in radiotherapy dosimetry, following its evolution from dosimetric intercomparison exercises to routine measurement-based on-going audit in the various developing audit networks both in the UK and internationally. Specific examples of methods and results are given from some of these, including the Scottish+ audit group. Quality audit in radiotherapy dosimetry is now well proven and participation by individual centres is strongly recommended. Similar audit approaches are to be encouraged in other areas of the radiotherapy process. (author)

  7. Large-angle inclusive production of protons, antiprotons and kaons, and particle composition at the CERN ISR

    CERN Document Server

    Alper, B; Booth, P; Bulos, F; Carroll, L J; Damgaard, G; Duff, Brian G; Heymann, Franz F; Jackson, J N; Jarlskog, G; Jönsson, L B; Klovning, A; Leistam, L; Lillethun, E; Lynch, G; Prentice, M; Quarrie, D; von Dardel, Guy F; Weiss, J M

    1973-01-01

    The production cross-sections for protons, antiprotons and kaons in proton-proton collisions at centre-of-mass energies square root s=30.6 and 52.8 GeV at large angles and for the transverse momentum range p /sub T/<1.2 GeV/c for protons and antiprotons and 0.2

    measured. The charged particle composition is given in the range 0.2

  8. The Information Needs of New Radiotherapy Patients: How to Measure? Do They Want to Know Everything? And if Not, Why?

    International Nuclear Information System (INIS)

    Zeguers, Maaike; Haes, Hanneke C.J.M. de; Zandbelt, Linda C.; Hoeven, Claartje L. ter; Franssen, Sanne J.; Geijsen, Debbie D.; Koning, Caro C.E.; Smets, Ellen M.A.

    2012-01-01

    Purpose: To establish 1) further psychometric properties of the information preference for radiotherapy patients scale (IPRP); 2) what information new radiotherapy patients want to receive; 3) which patients have a lower information need. Methods and Materials: Eligible patients (n = 159; response rate 54%) of 15 radiation oncologists completed the IPRP and provided background characteristics before their first radiotherapy consultation. Exclusion criteria were: age <18 years, having undergone radiotherapy before, unable to read and write Dutch, cognitive problems or a brain tumor. Results: Reliability (Cronbach’s alpha 0.84–0.97) and concurrent validity (r from .39 to .57, p < 0.001) of the subscales of the IPRP were good. New radiotherapy patients want extensive information about their disease, treatment, procedures, side effects, and prognosis (mean scores between 4.1 and 4.4 on a scale from 1 to 5) but less information about psychosocial issues (mean = 3.4). Patients who are older and male, have lung or rectal cancer, more difficulty understanding and a higher trait anxiety level, need less information. Conclusions: The IPRP can reliably and validly address information needs of patients undergoing radiation treatment. Most new radiotherapy patients want much information. Yet, information giving should be tailored according to their background, understanding and anxiety.

  9. Assessing measurement invariance of a health-related quality-of-life questionnaire in radiotherapy patients

    NARCIS (Netherlands)

    King-Kallimanis, B.L.; ter Hoeven, C.; de Haes, H.C.; Smets, E.M.; Koning, C.C.E.; Oort, F.

    2012-01-01

    Objective: If the assumption of measurement invariance is not tested, we cannot be sure whether differences observed are due to true differences in health-related quality-of-life (HRQoL), or are measurement artifacts. We aim to investigate this assumption in a sample of heterogeneous cancer

  10. Search for Resonances in the Photoproduction of Proton-Antiproton Pairs

    Energy Technology Data Exchange (ETDEWEB)

    Stokes, Burnham [Florida State Univ., Tallahassee, FL (United States)

    2006-01-01

    Results are reported on the reaction γp → p$\\bar{p}$p with beam energy in the range 4.8-5.5 GeV. The data were collected at the Thomas Jefferson National Accelerator Facility in CLAS experiment E01-017(G6C). The focus of this study is an understanding of the mechanisms of photoproduction of proton-antiproton pairs, and to search for intermediate resonances, both narrow and broad, which decay to p$\\bar{p}$. The total measured cross section in the photon energy range 4.8-5.5 GeV is σ = 33 ± 2 nb. Measurement of the cross section as a function of energy is provided. An upper limit on the production of a narrow resonance state previously observed with a mass of 2.02 GeV/c2 is placed at 0.35 nb. No intermediate resonance states were observed. Meson exchange production appears to dominate the production of the proton-antiproton pairs.

  11. High precision spectroscopy of pionic and antiprotonic atoms; Spectroscopie de precision des atomes pioniques et antiprotoniques

    Energy Technology Data Exchange (ETDEWEB)

    El-Khoury, P

    1998-04-15

    The study of exotic atoms, in which an orbiting electron of a normal atom is replaced by a negatively charged particle ({pi}{sup -}, {mu}{sup -}, p, {kappa}{sup -}, {sigma}{sup -},...) may provide information on the orbiting particle and the atomic nucleus, as well as on their interaction. In this work, we were interested in pionic atoms ({pi}{sup -14} N) on the one hand in order to determine the pion mass with high accuracy (4 ppm), and on the other hand in antiprotonic atoms (pp-bar) in order to study the strong nucleon-antinucleon interaction at threshold. In this respect, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high stop density for particles in gas targets at low pressure. Using curved crystals, an extended X-ray source could be imaged onto the detector. Charge-Coupled Devices were used as position sensitive detectors in order to measure the Bragg angle of the transition to a high precision. The use of gas targets resolved the ambiguity owing to the number of K electrons for the value of the pion mass, and, for the first time, strong interaction shift and broadening of the 2p level in antiprotonic hydrogen were measured directly. (author)

  12. Meas.of the Ratio Between Double and Single Ionization of Helium for Antiprotons

    CERN Multimedia

    2002-01-01

    The aim of this experiment is to measure the ratio between double and single ionization of helium by antiprotons in the energy range $>$~3~MeV. Comparison with already existing proton data will yield information on the mechanisms for double ionization, which could not be extracted from previous comparisons between ratios measured for equivelocity electrons and protons. The most basic information to be obtained from an antiproton experiment will be the amount of correlation existing between the two electrons in the ground-state helium atom.\\\\ \\\\ The equipment consists of a gas cell, which employs slow-ion collection via the so-called condenser-plate method for the absolute sum of partial-ionization cross sections and determination of the relative contribution of multiple charged ions by TOF. The gas cell has movable entrance and exit slits and a grid system to account for secondary emission from the collection of slow ions. Together with a field of 800~V/cm in the collision region, the potentials of the TOF sp...

  13. Search for Cosmic-Ray Antiproton Origins and for Cosmological Antimatter with BESS

    Science.gov (United States)

    Yamamoto, A.; Mitchell, J. W.; Yoshimura, K.; Abe, K.; Fuke, H.; Haino, S.; Hams, T.; Hasegawa, M.; Horikoshi, A.; Itazaki, A.; hide

    2011-01-01

    The balloon-borne experiment with a superconducting spectrometer (BESS) has performed cosmic-ray observations as a US-Japan cooperative space science program, and has provided fundamental data on cosmic rays to study elementary particle phenomena in the early Universe. The BESS experiment has measured the energy spectra of cosmic-ray antiprotons to investigate signatures of possible exotic origins such as dark matter candidates or primordial black holes. and searched for heavier antinuclei that might reach Earth from antimatter domains formed in the early Universe. The apex of the BESS program was reached with the Antarctic flight of BESS-Polar II, during the 2007- 2008 Austral Summer, that obtained over 4.7 billion cosmic-ray events from 24.5 days of observation. The flight took place at the expected solar minimum, when the sensitivity of the low-energy antiproton measurements to a primary source is greatest. Here, we report the scientific restults, focusing on the long-duration flights of BESS-Polar I (2004) and BESS-Polar II (2007-2008).

  14. Measurement of the Bottom Quark Production Cross-Section in Proton-Antiproton Collisions at a Center-of-Mass Energy 630-GeV Using Muons with Associated Jets

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Kevin Patrick [Arizona U.

    1999-01-01

    We have measured the b-quark production cross section for |y| < 1 using a sample of muons with associated jets collected with the DØ detector in $p\\bar{p}$ collisions at $\\sqrt{s} = 630 GeV$ at the Fermilab Tevatron. The measured b-quark cross section is consistent in shape with $O {(\\alpha^3_s)}$ QCD predictions, but exceeds them in normalization by roughly a factor of 2.5.

  15. Towards a gravity measurement on cold antimatter atoms

    CERN Document Server

    Caravita, R; Amsler, C; Ariga, A; Ariga, T; Bonomi, G; Bräunig, P; Bremer, J; Brusa, R S; Cabaret, L; Caccia, M; Castelli, F; Cerchiari, G; Chlouba, K; Cialdi, S; Comparat, D; Consolati, G; Demetrio, A; Di Noto, L; Doser, M; Dudarev, A; Ereditato, A; Evans, C; Ferragut, R; Fesel, J; Fontana, A; Forslund, O K; Gerber, S; Giammarchi, M; Gligorova, A; Gninenko, S; Guatieri, F; Haider, S; Holmestad, H; Huse, T; Jernelv, I L; Jordan, E; Kaltenbacher, T; Kellerbauer, A; Kimura, M; Koetting, T; Krasnicky, D; Lagomarsino, V; Lansonneur, P; Lebrun, P; Lehner, S; Liberadzka, J; Malbrunot, C; Mariazzi, S; Marx, L; Matveev, V; Mazzotta, Z; Nebbia, G; Nedelec, P; Oberthaler, M; Pacifico, N; Pagano, D; Penasa, L; Petracek, V; Pistillo, C; Prelz, F; Prevedelli, M; Ravelli, L; Resch, L; Rienäcker, B; Røhne, O M; Rosenberger, S; Rotondi, A; Sacerdoti, M; Sandaker, H; Santoro, R; Scampoli, P; Sorrentino, F; Spacek, M; Storey, J; Strojek, I M; Testera, G; Tietje, I; Vamosi, S; Widmann, E; Yzombard, P; Zavatarelli, S; Zmeskal, J

    2016-01-01

    The present status of the AEGIS experiment at CERN (AD-06), on the way of forming anti-hydrogen for a first gravity measurement, is reviewed. Recent results in trapping and cooling positrons and antiprotons in the main electromagnetic traps are presented, including the storage time measurement obtained during the 2014 run with antiprotons, the observation of centrifugal separation of a mixed antiproton/electron plasma and positron accumulation and transfer results obtained during 2015.

  16. Measurement of Top Quark Properties and Search for the Standard Model Higgs Boson in Proton Anti-Proton Collisions at $\\sqrt{s}$ = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Ebina, Koji [Waseda Univ., Shinjuku (Japan)

    2011-03-01

    We present a measurement of the top quark mass and of the top-antitop ( tf) pair production cross section and a search for the Standard Model Higgs boson with CDF II Detector in pp collisions at $\\sqrt{s}$ = 1.96 TeV. The integrated luminosity of 2.9 $fb^{-1}$ is used for top-antitop pair production cross section and top quark mass measurement. We adopt a neural-network algorithm to select candidate events from six or more jets. At least one of these jets should be required to be b jet, as identified by the reconstruction of a secondary vertex inside the jet. The mass measurement is based on a likelihood fit incorporating reconstructed mass distributions representative of signal and background, where the absolute jet energy scale (JES) is measured simultaneously with the top quark mass. The measurement yields a value of 174.8 ± 2.4 (stat + JES) $^{+1.2}_{-1.0}$ (syst) GeV/$c^2$ , where the uncertainty from the absolute jet energy scale is evaluated together with the statistical uncertainty. The procedure also measures the amount of signal from which we derive a cross section, $\\sigma_{t\\bar{t}}$ = 7.2 ± 0.5 (stat) ±1.0 (syst) ± 0.4 (lum) $pb$, for the measured values of top quark mass and JES. Top quark mass and W boson mass constrain the mass of the Standard Model Higgs boson, indirectly. This prediction implies MH = 89 $^{+35}_{-26}$GeV/$c^2$ (68% confidence level) as of July 2010. Therefore, we concentrate on the Standard Model Higgs mass search region with $\\le$ 135 GeV / $c^2$ . Then, we search for the Standard Model Higgs boson associated with vector boson using the decay modes consisting of leptons only: Signal processes are $WH \\to \\ell \

  17. Cosmic ray propagation in a diffusion model: a new estimation of the diffusion parameters and of the secondary antiprotons flux

    International Nuclear Information System (INIS)

    Maurin, D.

    2001-02-01

    Dark matter is present at numerous scale of the universe (galaxy, cluster of galaxies, universe in the whole). This matter plays an important role in cosmology and can not be totally explained by conventional physic. From a particle physic point of view, there exists an extension of the standard model - supersymmetry - which predicts under certain conditions the existence of new stable and massive particles, the latter interacting weakly with ordinary matter. Apart from direct detection in accelerators, various indirect astrophysical detection are possible. This thesis focuses on one particular signature: disintegration of these particles could give antiprotons which should be measurable in cosmic rays. The present study evaluates the background corresponding to this signal i. e. antiprotons produced in the interactions between these cosmic rays and interstellar matter. In particular, uncertainties of this background being correlated to the uncertainties of the diffusion parameter, major part of this thesis is devoted to nuclei propagation. The first third of the thesis introduces propagation of cosmic rays in our galaxy, emphasizing the nuclear reaction responsibles of the nuclei fragmentation. In the second third, different models are reviewed, and in particular links between the leaky box model and the diffusion model are recalled (re-acceleration and convection are also discussed). This leads to a qualitative discussion about information that one can infer from propagation of these nuclei. In the last third, we finally present detailed solutions of the bidimensional diffusion model, along with constrains obtained on the propagation parameters. The latter is applied on the antiprotons background signal and it concludes the work done in this thesis. The propagation code for nuclei and antiprotons used here has proven its ability in data analysis. It would probably be of interest for the analysis of the cosmic ray data which will be taken by the AMS experiment on

  18. Novel Dark Matter Constraints from Antiprotons in Light of AMS-02.

    Science.gov (United States)

    Cuoco, Alessandro; Krämer, Michael; Korsmeier, Michael

    2017-05-12

    We evaluate dark matter (DM) limits from cosmic-ray antiproton observations using the recent precise AMS-02 measurements. We properly take into account cosmic-ray propagation uncertainties, fitting DM and propagation parameters at the same time and marginalizing over the latter. We find a significant indication of a DM signal for DM masses near 80 GeV, with a hadronic annihilation cross section close to the thermal value, ⟨σv⟩≈3×10^{-26}  cm^{3} s^{-1}. Intriguingly, this signal is compatible with the DM interpretation of the Galactic center gamma-ray excess. Confirmation of the signal will require a more accurate study of the systematic uncertainties, i.e., the antiproton production cross section, and the modeling of the effect of solar modulation. Interpreting the AMS-02 data in terms of upper limits on hadronic DM annihilation, we obtain strong constraints excluding a thermal annihilation cross section for DM masses below about 50 GeV and in the range between approximately 150 and 500 GeV, even for conservative propagation scenarios. Except for the range around ∼80  GeV, our limits are a factor of ∼4 stronger than the limits from gamma-ray observations of dwarf galaxies.

  19. A Good Statistics Study of Antiproton Interactions with Nuclei

    CERN Multimedia

    2002-01-01

    This experiment extends the study of inclusive pion production and the correlation between pions which result from hadron-nucleus collisions at intermediate and high energies to the antiproton-nucleus system. It is part of a long term systematic search for exotic nuclear phenomena. The correlation data will be used to extract, via pion interferometry, the size and coherence of the annihilation source in nuclei. In addition, the reaction @* + A @A p + A* will be studied to look for structure in the proton spectra which antiproton-nucleus bound states.\\\\ \\\\ The experimental system is based on a flexible, broad range, large acceptance (1~steradian) spectrometer which consists of an 80~cm diameter dipole magnet surrounded with detector arrays. These detectors provide momentum, energy loss, Cerenkov and time of flight information for up to ten ejectiles per event. Momentum resolution varies from 1\\% to 3\\%, depending on energy.

  20. Dark matter for excess of AMS-02 positrons and antiprotons

    Directory of Open Access Journals (Sweden)

    Chuan-Hung Chen

    2015-07-01

    Full Text Available We propose a dark matter explanation to simultaneously account for the excess of antiproton-to-proton and positron power spectra observed in the AMS-02 experiment while having the right dark matter relic abundance and satisfying the current direct search bounds. We extend the Higgs triplet model with a hidden gauge symmetry of SU(2X that is broken to Z3 by a quadruplet scalar field, rendering the associated gauge bosons stable weakly-interacting massive particle dark matter candidates. By coupling the complex Higgs triplet and the SU(2X quadruplet, the dark matter candidates can annihilate into triplet Higgs bosons each of which in turn decays into lepton or gauge boson final states. Such a mechanism gives rise to correct excess of positrons and antiprotons with an appropriate choice of the triplet vacuum expectation value. Besides, the model provides a link between neutrino mass and dark matter phenomenology.

  1. Precocious scaling in antiproton-proton scattering at low energies

    International Nuclear Information System (INIS)

    Ion, D.B.; Petrascu, C.; Topor Pop, V.; Popa, V.

    1993-08-01

    The scaling of the diffraction peak in antiproton-proton scattering has been investigated from nera threshold up to 3 GeV/c laboratory momenta. It was shown that the scaling of the differential cross sections are evidentiated with a surprising accuracy not only at high energies, but also at very low ones (e.g. p LAB = 0.1 - 0.5 GeV/c), beyond the resonance and exotic resonance regions. This precocious scaling strongly suggests that the s-channel helicity conservation (SCHC) can be a peculiar property that should be tested in antiproton-proton interaction not only at high energies but also at low energy even below p LAB = 1 GeV/c. (author). 36 refs, 9 figs

  2. Commissioning of Fermilab's Electron Cooling System for 8-GeV Antiprotons

    CERN Document Server

    Nagaitsev, Sergei; Burov, Alexey; Carlson, Kermit; Gai, Wei; Gattuso, Consolato; Hu, Martin; Kazakevich, Grigory; Kramper, Brian J; Kroc, Thomas K; Leibfritz, Jerry; Prost, Lionel; Pruss, Stanley M; Saewert, Greg W; Schmidt, Chuck; Seletsky, Sergey; Shemyakin, Alexander V; Sutherland, Mary; Tupikov, Vitali; Warner, Arden

    2005-01-01

    A 4.3-MeV electron cooling system has been installed at Fermilab in the Recycler antiproton storage ring and is being currently commissioned. The cooling system is designed to assist accumulation of 8.9-GeV/c antiprotons for the Tevatron collider operations. This paper will report on the progress of the electron beam commissioning effort as well as on detailed plans of demonstrating the cooling of antiprotons.

  3. The Antiproton Accumulator and Collector and the discovery of the W & Z intermediate vector bosons

    CERN Document Server

    Chohan, Vinod

    2016-01-01

    The following sections are included: Preface ; Brief outline of the overall scheme for antiprotons of the SPS as a collider ; Antiproton production and accumulation ; The AA and AC storage rings ; Stochastic cooling and stacking ; Post-acceleration of antiprotons and beams for SPS Collider ; Proton test beams for the AA and AC from the PS ; The W and Z discoveries and the Nobel Prize ; Accumulator performance ; Acknowledgements and conclusions ; References

  4. Portal dose measurement in radiotherapy using an electronic portal imaging device (EPID)

    International Nuclear Information System (INIS)

    Heijmen, B.J.M.; Pasma, K.L.; Kroonwijk, M.; Boer, J.C.J. de; Visser, A.G.; Huizenga, H.; Althof, V.G.M.

