WorldWideScience

Sample records for pion generator for medical irradiations

  1. PIGMI: a design report for Pion Generator for Medical Irradiations

    International Nuclear Information System (INIS)

    Hansborough, L.D.

    1981-09-01

    PIGMI (Pion Generator for Medical Irradiations) is an integrated linear accelerator (linac) system developed under the auspices of the National Cancer Institute for specific application to cancer treatment in a hospital environment. In its full configuration, PIGMI is a proton linac that is far smaller, less expensive, and more reliable than previous machines that produce pions. Subsets of PIGMI technology can be used with equal advantage to generate beams of other particles (such as neutrons, protons, or heavy ions) that may be of interest for radiotherapy, radioisotope production, or other applications. The dramatic performance and cost advantages of this new breed of acceleraor result from a number of improvements. In the low-energy portion of the machine, a new type of low-energy linac (the radio-frequency quadrupole[RFQ]) produces an exceptionally good quality beam, and uses a very simple 30-kV injector. In the second part of the machine (the drift-tube linac [DTL]), high accelerating gradients are now achievable with consequent reductions in machine length. Another new structure (the disk and washer [DAW]) will be used in the third and final section of the accelerator; this portion will also be relatively short and require few power amplifiers. The entire machine is designed for ease of operation and high reliability. The pion-production machine, discussed in this report, accelerates a 100-μA average proton-beam current to 650 MeV; use of an efficient pion-collection channel would result in an average pion flux of over 100 rad/min in a volume of about 1 l. Pion-channel design is not treated in this report. Accelerator construction cost is estimated at $10 million (1980 dollars); site preparation and treatment facility costs would bring the cost of a complete facility to an estimated $25 million

  2. Basic considerations in simulated treatment planning for the Stanford Medical Pion Generator (SMPG)

    International Nuclear Information System (INIS)

    Pistenma, D.A.; Li, G.C.; Bagshaw, M.A.

    1977-01-01

    Recent interest in charged heavy particle irradiation is based upon expected improved local tumor control rates because of the greater precision in dose localization and the increased biological effectiveness of the high linear energy transfer ionization of particle beams in their stopping regions (Bragg peaks). A novel 60 beam cylindrical geometry pion spectrometer designed for a hospital-based pion therapy facility has been constructed at Stanford. In conjunction with the development and testing of the SMPG a program of simulated treatment planning is being conducted. This paper presents basic considerations in treatment planning for pions and other charged heavy particles. It also presents the status of simulated treatment planning calculations for the SMPG including a discussion of the principle of irradiation of hypothetical tumor volumes illustrated by examples of simplified treatment plans incorporating tissue density inhomogeneity corrections. Also presented are considerations for realistic simulated treatment planning calculations using computerized tomographic scan cross sections of actual patients and a conceptual plan for an integrated treatment planning and patient treatment system for the SMPG

  3. Negative pion irradiation of mammalian cells

    International Nuclear Information System (INIS)

    Dertinger, H.; Luecke-Huhle, C.; Schlag, H.; Weibezahn, K.F.

    1976-01-01

    Monolayers and spheroids of Chinese hamster cells (V79) were subjected to negative pion irradiation under aerobic conditions. R.b.e. values in the pion peak of 1.8 and 1.5 were obtained for monolayers and spheroids, respectively, whereas the r.b.e. for the plateau was found to be slightly higher than 1. In addition, it was observed that the higher resistance of the V79 spheroid cells than the monolayers to γ-irradiation is not diminished in the pion peak, suggesting that the underlying phenomenon of intercellular communication influences cell survival even after high-LET irradiation. (author)

  4. Electron linac design for pion radiotherapy

    International Nuclear Information System (INIS)

    Loew, G.A.; Brown, K.L.; Miller, R.H.; Walz, D.R.

    1977-03-01

    The electron linac provides a straightforward, state-of-the-art method of producing the primary beam required for a hospital-based multiport pion radiotherapy facility for cancer treatment. The accelerator and associated beam transport system described are capable of generating an electron beam of about 250 kW and delivering it alternately to one of several pion generators and treatment areas. Each pion generator, a prototype of which now exists at the Stanford W. W. Hansen Laboratory, would contain a target for the electron beam and sixty separate superconducting magnet channels which focus the pions in the patient. The considerations which enter the design of a practical linac are presented together with a possible layout of a flexible beam transport system

  5. Some long-term effects of negative pions in mice exposed to partial body irradiation

    International Nuclear Information System (INIS)

    Coggle, J.E.

    1977-01-01

    The long-term effects of partial body exposure of one-day-old mice given either 60 Co γ rays or negative pions have been studied. Both radiations produced considerable life-shortening; for pions 6.8 +- 1.5% of life was lost per 100 rad and for γ rays the value was 5.7 +- 0.5% per 100 rad. The RBE of pions for ten weeks of life-shortening was about 1.3 compared with 60 Co γ rays, although at lower doses the RBE may be higher reaching about two for six weeks of life-shortening. The incidence rate of tumours at any particular age was greater in mice irradiated with pions at the peak and in those given higher doses of γ rays than in the controls. (author)

  6. Pion interferometry theory for the hydrodynamic stage of multiple processes

    International Nuclear Information System (INIS)

    Makhlin, A.N.; Sinyukov, Yu.M.

    1986-01-01

    The double pion inclusive cross section for identical particles is described in hydrodynamical theory of multiparticle production. The pion interferometry theory is developed for the case when secondary particles are generated against the background of internal relativistic motion of radiative hadron matter. The connection between correlation functions in various schemes of experiment is found within the framework of relativistic Wigner functions formalism

  7. Investigations in the problem of pion condensation using generator co-ordinate methods

    International Nuclear Information System (INIS)

    Chattopadhyay, P.; Providencia, J. da

    1981-01-01

    Pion condensation in neutron matter has been investigated using the generator coordinate methode and a simple p-wave interaction. The assumption of a condensed mode corresponding to one pion momentum (determined variationally) helps evaluate all the necessary matrix elements exactly. The technique of charge projection from a coherent state of negative pions is discussed, and calculations have been carried out for the cases of average charge conversation, charge projection before variation and for a charge conserving trial function. The ground-state energies and the lowest excitations of the system are obtained from numerical solutions of the Hill-Wheeler equation. (orig.)

  8. Coherent and chaotic generation of pions from relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Nakamura, Hiroki; Seki, Ryoichi

    2002-01-01

    Based on the recent NA44 and WA98 two- and three-pion interferometry data together with the WA98 pion multiplicity information, we observe that the pions may be mostly emitted from chaotic sources in the peripheral events and coherent pions are mostly generated in the central events. A more refined analysis would be needed, however, to make our observation conclusive by quantifying various effects such as resonance formation of the emerging pions and also experimental uncertainties

  9. Comparison of pad detectors produced on different silicon materials after irradiation with neutrons, protons and pions

    International Nuclear Information System (INIS)

    Kramberger, G.; Cindro, V.; Dolenc, I.; Mandic, I.; Mikuz, M.; Zavrtanik, M.

    2010-01-01

    A set of 44 pad detectors produced on p- and n-type MCz and Fz wafers was irradiated with 23 GeV protons, 200 MeV pions and reactor neutrons up to the equivalent fluences of Φ eq =3x10 15 cm -2 . The evolution of the full depletion voltage and the leakage current were monitored during short- and long-term annealing. At selected representative annealing steps, charge collection measurements were performed for all samples with LHC speed electronics. Measurements of full depletion voltage, leakage current and charge collection efficiency were compared for different irradiation particles and silicon materials.

  10. Comparison of pad detectors produced on different silicon materials after irradiation with neutrons, protons and pions

    Energy Technology Data Exchange (ETDEWEB)

    Kramberger, G., E-mail: Gregor.Kramberger@ijs.s [Jozef Stefan Institute and Department of Physics, University of Ljubljana, SI-1000 Ljubljana (Slovenia); Cindro, V.; Dolenc, I.; Mandic, I.; Mikuz, M.; Zavrtanik, M. [Jozef Stefan Institute and Department of Physics, University of Ljubljana, SI-1000 Ljubljana (Slovenia)

    2010-01-01

    A set of 44 pad detectors produced on p- and n-type MCz and Fz wafers was irradiated with 23 GeV protons, 200 MeV pions and reactor neutrons up to the equivalent fluences of PHI{sub eq}=3x10{sup 15}cm{sup -2}. The evolution of the full depletion voltage and the leakage current were monitored during short- and long-term annealing. At selected representative annealing steps, charge collection measurements were performed for all samples with LHC speed electronics. Measurements of full depletion voltage, leakage current and charge collection efficiency were compared for different irradiation particles and silicon materials.

  11. Design experiences for medical irradiation field at the musashi reactor

    International Nuclear Information System (INIS)

    Aizawa, Otohiko

    1994-01-01

    The design of the medical irradiation field at the Musashi reactor was carried out from 1974 to 1975, about 20 years ago. Various numerical analyses have been carried out recently, and it is astonishing to find out that the performance close to the optimum as a 100 kW reactor has been obtained. The reason for this is that the design was carried out by dividing into the stationary part and the moving part, and as for the moving part, the structure was determined by repeating trial and error and experiments. In this paper, the comparison of the analysis carried out later with the experimental data and the change of the absorbed dose at the time of medical irradiation accompanying the change of neutron energy spectra are reported. As the characteristics of the medical irradiation field at the Musashi reactor, the neutron energy spectra and the absorbed dose and mean medical irradiation time are shown. As the problems in boron neutron capture therapy, the neutron fluence required for the therapy, the way of thinking on background dose, and the problem of determining the irradiation time are discussed. The features of epithermal neutron beam are explained. (K.I.)

  12. Radiation tolerance of CVD diamond detectors for pions and protons

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F. E-mail: f.hartjes@nikhef.nl; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M

    2002-01-11

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/c pions and 24 GeV/c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal.

  13. Radiation tolerance of CVD diamond detectors for pions and protons

    Science.gov (United States)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L. S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J. L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R. J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.

    2002-01-01

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/ c pions and 24 GeV/ c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal.

  14. Radiation tolerance of CVD diamond detectors for pions and protons

    International Nuclear Information System (INIS)

    Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.

    2002-01-01

    The paper gives new results on the radiation tolerance of CVD diamond for irradiation with 300 MeV/c pions and 24 GeV/c protons. The measured charge signal spectrum is compared at several irradiation levels with the spectrum calculated by a model. Irradiation by particles causes damage leading to a decrease of the charge signal. However, both the measurements and the outcome from the model show that for tracker applications this drawback is at least partly counterbalanced by a narrowing of the distribution curve of the charge signal. As a result, the efficiency of a CVD diamond tracker is less affected by irradiation than the mean charge signal

  15. Effects of tissue inhomogeneities on dose patterns in cylinders irradiated by negative pion beams

    International Nuclear Information System (INIS)

    Hamm, R.N.; Wright, H.A.; Turner, J.E.

    1975-10-01

    Effects of the presence of inhomogeneities in tissue irradiated by negative pion beams are investigated. Soft-tissue targets are considered with embedded regions of bone and cavities of air. The absorbed dose is calculated as a function of position in the targets for parallel and converging beams and for two parallel beams that enter the target from opposite sides. Isodose contours are calculated and displayed in each case. While these studies show expected trends, they indicate that specific calculations are needed for other beam parameters and target geometries. The contributions of neutrons to the dose contours can be seen from several calculations made both with and without neutrons

  16. Chiral pion dynamics for spherical nucleon bags

    International Nuclear Information System (INIS)

    Vento, V.; Rho, M.; Nyman, E.M.; Jun, J.H.; Brown, G.E.; CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette

    1980-01-01

    A chirally symmetric quark-bag model for the nucleon is obtained by introducing an explicit, classical, pion field exterior to the bag. The coupling at the bag surface is determined by the requirement of a conserved axial-vector current. The pion field satisfies equations of motion corresponding to the non-linear sigma-model. We study on this paper the simplified case where the bag and the pion field are spherically symmetric. Corrections due to gluon exchange between the quarks are ignored along with other interactions which split the N- and Δ-masses. The equations of motion for the pion field are solved and we find a substantial pion pressure at the bag surface, along with an attractive contribution to the nucleon self-energy. The total energy of the system, bag plus meson cloud, turns out to be approximately Msub(n)c 2 for a wide range of bag radii, from 1.5 fm down to about 0.5 fm. Introduction of a form factor for the pion would extend the range of possible radii to even smaller values. We propose that the bag with the smallest allowed radius be identified with the 'little bag' discussed before. One surprising result of the paper is that as long as one restricts to spherically symmetric bags, restoring chiral symmetry to the bag model makes the axial-vector current coupling constant gsub(A) to be always too large compared with the experimental value for any bag radius, suggesting a deviation from spherical symmetry for the intrinsic bag wave functions of the 'ground-state' hadrons. (orig.)

  17. Low-energy photo- and electroproduction for physical pions

    International Nuclear Information System (INIS)

    MacMullen, J.T.

    1979-02-01

    The Ward identities of current algebra are combined with gauge invariance constraints, on-shell PCAC and the Bjorken limit to obtain the low-energy expressions of the pion photo- and electroproduction invariant amplitudes for physical pions

  18. Synthetic study of reactor irradiation for medical use

    International Nuclear Information System (INIS)

    An, Shigehiro; Furuhashi, Akira; Kanda, Keiji; Sumita, Kenji; Kakihana, Hidetake.

    1978-01-01

    This report is described on the results of the study on the reactor irradiation for medical use shared by the Nuclear Engineering Research Laboratory, Faculty of Engineering, University of Tokyo, and other seventeen facilities. Boron neutron-capturing therapy developed in Japan is extremely significant treating method for tumors by destroying tumor cells of encephaloma, etc. selectively. This is the synthetic study for promoting the above therapeutic method. Two existing reactors were reconstructed into the thermal neutron reactors for boron neutron-capturing therapy. The various preparatory and physical researches were made with the reconstruction, and the therapy was tried on eleven cases. Further experiments were made on the following points: (1) To promote treatment on encephaloma by boron neutron-capturing therapy. (2) To develop its application to malignant tumors other than encephaloma. (3) Animal irradiation experiments. (4) The basic experiments on the cellular level. (5) The study of remote controlled anesthesia. (6) To control irradiated dose. (7) To improve boron compounds. (8) To condense radioisotopes. (Kobatake, H.)

  19. Knock out for subthreshold pion production

    International Nuclear Information System (INIS)

    Guet, C.; Prakash, M.

    1984-05-01

    The contribution of nucleon-nucleon-single collisions to subthreshold pion production in hadron-nucleus and nucleus-nucleus collisions, Esub(Lab) < 300 A MeV is investigated within a knock-out type model. This contribution might be important for energies higher than about 150 MeV/nucleon but decrease strongly with decreasing beam energy

  20. Pion, pion-pion, and pion-nucleus interactions

    CERN Document Server

    Mukhin, K N; Tikhonov, V N

    2002-01-01

    This survey is devoted to describing the early studies of 1.1. Gurevich on pion physics that were performed by the photoemulsion method and the studies of the pion-pion interaction that were made by his colleagues on the basis of the hydrogen-bubble-chamber and the magnetic-spectrometer method (as well-as on the basis of the photoemulsion method). Two approaches-an extrapolation of experimental data from the physical region to the pion pole and a theoretical calculation based on the Roy integral equations-are used to deduce information about the pion-pion interaction. The first results obtained for pion-pion and pion-nucleus interactions in the experiments that are being currently performed in Brookhaven and at CERN ( pi pi interaction) and at TRIUMF (Canada) and in Brookhaven (pion-nucleus interaction) are presented, along with the existing theoretical concepts in these realms of physics. (80 refs).

  1. Signal height in silicon pixel detectors irradiated with pions and protons

    International Nuclear Information System (INIS)

    Rohe, T.; Acosta, J.; Bean, A.; Dambach, S.; Erdmann, W.; Langenegger, U.; Martin, C.; Meier, B.; Radicci, V.; Sibille, J.; Trueb, P.

    2010-01-01

    Pixel detectors are used in the innermost part of multi-purpose experiments at the Large Hadron Collider (LHC) and are therefore exposed to the highest fluences of ionising radiation, which in this part of the detectors consists mainly of charged pions. The radiation hardness of the detectors has been tested thoroughly up to the fluences expected at the LHC. In case of an LHC upgrade the fluence will be much higher and it is not yet clear up to which radii the present pixel technology can be used. To establish such a limit, pixel sensors of the size of one CMS pixel readout chip (PSI46V2.1) have been bump bonded and irradiated with positive pions up to 6x10 14 n eq /cm 2 at PSI and with protons up to 5x10 15 n eq /cm 2 . The sensors were taken from production wafers of the CMS barrel pixel detector. They use n-type DOFZ material with a resistance of about 3.7kΩcm and an n-side read out. As the performance of silicon sensors is limited by trapping, the response to a Sr-90 source was investigated. The highly energetic beta-particles represent a good approximation to minimum ionising particles. The bias dependence of the signal for a wide range of fluences will be presented.

  2. Gamma irradiation for food preservation and sterilization of medical supplies

    International Nuclear Information System (INIS)

    Syed Abid Husain; Mohammad Said Kadis

    1981-01-01

    A new technology in food preservation by using gamma irradiation was introduced and its advantages over a number of conventional processes were discussed. The new technique is also applicable in the sterilization of medical supplies. It is relatively simple and does not require very highly skilled manpower

  3. A novel procedure for generating solar irradiance TSYs

    Science.gov (United States)

    Fanego, Vicente Lara; Rubio, Jesús Pulgar; Peruchena, Carlos M. Fernández; Romeo, Martín Gastón; Tejera, Sara Moreno; Santigosa, Lourdes Ramírez; Balderrama, Rita X. Valenzuela; Tirado, Luis F. Zarzalejo; Pantaleón, Diego Bermejo; Pérez, Manuel Silva; Contreras, Manuel Pavón; García, Ana Bernardos; Anarte, Sergio Macías

    2017-06-01

    Typical Solar Years (TSYs) are key parameters for the solar energy industry. In particular, TSYs are mainly used for the design and bankability analysis of solar projects. In essence, a TSY intends to describe the expected long-term behavior of the solar resource (direct and/or global irradiance) into a condensed period of one year at the specific location of interest. A TSY differs from a conventional Typical Meteorological Year (TMY) by its absence of meteorological variables other than solar radiation. Concerning the probability of exceedance (Pe) needed for bankability, various scenarios are commonly used, with Pe90, Pe95 or even Pe99 being most usually required as unfavorable scenarios, along with the most widely used median scenario (Pe50). There is no consensus in the scientific community regarding the methodology for generating TSYs for any Pe scenario. Furthermore, the application of two different construction methods to the same original dataset could produce differing TSYs. Within this framework, a group of experts has been established by the Spanish Association for Standardization and Certification (AENOR) in order to propose a method that can be standardized. The method developed by this working group, referred to as the EVA method, is presented in this contribution. Its evaluation shows that it provides reasonable results for the two main irradiance components (direct and global), with low errors in the annual estimations for any given Pe. The EVA method also preserves the long-term statistics when the computed TSYs for a specific Pe are expanded from the monthly basis used in the generation of the TSY to higher time resolutions, such as 1 hour, which are necessary for the precise energy simulation of solar systems.

  4. Status of PILAC: A pion linac facility for 1-GeV pion physics at LAMPF

    International Nuclear Information System (INIS)

    Thiessen, H.A.

    1990-01-01

    A Pion Linac (PILAC) is being designed for LAMPF. Together with its high resolution beam line and spectrometer, the system is optimized to provide 10 9 pions per second on target and 200-keV resolution for the (π + ,K + ) reaction at 920, MeV. There will also be an achromatic beam line capable of utilizing the maximum energy available, thus opening up the possibility of a broad experimental program as is being discussed at this workshop. 12 figs

  5. Various models for pion probability distributions from heavy-ion collisions

    International Nuclear Information System (INIS)

    Mekjian, A.Z.; Mekjian, A.Z.; Schlei, B.R.; Strottman, D.; Schlei, B.R.

    1998-01-01

    Various models for pion multiplicity distributions produced in relativistic heavy ion collisions are discussed. The models include a relativistic hydrodynamic model, a thermodynamic description, an emitting source pion laser model, and a description which generates a negative binomial description. The approach developed can be used to discuss other cases which will be mentioned. The pion probability distributions for these various cases are compared. Comparison of the pion laser model and Bose-Einstein condensation in a laser trap and with the thermal model are made. The thermal model and hydrodynamic model are also used to illustrate why the number of pions never diverges and why the Bose-Einstein correction effects are relatively small. The pion emission strength η of a Poisson emitter and a critical density η c are connected in a thermal model by η/n c =e -m/T <1, and this fact reduces any Bose-Einstein correction effects in the number and number fluctuation of pions. Fluctuations can be much larger than Poisson in the pion laser model and for a negative binomial description. The clan representation of the negative binomial distribution due to Van Hove and Giovannini is discussed using the present description. Applications to CERN/NA44 and CERN/NA49 data are discussed in terms of the relativistic hydrodynamic model. copyright 1998 The American Physical Society

  6. A chiral model for excited pions

    International Nuclear Information System (INIS)

    Volkov, M.K.; Weiss, C.

    1996-01-01

    We study radially excited mesons (π', σ') in a simple extension of the Nambu-Jona-Lasinio model with a polynomial meson-quark form factor. The form factor is introduced so that the usual form of the NJL gap equation remains unchanged. We derive the effective Lagrangian for π- and π'-mesons which describes the decoupling of the Goldstone pion in the chiral limit in agreement with current algebra. For π' masses in the range of 750 MeV and 1300 MeV f π' /f π is found to be of an order of one per cent. 12 refs

  7. Evidence for pion absorption on four nucleons

    International Nuclear Information System (INIS)

    Rzehorz, B.; Backenstoss, G.; Dzemidzic, M.; Zagreb Univ.; Furic, M.; Zagreb Univ.; Hoffart, A.; Petkovic, T.; Zagreb Univ.; Ullrich, H.; Weyer, H.J.; Weiser, D.; Wildi, M.

    1996-01-01

    Experimental spectra from the coincident detection of three nucleons after the pion absorption in 4 He are displayed. The presence of a mechanism with four nucleons participating in the absorption process is made obvious. The total cross-sections for this absorption mode are: σ 4NA abs =(1.0±0.2)mb at T π =120 MeV and σ 4NA abs =(2.18± 0.65) mb at T π =210 MeV. (orig.)

  8. Nanoporous Membrane for Medical Grade Water Generation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — For NASA exploration missions to the Moon and Mars, medical grade water generation is a necessity. Adsorption filter technology has shown some promise, but requires...

  9. The pion mass: Looking for its origins

    International Nuclear Information System (INIS)

    Peccei, R.D.

    1985-10-01

    After explaining why pions are special excitations in QCD, I discuss how the pion mass reflects directly the dynamical scale of the strong interactions (Λsub(QCD)) and the scale of breaking of the weak interactions (Λsub(F)). To actually calculate the pion mass, however, requires understanding the origin of the quark masses and so I compare and contrast approaches to this latter problem, based on composite models and on superstrings. (orig.)

  10. [Differences between generations: relevant for medical education in the Netherlands].

    Science.gov (United States)

    Busari, Jamiu O; Scheele, Fedde

    2015-01-01

    Provision of care is increasingly being tailored to patients' wishes, which means that insight into the ideas, norms and values of the care-consumer are required. This approach is also beginning to filter through into medical education. We can differentiate generations on the basis of shared opinions, because groups with shared experiences usually share the same values. This is a useful line of approach if we wish to serve different generations of consumers better. At the moment there are four different generations influencing the setup and division of the healthcare services and relevant to medical education in the coming decades. Future education methods will have to be in line with the wishes of the generation from which new doctors come. In order to achieve better care for patients it is important to give 'thinking in generations' more attention in medical education.

  11. Pions scatter by nuclei

    International Nuclear Information System (INIS)

    Huefner, J.

    1975-01-01

    Are pions a good tool to study nuclei. If the emphasis of this question rests on ''tool'', the answer must be ''not yet.'' The reason: one does not even understand how a pion interacts with a nucleus. This is part of the many-body problem for strongly interacting particles and its study is a basic problem in physics. One must investigate questions like: Can one understand pion-nucleus interactions from pion-nucleon physics. How does a Δ-resonance look in nuclei. Once one has solved those basic problems, there will be spinoffs in medical, technical and nuclear areas. Then pions can be used as a tool to study nuclear properties

  12. Invariant potential for elastic pion--nucleus scattering

    International Nuclear Information System (INIS)

    Cammarata, J.B.; Banerjee, M.K.

    1976-01-01

    From the Wick-Dyson expansion of the exact propagator of a pion in the presence of a nucleus, an invariant potential for crossing symmetric elastic pion-nucleus scattering is obtained in terms of a series of pion-nucleon diagrams. The Chew-Low theory is used to develop a model in which the most important class of diagrams is effectively summed. Included in this model is the exclusion principle restriction on the pion-bound nucleon interaction, the effects of the binding of nucleons, a kinematic transformation of energy from the lab to the πN center of mass frame, and the Fermi motion and recoil of the target nucleons. From a numerical study of the effects of these processes on the π- 12 C total cross section, the relative importance of each is determined. Other processes contributing to the elastic scattering of pions not included in the present model are also discussed

  13. Sterilization validation for medical compresses at IRASM multipurpose irradiation facility

    International Nuclear Information System (INIS)

    Alexandru, Mioara; Ene, Mihaela

    2007-01-01

    In Romania, IRASM Radiation Processing Center is the unique supplier of radiation sterilization services-industrial scale (ISO 9001:2000 and ISO 13485:2003 certified). Its Laboratory of Microbiological Testing is the sole third party competent laboratory (GLPractice License, ISO 17025 certification in progress) for pharmaceutics and medical devices as well. We here refer to medical compresses as a distinct category of sterile products, made from different kind of hydrophilic materials (cotton, non-woven, polyurethane foam) with or without an impregnated ointment base (paraffin, plant extracts). These products are included in the class of medical devices, but for the sterilization validation, from microbiological point of view, there are important differences in testing method compared to the common medical devices (syringes, catheters, etc). In this paper, we present some results and practical solutions chosen to perform a sterilization validation, compliant with ISO 11137: 2006

  14. Joint resummation for pion wave function and pion transition form factor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hsiang-nan [Institute of Physics, Academia Sinica,Academia Rd., Taipei, Taiwan 115 (China); Department of Physics, National Cheng-Kung University,University Rd., Tainan, Taiwan 701 (China); Department of Physics, National Tsing-Hua University,Kuang-Fu Rd., Hsinchu, Taiwan 300 (China); Shen, Yue-Long [College of Information Science and Engineering, Ocean University of China,Songling Rd, Qingdao, Shandong 266100 (China); Wang, Yu-Ming [Institut für Theoretische Teilchenphysik und Kosmologie RWTH Aachen,Physikzentrum Otto-Blumenthal-Straße, D-52056 Aachen (Germany); Physik Department T31, Technische Universität München,James-Franck-Straße, D-85748 Garching (Germany)

    2014-01-03

    We construct an evolution equation for the pion wave function in the k{sub T} factorization formalism, whose solution sums the mixed logarithm ln xln k{sub T} to all orders, with x (k{sub T}) being a parton momentum fraction (transverse momentum). This joint resummation induces strong suppression of the pion wave function in the small x and large b regions, b being the impact parameter conjugate to k{sub T}, and improves the applicability of perturbative QCD to hard exclusive processes. The above effect is similar to those from the conventional threshold resummation for the double logarithm ln{sup 2} x and the conventional k{sub T} resummation for ln{sup 2} k{sub T}. Combining the evolution equation for the hard kernel, we are able to organize all large logarithms in the γ{sup ∗}π{sup 0}→γ scattering, and to establish a scheme-independent k{sub T} factorization formula. It will be shown that the significance of next-to-leading-order contributions and saturation behaviors of this process at high energy differ from those under the conventional resummations. It implies that QCD logarithmic corrections to a process must be handled appropriately, before its data are used to extract a hadron wave function. Our predictions for the involved pion transition form factor, derived under the joint resummation and the input of a non-asymptotic pion wave function with the second Gegenbauer moment a{sub 2}=0.05, match reasonably well the CLEO, BaBar, and Belle data.

  15. Toy model for pion production in nucleon-nucleon collisions

    International Nuclear Information System (INIS)

    Hanhart, C.; Miller, G. A.; Myhrer, F.; Sato, T.; Kolck, U. van

    2001-01-01

    We develop a toy model for pion production in nucleon-nucleon collisions that reproduces some of the features of the chiral Lagrangian calculations. We calculate the production amplitude and examine some common approximations

  16. The possibility for a pion polarizability measurement at COMPASS

    CERN Document Server

    Guskov, A

    2010-01-01

    The pion electromagnetic structure can be probed in $\\pi^{−}+(A,Z)\\rightarrow\\pi^{-}+(A,Z) + \\gamma$ Compton scattering in inverse kinematics (Primakoff reaction) and described by the electric $(\\alpha_{\\pi})$ and the magnetic $(\\beta_{\\pi})$ polarizabilities that depend on the rigidity of pion’s internal structure as a composite particle. Values for pion polarizabilities can be extracted from the comparison of the differential cross section for scattering of point-like pions with the measured cross section. The opportunity to measure pion polarizability via the Primakoff reaction at the COMPASS experiment was studied with a $\\pi^{−}$ beam of 190 GeV. The obtained results are used for preparation of the new measurement.

  17. A Compact Medical Oxygen Generator for Spacecraft, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An on-board oxygen concentrator is required during long duration manned space missions to supply medical oxygen. Commercial medical oxygen generators are pressure...

  18. Pion radiation for high grade astrocytoma: results of a randomized study

    International Nuclear Information System (INIS)

    Pickles, Tom; Goodman, George B.; Rheaume, Dorianne E.; Duncan, Graeme G.; Fryer, Chris J.; Bhimji, Shamim; Ludgate, Charles; Syndikus, Isabel; Graham, Peter; Dimitrov, Mario; Bowen, Julie

    1997-01-01

    Purpose: This study attempted to compare within a randomized study the outcome of pion radiation therapy vs. conventional photon irradiation for the treatment of high-grade astrocytomas. Methods and Materials: Eighty-four patients were randomized to pion therapy (33-34.5 Gyπ), or conventional photon irradiation (60 Gy). Entry criteria included astrocytoma (modified Kernohan high Grade 3 or Grade 4), age 18-70, Karnofsky performance status (KPS) ≥50, ability to start irradiation within 30 days of surgery, unifocal tumor, and treatment volume < 850 cc. The high-dose volume in both arms was computed tomography enhancement plus a 2-cm margin. The study was designed with the power to detect a twofold difference between arms. Results: Eighty-one eligible patients were equally balanced for all known prognostic variables. Pion patients started radiation 7 days earlier on average than photon patients, but other treatment-related variables did not differ. There were no significant differences for either early or late radiation toxicity between treatment arms. Actuarial survival analysis shows no differences in terms of time to local recurrence or overall survival where median survival was 10 months in both arms (p = 0.22). The physician-assessed KPS and patient-assessed quality of life (QOL) measurements were generally maintained within 10 percentage points until shortly before tumor recurrence. There was no apparent difference in the serial KPS or QOL scores between treatment arms. Conclusion: In contrast to high linear energy transfer (LET) therapy for central nervous system tumors, such as neutron or neon therapy, the safety of pion therapy, which is of intermediate LET, has been reaffirmed. However, this study has demonstrated no therapeutic gain for pion therapy of glioblastoma

  19. Medical irradiation in 10 episodes

    International Nuclear Information System (INIS)

    Cordoliani, Y.S.; Kalifa, G.; Lefaure, Ch.; Lochard, J.

    2000-01-01

    Illustrated by strip cartoons, this publication recalls the historical development in the field of X rays and their medical use, explains the risks associated with the use of radioactive rays and therefore that a the use of a radiography is not always required. It indicates and comments the share of medical irradiation in the whole radioactive exposure, and the adopted precaution principle. It outlines that risks are more important for embryos, foetuses, babies and young children, outlines the best practices in the field of radiography. It presents the various radionuclides present in the human body and their medical use or application, evokes other available techniques used to view inside the body (echography, magnetic resonance imaging), the use of radiological technical for medical purposes on healthy people and as curative means. The progress associated with the introduction of digital processing is evoked

  20. Comparative studies on the effect of negative pions, 60Co gamma irradiation and hyperthermia on an in vitro 'tumour model'

    International Nuclear Information System (INIS)

    Luecke-Huhle, C.; Dertinger, H.; Schlag, H.; Weibezahn, K.F.

    1977-01-01

    Multicellular spheriods of Chinese hamster cells (V79) are much more resistant than monolayer cultures of the same cell line; this is observed after 60 Co γ-irradiation, after hyperthermic treatment, after combined treatment of heat with 60 Co γ-radiation and after exposure to negative pi-mesons. Intercellular communication within the three-dimensional cell clones seems to be responsible for an enhanced repair capacity for sub-lethal as well as for potentially lethal damage. While the response of spheroid cells to 60 Co γ-irradiation is almost independent of the state of growth, there is a clear difference in survival whether exponentially growing outer cells or inner plateau phase cells are exposed to heat: moderate heat treatment (4h at 42 0 C) leads to a greater killing efficiency of exponentially growing cells while the inner non-cycling cells exhibit a recruitment of resting cells into the proliferative compartment as demonstrated by means of flow-microfluorometry. Hyperthermia in combination with 60 Co γ-irradiation was shown to eliminate hypoxic cells and to yield a thermal enhancement ratio comparable to the RBE value obtained after pion irradiation at maximum LET. (author)

  1. MCM generator: a Java-based tool for generating medical metadata.

    Science.gov (United States)

    Munoz, F; Hersh, W

    1998-01-01

    In a previous paper we introduced the need to implement a mechanism to facilitate the discovery of relevant Web medical documents. We maintained that the use of META tags, specifically ones that define the medical subject and resource type of a document, help towards this goal. We have now developed a tool to facilitate the generation of these tags for the authors of medical documents. Written entirely in Java, this tool makes use of the SAPHIRE server, and helps the author identify the Medical Subject Heading terms that most appropriately describe the subject of the document. Furthermore, it allows the author to generate metadata tags for the 15 elements that the Dublin Core considers as core elements in the description of a document. This paper describes the use of this tool in the cataloguing of Web and non-Web medical documents, such as images, movie, and sound files.

  2. Study of energetic hydrogen isotopes emitted at photoemulsion nuclei disintegration under 60 GeV pion irradiation

    International Nuclear Information System (INIS)

    Borisenko, A.I.; Kazanskaya, A.P.; Lazareva, T.P.; Morozova, P.V.; Takibaev, Zh.S.

    1979-01-01

    Experimental data on emission of protons deuterons and tritons with the kinetic energy exceeding 25 MeV/nucleon at disintegration of photoemulsion nuclei under 60 GeV pion irradiation are presented. A stack of BR-2 type nuclear photoemulsions was exposed in the π - -beam of the Serpukhov accelerator. The technique of particle identification is discussed. Data on the cross sections, angular and momentum distributions of the protons, deuterons and tritons as well as the probability of their production as a function of the number of emitted particles in a star are presented. No substantial differences in the energy spectra and angular distributions of the protons, deuterons and tritons have been observed. It has been established from the analysis of the data that to interprete the mechanism of the deuteron production the Butler-Pearson model can be applied, but the data on triton production mechanism obtained only at 60 GeV are insufficient for definite conclusions

  3. The quasi deuteron model for low energy pion absorption

    International Nuclear Information System (INIS)

    Gouweloos, M.

    1986-01-01

    In this thesis pion absorption in complex nuclei is studied in the quasi-deuteron model in which the pion is absorbed on a nucleon pair in the nucleus. The mechanism is studied in the low-energy domain since then the in-medium (pi→NN) operator turns out to be of simple character. In Ch. 2 and 3 this operator is constructed and analytical expressions are derived for (pi,NN) distributions in a plane wave impulse approximation for nuclei. The results turn out to be very useful for developing insight in the possibilities inherent in the QDM and the interpretation of the results in later chapters. Ch. 4 to 6 are devoted to the more realistic distorted wave calculations. In Ch. 4 the formal framework is presented and the calculational details are discussed. Ch.5 and 6 contain the comparison to stopped pion and in-flight data respectively. In Ch. 7 the main results are summarized. (Auth.)

  4. The CHAOS spectrometer for pion physics at TRIUMF

    International Nuclear Information System (INIS)

    Smith, G.R.; Amaudruz, P.A.; Brack, J.T.

    1994-12-01

    The Canadian high acceptance orbit spectrometer (CHAOS) is a unique magnetic spectrometer system recently commissioned for studies of pion induced reactions at TRIUMF. It is based on a cylindrical dipole magnet producing vertical magnetic fields up to 1.6 T. The scattering target is located in the center of the magnet. Charged particle tracks produced by pion interactions there are identified using four concentric cylindrical wire chambers surrounding the target. Particle identification and track multiplicity are determined by cylindrical layers of scintillation counters and lead glass Cerenkov counters, which also provide a first level trigger. A sophisticated second level trigger system permits pion fluxes in excess of 5 MHz to be employed. The detector subtends 360 o in the horizontal plane, and ±7 o out of this plane for a solid angle coverage approximately 10% of 4π sr. The momentum resolution delivered by the detector system is 1% (σ). (author). 16 refs., 12 figs

  5. Cancer following medical irradiation

    International Nuclear Information System (INIS)

    Boice, J.D.

    1981-01-01

    Several generalizations about radiation carcinogenesis can be made: (1) a single exposure is sufficient to elevate cancer incidence many years later; (2) radiation-induced cancer cannot be distinguished from naturally occurring cancer, i.e., there is no unique radiogenic cancer; (3) all cancers appear to be increased after irradiation with the exception of chronic lymphocytic leukemia, and possibly Hodgkin's disease, cervical cancer, and a few others; (4) the breast, thyroid, and bone marrow appear especially radiosensitive; (5) leukemia is the most prominent radiogenic tumor and shows a wave-like pattern of excess incidence over time, and the excess begins within two to four years, peaks about six to eight years, and decreases to normal levels about 25 years later; (6) solid tumors have a minimum latent period of about ten years, and for several cancers, the temporal pattern of incidence appears to follow the natural incidence, i.e., the cancers do not occur before the ages normally associated with increased incidence, implying that age-dependent factors influence the expression of disease; (7) age at exposure is perhaps the most important host factor influencing subsequent cancer risk; (8) the percentage increase in cancer incidence per rad is not the same for all cancers, i.e., some cancers of high natural incidence, e.g., colon, have low relative risks and some cancers of low natural incidence, e.g., thyroid, have high relative risks; (9) dose-effect curves are often linear, but curvilinearity is also observed and is possibly associated with the need for two ionizing events for transformation to occur at low doses, the influence of cell sterilization at moderate doses, the likelihood of wasted dose at high doses, and/or the influence of factors that effect the expression of disease

  6. Low-energy photo- and electroproduction for physical pions

    International Nuclear Information System (INIS)

    MacMullen, J.T.

    1979-02-01

    The background resonance Δ(1230), Nsup(*)(1520), Nsup(*)(1470) and Nsup(*)(1535)pion and axial-vector amplitudes are first calculated in the soft pion and on-shell configuration, respectively. Then a comparison is made with the usual soft pion theorems and on-shell low-energy expansions of current algebra as worked out in the previous paper. The agreement is good and we also deduce a nucleon dipole form factor axial-vector mass of msub(A)approximately equal to 1,23 GeV. Finally an approximate value for the non-strange current quark mass of m equal to 0,64 +- 1,11μ is extracted from the data

  7. Experimental studies of free defect generation during irradiation: Implications for reactor environments

    International Nuclear Information System (INIS)

    Rehn, L.E.; Birtcher, R.C.

    1993-01-01

    Over the past several years, systematic experiments have revealed that irradiations which generate energetically dense cascades are much less effective than light-ion, MeV electron, or thermal neutron irradiations at producing freely-migrating defects. In this paper, the systematic results on freely-migrating defect production from ion irradiation studies are briefly summarized. Difficulties with applying a simple extrapolation of the ion-irradiation results to neutron environments are discussed. This discussion, coupled with our existing knowledge of neutron-induced property changes, indicates that Compton scattering, and the (n,γ), (n,He) and (n,p) nuclear reactions, are considerably more important for producing freely-migrating defects than was previously realized

  8. Critique of a pion exchange model for interquark forces

    International Nuclear Information System (INIS)

    Isgur, Nathan

    2000-01-01

    I describe four serious defects of a widely discussed pion exchange model for interquark forces: it does not solve the ''spin-orbit problem'' as advertised, it fails to describe the internal structure of baryon resonances, it leads to disastrous conclusions when extended to mesons, and it is not reasonably connected to the physics of heavy-light systems. While extensions of the original pion exchange model may be able to correct these defects, this catalogue of criticisms defines some of the most formidable problems such elaborations must address. (c) 2000 The American Physical Society

  9. Evidence for delta-hole components from pion reactions

    International Nuclear Information System (INIS)

    Morris, C.L.

    1982-01-01

    Some anomalies observed in pion-induced reactions have been qualitatively explained with a model which includes Δ 3 3 admixtures in low lying nuclear states. Semi-quantitative analysis of these effects indicates the amplitudes for the Δ 3 3 admixtures necessary to explain these effects are on the order of a few percent. Although a more rigorous theoretical treatment of this problem is necessary, it appears that pion-induced reactions may provide a tool with which the spectroscopy of these Δ 3 3 -admixtures can be studied

  10. Device for the generation of homogeneous dose distributions in irradiated materials

    International Nuclear Information System (INIS)

    Leonhardt, J.; Schulze, H.; Boes, J.; Decker, U.; Schmidt, J.

    1985-01-01

    The invention has been directed at a device for the generation of homogeneous dose distributions in materials irradiated by charged particles. This device can be applied to the initiation of radiation-chemical reactions in solids, of cross-linking and vulcanizing reactors, of crystal defect annealings, etc. A movable absorber (e.g. a wedge or a solid of revolution) which periodically changes the energy of particles striking the specimen has been installed in the beam hole of the beam generating system

  11. Damage functions generation for polyatomic materials irradiated in test reactors

    International Nuclear Information System (INIS)

    Alberman, A.; Lesueur, D.

    1987-06-01

    Neutron exposure parameters in polyatomic materials is of great importance for fusion technology programs. The COMPOSI code computes the number of displaced atoms of sub-lattice ''j'' induced by one atom of sub-lattice ''i'' either by direct collision or through intermediate knocked atom. The code uses Lindhard equations; it is solved by iterative process. The atomic displacements cross-sections, as a function of neutron energy are derived by folding previous results with ''i'' type PKA. Moreover the COMPOSI code may include recoils from charged particles e.g.: Alpha + Triton from Li 6 capture in Li Al 0 2 . These responses in various spectra are discussed [fr

  12. Safety assessment for the 24 CANFLEX-NU bundle demonstration irradiation at Wolsong-1 generation

    Energy Technology Data Exchange (ETDEWEB)

    Suk, Ho Chun; Cho, M. S.; Jun, J. S. and others

    2001-06-01

    This document is a report on the safety assessment for the 24 CANFLEX-NU(CANDU Flexible fuelling - Natural Uranium) fuel bundle demonstration irradiation at Wolsong-1 Generating Station. The CANFLEX fuel bundle as a CANDU advanced fuel has been jointly developed by KAERI/AECL. This document describes the rationale for the demonstration irradiation and comments on the Korean government licensing issues such as the status of the CANFLEX fuel irradiations at NRU research reactor in AECL, status and plan of the CANFLEX fuel irradiations at a CANDU-6 power reactor, status of the water CHF(Critical Heat Flux) test at Stern Laboratories and the CHF correlation. This documents presents an assessment the consequences of postulated accidents with all safety system available during demonstration irradiation of 24 CANFLEX-NU fuel bundles at Wolsong-1 Generating Station. The assessment is made by two kinds of approaches. One approach is based on the document of the safety assessment for the 24 CANFLEX-NU fuel bundle demonstration irradiation at Point Lepreau Generating Station. The other approach is taken from the safety analyses using the analysis methods and assumptions used in the final safety reports on the 600 MWe CANDU-PHWR Wolsung-2, 3, and 4 Nuclear Power Plants for the Korea Electric Power Cooperation. The analyses are not comprehensive reviews of the postulated accidents, but examination of the expected difference in accident consequences because of the presence of 24 CANFLEX fuel bundles in two channels. The approach is to compare the difference to the safety margin for 37-element bundle cases.

  13. Zero-degree injection line for PILAC, the proposed Los Alamos Pion Linac

    International Nuclear Information System (INIS)

    Blind, B.

    1991-01-01

    In this paper, an optimized injection line for PILAC, the proposed Los Alamos Pion Linac, is presented. With the other optimized components (pion source, accelerator, and high-resolution beamline and spectrometer), the system is capable of delivering 10 9 920-MeV pions per second to the target. 3 refs., 2 figs

  14. Critique of a pion exchange model for interquark forces

    International Nuclear Information System (INIS)

    Isgur, N.

    1999-01-01

    The author describes four serious defects of a widely discuss pion exchange model for interquark forces: it doesn't solve the ''spin-orbit problem'' as advertised, it fails to describe the internal structure of baryon resonances, it leads to disastrous conclusions when extended to mesons, and it is not reasonably connected to the physics of heavy-light systems

  15. Total cross sections for pion charge exchange on the proton

    International Nuclear Information System (INIS)

    Breitschopf, J.

    2006-01-01

    This work describes the measurement of total SCX cross sections employing a new 4π scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4π detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH 2 target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole Δ-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4±1.5)%. The exact value depends on the SCX literature data included and on the parameters of the Δ 0 Breit-Wigner resonance describing the p 33 -waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin symmetry breaking. Interestingly

  16. Total cross sections for pion charge exchange on the proton

    Energy Technology Data Exchange (ETDEWEB)

    Breitschopf, J.

    2006-04-28

    This work describes the measurement of total SCX cross sections employing a new 4{pi} scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4{pi} detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH{sub 2} target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole {delta}-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4{+-}1.5)%. The exact value depends on the SCX literature data included and on the parameters of the {delta}{sup 0} Breit-Wigner resonance describing the p{sub 33}-waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin

  17. A new Monte Carlo program for calculations of dose distributions within tissue equivalent phantoms irradiated from π--meson beams

    International Nuclear Information System (INIS)

    Przybilla, G.

    1980-11-01

    The present paper reports on the structure and first results from a new Monte Carlo programme for calculations of energy distributions within tissue equivalent phantoms irradiated from π - -beams. Each pion or generated secondary particle is transported until to the complete loss of its kinetic energy taking into account pion processes like multiple Coulomb scattering, pion reactions in flight and absorption of stopped pions. The code uses mainly data from experiments, and physical models have been added only in cases of lacking data. Depth dose curves for a pensil beam of 170 MeV/c within a water phantom are discussed as a function of various parameters. Isodose contours are plotted resulting from a convolution of an extended beam profile and the dose distribution of a pencil beams. (orig.) [de

  18. PIPIT: a momentum space optical potential code for pions

    Energy Technology Data Exchange (ETDEWEB)

    Eisenstein, R A [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics; Tabakin, F [Pittsburgh Univ., Pa. (USA). Dept. of Physics

    1976-11-01

    Angular distributions for the elastic scattering of pions are generated by summing a partial wave series. The elastic T-matrix elements for each partial wave are obtained by solving a relativistic Lippmann-Schwinger equation in momentum space using a matrix inversion technique. Basically the Coulomb interaction is included exactly using the method of Vincent and Phatak. The ..pi..N amplitude is obtained from phase shift information on-shell and incorporates a separable off-shell form factor to ensure a physically reasonable off-shell extrapolation. The ..pi..N interaction is of finite range and a kinematic transformation procedure is used to express the ..pi..N amplitude in the ..pi.. nucleus frame. A maximum of 30 partial waves can be used in the present version of the program to calculate the cross section. The Lippmann-Schwinger equation is presently solved for each partial wave by inverting a 34x34 supermatrix. At very high energies, larger dimensions may be required. The present version of the code uses a separable non-local ..pi..N potential of finite range; other types of non-localities, or non-separable potentials, may be of physical interest.

  19. Analyses of multi-pion Hanbury Brown–Twiss correlations for the pion-emitting sources with Bose–Einstein condensation

    Science.gov (United States)

    Bary, Ghulam; Ru, Peng; Zhang, Wei-Ning

    2018-06-01

    We calculate the three- and four-particle correlations of identical pions in an evolving pion gas (EPG) model with Bose–Einstein condensation. The multi-pion correlation functions in the EPG model are analyzed in different momentum intervals and compared with the experimental data for Pb–Pb collisions at \\sqrt{{s}{NN}}=2.76 {TeV}. It is found that the multi-pion correlation functions and cumulant correlation functions are sensitive to the condensation fraction of the EPG sources in the low average transverse-momentum intervals of the three and four pions. The model results of the multi-pion correlations are consistent with the experimental data in a considerable degree, which gives a source condensation fraction between 16% and 47%.

  20. Radiobiological work using a negative pion beam at the Rutherford Laboratory 1971-76

    International Nuclear Information System (INIS)

    Ellis, R.E.; Lindop, P.J.; Coggle, J.E.; Fraser, G.

    1976-08-01

    The subject is discussed in two sections: physics experiments (including, inter alia, dose measurement, LET distribution, radiation products of spallation); radiobiological studies (including separate reports as follows: review of experimental programme; some in vivo effects of negative pions in mice; survival and recovery of Hela cells in vitro; negative pion dose-response curves for frozen Hela cells; response of vicia faba to irradiation with negative pions; pion experiments with chromosome aberrations). (U.K.)

  1. A model for pion-pion scattering in large-N QCD

    Energy Technology Data Exchange (ETDEWEB)

    Veneziano, G. [Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); Collège de France,11 place M. Berthelot, 75005 Paris (France); Yankielowicz, S. [Raymond and Beverly Sackler School of Physics Tel-Aviv University,Ramat-Aviv 69978 (Israel); Onofri, E. [I.N.F.N., Gruppo Collegato di Parma, c/o Department of Mathematical,Physical and Computer Sciences, Università di Parma,Parco Area delle Scienze 7/a, Parma, 43124 (Italy)

    2017-04-26

    Following up on recent work by Caron-Huot et al. we consider a generalization of the old Lovelace-Shapiro model as a toy model for ππ scattering satisfying (most of) the properties expected to hold in (’t Hooft’s) large-N limit of massless QCD. In particular, the model has asymptotically linear and parallel Regge trajectories at positive t, a positive leading Regge intercept α{sub 0}<1, and an effective bending of the trajectories in the negative-t region producing a fixed branch point at J=0 for tfor all values of s and J) imposes strong constraints on the allowed region in the α{sub 0}-β-γ parameter space, which nicely includes a physically interesting region around α{sub 0}=0.5, β=2 and γ=3. The full consistency of the model would require an extension to multi-pion processes, a program we do not undertake in this paper.

  2. Generation of daily global solar irradiation with support vector machines for regression

    International Nuclear Information System (INIS)

    Antonanzas-Torres, F.; Urraca, R.; Antonanzas, J.; Fernandez-Ceniceros, J.; Martinez-de-Pison, F.J.

    2015-01-01

    Highlights: • New methodology for estimation of daily solar irradiation with SVR. • Automatic procedure for training models and selecting meteorological features. • This methodology outperforms other well-known parametric and numeric techniques. - Abstract: Solar global irradiation is barely recorded in isolated rural areas around the world. Traditionally, solar resource estimation has been performed using parametric-empirical models based on the relationship of solar irradiation with other atmospheric and commonly measured variables, such as temperatures, rainfall, and sunshine duration, achieving a relatively high level of certainty. Considerable improvement in soft-computing techniques, which have been applied extensively in many research fields, has lead to improvements in solar global irradiation modeling, although most of these techniques lack spatial generalization. This new methodology proposes support vector machines for regression with optimized variable selection via genetic algorithms to generate non-locally dependent and accurate models. A case of study in Spain has demonstrated the value of this methodology. It achieved a striking reduction in the mean absolute error (MAE) – 41.4% and 19.9% – as compared to classic parametric models; Bristow & Campbell and Antonanzas-Torres et al., respectively

  3. QCD constraints for the electromagnetic form factor of the pion

    International Nuclear Information System (INIS)

    Machet, B.

    1980-07-01

    Using the modulus representation, we derive constraints for the behaviour of the electromagnetic form factor of the pion in the time like region [1 GeV 2 , + infinity[, from information given by perturbative QCD in the space like region [-μ 2 , - infinity[. A phenomenological μ dependent upper bound for the exponent of the first non leading logarithmic correction is deduced. Restrictions and problems of the method are discussed

  4. Code of practice for the design and safe operation of non-medical irradiation facilities (1988)

    International Nuclear Information System (INIS)

    1988-01-01

    This Code establishes requirements for the design and operation of irradiation facilities which use X-rays, electrons or gamma radiation for non-medical purposes such as the sterilisation of therapeutic goods. These requirements aim to ensure that exposure of workers and members of the public to ionizing and non-ionizing radiation as well as to noxious gases and radioactive contamination of the environment and facilities are controlled through the design of engineering safety features, approved administrative controls and appropriate radiation monitoring [fr

  5. Internal stress distribution for generating closure domains in laser-irradiated Fe–3%Si(110) steels

    International Nuclear Information System (INIS)

    Iwata, Keiji; Imafuku, Muneyuki; Orihara, Hideto; Sakai, Yusuke; Ohya, Shin-Ichi; Suzuki, Tamaki; Shobu, Takahisa; Akita, Koichi; Ishiyama, Kazushi

    2015-01-01

    Internal stress distribution for generating closure domains occurring in laser-irradiated Fe–3%Si(110) steels was investigated using high-energy X-ray analysis and domain theory based on the variational principle. The measured triaxial stresses inside the specimen were compressive and the stress in the rolling direction became more dominant than stresses in the other directions. The calculations based on the variational principle of magnetic energy for closure domains showed that the measured triaxial stresses made the closure domains more stable than the basic domain without closure domains. The experimental and calculation results reveal that the laser-introduced internal stresses result in the occurrence of the closure domains

  6. Collins fragmentation function for pions and kaons in a spectator model

    Energy Technology Data Exchange (ETDEWEB)

    Bacchetta, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gamberg, L.P. [Penn State Univ., Berks, PA (United States). Dept. of Physics; Goldstein, G.R. [Tufts Univ., Medford, MA (United States). Dept. of Physics and Astronomy; Mukherjee, A. [Indian Institute of Technology Bombay, Mumbai (India). Physics Dept.

    2007-07-15

    We calculate the Collins fragmentation function in the framework of a spectator model with pseudoscalar pion-quark coupling and a Gaussian form factor at the vertex. We determine the model parameters by fitting the unpolarized fragmentation function for pions and kaons. We show that the Collins function for the pions in this model is in reasonable agreement with recent parametrizations obtained by fits of the available data. In addition, we compute for the first time the Collins function for the kaons. (orig.)

  7. Estimation of risks from medical irradiation

    International Nuclear Information System (INIS)

    Persson, B.R.R.

    1983-01-01

    This paper discuss various concepts of quantifying risks from medical irradiation. The expected individual risk from specific medical examination can be derived by estimation the dose-equivalent in different organs and tissues and apply the risk factors recommended for these tissues. A more practical way is to estimate or measure the energy imparted which has been found to correlate quite well with the total risk derived by summing up the risks for the involved tissues. The effective dose-equivalent concept can be used to derive the collective effective dose-equivalent in a population in order to compare the contribution from medical exposure with the contribution from other sources of irradiation in the society. In many countries it is thus shown that medical exposures gives the largest man-made contribution to the population dose

  8. Dosimetry of pion beams

    International Nuclear Information System (INIS)

    Dicello, J.F.

    1975-01-01

    Negative pion beams are probably the most esoteric and most complicated type of radiation which has been suggested for use in clinical radiotherapy. Because of the limited availability of pion beams in the past, even to nuclear physicists, there exist relatively fewer basic data for this modality. Pion dosimetry is discussed

  9. Solid-state pulse modulator using Marx generator for a medical linac electron-gun

    Science.gov (United States)

    Lim, Heuijin; Hyeok Jeong, Dong; Lee, Manwoo; Lee, Mujin; Yi, Jungyu; Yang, Kwangmo; Ro, Sung Chae

    2016-04-01

    A medical linac is used for the cancer treatment and consists of an accelerating column, waveguide components, a magnetron, an electron-gun, a pulse modulator, and an irradiation system. The pulse modulator based on hydrogen thyratron-switched pulse-forming network is commonly used in linac. As the improvement of the high power semiconductors in switching speed, voltage rating, and current rating, an insulated gate bipolar transistor has become the more popular device used for pulsed power systems. We propose a solid-state pulse modulator to generator high voltage by multi-stacked storage-switch stages based on the Marx generator. The advantage of our modulator comes from the use of two semiconductors to control charging and discharging of the storage capacitor at each stage and it allows to generate the pulse with various amplitudes, widths, and shapes. In addition, a gate driver for two semiconductors is designed to reduce the control channels and to protect the circuits. It is developed for providing the pulsed power to a medical linac electron-gun that requires 25 kV and 1 A as the first application. In order to improve the power efficiency and achieve the compactness modulator, a capacitor charging power supply, a Marx pulse generator, and an electron-gun heater isolated transformer are constructed and integrated. This technology is also being developed to extend the high power pulsed system with > 1 MW and also other applications such as a plasma immersed ion implantation and a micro pulse electrostatic precipitator which especially require variable pulse shape and high repetition rate > 1 kHz. The paper describes the design features and the construction of this solid-state pulse modulator. Also shown are the performance results into the linac electron-gun.

  10. Solid-state pulse modulator using Marx generator for a medical linac electron-gun

    International Nuclear Information System (INIS)

    Lim, Heuijin; Jeong, Dong Hyeok; Lee, Manwoo; Lee, Mujin; Yi, Jungyu; Yang, Kwangmo; Ro, Sung Chae

    2016-01-01

    A medical linac is used for the cancer treatment and consists of an accelerating column, waveguide components, a magnetron, an electron-gun, a pulse modulator, and an irradiation system. The pulse modulator based on hydrogen thyratron-switched pulse-forming network is commonly used in linac. As the improvement of the high power semiconductors in switching speed, voltage rating, and current rating, an insulated gate bipolar transistor has become the more popular device used for pulsed power systems. We propose a solid-state pulse modulator to generator high voltage by multi-stacked storage-switch stages based on the Marx generator. The advantage of our modulator comes from the use of two semiconductors to control charging and discharging of the storage capacitor at each stage and it allows to generate the pulse with various amplitudes, widths, and shapes. In addition, a gate driver for two semiconductors is designed to reduce the control channels and to protect the circuits. It is developed for providing the pulsed power to a medical linac electron-gun that requires 25 kV and 1 A as the first application. In order to improve the power efficiency and achieve the compactness modulator, a capacitor charging power supply, a Marx pulse generator, and an electron-gun heater isolated transformer are constructed and integrated. This technology is also being developed to extend the high power pulsed system with > 1 MW and also other applications such as a plasma immersed ion implantation and a micro pulse electrostatic precipitator which especially require variable pulse shape and high repetition rate > 1 kHz. The paper describes the design features and the construction of this solid-state pulse modulator. Also shown are the performance results into the linac electron-gun

  11. Signal generation in highly irradiated silicon microstrip detectors for the ATLAS experiment

    International Nuclear Information System (INIS)

    Ruggiero, Gennaro

    2003-01-01

    Silicon detectors are the most diffused tracking devices in High Energy Physics (HEP). The reason of such success can be found in the characteristics of the material together with the existing advanced technology for the fabrication of these devices. Nevertheless in many modem HEP experiments the observation of vary rare events require data taking at high luminosity with a consequent extremely intense hadron radiation field that damages the silicon and degrades the performance of these devices. In this thesis work a detailed study of the signal generation in microstrip detectors has been produced with a special care for the ATLAS semiconductor tracker geometry. This has required a development of an appropriate setup to perform measurements with Transient Current/ Charge Technique. This has allowed studying the evolution of the signal in several microstrips detector samples irradiated at fluences covering the range expected in the ATLAS Semiconductor Tracker. For a better understanding of these measurements a powerful software package that simulates the signal generation in these devices has been developed. Moreover in this thesis it has been also shown that the degradation due to radiation in silicon detectors can be strongly reduced if the data taking is done with detectors operated at 130 K. This makes low temperature operation that benefits of the recovery of the charge collection efficiency in highly irradiated silicon detectors (also known as Lazarus effect) an optimal option for future high luminosity experiments. (author)

  12. A methodology for the stochastic generation of hourly synthetic direct normal irradiation time series

    Science.gov (United States)

    Larrañeta, M.; Moreno-Tejera, S.; Lillo-Bravo, I.; Silva-Pérez, M. A.