    1995-01-01

    Physical characteristics of a commercially available electronic portal imaging device (EPID), relevant to dosimetric applications in high-energy photon beams, have been investigated. The EPID basically consists of a fluorescent screen, mirrors and a CCD camera. Image acquisition for portal dose measurement has been performed with a special procedure, written in the command language that comes with the system. The observed day-to-day variation in local EPID responses, i.e. measured grey scale value (EPID signal) per unit of delivered portal dose, is 0.4% (1 SD); day-to-day variations in relative EPID responses (e.g. normalized to the on-axis response) are within 0.2% (1 SD). Measured grey scale values are linearly proportional to transmitted portal doses with a proportionality constant which is independent of the thickness of a flat, water-equivalent absorber in the beam, but which does significantly depend on the size of the applied X-ray beam. It is shown that the observed increase in EPID response with increasing field size is mainly due to contributions to the EPID signals from scattered light: visible photons produced by the X-ray beam in a point of the fluorescent screen not only generate a grey scale value in the corresponding point of the EPID image, but also lead (due to scatter from components of the EPID structure onto the CCD chip) to an increased grey scale value at all other points of the image. (Author)

  5. A practical and theoretical definition of very small field size for radiotherapy output factor measurements.

    Science.gov (United States)

    Charles, P H; Cranmer-Sargison, G; Thwaites, D I; Crowe, S B; Kairn, T; Knight, R T; Kenny, J; Langton, C M; Trapp, J V

    2014-04-01

    This work introduces the concept of very small field size. Output factor (OPF) measurements at these field sizes require extremely careful experimental methodology including the measurement of dosimetric field size at the same time as each OPF measurement. Two quantifiable scientific definitions of the threshold of very small field size are presented. A practical definition was established by quantifying the effect that a 1 mm error in field size or detector position had on OPFs and setting acceptable uncertainties on OPF at 1%. Alternatively, for a theoretical definition of very small field size, the OPFs were separated into additional factors to investigate the specific effects of lateral electronic disequilibrium, photon scatter in the phantom, and source occlusion. The dominant effect was established and formed the basis of a theoretical definition of very small fields. Each factor was obtained using Monte Carlo simulations of a Varian iX linear accelerator for various square field sizes of side length from 4 to 100 mm, using a nominal photon energy of 6 MV. According to the practical definition established in this project, field sizes ≤ 15 mm were considered to be very small for 6 MV beams for maximal field size uncertainties of 1 mm. If the acceptable uncertainty in the OPF was increased from 1.0% to 2.0%, or field size uncertainties are 0.5 mm, field sizes ≤ 12 mm were considered to be very small. Lateral electronic disequilibrium in the phantom was the dominant cause of change in OPF at very small field sizes. Thus the theoretical definition of very small field size coincided to the field size at which lateral electronic disequilibrium clearly caused a greater change in OPF than any other effects. This was found to occur at field sizes ≤ 12 mm. Source occlusion also caused a large change in OPF for field sizes ≤ 8 mm. Based on the results of this study, field sizes ≤ 12 mm were considered to be theoretically very small for 6 MV beams. Extremely

  6. Selected Papers on Low-Energy Antiprotons and Possible Applications

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Robert [Fermilab

    1998-09-19

    The only realistic means by which to create a facility at Fermilab to produce large amounts of low energy antiprotons is to use resources which already exist. There is simply too little money and manpower at this point in time to generate new accelerators on a time scale before the turn of the century. Therefore, innovation is required to modify existing equipment to provide the services required by experimenters.

  7. Prospects for testing Lorentz and CPT symmetry with antiprotons.

    Science.gov (United States)

    Vargas, Arnaldo J

    2018-03-28

    A brief overview of the prospects of testing Lorentz and CPT symmetry with antimatter experiments is presented. The models discussed are applicable to atomic spectroscopy experiments, Penning-trap experiments and gravitational tests. Comments about the sensitivity of the most recent antimatter experiments to the models reviewed here are included.This article is part of the Theo Murphy meeting issue 'Antiproton physics in the ELENA era'. © 2018 The Author(s).

  8. The Production and Study of Antiprotons and Cold Antihydrogen

    Science.gov (United States)

    2010-11-10

    to sustain this unique antimatter research study of antiprotons and antihydrogen, the annihilation of which produce the maximum energy per unit mass...The practical goal is to develop the unusual techniques required to produce and store atoms made entirely of antimatter , given that the slightest...matter and antimatter atoms to extremely high precision – promising to be the highest precision test of the fundamental CPT theorem with leptons and

  9. Measurement of the Top Quark Mass in the All-Hadronic Channel at Proton Antiproton Collisions at $\\sqrt{s}$ = 1.96 TeV with CDF II

    Energy Technology Data Exchange (ETDEWEB)

    Margaroli, Fabrizio [Univ. of Bologna (Italy)

    2007-01-01

    We report a measurement of the top quark mass in the all-hadronic channel with the upgraded Collider Detector at Fermilab using an integrated luminosity of 1.02 $fb^{-1}$ . Top quarks are produced mostly in pairs at the Tevatron Collider; they subsequently decay almost 100% of the time in a W boson and a b quark each. Final states are classified according to the decays of the W bosons. Here we study only those events in which both W's decay into quark pairs. This channel has the advantage of a large branching ratio and of being fully reconstructed. On the other hand the signal is overwhelmed by a background which surpasses it by three orders of magnitude even after the requirement of a specific trigger. A neural network is thus used to discriminate signal from background events in order to achieve a good signal over background ratio. We look for a variable which is strongly correlated with the top quark mass, and compare the corresponding distribution in the data to signal and background templates in order to measure the top quark mass. Here is an outline of the following of this work: Chapter 1 presents an introduction to the path that lead to the formalization of the Standard Model of fundamental interactions. We discuss in Chapter 2 the need for a 6th quark in the Standard Model, the phenomenology of the top quark and a summary of the current experimental knowledge of its properties, and motivate the need for a precise measurement of its mass. In Chapter 3 we describe the experimental apparatus needed to produce the top quarks, i.e. the Tevatron Collider, and the detector which collects the data analyzed in this work, CDF II. Chapter 4 describes how CDF II interprets the output from the various subdetectors and translate them into the physics objects which are needed for the measurement. In Chapter 5 we present how we overcome the problem of the huge background which overwhelms the top production by using for the first time in this channel a neural network

  10. Cooling effect on hot antiproton plasma using buffer gas cloud. Simbuca - setup and simulations

    CERN Document Server

    Roshkovski, Dejan

    2014-01-01

    In this work I investigated the sympathetic cooling effect of antipro- tons with a plasma of charged anions in a Penning trap. From the AD (antiproton decelerator) antiprotons are decelerated to 5.5MeV. To get them further decelerated we trap the antiprotons inside the penning trap where we cool them down even further using a buffer gas which consists of charged plasma anions which helps us cool the antiprotons. For this work I used the open source simulations program Simbuca

  11. A Measurement of the Inclusive Z / γ* → μ+ μ- Cross-Section and Study of W and Z Events in proton - anti-proton Collisions at D0

    Energy Technology Data Exchange (ETDEWEB)

    Nurse, Emily L. [Univ. of Manchester (United Kingdom)

    2005-01-01

    A measurement of the inclusive Z/γ* → μ+ μ- cross section for Mμμ > 40 GeV at √s = 1.96 TeV is presented. The measurement is performed using a data sample corresponding to an integrated luminosity of 147.7 pb-1, collected with the D0 detector at the Tevatron, Fermilab, between September 2002 and October 2003. A total of 14352 di-muon events are selected and a final result of σ(Z/γ*) = 327.8 ± 3.4(stat.) ± 8.4(syst.) ± 21.3(lumi.) pb is obtained. Correcting the number of di-muon events by a factor of 0.885 ± 0.015 for the contribution from pure γ* exchange and Z/γ* interference, the inclusive Z → μ+ μ- cross section is found to be: σ(Z) = 290.1 ± 3.0(stat.) ± 7.4(syst.) ± 18.9(lumi.) pb. Finally, comparisons of W and Z boson pT distributions as measured with D0 during Run I of the Tevatron are compared to HERWIG and MC@NLO predictions. Relevant parameters in the simulations are tuned to obtain the best possible fit to the data. An excellent agreement is found for both HERWIG and MC@NLO.

  12. A measurement of the t anti t production cross section in proton-antiproton collisions at √s=1.96 TeV with the DOe detector at the Tevatron using final states with a muon and jets

    International Nuclear Information System (INIS)

    Klute, M.

    2004-02-01

    A preliminary measurement of the t anti t production cross section at √s=1.96 TeV is presented. The μ-plus-jets final state is analyzed in a data sample of 94 pb -1 and a total of 14 events are selected with a background expectation of 11.7±1.9 events. The measurement yields: σ p anti p→t anti t+X =2.4 -3.5 +4.2 (stat.) -2.6 +2.5 (syst.)±0.3(lumi.) pb. The analysis, being part of a larger effort to re-observe the top quark in Tevatron Run II data and to measure the production cross section, is combined with results from the available analysis channels. The combined result yields: σ p anti p→t anti t+X =8.1 -2.0 +2.2 (stat.) -1.4 +1.6 (syst.)±0.8(lumi.) pb

  13. A measurement of the t anti t production cross section in proton-antiproton collisions at {radical}s=1.96 TeV with the DOe detector at the Tevatron using final states with a muon and jets

    Energy Technology Data Exchange (ETDEWEB)

    Klute, M.

    2004-02-01

    A preliminary measurement of the t anti t production cross section at {radical}s=1.96 TeV is presented. The {mu}-plus-jets final state is analyzed in a data sample of 94 pb{sup -1} and a total of 14 events are selected with a background expectation of 11.7{+-}1.9 events. The measurement yields: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X}=2.4{sub -3.5}{sup +4.2}(stat.){sub -2.6}{sup +2.5}(syst.){+-}0.3(lumi.) pb. The analysis, being part of a larger effort to re-observe the top quark in Tevatron Run II data and to measure the production cross section, is combined with results from the available analysis channels. The combined result yields: {sigma}{sub p} {sub anti} {sub p{yields}}{sub t} {sub anti} {sub t+X}=8.1{sub -2.0}{sup +2.2}(stat.){sub -1.4}{sup +1.6}(syst.){+-}0.8(lumi.) pb.

  14. Measurement of the polarization for antiproton--proton annihilation into charged. pi. and K pairs between 1. 0 and 2. 2 GeV/c. [Differential cross sections, asymmetries

    Energy Technology Data Exchange (ETDEWEB)

    Carter, A.A.; Coupland, M.; Eisenhandler, E.

    1976-01-01

    The polarization parameter for the interactions anti pp ..-->.. ..pi../sup -/..pi../sup +/ and anti pp ..-->.. K/sup -/K/sup +/ was measured over essentially the full angular range at 11 momenta between 1.0 and 2.2 GeV/c. A proton target polarized perpendicular to the scattering plane was used. The experiment measured the angles and momenta of both outgoing particles using wire spark chambers and the field of the polarized target magnet. Between 1000 and 5300 ..pi../sup -/..pi../sup +/ events, and 140 and 1300 K/sup -/K/sup +/ events, were measured at each momentum. As a check, one obtained differential cross sections for anti pp ..-->.. ..pi../sup -/..pi../sup +/ which are in excellent agreement with previous results. The polarizations for both channels are very large and positive over much of the angular range. Preliminary results of a fit to the cross sections and asymmetries for anti pp ..-->.. ..pi../sup -/..pi../sup +/ show strong evidence for three new resonances at 2.14, 2.36, and 2.40 GeV/c/sup 2/.

  15. Measurement and production of electron deflection using a sweeping magnetic device in radiotherapy

    International Nuclear Information System (INIS)

    Damrongkijudom, N.; Oborn, B.; Rosenfeld, A.; Butson, M.

    2006-01-01

    The deflection and removal of high energy electrons produced by a medical linear accelerator has been attained by a Neodymium Iron Boron (NdFeB) permanent magnetic deflector device. This work was performed in an attempt to confirm the theoretical amount of electron deflection which could be produced by a magnetic field for removal of electrons from a clinical x-ray beam. This was performed by monitoring the paths of mostly monoenergetic clinical electron beams (6MeV to 20MeV) swept by the magnetic fields using radiographic film and comparing to first order deflection models. Results show that the measured deflection distance for 6 MeV electrons was 18 ± 6 cm and the calculated deflection distance was 21.3 cm. For 20 MeV electrons, this value was 5 ± 2 cm for measurement and 5.1 cm for calculation. The magnetic fields produced can thus reduce surface dose in treatment regions of a patient under irradiation by photon beams and we can predict the removal of all electron contaminations up to 6 MeV from a 6 MV photon beam with the radiation field size up to 10 x 10 cm 2 . The model can also estimate electron contamination still present in the treatment beam at larger field sizes

  16. Using an electronic portal imaging device for exit dose measurements in radiotherapy

    International Nuclear Information System (INIS)

    Ganowicz, M.; Wozniak, B.; Bekman, A.; Maniakowski, Z.

    2003-01-01

    To present a method of determining the exit dose with the use of an electronic portal imaging device (EPID). The device used was the Portal Vision LC250 (Varian). The EPID signals on the central beam axis have been related to the exit dose. The exit dose measurements were performed with the ionisation chamber in the slab phantom at the distance of dose maximum from the exit surface of the phantom. EPID reading was investigated as a function of field size, phantom thickness and source-detector distance. The relation between dose rate and the EPID reading is described with empirical functions applicable to the obtained data. The exit dose is calculated from the EPID reading as a product of the calibration factor and appropriate correction factors. The determination of the exit dose rate from the EPID signal requires the knowledge of many parameters and earlier determination of essential characteristics. (author)

  17. Measurement of the top pair-production cross section in the dilepton channel in proton-antiproton collisions at a $\\sqrt{s}$ = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Coca, Mircea Norocel [Univ. of Rochester, NY (United States)

    2004-01-01

    The top quark was discovered by CDF and D0 in 1995, in Run I. This thesis presents the results of the top production cross-section measurement, in the dilepton channel, using data taken at the Collider Detector at Fermilab (CDF) in p$\\bar{p}$ collisions, at a center-of-mass energy of √ s =1.96 TeV. The dataset represents an integrated luminosity of 193 pb-1 and was collelcted between the period March 2002 - September 2003. Thirteen events were observed (1 e/e, 9 e/ μ , 3 μ/μ ), passing the selection requirements, with an estimated background of 2.8 ± 0.7 events. These are used to measure a t$\\bar{t}$ ross-section of σ t$\\bar{t}$ = 8.4_ $+3.2\\atop{-2.7}$ (stat)_ $+1.5\\atop{- 1.1}$ (syst) ± 0.5 (lum)pb. This is in a good agreement with the Standard Model prediction of σ$t\\bar{t}$ = 6.7_ $+0.71\\atop{- 0.88}$ pb, for a top quark mass of 175 GeV/c2 . Also few kinematical distributions are compared with the Standard Model and found to agree well.

  18. Measurement of the Single Top Quark Cross Section in the Lepton Plus Jets Final State in Proton-Antiproton Collisions at a Center of Mass Energy of 1.96 TeV Using the CDF II Detector

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhenbin [Baylor Univ., Waco, TX (United States)

    2012-01-01

    We present a measurement of the single top quark cross section in the lepton plus jets final state using an integrated luminosity corresponding to 7.5 fb-1 of p\\bar p collision data collected by the Collider Detector at Fermilab. The single top candidate events are identified by the signature of a charged lepton, large missing transverse energy, and two or three jets with at least one of them identified as originating from a bottom quark. A new Monte Carlo generator POWHEG is used to model the single top quark production processes, which include s-channel, t-channel, and Wt-channel. A neural network multivariate method is exploited to discriminate the single top quark signal from the comparatively large backgrounds. We measure a single top production cross section of $3.04^{+0.57}_{-0.53} (\\mathrm{stat.~+~syst.})$ pb assuming $m_{\\rm top}=172.5$~GeV/$c^2$. In addition, we extract the CKM matrix element value $|V_{tb}|=0.96\\pm 0.09~(\\mathrm{stat.~+~syst.})\\ ± 0.05~(\\mathrm{theory})$ and set a lower limit of $|V_{tb}|>0.78$ at the 95% credibility level.

  19. A Measurement of the B Quark and Neutral B Meson Production Cross-Sections in Proton - Antiproton Collisions at a Center-of-Mass Energy of 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Vejcik, III, Steve [Johns Hopkins Univ., Baltimore, MD (United States)

    1992-08-01

    The measurement of the b quark and $B^0$ meson production cross sections in pp collisions at $\\sqrt{s}$ = 1.8 TeV for $\\mid y \\mid$ < 1.0 and $P_T(B^0$) > 9.0 GeV /c, $P_T$(b) > 11.5 GeV /c is reported. The $B^0$ sample was tagged with the decay chain $B^0 \\to J /\\psi K^{0*}$, $J/ \\psi \\to \\mu^+ \\mu^-, K^{0*} \\to K^{\\pm} \\pi^{\\mp}$ from a sample of pp collisions with an integrated luminosity of 4.3 $pb^{-1}$. The results are compared to the values predicted from O($\\alpha_{s^3}$) perturbative Quantum Chromodynamics and indicate a production rate for b quarks which is in excess of that predicted. Implications of the result are that the next-to-leading order calculations are not yet capable of precisely predicting heavy quark production rates. The same calculations are presently utilized to estimate the production cross section of top quarks. While these calculations may be more reliable for top quarks, the discrepancy between the calculated and measured b quark production cross section could indicate that present upper limits on the top quark mass are conservative. This thesis was prepared under the guidance of Professor Bruce Barnett.

  20. Measurement of the top-antitop quark pair differential cross section with respect to the invariant mass of the pair in proton-antiproton collisions at a center of mass energy of 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Bridgeman, Alice Patricia [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2008-01-01

    I present a measurement of the t$\\bar{t}$ differential cross section, dσ/dMt$\\bar{t}$, in p$\\bar{p}$ collisions at √s = 1.96 TeV using 2.7 fb-1 of CDF II data. I find that dσ/dMt$\\bar{t}$ is consistent with the Standard Model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions. I set limits on the ratio Κ/MPl in the Randall-Sundrum model by looking for Kaluza Klein gravitons which decay to top quarks. I find Κ/MPl > 0.16 at the 95% confidence level.

  1. Measurement of the top quark pair production cross section in proton-antiproton collisions at a center of mass energy of 1.96 TeV, hadronic top decays with the D0 detector

    Energy Technology Data Exchange (ETDEWEB)

    Hegeman, Jeroen Guido [Univ. of Twente, Enschede (Netherlands)

    2009-01-16

    Of the six quarks in the standard model the top quark is by far the heaviest: 35 times more massive than its partner the bottom quark and more than 130 times heavier than the average of the other five quarks. Its correspondingly small decay width means it tends to decay before forming a bound state. Of all quarks, therefore, the top is the least affected by quark confinement, behaving almost as a free quark. Its large mass also makes the top quark a key player in the realm of the postulated Higgs boson, whose coupling strengths to particles are proportional to their masses. Precision measurements of particle masses for e.g. the top quark and the W boson can hereby provide indirect constraints on the Higgs boson mass. Since in the standard model top quarks couple almost exclusively to bottom quarks (t → Wb), top quark decays provide a window on the standard model through the direct measurement of the Cabibbo-Kobayashi-Maskawa quark mixing matrix element Vtb. In the same way any lack of top quark decays into W bosons could imply the existence of decay channels beyond the standard model, for example charged Higgs bosons as expected in two-doublet Higgs models: t → H+b. Within the standard model top quark decays can be classified by the (lepton or quark) W boson decay products. Depending on the decay of each of the W bosons, t$\\bar{t}$ pair decays can involve either no leptons at all, or one or two isolated leptons from direct W → e$\\bar{v}${sub e} and W → μ$\\bar{v}$μ decays. Cascade decays like b → Wc → e$\\bar{v}$ec can lead to additional non-isolated leptons. The fully hadronic decay channel, in which both Ws decay into a quark-antiquark pair, has the largest branching fraction of all t$\\bar{t}$ decay channels and is the only kinematically complete (i.e. neutrino-less) channel. It lacks, however, the clear isolated lepton signature and is therefore hard to distinguish from the multi-jet QCD background. It

  2. Intercomparison of Dosimeters for Non-Target Organ Dose Measurements in Radiotherapy - Activity of EURADOS WG 9: Radiation Protection in Medicine

    International Nuclear Information System (INIS)

    Miljanic, S.; Knezevic, Z.; Bessieres, I.; Bordy, J.-M.; D'Agostino, E.; d'Errico, F.; di Fulvio, A.; Domingo, C.; Olko, P.; Stolarczyk; Silari, M.; Harrison, R.