    2018-02-01

    Many of the available solar radiation databases only provide global horizontal irradiance (GHI) while there is a growing need of extensive databases of direct normal radiation (DNI) mainly for the development of concentrated solar power and concentrated photovoltaic technologies. In the present work, we propose a methodology for the generation of synthetic DNI hourly data from the hourly average GHI values by dividing the irradiance into a deterministic and stochastic component intending to emulate the dynamics of the solar radiation. The deterministic component is modeled through a simple classical model. The stochastic component is fitted to measured data in order to maintain the consistency of the synthetic data with the state of the sky, generating statistically significant DNI data with a cumulative frequency distribution very similar to the measured data. The adaptation and application of the model to the location of Seville shows significant improvements in terms of frequency distribution over the classical models. The proposed methodology applied to other locations with different climatological characteristics better results than the classical models in terms of frequency distribution reaching a reduction of the 50% in the Finkelstein-Schafer (FS) and Kolmogorov-Smirnov test integral (KSI) statistics.

  13. Vacuum design for the disk-and-washer accelerator structure

    International Nuclear Information System (INIS)

    Ruhe, J.R.; Hansborough, L.D.

    1982-02-01

    The disk-and-washer (DAW) accelerator structure is being developed for several applications. Because of its complicated geometry and newness, vacuum calculations for the DAW accelerator structure are not yet formalized. The applicable vacuum equations for this structure are presented and correlations for it have been made with the vacuum data from the Clinton P. Anderson Meson Physics Facility side-coupled accelerator structure. A calculation is presented for the DAW structure proposed for the Pion Generator for Medical Irradiations (PIGMI) accelerator

  14. Multi-pion production

    International Nuclear Information System (INIS)

    Beavis, D.; Fung, S.Y.; Gorn, W.; Keane, D.; Liu, Y.M.; Poe, R.T.; VanDalen, G.; Vient, M.

    1984-01-01

    Preliminary analysis of pion production in 1.2 GeV/nucleon Kr-RbBr collisions is presented. The negative pion multiplicity is consistent with a convolution of Poisson distributions and a freeze-out density between 1/3 and 1/2 normal nuclear density is extracted. Global negative pion kinematic variables are used to search for possible structure in the multi-pion emission. No evidence for structured emission or conservation constraints is found. Pion interferometry analysis gives a source radius of 5.4 +- 1.2 Fermi and a freeze-out density of .3 +- .2 times normal nuclear density. 10 refs., 5 figs

  15. Feasibility studies on the potential of employing electron beam machine for non-medical products irradiation in Malaysia

    International Nuclear Information System (INIS)

    Siti Aiasah Hashim; Sarada Idris

    2012-01-01

    In Malaysia, two 10 MeV irradiators were installed by private companies as part of in-house manufacturing or as third party sterilization service provider. At the same time, the 3 MeV EPS 3000 machine at Nuclear Malaysia is providing irradiation services for various purposes and products. With the current increase in demand in automotive manufacturing for better quality harnesses and components, the irradiation service at Nuclear Malaysia had to provide extended time to cope with the requests. This paper looks at the potential of setting up a commercial irradiation facility to cater for non-medical products such as automotive wires and tubing, food, fruits, cosmetic and semiconductors. Intensive interviews with related industries were carried out throughout Malaysia to evaluate the potential of installing electron beam machine for commercial irradiation. The results show that a majority of non-medical industries are not aware of the irradiation service provided by Nuclear Malaysia, although many understand the need for it. A multipurpose irradiator is desired in order to optimize the usage since a single dedicated machine may be too costly to sustain. (author)

  16. Mechanisms for pion production in heavy ion collisions

    International Nuclear Information System (INIS)

    Pfeiffer, M.

    1991-01-01

    In the following contribution some aspects concerning pion production in heavy ion collisions will be discussed. After a general introduction the properties of pions and the Δ-resonance will be briefly mentioned. In the following section some points refering to the pion production in a relativistic heavy ion collision will be discussed. In addition, the basic ideas of the applied models will be shown. In the last part results from existing experiments and possible interpretations will be presented. (orig.)

  17. Hydrogen atom model for nucleon and pion

    International Nuclear Information System (INIS)

    Baiquni, A.

    1976-01-01

    Discussion on Dion as double charge particle, covering that on semi classical model, proton Dionium model consequence, symmetry group in hydrogen, hydrogen atom dynamic group, and discussion on relativistic dynamic group, covering relativistic equation for hydrogen, operator extension of SO(4, 2), application of SO(4,2)O SO(4,2), and hydrogen complete equation, are given. (author)

  18. Progress on using deuteron-deuteron fusion generated neutrons for 40Ar/39Ar sample irradiation

    Science.gov (United States)

    Rutte, Daniel; Renne, Paul R.; Becker, Tim; Waltz, Cory; Ayllon Unzueta, Mauricio; Zimmerman, Susan; Hidy, Alan; Finkel, Robert; Bauer, Joseph D.; Bernstein, Lee; van Bibber, Karl

    2017-04-01

    We present progress on the development and proof of concept of a deuteron-deuteron fusion based neutron generator for 40Ar/39Ar sample irradiation. Irradiation with deuteron-deuteron fusion neutrons is anticipated to reduce Ar recoil and Ar production from interfering reactions. This will allow dating of smaller grains and increase accuracy and precision of the method. The instrument currently achieves neutron fluxes of ˜9×107 cm-2s-1 as determined by irradiation of indium foils and use of the activation reaction 115In(n,n')115mIn. Multiple foils and simulations were used to determine flux gradients in the sample chamber. A first experiment quantifying the loss of 39Ar is underway and will likely be available at the time of the presentation of this abstract. In ancillary experiments via irradiation of K salts and subsequent mass spectrometric analysis we determined the cross-sections of the 39K(n,p)39Ar reaction at ˜2.8 MeV to be 160 ± 35 mb (1σ). This result is in good agreement with bracketing cross-section data of ˜96 mb at ˜2.45 MeV and ˜270 mb at ˜4 MeV [Johnson et al., 1967; Dixon and Aitken, 1961 and Bass et al. 1964]. Our data disfavor a much lower value of ˜45 mb at 2.59 MeV [Lindström & Neuer, 1958]. In another ancillary experiment the cross section for 39K(n,α)36Cl at ˜2.8 MeV was determined as 11.7 ± 0.5 mb (1σ), which is significant for 40Ar/39Ar geochronology due to subsequent decay to 36Ar as well as for the determination of production rates of cosmogenic 36Cl. Additional experiments resolving the cross section functions on 39K between 1.5 and 3.6 MeV are on their way using the LICORNE neutron source of the IPN Orsay tandem accelerator. Results will likely be available at the time of the presentation of this abstract. While the neutron generator is designed for fluxes of ˜109 cm-2s-1, arcing in the sample chamber currently limits the power—straightforwardly correlated to the neutron flux—the generator can safely be run at. Further

  19. A new generation of medical cyclotrons for the 90's

    International Nuclear Information System (INIS)

    Milton, B.F.

    1995-08-01

    Cyclotrons continue to be efficient accelerators for use in radio-isotope production. In recent years, developments in accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicates a strong future for commercial cyclotrons. In this paper the authors will survey recent developments in the areas of cyclotron technology as they relate to the new generation of commercial cyclotrons. Existing and potential markets for these cyclotrons will be presented. They will also discuss the possibility of systems capable of extracted energies up to 150 MeV and extracted beam currents of up to 2.0 mA

  20. A new generation of medical cyclotrons for the 90's

    International Nuclear Information System (INIS)

    Milton, B.F.

    1995-08-01

    Cyclotrons continue to be efficient accelerators for use in radio-isotope production. In recent years, developments in accelerator technology have greatly increased the practical beam current in these machines while also improving the overall system reliability. These developments combined with the development of new isotopes for medicine and industry, and a retiring of older machines indicates a strong future for commercial cyclotrons. In this paper we will survey recent developments in the areas of cyclotron technology as they relate to the new generation of commercial cyclotrons. Existing and potential markets for these cyclotrons will be presented. We will also discuss the possibility of systems capable of extracted energies up to 150 MeV and extracted beam currents of up to 2.0 mA. (author)

  1. Gas generation from the irradiation of mortar

    International Nuclear Information System (INIS)

    Lewis, M.A.; Warren, D.W.

    1989-01-01

    A mortar formulation capable of immobilizing chloride salts with high levels of radioactivity is being developed. As part of the developmental effort, radiation effects are being investigated. The radiolytic generation of gas(es) from irradiated mortar formulations was determined for several formulations with variable salt loadings at several test temperatures. The irradiation of a mortar formulation consisting of cement, slag, fly ash, water and 0 to 10 wt % salt led to the generation of hydrogen. The rate of generation was approximately constant, steady state pressures were not attained and final pressures were comparatively high. Higher salt concentrations were correlated with higher hydrogen generation rates for experiments at ambient temperature while lower rates were observed at 120/degree/C. The irradiation of a mortar consisting of cement, fly ash, water and salt led to the radiolytic generation of both oxygen and hydrogen. The addition of 2 wt % FeS or CaS inhibited oxygen generation and changed the hydrogen production rate. 10 refs., 4 figs., 3 tabs

  2. A superconducting radio-frequency cavity for manipulating the phase space of pion beams at LAMPF

    Energy Technology Data Exchange (ETDEWEB)

    O' Donnell, J.M.; Davis, J.; DeHaven, R.A.; Gray, E.; Johnson, R.; Lomax, R.E.; McCloud, B.J.; McGill, J.A.; Morris, C.L.; Novak, J.; Rusnak, B.; Tubb, G. (Los Alamos National Lab., Los Alamos, NM (United States)); Applegate, J.M.; Averett, T.D.; Beck, J.; Ritchie, B.G. (Arizona State Univ., Tempe, AZ (United States)); Haebel, E. (CERN, Geneva (Switzerland)); Kiehlmann, D.; Klein, U.; Peniger, M.; Schaefer, P.; Vogel, H. (Siemens AG, Accelerator and Magnet Technology, Bergisch Gladbach (Germany)); Ward, H.; Moore, C.F. (Univ. of Texas, Austin, TX (United States))

    1992-07-15

    The SCRUNCHER is a superconducting radio-frequency cavity for manipulating the longitudinal phase space of the secondary pion beam from the low energy pion channel at LAMPF. Test results of the cavity performance and initial results from in-beam tests are presented. (orig.).

  3. A superconducting radio-frequency cavity for manipulating the phase space of pion beams at LAMPF

    Science.gov (United States)

    O'Donnell, J. M.; Davis, J.; DeHaven, R. A.; Gray, E.; Johnson, R.; Lomax, R. E.; McCloud, B. J.; McGill, J. A.; Morris, C. L.; Novak, J.; Rusnak, B.; Tubb, G.; Applegate, J. M.; Averett, T. D.; Beck, J.; Ritchie, B. G.; Haebel, E.; Kiehlmann, D.; Klein, U.; Peiniger, M.; Schäfer, P.; Vogel, H.; Ward, H.; Fred Moore, C.

    1992-07-01

    The SCRUNCHER is a superconducting radio-frequency cavity for manipulating the longitudinal phase space of the secondary pion beam from the low energy pion channel at LAMPF. Test results of the cavity performance and initial results from in-beam tests are presented.

  4. Where to look for pion condensation in heavy ion collisions

    International Nuclear Information System (INIS)

    Pirner, H.J.

    1994-08-01

    The possibility to observe a pion condensate in peripheral nucleus-nucleus collisions at GSI energies is discussed. A condensate may be observed via pronounced peaks in pion production in a narrow region of momenta k perpendicular to ≅(2-3)m π corresponding to rather large rapidity values. (orig.)

  5. Invariant potential for elastic pion--nucleus scattering. Technical report No. 75-075

    International Nuclear Information System (INIS)

    Cammarata, J.B.; Banerjee, M.K.

    1975-04-01

    From the Wick-Dyson expansion of the exact propagator of a pion in the presence of a nucleus an invariant potential for crossing symmetric, elastic pion-nucleus scattering is obtained in terms of a series of pion-nucleon diagrams. The Chew-Low theory is used to develop a model in which the most important class of diagrams is effectively summed. Included in this model is the Exclusion Principle restriction on the pion-bound nucleon interaction, the effects of the binding of nucleons, a kinematic transformation of energy from the lab to the πN center of mass frames, and the Fermi motion and recoil of the target nucleons. From a numerical study of the effects of these processes on the π- 12 C total cross section, the relative importance of each is determined. Other processes contributing to the elastic scattering of pions not included in the present model are also discussed. (9 figures) (U.S.)

  6. Rheological analysis of irradiated crosslinkable and scissionable polymers used for medical devices under different radiation conditions

    Science.gov (United States)

    Satti, A. J.; Ressia, J. A.; Cerrada, M. L.; Andreucetti, N. A.; Vallés, E. M.

    2018-03-01

    The effects on different synthetic polymers of distinct types of radiation, gamma rays and electron beam, under different atmospheres are followed by changes in their viscoelastic behavior. Taking into account the two main radioinduced reactions, crosslinking and scissioning of polymeric chains, liquid polydimethylsiloxane has been used as example of crosslinkable polymer and semi crystalline polypropylene as example of scissionable polymer. Propylene - 1-hexene copolymers have been also evaluated, and the effects of both reactions were clearly noticed. Accordingly, samples of those aforementioned polymers have been irradiated with 60Co gamma irradiation in air and under vacuum, and also with electron beam, at similar doses. Sinusoidal dynamic oscillation experiments showed a significant increase in branching and crosslinking reactions when specimens are irradiated under vacuum, while scissioning reactions were observed for the different polymers when irradiation takes place under air with either gamma irradiation or electron beam.

  7. The pion: an enigma within the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Tanja; Roberts, Craig D.

    2016-05-27

    Almost 50 years after the discovery of gluons & quarks, we are only just beginning to understand how QCD builds the basic bricks for nuclei: neutrons, protons, and the pions that bind them. QCD is characterised by two emergent phenomena: confinement & dynamical chiral symmetry breaking (DCSB). They are expressed with great force in the character of the pion. In turn, pion properties suggest that confinement & DCSB are closely connected. As both a Nambu-Goldstone boson and a quark-antiquark bound-state, the pion is unique in Nature. Developing an understanding of its properties is thus critical to revealing basic features of the Standard Model. We describe experimental progress in this direction, made using electromagnetic probes, highlighting both improvements in the precision of charged-pion form factor data, achieved in the past decade, and new results on the neutral-pion transition form factor. Both challenge existing notions of pion structure. We also provide a theoretical context for these empirical advances, first explaining how DCSB works to guarantee that the pion is unnaturally light; but also, nevertheless, ensures the pion is key to revealing the mechanisms that generate nearly all the mass of hadrons. Our discussion unifies the charged-pion elastic and neutral-pion transition form factors, and the pion's twist-2 parton distribution amplitude. It also indicates how studies of the charged-kaon form factor can provide significant contributions. Importantly, recent predictions for the large-$Q^2$ behaviour of the pion form factor can be tested by experiments planned at JLab 12. Those experiments will extend precise charged-pion form factor data to momenta that can potentially serve in validating factorisation theorems in QCD, exposing the transition between the nonperturbative and perturbative domains, and thereby reaching a goal that has long driven hadro-particle physics.

  8. Gamma irradiation test report of simulated grout specimens for gas generation/liquid advection

    International Nuclear Information System (INIS)

    Hinman, C.A.

    1994-01-01

    This report presents the results from an irradiation test performed on four specimens of grout that were fabricated from synthetic Double Shell Slurry Feed (DSSF) liquid waste. The objective was to investigate the radiolytic generation of gases and the potential for advective rejection of waste liquids from the grout matrix and to provide experimental information for the validation of the C-Cubed calculated model. It has been demonstrated that a number of gases can be formed within the grout due to radiolytic decomposition of various chemical components that make up the grout. This observation leads to the conjecture that the potential exists for the rejection of a portion of the 60 vol% free liquid from the grout matrix driven by pressurization by these gases. It was found that, for the specimen geometries used in this test series, and for peak radiation dose accumulation rates on the order of 4 to 60 times of the initial rate expected in the grout vaults (300 Rads/hr), no liquid rejection was observed from 2% to 35% of the target exposure expected in the grout vaults (1E+08 Rads). When the irradiation rate exceeded the projected grout vault dose rate by a factor of 200 a small amount of liquid rejection was observed from one of two specimens that had received 20% more than the goal exposure. Because of the differences in the magnitudes of the relative radiation field strengths between this study and an actual grout vault, it is concluded that the potential for liquid rejection by internal gas pressurization from presently configured grout waste forms is very low for the expected conditions

  9. Electron beam ion sources for use in second generation synchrotrons for medical particle therapy

    Science.gov (United States)

    Zschornack, G.; Ritter, E.; Schmidt, M.; Schwan, A.

    2014-02-01

    Cyclotrons and first generation synchrotrons are the commonly applied accelerators in medical particle therapy nowadays. Next generation accelerators such as Rapid Cycling Medical Synchrotrons (RCMS), direct drive accelerators, or dielectric wall accelerators have the potential to improve the existing accelerator techniques in this field. Innovative accelerator concepts for medical particle therapy can benefit from ion sources which meet their special requirements. In the present paper we report on measurements with a superconducting Electron Beam Ion Source, the Dresden EBIS-SC, under the aspect of application in combination with RCMS as a well proven technology. The measurements indicate that this ion source can offer significant advantages for medical particle therapy. We show that a superconducting EBIS can deliver ion pulses of medically relevant ions such as protons, C4 + and C6 + ions with intensities and frequencies required for RCMS [S. Peggs and T. Satogata, "A survey of Hadron therapy accelerator technology," in Proceedings of PAC07, BNL-79826- 2008-CP, Albuquerque, New Mexico, USA, 2007; A. Garonna, U. Amaldi et al., "Cyclinac medical accelerators using pulsed C6 +/H+_2 ion sources," in Proceedings of EBIST 2010, Stockholm, Sweden, July 2010]. Ion extraction spectra as well as individual ion pulses have been measured. For example, we report on the generation of proton pulses with up to 3 × 109 protons per pulse and with frequencies of up to 1000 Hz at electron beam currents of 600 mA.

  10. Crystal physics with positive pions

    International Nuclear Information System (INIS)

    Flik, G.

    1983-01-01

    The π + /μ + lattice channeling is a new method of investigation in solid state physics. In the present thesis axial and planar channeling effects could be observed for the first time in monocrystalline Tantalum for 4, 12 MeV Muons generated by the decay of implanted positive pions. It is found that pions for T + /μ + channeling is investigated in Germanium for low temperatures. For T > 80 K tetrahedral sites are found, but for T < 80 K hexaedral sites or sites in the middle of the Ge-Ge bond are preferred. (BHO)

  11. Multiple-collision model for pion production in relativistic nucleus-nucleus collisions

    International Nuclear Information System (INIS)

    Vary, J.P.

    1978-01-01

    A simple model for pion production in relativistic heavy-ion collisions is developed based on nucleon-nucleon data, nuclear density distribution, and the assumption of straight-line trajectories. Multiplicity distributions for total pion production and for negative-pion production are predicted for 40 Ar incident on a Pb 3 O 4 target at 1.8 GeV/nucleon. Production through intermediate baryon resonances reduces the high-multiplicity region but insufficiently to yield agreement with data. This implies the need for a coherent production mechanism

  12. Development of a cooling system and vacuum chamber for the pion tracker for HADES

    Energy Technology Data Exchange (ETDEWEB)

    Wirth, Joana [Technische Univ. Muenchen, Garching (Germany). Excellence Cluster Universe; Collaboration: HADES-Collaboration

    2013-07-01

    One of the future experiments planned at SIS18 with the HADES spectrometer in GSI Darmstadt envisages the employment of pion beam colliding on LH2 or nuclear target. Due to the fact that secondary pion beam has high momentum spread, since the precise knowledge of pion momentum is mandatory to carry out the planned exclusive measurements, we have to measure the momentum for each individual pion. For this purpose our group is developing a pion beam tracking system, which consists of two silicon detectors. Both detectors are located in the beamline and therefore have to cope the high-intensity secondary beam. Cooling of a silicon detector strongly improves its radiation hardness and performance. It reduces the leakage current and thus the noise, which is important for the detection of MIPs like pions. We have designed and built a complete prototype system of vacuum chamber and detector cooling. With use of the Finite Element Method we simulated the mechanical and thermal properties of the prototype. The proposed poster shows the current status and performance of the cooling system for a test-detector, focusing on the reduction of the leakage current and the noise.

  13. A final state interaction model for K and eta decay into three pions

    International Nuclear Information System (INIS)

    Angus, A.G.

    1973-07-01

    The Khuri-Treiman model is adapted in a relativistic formalism with the electromagnetic mass differences of the pions in the final state taken into account to produce new predictions for the relative decay rates and the slope parameters of the four reactions K→3x and the two reactions eta→3x. The pion-pion interaction is investigated in terms of the N/D method and as well as the normal pure pole approximations for the N functions. The Khuri-Treiman equations are solved for the best solutions from both the pure pole and the mixed pole and cut models. (author)

  14. The irradiation of volunteers in medical research

    International Nuclear Information System (INIS)

    Rae, S.

    1976-01-01

    Attempts to produce guidelines for use in medical research involving the irradiation of volunteers are surveyed. The recommendations of the British Institute of Radiology (Irradiation of Human Subjects for Medical Research, Bull. Brit. Radiology, 1975, vol.1, no.2, 4) are summarized. These recommendations, based on a preliminary working document produced by the World Health Organization, are considered in three parts, the selection of subjects, the categorisation and the approval of research projects. The importance of freely given and informed consent is emphasized. The suggested four categories of project are classified by the amount of total body radiation to be received by the subject in each project, and the necessary assessment and prior approval procedures are related to this classification. The imposition of a lifetime exposure limit is compared with occupational exposures which are assessed on an annual basis, and the ICRP's 'planned special exposures'. Repeated irradiation of the same subject, although permissible within the recommended limits, may create difficulties. The total lifetime accumulated dose may not always be immediately available if the subject has worked in a number of different establishments. The possibility of compiling an approved list of procedures to reduce some of the anticipated delays in processing applications is discussed. (author)

  15. One-pion exchange current corrections for nuclear magnetic moments in relativistic mean field theory

    International Nuclear Information System (INIS)

    Li Jian; Yao, J.M.; Meng Jie; Arima, Akito

    2011-01-01

    The one-pion exchange current corrections to isoscalar and isovector magnetic moments of double-closed shell nuclei plus and minus one nucleon with A = 15, 17, 39 and 41 have been studied in the relativistic mean field (RMF) theory and compared with previous relativistic and non-relativistic results. It has been found that the one-pion exchange current gives a negligible contribution to the isoscalar magnetic moments but a significant correction to the isovector ones. However, the one-pion exchange current enhances the isovector magnetic moments further and does not improve the corresponding description for the concerned nuclei in the present work. (author)

  16. Generation and scaling behaviour of high-energy pions in relativistic heavy ion reactions

    International Nuclear Information System (INIS)

    Riess, F.

    1979-12-01

    Calculations with the help of a collision approximation as carried out in this study, are certainly linked with many uncertainties. The different forms of pulse distributions and cross sections used cover however such a broad region of possibilities, that even detailed calculations will not give any results essentially deviating from those obtained here. The various assumptions and statements could be relatively easily investigated using the collision approximation. Hence the above-mentioned aim, to pick out the principal information from the statement is achieved. It was shown that taking the two assumptions - nucleon-nucleon collisions only and - consideration of a cluster effect, in both cases the experimental results for a given reaction can be well reproduced as long as one only regards one projectile energy. It is important in the first case that the pulse distribution in the region of 0,5 to 1 GeV/c contains sufficiently large components - a simple Gauss distribution with a 'normal' parameter from nuclean physics is not sufficient here. The cluster statement provides the high-energy pions through the changed kinematics, compared to pure nucleon-nucleon collisions, and through the greater energy provided by a cluster in the reaction. (orig./HSI) [de

  17. Generative Interpretation of Medical Images

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille

    2004-01-01

    This thesis describes, proposes and evaluates methods for automated analysis and quantification of medical images. A common theme is the usage of generative methods, which draw inference from unknown images by synthesising new images having shape, pose and appearance similar to the analysed images......, handling of non-Gaussian variation by means of cluster analysis, correction of respiratory noise in cardiac MRI, and the extensions to multi-slice two-dimensional time-series and bi-temporal three-dimensional models. The medical applications include automated estimation of: left ventricular ejection...

  18. Rare pion and kaon decays

    International Nuclear Information System (INIS)

    Bryman, D.

    1983-09-01

    Some rare pion and kaon decays, which provide clues to the generation puzzle, are discussed. The π→ eν/π→μ/ν branching ratio test of universality and the status of searches for K + → π + rho anti rho are reviewed

  19. Applicability of perturbative QCD and NLO power corrections for the pion form factor

    International Nuclear Information System (INIS)

    Yeh Tsungwen

    2002-01-01

    As is well recognized, the asymptotic of the perturbative QCD prediction for the pion form factor is much smaller than the upper end of the data. We investigate this problem. We first evaluate the next-to-leading-order (NLO) power correction for the pion form factor. The corrected form factor contains nonperturbative parameters which are determined from a χ 2 fit to the data. Interpreting these parameters leads to the fact that the involved strong interaction coupling constant should be identified as an effective coupling constant under a nonperturbative QCD vacuum. If the scale associated with the effective coupling constant is identified as 2 Q 2 , then Q 2 , the momentum transfer square for the pion form factor to be measured, can have a value about 1 GeV 2 , and , the averaged momentum fraction variable, can locate around 0.5. This circumstance is consistent with the asymptotic model for the pion wave function

  20. Pion Production Measurement in NA61/SHINE Experiment for High Precision Neutrino Oscillation Experiments

    CERN Document Server

    Palczewski, Tomasz Jan

    2009-01-01

    One of physics goals of the NA61/SHINE experiment is a measurement of hadron production cross sections from proton-Carbon interactions at 31GeV/c for the T2K experiment at J-PARC. A precise knowledge of differential cross sections for pion and kaon production is of importance for improving the accuracy of neutrino flux simulations. The NA61 detector has a large angular acceptance, full coverage of the T2K phase space region, and good particle identification. In this work the analyses of negatively charged pion production are presented. Two different methods of negative pion selection and corrections for detector effects are discussed. Finally, preliminary dn/dp distributions of negatively charged pion in p+C interactions at 31 GeV/c are presented.

  1. Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Gutzwiller, Simone

    2012-10-08

    In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32{sup 3} x 64 and a 40{sup 3} x 64 lattice with N{sub f}=2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.

  2. Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD

    International Nuclear Information System (INIS)

    Gutzwiller, Simone

    2012-01-01

    In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32 3 x 64 and a 40 3 x 64 lattice with N f =2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.

  3. Medical waste irradiation study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Adler, R.J.; Stein, J. [North Star Research Corp., Albuquerque, NM (United States); Nygard, J. [Advance Bio-Control (United States)

    1998-07-25

    The North Star Research Corporation Medical Waste project is described in this report, with details of design, construction, operation, and results to date. The project began with preliminary design of the accelerator. The initial design was for a single accelerator chamber with a vacuum tube cavity driver built into the chamber itself, rather than using a commercial tube separate from the RF accelerator. The authors believed that this would provide more adjustability and permit better coupling to be obtained. They did not have sufficient success with that approach, and finally completed the project using a DC accelerator with a unique new scanning system to irradiate the waste.

  4. Medical waste irradiation study. Final report

    International Nuclear Information System (INIS)

    Adler, R.J.; Stein, J.; Nygard, J.

    1998-01-01

    The North Star Research Corporation Medical Waste project is described in this report, with details of design, construction, operation, and results to date. The project began with preliminary design of the accelerator. The initial design was for a single accelerator chamber with a vacuum tube cavity driver built into the chamber itself, rather than using a commercial tube separate from the RF accelerator. The authors believed that this would provide more adjustability and permit better coupling to be obtained. They did not have sufficient success with that approach, and finally completed the project using a DC accelerator with a unique new scanning system to irradiate the waste

  5. Investigation of pion-treated human skin nodules for therapeutic gain

    International Nuclear Information System (INIS)

    Kligerman, M.M.; Sala, J.M.; Wilson, S.; Yuhas, J.M.

    1978-01-01

    A patient with multiple metastatic tumor nodules in the skin, from a primary breast carcinoma, was treated with graded doses of pions and x rays to establish skin tolerance. She was followed up for 346 days, permitting observation of time to regrowth of the tumor nodules. All 16 of these had disappeared after treatment, without significant correlation with type of radiation or dose, or with nodule size. However, time to regrowth depended both on the type and the dose of radiation. Earlier, relative biological effectiveness (RBE), was established at 1.42 for acute skin injury. Using this RBE to normalize doses of pions and x rays causing equivalent acute skin injury, and plotting those doses vs time to regrowth of tumor nodules, yielded a therapeutic gain (37.5%) in favor of pions. No late skin or subcutaneous tissue changes were seen, and no qualitative difference between pions and x rays in late skin effects was observed

  6. Search for rare muon and pion decay modes with the Crystal Box detector

    International Nuclear Information System (INIS)

    Hoffman, C.M.; Bolton, R.D.; Bowman, J.D.

    1986-01-01

    New experimental upper limits for the branching ratios of the lepton-family-number nonconserving decays μ + → e + γ and μ + → e + γγ are presented. A new determination of γ, the ratio of pion axial-vector to vector form factors, from radiative pion decay is also reported. These results are from data taken with the Crystal Box detector at LAMPF

  7. Search for rare muon and pion decay modes with the crystal box detector

    International Nuclear Information System (INIS)

    Piilonen, L.E.; Bolton, R.D.; Bowman, J.D.

    1986-01-01

    New experiental upper limits for the branching ratios of the lepton-family-number nonconserving decays μ + → e + γ and μ + → e + γγ are presented. A new determination of γ, the ratio of pion axial vector to vector form factors, from radiative pion decay is also reported. These results are from data taken with the Crystal Box detector at LAMPF. 11 refs., 7 figs

  8. Roy-Steiner equations for pion-nucleon scattering

    Science.gov (United States)

    Ditsche, C.; Hoferichter, M.; Kubis, B.; Meißner, U.-G.

    2012-06-01

    Starting from hyperbolic dispersion relations, we derive a closed system of Roy-Steiner equations for pion-nucleon scattering that respects analyticity, unitarity, and crossing symmetry. We work out analytically all kernel functions and unitarity relations required for the lowest partial waves. In order to suppress the dependence on the high energy regime we also consider once- and twice-subtracted versions of the equations, where we identify the subtraction constants with subthreshold parameters. Assuming Mandelstam analyticity we determine the maximal range of validity of these equations. As a first step towards the solution of the full system we cast the equations for the π π to overline N N partial waves into the form of a Muskhelishvili-Omnès problem with finite matching point, which we solve numerically in the single-channel approximation. We investigate in detail the role of individual contributions to our solutions and discuss some consequences for the spectral functions of the nucleon electromagnetic form factors.