    2011-01-01

    It has been known for a long time that patients treated with ionizing radiation carry a risk of developing radiation induced cancer in their lifetimes. It is recognized that cure/survival rates in radiotherapy are increasing, but so are secondary cancers. These occurrences are amplified by the early detection of disease in younger patients. These patients are cured from the primary disease and have long life-expectancies, which increase their chances of developing secondary malignancies. The motivation of the EURADOS Working Group 9 (WG 9) ''Radiation protection dosimetry in medicine'' is to assess undue non-target patient doses in radiotherapy and the related risks of secondary malignancy with the most accredited available methods and with the emphasis on a thorough evaluation of dosimetry methods for the measurements of doses remote from the target volume, in phantom experiments. The development of a unified and comprehensive dosimetry methodology for non-target dose estimation is the key element of the WG9 current work. The first scientific aim is to select and review dosimeters suitable for photon and neutron dosimetry in radiotherapy and to evaluate the characteristics of dosimeters at CEA LIST Saclay in reference clinical LINAC beam. (author)

  3. LEAP: A balloon-borne search for low-energy cosmic ray antiprotons

    Science.gov (United States)

    Moats, Anne Rosalie Myers

    The LEAP (Low Energy Antiproton) experiment is a search for cosmic ray antiprotons in the 120 MeV to 1.2 GeV kinetic energy range. The motivation for this project was the result announced by Buffington et al. (1981) that indicated an anomalously high antiproton flux below 300 MeV; this result has compelled theorists to propose sources of primary antiprotons above the small secondary antiproton flux produced by high energy cosmic ray collisions with nuclei in the interstellar medium. LEAP consisted of the NMSU magnet spectrometer, a time-of-flight system designed at NASA-Goddard, two scintillation detectors, and a Cherenkov counter. Analysis of flight data performed by the high energy astrophysics group at Goddard Space Flight Center revealed no antiproton candidates found in the 120 MeV to 360 MeV range; 3 possible antiproton candidate events were found in the 500 MeV to 1.2 GeV range in an analysis done here at the University of Arizona. However, since it will be necessary to sharpen the calibration on all of the LEAP systems in order to positively identify these events as antiprotons, only an upper limit has been determined at present. Thus, combining the analyses performed at the University of Arizona and NASA-Goddard, 90 percent confidence upper limits of 3.5 x 10-5 in the 120 MeV to 360 MeV range and 2.3 x 10-4 in the 500 MeV to 1.2 GeV range for the antiproton/proton ratio is indicated by the LEAP results. LEAP disagrees sharply with the results of the Buffington group, indicating a low antiproton flux at these energies. Thus, a purely secondary antiproton flux may be adequate at low energies.

  4. Radiotherapy Accidents

    Science.gov (United States)

    Mckenzie, Alan

    A major benefit of a Quality Assurance system in a radiotherapy centre is that it reduces the likelihood of an accident. For over 20 years I have been the interface in the UK between the Institute of Physics and Engineering in Medicine and the media — newspapers, radio and TV — and so I have learned about radiotherapy accidents from personal experience. In some cases, these accidents did not become public and so the hospital cannot be identified. Nevertheless, lessons are still being learned.

  5. Radiotherapy apparatus

    International Nuclear Information System (INIS)

    Leung, P.M.; Webb, H.P.J.

    1985-01-01

    This invention relates to apparatus for applying intracavitary radiotherapy. In previously-known systems radioactive material is conveyed to a desired location within a patient by transporting a chain of balls pneumatically to and from an appropriately inserted applicator. According to this invention a ball chain for such a purpose comprises several radioactive balls separated by non-radioactive tracer balls of radiographically transparent material of lower density and surface hardness than the radioactive balls. The invention also extends to radiotherapy treatment apparatus comprising a storage, sorting and assembly system

  6. Production of ultra slow antiprotons, its application to atomic collisions and atomic spectroscopy-ASACUSA project

    CERN Document Server

    Yamazaki, Y

    1999-01-01

    The atomic spectroscopy and collisions using slow antiprotons (ASACUSA) project aims at studying collision dynamics with slow antiprotons and high precision spectroscopy of antiprotonic atoms. To realize these purposes, the $9 production of high quality ultra slow antiproton beams is essential, which is achieved by the combination of antiproton decelerator (AD) from 3 GeV to 5 MeV, a radio frequency quadrupole (RFQ) decelerator from 5 MeV to 50 keV, and $9 finally an electromagnetic trap from 50 keV to 10 eV. From the atomic physics point of view, an antiproton is an extremely heavy electron and/or a negatively charged proton, i.e., the antiproton is a unique tool to shed light on $9 collision dynamics from the other side of the world. In addition to this fundamentally important feature, the antiproton has also a big practical advantage, i.e., it annihilates with the target nuclei emitting several energetic $9 pions, which provides high detection efficiency with very good time resolution. Many-body effects wh...

  7. Development and psychometric testing of an instrument to measure the patient’s experience of external radiotherapy: The Radiotherapy Experience Questionnaire (RTEQ

    Directory of Open Access Journals (Sweden)

    Kristina Olausson

    2017-09-01

    Conclusion: The RT Experience Questionnaire is a tentatively valid and reliable instrument to measure how patients experience the external RT session process and the environment in the treatment room.

  8. Antiprotonic atoms in gaseous H/sub 2/ and He and in liquid H/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Lindemuth, J.R.; Eckhause, M.; Giovanetti, K.L.; Kane, J.R.; Pandey, M.S.; Rushton, A.M.; Vulcan, W.F.; Welsh, R.E.; Winter, R.G.; Barnes, P.D.; Craig, J.N.; Eisenstein, R.A.; Sherman, J.D.; Sutton, R.B.; Wharton, W.R.; Miller, J.P.; Roberts, B.L.; Kunselman, A.R.; Powers, R.J.

    1984-11-01

    Antiprotons were brought to rest in targets of gaseous H/sub 2/ and gaseous He at temperatures of 30 K and also in a target of liquid H/sub 2/. High-resolution x-ray detectors were used to measure the energies of x rays from p-bar-He and to search for x rays from p-bar-H. The p-bar-He data are compared with similar measurements at different densities and with the theoretical predictions of Landua and Klempt. The p-bar-H data provide upper limits for the yields of nP..-->..1S x rays in liquid and gaseous hydrogen.

  9. Discriminating between antihydrogen and mirror-trapped antiprotons in a minimum-B trap

    CERN Document Server

    Amole, C; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hydomako, R; Kurchaninov, L; Jonsell, S; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S

    2012-01-01

    Recently, antihydrogen atoms were trapped at CERN in a magnetic minimum (minimum-B) trap formed by superconducting octupole and mirror magnet coils. The trapped antiatoms were detected by rapidly turning off these magnets, thereby eliminating the magnetic minimum and releasing any antiatoms contained in the trap. Once released, these antiatoms quickly hit the trap wall, whereupon the positrons and antiprotons in the antiatoms annihilated. The antiproton annihilations produce easily detected signals; we used these signals to prove that we trapped antihydrogen. However, our technique could be confounded by mirror-trapped antiprotons, which would produce seemingly-identical annihilation signals upon hitting the trap wall. In this paper, we discuss possible sources of mirror-trapped antiprotons and show that antihydrogen and antiprotons can be readily distinguished, often with the aid of applied electric fields, by analyzing the annihilation locations and times. We further discuss the general properties of antipr...

  10. Laser Doppler imaging, thermographic imaging, and tissue oxygen saturation measurements detect early skin reactions during breast radiotherapy

    Science.gov (United States)

    Harrison, David K.; Harrison, Eileen M.; Newton, David J.; Windsor, Phyllis M.

    2001-05-01

    A range of acute skin reactions, ranging from mild erythema to moist desquamation, can be seen in patients receiving standard fractionated radiotherapy to the breast for conservation therapy of breast carcinoma. In a number of cases these reactions can cause considerable discomfort and seriously affect the patient's quality of life. In previous studies we have used the techniques of laser Doppler imaging, digital thermographic imaging and lightguide spectrophotometry to study oxygen supply and blood flow in inflammatory reactions induced experimentally in forearm skin. The present study is an attempt to use the same techniques to investigate whether any or all of them can detect changes in breast skin very early on in the course of radiotherapy treatment. A further aim of the longer term study is to investigate to what extent these early changes may be able to predict the occurrence later of severe acute or delayed reactions.

  11. Design of a High Luminosity 100 TeV Proton Antiproton Collider

    Energy Technology Data Exchange (ETDEWEB)

    Oliveros Tuativa, Sandra Jimena [Univ. of Mississippi, Oxford, MS (United States)

    2017-04-01

    Currently new physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. A 10$^{\\,34}$ cm$^{-2}$ s$^{-1}$ luminosity 100 TeV proton-antiproton collider is explored with 7$\\times$ the energy of the LHC. The dipoles are 4.5\\,T to reduce cost. A proton-antiproton collider is selected as a future machine for several reasons. The cross section for many high mass states is 10 times higher in $p\\bar{p}$ than $pp$ collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the number of events per bunch crossing, because lower beam currents can produce the same rare event rates. Events are also more centrally produced, allowing a more compact detector with less space between quadrupole triplets and a smaller $\\beta^{*}$ for higher luminosity. To adjust to antiproton beam losses (burn rate), a Fermilab-like antiproton source would be adapted to disperse the beam into 12 different momentum channels, using electrostatic septa, to increase antiproton momentum capture 12 times. At Fermilab, antiprotons were stochastically cooled in one Debuncher and one Accumulator ring. Because the stochastic cooling time scales as the number of particles, two options of 12 independent cooling systems are presented. One electron cooling ring might follow the stochastic cooling rings for antiproton stacking. Finally antiprotons in the collider ring would be recycled during runs without leaving the collider ring, by joining them to new bunches with snap bunch coalescence and synchrotron damping. These basic ideas are explored in this work on a future 100 TeV proton-antiproton collider and the main parameters are presented.

  12. Design of a High Luminosity 100 TeV Proton-Antiproton Collider

    Science.gov (United States)

    Oliveros Tautiva, Sandra Jimena

    Currently new physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. A 10 34 cm-2 s-1 luminosity 100 TeV proton-antiproton collider is explored with 7x the energy of the LHC. The dipoles are 4.5 T to reduce cost. A proton-antiproton collider is selected as a future machine for several reasons. The cross section for many high mass states is 10 times higher in pp than pp collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the number of events per bunch crossing, because lower beam currents can produce the same rare event rates. Events are also more centrally produced, allowing a more compact detector with less space between quadrupole triplets and a smaller beta* for higher luminosity. To adjust to antiproton beam losses (burn rate), a Fermilab-like antiproton source would be adapted to disperse the beam into 12 different momentum channels, using electrostatic septa, to increase antiproton momentum capture 12 times. At Fermilab, antiprotons were stochastically cooled in one Debuncher and one Accumulator ring. Because the stochastic cooling time scales as the number of particles, two options of 12 independent cooling systems are presented. One electron cooling ring might follow the stochastic cooling rings for antiproton stacking. Finally antiprotons in the collider ring would be recycled during runs without leaving the collider ring, by joining them to new bunches with snap bunch coalescence and synchrotron damping. These basic ideas are explored in this work on a future 100 TeV proton-antiproton collider and the main parameters are presented.

  13. Proton-Proton and Proton-Antiproton Colliders

    CERN Document Server

    Scandale, Walter

    2014-01-01

    In the last five decades, proton–proton and proton–antiproton colliders have been the most powerful tools for high energy physics investigations. They have also deeply catalyzed innovation in accelerator physics and technology. Among the large number of proposed colliders, only four have really succeeded in becoming operational: the ISR, the SppbarS, the Tevatron and the LHC. Another hadron collider, RHIC, originally conceived for ion–ion collisions, has also been operated part-time with polarized protons. Although a vast literature documenting them is available, this paper is intended to provide a quick synthesis of their main features and key performance.

  14. Antiproton annihilation at rest in nitrogen and deuterium gas

    International Nuclear Information System (INIS)

    Riedlberger, J.; Amsler, C.; Doser, M.; Straumann, U.; Truol, P.; Bailey, D.; Barlag, S.; Gastaldi, U.; Landua, R.; Sabev, C.; Duch, K.D.; Heel, M.; Kalinowsky, H.; Kayser, F.; Klempt, E.; May, B.; Schreiber, O.; Weidenauer, P.; Ziegler, M.; Dahme, W.; Feld-Dahme, F.; Schaefer, U.

    1989-01-01

    Results on antiproton absorption at rest in gaseous nitrogen and deuterium are presented from an analysis of approximately 10 6 events each taken with a magnetic spectrometer. Inclusive features such as pion and proton multiplicities and spectra are presented. Data relating to absorption modes requiring more than one nucleon, such as the Λ yield, the Λ spectrum, and the exclusive deuterium channels bar pd→π - p, ΛK + π - are discussed. The fully reconstructable channels bar pd→π + π - π - p,π + π + π - π - π - p also show a high-energy proton tail unaccounted for by single nucleon rescattering mechanisms

  15. High resolution X-ray spectroscopy in light antiprotonic atoms

    CERN Document Server

    Borchert, G L; Augsburger, M A; Castelli, C M; Chatellard, D; Egger, J P; El-Khoury, P; Elble, M; Gorke, H; Gotta, D; Hauser, P R; Indelicato, P J; Kirch, K; Lenz, S; Nelms, N; Rashid, K; Schult, O W B; Siems, T; Simons, L M

    2000-01-01

    At the LEAR facility, CERN, antiprotonic L alpha transitions in light elements have been investigated with a focussing crystal spectrometer. The high resolution of the experiment allowed for the first time to resolve in pH/pH the 2/sup 3/P/sub 0/ state from the close-lying states 2/sup 3/P/sub 2/, 2/sup 1/P/sub 1/, and 2/sup 3/P /sub 1/. In pD the corresponding transitions were found to be more than an order of magnitude broader. To a large extent the results for pH support the meson exchange model. (15 refs).

  16. Precise and real-time measurement of 3D tumor motion in lung due to breathing and heartbeat, measured during radiotherapy

    International Nuclear Information System (INIS)

    Seppenwoolde, Yvette; Shirato, Hiroki; Kitamura, Kei; Shimizu, Shinichi; Herk, Marcel van; Lebesque, Joos V.; Miyasaka, Kazuo

    2002-01-01

    Purpose: In this work, three-dimensional (3D) motion of lung tumors during radiotherapy in real time was investigated. Understanding the behavior of tumor motion in lung tissue to model tumor movement is necessary for accurate (gated or breath-hold) radiotherapy or CT scanning. Methods: Twenty patients were included in this study. Before treatment, a 2-mm gold marker was implanted in or near the tumor. A real-time tumor tracking system using two fluoroscopy image processor units was installed in the treatment room. The 3D position of the implanted gold marker was determined by using real-time pattern recognition and a calibrated projection geometry. The linear accelerator was triggered to irradiate the tumor only when the gold marker was located within a certain volume. The system provided the coordinates of the gold marker during beam-on and beam-off time in all directions simultaneously, at a sample rate of 30 images per second. The recorded tumor motion was analyzed in terms of the amplitude and curvature of the tumor motion in three directions, the differences in breathing level during treatment, hysteresis (the difference between the inhalation and exhalation trajectory of the tumor), and the amplitude of tumor motion induced by cardiac motion. Results: The average amplitude of the tumor motion was greatest (12±2 mm [SD]) in the cranial-caudal direction for tumors situated in the lower lobes and not attached to rigid structures such as the chest wall or vertebrae. For the lateral and anterior-posterior directions, tumor motion was small both for upper- and lower-lobe tumors (2±1 mm). The time-averaged tumor position was closer to the exhale position, because the tumor spent more time in the exhalation than in the inhalation phase. The tumor motion was modeled as a sinusoidal movement with varying asymmetry. The tumor position in the exhale phase was more stable than the tumor position in the inhale phase during individual treatment fields. However, in many

  17. Elastic scattering of antiprotons on 4He at 600 MeV/c

    International Nuclear Information System (INIS)

    Batusov, Yu.A.; Bunyatov, S.A.; Falomkin, I.V.

    1990-01-01

    The differential cross section for antiproton elastic scattering on 4 He at 607.7 MeV/c momentum is measured. The total elastic cross section σ el =(120.9±2.5) mb and the total p -4 He interaction cross section σ tot =(360.1±5.6) mb are determined. Partial wave analysis reveals that the P,D and F-waves are dominant in the scattering. The angular dependence of differential cross section exhibits the diffraction pattern typical of scattering on a strongly absorbing disk. Simply taking into account diffuseness of the disk provides good agreement of calculations with the experimental data. 17 refs.; 8 figs.; 1 tab

  18. Exclusive production of proton-antiproton pairs in photon-photon collisions

    International Nuclear Information System (INIS)

    Bartel, W.; Becker, L.; Cords, D.; Felst, R.; Haidt, D.; Knies, G.; Krehbiel, H.; Laurikainen, P.; Magnussen, N.; Meinke, R.; Naroska, B.; Olsson, J.; Schmidt, D.; Steffen, P.; Dietrich, G.; Hagemann, J.; Heinzelmann, G.; Kado, H.; Kawagoe, K.; Kleinwort, C.; Kuhlen, M.; Petersen, A.; Ramcke, R.; Schneekloth, U.; Weber, G.; Allison, J.; Ball, A.H.; Barlow, R.J.; Chrin, J.; Duerdoth, I.P.; Greenshaw, T.; Loebinger, F.K.; Macbeth, A.A.; Mills, H.E.; Murphy, P.G.; Stephens, K.; Warming, P.; Glasser, R.G.; Hill, P.; Skard, J.A.J.; Wagner, S.R.; Zorn, G.T.; Cartwright, S.L.; Clarke, D.; Marshall, R.; Middleton, R.P.; Kawamoto, T.; Kobayashi, T.; Takeda, H.; Takeshita, T.; Yamada, S.

    1986-01-01

    Total and differential cross sections for exclusive production of proton-antiproton pairs in photon-photon collisions have been measured using the JADE detector at PETRA. The total cross section in the CM angular range vertical strokecos thetasup(*)vertical stroke<0.6 reaches a maximum value of 3.8 nb for a γγ invariant mass of Wsub(γγ) = 2.25 GeV, and decreases rapidly for higher values of Wsub(γγ). In the range 2.0 GeV < Wsub(γγ) < 2.6 GeV the angular distribution is not isotropic. The nucleons are preferentially emitted at large angles to the collision axis. (orig.)

  19. Bottom quark anti-quark production and mixing in proton anti-proton collisions

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhaoou [Yale Univ., New Haven, CT (United States)

    2003-03-01

    The studies of bottom quark-antiquark production in proton-antiproton collisions play an important role in testing perturbative QCD. Measuring the mixing parameter of B mesons imposes constraints on the quark mixing (CKM) matrix and enhances the understanding of the Standard Model. Multi-GeV p$\\bar{p}$ colliders produce a significant amount of b$\\bar{b}$ pairs and thus enable studies in both of these fields. This thesis presents results of the b$\\bar{b}$ production cross section from p$\\bar{p}$ collisions at √s = 1.8 TeV and the time-integrated average B$\\bar{B}$ mixing parameter ($\\bar{χ}$) using highmass dimuon d a ta collected by CDF during its Run IB.

  20. Decay of Hot Nuclei at Low Spins Produced by Antiproton-Annihilation in Heavy Nuclei

    CERN Multimedia

    2002-01-01

    % PS208 \\\\ \\\\ The objective of the experiment is to study (i) the thermal excitation energy distribution of antiproton-induced reactions in heavy nuclei and (ii) the decay properties of hot nuclei at low spins via evaporation, multifragmentation and fission as a function of excitation energy. The experimental set-up consists of 4-$\\pi$ detectors: the Berlin Neutron Ball~(BNB) which is a spherical shell of gadolinium-loaded scintillator liquid with an inner and outer diameter of 40 and 160~cm, respectively. This detector counts the number of evaporated neutrons in each reaction. Inside BNB there is a 4-$\\pi$ silicon ball~(BSIB) with a diameter of 20~cm consisting of 162 detectors which measure energy and multiplicity of all emitted charged nuclear particles. The particles are identified via time of flight, energy and pulse shape correlations.

  1. CERN: LEP delivers; Looking deeper at spin; Handling low energy antiprotons

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    One year ago, with the world catalogue of Z particles - the electrically neutral carrier of the weak nuclear force - containing a few hundred examples, it sounded extravagant when proponents of CERN's new LEP electron-positron collider promised a hundred thousand Zs by Christmas 1989. The first round of experiments in the North Area of CERN's SPS proton synchrotron included a considerable investment in studies using high energy muon beams. This paid off with important contribuions to physics, particularly in the measurement of the quark/gluon content (structure functions) of nucleons. ; The LEAR low energy antiproton ring at CERN takes its antimatter beams down to very low kinetic energies - less than 10 MeV - for a unique range of physics studies. However even these modest energies are too high for a series of experiments aiming to explore the effects of gravity on antimatter

  2. Theoretical motivation for gravitation experiments on ultra-low energy antiprotons and antihydrogen

    International Nuclear Information System (INIS)

    Nieto, M.M.

    1995-01-01

    It is known that the generally accepted theories of gravity and quantum mechanics are fundamentally incompatible. Thus, when one tries to combine these theories, one must beware of physical pitfalls. Modern theories of quantum gravity are trying to overcome these problems. Any ideas must confront the present agreement with general relativity, but yet be free to wonder about not understood phenomena, such as the dark matter problem. This all has led some open-quotes intrepidclose quotes theorists to consider a new gravitational regime, that of antimatter. Even more open-quotes daringclose quotes experimentalists are attempting, or considering attempting, the measurement of the gravitational force on antimatter, including low-energy antiprotons and, perhaps most enticing, antihydrogen

  3. Self-polarization of stored (anti-)protons: Status of the Spin-Splitter experiment at IUCF

    International Nuclear Information System (INIS)

    Rossmanith, R.

    1990-01-01

    Several years ago a selfpolarization effect for stored (anti-)protons and ions was investigated theoretically. The effect is based on the well-known Stern-Gerlach effect in gradient fields. The aim of the ongoing measurements at IUCF is to verify experimentally the various assumptions on which this effect is based. The final goal is to demonstrate this new polarization effect. The proposed effect could be a powerful tool to produce polarized stored hadron beams both in the low energy range and at SSC and LHC energies

  4. The W boson transverse momentum spectrum in proton-antiproton collisions at radical s = 1. 8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Winer, B.L.

    1991-02-01

    The Collider Detector at Fermilab (CDF) was used to measure the transverse momentum distribution of W boson produced in proton-antiproton collisions at the Tevatron collider. The W bosons were identified by the decay W {yields} e{nu}. The results are in good agreement with a next-to-leading order calculation. The cross section for W production with P{sub T} > 50 GeV/c is 423 {plus minus} 58 (stat.) {plus minus} 108 (sys.) pb. 58 refs., 53 figs., 16 tabs.

  5. The International Facility for Antiproton and Ion Research FAIR

    International Nuclear Information System (INIS)

    Gutbrod, H. H.

    2008-01-01

    The proposed project FAIR (Facility for Antiproton and Ion Research) is an international accelerator facility of the next generation and will be built as a new company FAIR GmbH next to the site of GSI. About 15 countries have expressed their intention to become shareholders. FAIR builds on the experience and technological developments already made at the existing GSI facility, and at the FAIR partner institutes world wide and incorporates new technological concepts. At its heart is a double ring facility with a circumference of 1100 meters. A system of cooler-storage rings for effective beam cooling at high energies and various experimental halls will be connected to the facility. The existing GSI accelerators - together with the planned proton-linac - serve as injector for the new facility. The double-ring synchrotron will provide ion beams of unprecedented intensities as well as of considerably increased energy. Thereby intense beams of secondary beams - unstable nuclei or antiprotons - can be produced. The system of storage-cooler rings allows the quality of these secondary beams - their energy spread and emittance - to be drastically improved. Moreover, in connection with the double ring synchrotron, an efficient parallel operation of up to four scientific programs can be realized at a time. The project is based on many technological innovations, the most important of which are five beam properties: Highest Beam Intensities, Brilliant Beam Quality, Higher Beam Energies, Highest Beam Power, Parallel Operation

  6. Energy dependence of proton-proton and antiproton-proton scattering at the CERN intersecting storage rings

    International Nuclear Information System (INIS)

    Botje, M.A.J.

    1984-01-01

    This thesis describes measurements of proton-proton and proton-antiproton elastic scattering with the scattered particles emerging at small angles in the centre of mass (CM) system. These measurements have been performed at the CERN Intersecting Storage Rings (ISR). The direct comparison of pp and anti pp scattering in this energy range is of considerable interest. This is because measurements on pp scattering alone, have revealed that in the ISR energy range both elastic- and total pp cross-sections increase with increasing energy. It is the subject of this thesis to check the prediction that the proton-antiproton cross section will do the same. The present experiment measures the angular distribution of pp and anti pp elastic scattering at small angles (typically 1-10 mrad) and at different energies. From these measurements a comparison of the energy behaviour of the pp and anti pp forward nuclear scattering amplitudes is obtained. This behaviour can be described in terms of three parameters: the total cross-section, the ratio of the real-to-imaginary part of the forward nuclear amplitude and a parameter, the slope, characterising the dependence of the process on the squared four-momentum transfer between the incident and the scattered particle. (Auth.)

  7. Search for charm in pion and anti-proton interactions near threshold

    International Nuclear Information System (INIS)

    Kadel, R.W.

    1977-08-01

    A search is reported for charmed particles produced by antiprotons of momentum 15.0, 12.4, and 8.5 GeV/c and pions of momentum 15.0 and 10.5 GeV/c. Charged particles emerging from a carbon target near 90 0 in the center of mass (18 0 lab) were detected in a double arm spectrometer with a low momentum cutoff of P/sub lab/ greater than or equal to 1 GeV/c. The best upper limit is the process anti PN → D 0 ( anti D 0 ) + X, where the D 0 (anti D 0 ) decays into K - - π + (K + - π - ), is: sigmaB = 780 +- 300 nb at a beam momentum of 8.5 GeV/c. For the 10.5 GeV/c pion running the trigger was restricted by requiring the presence of a slow forward pion in a third spectrometer area, in coincidence with the usual double arm trigger. The acceptance of the third arm was chosen to include pions from the decay of the charmed D* - meson, which has a very small Q value. The upper limit for the process: π - N → D* - + X, D* - → π - + anti D 0 , anti D 0 → K + + π - is sigmaB = 16 +- 16 nb. Additionally, a measurement of inclusive K* (1421) production in anti-proton interactions at 8.5 GeV/c is reported. The cross-section times branching ratio is: sigma(anti PN → K*(1421) + X)*B/sub K*→Kπ/ = 4. +- .8 x 10 -29 cm 2

  8. Efficient accumulation of antiprotons and positrons, production of slow mono-energetic beams, and their applications

    CERN Document Server

    Yamazaki, Yasunori

    2004-01-01

    Recent progress of ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) project, particularly the antiproton trapping and slow antiproton production, is discussed. An RFQD (Radio Frequency Quadrupole Decelerator) installed in the ASACUSA beam line has an excellent deceleration efficiency of 25% providing 10-130keV antiprotons, which improves the final accumulation efficiency at least one and half orders of magnitude. The decelerated antiprotons are then injected in a large volume multiring trap, stored, and electron-cooled. About 1 million antiprotons are successfully accumulated per one AD shot and 10-500eV antiprotons are extracted as a mono-energetic beam. A UHV compatible positron accumulation is newly developed combining electron plasma and an ion cloud, which yields an accumulation rate as high as 400e **+s/mCi, two and a half orders of magnitude higher than other UHV compatible schemes. A new scheme to synthesize a spin-polarized antihydrogen beam is also discussed, which will play a vit...

  9. Palliative Radiotherapy

    International Nuclear Information System (INIS)

    Salinas, J.

    2003-01-01

    Palliative care does not attempt to prolong survival but to the achieve the highest quality of life both for the patient and their family covering their physical, psychological, social and spiritual needs. Radiotherapy (RT), one of the most important therapeutic modalities, has a great significance in palliative medicine for cancer since it attempts to reduce as much as possible the acute reaction associated with the treatment for the patient. (Author)

  10. The antiproton-hydrogen atom interaction

    International Nuclear Information System (INIS)

    Morgan, D.L. Jr.

    1994-07-01

    The bar p-H interaction is the most important aspect of the bar ppe system. While this interaction is worthy of study in itself, it is also relevant to a number of bar p applications, both practical and in the area of fundamental physics. Theoretical study of p-H commenced more than 20 years ago and has continued with growing interest through the present. Experimental study has been limited, but recently measurements have been made of bar p's slowing in hydrogen at KeV energies, which shed light on their interaction with hydrogen atoms. Theoretical work involving various kinds and levels of approximation has now been carried out for a variety of bar p energy domains. Particular attention has been given to bar p capture at low and sub eV energies, in which a bound bar p-p state is formed, and to H excitation and ionization at KeV energies. Such calculations now extend into the sub Kelvin domain of energies. It is beginning to be possible to make comparisons between experiment and calculation and to compare calculations to one another. These comparisons suggest that theoretical work needs to be carried out in some intermediate energy domains and that some past calculations have to be repeated with more accurate methods

  11. Quality assurance in radiotherapy

    International Nuclear Information System (INIS)

    2003-03-01

    Good radiotherapy results and safety of treatment require the radiation to be optimally applied to a specified target area and the correct dose. According to international recommendations, the average uncertainty in therapeutic dose should not exceed 5%. The need for high precision in therapeutic dose requires quality assurance covering the entire radiotherapy process. Besides the physical and technical characteristics of the therapy equipment, quality assurance must include all radiotherapy equipment and procedures that are significant for the correct magnitude and precision of application of the therapeutic dose. The duties and responsibilities pertaining to various stages of treatment must also be precisely defined. These requirements may be best implemented through a quality system. The general requirements for supervision and quality assurance of medical radiation apparatus are prescribed in section 40 of the Radiation Act (592/1991, amendment 1142/1998) and in sections 18 and 32 of the Decree of the Ministry of Social Affairs and Health on the medical use of radiation (423/2000). Guide ST 2.2 imposes requirements on structural radiation shielding of radiotherapy equipment and the premises in which it is used, and on warning and safety arrangements. Guide ST 1.1 sets out the general safety principles for radiation practices and regulatory control procedure for the use of radiation. Guide ST 1.6 provides general requirements for operational measures in the use of radiation. This Guide sets out the duties of responsible parties (the party running a radiation practice) in respect of arranging and maintaining radiotherapy quality assurance. The principles set out in this Guide and Guide ST 6.3 may be applied to radionuclide therapy

  12. Psychosocial effects of radiotherapy after mastectomy

    International Nuclear Information System (INIS)

    Hughson, A.V.M.; Cooper, A.F.; Smith, D.C.; McArdle, C.S.

    1987-01-01

    Psychosocial morbidity was measured in 47 patients who received postoperative radiotherapy and in 38 who received no further treatment after mastectomy. Roughly one third of all patients experienced depression or anxiety. One month after operation, before radiotherapy, there were no significant differences between the two groups in any of the measures of psychosocial morbidity. Knowledge of impending treatment did not seem to influence morbidity. At three months patients who had completed radiotherapy had significantly more somatic symptoms and social dysfunction than those not so treated. At six months the radiotherapy group continued to show more somatic symptoms, but a year after operation there were no significant differences between the groups. Although several patients who received radiotherapy were upset by their treatment, the study failed to confirm that depression and anxiety were commoner among those given radiotherapy than among patients given no further treatment. (author)

  13. Review of the High Performance Antiproton Trap (HiPAT) Experiment at the Marshall Space Flight Center

    Science.gov (United States)

    Pearson, J. B.; Sims, Herb; Martin, James; Chakrabarti, Suman; Lewis, Raymond; Fant, Wallace

    2003-01-01

    The significant energy density of matter-antimatter annihilation is attractive to the designers of future space propulsion systems, with the potential to offer a highly compact source of power. Many propulsion concepts exist that could take advantage of matter-antimatter reactions, and current antiproton production rates are sufficient to support basic proof-of-principle evaluation of technology associated with antimatter- derived propulsion. One enabling technology for such experiments is portable storage of low energy antiprotons, allowing antiprotons to be trapped, stored, and transported for use at an experimental facility. To address this need, the Marshall Space Flight Center's Propulsion Research Center is developing a storage system referred to as the High Performance Antiproton Trap (HiPAT) with a design goal of containing 10(exp 12) particles for up to 18 days. The HiPAT makes use of an electromagnetic system (Penning- Malmberg design) consisting of a 4 Telsa superconductor, high voltage electrode structure, radio frequency (RF) network, and ultra high vacuum system. To evaluate the system normal matter sources (both electron guns and ion sources) are used to generate charged particles. The electron beams ionize gas within the trapping region producing ions in situ, whereas the ion sources produce the particles external to the trapping region and required dynamic capture. A wide range of experiments has been performed examining factors such as ion storage lifetimes, effect of RF energy on storage lifetime, and ability to routinely perform dynamic ion capture. Current efforts have been focused on improving the FW rotating wall system to permit longer storage times and non-destructive diagnostics of stored ions. Typical particle detection is performed by extracting trapped ions from HiPAT and destructively colliding them with a micro-channel plate detector (providing number and energy information). This improved RF system has been used to detect various

  14. Accuracy of volume measurement using 3D ultrasound and development of CT-3D US image fusion algorithm for prostate cancer radiotherapy

    International Nuclear Information System (INIS)

    Baek, Jihye; Huh, Jangyoung; Hyun An, So; Oh, Yoonjin; Kim, Myungsoo; Kim, DongYoung; Chung, Kwangzoo; Cho, Sungho; Lee, Rena

    2013-01-01

    Purpose: To evaluate the accuracy of measuring volumes using three-dimensional ultrasound (3D US), and to verify the feasibility of the replacement of CT-MR fusion images with CT-3D US in radiotherapy treatment planning. Methods: Phantoms, consisting of water, contrast agent, and agarose, were manufactured. The volume was measured using 3D US, CT, and MR devices. A CT-3D US and MR-3D US image fusion software was developed using the Insight Toolkit library in order to acquire three-dimensional fusion images. The quality of the image fusion was evaluated using metric value and fusion images. Results: Volume measurement, using 3D US, shows a 2.8 ± 1.5% error, 4.4 ± 3.0% error for CT, and 3.1 ± 2.0% error for MR. The results imply that volume measurement using the 3D US devices has a similar accuracy level to that of CT and MR. Three-dimensional image fusion of CT-3D US and MR-3D US was successfully performed using phantom images. Moreover, MR-3D US image fusion was performed using human bladder images. Conclusions: 3D US could be used in the volume measurement of human bladders and prostates. CT-3D US image fusion could be used in monitoring the target position in each fraction of external beam radiation therapy. Moreover, the feasibility of replacing the CT-MR image fusion to the CT-3D US in radiotherapy treatment planning was verified.

  15. Rehabilitation in radiotherapy of osteosarcomas in children and adolescents

    International Nuclear Information System (INIS)

    Bizer, V.A.

    1985-01-01

    Rehabilitation in radiotherapy of osteosarcomas in children and adolescents is manifested in rational planning of radiotherapy and in simplest orthopedic measures carried out simultaneously with irradiation and aimed at removal of contractures in limb joints

  16. An investigation of anxiety about radiotherapy deploying the radiotherapy categorical anxiety scale

    International Nuclear Information System (INIS)

    Shimotsu, Sakie; Karasawa, Kumiko; Ito, Kana; Saito, Anneyuko I.; Izawa, Hiromi; Kawase, Eri; Horikawa, Naoshi

    2010-01-01

    Radiotherapy is one of the major methods for treating cancer, but many patients undergoing radiotherapy have deep concerns about receiving radiation treatment. This problem is not generally appreciated and has not been adequately studied. The objective of this investigation was to empirically investigate the anxieties that cancer patients feel towards radiotherapy by using questionnaires to classify and quantitatively measure their concerns. A preliminary interview to develop a questionnaire was carried out with 48 patients receiving radiotherapy to discover their anxieties about on-going treatments. Subsequently, a main study was performed using a questionnaire with 185 patients to classify their types of anxiety and to ascertain the reliability and validity of the responses. Confirmatory factor analysis was then carried out with a 17-item Radiotherapy Categorical Anxiety Scale. Three anxiety factors were abstracted by factor analysis: adverse effects of radiotherapy, environment of radiotherapy, and treatment effects of radiotherapy. Reliability, content validity, and concurrent validity were obtained. The adequacy of the three-factor model of anxiety concerning radiotherapy was confirmed. A 17-item Radiotherapy Categorical Anxiety Scale was formulated to quantitatively measure the specific types of anxiety among cancer patients receiving radiotherapy. (author)

  17. FPGA-Based Instrumentation for the Fermilab Antiproton Source

    CERN Document Server

    Ashmanskas, Bill; Kiper, Terry; Peterson, David

    2005-01-01

    We have designed and built low-cost, low-power, ethernet-based circuit boards to apply DSP techniques to several instrumentation upgrades in the Fermilab Antiproton Source. Commodity integrated circuits such as direct digital synthesizers, D/A and A/D converters, and quadrature demodulators enable digital manipulation of RF waveforms. A low cost FPGA implements a variety of signal processing algorithms in a manner that is easily adapted to new applications. An embedded microcontroller provides FPGA configuration, control of data acquisition, and command-line interface. A small commercial daughter board provides an ethernet-based TCP/IP interface between the microcontroller and the Fermilab accelerator control network. The board is packaged as a standard NIM module. Applications include Low Level RF control for the Debuncher, readout of transfer-line Beam Position Monitors, and narrow-band spectral analysis of diagnostic signals from Schottky pickups.

  18. Proton-Antiproton Annihilation into Neutral Strange Mesons

    Science.gov (United States)

    Ritter, J.; Bertolotto, L.; Buzzo, A.; Debevec, P.; Drijard, D.; Easo, S.; Eisenstein, R. A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Fischer, H.; Franz, J.; Geyer, R.; Hamann, N. H.; Harris, P. G.; Hertzog, D. W.; Hughes, S. A.; Johansson, A.; Johansson, T.; Jones, R. T.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Macri, M.; Marinelli, M.; Moosburger, M.; Mouëllic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J.-M.; Pia, M. G.; Pomp, S.; Price, M.; Reimer, P. E.; Ritter, J.; Robutti, E.; Röhrich, K.; Rook, M.; Sefzick, T.; Rössle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tayloe, R.; Tscheulin, M.; Urban, H. J.; Wirth, H.; Zipse, H.; Jetset (Ps202) Collaboration:

    1997-06-01

    In a search for gluonic hadrons, the formation channels p¯p → K sK s, p¯p → ηη, p¯p → π 0η and p¯p → π 0π 0 were studied in the mass range from 2.1 to 2.4 GeV using the Jetset (PS202) detector and an internal molecular hydrogen cluster jet target installed in the Low Energy Antiproton Ring (LEAR) at CERN. Cross sections for p¯p → K sK s have been obtained and limits are set on the non-observation of the ξ(2230). Conversely, we find evidence for a narrow signal in a preliminary analysis of our p¯p → ηη data consistent with a narrow ξ(2230).

  19. Proton-antiproton annihilation into neutral strange mesons

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, J. [Illinois Univ., Urbana (United States). Loomis Lab.; Bertolotto, L.; Buzzo, A.; Debevec, P.; Drijard, D.; Easo, S.; Eisenstein, R.A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Fischer, H.; Franz, J.; Geyer, R.; Hamann, N.H.; Harris, P.G.; Hertzog, D.W.; Hughes, S.A.; Johansson, A.; Johansson, T.; Jones, R.T.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Macri, M.; Marinelli, M.; Moosburger, M.; Mouellic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J.-M.; Pia, M.G.; Pomp, S.; Price, M.; Reimer, P.E.; Robutti, E.; Roehrich, K.; Rook, M.; Sefzick, T.; Roessle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tayloe, R.; Tscheulin, M.; Urban, H.J.; Wirth, H.; Zipse, H.; JETSET Collaboration

    1997-06-01

    In a search for gluonic hadrons, the formation channels pp{yields}K{sub S}K{sub S}, pp{yields}{eta}{eta}, pp{yields}{pi}{sup 0}{eta} and pp{yields}{pi}{sup 0}{pi}{sup 0} were studied in the mass range from 2.1 to 2.4 GeV using the Jetset (PS202) detector and an internal molecular hydrogen cluster jet target installed in the Low Energy Antiproton Ring (LEAR) at CERN. Cross sections for pp{yields}K{sub S}K{sub S} have been obtained and limits are set on the non-observation of the {xi}(2230). Conversely, we find evidence for a narrow signal in a preliminary analysis of our pp{yields}{eta}{eta} d ata consistent with a narrow {xi}(2230). (orig.).