  9. Reaching Our Successors: Millennial Generation Medical Students ...

    African Journals Online (AJOL)

    ... life as a plastic surgeon and the ability of plastic surgeons to provide good role models for medical students. Female medical students were more concerned with gender equity and work-life balance in selecting plastic surgery compared to male medical students. Keywords: Career, medical students, millennial generation, ...

  10. Neural network radiative transfer solvers for the generation of high resolution solar irradiance spectra parameterized by cloud and aerosol parameters

    International Nuclear Information System (INIS)

    Taylor, M.; Kosmopoulos, P.G.; Kazadzis, S.; Keramitsoglou, I.; Kiranoudis, C.T.

    2016-01-01

    This paper reports on the development of a neural network (NN) model for instantaneous and accurate estimation of solar radiation spectra and budgets geared toward satellite cloud data using a ≈2.4 M record, high-spectral resolution look up table (LUT) generated with the radiative transfer model libRadtran. Two NN solvers, one for clear sky conditions dominated by aerosol and one for cloudy skies, were trained on a normally-distributed and multiparametric subset of the LUT that spans a very broad class of atmospheric and meteorological conditions as inputs with corresponding high resolution solar irradiance target spectra as outputs. The NN solvers were tested by feeding them with a large (10 K record) “off-grid” random subset of the LUT spanning the training data space, and then comparing simulated outputs with target values provided by the LUT. The NN solvers demonstrated a capability to interpolate accurately over the entire multiparametric space. Once trained, the NN solvers allow for high-speed estimation of solar radiation spectra with high spectral resolution (1 nm) and for a quantification of the effect of aerosol and cloud optical parameters on the solar radiation budget without the need for a massive database. The cloudy sky NN solver was applied to high spatial resolution (54 K pixel) cloud data extracted from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard the geostationary Meteosat Second Generation 3 (MSG3) satellite and demonstrated that coherent maps of spectrally-integrated global horizontal irradiance at this resolution can be produced on the order of 1 min. - Highlights: • Neural network radiative transfer solvers for generation of solar irradiance spectra. • Sensitivity analysis of irradiance spectra with respect to aerosol and cloud parameters. • Regional maps of total global horizontal irradiance for cloudy sky conditions. • Regional solar radiation maps produced directly from MSG3/SEVIRI satellite inputs.

  11. Precise tests for the unitarized pion photoproduction impulse amplitude in exclusive nuclear reactions

    International Nuclear Information System (INIS)

    Wittman, R.

    1986-07-01

    An impulse amplitude for pion photoproduction, suitable for the nuclear problem, is constructed with improved background dynamics and unitarity. The superior features of the amplitude are demonstrated at energies between threshold (E/sub γ/ = 150 MeV) and the Δ(1232) resonance energy (E/sub γ/ = 320 MeV) by discussing their effects on partial cross sections relevant to exclusive transitions in the 1p-shell. The specific reactions of 13 C(γ,π - ) 13 N/sub g.s./ and 14 N(γ,π + ) 14 C/sub g.s./ are discussed in light of these more general partial cross sections. The nuclear structure of the A = 14 system helps to enhance the effects considered. At or near resonance, very sizable (20 to 30%) effects arise both from the unitarity and from the refined treatment of the pionic final state interaction generated in the Δ-hole approach. Other examples of charged pion photoproduction reactions for 1p-shell nuclei are discussed briefly. Future theoretical improvements and experimental possibilities are suggested. 61 refs., 58 figs

  12. Reconciling threshold and subthreshold expansions for pion-nucleon scattering

    Science.gov (United States)

    Siemens, D.; Ruiz de Elvira, J.; Epelbaum, E.; Hoferichter, M.; Krebs, H.; Kubis, B.; Meißner, U.-G.

    2017-07-01

    Heavy-baryon chiral perturbation theory (ChPT) at one loop fails in relating the pion-nucleon amplitude in the physical region and for subthreshold kinematics due to loop effects enhanced by large low-energy constants. Studying the chiral convergence of threshold and subthreshold parameters up to fourth order in the small-scale expansion, we address the question to what extent this tension can be mitigated by including the Δ (1232) as an explicit degree of freedom and/or using a covariant formulation of baryon ChPT. We find that the inclusion of the Δ indeed reduces the low-energy constants to more natural values and thereby improves consistency between threshold and subthreshold kinematics. In addition, even in the Δ-less theory the resummation of 1 /mN corrections in the covariant scheme improves the results markedly over the heavy-baryon formulation, in line with previous observations in the single-baryon sector of ChPT that so far have evaded a profound theoretical explanation.

  13. Development of a cooling system and vacuum chamber for the pion tracker for HADES

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Tobias [TU Muenchen, James-Franck-Strasse, D-85748 Garching (Germany); Collaboration: HADES-Collaboration

    2014-07-01

    One of the future experiments planned at SIS18 with the HADES spectrometer in GSI Darmstadt envisages the employment of a pion beam colliding on a LH2 or a nuclear target. Due to the fact that the secondary pion beam has a high momentum spread, the momentum for each individual pion has to be measured for the planned exclusive measurements. For this purpose our group develops a pion tracking system, consisting of two double sided striped silicon detectors. Both will be located at different positions in the beamline in front of the HADES experiment, therefore they have to deal with high particle rates. Considering the detection of pions (MIPs), the noise of the detectors has to have a very small level. This can be achieved by cooling. For now the final version of the detector chamber and cooling system has been built and is currently tested. The proposed poster shows the current status and performance of the cooling system for the silicon detector, focusing on the reduction of the leakage current and the noise.

  14. Magnetic polarizability of pion

    Energy Technology Data Exchange (ETDEWEB)

    Luschevskaya, E.V., E-mail: luschevskaya@itep.ru [Institute for Theoretical and Experimental Physics, Bolshaia Cheremushkinskaia 25, 117218 Moscow (Russian Federation); School of Biomedicine, Far Eastern Federal University, 690950 Vladivostok (Russian Federation); Solovjeva, O.E., E-mail: olga.solovjeva@itep.ru [Institute for Theoretical and Experimental Physics, Bolshaia Cheremushkinskaia 25, 117218 Moscow (Russian Federation); Teryaev, O.V., E-mail: teryaev@theor.jinr.ru [Joint Institute for Nuclear Research, Dubna, 141980 (Russian Federation); National Research Nuclear University “MEPhI” (Moscow Engineering Physics Institute), Kashirskoe highway, 31, 115409 Moscow (Russian Federation)

    2016-10-10

    We explore the energy dependence of π mesons off the background Abelian magnetic field on the base of quenched SU(3) lattice gauge theory and calculate the magnetic dipole polarizability of charged and neutral pions for various lattice volumes and lattice spacings. The contribution of the magnetic hyperpolarizability to the neutral pion energy has been also found.

  15. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  16. Current algebra and soft pion theorems for weak π production

    International Nuclear Information System (INIS)

    Adler, S.L.

    1976-01-01

    Beginning with definitions of vector, scalar, axial vector, pseudoscalar, and tensor current densities, equal time current commutators are derived and divergences are discussed. The partially conserved axial current (PCAC) hypothesis is formulated and used to derive the Goldberger--Treiman relation. Current algebra and the PCAC hypothesis are then employed to develop a master formula describing the reaction J + N → π + N where J is a current with four momentum k, and π is a soft pion with four momentum q. Several applications are considered: πN scattering consistency conditions, π isovector electroproduction relations, π production by an isoscalar weak neutral current, π axial vector weak production relations, and low energy theorems which combine soft pion results with knowledge of divergences of the vector or axial vector current J (which induces weak pion production). It is concluded that (1) the entire weak production amplitude is determined to zero order in q by soft pion theorems, and (2) combined relations determine corrections linear in q but of zero order in k

  17. Pion production cross sections and associated parameters

    International Nuclear Information System (INIS)

    Bradbury, J.N.

    1985-01-01

    Negative pions have been used for radiotherapy at the meson factories LAMPF (USA), SIN (Switzerland), and TRIUMF (Canada) and have been planned for use at new meson facilities under construction (USSR) and at proposed dedicated medical facilities. Providing therapeutically useful dose rates of pions requires a knowledge of the pion production cross sections as a function of primary proton energy (500 to 1000 MeV), pion energy (less than or equal to100 MeV), production angle, and target material. The current status of the data base in this area is presented including theoretical guidelines for extrapolation purposes. The target material and geometry, as well as the proton and pion beam parameters, will affect the electron (and muon) contamination in the beam which may have an important effect on both the LET characteristics of the dose and the dose distribution. In addition to cross-section data, channel characteristics such as length of pion trajectory, solid-angle acceptance, and momentum analysis will affect dose rate, distribution, and quality. Such considerations are briefly addressed in terms of existing facilities and proposed systems. 16 refs., 6 figs

  18. The expanding pion liquid and the pion spectra

    International Nuclear Information System (INIS)

    Ayala, A.

    1999-01-01

    We compute the pion inclusive momentum distribution in heavy-ion collisions for energies at the Alternating Gradient Synchrotron (AGS), assuming thermal equilibrium and accounting for density and expansion effects at freeze out. We compare to data on mid-rapidity charged pions produced in central Au + Au collisions and find a very good agreement. The shape of the distribution at low transverse mass is explained in part as an effect arising from the high mean pion density achieved in these reactions. The difference between the positive and negative pion distributions in the same region is attributed in part to the different average yields of each kind of charged pions. (Author)

  19. Compact Neutron Generators for Medical, Home Land Security, and Planetary Exploration

    CERN Document Server

    Reijonen, Jani

    2005-01-01

    The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0 - 9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration in form of neutron based, sub-surface hydrogen detection systems. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Three main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-c...

  20. Beam Spin Asymmetry Measurements for Two Pion Photoproduction at CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Mark D. [Univ. of Glasgow, Scotland (United Kingdom)

    2015-09-01

    The overarching goal of this analysis, and many like it, is to develop our understanding of the strong force interactions within the nucleon by examining the nature of their excitation spectra. As the resonances of these spectra have very short lifetimes (tau = 1x10-23 s) and often have very similar masses, it is often impossible to directly observe resonances in the excitation spectra of nucleons. Polarization observables allow us to study the resonances by looking at how they affect the spin state of final state particles. The beam asymmetry is a polarization observable that allows us to detect the sensitivity of these resonances, and other transition mechanisms, to the electric vector orientation of incident photons. Presented in this thesis are first measurements of the beam asymmetries in the resonant region for the reaction channel pgamma p --> p π+ π-focusing on the intermediate mesonic states rho^0 and f^0, and the final state pions. The analysis used data from the g8b experiment undertaken at the Thomas Jefferson National Accelerator Facility (JLab), the first experiment at JLab to use a linearly polarized photon beam. Using the coherent Bremsstrahlung facility and the CLAS detector of Hall B at JLab allowed for many multi-channel reactions to be detected and the first measurements of many polarization observables including those presented here. A brief overview of the theoretical framework used to undertake this analysis is given, followed by a description of the experimental details of the facilities used, then a description of the calibration of the Bremsstrahlung tagging facility which the author undertook, and finally the analysis is presented and the resulting measurements.

  1. Assessment of differences between X and γ rays in order to validate a new generation of irradiators for insect sterilization

    International Nuclear Information System (INIS)

    Mastrangelo, Thiago; Walder, Julio M.M.; Parker, Andrew G.; Jessup, Andrew; Orozco-Davila, Dina; Islam, Amirul; Dammalage, Thilakasiri; Pereira, Rui

    2009-01-01

    Recent fears of terrorism provoked an increase in delays and denials of transboundary shipments of radioisotopes. This represents a serious constraint to sterile insect technique (SIT) programs around the world as they rely on the use of ionizing energy from radioisotopes for insect sterilization. In order to validate a novel Xray irradiator, a series of studies on Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) were carried out, comparing the relative biological effectiveness (RBE) between X-rays and traditional γ radiation from 60 Co. Male C. capitata pupae and pupae of both sexes of A. fraterculus, both 24 to 48 h before adult emergence, were irradiated with doses ranging from 15 to 120 Gy and 10 to 70 Gy respectively. Estimated mean doses of 91.2 Gy of X and 124.9 Gy of γ radiation induced 99% sterility in C. capitata males. Irradiated A. fraterculus were 99% sterile at about 40-60 Gy for both radiation treatments. Standard quality control parameters were not significantly affected by the two types of radiation. There were no significant differences between X and γ radiation regarding mating indices. The RBE did not differ significantly between the tested X and γ radiation, and X-rays are as biologically effective for SIT purposes as γ rays are. This work confirms the suitability of this new generation of X-ray irradiators for pest control programs in UN Member States. (author)

  2. Soft-Pion theorems for large scale structure

    International Nuclear Information System (INIS)

    Horn, Bart; Hui, Lam; Xiao, Xiao

    2014-01-01

    Consistency relations — which relate an N-point function to a squeezed (N+1)-point function — are useful in large scale structure (LSS) because of their non-perturbative nature: they hold even if the N-point function is deep in the nonlinear regime, and even if they involve astrophysically messy galaxy observables. The non-perturbative nature of the consistency relations is guaranteed by the fact that they are symmetry statements, in which the velocity plays the role of the soft pion. In this paper, we address two issues: (1) how to derive the relations systematically using the residual coordinate freedom in the Newtonian gauge, and relate them to known results in ζ-gauge (often used in studies of inflation); (2) under what conditions the consistency relations are violated. In the non-relativistic limit, our derivation reproduces the Newtonian consistency relation discovered by Kehagias and Riotto and Peloso and Pietroni. More generally, there is an infinite set of consistency relations, as is known in ζ-gauge. There is a one-to-one correspondence between symmetries in the two gauges; in particular, the Newtonian consistency relation follows from the dilation and special conformal symmetries in ζ-gauge. We probe the robustness of the consistency relations by studying models of galaxy dynamics and biasing. We give a systematic list of conditions under which the consistency relations are violated; violations occur if the galaxy bias is non-local in an infrared divergent way. We emphasize the relevance of the adiabatic mode condition, as distinct from symmetry considerations. As a by-product of our investigation, we discuss a simple fluid Lagrangian for LSS

  3. Total and differential cross sections for pion production via coherent isobar and giant resonance formation in heavy-ion collisions

    International Nuclear Information System (INIS)

    Deutchman, P.A.; Norbury, J.W.; Townsend, L.W.

    1985-01-01

    A quantal many-body formalism is presented that investigates pion production through the coherent formation of a nucleonic isobar in the projectile and its subsequent decay to various pion charge states along with concomitant excitation of the target to a coherent spin-isospin giant resonance via a peripheral collision of relativistic heavy ions. Total cross sections as a function of the incident energy per nucleon and Lorentz-invariant differential cross sections as a function of pion energy and angle are calculated. It is shown that the pion angular distributions, in coincidence with the target giant resonance excitations, might provide a well-defined signature for these coherent processes

  4. Monte Carlo simulation of a medical linear accelerator for generation of phase spaces

    International Nuclear Information System (INIS)

    Oliveira, Alex C.H.; Santana, Marcelo G.; Lima, Fernando R.A.; Vieira, Jose W.

    2013-01-01

    Radiotherapy uses various techniques and equipment for local treatment of cancer. The equipment most often used in radiotherapy to the patient irradiation are linear accelerators (Linacs) which produce beams of X-rays in the range 5-30 MeV. Among the many algorithms developed over recent years for evaluation of dose distributions in radiotherapy planning, the algorithms based on Monte Carlo methods have proven to be very promising in terms of accuracy by providing more realistic results. The MC methods allow simulating the transport of ionizing radiation in complex configurations, such as detectors, Linacs, phantoms, etc. The MC simulations for applications in radiotherapy are divided into two parts. In the first, the simulation of the production of the radiation beam by the Linac is performed and then the phase space is generated. The phase space contains information such as energy, position, direction, etc. og millions of particles (photos, electrons, positrons). In the second part the simulation of the transport of particles (sampled phase space) in certain configurations of irradiation field is performed to assess the dose distribution in the patient (or phantom). The objective of this work is to create a computational model of a 6 MeV Linac using the MC code Geant4 for generation of phase spaces. From the phase space, information was obtained to asses beam quality (photon and electron spectra and two-dimensional distribution of energy) and analyze the physical processes involved in producing the beam. (author)

  5. Dispersion relation for hadronic light-by-light scattering: two-pion contributions

    Energy Technology Data Exchange (ETDEWEB)

    Colangelo, Gilberto [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Hoferichter, Martin [Institute for Nuclear Theory, University of Washington, Seattle, WA 98195-1550 (United States); Kavli Institute for Theoretical Physics, University of California,Santa Barbara, CA 93106 (United States); Procura, Massimiliano [Theoretical Physics Department, CERN, Geneva (Switzerland); Stoffer, Peter [Helmholtz-Institut für Strahlen- und Kernphysik (Theory)and Bethe Center for Theoretical Physics, University of Bonn, 53115 Bonn (Germany); Department of Physics, University of California at San Diego, La Jolla, CA 92093 (United States)

    2017-04-27

    In this third paper of a series dedicated to a dispersive treatment of the hadronic light-by-light (HLbL) tensor, we derive a partial-wave formulation for two-pion intermediate states in the HLbL contribution to the anomalous magnetic moment of the muon (g−2){sub μ}, including a detailed discussion of the unitarity relation for arbitrary partial waves. We show that obtaining a final expression free from unphysical helicity partial waves is a subtle issue, which we thoroughly clarify. As a by-product, we obtain a set of sum rules that could be used to constrain future calculations of γ{sup ∗}γ{sup ∗}→ππ. We validate the formalism extensively using the pion-box contribution, defined by two-pion intermediate states with a pion-pole left-hand cut, and demonstrate how the full known result is reproduced when resumming the partial waves. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box, a{sub μ}{sup π-box}=−15.9(2)×10{sup −11}. As an application of the partial-wave formalism, we present a first calculation of ππ-rescattering effects in HLbL scattering, with γ{sup ∗}γ{sup ∗}→ππ helicity partial waves constructed dispersively using ππ phase shifts derived from the inverse-amplitude method. In this way, the isospin-0 part of our calculation can be interpreted as the contribution of the f{sub 0}(500) to HLbL scattering in (g−2){sub μ}. We argue that the contribution due to charged-pion rescattering implements corrections related to the corresponding pion polarizability and show that these are moderate. Our final result for the sum of pion-box contribution and its S-wave rescattering corrections reads a{sub μ}{sup π-box}+a{sub μ,J=0}{sup ππ,π-pole} {sup LHC}=−24(1)×10{sup −11}.

  6. CLEO and E791 data: a smoking gun for the pion distribution amplitude?

    Energy Technology Data Exchange (ETDEWEB)

    Bakulev, A.P.; Mikhailov, S.V.; Stefanis, N.G

    2004-01-01

    The CLEO experimental data on the {pi}{gamma} transition are analyzed to next-to-leading order accuracy in QCD perturbation theory using light-cone QCD sum rules. By processing these data along the lines proposed by Schmedding and Yakovlev, and recently revised by us, we obtain new constraints for the Gegenbauer coefficients a{sub 2} and a{sub 4}, as well as for the inverse moment {sub {pi}} of the pion distribution amplitude (DA). The former determine the pion DA at low momentum scale, the latter is crucial in calculating pion form factors. From the results of our analysis we conclude that the data confirm the end-point suppressed shape of the pion DA we previously obtained with QCD sum rules and nonlocal condensates, while the exclusion of both the asymptotic and the Chernyak-Zhitnitsky DAs is reinforced at the 3{sigma}- and 4{sigma}-level, respectively. The reliability of the main results of our updated CLEO data analysis is demonstrated. Our pion DA is checked against the di-jets data from the E791 experiment, providing credible evidence for our results far more broadly.

  7. CLEO and E791 Data A Smoking Gun for the Pion Distribution Amplitude?

    CERN Document Server

    Bakulev, A P; Stefanis, N G

    2003-01-01

    The CLEO experimental data on the \\pi\\gamma transition are analyzed to NLO in QCD perturbation theory using light-cone QCD sum rules. By processing the data along the lines proposed by Khodjamiryan, Schmedding and Yakovlev, and recently revised by us, we obtain new constraints for the Gegenbauer coefficients a_2 and a_4, as well as for the inverse moment \\langle{x^{-1}\\rangle of the pion distribution amplitude (DA). The former determine the pion DA at low momentum scale, the latter is crucial in calculating pion form factors. From the results of our analysis we conclude that the data confirm the shape of the pion DA we previously obtained with QCD sum rules and nonlocal condensates, while the exclusion of the asymptotic and the Chernyak-Zhitnitsky DA is reinforced. We also investigate the sensitivity of the calculated coefficients in this analysis to the twist-4 contribution and check out pion DA against the di-jets data of the E791 experiment, providing credible evidence for our results far more broadly. Thu...

  8. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    CERN Document Server

    Romain, J P; Dayma, G; Boustie, M; Resseguier, T D; Combis, P

    2002-01-01

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm sup - sup 2. The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence <1.4 J cm sup - sup 2 , the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface.

  9. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    Energy Technology Data Exchange (ETDEWEB)

    Romain, J P [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Bonneau, F [Departement de Physique Theorique et Appliquee CEA/DAM Ile de France, BP 12, 91680 Bruyeres le Chatel (France); Dayma, G [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Boustie, M [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Resseguier, T de [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Combis, P [Departement de Physique Theorique et Appliquee CEA/DAM Ile de France, BP 12, 91680 Bruyeres le Chatel (France)

    2002-11-11

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm{sup -2}. The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence <1.4 J cm{sup -2}, the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface.

  10. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    International Nuclear Information System (INIS)

    Romain, J P; Bonneau, F; Dayma, G; Boustie, M; Resseguier, T de; Combis, P

    2002-01-01

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm -2 . The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence -2 , the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface

  11. Simulation of medical irradiation and X-ray detector signals

    Energy Technology Data Exchange (ETDEWEB)

    Kreisler, Bjoern

    2010-02-08

    This thesis aims for an improved understanding of medical irradiation. Two major parts are investigated: the beam shaping components of a medical linear accelerator, i.e. the source of the radiation, and the signal generation inside semiconductor sensors, i.e. the detection of the radiation. The direct measurement of the spatial and spectral particle distribution in the irradiation beam is not possible with state of the art detectors due to the high particle flux. The development of new advanced detectors is the goal of the first part of this thesis. The focus is set on the signal generation inside the sensor volume of a semiconductor detector. Incoming particles interact with the sensor material and generate clouds of electron hole pairs. These pairs get separated by an applied bias voltage. The motion of the charge clouds is simulated with a finite element programme taking into account the drift and diffusion. Mirror charges are induced on the electrodes which move due to the motion of the charge cloud. The motion of the induced mirror charges leads to the signal that is detected. The transient calculation of the signals is based on Ramo's theorem. The efficient adjoint formulation of the induction solution is adjusted to doped materials, as for example the electric bias field and hence the motion of the charge cloud is changing with the doping level. The effect of the doping of the material on the signal shape is shown together with influences of different voltages and pixel geometries. Smaller pixels and higher bias voltages can lead to shorter signals which is preferable for high flux measurements. Possible count rate improvements are limited by electric break through, high dark current across the sensor layer and charge sharing. Another option to shorten the signals is the use of steering grid electrodes which modify the electric and the weighting field. This results in shorter signals and thus in a higher possible rate. The detailed Monte

  12. Simulation of medical irradiation and X-ray detector signals

    International Nuclear Information System (INIS)

    Kreisler, Bjoern

    2010-01-01

    This thesis aims for an improved understanding of medical irradiation. Two major parts are investigated: the beam shaping components of a medical linear accelerator, i.e. the source of the radiation, and the signal generation inside semiconductor sensors, i.e. the detection of the radiation. The direct measurement of the spatial and spectral particle distribution in the irradiation beam is not possible with state of the art detectors due to the high particle flux. The development of new advanced detectors is the goal of the first part of this thesis. The focus is set on the signal generation inside the sensor volume of a semiconductor detector. Incoming particles interact with the sensor material and generate clouds of electron hole pairs. These pairs get separated by an applied bias voltage. The motion of the charge clouds is simulated with a finite element programme taking into account the drift and diffusion. Mirror charges are induced on the electrodes which move due to the motion of the charge cloud. The motion of the induced mirror charges leads to the signal that is detected. The transient calculation of the signals is based on Ramo's theorem. The efficient adjoint formulation of the induction solution is adjusted to doped materials, as for example the electric bias field and hence the motion of the charge cloud is changing with the doping level. The effect of the doping of the material on the signal shape is shown together with influences of different voltages and pixel geometries. Smaller pixels and higher bias voltages can lead to shorter signals which is preferable for high flux measurements. Possible count rate improvements are limited by electric break through, high dark current across the sensor layer and charge sharing. Another option to shorten the signals is the use of steering grid electrodes which modify the electric and the weighting field. This results in shorter signals and thus in a higher possible rate. The detailed Monte-Carlo simulation of

  13. Heat Generation by Irradiated Complex Composite Nanostructures

    DEFF Research Database (Denmark)

    Ma, Haiyan; Tian, Pengfei; Pello, Josselin

    2014-01-01

    Heating of irradiated metallic e-beam generated nanostructures was quantified through direct measurements paralleled by novel model-based numerical calculations. By comparing discs, triangles, and stars we showed how particle shape and composition determines the heating. Importantly, our results...... revealed that substantial heat is generated in the titanium adhesive layer between gold and glass. Even when the Ti layer is as thin as 2 nm it absorbs as much as a 30 nm Au layer and hence should not be ignored....

  14. Intermediate-energy nuclear photoabsorption and the pion optical potential

    International Nuclear Information System (INIS)

    Christillin, P.

    1984-01-01

    Nuclear photoabsorption around the pion threshold is schematised as photoproduction of a pion which undergoes final-stae interaction with the nucleus, accounted for by the pion optical potential. It is shown that real pion photoproduction and exchange effects are naturally described by the same mechanism with a non-static pion. The complementarity of photoabsorption to pion physics and its usefulness in gaining new information about pion-nucleus dynamics are stressed. (author)

  15. The effect of utilising age and sex dependent factors for calculating detriment from medical irradiation

    International Nuclear Information System (INIS)

    Mettler, F.A.; Davis, M.; Moseley, R.D.; Kelsey, C.A.

    1986-01-01

    Proposals have been made for a quantity that can be used to estimate possible detriment from medical radiology better than the ICRP's collective effective dose equivalent. One such approach utilises age and sex dependent 'weighting' factors. The magnitude of the effect obtained by utilising such factors when applied to an actual population has not been previously assessed. When age and sex dependent weighting factors are applied to diagnostic medical radiology for all hospital examinations conducted in the United States in 1980, estimates of detriment are reduced by one-third. (author)

  16. Risks for cancer induction by pion radiation in the peak- and plateau region

    International Nuclear Information System (INIS)

    Cottier, H.; Fritz-Niggli, H.; Froehlich, E.; Heinzell, F.; Nichel, C.; Rao, K.

    In the foreground of an evaluation of the suitability of negative protons for cancer therapy there is, beside the analysis of pion effect on malignant cells, also the reaction of healthy tissue. The observation that neutrons at the lowest dose-rate can induce breast cancer and our own results after pion radiation in the peak-region necessitate a broadly planned, urgent investigation of these delayed damages. We will consider radiations at the plateau- and peak-region, the results of which should be of utmost interest for the comparison of neutron- and pion therapy. There are indications that the RBE of a high LET radiation is extremely large for the tumor induction. We will investigate especially the development of mammary cancers in variously aged mice with a low spontaneous tumor rate and C 3 H mice with a high cancer expectancy

  17. Practical Calculational Scheme Implementing the Wilsonian RG Results for Nuclear Effective Field Theory Including Pions

    International Nuclear Information System (INIS)

    Kubo, H.; Harada, K.; Sakaeda, T.; Yamamoto, Y.

    2013-01-01

    On the basis of the Wilsonian renormalization group (WRG) analysis of nuclear effective field theory (NEFT) including pions, we propose a practical calculational scheme in which the short-distance part of one-pion exchange (S-OPE) is removed and represented as contact terms. The long-distance part of one-pion exchange (L-OPE) is treated as perturbation. The use of dimensional regularization (DR) for diagrams consisting only of contact interactions considerably simplifies the calculation of scattering amplitude and the renormalization group equations. NLO results for nucleon-nucleon elastic scattering in the S-waves are obtained and compared with experiments. A brief comment on NNLO calculations is given. (author)

  18. Compact Neutron Generators for Medical Home Land Security and Planetary Exploration

    International Nuclear Information System (INIS)

    Reijonen, J.