  20. Proton-antiproton annihilation into neutral strange mesons

    International Nuclear Information System (INIS)

    Ritter, J.; Bertolotto, L.; Buzzo, A.; Debevec, P.; Drijard, D.; Easo, S.; Eisenstein, R.A.; Evangelista, C.; Eyrich, W.; Fearnley, T.; Ferro-Luzzi, M.; Fischer, H.; Franz, J.; Geyer, R.; Hamann, N.H.; Harris, P.G.; Hertzog, D.W.; Hughes, S.A.; Johansson, A.; Johansson, T.; Jones, R.T.; Kilian, K.; Kirsebom, K.; Klett, A.; Korsmo, H.; Lo Vetere, M.; Macri, M.; Marinelli, M.; Moosburger, M.; Mouellic, B.; Oelert, W.; Ohlsson, S.; Palano, A.; Passaggio, S.; Perreau, J.-M.; Pia, M.G.; Pomp, S.; Price, M.; Reimer, P.E.; Robutti, E.; Roehrich, K.; Rook, M.; Sefzick, T.; Roessle, E.; Santroni, A.; Schmitt, H.; Steinkamp, O.; Stinzing, F.; Stugu, B.; Tayloe, R.; Tscheulin, M.; Urban, H.J.; Wirth, H.; Zipse, H.

    1997-01-01

    In a search for gluonic hadrons, the formation channels pp→K S K S , pp→ηη, pp→π 0 η and pp→π 0 π 0 were studied in the mass range from 2.1 to 2.4 GeV using the Jetset (PS202) detector and an internal molecular hydrogen cluster jet target installed in the Low Energy Antiproton Ring (LEAR) at CERN. Cross sections for pp→K S K S have been obtained and limits are set on the non-observation of the ξ(2230). Conversely, we find evidence for a narrow signal in a preliminary analysis of our pp→ηη d ata consistent with a narrow ξ(2230). (orig.)

  1. Survey and alignment of the Fermilab recycler antiproton storage ring

    International Nuclear Information System (INIS)

    Arics, Babatunde O.O.

    1999-01-01

    In June of 1999 Fermilab commissioned a newly constructed antiproton storage ring, the 'Recycler Ring', in the Main Injector tunnel directly above the Main Injector beamline. The Recycler Ring is a fixed 8 GeV kinetic energy storage ring and is constructed of strontium ferrite permanent magnets. The 3319.4-meter-circumference Recycler Ring consists of 344 gradient magnets and 100 quadrupoles all of which are permanent magnets. This paper discusses the methods employed to survey and align these permanent magnets within the Recycler Ring with the specified accuracy. The Laser Tracker was the major instrument used for the final magnet alignment. The magnets were aligned along the Recycler Ring with a relative accuracy of ±0.25 mm. (author)

  2. Pulsed septum magnet for the Fermilab antiproton source

    International Nuclear Information System (INIS)

    Satti, J.A.; Holmes, S.D.

    1985-06-01

    A 2 meter curved pulsed septum magnet for use in the Fermilab Antiproton Source is described. The magnet produces a peak field of 6 kGauss at a current of 20,000 Amperes within a 0.4 msec long pulse. The field uniformity obtained is ΔB/B<0.2% out to 3.8 cm from the copper septum. Power enters the magnet from the center resulting in very simple ends and the magnet incorporates at 0.5 cm steel guard which reduces the field to <1.4 Gauss in the zero-field region. The total septum thickness is 1.3 cm. The vacuum enclosure doubles as the stacking fixture for the magnet laminations allowing easy assembly of a magnet with a 50 m radius of curvature

  3. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  4. Slowing down of 100 keV antiprotons in Al foils

    Science.gov (United States)

    Nordlund, K.

    2018-03-01

    Using energy degrading foils to slow down antiprotons is of interest for producing antihydrogen atoms. I consider here the slowing down of 100 keV antiprotons, that will be produced in the ELENA storage ring under construction at CERN, to energies below 10 keV. At these low energies, they are suitable for efficient antihydrogen production. I simulate the antihydrogen motion and slowing down in Al foils using a recently developed molecular dynamics approach. The results show that the optimal Al foil thickness for slowing down the antiprotons to below 5 keV is 910 nm, and to below 10 keV is 840 nm. Also the lateral spreading of the transmitted antiprotons is reported and the uncertainties discussed.

  5. Extra Low Energy Antiproton ring ELENA : from the conception to the implementation phase

    CERN Document Server

    Bartmann, W; Breuker, H; Butin, F; Carli, C; Eriksson, T; Maury, S; Pasinelli, S; Tranquille, G; Oelert, W

    2014-01-01

    The Extra Low Energy Antiproton ring (ELENA) is a CERN project aiming at constructing a small 30 m circumference synchrotron to further decelerate antiprotons from the Antiproton Decelerator AD from 5.3 MeV to 100 keV. Controlled deceleration in a synchrotron equipped with an electron cooler to reduce emittances in all three planes will allow the existing AD experiments to increase substantially their antiproton capture efficiencies and render new experiments possible. The ELENA design is now well advanced and the project is moving to the implementation phase. Component design and construction are taking place at present for installation foreseen during the second half of 2015 and beginning of 2016 followed by ring commissioning until the end of 2016. New electrostatic transfer lines to the experiments will be installed and commissioned during the first half of 2017 followed by the first physics operation with ELENA. Basic limitations like Intra Beam Scattering limiting the emittances obtained under electron ...

  6. Comprehensive Study for an Optimized Redesign of the CERN's Antiproton Decelerator Target

    CERN Document Server

    AUTHOR|(CDS)2089345; Perillo-Marcone, Antonio; Muñoz-Cobo, Jose-Luis

    2018-04-16

    The Antiproton Decelerator Target (AD-Target) is a unique device responsible for the production of antiprotons at the European Organization for Nuclear Research (CERN). During operation, intense 26 GeV energy proton beams are impacted into its core, made of a 3 mm diameter rod of a high density material such as iridium, creating secondary particles -including antiprotons- from the nuclear reactions induced in its interior. This thesis delves into the characteristics of antiproton production and in particular in the mechanical response of the target core material, which is exposed to a rise of temperature of approximate 2000 degrees Celsius in less than 0.5 microseconds each time is impacted by the primary proton beam. A coupled numerical-experimental approach has been applied for this purpose. Specific computational tools, called hydrocodes, have been used for simulating the extreme dynamic response taking place in the target core and its containing graphite matrix, indicating their potential damage and frag...

  7. Search for TeV-Antiprotons in Space from the Shadowing of Cosmic Rays by the Moon with the L3+C Detector

    CERN Document Server

    Xu, Yupeng

    2005-01-01

    A search for antiprotons in the primary cosmic ray flux has been performed by observing the Moon shadow with the muon data collected by the L3+C experiment at CERN during 1999 and 2000. The angular resolution of the detector and its dependences on the muon energy and zenith angle are obtained at the event level with a Monte Carlo simulation and the analysis of real double muon data using a maximum likelihood method. The Moon shadow effect is observed in three muon momentum bands > 100GeV/c, 65 - 100 GeV/c and 30 - 65 GeV/c with a significance of 7.0 cr, 5.8 cr and 5.2 cr respectively. Two dimensional maximum likelihood analyses are performed, both with binned data and unbinned data. The unbinned method gives a smaller uncertainty on the measurement of the antiproton to proton ratio. For a muon momentum cut at 70 GeV/c, the antiproton to proton ratio is measured to be -0.12 + 0.11 and an upper limit of this ratio is estimated to be 0.08 (at 90% confidence level) for primary energies in the range 0.8 TeV to 2.4...

  8. The influence of breathing motion on intensity modulated radiotherapy in the step-and-shoot technique: phantom measurements for irradiation of superficial target volumes

    Energy Technology Data Exchange (ETDEWEB)

    Thilmann, Christoph [Klinische Kooperationseinheit Radioonkologie des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Haering, Peter [Medizinische Physik des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Thilmann, Lennart [Klinische Kooperationseinheit Radioonkologie des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Unkelbach, Jan [Medizinische Physik des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Rhein, Bernhard [Medizinische Physik des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Nill, Simeon [Medizinische Physik des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Huber, Peter [Klinische Kooperationseinheit Radioonkologie des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Janisch, Elisabeth [Medizinische Physik des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Thieke, Christian [Klinische Kooperationseinheit Radioonkologie des Deutschen Krebsforschungszentrums, INF 280, 69120 Heidelberg (Germany); Debus, Juergen [Klinische Radiologie des Universitaetsklinikums Heidelberg, INF 400, 69120 Heidelberg (Germany)

    2006-03-21

    For intensity modulated radiotherapy (IMRT) of deep-seated tumours, dosimetric variations of the original static dose profiles due to breathing motion can be primarily considered as blurring effects known from conventional radiotherapy. The purpose of this dosimetric study was to clarify whether these results are transferable to superficial targets and to quantify the additional effect of fractionation. A solid polystyrene phantom and an anthropomorphic phantom were used for film and ion chamber dose measurements. The phantoms were installed on an electric driven device and moved with a frequency of 6 or 12 cycles per minute and an amplitude of 4 mm or 10 mm. A split beam geometry of two adjacent asymmetric fields and an IMRT treatment plan with 12 fields for irradiation of the breast were investigated. For the split beam geometry the dose modifications due to unintended superposition of partial fields were reduced by fractionation and completely smoothed out after 20 fractions. IMRT applied to the moving phantom led to a more homogeneous dose distribution compared to the static phantom. The standard deviation of the target dose which is a measure of the dose homogeneity was 10.3 cGy for the static phantom and 7.7 cGy for a 10 mm amplitude. The absolute dose values, measured with ionization chambers, remained unaffected. Irradiation of superficial targets by IMRT in the step-and-shoot technique did not result in unexpected dose perturbations due to breathing motion. We conclude that regular breathing motion does not jeopardize IMRT of superficial target volumes. (note)

  9. Association between measures of treatment quality and disease progression in prostate cancer radiotherapy: An exploratory analysis from the TROG 03.04 RADAR trial.

    Science.gov (United States)

    Marcello, Marco; Ebert, Martin A; Haworth, Annette; Steigler, Allison; Kennedy, Angel; Bulsara, Max; Kearvell, Rachel; Joseph, David J; Denham, James W

    2018-04-01

    Quality assurance methods are incorporated into multicentre radiotherapy clinical trials for ensuring consistent application of trial protocol and quantifying treatment uncertainties. The study's purpose was to determine whether post-treatment disease progression is associated with measures of the quality of radiotherapy treatment. The TROG 03.04 RADAR trial tested the impact of androgen deprivation on prostate cancer patients receiving dose-escalated external beam radiation therapy. The trial incorporated a plan-review process and Level III dosimetric intercomparison at each centre, from which variables suggestive of treatment quality were collected. Kaplan-Meier statistics and Fine and Gray competing risk modelling were employed to test for associations between quality-related variables and the participant outcome local composite progression. Increased 'dose-difference' at the prostatic apex and at the anterior rectal wall, between planned and measured dose, was associated with reduced progression. Participants whose treatment plans included clinical target volume (CTV) to planning target volume (PTV) margins exceeding protocol requirements also experienced reduced progression. Other quality-related variables, including total accrual from participating centres, measures of target coverage and other variations from protocol, were not significantly associated with progression. This analysis has revealed the association of several treatment quality factors with disease progression. Increased dose and dose margin coverage in the prostate region can reduce disease progression. Extensive and rigorous monitoring has helped to maximise treatment quality, reducing the incidence of quality-indicator outliers, and thus reduce the chance of observing significant associations with progression rates. © 2017 The Royal Australian and New Zealand College of Radiologists.

  10. On the Utility of Antiprotons as Drivers for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, L J; Orth, C D; Tabak, M

    2003-10-20

    By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton beam required to penetrate to the desired annihilation point is always small relative to the deposited annihilation energy. We show that heavy metal seeding of the fuel and/or ablator is required to optimize local deposition of annihilation energy and determine that a minimum of {approx}3x10{sup 15} injected antiprotons will be required to achieve high yield (several hundred megajoules) in any target configuration. Target gains - i.e., fusion yields divided by the available p - {bar p} annihilation energy from the injected antiprotons (1.88GeV/{bar p}) - range from {approx}3 for volumetric ignition targets to {approx}600 for fast ignition targets. Antiproton-driven ICF is a speculative concept, and the handling of antiprotons and their required injection precision - temporally and spatially - will present significant technical challenges. The storage and manipulation of low-energy antiprotons, particularly in the form of antihydrogen, is a science in its infancy and a large scale-up of antiproton production over present supply

  11. Radiation Pneumonitis after Radiotherapy of Neck Lymphoma

    Directory of Open Access Journals (Sweden)

    Min Wei

    2014-01-01

    Full Text Available Radiotherapy is still one of the effective means for treatment of malignant tumors up to now. Particularly, it is an indispensable effective measure for treatment of some lymphoma patients. In routine work, radiation pneumonitis (RP is the most significant complication of acute treatment-related toxicities in lung cancer; however, serious radioactive pneumonia is rare for the radiotherapy of neck lymphoma because the volume of the lungs affected by radiation dose was very small. We report a lymphoma case, where the patient had undergone radiotherapy for the bilateral neck and bilateral supraclavicular/infraclavicular area. Following completion of radiotherapy, the patient developed severe radiation pneumonitis.

  12. Radiation pneumonitis after radiotherapy of neck lymphoma.

    Science.gov (United States)

    Wei, Min; Cai, Jun; Tong, Tao; Yu, Shihua; Yang, Yonghua; Zhang, Weijia; Yang, Jiyuan

    2014-01-01

    Radiotherapy is still one of the effective means for treatment of malignant tumors up to now. Particularly, it is an indispensable effective measure for treatment of some lymphoma patients. In routine work, radiation pneumonitis (RP) is the most significant complication of acute treatment-related toxicities in lung cancer; however, serious radioactive pneumonia is rare for the radiotherapy of neck lymphoma because the volume of the lungs affected by radiation dose was very small. We report a lymphoma case, where the patient had undergone radiotherapy for the bilateral neck and bilateral supraclavicular/infraclavicular area. Following completion of radiotherapy, the patient developed severe radiation pneumonitis.

  13. Synthesis of issues presented during the national committee for the follow-up of measures for radiotherapy of the 7 July 2011

    International Nuclear Information System (INIS)

    2011-08-01

    This report analyses the status of actions undertaken from July 2010 to July 2011 and regarding the support to the evolution of radiotherapy professions and care organization (increasing the number of radiotherapists, the possibility of welcoming radio-physics trainees, supporting the profession of technician in dosimetry), the vigilance system in radiotherapy, the implementation of authorizations and agreement criteria, and the 2009-2013 'cancer' plan for a better safety and quality of radiotherapy conditions

  14. Radiotherapy in bladder cancer

    International Nuclear Information System (INIS)

    Rozan, R.

    1992-01-01

    In 1992, the problem of the vesical radiotherapy is not resolved. The author presents the situation and the different techniques of radiotherapy in bladder cancers: external radiotherapy, only and associated with surgery, interstitial curietherapy and non-classical techniques as per operative radiotherapy, neutron therapy and concurrent radiotherapy with chemotherapy. In order to compare their efficiency, the five-year survival are given in all cases.(10 tabs)

  15. Study of antiproton flux of atmospheric origin in neighbourhood of the earth

    International Nuclear Information System (INIS)

    Huang, Ching-Yuan

    2002-01-01

    Secondary atmospheric antiprotons are studied. A parametrisation of the inclusive cross section for the p-bar production in p + p and p + A collisions is developed, based on the Quark Counting Rule, the Regge Phenomenology and data fitting. This parametrisation is shown to have a good agreement with experimental data for incident nucleon energy at least up to 24 GeV/n in the laboratory frame. By the analysis of the p-bar mean multiplicity distribution, this parametrisation can extend at least up to the centre of mass energy √s ∼ 25 GeV. Based on this well developed parametrisation, the Wounded Nucleon Model is applied to obtain the p-bar production cross section in A + A collisions. By including cosmic protons and α particles, the atmospheric p-bar flux at high balloon and satellite altitudes are calculated. The He-induced collisions are shown to contribute about 30 % in the total secondary atmospheric p-bar flux. It is observed that, for the search of the p-bar exotic origins such as the annihilation of supersymmetric dark matter (neutralino) and the evaporation of primordial black holes, the energy range up to E = 200 GeV/n for cosmic particles generating the secondary atmospheric p-bar production is the most important. It is shown that the secondary atmospheric p-bar flux used to correct the p-bar flux at TOA was underestimated in the previous works. In this work, the p-bar flux at TOA is then modified 10-15 % lower than the originally deduced, for the energy range E k > 1 GeV. A p-bar measurement experiment at the ground level is used to test the accuracy of secondary atmospheric p-bar production calculated by different works. The results of the BESS 1999 experiment at 2.77 km have confirmed the correctness of the present approach. At the AMS altitude, it is shown that the p-bar flux measured by AMS is almost the exact p-bar flux at TOA, with only 2-3 % of the atmospheric p-bar component. It is found that, even at very high altitudes, thousands of

  16. Review of backscatter measurement in kilovoltage radiotherapy using novel detectors and reduction from lack of underlying scattering material.

    Science.gov (United States)

    Eaton, David J; Doolan, Paul J

    2013-11-08

    Lack of underlying material can lead to dose reduction in kilovoltage radiotherapy treatments because of backscatter reduction. Conversely, the use of lead shielding can lead to large dose enhancement close to the lead interface. GAFCHROMIC film has been shown to be of use in verification of local backscatter factors compared to reference data in codes of practice, but careful handling and multiple readings are required to reduce systematic uncertainties to between 3% and 4%. Monte Carlo modeling of the specific treatment unit should be performed in cases which are found to differ from reference values before alternative values are adopted clinically, but these cases are expected to be few. GAFCHROMIC film may also be used to estimate backscatter reduction more readily than customized ionization chambers, for a range of beam qualities, applicator sizes and depth, with and without lead shielding. Differences were found between different studies, and it is not clear to what extent these are due to variation in equipment and/or technique. However, a layer of wax around lead shielding of 1 mm thickness should be sufficient to eliminate lead enhancement effects for all kilovoltage energies from 40 kV to 300 kV.

  17. Review of backscatter measurement in kilovoltage radiotherapy using novel detectors and reduction from lack of underlying scattering material

    Science.gov (United States)

    Doolan, Paul J.

    2013-01-01

    Lack of underlying material can lead to dose reduction in kilovoltage radiotherapy treatments because of backscatter reduction. Conversely, the use of lead shielding can lead to large dose enhancement close to the lead interface. GAFCHROMIC film has been shown to be of use in verification of local backscatter factors compared to reference data in codes of practice, but careful handling and multiple readings are required to reduce systematic uncertainties to between 3% and 4%. Monte Carlo modeling of the specific treatment unit should be performed in cases which are found to differ from reference values before alternative values are adopted clinically, but these cases are expected to be few. GAFCHROMIC film may also be used to estimate backscatter reduction more readily than customized ionization chambers, for a range of beam qualities, applicator sizes and depth, with and without lead shielding. Differences were found between different studies, and it is not clear to what extent these are due to variation in equipment and/or technique. However, a layer of wax around lead shielding of 1 mm thickness should be sufficient to eliminate lead enhancement effects for all kilovoltage energies from 40 kV to 300 kV PACS numbers: 87.55.Qr, 87.56.jk PMID:24257277

  18. Radiotherapy of bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Heilmann, H.P.

    1982-01-01

    Radiotherapy of branchogenic carcinoma comprises; palliative treatment, postoperative or pre-operative radiotherapy, radiotherapy as part of a combination of chemotherapy and radiotherapy of small cell carcinoma and curative radiotherapy of non-operable non-small cell carcinoma. Atelectasis and obstruction are indications for palliative radiotherapy. Postoperative radiotherapy is given only in cases of incomplete resection or mediastinal metastases. In the treatment of small cell carcinoma by combined irradiation and chemotherapy the mediastinum and primary tumour are irradiated, generally after chemotherapy, and the C.N.S. receives prophylactic radiotherapy. Curative radiotherapy is indicated in cases of non-operable small cell carcinoma. Irradiation with doses of 60-70 Gy produced 5-years-survival rates of 10-14% in cases classified as T 1 -T 2 N 0 M 0 . (orig.) [de

  19. Indirect Search for Dark Matter with AMS in Positrons, Gamma and Antiprotons Channels

    Science.gov (United States)

    Casadei, D.

    2007-11-01

    The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station, will provide data on cosmic radiations in a large energy range. The main physics goals in the astroparticle domain are the antimatter and the dark matter searches. Dark matter should be composed of non baryonic weakly interacting massive particles, a good candidate being the lightest SUSY particle in R-parity conserving models. As a prototype for the AMS-02 experiment, the AMS-01 particle spectrometer was flown on the Space Shuttle Discovery in near earth orbit for a ten day mission in June 1998. The direct identification of positrons in AMS-01 was limited to energies below 3 GeV due to the vast proton background and the characteristics of the subdetectors, but the sensitivity towards higher energies (up to 40 GeV) was extended by identifying positrons through the conversion of bremsstrahlung photons. AMS-02 will greatly improve the accuracy on the positron spectrum, which will be measured up to 300 GeV, together with the antiproton and γ-ray flux, thus providing a unique chance to measure all relevant neutralino decay channels with the same experiment.

  20. Evaluation on Geant4 Hadronic Models for Pion Minus, Pion Plus and Neutron Particles as Major Antiproton Annihilation Products.

    Science.gov (United States)

    Tavakoli, Mohammad Bagher; Mohammadi, Mohammad Mehdi; Reiazi, Reza; Jabbari, Keyvan

    2015-01-01

    Geant4 is an open source simulation toolkit based on C++, which its advantages progressively lead to applications in research domains especially modeling the biological effects of ionizing radiation at the sub-cellular scale. However, it was shown that Geant4 does not give a reasonable result in the prediction of antiproton dose especially in Bragg peak. One of the reasons could be lack of reliable physic model to predict the final states of annihilation products like pions. Considering the fact that most of the antiproton deposited dose is resulted from high-LET nuclear fragments following pion interaction in surrounding nucleons, we reproduced depth dose curves of most probable energy range of pions and neutron particle using Geant4. We consider this work one of the steps to understand the origin of the error and finally verification of Geant4 for antiproton tracking. Geant4 toolkit version 9.4.6.p01 and Fluka version 2006.3 were used to reproduce the depth dose curves of 220 MeV pions (both negative and positive) and 70 MeV neutrons. The geometry applied in the simulations consist a 20 × 20 × 20 cm(3) water tank, similar to that used in CERN for antiproton relative dose measurements. Different physic lists including Quark-Gluon String Precompound (QGSP)_Binary Cascade (BIC)_HP, the recommended setting for hadron therapy, were used. In the case of pions, Geant4 resulted in at least 5% dose discrepancy between different physic lists at depth close to the entrance point. Even up to 15% discrepancy was found in some cases like QBBC compared to QGSP_BIC_HP. A significant difference was observed in dose profiles of different Geant4 physic list at small depths for a beam of pions. In the case of neutrons, large dose discrepancy was observed when LHEP or LHEP_EMV lists were applied. The magnitude of this dose discrepancy could be even 50% greater than the dose calculated by LHEP (or LHEP_EMV) at larger depths. We found that effect different Geant4 physic list in

  1. Constraining pre big-bang-nucleosynthesis expansion using cosmic antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Schelke, M. [Istituto Nazionale di Fisica Nucleare, Torino (Italy); Catena, R. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Fornengo, N. [Torino Univ. (Italy). Dipt. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Torino (Italy); Masiero, A. [Pavoa Univ. (Italy). Dipt. di Fisica]|[Istituto Nazionale di Fisica Nucleare, Padova (Italy); Pietroni, M. [Istituto Nazionale di Fisica Nucleare, Padova (Italy)

    2006-06-15

    A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity tests, may nevertheless lead to enhancements of the Hubble rate up to many orders of magnitude. In this paper we show that strong bounds on the pre-BBN evolution of the Universe may be derived, under the assumption that dark matter is a thermal relic, by combining the dark matter relic density bound with constraints coming from the production of cosmic-ray antiprotons by dark matter annihilation in the Galaxy. The limits we derive can be sizable and apply to the Hubble rate around the temperature of dark matter decoupling. For dark matter masses lighter than 100 GeV, the bound on the Hubble-rate enhancement ranges from a factor of a few to a factor of 30, depending on the actual cosmological model, while for a mass of 500 GeV the bound falls in the range 50-500. Uncertainties in the derivation of the bounds and situations where the bounds become looser are discussed. We finally discuss how these limits apply to some specific realizations of non-standard cosmologies: a scalar-tensor gravity model, kination models and a Randall-Sundrum D-brane model. (Orig.)

  2. Cooling of ions and antiprotons with magnetized electrons

    CERN Document Server

    Mollers, B; Walter, M; Zwicknagel, G; Carli, Christian; Nersisyan, H

    2004-01-01

    Electron cooling is a well-established method to improve the phase space quality of ion beams in storage rings. More recently antiprotons have been cooled in traps, first by electrons and then by positrons in order to produce antihydrogen atoms as simplest form of antimatter for CPT-tests. During these cooling processes the light particles are guided by strong external magnetic fields which imposes a challenge to the theoretical description. Within the binary collision model we treat the Coulomb interaction as second-order perturbation to the helix motion of the light particles and also by numerical simulations. In the complementary dielectric theory we calculate the polarization of the light particles by solving the nonlinear Vlasov-Poisson equation as well as linear response. It turns out that the linearization becomes dubious at low ion velocities. In the presence of a strong magnetic field the numerically expensive solution of the Vlasov-Poisson equation is the method of choice, alternatively one may empl...

  3. Procedure to measure the neutrons spectrum around a lineal accelerator for radiotherapy; Procedimiento para medir el espectro de los neutrones en torno a un acelerador lineal para radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Hernandez D, V. M.; Letechipia de L, C. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico); Benites R, J. L. [Servicios de Salud de Nayarit, Centro Estatal de Cancerologia, Calzada de la Cruz 116 Sur, 63000 Tepic, Nayarit (Mexico); Salas L, M. A., E-mail: fermineutron@yahoo.com [Universidad Autonoma de Zacatecas, Unidad Academica de Agronomia, Apdo. Postal 336, 98000 Zacatecas (Mexico)

    2013-10-15

    An experimental procedure was developed, by means of Bonner spheres, to measure the neutrons spectrum around Linacs of medical use that only requires of a single shot of the accelerator; to this procedure we denominate Planetary or Isocentric method. One of the problems associated to the neutrons spectrum measurement in a radiotherapy room with lineal accelerator is because inside the room a mixed, intense and pulsed radiation field takes place affecting the detection systems based on active detector; this situation is solved using a passive detector. In the case of the Bonner spheres spectrometer the active detector has been substituted by activation detectors, trace detectors or thermoluminescent dosimeters. This spectrometer uses several spheres that are situated one at a time in the measurement point, this way to have the complete measurements group the accelerator should be operated, under the same conditions, so many times like spheres have the spectrometer, this activity can consume a long time and in occasions due to the work load of Linac to complicate the measurement process too. The procedure developed in this work consisted on to situate all the spectrometer spheres at the same time and to make the reading by means of a single shot, to be able to apply this procedure, is necessary that before the measurements two characteristics are evaluated: the cross-talking of the spheres and the symmetry conditions of the neutron field. This method has been applied to determine the photo-neutrons spectrum produced by a lineal accelerator of medical use Varian ix of 15 MV to 100 cm of the isocenter located to 5 cm of depth of a solid water mannequin of 30 x 30 x 15 cm. The spectrum was used to determine the total flow and the environmental dose equivalent. (Author)

  4. Modeling of the Near-Earth Low-Energy Antiproton Fluxes

    Directory of Open Access Journals (Sweden)

    U. B. Jayanthi

    2011-01-01

    Full Text Available The local interstellar antiproton spectrum is simulated taking into account antineutron decay, (He,p interaction, secondary and tertiary antiproton production, and the solar modulation in the “force field” approximation. Inclusive invariant cross-sections were obtained through a Monte Carlo procedure using the Multistage Dynamical Model code simulating various processes of the particle production. The results of the simulations provided flux values of 4⋅10−3 to 10−2 and 10−2 to 1.7⋅10−2 antiprotons/(2 s sr GeV at energies of 0.2 and 1 GeV, respectively, for the solar maximum and minimum epochs. Simulated flux of the trapped antiprotons in the inner magnetosphere due to galactic cosmic ray (GCR interactions with the atmospheric constituents exceeds the galactic antiproton flux up to several orders. These simulation results considering the assumptions with the attendant limitations are in comprehensive agreement with the experimental data including the PAMELA ones.

  5. Properties of W + jet events in proton-antiproton collisions at 1.8 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Drucker, Robert Brian [Univ. of California, Berkeley, CA (United States). Dept. of Physics

    1993-11-22

    W boson + QCD Jet events, produced in 1.8 TeV proton-antiproton collisions and measured by the Collider Detector at Fermilab (CDF), were used to measure the center-of-mass production angle of the W + jet system, and were also used to place limits on the production of excited quark states. The center-of-mass production angular distribution agrees well with leading order and next-to-leading order QCD predictions. Excited quark states were searched for in the reaction q + g → q* → q + W. Upper limits on the q* cross section, as a function of the q* mass, are shown. Comparison with a theoretical prediction for q* production excludes excited quark states with a mass in the range 150--530 GeV/c2, at 95% confidence.

  6. Dosimetry in radiotherapy. V.1

    International Nuclear Information System (INIS)

    1988-01-01

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  7. Dosimetry in radiotherapy. V.2

    International Nuclear Information System (INIS)

    1988-01-01

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  8. National arrangements for radiotherapy

    International Nuclear Information System (INIS)

    2007-01-01

    After a presentation of several letters exchanged between the French health ministry and public agencies in charge of public health or nuclear safety after a radiotherapy accident in Epinal, this report comments the evolution of needs in cancerology care and the place given to radiotherapy. It outlines the technological and organisational evolution of radiotherapy and presents the distribution of radiotherapy equipment, of radio-therapists and other radiotherapy professionals in France. Within the context of radiotherapy accidents which occurred in 2007, it presents the regulatory arrangements which aimed at improving the safety, short term and middle term arrangements which are needed to support and structure radiotherapy practice quality. It stresses the fact that the system will deeply evolve by implementing a radiotherapy vigilance arrangement and a permanent follow-on and adaptation plan based on surveys and the creation of a national committee

  9. Interlaboratory comparisons in kerma in the air measures and absorbed dose in water using 60Co beams in radiotherapy

    International Nuclear Information System (INIS)

    Rosado, Paulo Henrique Goncalves; Silva, Cosme Norival Mello da

    2013-01-01

    In order to ensure that the measures of a quantity have high reliability and traceability interlaboratory comparisons are performed. The LNMRI has participated in several these interlaboratory comparisons. In the period 2000-2013 the LNMRI participated in 5 interlaboratory comparisons for measurement of kerma coefficients in the air and absorbed dose coefficients in the water. The results of interlaboratory comparisons indicate that the measures taken are appropriate to the LNMRI regarding the accuracy and precision measuring of these quantities

  10. Assessment of patient-reported measures of bowel function before and after pelvic radiotherapy: an ancillary study of the North Central Cancer Treatment Group study N00CA.

    Science.gov (United States)

    Atherton, Pamela J; Halyard, Michele Y; Sloan, Jeff A; Miller, Robert C; Deming, Richard L; Tai, T H Patricia; Stien, Kathy J; Martenson, James A

    2013-04-01

    The Bowel Function Questionnaire (BFQ) has been used in clinical trials to assess symptoms during and after pelvic radiotherapy (RT). This study evaluated the importance of symptoms in the BFQ from a patient perspective. Patients reported presence or absence of symptoms and rated importance of symptoms at baseline, 4 weeks after completion of pelvic RT, and 12 and 24 months after RT. The BFQ measured overall quality of life (QOL) and symptoms of nocturnal bowel movements, incontinence, clustering, need for protective clothing, inability to differentiate stool from gas, liquid bowel movements, urgency, cramping, and bleeding. Bowel movement frequency also was recorded. A content validity questionnaire (CVQ) was used to rate symptoms as "not very important," "moderately unimportant," "neutral," "moderately important," or "very important." Most of the 125 participating patients rated all symptoms as moderately or very important. Generally, patients gave similar ratings for symptom importance at all study points, and ratings were independent of whether the patient experienced the symptom. Measures of greatest importance (moderately or very important) at baseline were ability to control bowel movements (94 %), not having to wear protective clothing (90 %), and not having rectal bleeding (94 %). With the exception of need for protective clothing, the presence of a symptom at 4 weeks was associated with significantly worse QOL (P < .01 for all). The BFQ has excellent content validity. Patients rated most symptoms as moderately or very important, indicating the BFQ is an appropriate tool for symptom assessment during and after pelvic RT.

  11. A self-consistent model for the Galactic cosmic ray, antiproton and positron spectra

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    In this talk I will present the escape model of Galactic cosmic rays. This model explains the measured cosmic ray spectra of individual groups of nuclei from TeV to EeV energies. It predicts an early transition to extragalactic cosmic rays, in agreement with recent Auger data. The escape model also explains the soft neutrino spectrum 1/E^2.5 found by IceCube in concordance with Fermi gamma-ray data. I will show that within the same model one can explain the excess of positrons and antiprotons above 20 GeV found by PAMELA and AMS-02, the discrepancy in the slopes of the spectra of cosmic ray protons and heavier nuclei in the TeV-PeV energy range and the plateau in cosmic ray dipole anisotropy in the 2-50 TeV energy range by adding the effects of a 2 million year old nearby supernova.

  12. Two Photon Decay Widths of Charmonium Resonances Formed in Proton Antiproton Annihilations

    Energy Technology Data Exchange (ETDEWEB)

    Stancari, Michelle Dawn [UC, Irvine

    1999-01-01

    E835 is an experiment dedicated to the precision study of charmonium formed in $\\bar{p}p$ annihilations at the Fermilab Antiproton Accumulator. E835 has measured the resonance parameters of the $\\eta_c$ resonance: $M(\\eta_c$) = 2985.4 $\\pm$ 2.1 MeV, ,($\\eta_c$) = 21.1 $\\pm$ $^{7.5}_{6.2}$ MeV, and, ($\\eta_c \\to \\gamma\\gamma$ ) = 3.9 $^{1.5}_{ 1.3}$ $\\pm$ $^{1.8}_ {1.1}$. Also reported is the two photon width of the $X_2$,,($X_2 \\to \\gamma\\gamma$) = 0.29 $\\pm$ 0.06 $\\pm$ 0:04. A search for the $\\eta^{\\prime}_c$ resonance has resulted in an upper limit for the product of the branching ratios $B(\\eta^{\\prime}_c \\to \\bar{p}p$) x $B(\\eta^{\\prime}_c \\to \\gamma\\gamma$ ) < 12 x $10^{-8}$. An upper limit, ($\\chi_0 \\to \\gamma\\gamma$) < 2.7 keV is set.

  13. Dark matter annihilations into two light fermions and one gauge boson. General analysis and antiproton constraints

    International Nuclear Information System (INIS)

    Garny, Mathias; Ibarra, Alejandro; Vogl, Stefan

    2011-12-01

    We study in this paper the scenario where the dark matter is constituted by Majo- rana particles which couple to a light Standard Model fermion and an extra scalar via a Yukawa coupling. In this scenario, the annihilation rate into the light fermions with the mediation of the scalar particle is strongly suppressed by the mass of the fermion. Nevertheless, the helicity suppression is lifted by the associated emission of a gauge boson, yielding annihilation rates which could be large enough to allow the indirect detection of the dark matter particles. We perform a general analysis of this scenario, calculating the annihilation cross section of the processes χχ → f anti fV when the dark matter particle is a SU(2) L singlet or doublet, f is a lepton or a quark, and V is a photon, a weak gauge boson or a gluon. We point out that the annihilation rate is particularly enhanced when the dark matter particle is degenerate in mass to the intermediate scalar particle, which is a scenario barely constrained by collider searches of exotic charged or colored particles. Lastly, we derive upper limits on the relevant cross sections from the non-observation of an excess in the cosmic antiproton-to-proton ratio measured by PAMELA. (orig.)

  14. Possible Dark Matter Annihilation Signal in the AMS-02 Antiproton Data.

    Science.gov (United States)

    Cui, Ming-Yang; Yuan, Qiang; Tsai, Yue-Lin Sming; Fan, Yi-Zhong

    2017-05-12

    Using the latest AMS-02 cosmic-ray antiproton flux data, we search for a potential dark matter annihilation signal. The background parameters about the propagation, source injection, and solar modulation are not assumed a priori but based on the results inferred from the recent B/C ratio and proton data measurements instead. The possible dark matter signal is incorporated into the model self-consistently under a Bayesian framework. Compared with the astrophysical background-only hypothesis, we find that a dark matter signal is favored. The rest mass of the dark matter particles is ∼20-80  GeV, and the velocity-averaged hadronic annihilation cross section is about (0.2-5)×10^{-26}  cm^{3} s^{-1}, in agreement with that needed to account for the Galactic center GeV excess and/or the weak GeV emission from dwarf spheroidal galaxies Reticulum 2 and Tucana III. Tight constraints on the dark matter annihilation models are also set in a wide mass region.

  15. Search for Λ–Λ hyperuclei using antiprotons in PANDA

    Directory of Open Access Journals (Sweden)

    Introzzi R.

    2014-06-01

    Full Text Available The Double Hypernuclei are the only systems that allow to study the hyperon-hyperon interaction because the hyperon-hyperon scattering experiments are at present impossible. Experimental data are still very scarce, due to the difficulty of producing the doubly strange hyperon Ξ−, from which a double hypernucleus is formed. The formation of such a hypernucleus proceeds through a multiple-step process and the measurement of the relevant parameters (e.g. energy separation and decay branching ratios requires high statistics. The PANDA Collaboration planned to exploit the intense beam of the HESR machine at the future facility FAIR to produce Ξ− hyperons from antiproton annihilation in nuclei. A 12C target will be inserted inside the ring: the sizes of the target and the beam spot overlap play a crucial role to avoid serious damage of beam and detectors. The status of the art of the present data, the design of the optimized target and the tests on the prototype will be presented.

  16. Cosmic ray propagation in a diffusion model: a new estimation of the diffusion parameters and of the secondary antiprotons flux; Propagation des rayons cosmiques dans un modele de diffusion: une nouvelle estimation des parametres de diffusion et du flux d'antiprotons secondaires

    Energy Technology Data Exchange (ETDEWEB)

    Maurin, D

    2001-02-01

    Dark matter is present at numerous scale of the universe (galaxy, cluster of galaxies, universe in the whole). This matter plays an important role in cosmology and can not be totally explained by conventional physic. From a particle physic point of view, there exists an extension of the standard model - supersymmetry - which predicts under certain conditions the existence of new stable and massive particles, the latter interacting weakly with ordinary matter. Apart from direct detection in accelerators, various indirect astrophysical detection are possible. This thesis focuses on one particular signature: disintegration of these particles could give antiprotons which should be measurable in cosmic rays. The present study evaluates the background corresponding to this signal i. e. antiprotons produced in the interactions between these cosmic rays and interstellar matter. In particular, uncertainties of this background being correlated to the uncertainties of the diffusion parameter, major part of this thesis is devoted to nuclei propagation. The first third of the thesis introduces propagation of cosmic rays in our galaxy, emphasizing the nuclear reaction responsibles of the nuclei fragmentation. In the second third, different models are reviewed, and in particular links between the leaky box model and the diffusion model are recalled (re-acceleration and convection are also discussed). This leads to a qualitative discussion about information that one can infer from propagation of these nuclei. In the last third, we finally present detailed solutions of the bidimensional diffusion model, along with constrains obtained on the propagation parameters. The latter is applied on the antiprotons background signal and it concludes the work done in this thesis. The propagation code for nuclei and antiprotons used here has proven its ability in data analysis. It would probably be of interest for the analysis of the cosmic ray data which will be taken by the AMS experiment on

  17. Upper limit to antiproton flux in cosmic radiation above 100 GeV using muon charge ratio

    Science.gov (United States)

    Stephens, S. A.

    1983-01-01

    Upper limits to the fraction of antiprotons in cosmic radiation have been estimated from the observed charge ratio of muons at sea-level. Using these values, it is shown that constraints can be set on the extragalactic hypothesis of the observed antiprotons in the framework of energy-dependent confinement of cosmic rays in the galaxy.