    2005-01-01

    The Plasma and Ion Source Technology Group at Lawrence Berkeley National Laboratory has developed various types of advanced D-D (neutron energy 2.5 MeV), D-T (14 MeV) and T-T (0-9 MeV) neutron generators for wide range of applications. These applications include medical (Boron Neutron Capture Therapy), homeland security (Prompt Gamma Activation Analysis, Fast Neutron Activation Analysis and Pulsed Fast Neutron Transmission Spectroscopy) and planetary exploration with a sub-surface material characterization on Mars. These neutron generators utilize RF induction discharge to ionize the deuterium/tritium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. Four main neutron generator developments are discussed here: high neutron output co-axial neutron generator for BNCT applications, point neutron generator for security applications, compact and sub-compact axial neutron generator for elemental analysis applications. Current status of the neutron generator development with experimental data will be presented

  19. A facility for pion-induced nuclear reaction studies with HADES

    Energy Technology Data Exchange (ETDEWEB)

    Adamczewski-Musch, J.; Heinz, T.; Holzmann, R.; Koenig, I.; Koenig, W.; Kolb, B.W.; Pechenov, V.; Pietraszko, J.; Schmidt, C.J.; Schwab, E.; Sturm, C.; Traxler, M.; Wendisch, C.; Zumbruch, P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Arnold, O.; Berger-Chen, J.C.; Epple, E.; Fabbietti, L.; Lalik, R.; Lapidus, K.; Mihaylov, D.M.; Muenzer, R.; Wirth, J. [Excellence Cluster ' ' Origin and Structure of the Universe' ' , Garching (Germany); Technische Universitaet Muenchen, Physik Department E62, Garching (Germany); Behnke, C.; Blume, C.; Froehlich, I.; Kardan, B.; Lorenz, M.; Markert, J.; Michel, J.; Muentz, C.; Pechenova, O.; Scheib, T.; Schuldes, H.; Sellheim, P.; Stroebele, H.; Wiebusch, M.G. [Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt (Germany); Belounnas, A.; Hennino, T.; Ramstein, B.; Rosier, P. [Institut de Physique Nucleaire, CNRS-IN2P3, Univ. Paris-Sud, Universite Paris-Saclay, Orsay (France); Belyaev, A.; Chernenko, S.; Fateev, O.; Ierusalimov, A.; Kurilkin, A.; Kurilkin, P.; Ladygin, V.; Zanevsky, Y. [Joint Institute of Nuclear Research, Dubna (Russian Federation); Biernat, J.; Dybczak, A.; Korcyl, G.; Nowakowski, K.N.; Palka, M.; Przygoda, W.; Salabura, P.; Strzempek, P. [Jagiellonian University of Cracow, Smoluchowski Institute of Physics, Krakow (Poland); Blanco, A.; Bordalo, P.; Fonte, P.; Franco, C.; Lopes, L.; Mangiarotti, A.; Ramos, S.; Silva, L. [Fisica Experimental de Particulas, Laboratorio de Instrumentacao, Coimbra (Portugal); Boehmer, M.; Friese, J.; Gernhaeuser, R.; Kunz, T.; Maier, L.; Maurus, S.; Schmidt-Sommerfeld, K.; Siebenson, J. [Technische Universitaet Muenchen, Physik Department E62, Garching (Germany); Chlad, C.; Kugler, A.; Rodriguez-Ramos, P.; Sobolev, Yu.G.; Svoboda, O.; Tlusty, P.; Wagner, V. [Czech Academy of Sciences, Nuclear Physics Institute, Rez (Czech Republic); Deveaux, C.; Hoehne, C.; Mahmoud, T.; Metag, V. [Justus Liebig Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Dreyer, J.; Kaempfer, B.; Kotte, R.; Naumann, L. [Helmholtz-Zentrum Dresden-Rossendorf, Institut fuer Strahlenphysik, Dresden (Germany); Filip, P.; Hlavac, S. [Slovak Academy of Sciences, Institute of Physics, Bratislava (Slovakia); Galatyuk, T. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Technische Universitaet Darmstadt, Darmstadt (Germany); Garzon, J.A. [Univ. de Santiago de Compostela, LabCAF.F. Fisica, Santiago de Compostela (Spain); Golubeva, M.; Guber, F.; Ivashkin, A.; Karavicheva, T.; Kurepin, A.; Morozov, S.; Petukhov, O.; Reshetin, A.; Sadovsky, A.; Usenko, E. [Russian Academy of Science, Institute for Nuclear Research, Moscow (Russian Federation); Gumberidze, M.; Kornakov, G.; Rost, A.; Seck, F. [Technische Universitaet Darmstadt, Darmstadt (Germany); Harabasz, S. [Jagiellonian University of Cracow, Smoluchowski Institute of Physics, Krakow (Poland); Technische Universitaet Darmstadt, Darmstadt (Germany); Lebedev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Scordo, A. [INFN, Laboratori Nazionali di Frascati, Roma (Italy); Scozzi, F. [Technische Universitaet Darmstadt, Darmstadt (Germany); Institut de Physique Nucleaire, CNRS-IN2P3, Univ. Paris-Sud, Universite Paris-Saclay, Orsay (France); Spataro, S. [Dipartimento di Fisica, Universita di Torino (Italy); INFN, Torino (Italy); Stroth, J. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt (Germany); Tsertos, H. [University of Cyprus, Department of Physics, Nicosia (Cyprus); Collaboration: HADES Collaboration

    2017-09-15

    The combination of a production target for secondary beams, an optimized ion optical beam line setting, in-beam detectors for minimum ionizing particles with high rate capability, and an efficient large acceptance spectrometer around the reaction target constitutes an experimental opportunity to study in detail hadronic interactions utilizing pion beams impinging on nucleons and nuclei. For the 0.4-2.0 GeV/c pion momentum regime such a facility is located at the heavy ion synchrotron accelerator SIS18 in Darmstadt (Germany). The layout of the apparatus, performance of its components and encouraging results from a first commissioning run are presented. (orig.)

  20. A facility for pion-induced nuclear reaction studies with HADES

    International Nuclear Information System (INIS)

    Adamczewski-Musch, J.; Heinz, T.; Holzmann, R.; Koenig, I.; Koenig, W.; Kolb, B.W.; Pechenov, V.; Pietraszko, J.; Schmidt, C.J.; Schwab, E.; Sturm, C.; Traxler, M.; Wendisch, C.; Zumbruch, P.; Arnold, O.; Berger-Chen, J.C.; Epple, E.; Fabbietti, L.; Lalik, R.; Lapidus, K.; Mihaylov, D.M.; Muenzer, R.; Wirth, J.; Behnke, C.; Blume, C.; Froehlich, I.; Kardan, B.; Lorenz, M.; Markert, J.; Michel, J.; Muentz, C.; Pechenova, O.; Scheib, T.; Schuldes, H.; Sellheim, P.; Stroebele, H.; Wiebusch, M.G.; Belounnas, A.; Hennino, T.; Ramstein, B.; Rosier, P.; Belyaev, A.; Chernenko, S.; Fateev, O.; Ierusalimov, A.; Kurilkin, A.; Kurilkin, P.; Ladygin, V.; Zanevsky, Y.; Biernat, J.; Dybczak, A.; Korcyl, G.; Nowakowski, K.N.; Palka, M.; Przygoda, W.; Salabura, P.; Strzempek, P.; Blanco, A.; Bordalo, P.; Fonte, P.; Franco, C.; Lopes, L.; Mangiarotti, A.; Ramos, S.; Silva, L.; Boehmer, M.; Friese, J.; Gernhaeuser, R.; Kunz, T.; Maier, L.; Maurus, S.; Schmidt-Sommerfeld, K.; Siebenson, J.; Chlad, C.; Kugler, A.; Rodriguez-Ramos, P.; Sobolev, Yu.G.; Svoboda, O.; Tlusty, P.; Wagner, V.; Deveaux, C.; Hoehne, C.; Mahmoud, T.; Metag, V.; Dreyer, J.; Kaempfer, B.; Kotte, R.; Naumann, L.; Filip, P.; Hlavac, S.; Galatyuk, T.; Garzon, J.A.; Golubeva, M.; Guber, F.; Ivashkin, A.; Karavicheva, T.; Kurepin, A.; Morozov, S.; Petukhov, O.; Reshetin, A.; Sadovsky, A.; Usenko, E.; Gumberidze, M.; Kornakov, G.; Rost, A.; Seck, F.; Harabasz, S.; Lebedev, A.; Scordo, A.; Scozzi, F.; Spataro, S.; Stroth, J.; Tsertos, H.

    2017-01-01

    The combination of a production target for secondary beams, an optimized ion optical beam line setting, in-beam detectors for minimum ionizing particles with high rate capability, and an efficient large acceptance spectrometer around the reaction target constitutes an experimental opportunity to study in detail hadronic interactions utilizing pion beams impinging on nucleons and nuclei. For the 0.4-2.0 GeV/c pion momentum regime such a facility is located at the heavy ion synchrotron accelerator SIS18 in Darmstadt (Germany). The layout of the apparatus, performance of its components and encouraging results from a first commissioning run are presented. (orig.)

  1. Employing UMLS for generating hints in a tutoring system for medical problem-based learning.

    Science.gov (United States)

    Kazi, Hameedullah; Haddawy, Peter; Suebnukarn, Siriwan

    2012-06-01

    While problem-based learning has become widely popular for imparting clinical reasoning skills, the dynamics of medical PBL require close attention to a small group of students, placing a burden on medical faculty, whose time is over taxed. Intelligent tutoring systems (ITSs) offer an attractive means to increase the amount of facilitated PBL training the students receive. But typical intelligent tutoring system architectures make use of a domain model that provides a limited set of approved solutions to problems presented to students. Student solutions that do not match the approved ones, but are otherwise partially correct, receive little acknowledgement as feedback, stifling broader reasoning. Allowing students to creatively explore the space of possible solutions is exactly one of the attractive features of PBL. This paper provides an alternative to the traditional ITS architecture by using a hint generation strategy that leverages a domain ontology to provide effective feedback. The concept hierarchy and co-occurrence between concepts in the domain ontology are drawn upon to ascertain partial correctness of a solution and guide student reasoning towards a correct solution. We describe the strategy incorporated in METEOR, a tutoring system for medical PBL, wherein the widely available UMLS is deployed and represented as the domain ontology. Evaluation of expert agreement with system generated hints on a 5-point likert scale resulted in an average score of 4.44 (Spearman's ρ=0.80, p<0.01). Hints containing partial correctness feedback scored significantly higher than those without it (Mann Whitney, p<0.001). Hints produced by a human expert received an average score of 4.2 (Spearman's ρ=0.80, p<0.01). Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Search for a neutral particle of mass 33.9 MeV in pion decay

    Energy Technology Data Exchange (ETDEWEB)

    Daum, M [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    We have measured the muon momentum distribution in charged pion decay in flight in order to search for a small branching fraction {eta} of pion decays {pi}{sup +}{yields}{mu}{sup +} 1 X, in which a heavy neutral particle X with a mass of 33.9 MeV would be emitted. Such a particle was postulated by the KARMEN collaboration as a possible explanation for an anomaly in their time-of-flight spectrum. In a first experiment we found an upper limit of {eta}{<=}2.6.10{sup -8} at a confidence level of 95%. (author) 4 figs., 9 refs.

  3. Bremsstrahlung γ-ray generation by electrons from gas jets irradiated by laser pulses for radiographic testing

    International Nuclear Information System (INIS)

    Oishi, Yuji; Nayuki, Takuya; Zhidkov, Alexei; Fujii, Takashi; Nemoto, Koshichi

    2012-01-01

    Electron generation from a gas jet irradiated by low energy femtosecond laser pulses is studied experimentally as a promising source of radiation for radioisotope-free γ-ray imaging systems. The calculated yield of γ-rays in the 0.5-2 MeV range, produced by low-average-power lasers and gas targets, exceeds the yields from solid tape targets up to 60 times. In addition, an effect of quasi-mono energetic electrons on γ-ray imaging is also discussed.

  4. On the role of secondary pions in spallation targets

    Energy Technology Data Exchange (ETDEWEB)

    Mancusi, Davide [Paris-Saclay Univ., Gif-sur-Yvette (France). Den-Service d' Etude des Reacteurs et de Mathematiques Appliquees (SERMA); Lo Meo, Sergio [ENEA, Research Centre ' ' Ezio Clementel' ' , Bologna (Italy); INFN, Bologna (Italy); Colonna, Nicola [INFN, Bari (Italy); Boudard, Alain; David, Jean-Christophe; Leray, Sylvie [Paris-Saclay Univ., Gif-sur-Yvette (France). IRFU, CEA; Cortes-Giraldo, Miguel Antonio; Lerendegui-Marco, Jorge [Sevilla Univ. (Spain). Facultad de Fisica; Cugnon, Joseph [Liege Univ. (Belgium). AGO Dept.; Massimi, Cristian [INFN, Bologna (Italy); Bologna Univ. (Italy). Physics and Astronomy Dept.; Vlachoudis, Vasilis [European Organization for Nuclear Research (CERN), Geneva (Switzerland)

    2017-05-15

    We use particle-transport simulations to show that secondary pions play a crucial role for the development of the hadronic cascade and therefore for the production of neutrons and photons from thick spallation targets. In particular, for the nTOF lead spallation target, irradiated with 20 GeV/c protons, neutral pions are involved in the production of ∝ 90% of the high-energy photons; charged pions participate in ∝ 40% of the integral neutron yield. Nevertheless, photon and neutron yields are shown to be relatively insensitive to large changes of the average pion multiplicity in the individual spallation reactions. We characterize this robustness as a peculiar property of hadronic cascades in thick targets. (orig.)

  5. On the role of secondary pions in spallation targets

    CERN Document Server

    Mancusi, Davide; Colonna, Nicola; Boudard, Alain; Cortés-Giraldo, Miguel Antonio; Cugnon, Joseph; David, Jean-Christophe; Leray, Sylvie; Lerendegui-Marco, Jorge; Massimi, Cristian; Vlachoudis, Vasilis

    2017-01-01

    We use particle-transport simulations to show that secondary pions play a crucial role for the development of the hadronic cascade and therefore for the production of neutrons and photons from thick spallation targets. In particular, for the n_TOF lead spallation target, irradiated with 20-GeV/c protons, neutral pions are involved in the production of ~90% of the high-energy photons; charged pions participate in ~40% of the integral neutron yield. Nevertheless, photon and neutron yields are shown to be relatively insensitive to large changes of the average pion multiplicity in the individual spallation reactions. We characterize this robustness as a peculiar property of hadronic cascades in thick targets.

  6. New algorithms for identifying the flavour of [Formula: see text] mesons using pions and protons.

    Science.gov (United States)

    Aaij, R; Adeva, B; Adinolfi, M; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Andreassi, G; Andreotti, M; Andrews, J E; Appleby, R B; Archilli, F; d'Argent, P; Arnau Romeu, J; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Babuschkin, I; Bachmann, S; Back, J J; Badalov, A; Baesso, C; Baker, S; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Baszczyk, M; Batozskaya, V; Batsukh, B; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Bel, L J; Bellee, V; Belloli, N; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bertolin, A; Betti, F; Bettler, M-O; van Beuzekom, M; Bezshyiko, Ia; Bifani, S; Billoir, P; Bird, T; Birnkraut, A; Bitadze, A; Bizzeti, A; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Boettcher, T; Bondar, A; Bondar, N; Bonivento, W; Bordyuzhin, I; Borgheresi, A; Borghi, S; Borisyak, M; Borsato, M; Bossu, F; Boubdir, M; Bowcock, T J V; Bowen, E; Bozzi, C; Braun, S; Britsch, M; Britton, T; Brodzicka, J; Buchanan, E; Burr, C; Bursche, A; Buytaert, J; Cadeddu, S; Calabrese, R; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Campora Perez, D H; Capriotti, L; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carniti, P; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cavallero, G; Cenci, R; Charles, M; Charpentier, Ph; Chatzikonstantinidis, G; Chefdeville, M; Chen, S; Cheung, S F; Chobanova, V; Chrzaszcz, M; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coco, V; Cogan, J; Cogneras, E; Cogoni, V; Cojocariu, L; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombs, G; Coquereau, S; Corti, G; Corvo, M; Costa Sobral, C M; Couturier, B; Cowan, G A; Craik, D C; Crocombe, A; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Da Cunha Marinho, F; Dall'Occo, E; Dalseno, J; David, P N Y; Davis, A; De Aguiar Francisco, O; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Serio, M; De Simone, P; Dean, C T; Decamp, D; Deckenhoff, M; Del Buono, L; Demmer, M; Dendek, A; Derkach, D; Deschamps, O; Dettori, F; Dey, B; Di Canto, A; Dijkstra, H; Dordei, F; Dorigo, M; Dosil Suárez, A; Dovbnya, A; Dreimanis, K; Dufour, L; Dujany, G; Dungs, K; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Déléage, N; Easo, S; Ebert, M; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; Elsasser, Ch; Ely, S; Esen, S; Evans, H M; Evans, T; Falabella, A; Farley, N; Farry, S; Fay, R; Fazzini, D; Ferguson, D; Fernandez Prieto, A; Ferrari, F; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fini, R A; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fleuret, F; Fohl, K; Fontana, M; Fontanelli, F; Forshaw, D C; Forty, R; Franco Lima, V; Frank, M; Frei, C; Fu, J; Furfaro, E; Färber, C; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; Garcia Martin, L M; García Pardiñas, J; Garra Tico, J; Garrido, L; Garsed, P J; Gascon, D; Gaspar, C; Gavardi, L; Gazzoni, G; Gerick, D; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianì, S; Gibson, V; Girard, O G; Giubega, L; Gizdov, K; Gligorov, V V; Golubkov, D; Golutvin, A; Gomes, A; Gorelov, I V; Gotti, C; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graverini, E; Graziani, G; Grecu, A; Griffith, P; Grillo, L; Gruberg Cazon, B R; Grünberg, O; Gushchin, E; Guz, Yu; Gys, T; Göbel, C; Hadavizadeh, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Han, X; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hatch, M; He, J; Head, T; Heister, A; Hennessy, K; Henrard, P; Henry, L; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hombach, C; Hopchev, P H; Hulsbergen, W; Humair, T; Hushchyn, M; Hussain, N; Hutchcroft, D; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jalocha, J; Jans, E; Jawahery, A; Jiang, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kandybei, S; Kanso, W; Karacson, M; Kariuki, J M; Karodia, S; Kecke, M; Kelsey, M; Kenyon, I R; Kenzie, M; Ketel, T; Khairullin, E; Khanji, B; Khurewathanakul, C; Kirn, T; Klaver, S; Klimaszewski, K; Koliiev, S; Kolpin, M; Komarov, I; Koopman, R F; Koppenburg, P; Kosmyntseva, A; Kozeiha, M; Kravchuk, L; Kreplin, K; Kreps, M; Krokovny, P; Kruse, F; Krzemien, W; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kuonen, A K; Kurek, K; Kvaratskheliya, T; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Leflat, A; Lefrançois, J; Lefèvre, R; Lemaitre, F; Lemos Cid, E; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Likhomanenko, T; Lindner, R; Linn, C; Lionetto, F; Liu, B; Liu, X; Loh, D; Longstaff, I; Lopes, J H; Lucchesi, D; Lucio Martinez, M; Luo, H; Lupato, A; Luppi, E; Lupton, O; Lusiani, A; Lyu, X; Machefert, F; Maciuc, F; Maev, O; Maguire, K; Malde, S; Malinin, A; Maltsev, T; Manca, G; Mancinelli, G; Manning, P; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marino, P; Marks, J; Martellotti, G; Martin, M; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massacrier, L M; Massafferri, A; Matev, R; Mathad, A; Mathe, Z; Matteuzzi, C; Mauri, A; Maurin, B; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Melnychuk, D; Merk, M; Merli, A; Michielin, E; Milanes, D A; Minard, M-N; Mitzel, D S; Mogini, A; Molina Rodriguez, J; Monroy, I A; Monteil, S; Morandin, M; Morawski, P; Mordà, A; Morello, M J; Moron, J; Morris, A B; Mountain, R; Muheim, F; Mulder, M; Mussini, M; Müller, D; Müller, J; Müller, K; Müller, V; Naik, P; Nakada, T; Nandakumar, R; Nandi, A; Nasteva, I; Needham, M; Neri, N; Neubert, S; Neufeld, N; Neuner, M; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nieswand, S; Niet, R; Nikitin, N; Nikodem, T; Novoselov, A; O'Hanlon, D P; Oblakowska-Mucha, A; Obraztsov, V; Ogilvy, S; Oldeman, R; Onderwater, C J G; Otalora Goicochea, J M; Otto, A; Owen, P; Oyanguren, A; Pais, P R; Palano, A; Palombo, F; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Pappalardo, L L; Parker, W; Parkes, C; Passaleva, G; Pastore, A; Patel, G D; Patel, M; Patrignani, C; Pearce, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perret, P; Pescatore, L; Petridis, K; Petrolini, A; Petrov, A; Petruzzo, M; Picatoste Olloqui, E; Pietrzyk, B; Pikies, M; Pinci, D; Pistone, A; Piucci, A; Playfer, S; Plo Casasus, M; Poikela, T; Polci, F; Poluektov, A; Polyakov, I; Polycarpo, E; Pomery, G J; Popov, A; Popov, D; Popovici, B; Poslavskii, S; Potterat, C; Price, E; Price, J D; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Quagliani, R; Rachwal, B; Rademacker, J H; Rama, M; Ramos Pernas, M; Rangel, M S; Raniuk, I; Ratnikov, F; Raven, G; Redi, F; Reichert, S; Dos Reis, A C; Remon Alepuz, C; Renaudin, V; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Robbe, P; Rodrigues, A B; Rodrigues, E; Rodriguez Lopez, J A; Rodriguez Perez, P; Rogozhnikov, A; Roiser, S; Rollings, A; Romanovskiy, V; Romero Vidal, A; Ronayne, J W; Rotondo, M; Rudolph, M S; Ruf, T; Ruiz Valls, P; Saborido Silva, J J; Sadykhov, E; Sagidova, N; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santimaria, M; Santovetti, E; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrina, D; Schael, S; Schellenberg, M; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmelzer, T; Schmidt, B; Schneider, O; Schopper, A; Schubert, K; Schubiger, M; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Semennikov, A; Sergi, A; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Shires, A; Siddi, B G; Silva Coutinho, R; Silva de Oliveira, L; Simi, G; Simone, S; Sirendi, M; Skidmore, N; Skwarnicki, T; Smith, E; Smith, I T; Smith, J; Smith, M; Snoek, H; Sokoloff, M D; Soler, F J P; Souza De Paula, B; Spaan, B; Spradlin, P; Sridharan, S; Stagni, F; Stahl, M; Stahl, S; Stefko, P; Stefkova, S; Steinkamp, O; Stemmle, S; Stenyakin, O; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Stracka, S; Straticiuc, M; Straumann, U; Sun, L; Sutcliffe, W; Swientek, K; Syropoulos, V; Szczekowski, M; Szumlak, T; T'Jampens, S; Tayduganov, A; Tekampe, T; Teklishyn, M; Tellarini, G; Teubert, F; Thomas, E; van Tilburg, J; Tilley, M J; Tisserand, V; Tobin, M; Tolk, S; Tomassetti, L; Tonelli, D; Topp-Joergensen, S; Toriello, F; Tournefier, E; Tourneur, S; Trabelsi, K; Traill, M; Tran, M T; Tresch, M; Trisovic, A; Tsaregorodtsev, A; Tsopelas, P; Tully, A; Tuning, N; Ukleja, A; Ustyuzhanin, A; Uwer, U; Vacca, C; Vagnoni, V; Valassi, A; Valat, S; Valenti, G; Vallier, A; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; van Veghel, M; Velthuis, J J; Veltri, M; Veneziano, G; Venkateswaran, A; Vernet, M; Vesterinen, M; Viaud, B; Vieira, D; Vieites Diaz, M; Vilasis-Cardona, X; Volkov, V; Vollhardt, A; Voneki, B; Vorobyev, A; Vorobyev, V; Voß, C; de Vries, J A; Vázquez Sierra, C; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wang, J; Ward, D R; Wark, H M; Watson, N K; Websdale, D; Weiden, A; Whitehead, M; Wicht, J; Wilkinson, G; Wilkinson, M; Williams, M; Williams, M P; Williams, M; Williams, T; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wraight, K; Wyllie, K; Xie, Y; Xu, Z; Yang, Z; Yin, H; Yu, J; Yuan, X; Yushchenko, O; Zarebski, K A; Zavertyaev, M; Zhang, L; Zhang, Y; Zhelezov, A; Zheng, Y; Zhokhov, A; Zhu, X; Zhukov, V; Zucchelli, S

    2017-01-01

    Two new algorithms for use in the analysis of [Formula: see text] collision are developed to identify the flavour of [Formula: see text] mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using [Formula: see text] decays from [Formula: see text] collision data collected by LHCb at centre-of-mass energies of 7 and 8 TeV . The tagging power of the new pion algorithm is 60% greater than the previously available one; the algorithm using protons to identify the flavour of a [Formula: see text] meson is the first of its kind.

  7. A Ranking Method for Neutral Pion and Eta Selection in Hadronic Events

    International Nuclear Information System (INIS)

    Bingoel, A.

    2004-01-01

    The selection of neutral pions and etas with a high purity while maintaining also a high efficiency can be important in the formation of statistically significant mass spectra in the reconstruction of short-lived particles such as the omega meson (ω→π + + π - + π 0 ). In this study a Ranking method has been optimized for data from the ALEPH Experiment, CERN. The results show that the Ranking method, when applied to high multiplicity events, yields significant improvements in the purity of selected pion candidates and facilitates the relaxation of standard cuts thereby avoiding some systematic uncertainties

  8. Pion radiation therapy

    International Nuclear Information System (INIS)

    Kligerman, M.M.

    1975-01-01

    Results are summarized from studies on the relative biological effects as compared with x or γ radiation and OER of negative pi mesons produced by the Berkeley 184-inch synchrocyclotron or the NIMROD 7-GeV proton synchrocyclotron at the Rutherford High Energy Laboratory in England using cultured animal cells or Vicia faba cells as the test system. Preliminary results are reported from similar radiobiological studies at the Los Alamos Meson Physics Facility. The relative response of human tissues to peak pion irradiation was compared with 140 kV x rays in a single patient with multiple malignant melanoma by observing the acute response of the skin surrounding metastatic modules following exposure to either pions or x radiation. Color photographs of the irradiated areas made at least twice weekly and densitometry measurements and observations by radiation therapists indicated that maximum erythemia occurred during the fifth, sixth, or seventh week after the start of a schedule of fractionated exposure to 15 fractions over 19 elapsed days. X irradiation was delivered at a dose rate of 500 rads/min to modules to deliver 55, 66, or 75 percent of a skin surface dose of 5,200 rads and pion irradiation, at doses numerically 50 percent of the x ray dose, was delivered at a dose rate of 5 to 7 rads/min. Dose response curves were plotted. Results of histological examinations of skin samples taken 24 weeks following irradiation are reported. Results are discussed relative to the destruction of melanoma cells following pion or x ray treatment

  9. Pion production in nuclei

    International Nuclear Information System (INIS)

    Afnan, I.R.; Thomas, A.W.

    1976-01-01

    A method has been suggested for relating μ-capture in nuclei to pion absorption through partially conserved axial vector current hypothesis. The success of the method relies heavily on the knowledge of the pion absorption amplitude at a momentum transfer equal to the μ-meson mass. That is we need to know the pion absorption amplitude off the mass-shell. The simplest nucleus for which this suggestion can be examined is μ-capture in deuterium. The Koltum-Reitan model is used to determine the pion absorption amplitude off the mass shell. In particular the senstivity of this off-mass-shell extrapolution to details of the N-N interaction is studied. (author)

  10. Somatic embryogenesis and embryo culture coupled with gamma irradiation for generating avocado (Persea americana Miller) mutants in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Avenido, R. A. [Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños (Philippines); Crop Science Cluster, College of Agriculture, University of the Philippines Los Baños (Philippines); Galvez, H. F.; Dimaculangan, J. G.; Welgas, J. N.; Frankie, R. B.; Damasco, O. P. [Crop Science Cluster, College of Agriculture, University of the Philippines Los Baños (Philippines)

    2009-05-15

    -derived regenerants from non-irradiated embryogenic cultures. Mass screening for mutations will be done on all successfully potted out regenerants. A second protocol involving embryo culture and gamma irradiation was also done. Mature embryos of 9 genotypes were cultured using liquid MS basal medium with 30 g/l sucrose and 2 mg/l BAP, with 100% germination. Germinating zygotic embryos of ‘San Felix’ were also gamma irradiated and the LD{sub 50} between 20 to 30 Gy was established. M{sub 1}V{sub 4} shoots were generated from gamma-irradiated seedlings after subsequent micropropagation cycles. This is the first successful application of tissue culture and gamma irradiation technologies towards the improvement of a woody perennial fruit crop in the Philippines. (author)

  11. ImageParser: a tool for finite element generation from three-dimensional medical images

    Directory of Open Access Journals (Sweden)

    Yamada T

    2004-10-01

    Full Text Available Abstract Background The finite element method (FEM is a powerful mathematical tool to simulate and visualize the mechanical deformation of tissues and organs during medical examinations or interventions. It is yet a challenge to build up an FEM mesh directly from a volumetric image partially because the regions (or structures of interest (ROIs may be irregular and fuzzy. Methods A software package, ImageParser, is developed to generate an FEM mesh from 3-D tomographic medical images. This software uses a semi-automatic method to detect ROIs from the context of image including neighboring tissues and organs, completes segmentation of different tissues, and meshes the organ into elements. Results The ImageParser is shown to build up an FEM model for simulating the mechanical responses of the breast based on 3-D CT images. The breast is compressed by two plate paddles under an overall displacement as large as 20% of the initial distance between the paddles. The strain and tangential Young's modulus distributions are specified for the biomechanical analysis of breast tissues. Conclusion The ImageParser can successfully exact the geometry of ROIs from a complex medical image and generate the FEM mesh with customer-defined segmentation information.

  12. Choice of the irradiation dose for the sterilization of medical products

    International Nuclear Information System (INIS)

    Bochkarev, V.V.; Pavlov, E.P.; Sedov, V.V.; Khrushchev, V.G.; Tushov, Eh.G.; Konyaev, G.A.

    1975-01-01

    The principles for selecting the appropriate dose for the radiation sterilization of medical products are set forth, taking into account the initial contamination of the product, the radiation senstivity of contaminants and the required level of reliability of sterilization. The initial contamination level of certain preparations (glucose and radiopharmaceuticals) is established and the radiation sensitivity of the isolated contaminants is determined in terms of Dio indices. Of the microorganisms isolated the most common were staphylococci, streptococci, Gram-negative bacteria, Aspergilli, Penicillia and yeast fungi. Spore-forming types of microorganisms were isolated with a frequency of the order of 10 -2 . The radiation sensitivity in terms of D 10 was established for more than 3000 strains of microorganisms. For 75-85% of the strains the D 10 indices gave 10-40 krad and for 0.2-1% more than 100 krad. The experimental data were subjected to computer analysis which confirmed the adequacy of the techniques used to determine radiosensitivity. The authors then calculated by computer the radiation sterilizing doses for different degrees of initial contamination of the products with reliability coefficients of 10 6 and 10 8 . For sterilizing radiopharmaceuticals and glucose solutions these doses are 0.8-1 Mrad. Verification experiments show that these doses give reliable sterilization of the medical products concerned. (author)

  13. Doorway-resonance model for pion-nucleon D- and F-wave scattering

    International Nuclear Information System (INIS)

    Ernst, D.J.; Parnell, G.E.; Assad, C.; Texas A and M Univ., College Station, TX

    1990-01-01

    A model for the resonant pion-nucleon D- and F-waves is developed which assumes that the pion-plus-nucleon couples to a resonance and that the resonance can serve as a doorway to the inelastic channels. With the use of simple form factors, the model is capable of reproducing the pion-nucleon phase shifts up to an energy of T π =1.4 GeV if the coupling of the elastic channel to the inelastic channels is taken from data as input into the model. A value for the mass of the resonance that would result in the absence of the coupling to decay channels is extracted from the data utilizing the model. This is the mass that is most easily modeled by bag models. For the non-resonant D- and F-wave channels a separable potential model is used. This model, like the resonance model, is developed utilizing the invariant amplitude which is free of kinematic singularities and uses invariant norms and phase spaces. The model is also applied to the S-wave channels. A relation between the resonance model and the Chew-Low model is discovered and used to derive an extended Chew-Low model which is applied to the P 13 , P 31 and P 33 channels. Implications of the model for understanding the range of the pion-nucleon interaction and the dynamic structure of the interaction are presented. (orig.)