  18. Review of the High Performance Antiproton Trap (HiPAT) experiment

    Science.gov (United States)

    Martin, James J.; Lewis, Raymond A.; Boise Pearson, J.; Sims, W. Herb; Chakrabarti, Suman; Fant, Gene; McDonald, Stan

    2003-10-01

    Many space propulsion concepts exist that use matter-antimatter reactions. Current antiproton production rates are enough to conduct proof-of-principle evaluation of these concepts. One enabling technology for such experiments is portable storage of low energy antiprotons, to transport antiprotons to experimental facilities. To address this need, HiPAT is being developed, with a design goal of containing 10^12 particles for up to 18 days. HiPAT is a Penning-Malmberg trap with a 4 Telsa superconductor, 20 kV electrodes, radio frequency (RF) network, and 10-13 Torr vacuum. "Normal" matter is being used to evaluate the system. An electron beam ionizes background gas in situ, and particle beams are captured dynamically. The experiment examines ion storage lifetimes, RF plasma diagnostics, charge exchange with background gases, and dynamic ion beam capture.

  19. Design for antiproton collection and beam transport in the Fermilab Tevatron I project

    Energy Technology Data Exchange (ETDEWEB)

    Colton, E.; Hojvat, C.

    1983-03-01

    120-GeV protons from the Main Ring will be used to produce 8-GeV antiprotons. A pulsed lithium lens collects and matches the antiprotons to a beam line for injection into the Debuncher Ring. The anti p beam has a transverse emittance of 20..pi.. mm-mr and a deltap/p = +-2.0%. The beam line consists of a clean-up section with vertical emittance selection, two long dispersion free sections, a bend and a vertical injector. Antiprotons with a transverse emittance of 2..pi.. mm-mr and deltap/p = +-7.0 x 10/sup -4/ are transported in the reverse direction, bypassing the target area, and along the 120-GeV proton transport line for reverse injection in the Main Ring.

  20. QCD studies with anti-protons at FAIR: Indian participation in PANDA

    International Nuclear Information System (INIS)

    Kailas, S.; Roy, B.J.; Dutta, D.; Jha, V.; Varma, R.

    2011-01-01

    The Facility for Antiproton and Ion Research (FAIR) is a future project at GSI which will extend hadron physics studies up to the charm meson region using antiproton beams together with a state-of-the-art detector antiproton annihilation at Darmstadt (PANDA). The physics aim, in a broader sense, is to address the fundamental problems of hadron physics and aspects of quantum chromo-dynamics (QCD) at low energies. The proposed work in India will consist of several parts: R and D studies of silicon micro-strip detector, development of a scintillator hodoscope with silicon photomultiplier (SiPM) readout, studies of SiPM as photon counter and simulation studies of the detector design as well as physics case studies. The present article describes the physics motivation and initial progress made towards achieving these goals. (author)

  1. Status of antiproton accumulation and cooling at Fermilab's Recycler

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Bhat, C.M.; Broemmelsiek, D.; Burov, A.; Carlson, K.; Crisp, J.; Derwent, P.; Eddy, N.; Gattuso, C.; Hu, M.; Pruss, S.; /Fermilab

    2009-08-01

    The Recycler ring is an 8 GeV permanent magnet storage ring where antiprotons are accumulated and prepared for Fermilab's Tevatron Collider program. With the goal of maximizing the integrated luminosity delivered to the experiments, storing, cooling and extracting antiprotons with high efficiency has been pursued. Over the past two years, while the average accumulation rate doubled, the Recycler continued to operate at a constant level of performance thanks to changes made to the Recycler Electron Cooler (energy stability and regulation, electron beam optics), RF manipulations and operating procedures. In particular, we discuss the current accumulation cycle in which {approx} 400 x 10{sup 10} antiprotons are accumulated and extracted to the Tevatron every {approx}15 hours.

  2. Charge asymmetry in alignment of atoms excited by protons and antiprotons

    International Nuclear Information System (INIS)

    Balashov, V.V.; Sokolik, A.A.; Stysin, A.V.

    2007-01-01

    The multichannel diffraction approximation is used to consider excitation of lithium atom by proton and antiproton impact. Calculations are performed for the energy range 100 keV - 1 MeV of incoming proton and anti-proton which should be reliable enough due to the general requirements of the multichannel diffraction approximation. The sign-of-charge effect in the alignment of produced 1s 2 3d excited state and in the linear polarization of the subsequent spontaneous 1s 2 3d → 1s 2 2p radiation is expected to be considerable. The clear sign-of-charge effect in the polarization occurs for projectile energies below 1 MeV and become stronger when going to lower energies and the difference between the proton case and the anti-proton one looks considerable enough for experimental observation

  3. Antiproton-proton annihilation into light neutral meson pairs within an effective meson theory

    Science.gov (United States)

    Wang, Ying; Bystritskiy, Yury M.; Ahmadov, Azad I.; Tomasi-Gustafsson, Egle

    2017-08-01

    Antiproton-proton annihilation into light neutral mesons in the few GeV energy domain is investigated in view of a global description of the existing data and predictions for future work at the Antiproton Annihilation at Darmstadt (PANDA) experiment at the Facility for Antiproton and Ion Research (FAIR). An effective meson model earlier developed, with mesonic and baryonic degrees of freedom in s , t , and u channels, is applied here to π0π0 production. Form factors with logarithmic s and t (u ) dependencies are applied. A fair agreement with the existing angular distributions is obtained. Applying SU(3) symmetry, it is straightforward to recover the angular distributions for π0η and η η production in the same energy range. A good agreement is generally obtained with all existing data.

  4. The experiment PANDA: physics with antiprotons at FAIR

    Science.gov (United States)

    Boca, Gianluigi

    2015-05-01

    PANDA is an experiment that will run at the future facility FAIR, Darmstadt, Germany. A high intensity and cooled antiproton beam will collide on a fixed hydrogen or nuclear target covering center-of-mass energies between 2.2 and 5.5 GeV. PANDA addresses various physics aspects from the low energy non-perturbative region towards the perturbative regime of QCD. With the impressive theoretical developments in this field, e.g. lattice QCD, the predictions are becoming more accurate in the course of time. The data harvest with PANDA will, therefore, be an ideal test bench with the aim to provide a deeper understanding of hadronic phenomena such as confinement and the generation of hadron masses. A variety of physics topics will be covered with PANDA, for example: the formation or production of exotic non-qqbar charm meson states connected to the recently observed XYZ spectrum; the study of gluon-rich matter, such as glueballs and hybrids; the spectroscopy of the excited states of strange and charm baryons, their production cross section and their spin correlations; the behaviour of hadrons in nuclear matter; the hypernuclear physics; the electromagnetic proton form factors in the timelike region. The PANDA experiment is designed to achieve the above mentioned physics goals with a setup with the following characteristics: an almost full solid angle acceptance; excellent tracking capabilities with high resolution (1-2 % at 1 GeV/c in the central region); secondary vertex detection with resolution ≈ 100 microns or better; electromagnetic calorimetry for detections of gammas and electrons up to 10 GeV; good particle identification of charge tracks (electrons, muons, pions, kaons, protons); a dedicated interchangeable central apparatus for the hypernuclear physics; detector and data acquisition system capable of working at 20 MHz interaction rate with an intelligent software trigger that can provide maximum flexibility.

  5. Comparison of intensity-modulated radiotherapy and volumetric-modulated arc therapy dose measurement for head and neck cancer using optical stimulated luminescence dosimeter

    Science.gov (United States)

    Lai, Lu-Han; Chuang, Keh-Shih; Lin, Hsin-Hon; Liu, Yi-Chi; Kuo, Chiung-Wen; Lin, Jao-Perng

    2017-11-01

    The in-vivo dose distributions of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT), a newly developed technique, for head and neck cancer have been investigated for several years. The present study used a head-and-neck RANDO phantom to simulate the clinical conditions of nasopharyngeal carcinoma and compare the radiation doses between VMAT and IMRT. Three types of planning target volume (PTV) profiles were targeted by reducing the PTV surface margin by 0, 3, and 5 mm. An optically stimulated luminescence dosimeter was used to measure the surface doses. The results revealed that VMAT provided on average 16.8-13.8% lower surface doses within the PTV target areas than IMRT. When the PTV margin was reduced by 0 mm, the surface doses for IMRT reached their maximum value, accounting for 75.1% of its prescribed dose (Dp); however, the Dp value of VMAT was only 61.1%. When the PTV margin was reduced by 3 or 5 mm, the surface doses decreased considerably. The observed surface doses were insufficient when the tumours invaded the body surface; however, VMAT exerted larger skin-sparing effects than IMRT when the tumours away from the skin. These results suggest that the skin doses for these two techniques are insufficient for surface tumours. Notably, VMAT can provide lower skin doses for deep tumours.

  6. Case report of a near medical event in stereotactic radiotherapy due to improper units of measure from a treatment planning system.

    Science.gov (United States)

    Gladstone, D J; Li, S; Jarvis, L A; Hartford, A C

    2011-07-01

    The authors hereby notify the Radiation Oncology community of a potentially lethal error due to improper implementation of linear units of measure in a treatment planning system. The authors report an incident in which a patient was nearly mistreated during a stereotactic radiotherapy procedure due to inappropriate reporting of stereotactic coordinates by the radiation therapy treatment planning system in units of centimeter rather than in millimeter. The authors suggest a method to detect such errors during treatment planning so they are caught and corrected prior to the patient positioning for treatment on the treatment machine. Using pretreatment imaging, the authors found that stereotactic coordinates are reported with improper linear units by a treatment planning system. The authors have implemented a redundant, independent method of stereotactic coordinate calculation. Implementation of a double check of stereotactic coordinates via redundant, independent calculation is simple and accurate. Use of this technique will avoid any future error in stereotactic treatment coordinates due to improper linear units, transcription, or other similar errors. The authors recommend an independent double check of stereotactic treatment coordinates during the treatment planning process in order to avoid potential mistreatment of patients.

  7. Case report of a near medical event in stereotactic radiotherapy due to improper units of measure from a treatment planning system

    International Nuclear Information System (INIS)

    Gladstone, D. J.; Li, S.; Jarvis, L. A.; Hartford, A. C.

    2011-01-01

    Purpose: The authors hereby notify the Radiation Oncology community of a potentially lethal error due to improper implementation of linear units of measure in a treatment planning system. The authors report an incident in which a patient was nearly mistreated during a stereotactic radiotherapy procedure due to inappropriate reporting of stereotactic coordinates by the radiation therapy treatment planning system in units of centimeter rather than in millimeter. The authors suggest a method to detect such errors during treatment planning so they are caught and corrected prior to the patient positioning for treatment on the treatment machine. Methods: Using pretreatment imaging, the authors found that stereotactic coordinates are reported with improper linear units by a treatment planning system. The authors have implemented a redundant, independent method of stereotactic coordinate calculation. Results: Implementation of a double check of stereotactic coordinates via redundant, independent calculation is simple and accurate. Use of this technique will avoid any future error in stereotactic treatment coordinates due to improper linear units, transcription, or other similar errors. Conclusions: The authors recommend an independent double check of stereotactic treatment coordinates during the treatment planning process in order to avoid potential mistreatment of patients.

  8. Beam-energy dependence of the directed flow of protons, antiprotons, and pions in Au+Au collisions.

    Science.gov (United States)

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Levine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-04-25

    Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

  9. Beam-Energy Dependence of the Directed Flow of Protons, Antiprotons, and Pions in Au+Au Collisions

    Science.gov (United States)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

    2014-04-01

    Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y =0) are reported in √sNN =7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

  10. Observation and study of bottom-meson decays to a charm meson, a proton-antiproton pair, and pions

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tae Min [Univ. of California, Santa Barbara, CA (United States)

    2010-04-27

    Bottom-meson decays with baryons show two unusual features—the branching fractions are enhanced for multibody decays and the baryon-antibaryon subsystem recoils against the other decay products—and their reasons are not yet well understood. Moreover, measurements using explicit reconstruction techniques constitute only about 1% out of about 8% of such decays. This Dissertation reports the study of ten bottom-meson decays (labeled 0– 9) to a proton-antiproton pair, a charm meson, and a system of up to two pions, using the BABAR Experiment’s 455×106 BB pairs produced with the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center.

  11. Radiotherapy for Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena [Rigshospitalet Copenhagen Univ. (Denmark). Depts. of Oncology and Haematology; Yahalom, Joachim (eds.) [Memorial Sloan-Kettering Cancer, New York, NY (United States). Dept. of Radiation Oncology

    2011-07-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  12. Radiotherapy for Hodgkin lymphoma

    International Nuclear Information System (INIS)

    Specht, Lena; Yahalom, Joachim

    2011-01-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  13. Dispersion suppression with missing magnets in a FODO structure - application to the CERN Antiproton Accumulator

    CERN Document Server

    Autin, Bruno

    1979-01-01

    The lattice of an antiproton accumulator which uses the stochastic cooling method must meet a variety of requirements arising from its double function: storing particles in momentum space, and reducing their phase space volume in both transverse and longitudinal dimensions. A number of long straight sections, some of them with a zero momentum dispersion function alpha /sub p/, are required and have to be disposed on a relatively small circumference. Firstly, a systematic analysis of dipole distributions in a dispersion suppressor is presented. Then the requirements to be fulfilled by the lattice of an antiproton accumulator are listed and serve as criteria for the choice of a scheme of dispersion suppressor. (4 refs).

  14. Quenching of metastable antiprotonic helium atoms in collisions with deuterium molecules

    CERN Document Server

    Juhász, B; Hayano, R S; Hori, Masaki; Horváth, D; Ishikawa, T; Sakaguchi, J; Torii, H A; Widmann, E; Yamaguchi, H; Yamazaki, T

    2002-01-01

    Quenching of metastable antiprotonic helium atoms in collisions with deuterium molecules has been studied using laser spectroscopy at CERN's new Antiproton Decelerator facility. The quenching cross- sections of the states (n, l)=(39, 36), (39, 37), and (39, 38) were determined from the decay rates of the states which were observed using the "deuterium-assisted inverse resonance" (DAIR) method. The results. revealed a similar (n, l)-dependence of the quenching cross- sections as in the case of hydrogen but the values were smaller by a factor of ~1.5. (27 refs).

  15. Heating 197Au nuclei with 8 GeV antiproton and π- beams

    International Nuclear Information System (INIS)

    Back, B.; Beaulieu, L.; Breuer, H.; Gushue, S.; Hsi, W.-C.; Korteling, R. G.; Kwiatkowski, K.; Laforest, R.; Lefort, T.; Martin, E.; Pienkowski, L.; Ramakrishnan, E.; Remsberg, L. P.; Viola, V. E.

    1999-01-01

    This contribution stresses results recently obtained from experiment E900 performed at the Brookhaven AGS accelerator with 8 GeV/c antiproton and negative pion beams using the Indiana Silicon Sphere detector array. An investigation of the reaction mechanism is presented, along with source characteristics deduced from a two-component fit to the spectra. An enhancement of deposition energy with the antiproton beam with respect to the pion beam is observed. The results are qualitatively consistent with predictions of an intranuclear cascade code

  16. Heating {sup 197}Au nuclei with 8 GeV antiproton and {pi}- beams.

    Energy Technology Data Exchange (ETDEWEB)

    Back, B.; Beaulieu, L.; Breuer, H.; Gushue, S.; Hsi, W.-C.; Korteling, R. G.; Kwiatkowski, K.; Laforest, R.; Lefort, T.; Martin, E.; Pienkowski, L.; Ramakrishnan, E.; Remsberg, L. P.; Viola, V. E.

    1999-05-03

    This contribution stresses results recently obtained from experiment E900 performed at the Brookhaven AGS accelerator with 8 GeV/c antiproton and negative pion beams using the Indiana Silicon Sphere detector array. An investigation of the reaction mechanism is presented, along with source characteristics deduced from a two-component fit to the spectra. An enhancement of deposition energy with the antiproton beam with respect to the pion beam is observed. The results are qualitatively consistent with predictions of an intranuclear cascade code.

  17. Two Photon Decays of Charmonium States Produced in Proton - Anti-proton Annihilations

    Energy Technology Data Exchange (ETDEWEB)

    Fast, James Elliot [UC, Irvine

    1992-01-01

    The two photon decays of the $\\eta_c$ and $\\chi_2$ charmonium states have been measured in $p\\bar{p}$ annihilation using the E760 apparatus at Fermilab during the 1990-1991 fixed target run. A search for the $\\eta^\\prime_c$ resonance decaying into two photons has also been conducted. The processes $p\\bar{p} \\to R \\to \\gamma \\gamma$ have been measured using a cooled beam of antiprotons circulating in the Fermilab accumulator ring intersecting an internal hydrogen gas-jet target. The final state photons were measured with a high granularity, high resolution lead glass calorimeter. From a scan of the $\\eta_c$ resonance region, the mass, the total width, and the branching ratio to two photons have been measured. The results are $M_{\\eta_c}$ = 2989.9 ± 2.2 ±0.4 MeV/$c^2$, $\\Gamma_{\\eta_c}$ = 15.6±6.9±6.4 MeV, and $BR({\\eta_c} \\to \\gamma \\gamma)$ = (2.77 ± 1.19 ± 0.43) x $10^{-4}$. Data were taken at the peak of the $X_2$ resonance, and the two photon branching ratio was determined to be $BR(X_2 \\to \\gamma \\gamma)$ = (1.54 ± 0.40 ± 0.24) x $10^{-4}$. Data were collected at several energies around the expected mass of the $\\eta^\\prime_c$. Upper limits have been placed on the product of branching ratios, $BR(\\eta^\\prime_c \\to p\\bar{p})BR(\\eta^\\prime_c \\to \\gamma \\gamma)$, as function of the $\\eta^\\prime_c$ mass and total width.

  18. 11C-methionine PET, a novel method for measuring regional salivary gland function after radiotherapy of head and neck cancer

    International Nuclear Information System (INIS)

    Buus, Simon; Grau, Cai; Munk, Ole Lajord; Bender, Dirk; Jensen, Kenneth; Keiding, Susanne

    2004-01-01

    Background and purpose: Loss of salivary gland function is a distressing side-effect of radiotherapy (RT) for head and neck cancer. The aim of this study was to develop a positron emission tomography (PET) method for measuring regional salivary gland function in the major salivary glands irradiated during RT. Patients and methods: Eight head and neck cancer patients were included; two were examined before RT and six after parotid sparing RT. Patients were examined by dynamic 11 C-methionine PET of the major salivary glands and parotid gland salivary flow measurements. PET data were analysed using a kinetic model of salivary gland 11 C-methionine metabolism, in which salivary gland function was quantified by the net metabolic clearance of 11 C-methionine, K. Functional voxel-wise images of K were calculated and matched with the CT-dose-plan for comparing regional salivary gland function with the regional radiation dose. Results: Parotid gland K correlated positively with parotid gland salivary flow, indicating that K can be used as an index of salivary gland function. K of parotid and submandibular glands was reduced dependent on the median radiation dose. In one patient, receiving a heterogeneous radiation dose to the parotid glands, regional salivary gland function was inversely correlated to the regional radiation dose. Conclusions: Salivary gland function can be measured by dynamic 11 C-methionine PET. The net metabolic clearance of 11 C-methionine of salivary glands was reduced dependent on the radiation dose. Dynamic 11 C-methionine PET offers a method for studying the individual response of the major salivary glands to irradiation

  19. Design, construction and performance evaluation of the target tissue thickness measurement system in intraoperative radiotherapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yazdani, Mohammad Reza, E-mail: myazdani@aut.ac.ir [Faculty of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Setayeshi, Saeed, E-mail: setayesh@aut.ac.ir [Faculty of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Arabalibeik, Hossein, E-mail: arabalibeik@tums.ac.ir [Research Center for Biomedical Technology and Robotics (RCBTR), Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Akbari, Mohammad Esmaeil [Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2017-05-21

    Intraoperative electron radiation therapy (IOERT), which uses electron beams for irradiating the target directly during the surgery, has the advantage of delivering a homogeneous dose to a controlled layer of tissue. Since the dose falls off quickly below the target thickness, the underlying normal tissues are spared. In selecting the appropriate electron energy, the accuracy of the target tissue thickness measurement is critical. In contrast to other procedures applied in IOERT, the routine measurement method is considered to be completely traditional and approximate. In this work, a novel mechanism is proposed for measuring the target tissue thickness with an acceptable level of accuracy. An electronic system has been designed and manufactured with the capability of measuring the tissue thickness based on the recorded electron density under the target. The results indicated the possibility of thickness measurement with a maximum error of 2 mm for 91.35% of data. Aside from system limitation in estimating the thickness of 5 mm phantom, for 88.94% of data, maximum error is 1 mm.