  14. New algorithms for identifying the flavour of B0 mesons using pions and protons

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Everse, LA; Anderlini, L.; Andreassi, G.; Andreotti, M.; Andrews, J.E.; Appleby, R. B.; Archilli, F.; d’Argent, P.; Arnau Romeu, J.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Babuschkin, I.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baker, S.C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Baszczyk, M.; Batozskaya, V.; Batsukh, B.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Betti, F.; Bettler, M-O.; Van Beuzekom, Martin; Bezshyiko, Ia; Bifani, S.; Billoir, P.; Bird, T.D.; Birnkraut, A.; Bitadze, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Boettcher, T.; Bondar, A.; Bondar, N.; Bonivento, W.; Bordyuzhin, I.; Borgheresi, A.; Borghi, S.; Borisyak, M.; Borsato, M.; Bossu, F.; Boubdir, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Buchanan, E.; Burr, C.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Campora Perez, D. H.; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph; Chatzikonstantinidis, G.; Chefdeville, M.; Chen, S.; Cheung, S-F.; Chobanova, V.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombs, G.; Coquereau, S.; Corti, G.; Corvo, M.; Costa Sobral, C. M.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, C.R.; D’Ambrosio, C.; Da Cunha Marinho, F.; Dall’Occo, E.; Dalseno, J.; David, P. N.Y.; Davis, A.; De Aguiar Francisco, O.; De Bruyn, K.; De Capua, S.; De Cian, M.; de Miranda, J. M.; Paula, L.E.; De Serio, M.; De Simone, P.; Dean, C-T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Demmer, M.; Dendek, A.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Dijkstra, H.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dungs, K.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Déléage, N.; Easo, S.; Ebert, M.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T. M.; Falabella, A.; Farley, N.; Farry, S.; Fay, R.; Fazzini, D.; Ferguson, D.; Fernandez Prieto, A.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fini, R. A.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fleuret, F.; Fohl, K.; Fontana, Mark; Fontanelli, F.; Forshaw, D. C.; Forty, R.; Franco Lima, V.; Frank, M.; Frei, C.; Fu, J.; Furfaro, E.; Färber, C.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Garcia Martin, L. M.; García Pardiñas, J.; Garra Tico, J.; Garrido, L.; Garsed, P. J.; Gascon, D.; Carvalho-Gaspar, M.; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T. J.; Ghez, Ph; Gianì, S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gizdov, K.; Gligorov, V. V.; Golubkov, D.; Golutvin, A.; Gomes, A.Q.; Gorelov, I. V.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graverini, E.; Graziani, G.; Grecu, A.; Griffith, P.; Grillo, L.; Gruberg Cazon, B. R.; Grünberg, O.; Gushchin, E.; Guz, Yu; Gys, T.; Göbel, C.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hatch, M.J.; He, J.; Head, T.; Heister, A.J.G.A.M.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hombach, C.; Hopchev, P. H.; Hulsbergen, W.; Humair, T.; Hushchyn, M.; Hussain, N.; Hutchcroft, D. E.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jiang, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Kariuki, J. M.; Karodia, S.; Kecke, M.; Kelsey, M. H.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khairullin, E.; Khanji, B.; Khurewathanakul, C.; Kirn, T.; Klaver, S.M.; Klimaszewski, K.; Koliiev, S.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Kosmyntseva, A.; Kozeiha, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krokovny, P.; Kruse, F.; Krzemien, W.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kuonen, A. K.; Kurek, K.; Kvaratskheliya, T.; Lacarrere, D.; Lafferty, G. D.; Lai, A.; Lambert, D.M.; Lanfranchi, G.; Langenbruch, C.; Latham, T. E.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J. P.; Leflat, A.; Lefrançois, J.; Lefèvre, R.; Lemaitre, F.; Lemos Cid, E.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Likhomanenko, T.; Lindner, R.; Linn, S.C.; Lionetto, F.; Liu, B.; Liu, X.; Loh, D.; Longstaff, I.; Lopes, J. H.; Lucchesi, D.; Lucio Martinez, M.; Luo, H.; Lupato, A.; Luppi, E.; Lupton, O.; Lusiani, A.; Lyu, X.; Machefert, F.; Maciuc, F.; Maev, O.; Maguire, K.; Malde, S.; Malinin, A.; Maltsev, T.; Manca, G.; Mancinelli, G.; Manning, P.; Maratas, J.; Marchand, J. F.; Marconi, U.; Marin Benito, C.; Marino, P.; Marks, J.; Martellotti, G.; Martin, M.; Martinelli-Boneschi, F.; Martinez-Santos, D.; Martinez-Vidal, F.; Martins Tostes, D.; Massacrier, L. M.; Massafferri, A.; Matev, R.; Mathad, A.; Mathe, Z.; Matteuzzi, C.; Mauri, A.; Maurin, B.; Mazurov, A.; McCann, M.; McCarthy, J.; Mcnab, A.; McNulty, R.; Meadows, B. T.; Meier, F.; Meissner, M.; Melnychuk, D.; Merk, M.; Merli, A.; Michielin, E.; Milanes, D. A.; Minard, M. N.; Mitzel, D. S.; Mogini, A.; Molina Rodriguez, J.; Monroy, I. A.; Monteil, S.; Morandin, M.; Morawski, P.; Mordà, A.; Morello, M. J.; Moron, J.; Morris, A. B.; Mountain, R.; Muheim, F.; Mulder, M.; Mussini, M.; Müller, D.; Müller, J.; Müller, Karl; von Müller, L.; Naik, P.; Nakada, T.; Nandakumar, R.; Nandi, A.; Nasteva, I.; Needham, M.; Neri, N.; Neubert, S.; Neufeld, N.; Neuner, M.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nieswand, S.; Niet, R.; Nikitin, N.; Nikodem, T.; Novoselov, A.; O’Hanlon, D. P.; Oblakowska-Mucha, A.; Obraztsov, V.; Ogilvy, S.; Oldeman, R.; Onderwater, C. J.G.; Otalora Goicochea, J. M.; Otto, E.A.; Owen, R.P.; Oyanguren, A.; Pais, P. R.; Palano, A.; Palombo, F.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Pappalardo, L.L.; Parker, W.S; Parkes, C.; Passaleva, G.; Pastore, A.; Patel, G. D.; Patel, M.; Patrignani, C.; Pearce, D.A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perret, P.; Pescatore, L.; Petridis, K.; Petrolini, A.; Petrov, A.; Petruzzo, M.; Picatoste Olloqui, E.; Pietrzyk, B.; Pikies, M.; Pinci, D.; Pistone, A.; Piucci, A.; Playfer, S.; Plo Casasus, M.; Poikela, T.; Polci, F.; Poluektov, A.; Polyakov, I.; Polycarpo, E.; Pomery, G. J.; Popov, A.; Popov, D.; Popovici, B.; Poslavskii, S.; Potterat, C.; Price, M. E.; Price, J.D.; Prisciandaro, J.; Pritchard, C.A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, Y.W.; Quagliani, R.; Rachwal, B.; Rademacker, J. H.; Rama, M.; Ramos Pernas, M.; Rangel, M. S.; Raniuk, I.; Ratnikov, F.; Raven, G.; Redi, F.; Reichert, S.; dos Reis, A. C.; Remon Alepuz, C.; Renaudin, V.; Ricciardi, S.; Richards, Jennifer S; Rihl, M.; Rinnert, K.; Rives Molina, V.; Robbe, P.; Rodrigues, A. B.; Rodrigues, L.E.T.; Rodriguez Lopez, J. A.; Rodriguez Perez, P.; Rogozhnikov, A.; Roiser, S.; Rollings, A.; Romanovskiy, V.; Romero Vidal, A.; Ronayne, J. W.; Rotondo, M.; Rudolph, M. S.; Ruf, T.; Ruiz Valls, P.; Saborido Silva, J. J.; Sadykhov, E.; Sagidova, N.; Saitta, B.; Salustino Guimaraes, V.; Sanchez Mayordomo, C.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santimaria, M.; Santovetti, E.; Sarti, A.; Satriano, C.; Satta, A.; Saunders, D. M.; Savrina, D.; Schael, S.; Schellenberg, M.; Schiller, M.; Schindler, R. H.; Schlupp, M.; Schmelling, M.; Schmelzer, T.; Schmidt, B.; Schneider, O.; Schopper, A.; Schubert, K.; Schubiger, M.; Schune, M. H.; Schwemmer, R.; Sciascia, B.; Sciubba, A.; Semennikov, A.; Sergi, A; Serra, N.; Serrano, J.; Sestini, L.; Seyfert, P.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, V.; Shires, A.; Siddi, B. G.; Silva Coutinho, R.; Silva de Oliveira, L.; Simi, G.; Simone, S.; Sirendi, M.; Skidmore, N.; Skwarnicki, T.; Smith, E.; Smith, I. T.; Smith, J; Smith, M.; Snoek, H.; Sokoloff, M. D.; Soler, F. J. P.; Souza De Paula, B.; Spaan, B.; Spradlin, P.; Sridharan, S.; Stagni, F.; Stahl, M.; Stahl, S.; Stefko, P.; Stefkova, S.; Steinkamp, O.; Stemmle, S.; Stenyakin, O.; Stevenson-Moore, P.; Stoica, S.; Stone, S.; Storaci, B.; Stracka, S.; Straticiuc, M.; Straumann, U.; Sun, L.; Sutcliffe, W.; Swientek, K.; Syropoulos, V.; Szczekowski, M.; Szumlak, T.; T’Jampens, S.; Tayduganov, A.; Tekampe, T.; Teklishyn, M.; Tellarini, G.; Teubert, F.; Thomas, E.; van Tilburg, J.; Tilley, M. J.; Tisserand, V.; Tobin, M. N.; Tolk, S.; Tomassetti, L.; Tonelli, D.; Topp-Joergensen, S.; Toriello, F.; Tournefier, E.; Tourneur, S.; Trabelsi, K.; Traill, M.; Tran, N.T.M.T.; Tresch, M.; Trisovic, A.; Tsaregorodtsev, A.; Tsopelas, P.; Tully, M.A.; Tuning, N.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vacca, C.; Vagnoni, V.; Valassi, A.; Valat, S.; Valenti, G.; Vallier, A.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vecchi, S.; van Veghel-Plandsoen, M.M.; Velthuis, M.J.; Veltri, M.; Veneziano, G.; Venkateswaran, A.; Vernet, M.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vieites Diaz, M.; Vilasis-Cardona, X.; Volkov, V.; Vollhardt, A.; Voneki, B.; Vorobyev, A.; Vorobyev, V.; Voß, C.; de Vries, J. A.; Vázquez Sierra, C.; Waldi, R.; Wallace, C.; Wallace, R.; Walsh, John; Wang, J.; Ward, D. R.; Wark, H. M.; Watson, N. K.; Websdale, D.; Weiden, A.; Whitehead, M.; Wicht, J.; Wilkinson, G.; Wilkinson, M.; Williams, M.; Williams, M.P.; Williams, M.; Williams, T.; Wilson, James F; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wraight, K.; Wyllie, K.; Xie, Y.; Xu, Z.; Yang, Z.; Yin, H; Yu, J.; Yuan, X.; Yushchenko, O.; Zarebski, K. A.; Zavertyaev, M.; Zhang, L.; Zhang, Y.; Zhelezov, A.; Zheng, Y.; Zhokhov, A.; Zhu, X.; Zhukov, V.; Zucchelli, S.

    2017-01-01

    Two new algorithms for use in the analysis of pp collision are developed to identify the flavour of B0 mesons at production using pions and protons from the hadronization process. The algorithms are optimized and calibrated on data, using B0→D-π+ decays from pp collision data collected by LHCb at

  15. Current algebra method for form factors and strong decays with hard pions and kaons

    International Nuclear Information System (INIS)

    Srivastava, P.P.

    1969-01-01

    The F K /F Π ratio between the kaon and pion decay couplings in one lepton pair, sum rules for Weinberg spectral functions, form factor renormalization of the K l3 decay because of the SU(3) symmetry violation and the calculations of strong decays of the K* and K A strange resonances are presented and discussed. (L.C.) [pt

  16. Guidelines for industrial radiation sterilization of disposable medical products (Cobalt-60 gamma irradiation)

    International Nuclear Information System (INIS)

    1990-01-01

    This IAEA document is aimed at providing necessary guidance on standards and criteria and assistance to Member States, particularly developing countries, in their attempts to properly set up facilities for industrial radiation sterilization of duly-manufactured medical products by exposure to Co-60 gamma radiation. The contents of the guidelines have therefore been designed, as far as practicable, to reflect the practices and procedures currently employed in the processing of the majority of the radiation-sterilized medical products being produced worldwide. Consequently, this document has attempted to present to its users, for information and for action, all the relevant features of the standard criteria as are currently in existence under the auspices of the various authoritative national and/or regional Codes or Guides. The potential user(s) from Member States are expected to freely decide which of the various standards as enumerated in the Guidelines document should be considered for inclusion or exclusion either partially or totally in the context of the formulation of their own nationally-acceptable guidelines. Refs and tabs

  17. Organizational procedure for the study of pion production and absorption processes on nuclei

    International Nuclear Information System (INIS)

    Banerjee, M.K.; Walker, G.E.

    1983-01-01

    For nuclear processes involving pions, such as pion production/absorption or exchange currents, it is shown that a natural organization involves adoption of the πNN vertex function g/sub π/(q 2 )#betta# 5 tau/sub α/, where q is the pion four-momentum and g/sub π/(m/sub π/ 2 )approx. =13.4 is the renormalized pion-nucleon coupling constant. The result is independent of the form and details of any fundamental interaction Lagrangian. The difference between g/sub π/(q 2 )#betta# 5 tau/sub α/ and the fully-dressed πNN vertex function contributes to amplitudes involving more bosons, e.g., scattering amplitudes (πN→πN), production amplitudes (πN→ππN), etc. Such contributions are mediated through either seagull-like terms or P11 intermediate states. It is pointed out that it is neither necessary nor practical to calculate these partial contributions to scattering and production amplitudes. One can always exploit other approaches, theoretical and phenomenological, to make reasonably good models for the full amplitudes. The usual procedure of including the effects of negative energy parts of the nucleon propagator in interaction potentials, exchange currents, etc., is easily included in the present organization. The result is that from scattering amplitudes, etc; the positive energy nucleon poles are deleted but Z graphs are included

  18. Low energy pion--nucleon and pion--deuteron interactions

    International Nuclear Information System (INIS)

    Burman, R.L.

    1975-01-01

    This survey concentrates upon current experiments in the fields of pion-nucleon and pion-deuteron interactions, for low-energy incident pions--below 300 MeV. The discussion is restricted to very recent work. The topics to be covered are: π +- p → π +- p, Elastic Scattering; π +- p → π +- pγ, Bremsstrahlung; π + d → pp, Absorption; π d → π + d, Elastic Scattering; and π + d → π + pn, Breakup. (14 figures) (U.S.)

  19. Pion polarizabilities measurement at COMPASS

    CERN Document Server

    Guskov, Alexey

    2008-01-01

    The electromagnetic structure of pions is probed in $\\pi^{−}+(A,Z) \\rightarrow\\pi^{−}+(A,Z)+\\gamma$ Compton scattering in inverse kinematics (Primakoff reaction) and described by the electric ($\\bar{\\alpha_{\\pi}}$) and the magnetic ($\\bar{\\beta_{\\pi}}$) polarizabilities that depend on the rigidity of pion’s internal structure as a composite particle. Values for pion polarizabilities can be extracted from the comparison of the differential cross section for scattering of pointlike pions with the measured cross section. The pion polarizability measurement was performed with a $\\pi^{-}$ beam of 190 GeV. The high beam intensity, the good spectrometer resolution, the high rate capability, the high acceptance and the possibility to use pion and muon beams, unique to the COMPASS experiment, provide the tools to measure precisely the pion polarizabilities in the Primakoff reaction.

  20. Data acquisition and command system for use with a microprocessor-based control chassis

    International Nuclear Information System (INIS)

    Halbig, J.K.; Klosterbuer, S.F.; Martinez, V.A. Jr.

    1980-01-01

    The Pion Generation for Medical Irradiations (PIGMI) program at the Los Alamos Scientific Laboratory is developing the technology to build smaller, less expensive, and more reliable proton linear accelerators for medical applications, and has designed a powerful, simple, inexpensive, and reliable control and data acquisition system that is central to the program development. The system is a NOVA-3D minicomputer interfaced to several outlying microprocessor-based controllers, which accomplish control and data acquisition through data I/O chasis. The equipment interface chassis, which can issue binary commands, read binary data, issue analog commands, and read timed and untimed analog data is described

  1. Recommendations of the publication ICRP-84: pregnancy and medical irradiation for radiotherapy

    International Nuclear Information System (INIS)

    Rojkind, Roberto H.

    2001-01-01

    The malignant diseases in the pregnant women are relatively not much frequent, and some of these cases can be applied radiotherapy for the tumours treatment. The doses involved in the radio therapeutics procedures can produce a significant foetal damage, and the patient or worker has the right to know the magnitude and the potential effects that can be results of the radiotherapy exposure. The publication ICRP-84 of the International Commission of Radiological Protection approaches specific aspect of the individual justification of the medical exposure of the patient pregnant woman, and recommends work procedures for the dose optimization that will receive the fetus. In this communication is commented the content of the radiotherapy section of the mentioned publication

  2. Pion-pair formation and the pion dispersion relation in a hot pion gas

    Energy Technology Data Exchange (ETDEWEB)

    Chanfay, G. [Lyon-1 Univ., 69 - Villeurbanne (France). Inst. de Physique Nucleaire; Alm, T. [Rostock Univ. (Germany); Schuck, P. [Grenoble-1 Univ., 38 (France). Inst. des Sciences Nucleaires; Welke, G. [Wayne State Univ., Detroit, MI (United States). Dept. of Physics and Astronomy

    1996-09-01

    The possibility of pion-pair formation in a hot pion gas, based on the bosonic gap equation, is pointed out and discussed in detail. The critical temperature for condensation of pion pairs (Evans-Rashind transition) is determined as a function of the pion density. As for fermions, this phase transition is signaled by the appearance of a pole in the two-particle propagator. In Bose systems there exists a second, lower critical temperature, associated with the appearance of the single-particle condensate. Between the two critical temperatures the pion dispersion relation changes from the usual quasiparticle dispersion to a Bogoliubov-like dispersion relation at low momenta. This generalizes the non-relativistic results for an attractive Bose gas by Evans et al. Possible consequences for the inclusive pion spectra measured in heavy-ion collisions at ultra-relativistic energies are discussed. 21 refs.

  3. Exclusive electroproduction of pion pairs

    International Nuclear Information System (INIS)

    Warkentin, N.; Schaefer, A.; Diehl, M.; Ivanov, D. Yu.

    2007-01-01

    We investigate electroproduction of pion pairs on the nucleon in the framework of QCD factorization for hard exclusive processes. We extend previous analyses by taking the hard-scattering coefficients at next-to-leading order in α s . The dynamics of the produced pion pair is described by two-pion distribution amplitudes, for which we perform a detailed theoretical and phenomenological analysis. In particular, we obtain constraints on these quantities by comparing our results with measurements of angular observables that are sensitive to the interference between two-pion production in the isoscalar and isovector channels. (orig.)

  4. Food processing with electrically generated photon irradiation

    International Nuclear Information System (INIS)

    Matthews, S.M.

    1983-01-01

    A conceptual design for a portable electric food irradiation processing machine is presented and analyzed for cost assuming the required accelerators are available for $1.5 million each. It is shown that food can be processed to 1 kGy for a price of $5.98/ton

  5. NF EN ISO 11137-1, July 2006. Sterilization of health care products - Irradiation - Part 1: Requirements for development, validation and routine control of a sterilization process for medical devices

    International Nuclear Information System (INIS)

    2006-01-01

    This part of the ISO 11137 standard specifies requirements for the development, validation and routine control of a radiation sterilization process for medical devices. Although the scope of this part of the ISO 11137 standard is limited to medical devices, it specifies requirements and provides guidance that may be applicable to other products and equipment. This part of the international standard covers radiation processes employing irradiators using the radionuclide 60 Co or 137 Cs, a beam from an electron generator or a beam from an X-ray generator. This part of the international standard does not: - specify requirements for development, validation and routine control of a process for inactivating the causative agents of spongiform encephalopathies such as scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease; - detail specified requirements for designating a medical device as sterile; - specify a quality management system for the control of all stages of production of medical devices; - specify requirements for occupational safety associated with the design and operation of irradiation facilities; - specify requirements for the sterilization of used or reprocessed devices

  6. Medical irradiation of children. Beware of too fast conclusion

    International Nuclear Information System (INIS)

    Brisse, H.; Sirinelli, D.; Adamsbaum, C.; Chateil, J.F.; Claudon, M.; Geoffray, A.; Petit, P.; Rausin, L.; Panuel, M.

    2004-01-01

    The publication in january 2004 in the British medical journal of the article of P. Hall and coll. 'Effect of low doses of ionizing irradiation in infancy on cognitive function in adulthood: Swedish population based cohort study, has been noticed by the Radiation protection group of the French speaking society of pediatrics imaging. The authors evaluate the psycho-motor development of less eighteen months years old children and irradiated between 1930 and 1959 for a face angioma. They study for each dose of irradiation ( from 0 to 250 m Gy) the level of school attendance and their results to the psycho-motor tests made during conscription medical examination. They noticed a diminution of 50% of the access success rate to university for the children having received an irradiation dose of 250 mG. No effect is noticed under the irradiation dose of 100 mGy. In their conclusions the authors compare these irradiation doses to these ones delivered in brain scanner examination. These results seem overestimated compared with the work made on fetuses ( publication 84 of ICRP) then the fetus is considered as more sensitive to ionizing radiations than the infant. The dose of 120 mGy is found in the literature and now the dose delivered in pediatrics are in the area of 0 and 100 mGy where no effect has been revealed in the cohort of irradiated children. The article does not include the principle of justification that is used nowadays and the replacement by the trans fontanel echography has allowed to reduce the number of brain scanner, used only for limited cases where the benefit is superior the the risk of irradiation. (N.C.)

  7. Practice specific model regulations: Radiation safety of non-medical irradiation facilities. Interim report for comment

    International Nuclear Information System (INIS)

    2003-08-01

    the infrastructure aimed at achieving its maximum efficiency, and extensively covers performance regulations. The BSS cover the application of ionizing radiation for all practices and interventions and are, therefore, basic and general in nature. Users must apply these basic requirements to their own particular practices. In this context, the preamble of the BSS states that: 'The Regulatory Authority may need to provide guidance on how certain regulatory requirements are to be fulfilled for various practices, for example in regulatory guideline documents.' There are certain requirements that, when applied to specific practices, can be fulfilled through virtually only one practical solution. In these cases, the regulatory authority would use a 'shall' statement for this solution. To meet other requirements, there may be more than one option. In these cases the regulatory authority would usually indicate the recommended option with a 'should' statement, which implies that licensees may choose another alternative provided that the level of safety is equivalent. This distinction has been maintained in this 'model regulations' for irradiation facilities in order to facilitate the decision of regulatory authorities on the degree of obligation

  8. Creation of a plant for gamma-sterilization of the medical equipment and irradiation of industrial materials

    International Nuclear Information System (INIS)

    Maltceva, F.; Petukhov, V.; Chekushin, A.

    1996-01-01

    The purpose of the project. To create a powerful irradiation devices allowing to fulfill the irradiation of large-sized objects with dozes up to 4 Rad, and caring out the irradiation technologies by using of it. The basic tasks of the project and sequence of fulfillment. The realization of irradiating technologies is possible at WWR-K research reactor that is located near of Almaty . At the reactor complex, there are the means for creation powerful irradiating devices, and quite qualified personnel having the experience of works with radioactive materials is available. All of it allows, both for the staff and for the population living nearby, to have the radiation safety during of caring out of the work with the use of high intensive radioactive sources. Technical problems. The creation of plant has the following stages: - fulfilling of the calculation and design work; - caring out of mechanical works on manufacturing the irradiating devices, cartridges for irradiating sources and a hermetic tank for irradiated objects; - installation of devices, fulfilling of the tests; - purchasing or manufacturing of radioactive sources (-10-60); - loading of the sources into devices, and realization of measurements of the fields of gamma field inside the container; - making up the working instruction; - training of the personnel

  9. Sapphire capillary interstitial irradiators for laser medicine

    Science.gov (United States)

    Shikunova, I. A.; Dolganova, I. N.; Dubyanskaya, E. N.; Mukhina, E. E.; Zaytsev, K. I.; Kurlov, V. N.

    2018-04-01

    In this paper, we demonstrate instruments for laser radiation delivery based on sapphire capillary needles. Such sapphire irradiators (introducers) can be used for various medical applications, such as photodynamic therapy, laser hyperthermia, laser interstitial thermal therapy, and ablation of tumors of various organs. Unique properties of sapphire allow for effective redistribution of the heat, generated in biological tissues during their exposure to laser radiation. This leads to homogeneous distribution of the laser irradiation around the needle, and lower possibility of formation of the overheating focuses, as well as the following non-transparent thrombi.

  10. Pions in nuclei, from virtual-pion exchange to real-pion transfer

    International Nuclear Information System (INIS)

    Yamazaki, Toshimitsu.

    1988-07-01

    Tracing the work of Miyazawa on nuclear magnetic moments, we discuss possible experimental ways to see whether a real pion exists in nuclei or not. While virtual pions are known to play an important role in nuclei, as clarified experimentally from anomalous orbital g factors of nucleons in nuclei, nearly nothing is known for the behavior of real pions in nuclei. We have shown that deeply bound hybrid states of π - are expected to exist in heavy nuclei, which can be populated by ''pion transfer'' reactions. (author)

  11. Pion-pion interactions in particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Martin, B R; Morgan, D; Shaw, G

    1976-01-01

    The aim of the book is to review the experimental and theoretical work on the processes involving pion-pion interactions. Sources of information on pion-pion scattering are examined, including pion production, dipion exchange, and weak and electromagnetic interactions. The theory and models of pion-pion scattering are discussed with reference to fixed momentum transfer, partial wave amplitudes, models and phenomenology, dynamical and field theoretic models, finite-energy sum rules, duality and the Veneziano model, resonance spectra and lastly, predictions from current algebra.

  12. Design of extraction system on grid of plasma generator electrode for pulsed electron irradiator

    International Nuclear Information System (INIS)

    Agus Purwadi; Bambang Siswanto; Lely Susita RM; Suprapto; Anjar Anggraini H; Ihwanul Azis

    2016-01-01

    It has been carried out design and study of electron extraction particularly for obtaining the electron extraction current via grid on the Plasma Generator Chamber (PGC) caused by the existence of extraction voltage U_a. Electrons of plasma surface emitted to acceleration region through emission window and then extracted acceleration by extraction voltage U_a through foil window to atmospheric region for being applied to any target. Applied extraction voltage U_a on PEI device influences the forming and energy value of electron extraction current I_e then the PGC dimension influences the product of thermal electron emission current I_e_0. It has been determinated the PGC geometry and dimension of producing electron extraction current based on arc discharge plasma current to desire on any plasma density. From the calculation yield for the value of plasma density n_e = 78 x 10"1"0 cm"-"3 and the arc discharge current Id = 80 A (pulse width τ = 100µs) used the PGC size of (80 x 20 x 40) cm"3. Emission window area of (65 x 15) cm"2 located on the low part surface of PGC is covered by a grid sheet made of stainless steel of rectangular shape and the distance of one grid hole to another is 0,25 mm each others. Current value of I_e beside depends on plasma parameters also depends on the size of grid holes. The optimum of geometry and size is rectangular with its side size of p ≈ 0,50 mm with the plasma parameters optimum (density value n_e = 10"1"6 m"-"3 and electron temperature T_e = 6 eV). From the initial experiment yields obtained that the electron extraction efficiency value α = 37,25 % on extraction voltage V = 3 kV. (author)

  13. EDF energy generation UK transport of irradiated fuel

    Energy Technology Data Exchange (ETDEWEB)

    James, R. [EDF Energy, London, (United Kingdom)

    2015-07-01

    This paper give an overview of irradiated fuel transport in the UK. It describes the design of irradiated fuel flask used by EDF Energy; operational experience and good practices learnt from over 50 years of irradiated fuel transport. The AGRs can store approximately 9 months generation of spent fuel, hence the ability to transport irradiated fuel is vital. Movements are by road to the nearest railhead, typically less than 2 miles and then by rail to Sellafield, up to 400 miles, for reprocessing or long term storage. Road and rail vehicles are covered. To date in the UK: over 30,000 Magnox flask journeys and over 15,000 AGR A2 flask journeys have been carried out.

  14. Measurement of the 64Zn,47Ti(n,p) cross sections using a DD neutron generator for medical isotope studies

    Science.gov (United States)

    Voyles, A. S.; Basunia, M. S.; Batchelder, J. C.; Bauer, J. D.; Becker, T. A.; Bernstein, L. A.; Matthews, E. F.; Renne, P. R.; Rutte, D.; Unzueta, M. A.; van Bibber, K. A.

    2017-11-01

    Cross sections for the 47Ti(n,p)47Sc and 64Zn(n,p)64Cu reactions have been measured for quasi-monoenergetic DD neutrons produced by the UC Berkeley High Flux Neutron Generator (HFNG). The HFNG is a compact neutron generator designed as a "flux-trap" that maximizes the probability that a neutron will interact with a sample loaded into a specific, central location. The study was motivated by interest in the production of 47Sc and 64Cu as emerging medical isotopes. The cross sections were measured in ratio to the 113In(n,n‧)113mIn and 115In(n,n‧)115mIn inelastic scattering reactions on co-irradiated indium samples. Post-irradiation counting using an HPGe and LEPS detectors allowed for cross section determination to within 5% uncertainty. The 64Zn(n,p)64Cu cross section for 2.76-0.02+0.01 MeV neutrons is reported as 49.3 ± 2.6 mb (relative to 113In) or 46.4 ± 1.7 mb (relative to 115In), and the 47Ti(n,p)47Sc cross section is reported as 26.26 ± 0.82 mb. The measured cross sections are found to be in good agreement with existing measured values but with lower uncertainty (neutron sources for nuclear data measurements and potentially the production of radionuclides for medical applications.

  15. Pregnancy and medical irradiation. ICRP-84

    International Nuclear Information System (INIS)

    2001-01-01

    A translation to Spanish of the ICRP document number 84. The exposure to ionising radiation of pregnant patients and radiation workers is a relevant subject in radiation protection, concerning not only the prevention but also the estimation of the associated risks. Great anxiety and unnecessary termination of pregnancies may be the consequences of the lack of correlation between the perception of risks by the pregnant woman and the involved professionals and their real magnitude. The International Commission on Radiation Protection has edited in 2000 the document ICRP 84 'Pregnancy and Medical Irradiation', addressed to medical and sanitary personnel. This document has been written as a practical guide which describes the effects of prenatal exposure to ionising radiation , the dose-thresholds and their relationship with the gestational age. It includes occupationally exposed women, patients undergoing medical procedures and public members. Most of diagnostic procedures properly done do not imply induction of deterministic effects in embryo/fetus. Therapeutical procedures could be associated with significant risks of deterministic effects. Childhood cancer induction is an stochastic effect without threshold and every 'in utero' exposure will increase their probability. With the aim of facilitating the diffusion of this document in the Ibero-American community , the Argentine Society of Radiation Protection (SAR) and the Spanish Society of Radiation Protection (SEPR) have worked together to producing a spanish version of ICRP84 , that is now presented in this publication, authorized by the ICRP

  16. Sivers asymmetries for inclusive pion and kaon production in deep-inelastic scattering

    International Nuclear Information System (INIS)

    Ellis, John; Hwang, Dae Sung; Kotzinian, Aram

    2009-01-01

    We calculate the Sivers distribution functions induced by the final-state interaction due to one-gluon exchange in diquark models of a nucleon structure, treating the cases of scalar and axial-vector diquarks with both dipole and Gaussian form factors. We use these distribution functions to calculate the Sivers single-spin asymmetries for inclusive pion and kaon production in deep-inelastic scattering. We compare our calculations with the results of HERMES and COMPASS, finding good agreement for π + production at HERMES, and qualitative agreement for π 0 and K + production. Our predictions for pion and kaon production at COMPASS could be probed with increased statistics. The successful comparison of our calculations with the HERMES data constitutes prima facie evidence that the quarks in the nucleon have some orbital angular momentum in the infinite-momentum frame.

  17. Sivers Asymmetries for Inclusive Pion and Kaon Production in Deep-Inelastic Scattering

    CERN Document Server

    Ellis, Jonathan Richard; Kotzinian, Aram

    2009-01-01

    We calculate the Sivers distribution functions induced by the final-state interaction due to one-gluon exchange in diquark models of nucleon structure, treating the cases of scalar and axial-vector diquarks with both dipole and Gaussian form factors. We use these distribution functions to calculate the Sivers single-spin asymmetries for inclusive pion and kaon production in deep-inelastic scattering. We compare our calculations with the results of HERMES and COMPASS, finding good agreement for pi+ production at HERMES, and qualitative agreement for pi0 and K+ production. Our predictions for pion and kaon production at COMPASS could be probed with increased statistics. The successful comparison of our calculations with the HERMES data constitutes prima facie evidence that the quarks in the nucleon have some orbital angular momentum in the infinite-momentum frame.

  18. Laser Radiation Pressure Accelerator for Quasi-Monoenergetic Proton Generation and Its Medical Implications

    Science.gov (United States)

    Liu, C. S.; Shao, X.; Liu, T. C.; Su, J. J.; He, M. Q.; Eliasson, B.; Tripathi, V. K.; Dudnikova, G.; Sagdeev, R. Z.; Wilks, S.; Chen, C. D.; Sheng, Z. M.

    Laser radiation pressure acceleration (RPA) of ultrathin foils of subwavelength thickness provides an efficient means of quasi-monoenergetic proton generation. With an optimal foil thickness, the ponderomotive force of the intense short-pulse laser beam pushes the electrons to the edge of the foil, while balancing the electric field due to charge separation. The electron and proton layers form a self-organized plasma double layer and are accelerated by the radiation pressure of the laser, the so-called light sail. However, the Rayleigh-Taylor instability can limit the acceleration and broaden the energy of the proton beam. Two-dimensional particle-in-cell (PIC) simulations have shown that the formation of finger-like structures due to the nonlinear evolution of the Rayleigh-Taylor instability limits the acceleration and leads to a leakage of radiation through the target by self-induced transparency. We here review the physics of quasi-monoenergetic proton generation by RPA and recent advances in the studies of energy scaling of RPA, and discuss the RPA of multi-ion and gas targets. The scheme for generating quasi-monoenergetic protons with RPA has the potential of leading to table-top accelerators as sources for producing monoenergetic 50-250 MeV protons. We also discuss potential medical implications, such as particle therapy for cancer treatment, using quasi-monoenergetic proton beams generated from RPA. Compact monoenergetic ion sources also have applications in many other areas such as high-energy particle physics, space electronics radiation testing, and fast ignition in laser fusion.

  19. Mechanism for coherent production of pions from the decay of resonances

    International Nuclear Information System (INIS)

    Lam, C.S.; Lo, S.Y.

    1984-01-01

    Conditions and signatures for the induced emission of bosons from a microscopic device are discussed. Detailed formulae for a simple two-level model are derived. In this model the decay of N Δ-resonances residing in a microscopic volume V is discussed. It is shown that large amplification factors for unusual charge bunching of pions are obtained as a result of induced emissions

  20. Nuclear Targets for a Precision Measurement of the Neutral Pion Radiative Width

    International Nuclear Information System (INIS)

    Martel, Philippe; Clinton, Eric; McWilliams, R.; Lawrence, Dave; Miskimen, Rory; Ahmidouch, Abdellah; Ambrozewicz, Pawel; Asaturyan, Arshak; Baker, O.; Benton, LaRay; Bernstein, Aron; Cole, Philip; Collins, Patrick; Dale, Daniel; Danagoulian, Samuel; Davidenko, G.; Demirchyan, Raphael; Deur, Alexandre; Dolgolenko, A.; Dzyubenko, Georgiy; Evdokimov, Anatoly; Feng, JIng; Gabrielyan, Marianna; Gan, Liping; Gasparian, Ashot; Glamazdin, Oleksandr; Goryachev, Vladimir; Gyurjyan, Vardan; Hardy, K.; Ito, Mark; Khandaker, Mahbubul; Kingsberry, Paul; Kolarkar, Ameya; Konchatnyi, Mykhailo; Korchin, O.; Korsch, Wolfgang; Kowalski, Stanley; Kubantsev, Mikhail; Kubarovsky, Valery; Larin, Ilya; Matveev, V.; McNulty, Dustin; Milbrath, Brian; Minehart, Ralph; Mochalov, Vasiliy; Mtingwa, Sekazi; Nakagawa, Itaru; Overby, Steven; Pasyuk, Evgueni; Payen, Marvin; Pedroni, Ronald; Prok, Yelena; Ritchie, Barry; Salgado, Carlos; Sitnikov, Anatoly; Sober, Daniel; Stephens, W.; Teymurazyan, Aram; Underwood, Jarreas; Vasiliev, A.; Verebryusov, V.; Vishnyakov, Vladimir; Wood, Michael

    2009-01-01

    A technique is presented for precision measurements of the area densities, density * T, of approximately 5% radiation length carbon and 208Pb targets used in an experiment at Jefferson Laboratory to measure the neutral pion radiative width. The precision obtained in the area density for the carbon target is +/- 0.050%, and that obtained for the lead target through an x-ray attenuation technique is +/- 0.43%.

  1. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    International Nuclear Information System (INIS)

    Abat, E; Arik, E; Abdallah, J M; Addy, T N; Adragna, P; Aharrouche, M; Ahmad, A; Akesson, T P A; Aleksa, M; Anghinolfi, F; Baron, S; Alexa, C; Anderson, K; Andreazza, A; Banfi, D; Antonaki, A; Arabidze, G; Atkinson, T; Baines, J; Baker, O K

    2011-01-01

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20GeV and 180GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.

  2. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    Energy Technology Data Exchange (ETDEWEB)

    Abat, E; Arik, E [Bogazici University, Faculty of Sciences, Department of Physics, TR - 80815 Bebek-Istanbul (Turkey); Abdallah, J M [Institut de Fisica d' Altes Energies, IFAE, Universitat Autonoma de Barcelona, Edifici Cn, ES - 08193 Bellaterra (Barcelona) Spain (Spain); Addy, T N [Hampton University, Department of Physics, Hampton, VA 23668 (United States); Adragna, P [Queen Mary, University of London, Mile End Road, E1 4NS, London (United Kingdom); Aharrouche, M [Universitaet Mainz, Institut fuer Physik, Staudinger Weg 7, DE 55099 (Germany); Ahmad, A [Insitute of Physics, Academia Sinica, TW - Taipei 11529, Taiwan (China); Akesson, T P A [Lunds universitet, Naturvetenskapliga fakulteten, Fysiska institutionen, Box 118, SE - 221 00, Lund (Sweden); Aleksa, M; Anghinolfi, F; Baron, S [European Laboratory for Particle Physics CERN, CH-1211 Geneva 23 (Switzerland); Alexa, C [National Institute of Physics and Nuclear Engineering (Bucharest -IFIN-HH), P.O. Box MG-6, R-077125 Bucharest (Romania); Anderson, K [University of Chicago, Enrico Fermi Institute, 5640 S. Ellis Avenue, Chicago, IL 60637 (United States); Andreazza, A; Banfi, D [INFN Sezione di Milano, via Celoria 16, IT - 20133 Milano (Italy); Antonaki, A; Arabidze, G [University of Athens, Nuclear and Particle Physics Department of Physics, Panepistimiopouli Zografou, GR 15771 Athens (Greece); Atkinson, T [School of Physics, University of Melbourne, AU - Parkvill, Victoria 3010 (Australia); Baines, J [Rutherford Appleton Laboratory, Science and Technology Facilities Council, Harwell Science and Innovation Campus, Didcot OX11 0QX (United Kingdom); Baker, O K, E-mail: kjg@particle.kth.se [Yale University, Department of Physics , PO Box 208121, New Haven, CT06520-8121 (United States)

    2011-06-15

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20GeV and 180GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.

  3. Pion-pion scattering

    International Nuclear Information System (INIS)

    Kuehnelt, H.

    1975-01-01

    We discuss a few properties of scattering amplitudes proved within the framework of the field theory and their significance in the derivation of quantitative statements. The state of the boundaries for the scattering lengths is to be especially discussed as well as the question as to how far it is possible to exclude various solutions from phase displacement analyses. (orig./LH) [de

  4. An improved optical potential for low-energy pion-nucleus scattering

    International Nuclear Information System (INIS)

    Khankhasaev, M.Kh.; Topil'skaya, N.S.

    1988-01-01

    A new procedure for calculating the imaginary part the of Stricker, McManus and Carr (SMC) optical potential is proposed. It is based on an approximate expression for the pion-nucleon scattering amplitude including nuclear structure effects. It is shown that the resulting potential with the absorption parameters fitted to the pionic atom data provides a good description of the scattering up to 50 MeV

  5. Evidence for longitudinal photon polarization in muon-pair production by pions

    International Nuclear Information System (INIS)

    Anderson, K.J.; Coleman, R.N.; Karhi, K.P.; Newman, C.B.; Pilcher, J.E.; Rosenberg, E.I.; Thaler, J.J.; Hogan, G.E.; McDonald, K.T.; Sanders, G.H.; Smith, A.J.S.

    1979-01-01

    Data on μ-pair production by pions are examined as a function of x and P/sub T/ for longitudinal photon polarization. Evidence in the form of a sin 2 theta* term in the helicity angular distribution is observed for x near 1. This is conclusive evidence that production in this region is not predominantly through on-shell quark annihilation. The result is consistent with a calculation based on quantum chromodynamics

  6. Off-shell form factors in the soft photon limit for pion photoproduction

    International Nuclear Information System (INIS)

    Chumbalov, A.A.; Kamalov, S.S.

    1991-01-01

    The low energy theorems for the pion photoproduction are considered on the basis of the Adler-Dothan procedure. It is shown that the soft photon limit necessarily leads to the Born approximation for the π 0 -photoproduction amplitude at the threshold. All additional terms, according to the Adler-Dothan recipe, are to be neglected in the derivation of the LET. 5 refs.; 2 figs

  7. Food processing with electrically generated photon irradiation

    International Nuclear Information System (INIS)

    Matthews, S.M.

    1985-01-01

    Economic constraints require that a food irradiation processing facility have a throughput of approximately 1 MGy ton/day (0.91 MGy m.t./day) requiring 3 MegaCuries (MCi) of cobalt-60 at each site. This requirement means that the total world amount of cobalt-60 would have to be increased by about 60 percent just to handle the California almond and raisin crop during peak season. It is doubtful that public opinion would allow the increased distribution of radioactive isotopes, with the resultant burden upon the transportation networks, as a price to be paid to eat irradiated food. Electric sources have characteristics that allow the production of more penetrating, uniform, and efficient radiation that is available from nuclear isotopes. The heart of the electric radiation source is the electron accelerator. At present, there are no accelerators commercially available that can meet the requirements for food irradiation processing. However, the U.S. Department of Defense-funded beam weapons programs have provided a very promising accelerator technology at the Lawrence Livermore National Laboratory. If this technology were to be commercialized, it appears that the required accelerators would be available for US$1.5 million apiece, and quite possibly for less than this amount. A conceptual design for a portable electric food irradiation processing machine is presented and analyzed for cost, assuming the required accelerators are available for $1.5 million each. It is shown that food can be processed for 1 kGy for a price of $5.98/ton ($6.59/m.t.)

  8. Pion beam development for the LAMPF biomedical project

    International Nuclear Information System (INIS)

    Paciotti, M.; Amols, H.; Bradbury, J.; Rivera, O.; Hogstrom, K.; Smith, A.; Inoue, H.; Laubacher, D.; Sandford, S.

    1979-01-01

    Common to both static and dynamic patient irradiations at the LAMPF linac is the problem of maintaining good quality control of beams form a secondary channel. A major contributor to therapy beam variation has been change in electron contamination due to the change in target geometry and proton beam steering. The electron variation problem is described and a solution is presented that has been realized as a result o a new target geometry that allows some control of the electron fraction

  9. Experiments on exclusive proton and pion scattering for nuclear filtering and color transparency study

    International Nuclear Information System (INIS)

    Wu, J.

    1992-01-01

    The color transparency of pions in various nuclei has been measured and compared with the proton transparency. The measurement results are consistent with semi-classical predictions that the pion transparency is larger than the proton transparency at the same incident momentum and their ratio becomes larger as the nucleus becomes heavier. The energy dependence of the transparency has been studied based on the semi-classical theory and the result shows that the transparency can be written into two factors. The physics interpretations of the two factors have been discussed. A new experimental apparatus, the Exclusive Variable Apparatus (EVA) at Brookhaven National Laboratory, along with unique electronic techniques chosen for enabling the EVA trigger system to fulfill physics requirements of the experiment, have been described

  10. Search for low mass exotic baryons in one pion electroproduction data measured at JLAB

    International Nuclear Information System (INIS)

    Tatischeff, B.; Tomasi-Gustafsson, E.

    2007-02-01

    This paper aims to give further evidence for the existence of low mass exotic baryons. Narrow structures in baryonic missing mass or baryonic invariant mass were previously observed during the last ten years. Since their existence is sometimes questionable, the structure functions of one pion electroproduction cross sections, measured at JLAB, are studied to add information on the possible existence of these narrow exotic baryonic resonances. (authors)

  11. Single nucleon-nucleon collision model for subthreshold pion production in heavy ion collisions

    International Nuclear Information System (INIS)

    Bellini, V.; Di Toro, M.; Bonasera, A.

    1985-01-01

    We show that inclusive experimental data on subthreshold pion production in 12 C + 12 C and 16 O + 12 C collisions can be reproduced using a first chance Nucleon-Nucleon (NN) collision mechanism. Pauli blocking effects are extremely important while π-resorption can be safely neglected for these light systems. We apply our method at various beam energies. The possible importance of collective dynamical effects around the physical threshold is finally suggested

  12. Pion production - a probe for coherence in medium energy heavy ion collisions

    International Nuclear Information System (INIS)

    Stachel, J.

    1985-01-01

    Neutral pion production is observed in heavy ion collisions at beam energies as low as 25 MeV/u, where this process is consumming the major portion of the total center of mass energy available. At these low beam energies single nucleon nucleon collision models and also models that incorporate the cooperative sharing of the beam energy of several nucleons do not reproduce the data. Rather, the data presented here call for a fully coherent production mechanism. (orig.)

  13. Search for resonance structures in inclusive charged pion spectra from p-barp annihilation at rest

    International Nuclear Information System (INIS)

    Angelopoulos, A.; Apostolakis, A.; Papaelias, P.

    1985-01-01

    The charged pion momentum spectra from p-barp annihilation at rest have been measured with high statistics. A search for structures finds four narrow lines which are identified with the absorption and decay processes of kaons stopping in the target. Limits of 1-6 x 10 -4 /p-bar (90% C.L.) are placed on the yield of a narrow state in the mass range 1000--1660 MeV

  14. Quark bag coupling to finite size pions

    International Nuclear Information System (INIS)

    De Kam, J.; Pirner, H.J.

    1982-01-01

    A standard approximation in theories of quark bags coupled to a pion field is to treat the pion as an elementary field ignoring its substructure and finite size. A difficulty associated with these treatments in the lack of stability of the quark bag due to the rapid increase of the pion pressure on the bad as the bag size diminishes. We investigate the effects of the finite size of the qanti q pion on the pion quark bag coupling by means of a simple nonlocal pion quark interaction. With this amendment the pion pressure on the bag vanishes if the bag size goes to zero. No stability problems are encountered in this description. Furthermore, for extended pions, no longer a maximum is set to the bag parameter B. Therefore 'little bag' solutions may be found provided that B is large enough. We also discuss the possibility of a second minimum in the bag energy function. (orig.)

  15. Pion correlations and calorimeter design for high energy heavy ion collisions. Progress report

    International Nuclear Information System (INIS)

    Wolf, K.L.

    1997-01-01

    Data analysis is in progress for recent experiments performed by the NA44 collaboration with the first running of 160 A GeV 208 Pb-induced reactions at the CERN SPS. Identified singles spectra were taken for pions, kaons, protons, deuterons, antiprotons and antideuterons. Two-pion interferometry measurements were made for semi-central-triggered 208 Pb + Pb collisions. An updated multi-particle spectrometer allows high statistics data sets of identified particles to be collected near mid-rapidity. A second series of experiments will be performed in the fall of 1995 with more emphasis on identical kaon interferometry and on the measurement of rare particle spectra and correlations. Modest instrumentation upgrades by TAMU are designed to increase the trigger function for better impact parameter selection and improved collection efficiency of valid events. An effort to achieve the highest degree of projectile-target stopping is outlined and it is argued that an excitation function on the SPS is needed to better understand reaction mechanisms. Analysis of experimental results is in the final stages at LBL in the EOS collaboration for two-pion interferometry in the 1.2 A GeV Au + Au reaction, taken with full event characterization

  16. Pion condensation in symmetric nuclear matter

    International Nuclear Information System (INIS)

    Kabir, K.; Saha, S.; Nath, L.M.

    1987-09-01

    Using a model which is based essentially on the chiral SU(2)xSU(2) symmetry of the pion-nucleon interaction, we examine the possibility of pion condensation in symmetric nucleon matter. We find that the pion condensation is not likely to occur in symmetric nuclear matter for any finite value of the nuclear density. Consequently, no critical opalescence phenomenon is expected to be seen in the pion-nucleus interaction. (author). 20 refs

  17. Pion condensation in symmetric nuclear matter

    Science.gov (United States)

    Kabir, K.; Saha, S.; Nath, L. M.

    1988-01-01

    Using a model which is based essentially on the chiral SU(2)×SU(2) symmetry of the pion-nucleon interaction, we examine the possibility of pion condensation in symmetric nucleon matter. We find that the pion condensation is not likely to occur in symmetric nuclear matter for any finite value of the nuclear density. Consequently, no critical opalescence phenomenom is expected to be seen in the pion-nucleus interaction.

  18. Preclinical experiments for analysis of tumor regression due to negative pions

    International Nuclear Information System (INIS)

    Blattmann, H.; Cabeza, L.; Fritz-Niggli, H.

    To test the potential therapeutic value of negative pions in comparison with conventional x-rays, cobalt-60 γ rays, and high energy electrons and photons (Betatron), experimental analyses with induced tumors (transplant tumors) after irradiation are to be performed in vivo and in vitro (tumor cell suspensions, cell cultures, spontaneous tumors, carcinoma in ascites form); in addition to tumors primarily of mice, human cell tumors will be used; studies will also be made of cell kinetics with various cell types (normal cells, transformed (malignant) cells, beam-resistant, beam-sensitive types) using cell cultures from Chinese hamsters. An attempt will be made to compare slow- and fast-growing tumors. In a second phase, human tumors in conditioned animals will be tested in situ or as cell cultures. Skin, small intestine, regenerating liver and kidney, together with cell cultures, will serve as normal reaction systems

  19. Results from pion calibration runs for the H1 liquid argon calorimeter and comparisons with simulations

    International Nuclear Information System (INIS)

    Andrieu, B.; Ban, J.; Barrelet, E.; Bergstein, H.; Bernardi, G.; Besancon, M.; Binder, E.; Blume, H.; Borras, K.; Boudry, V.; Brasse, F.; Braunschweig, W.; Brisson, V.; Campbell, A.J.; Carli, T.; Colombo, M.; Coutures, C.; Cozzika, G.; David, M.; Delcourt, B.; DelBuono, L.; Devel, M.; Dingus, P.; Drescher, A.; Duboc, J.; Duenger, O.; Ebbinghaus, R.; Egli, S.; Ellis, N.N.; Feltesse, J.; Feng, Y.; Ferrarotto, F.; Flauger, W.; Flieser, M.; Gamerdinger, K.; Gayler, J.; Godfrey, L.; Goerlich, L.; Goldberg, M.; Graessler, R.; Greenshaw, T.; Greif, H.; Haguenauer, M.; Hajduk, L.; Hamon, O.; Hartz, P.; Haustein, V.; Haydar, R.; Hildesheim, W.; Huot, N.; Jabiol, M.A.; Jacholkowska, A.; Jaffre, M.; Jung, H.; Just, F.; Kiesling, C.; Kirchhoff, T.; Kole, F.; Korbel, V.; Korn, M.; Krasny, W.; Kubenka, J.P.; Kuester, H.; Kurzhoefer, J.; Kuznik, B.; Lander, R.; Laporte, J.F.; Lenhardt, U.; Loch, P.; Lueers, D.; Marks, J.; Martyniak, J.; Merz, T.; Naroska, B.; Nau, A.; Nguyen, H.K.; Niebergall, F.; Oberlack, H.; Obrock, U.; Ould-Saada, F.; Pascaud, C.; Pyo, H.B.; Rauschnabel, K.; Ribarics, P.; Rietz, M.; Royon, C.; Rusinov, V.; Sahlmann, N.; Sanchez, E.; Schacht, P.; Schleper, P.; Schlippe, W. von; Schmidt, C.; Schmidt, D.; Shekelyan, V.; Shooshtari, H.; Sirois, Y.; Staroba, P.; Steenbock, M.; Steiner, H.; Stella, B.; Straumann, U.; Turnau, J.; Tutas, J.; Urban, L.; Vallee, C.; Vecko, M.; Verrecchia, P.; Villet, G.; Vogel, E.; Wagener, A.; Wegener, D.; Wegner, A.; Wellisch, H.P.; Yiou, T.P.; Zacek, J.; Zeitnitz, Ch.; Zomer, F.

    1993-01-01

    We present results on calibration runs performed with pions at CERN SPS for different modules of the H1 liquid argon calorimeter which consists of an electromagnetic section with lead absorbers and a hadronic section with steel absorbers. The data cover an energy range from 3.7 to 205 GeV. Detailed comparisons of the data and simulation with GHEISHA 8 in the framework of GEANT 3.14 are presented. The measured pion induced shower profiles are well described by the simulation. The total signal of pions on an energy scale determined from electron measurements is reproduced to better than 3% in various module configurations. After application of weighting functions, determined from Monte Carlo data and needed to achieve compensation, the reconstructed measured energies agree with simulation to about 3%. The energies of hadronic showers are reconstructed with a resolution of about 50%/√E + 2%. This result is achieved by inclusion of signals from an iron streamer tube tail catcher behind the liquid argon stacks. (orig.)

  20. Development of lesions resulting from acute localised irradiation in the pig: trials for medical and surgical management

    International Nuclear Information System (INIS)

    Daburon, F.; Lefaix, J.L.; Remy, J.; Bolnot, D.; Guilbaud, J.

    1986-01-01

    Medical and surgical treatments were tested on pigs on which the thigh has been irradiated locally with single doses of 30, 40, 64 or 84 Gy (2 cm depth-dose) from an Ir 192 source. The association of non-steroidal anti-inflammatory compounds (flurbiprofen, niflumic acid) and platelet anti-aggregants (bencyclane, pyridinol carbamate) (i) decreased the local thermal reaction evaluated by microwave thermography, (ii) slowed down the chronological evolution of the lesions by several days, in a way comparable to a decrease in the dose, and (iii) limited to a certain extent the development of the lesion, especially the fibrotic extension when scarring was seen, i.e. after 30-40 Gy. Early surgery of irradiated tissues with doses higher than 25-30 Gy appeared to be well tolerated with regard to both immediate healing and the evolution of late fibrosis. (author)

  1. Secondary particle tracks generated by ion beam irradiation

    Science.gov (United States)

    García, Gustavo

    2015-05-01

    The Low Energy Particle Track Simulation (LEPTS) procedure is a powerful complementary tool to include the effect of low energy electrons and positrons in medical applications of radiation. In particular, for ion-beam cancer treatments provides a detailed description of the role of the secondary electrons abundantly generated around the Bragg peak as well as the possibility of using transmuted positron emitters (C11, O15) as a complement for ion-beam dosimetry. In this study we present interaction probability data derived from IAM-SCAR corrective factors for liquid environments. Using these data, single electron and positron tracks in liquid water and pyrimidine have been simulated providing information about energy deposition as well as the number and type of interactions taking place in any selected ``nanovolume'' of the irradiated area. In collaboration with Francisco Blanco, Universidad Complutense de Madrid; Antonio Mu noz, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas and Diogo Almeida, Filipe Ferreira da Silva, Paulo Lim ao-Vieira, Universidade Nova de Lisboa. Supported by the Spanish and Portuguese governments.

  2. Aerosol generation and delivery in medical applications

    International Nuclear Information System (INIS)

    Soni, P.S.; Raghunath, B.

    1998-01-01

    It is well established that radioaerosol lung technique by inhalation is a very versatile technique in the evaluation of health effects and medical diagnostic applications, especially to detect chronic obstructive pulmonary diseases, their defence mechanism permeability and many others. Most important part of aerosol technology is to generate reproducibly stable diagnostic radioaerosols of known characteristics. Many compressed air atomisers are commercially available for generating aerosols but they have limited utility in aerosol inhalation, either because of large droplet size, low aerosol output or high airflow rates. There is clearly a need for a versatile and economical aerosol generation/inhalation system that can produce dry labelled aerosol particles with high deep lung delivery efficiency suitable for clinical studies. BARC (Bhabha Atomic Research Centre) has developed a dry aerosol generation/delivery system which operates on compressed air and generates dry polydisperse aerosols. This system is described along with an assessment of the aerosol characteristics and efficiency for diagnosis of various respiratory disorders

  3. The Next Generation Precision Medical Record - A Framework for Integrating Genomes and Wearable Sensors with Medical Records

    OpenAIRE

    Batra, Prag; Singh, Enakshi; Bog, Anja; Wright, Mark; Ashley, Euan; Waggott, Daryl

    2016-01-01

    Current medical records are rigid with regards to emerging big biomedical data. Examples of poorly integrated big data that already exist in clinical practice include whole genome sequencing and wearable sensors for real time monitoring. Genome sequencing enables conventional diagnostic interrogation and forms the fundamental baseline for precision health throughout a patients lifetime. Mobile sensors enable tailored monitoring regimes for both reducing risk through precision health intervent...

  4. Biological risks of medical irradiations: Medical physics monograph 5

    International Nuclear Information System (INIS)

    Fullerton, G.D.; Kopp, D.T.; Waggener, R.G.; Webster, E.W.

    1980-01-01

    This book is the fifth in a series of monographs by the American Association of Physicists in Medicine (AAPM) and is a compendium of papers presented at an AAPM regional symposium conducted in San Antonio in July 1980. The book is divided into three sections: (1) biological fundamentals of ionizing radiation, (2) risk evaluation and reduction in three principle radiologic subspecialties (diagnostic radiology, nuclear medicine and radiation therapy), and (3) medical-legal implications. The first section includes a historical review of radiation biology, including a discussion of somatic and genetic effects and statistical approaches to risk estimates. The section on risk evaluation and reduction includes a good review of the units of exposure and activity including the international (SI) system employing the gray, becquerel, and seivert that respectively replace the rad, Curie, and rem. The unavoidable problem of legal responsibility and liability is the subject of the third, and last, section of the monograph. A chapter summarizing the legal history of medical irradiation also includes a glossary of pertinent legal terms. Recent court decisions that impact upon the clinical use of radiation are presented and discussed as well as proposed changes in federal guidelines that could have a large impact on the practice of medicine in general and radiology in particular

  5. Selection and acquisition of data for the measurement of the spin rotation parameters in pion-proton scattering at high energies

    International Nuclear Information System (INIS)

    Raoul, Jean-Claude

    1971-01-01

    The experiment consists in measuring the polarisation of the recoil protons from elastic scattering of positive or negative pions on a polarised proton target (L. M. N.). The polarimeter consists in carbon plates alternated with wire spark chambers, The associated electronics has the following main functions: selective triggering of the spark chambers, acquisition and transcription on magnetic tape of all relevant information, continuous check of the various parts of the equipment. About one hundred scintillation counters provide information on the geometry of the pion-proton scattering. A fast logic treats these information. This logic, made of integrated circuits MECL, generates the selective trigger with a transit time of less than 150 ns, it reduces the triggering rate on background events by almost one order of magnitude. A small computer is used for acquisition and transcription of the data, and for the control of the experiment. (author) [fr

  6. Questionnaire survey and technical guideline of blood irradiation on medical facilities

    International Nuclear Information System (INIS)

    Matsumoto, Mitsuhiro; Hasegawa, Hironori; Okumura, Masahiko; Sonoda, Tatsuo; Osada, Koji.