  20. Design, construction and performance evaluation of the target tissue thickness measurement system in intraoperative radiotherapy for breast cancer

    Science.gov (United States)

    Yazdani, Mohammad Reza; Setayeshi, Saeed; Arabalibeik, Hossein; Akbari, Mohammad Esmaeil

    2017-05-01

    Intraoperative electron radiation therapy (IOERT), which uses electron beams for irradiating the target directly during the surgery, has the advantage of delivering a homogeneous dose to a controlled layer of tissue. Since the dose falls off quickly below the target thickness, the underlying normal tissues are spared. In selecting the appropriate electron energy, the accuracy of the target tissue thickness measurement is critical. In contrast to other procedures applied in IOERT, the routine measurement method is considered to be completely traditional and approximate. In this work, a novel mechanism is proposed for measuring the target tissue thickness with an acceptable level of accuracy. An electronic system has been designed and manufactured with the capability of measuring the tissue thickness based on the recorded electron density under the target. The results indicated the possibility of thickness measurement with a maximum error of 2 mm for 91.35% of data. Aside from system limitation in estimating the thickness of 5 mm phantom, for 88.94% of data, maximum error is 1 mm.

  1. Quality assurance in radiotherapy

    International Nuclear Information System (INIS)

    Tripathi, U.B.

    1998-01-01

    Quality assurance in radiotherapy embodies in itself all those procedures that ensure consistency of the clinical prescription and correct fulfillment of that prescription as regards to dose to the target volume, together with minimal dose to the normal tissue, minimal exposure to the occupational workers and adequate patient monitoring aimed at determining the end result of the treatment. This definition aptly describes the role of quality assurance (QA) in radiotherapy practice. QA needs for different systems and sub-systems of the equipment, dose measuring equipment and techniques, dose delivery methodologies, treatment planning system, plan evaluation, follow-up etc. It should clearly define the tolerance limits, action and intervention levels and test frequencies for different test parameters. This paper will dwell on some of these topics in some detail while only passing references will be made to others. Rationale for tolerance limits and test frequencies will be discussed. Attention will also be focussed on the definitions and implementations of the action and intervention levels

  2. Production of a pion in association with a high-Q2 dilepton pair in antiproton-proton annihilation at GSI-FAIR

    International Nuclear Information System (INIS)

    Lansberg, J. P.; Pire, B.; Szymanowski, L.

    2007-01-01

    We evaluate the cross section for pp→l + l - π 0 in the forward direction and for a large lepton pair invariant mass. In this kinematical region, the leading-twist amplitude factorizes into a short-distance matrix element, long-distance antiproton-distribution amplitudes, and proton to pion transition distribution amplitudes (TDAs). Using a modeling inspired from the chiral limit for these TDAs, we obtain a first estimate of this cross section, which demonstrates that this process can be measured at GSI-FAIR

  3. Predictors for trismus in patients receiving radiotherapy.

    Science.gov (United States)

    van der Geer, S Joyce; Kamstra, Jolanda I; Roodenburg, Jan L N; van Leeuwen, Marianne; Reintsema, Harry; Langendijk, Johannes A; Dijkstra, Pieter U

    2016-11-01

    Trismus, a restricted mouth opening in head and neck cancer patients may be caused by tumor infiltration in masticatory muscles, radiation-induced fibrosis or scarring after surgery. It may impede oral functioning severely. The aims of our study were to determine: (1) the incidence of trismus at various time points; and (2) the patient, tumor, and treatment characteristics that predict the development of trismus after radiotherapy in head and neck cancer patients using a large database (n = 641). Maximal mouth opening was measured prior to and 6, 12, 18, 24, 36, and 48 months after radiotherapy. Patient, tumor, and treatment characteristics were analyzed as potential predictors for trismus using a multivariable logistic regression analysis. At six months after radiotherapy, 28.1% of the patients without trismus prior to radiotherapy developed trismus for the first time. At subsequent time points the incidence declined. Over a total period of 48 months after radiotherapy, the incidence of trismus was 3.6 per 10 person years at risk. Patients who had tumors located in the oral cavity, oropharynx or nasopharynx, and the salivary glands or ear, and who had a longer overall treatment time of radiotherapy, were more likely to develop trismus in the first six months after radiotherapy. Maximal mouth opening was a predictor for developing trismus at all time points. Incidence of trismus is 3.6 per 10 person years at risk. Tumor localization and overall treatment time of radiotherapy are predictors for developing trismus the first six months after radiotherapy. Maximal mouth opening is a significant predictor for developing trismus at all time points. Regular measurements of maximal mouth opening are needed to predict trismus.

  4. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    In radiotherapy, the primary objective is to deliver a prescribed dose of radiation to a tumour or lesion within a patient while minimising the dose delivered to the surrounding healthy tissue. Traditional radiotherapy treatments usually involve simple external or internal irradiations of a tumour. External irradiations are normally achieved in the clinic with photon or electron beams produced by high energy linear accelerators. The photon or electron beams are collimated into regular shapes as they emerge from the treatment head of the unit which is supported by a gantry that can be rotated isocentrically to any position. A discrete number of photon or electron beams with different angles of incidence that intersect at the iso-centre are used to produce a region of high dose around the tumour volume (positioned at the iso-centre). Internal irradiations are normally achieved in the clinic by implanting radioactive sources in and around the tumour or lesion. Such irradiations are characterised by very high doses local to the tumour. Radioactive sources are also used to prevent post-angioplasty restenosis by inserting sources into arteries. Usually when treating a tumour, a compromise is made between tumour control and complications arising from normal tissue damage. One measure of this compromise, the therapeutic ratio, is defined as the radiation dose producing complications in 50% of patients divided by the dose providing tumour control in 50% of the patients. The therapeutic ratio depends on the radiobiological characteristics of the cancerous tissue and surrounding healthy tissues and on the radiation dose distribution achieved by the radiotherapy treatment. It is generally believed that the therapeutic ratio can be minimised by optimising the conformation of the radiation dose distribution to the target volume. This is difficult with traditional radiotherapy techniques since they do not produce dose distributions that adequately cover tumour volumes of complex

  5. Proton and antiproton interactions in hydrogen, argon and xenon at 200 GeV

    International Nuclear Information System (INIS)

    Malecki, P.

    1984-01-01

    The detailed analysis of the production of particles emitted into forward hemisphere in 200 GeV proton and antiproton interactions with hydrogen, argon and xenon targets is presented. Two-particle rapidity correlations and long-range multiplicity correlations are also discussed. (author)

  6. A study of Two Photon Decays of Charmonium Resonances Formed in Proton Anti-Proton Annihilations

    Energy Technology Data Exchange (ETDEWEB)

    Pedlar, Todd Kristofer [Northwestern Univ., Evanston, IL (United States)

    1999-06-01

    In this dissertation we describe the results of an investigation of the production of charmonium states (ηc, η'c, χ0 and χ2) in Fermilab experiment E835 via antiproton-proton annihilation and their detection via their decay into two photons.

  7. Antiproton signatures from astrophysical and dark matter sources at the galactic center

    Energy Technology Data Exchange (ETDEWEB)

    Cembranos, J.A.R.; Gammaldi, V.; Maroto, A.L., E-mail: cembra@ucm.es, E-mail: vivigamm@ucm.es, E-mail: maroto@fis.ucm.es [Departamento de Física Teórica I, Facultad Ciencias Físicas, Universidad Complutense Madrid, Ciudad Universitaria, E-28040 Madrid (Spain)

    2015-03-01

    The center of our Galaxy is a complex region characterized by extreme phenomena. The presence of the supermassive Sagittarius A* black hole, a high dark matter density and an even higher baryonic density are able to produce very energetic processes. Indeed, high energetic gamma-rays have been observed by different telescopes, although their origin is not clear. In this work, we estimate the possible antiproton flux component associated with this signal. The expected secondary astrophysical antiproton background already saturates the observed data. It implies that any other important astrophysical source leads to an inconsistent excess. We estimate the sensitivity of PAMELA to this new primary antiproton source, which depends on the diffusion model and its spectral features. In particular, we consider antiproton spectra described by a power-law, a monochromatic signal and a Standard Model particle-antiparticle channel production. This latter spectrum is typical in the production from annihilating or decaying dark matter. We pay particular attention to the case of a heavy dark matter candidate, which could be associated with the High Energy Stereoscopic System (HESS) data observed from the J1745-290 source.

  8. Properties of Antiprotons and Antihydrogen, and the Study of Exotic Atoms

    CERN Document Server

    Doser, Michael

    2015-01-01

    The study of exotic atoms, of antiprotons and of antihydrogen atoms provides many windows into the investigation of fundamental symmetries, of interactions between particles and nuclei, of nuclear physics and of atomic physics. This field appeared at CERN simultaneously with the first accelerators, and has advanced over the decades in parallel with improvements and advances in its infrastructure.

  9. Antiproton and proton collisions with the alkali-metal atoms Li, Na, and K

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2008-01-01

    Single-electron ionization and excitation cross sections as well as cross sections for excitation into the first excited p state of the alkali-metal atoms Li(2s), Na(3s), and K(4s) colliding with antiprotons and protons were calculated using a time-dependent channel-coupling approach. For antipro...

  10. S142 set-up to detect X-ray from antiproton-proton atoms (protonium).

    CERN Multimedia

    1978-01-01

    This experiment was designed by the Daresbury-Mainz-TRIUMF Collaboration and was located in the m14 partially separated antiproton beam in the PS South Hall. It used a gaseous hydrogen target, 1 m long, surrounded by a ring of proportional counters, surrounded in turn by a ring of 36 scintillators strips to aid in the annihilation product identification. Ugo Gastaldi (centre)

  11. Full two-electron calculations of antiproton collisions with molecular hydrogen

    DEFF Research Database (Denmark)

    Lühr, Armin Christian; Saenz, Alejandro

    2010-01-01

    Total cross sections for single ionization and excitation of molecular hydrogen by antiproton impact are presented over a wide range of impact energies from 1 keV to 6.5 MeV. A nonperturbative time-dependent close-coupling method is applied to fully treat the correlated dynamics of the electrons....

  12. Gonad doses in radiotherapy. Phantom measurement in mammary carcinomas, Morbus Hodgkin, seminomas, hypernephromas, and rhabdomyosarcomas of the thigh

    International Nuclear Information System (INIS)

    Liebstueckel, L.

    1979-01-01

    The gonad doses in the therapy of malignant diseases were determined under defined conditions with the aid of a 60 Co and a 137 Cs irradiation appliance using an Alderson and paraffin phantom each. The measurements were carried out with a condiometer by Physikalisch-Technische Werkstaetten, Freiburg. Two different types of condensator chambers with a measuring range 15 mR to 8 R were used. In the irradiation of mammary carcinoma using the Alderson phantom with two tangential stationary fields the ovarian dose was 0.49 to 1.05 per mille, the testicular dose 0.3 to 0.47 per mille of the maximum irradiated dose. If mammary carcinomas are irradiated using a Caesa-Gammatron, the ovarian dose varies from 0.04 to 0.78 per mille within the five fields, the testicular dose from 0.01 to 0.13 per mille. For these measurements the paraffin phantom was used. If the radiation technique was somewhat modified, the ovaries (testes) of the Alderson phantom irradiated for Hodgkin's disease received 7 (4.7) per mille from irradiation of the thoracal field and 4.6 (3.2) per mille from irradiation of the mediastinal field. Irradiation of the abdominal field produced doses for the female and male gonads of 520 resp. 47.2 per mille. On irradiation of the para-aortic field, the ovaries and testes received doses of 8 resp. 4.6 per mille. Irradiation of the Alderson phantom for seminoma involved testicular doses between 29.1 and 3.1 per mille, depending on the size of the field and its distance from the gonads. Hypernephroma irradiation was carried out on the Alderson phantom with two pendular fields. The ovaries received between 3.7 and 14 per mille and the testes between 2.3 and 3.3 per mille of the focal dose. In irradiation for rhabdomyosarcoma, simulated with the paraffin phantom, the ovarian doses ranged between 5.5 and 11.9 per mille. The male gonad dose rose to values between 36.5 and 458 per mille of the focal dose. (orig./MG) [de

  13. Radiation Pneumonitis after Radiotherapy of Neck Lymphoma

    OpenAIRE

    Wei, Min; Cai, Jun; Tong, Tao; Yu, Shihua; Yang, Yonghua; Zhang, Weijia; Yang, Jiyuan

    2014-01-01

    Radiotherapy is still one of the effective means for treatment of malignant tumors up to now. Particularly, it is an indispensable effective measure for treatment of some lymphoma patients. In routine work, radiation pneumonitis (RP) is the most significant complication of acute treatment-related toxicities in lung cancer; however, serious radioactive pneumonia is rare for the radiotherapy of neck lymphoma because the volume of the lungs affected by radiation dose was very small. We report a ...

  14. Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p–Pb collisions at sNN=5.02 TeV

    NARCIS (Netherlands)

    Peitzmann, T.; Grelli, A.; Snellings, R.J.M.; Mischke, A.; Bertens, R.A.; Keijdener, D.L.D.

    2016-01-01

    The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity (−0.5

  15. Anatomical imaging for radiotherapy

    International Nuclear Information System (INIS)

    Evans, Philip M

    2008-01-01

    The goal of radiation therapy is to achieve maximal therapeutic benefit expressed in terms of a high probability of local control of disease with minimal side effects. Physically this often equates to the delivery of a high dose of radiation to the tumour or target region whilst maintaining an acceptably low dose to other tissues, particularly those adjacent to the target. Techniques such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery and computer planned brachytherapy provide the means to calculate the radiation dose delivery to achieve the desired dose distribution. Imaging is an essential tool in all state of the art planning and delivery techniques: (i) to enable planning of the desired treatment, (ii) to verify the treatment is delivered as planned and (iii) to follow-up treatment outcome to monitor that the treatment has had the desired effect. Clinical imaging techniques can be loosely classified into anatomic methods which measure the basic physical characteristics of tissue such as their density and biological imaging techniques which measure functional characteristics such as metabolism. In this review we consider anatomical imaging techniques. Biological imaging is considered in another article. Anatomical imaging is generally used for goals (i) and (ii) above. Computed tomography (CT) has been the mainstay of anatomical treatment planning for many years, enabling some delineation of soft tissue as well as radiation attenuation estimation for dose prediction. Magnetic resonance imaging is fast becoming widespread alongside CT, enabling superior soft-tissue visualization. Traditionally scanning for treatment planning has relied on the use of a single snapshot scan. Recent years have seen the development of techniques such as 4D CT and adaptive radiotherapy (ART). In 4D CT raw data are encoded with phase information and reconstructed to yield a set of scans detailing motion through the breathing, or cardiac, cycle. In ART a set of

  16. Photoneutron Flux Measurement via Neutron Activation Analysis in a Radiotherapy Bunker with an 18 MV Linear Accelerator

    Directory of Open Access Journals (Sweden)

    Çeçen Yiğit

    2017-01-01

    Full Text Available In cancer treatment, high energy X-rays are used which are produced by linear accelerators (LINACs. If the energy of these beams is over 8 MeV, photonuclear reactions occur between the bremsstrahlung photons and the metallic parts of the LINAC. As a result of these interactions, neutrons are also produced as secondary radiation products (γ,n which are called photoneutrons. The study aims to map the photoneutron flux distribution within the LINAC bunker via neutron activation analysis (NAA using indium-cadmium foils. Irradiations made at different gantry angles (0°, 90°, 180° and 270° with a total of 91 positions in the Philips SLI-25 linear accelerator treatment room and location-based distribution of thermal neutron flux was obtained. Gamma spectrum analysis was carried out with high purity germanium (HPGe detector. Results of the analysis showed that the maximum neutron flux in the room occurred at just above of the LINAC head (1.2x105 neutrons/cm2.s which is compatible with an americium-beryllium (Am-Be neutron source. There was a 90% decrease of flux at the walls and at the start of the maze with respect to the maximum neutron flux. And, just in front of the LINAC door, inside the room, neutron flux was measured less than 1% of the maximum.

  17. Quality Assurance in Radiotherapy

    Science.gov (United States)

    Mckenzie, Alan

    A common feature of the Radiotherapy Centres where there have been major accidents involving incorrect radiotherapy treatment is that they did not operate good Quality Assurance systems. A Quality Assurance system is sometimes called a Quality Management system, and it is designed to give assurance that quality standards are being met. One of the "spin offs" from operating a Quality Management system is that it reduces the likelihood of a radiotherapy accident. A detailed account of how to set up a quality system in radiotherapy has been given in an ESTRO booklet.2

  18. Radiotherapy in small countries.

    Science.gov (United States)

    Barton, Michael B; Zubizarreta, Eduardo H; Polo Rubio, J Alfredo

    2017-10-01

    To examine the availability of radiotherapy in small countries. A small country was defined as a country with a population less than one million persons. The economic status of each country was defined using the World Bank Classification. The number of cancers in each country was obtained from GLOBOCAN 2012. The number of cancer cases with an indication or radiotherapy was calculated using the CCORE model. There were 41 countries with a population of under 1 million; 15 were classified as High Income, 15 Upper Middle Income, 10 Lower Middle Income and one Low Income. 28 countries were islands. Populations ranged from 799 (Holy See) to 886450 (Fiji) and the total number of cancer cases occurring in small countries was 21,043 (range by country from 4 to 2476). Overall the total number of radiotherapy cases in small countries was 10982 (range by country from 2 to 1239). Radiotherapy was available in all HIC islands with 80 or more new cases of cancer in 2012 but was not available in any LMIC island. Fiji was the only LMIC island with a large radiotherapy caseload. Similar caseloads in non-island LMIC all had radiotherapy services. Most non-island HIC did not have radiotherapy services presumably because of the easy access to radiotherapy in neighbouring countries. There are no radiotherapy services in any LMIC islands. Copyright © 2017. Published by Elsevier Ltd.

  19. [Radiotherapy during pregnancy].

    Science.gov (United States)

    Mazeron, R; Barillot, I; Mornex, F; Giraud, P

    2016-09-01

    The diagnostic of cancer during pregnancy is a rare and delicate situation. As the developments of the embryo and the human fetus are extremely sensitive to ionizing radiations, the treatment of these tumors should be discussed. The studies - preclinical and clinical - based mostly on exposure accidents show that subdiaphragmatic treatments are possible during pregnancy. When radiotherapy is used, phantom estimations of the dose to the fetus, confirmed by in vivo measurements are required. Irradiation and imaging techniques should be arranged to decrease as much as possible the dose delivered to the fetus and hold below the threshold of 0.1Gy. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  20. A systematic review of the precision and accuracy of dose measurements in photon radiotherapy using polymer and Fricke MRI gel dosimetry

    International Nuclear Information System (INIS)

    MacDougall, N.D.; Pitchford, W.G.; Smith, M.A.

    2002-01-01

    1998 Radiother. Oncol. 48 283-91, Farajollahi et al 2000 Br. J. Radiol. 72 1085-92, McJury et al 1999b Phys. Med. Biol. 44 2431-44, Murphy et al 2000b Phys. Med. Biol. 45 835-45, Oldham et al 2001 Med. Phys. 28 1436-45) and 5% for Fricke gel (Chan and Ayyangar 1995b Med. Phys. 22 1171-5). Evidence also points to accuracy worsening at lower dose levels for both gels. The precision data should be viewed with caution as repeated MR measurements were not performed with the same samples. The only precision data for Fricke gels was 1.5% (Johansson Back et al 1998 Phys. Med. Biol. 43 261-76), but for zero dose. In conclusion, despite the amount of published data, sparse research has been undertaken which provides clear evidence of the accuracy and precision for both gels. That which has been published has used higher doses than would be routine in radiotherapy. The basic radiation dosimeter qualities of accuracy and precision have yet to be fully quantified for polymer and Fricke gels at clinically relevant dose levels. (author)