    1997-01-01

    We know that transfusion-associated graft versus host disease (TA-GVHD) is a serious side effect associated with blood transfusion and the onset is independent on the immunological conditions of patients. We have only prophylactic treatment against TA-GVHD. The most reliable method is to irradiate the blood for transfusion. In Japanese medical facilities, however, the risk of TA-GVHD is poorly understood and actual conditions of the blood irradiation are unclear. We sent a questionnaire to randomly selected 426 medical facilities in Japan, which had the department of radiology, to investigate the actual conditions of blood irradiation for transfusion and the problems on the irradiation dose measurement of the external apparatus for blood irradiation. The questionnaire involved 19 questions about the blood irradiation for transfusion. The survey took place for one month (June 1-June 30, 1995). Replies were obtained from a total of 306 medical facilities (72%). The results showed that blood irradiation was done by several methods in the 75% of the medical facilities, and the external irradiation apparatus was used in 83%. Some problems were shown, including irradiation period, cost of the irradiation, the operating procedure of the apparatus, requested number of the irradiation, and the request after usual hours. There was no significant problem on the irradiation dose, irradiation method, etc. We also sent a questionnaire to 74 facilities of the Red Cross Blood Center, in which the frequency of blood irradiation have increased since May, 1976. The X-ray apparatus as the external irradiation apparatus has practical advantages; lower cost, compact and out of the legal control on the ionizing radiation, however, it has some problems on the uniformity of the absorption dose when a single X-ray tube-type apparatus is used. We discuss about the possible onset of TA-GVHD or other accidents by the incorrect irradiation of the blood preparations. (K.H.)

  7. Computer simulations analysis for determining the polarity of charge generated by high energy electron irradiation of a thin film

    DEFF Research Database (Denmark)

    Malac, Marek; Hettler, Simon; Hayashida, Misa

    2017-01-01

    Detailed simulations are necessary to correctly interpret the charge polarity of electron beam irradiated thin film patch. Relying on systematic simulations we provide guidelines and movies to interpret experimentally the polarity of the charged area, to be understood as the sign of the electrost......Detailed simulations are necessary to correctly interpret the charge polarity of electron beam irradiated thin film patch. Relying on systematic simulations we provide guidelines and movies to interpret experimentally the polarity of the charged area, to be understood as the sign...... of the electrostatic potential developed under the beam with reference to a ground electrode. We discuss the two methods most frequently used to assess charge polarity: Fresnel imaging of the irradiated area and Thon rings analysis. We also briefly discuss parameter optimization for hole free phase plate (HFPP...

  8. Two-Pion Correlation Measurements for 14.6 A.GEV/C SILICON-28 + X and 11.6 A.GEV/C GOLD-197 + Gold.

    Science.gov (United States)

    Soltz, Ron A.

    Two-pion correlation functions have been measured in the central rapidity regions (1.5 < y < 2.0) for 14.6 A cdot GeV/c Si+Au to 2 pi^-+rm X (central and peripheral), Si+Al to 2pi^++ rm X (central and minimum bias), Si+Au to 2pi^++rm X (central), and 11.6 A cdot GeV/c Au+Au to 2pi^ -+rm X (central) systems. Two-dimensional fits in R-tau and R_{T}-R_ {L} were performed for these systems for different cuts in the total charged particle multiplicity and forward energy. The R, R_{T}, and R_{L} radius parameters for systems involving the Si projectile were found to increase with increasing charged particle multiplicity. These parameters were observed to scale linearly with A _sp{pp}{1/3}, where A_{pp} is the number of projectile participants as calculated from the forward energy deposition. The correlation functions were also fit to several three-dimensional functions. In all cases these fits proved to be consistent with the results of the two-dimensional fits. Events generated from the RQMD cascade code indicate that pions within experimental acceptance are produced from a region that is smaller than the entire region of pion production. A direct measure of the RQMD source for pions within the acceptance show qualitative agreement with the observed scaling. A minimization function was developed which is derived from the Poisson fluctuations in both the actual and background distributions. Progress was made in understanding the errors of event-mixed background distributions. An empirical study confirms that fluctuations within a bin are indeed Poisson for typical backgrounds generated during this analysis. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617 -253-5668; Fax 617-253-1690.).

  9. Cross sections for pion, proton, and heavy-ion production from 800 MeV protons incident upon aluminum and silicon

    Energy Technology Data Exchange (ETDEWEB)

    Dicello, J.F. (Clarkson Univ., Potsdam, NY (USA)); Schillaci, M.E.; Liu Lonchang (Los Alamos National Lab., NM (USA))

    1990-01-01

    When high-energy cosmic rays interact with electronics or other materials in a spacecraft, including the occupants themselves, pions are produced as secondary particles. These secondary pions interact further in the materials producing nuclear secondaries, including nuclear recoils and heavy-ion tertiaries. The secondary pions and the the tertiary particles are capable of producing single-event upsets and other damage in integrated circuits and damage in biological systems. Negative pions stopping in materials are particularly effective because of their unique ability to produce short-range heavy particles from pion stars. With the Los Alamos National Laboratory's version of the intranuclear cascade evaporation code, VEGAS, we have calculated the number of pions produced per energy interval per incident proton from 800 MeV protons on aluminum-27 and silicon-28 along with corresponding results for neutrons, protons, and heavier ions. (orig.).

  10. Two-arm semiconductor spectrometer for charged particles for the investigation of absorption by nuclei of stopped negative pions

    International Nuclear Information System (INIS)

    Gornov, M.G.; Gurov, Yu.B.; Lukin, A.S.; Morokhov, P.V.; Pechkurov, V.A.; Pichugin, A.P.; Saveliev, V.I.; Shafigullin, R.R.; Sergeev, F.M.; Khomutov, A.A.; Oganesian, K.O.; Osipenko, B.P.; Sandukovsky, V.G.

    1984-01-01

    A two-arm semiconductor spectrometer for the detection of secondary charged particles, such as p, d, t, 3 He, 4 He and of their correlations in the process of stopped pion absorption by nuclei is described. The spectrometer consists of two telescopes of Si-detectors with a sensitive surface of 800 mm 2 , two semiconductor detectors as monitors and the 'live' target, a silicon surface barrier detector. The number of semiconductor detectors is 19. A technique for pion stop selection in thin targets is described. The problem of particle identification and of measurements of their energy with the help of a multicrystal semiconductor telescope is discussed. The technique provides an absolute normalization of spectra. The 'alive' target helps to obtain more information on the process of pion absorption by Si-nuclei. (orig.)

  11. Measurement of the pion form factor

    International Nuclear Information System (INIS)

    Dally, E.; Hauptman, J.; May, C.

    1977-01-01

    The pion form factor has been measured in the momentum transfer range of 0.03( 2 by scattering pions from atomic electrons in a liquid hydrogen target. The pion form factor is defined to be the elastic scattering cross section divided by that predicted for a point pion. The experiment has been performed in a 100 GeV/c negative pion beam incident on a 50 cm liquid hydrogen target at Fermi laboratory. The corrected form factor equals 0.33+-0.06 f 2 . Vector dominance predicts 0.40 f 2

  12. Pion condensation in symmetric nuclear matter

    International Nuclear Information System (INIS)

    Shamsunnahar, T.; Saha, S.; Kabir, K.; Nath, L.M.

    1991-01-01

    We have investigated the possibility of pion condensation in symmetric nuclear matter using a model of pion-nucleon interaction based essentially on chiral SU(2) x SU(2) symmetry. We have found that pion condensation is not possible for any finite value of the density. Consequently, no critical opalescence phenomenon is likely to be seen in pion-nucleus scattering nor is it likely to be possible to explain the EMC effect in terms of an increased number of pions in the nucleus. (author)

  13. Twist-2 Light-Cone Pion Wave Function

    OpenAIRE

    Belyaev, V. M.; Johnson, Mikkel B.

    1997-01-01

    We present an analysis of the existing constraints for the twist-2 light-cone pion wave function. We find that existing information on the pion wave function does not exclude the possibility that the pion wave function attains its asymptotic form. New bounds on the parameters of the pion wave function are presented.

  14. Medical Image Processing for Fully Integrated Subject Specific Whole Brain Mesh Generation

    Directory of Open Access Journals (Sweden)

    Chih-Yang Hsu

    2015-05-01

    Full Text Available Currently, anatomically consistent segmentation of vascular trees acquired with magnetic resonance imaging requires the use of multiple image processing steps, which, in turn, depend on manual intervention. In effect, segmentation of vascular trees from medical images is time consuming and error prone due to the tortuous geometry and weak signal in small blood vessels. To overcome errors and accelerate the image processing time, we introduce an automatic image processing pipeline for constructing subject specific computational meshes for entire cerebral vasculature, including segmentation of ancillary structures; the grey and white matter, cerebrospinal fluid space, skull, and scalp. To demonstrate the validity of the new pipeline, we segmented the entire intracranial compartment with special attention of the angioarchitecture from magnetic resonance imaging acquired for two healthy volunteers. The raw images were processed through our pipeline for automatic segmentation and mesh generation. Due to partial volume effect and finite resolution, the computational meshes intersect with each other at respective interfaces. To eliminate anatomically inconsistent overlap, we utilized morphological operations to separate the structures with a physiologically sound gap spaces. The resulting meshes exhibit anatomically correct spatial extent and relative positions without intersections. For validation, we computed critical biometrics of the angioarchitecture, the cortical surfaces, ventricular system, and cerebrospinal fluid (CSF spaces and compared against literature values. Volumina and surface areas of the computational mesh were found to be in physiological ranges. In conclusion, we present an automatic image processing pipeline to automate the segmentation of the main intracranial compartments including a subject-specific vascular trees. These computational meshes can be used in 3D immersive visualization for diagnosis, surgery planning with haptics

  15. Generating demand for pharmacist-provided medication therapy management: identifying patient-preferred marketing strategies.

    Science.gov (United States)

    Garcia, Gladys M; Snyder, Margie E; McGrath, Stephanie Harriman; Smith, Randall B; McGivney, Melissa Somma

    2009-01-01

    To identify effective strategies for marketing pharmacist-provided medication therapy management (MTM) services to patients in a self-insured employer setting. Qualitative study. University of Pittsburgh during March through May 2008. 26 university employees taking at least one chronic medication. Three focus group sessions were conducted using a semistructured topic guide to facilitate the discussion. Employees' perceived medication-related needs, perceived benefits of pharmacist-provided MTM, potential barriers for employee participation in MTM, and effective strategies for marketing MTM. Participants reported concerns with timing of doses, medication costs, access, and ensuring adherence. Participants generally felt positively toward pharmacists; however, the level of reported patient contact with pharmacists varied among participants. Some participants questioned pharmacists' education and qualifications for this enhanced role in patient care. Perceived benefits of MTM noted by participants included the opportunity to obtain personalized information about their medications and the potential for improved communication among their health providers. Barriers to patient participation were out-of-pocket costs and lack of time for MTM visits. Participants suggested use of alternative words to describe MTM and marketing approaches that involve personal contact. Pharmacists should emphasize parts of MTM that patients feel are most beneficial (i.e., provision of a personal medication record) and use patient-friendly language to describe MTM when marketing their practice. Patients will need greater exposure to the concept of MTM and the pharmacists' role in order to correctly describe and assign value to this type of pharmacist patient care practice.

  16. On two-particle correlations of identical pions

    International Nuclear Information System (INIS)

    Podgoretskij, M.I.

    1991-01-01

    The pion generation processes, in which the interference term describing the correlations of identical pions seems to be negative, have been analyzed. It is shown that similar processes can take place, in particular, in nuclear collisions at intermediate energies

  17. Real and virtual pions in nuclei

    International Nuclear Information System (INIS)

    Giraud, N.

    1984-02-01

    The thesis first part is concerned with physical pion interaction with deuton, studied in a three-body problem frame. The elastic cross-section in the energy range near the resonance (3-3), has been deduced taking in account the pion virtual absorption. The second part is concerned with virtual pion in nuclei. In particular the virtual pion cloud around the nucleus has been studied and the effective constant coupling pion-nucleus has been deduced. This one is strongly reduced by polorazation effects of the nuclear medium (essentially by virtual excitation of the Δ isobar), in relation to its value for free nucleon collection. In the frame of the same polarization model, the pion field inside the nucleus has been studied also. This field is lowered for small momentum transfer. It is increased for large momentum transfer. This last phenomenon corresponds to critical opalescence related to phase transition of pion condensation [fr

  18. Pion polarizabilities measurement at COMPASS

    CERN Document Server

    Guskov, Alexey

    2008-01-01

    The electromagnetic structure of pions is probed in $\\pi^{−} + (A,Z)\\rightarrow\\pi^{−} + (A,Z) +\\gamma$ Compton scattering in inverse kinematics (Primakoff reaction) and described by the electric $(\\bar{\\alpha_{\\pi}})$ and the magnetic $(\\bar{\\beta_{\\pi}})$ polarizabilities that depend on the rigidity of pion’s internal structure as a composite particle. Values for pion polarizabilities can be extracted from the comparison of the differential cross section for scattering of pointlike pions with the measured cross section. The pion polarizability measurement was performed with $a \\pi^{−}$ beam of 190 GeV. The high beam intensity, the good spectrometer resolution, the high rate capability, the high acceptance and the possibility to use pion and muon beams, unique to the COMPASS experiment, provide the tools to measure precisely the pion polarizabilities in the Primakoff reaction. The preliminary result for pion polarizabilities under the assumption of $\\bar{\\alpha_{\\pi}} + \\bar{\\beta_{\\pi}} =$ 0 is $\\ba...

  19. Charge-odd and single-spin effects in two pion production in ep bar collisions

    International Nuclear Information System (INIS)

    Galynskij, M.V.; Kuraev, E.A.; Shajkhatdenov, B.G.; Ratcliffe, P.G.

    2000-01-01

    We consider two-photon and Bremsstrahlung mechanisms for the production of two charged pions in high-energy electron (proton) scattering off a transversely polarised proton. Interference between the relevant amplitudes generates a charge-odd contribution to the cross section for the process. In a kinematics with a jet moving along electron spin-independent part may be used for determination of phase differences for pion-pion scattering in the states with orbital momentum 0 or 2 and 1 whereas in a kinematics with a jet moving along proton spin-dependent part may be used to explain the experimental data for single-spin correlations in the production of negatively charged pions. We also discuss the backgrounds and estimate the accuracy of the results at less than 10% level. In addition simplified formulae derived for specific kinematics, with small total transverse pion momentum, are given

  20. Medical irradiation in 10 episodes; L'irradiation medicale en 10 episodes

    Energy Technology Data Exchange (ETDEWEB)

    Cordoliani, Y.S. [Hopital du Val-de-Grace, Service Radiologie, 75 - Paris (France); Kalifa, G. [Hopital Saint-Vincent-de-Paul, Service Radiologie, 75 - Paris (France); Lefaure, Ch.; Lochard, J. [Centre d' Etude sur l' Evaluation de la Protection dans le domaine Nucleaire, 92 - Fontenay-aux-Roses (France)

    2000-07-01

    Illustrated by strip cartoons, this publication recalls the historical development in the field of X rays and their medical use, explains the risks associated with the use of radioactive rays and therefore that a the use of a radiography is not always required. It indicates and comments the share of medical irradiation in the whole radioactive exposure, and the adopted precaution principle. It outlines that risks are more important for embryos, foetuses, babies and young children, outlines the best practices in the field of radiography. It presents the various radionuclides present in the human body and their medical use or application, evokes other available techniques used to view inside the body (echography, magnetic resonance imaging), the use of radiological technical for medical purposes on healthy people and as curative means. The progress associated with the introduction of digital processing is evoked

  1. Generalized Veneziano model for pion scattering off isovector currents and the scaling limit

    CERN Document Server

    Rothe, H J; Rolhe, K D

    1972-01-01

    Starting from a local one-particle approximation scheme for the commutator of two conserved currents, the authors construct a generalized Veneziano model for pion scattering off neutral and charged isovector currents, satisfying the constraints of current conservation and current algebra. The model factorizes correctly on the leading Regge trajectories and incorporates the proper Regge behaviour for strong amplitudes. Fixed poles are found to be present in the s and t channels of the one- and two-current amplitudes. Furthermore, the model makes definite predictions about the structure of Schwinger terms and of the 'seagull' terms in the retarded commutator. (13 refs).

  2. Collins and Sivers Transverse Spin Asymmetries for Pions and Kaons on Deuterons

    CERN Document Server

    Alekseev, M.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Arbuzov, A.; Badelek, Barbara Maria; Balestra, F.; Ball, J.; Barth, J.; Baum, Guenter; Bedfer, Y.; Bernet, Colin; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, Franco; Brona, G.; Burtin, E.; Bussa, M.P.; Chapiro, A.; Chiosso, M.; Cicuttin, A.; Colantoni, M.; Crespo, M.L.; Dalla Torre, S.; Dafni, T.; Das, S.; Dasgupta, S.S.; De Masi, R.; Dedek, N.; Dhara, L.; Diaz, V.; Dinkelbach, A.M.; Donskov, S.V.; Dorofeev, V.A.; Doshita, N.; Duic, V.; Dunnweber, W.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Falaleev, V.; Ferrero, L.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; Franz, J.; Friedrich, J.M.; Garfagnini, R.; Gautheron, Fabrice; Gavrichtchouk, O.P.; Gazda, R.; Geyer, R.; Giorgi, M.; Gobbo, Benigno; Gorin, A.M.; Grabmuller, S.; Grajek, O.A.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; Hannappel, J.; von Harrach, D.; Hasegawa, T.; Heckmann, J.; Hedicke, S.; Heinsius, Fritz-Herbert; Hermann, R.; Hess, C.; Hinterberger, F.; von Hodenberg, M.; Horikawa, S.; d'Hose, N.; Ilgner, C.; Ioukaev, A.I.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Jahn, R.; Janata, A.; Jasinski, P.; Joosten, R.; Jouravlev, N.I.; Kabuss, E.; Kang, D.; Ketzer, Bernhard; Khaustov, G.V.; Khokhlov, Yu.A.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Kolosov, V.N.; Komissarov, E.V.; Kondo, K.; Konigsmann, Kay; Konstantinov, V.F.; Korentchenko, A.S.; Koutchinski, N.A.; Kral, A.; Kravchuk, N.P.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, Fabienne; Kurek, Krzysztof; Ladygin, M.E.; Le Goff, Jean-Marc; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Ludwig, I.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.Thomas; Mikhailov, Yu.V.; Moinester, M.A.; Nagaytsev, A.; Nagel, T.; Nahle, O.; Nassalski, J.; Neliba, S.; Nerling, F.; Neubert, S.; Neyret, D.P.; Nikolaenko, V.I.; Nikolaev, K.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Pagano, P.; Panebianco, S.; Panknin, R.; Panzieri, D.; Paul, S.; Pawlukiewicz-Kaminska, B.; Peshekhonov, D.V.; Peshekhonov, V.D.; Piragino, G.; Platchkov, Stephane; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Procureur, S.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Reggiani, D.; Richter, A.; Robinet, F.; Rondio, Ewa; Rozhdestvensky, A.M.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, Igor A.; Schiavon, P.; Schill, Christian; Schonmeier, P.; Schroder, W.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stinzing, F.; Sugonyaev, V.P.; Sulc, M.; Sulej, R.; Takabayashi, N.; Tchalishev, V.V.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Venugopal, G.; Virius, M.; Vlassov, N.V.; Vossen, A.; Webb, Robert C.; Weitzel, Q.; Windmolders, R.; Wirth, S.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziegler, R.; Zvyagin, A.

    2009-01-01

    The measurements of the Collins and Sivers asymmetries of identified hadrons produced in deep-inelastic scattering of 160 GeV/c muons on a transversely polarised 6LiD target at COMPASS are presented. The results for charged pions and charged and neutral kaons correspond to all data available, which were collected from 2002 to 2004. For all final state particles both the Collins and Sivers asymmetries turn out to be small, compatible with zero within the statistical errors, in line with the previously published results for not identified charged hadrons, and with the expected cancellation between the u- and d-quark contributions.

  3. Dosimetry for Crystals Irradiation

    CERN Document Server

    Lecomte, Pierre

    2005-01-01

    Before shipment to CMS, all PbWO4 crystals produced in China are irradiated there with 60 Co , in order to insure that the induced absorption coefficient is within specifications. Acceptance tests at CERNand at ENEA also include irradiation with gamma rays from 60 Co sources. There were initially discrepancies in quoted doses and doserates as well as in induced absorption coefficients. The present work resolves the discrepancies in irradiation measurements and defines common dosimetry methods for consistency checks between irradiation facilities.

  4. Large-angle theory for pion-nucleus scattering at high energies

    International Nuclear Information System (INIS)

    Hoock, D.W. Jr.

    1978-01-01

    An approximate solution for high-energy, projectile-nucleus, multiple scattering is developed from the exact Watson series and applied to pion scattering for 12 C and 4 He. Agreement with measured differential cross sections available from the literature for the range 150 to 260 MeV pion laboratory energies is surprisingly good. The approximation method expands the propagators of the Watson series about the transverse component of the momentum transfer. Contributions of each of the first two terms to double scattering from a Gaussian potential are compared to the exact solution. The purely plane-wave propagation produces a scattering amplitude that agrees to order (k 0 a) -1 with the exact solution at the forward and backward directions at high energies. The second (off-axis) propagation term produces an amplitude that is one order smaller at forward angles and two orders smaller at 180 0 than the exact amplitude. At intermediate angles it is of the same order. The general multiple-scattering series is approximated with selection of plane-wave propagation as the fundamental process at large and small angles. This model suggests that a single nucleon accepts most of the momentum transfer for backward scattering. The resulting multiple-scattering formula agrees with the well-known high-energy eikonal theory at small angles and the backward-angle scattering formula of Chen at exactly 180 0 . A lowest-order formula that includes off-axis propagation is also derived. Predicted differential cross sections are found to be sensitive to nucleon motion and binding. For 4 He the effect of the nuclear potential on the pion kinetic energy is also examined and found to produce significant changes in the predicted cross sections

  5. Physics of the pion liquid

    International Nuclear Information System (INIS)

    Shuryak, E.V.

    1990-01-01

    Excited hadronic matter in the temperature interval T = 100-200 MeV is not an ideal pion gas, but ratehr a liquid, in which attractive interaction among particles plays an important role. Pion dispersion curve is in this case essentially modified by a kind of collective momentum-dependent potential, which becomes important as the quasipion comes to the boundary of the system. The author shows that these effects can provide an explanation for a number of recent experimental puzzles, in particular, for the observed copious production of soft pions and soft photons in high energy hadronic reactions

  6. Physics of the pion liquid

    International Nuclear Information System (INIS)

    Shuryak, E.V.

    1990-04-01

    Excited hadronic matter in the temperature interval T = 100--200 MeV is not an ideal pion gas, but rather a liquid, in which attractive interaction among particles plays an important role. Pion dispersion curve is in this case essentially modified by a kind of collective momentum-dependent potential, which becomes important as the ''quasipion'' comes to the boundary of the system. We show that effects can provide and explanation for a number of recent experimental puzzles, in particular, for the observed copious production of soft pions and soft photons in high energy hadronic reactions. 31 refs., 13 figs

  7. Chiral Dynamics in Pion-Photon Reactions Habilitation

    CERN Document Server

    Friedrich, Jan Michael

    As the lightest particle of the strong force, the pion plays a central role in the field of strong interactions, and understanding its properties is of prime relevance for understanding the strong interaction in general. The low-energy behaviour of pions is of particular interest. Although the quark-gluon substructure and their quantum chromodynamics is not apparent then, this specific inner structure causes the presence of approximate symmetries in pion-pion interactions and in pion decays, which gives rise to the systematic description of processes involving pions in terms of few low-energy constants. Specifically, the chiral symmetry and its spontaneous and explicit breaking, treated in chiral perturbation theory (ChPT), leads to firm predictions for low-energy properties of the pion. To those belong the electromagnetic polarisabilities of the pion, describing the leading-order structure effect in pion Compton scattering. The research presented in this work is concerned with the interaction of pions and ph...

  8. New irradiation facilities at the Australian national medical cyclotron

    International Nuclear Information System (INIS)

    Parcell, S.K.; Arnott, D.W.; Conard, E.M.

    1999-01-01

    Two new irradiation facilities have been developed at the National Medical Cyclotron for radionuclide production. The first relocates PET irradiations from the cyclotron vault to a dedicated PET beam room, to improve accessibility and reduce radiation exposures associated with target maintenance. This new facility consists of a beam line to transport 16-30 MeV proton beams from the cyclotron to 1 of 8 PET targets mounted on a target rack. The target rack has increased the number of targets available for production and experimentation. The second is a completely independent solid target irradiation facility for SPECT. This facility consists of a beam line to transport 26-30 MeV proton beams from the cyclotron to a dedicated beam room containing one solid target station. A new pneumatic target transfer system was also developed to transport the solid target to and from the existing chemistry hot cells. The beam line and target components are operated under the control of a dedicated PLC with a PC based user interface. The development and some technical aspects of these new irradiation facilities are discussed here. (author)

  9. Pions in the nuclear medium

    International Nuclear Information System (INIS)

    Chanfray, G.

    1996-07-01

    We discuss various aspects of pion physics in the nuclear medium. We first study s-wave pion-nucleus interaction in connection with chiral symmetry restoration and quark condensate in the nuclear medium. We then address the question of p-wave pion-nucleus interaction and collective pionic modes in nuclei and draw the consequences for in medium ππ correlations especially in the scalar-isoscalar channel. We finally discuss the modification of the rho meson mass spectrum at finite density and/or temperature in connection with relativistic heavy ion collisions

  10. Order of 24 April 1970 on the setting up of ionizing radiation electric generators for medical purposes

    International Nuclear Information System (INIS)

    1970-01-01

    This Order prescribes that the setting up of electric generators emitting ionizing radiations with an energy higher than 500 KeV used for medical purposes are subject to licensing and provides a model applications form to this effect. (NEA) [fr

  11. Impact of problem-based, active learning on graduation rates for 10 generations of Dutch medical students

    NARCIS (Netherlands)

    Schmidt, Henk G.; Cohen-Schotanus, Janke; Arends, Lidia R.

    We aimed to study the effects of active-learning curricula on graduation rates of students and on the length of time needed to graduate. Graduation rates for 10 generations of students enrolling in the eight Dutch medical schools between 1989 and 1998 were analysed. In addition, time needed to

  12. The effect of helium generation and irradiation temperature on tritium release from neutron irradiated beryllium

    International Nuclear Information System (INIS)

    Kupriyanov, I.B.; Gorokhov, V.A.; Vlasov, V.V.; Kovalev, A.M.; Chakin, V.P.

    2004-01-01

    The effect of neutron irradiation condition on tritium release from beryllium is described in this paper. Beryllium samples were irradiated in the SM reactor with neutron fluence (E > 0.1 MeV) of (0.37-2.0) x 10 22 cm -2 at 70-100degC and 650-700degC. Mass-spectrometer technique was used in out of tritium release experiments during stepped-temperature anneal within a temperature range from 250 to 1300degC. The total amount of helium accumulated in irradiated beryllium samples varied from 521 appm to 3061 appm. The first signs of tritium release were detected at temperature of 406-553degC. It was shown that irradiation temperature and helium generation level significantly affect the tritium release. A fraction of 44 - 74 % of tritium content in samples irradiated at low temperature (70 - 100degC) is release from beryllium at an annealing temperature below 800degC, whereas for samples after high temperature irradiation (650 - 700 degC) tritium release did not exceed 14 %. Majority of tritium (∼68%) is released within a temperature range from 800 to 920 degC. The increase of helium generation from 521 appm to 3061 appm results in lowering the temperature of maximal tritium release rate and the upper temperature of tritium release from beryllium by 100-130degC and 200-240degC, correspondingly. On the basis of data obtained, the diffusion coefficients of tritium in beryllium were calculated. (author)

  13. Modeling and analysis of all the positron emitters simulation steps generated during the treatment phase in proton-therapy - from the beam to the PET camera - for the follow-up of the irradiations

    International Nuclear Information System (INIS)

    Ty, C.V.N.

    2012-01-01

    The proton-therapy is an innovative technique for cancer treatment in critical areas, such as the eye or the head. Even though the interaction of protons with human tissues is a well-known physical phenomenon which gives rise to the proton-therapy, there are uncertainties on the proton trajectory due to heterogeneities in the irradiated tissue, the calculation of the beam parameters in the planning treatment affects the theoretical benefits of the protons and the chosen dose delivery process. Thus, methods for irradiation quality control have been suggested. Most of them rely on utilizing the mapping of the positron emitters generated during the irradiation. They are detectable and quantifiable thanks to the use of the PET (positron emitter tomography), a medical imaging technique mainly used for the cancer expansion assessment. PET acquisitions were proposed and then realized on phantoms and patients after proton-therapy. The quality control relies on comparing the measured radioactive distribution to the simulated β + distribution. The modeling of the positron activity generated by protons in the irradiated area can be divided into three steps: the simulation of the proton beam, the modeling of the proton interactions in the irradiated object and the modeling of the PET acquisition. Different ways of simulating these steps are possible. This PhD work suggests different ways of modeling the three steps and evaluates theirs benefits for the irradiation quality control. We have restrained our evaluation to the verification of the proton range and to the uncertainties related to the proton range. This research work utilizes on irradiations in homogenous and inhomogeneous areas in a head model. We have compared the uncertainties on the proton range measured thanks to the following β + distributions: 1) A β + distribution obtained by modeling the irradiation with a proton beam simulated analytically and simulated using the complete Monte Carlo method; 2) A Monte

  14. Public understanding for medical radiation

    International Nuclear Information System (INIS)

    Yoo, Seongyeol

    1994-01-01

    Main sources of radiation exposure are radiography for the diagnosis of disease and radiation therapy to kill cancer cells, which are using X-ray generators or radioisotopes. The radiation of medical purpose irradiates intentionally to the patients. Another example of intentional exposure is occupational workers who are handling radiological equipment. The patients receive radiation more than the dose exposed to the occupational workers, but there is no doubt for the secondary radiation hazard. Although the epidemiologic studies represents that even low dose irradiation can cause epidemiologic studies represents that even low dose irradiation can cause cancer or congenital anomaly in human as a late effect, the risk is negligible, particularly when it is compared with the incidence of same disease in general population

  15. Connected and disconnected contractions in pion-pion scattering

    Science.gov (United States)

    Acharya, Neramballi Ripunjay; Guo, Feng-Kun; Meißner, Ulf-G.; Seng, Chien-Yeah

    2017-09-01

    We show that the interplay of chiral effective field theory and lattice QCD can be used in the evaluation of so-called disconnected diagrams, which appear in the study of the isoscalar and isovector channels of pion-pion scattering and have long been a major challenge for the lattice community. By means of partially-quenched chiral perturbation theory, we distinguish and analyze the effects from different types of contraction diagrams to the pion-pion scattering amplitude, including its scattering lengths and the energy-dependence of its imaginary part. Our results may be used to test the current degree of accuracy of lattice calculation in the handling of disconnected diagrams, as well as to set criteria for the future improvement of relevant lattice computational techniques that may play a critical role in the study of other interesting QCD matrix elements.

  16. Separable-potential model for the pion--nucleon interaction

    International Nuclear Information System (INIS)

    Nutt, W.T.

    1976-01-01

    A separable potential which fits the low and intermediate π-N scattering is proposed which is more convenient for application than those separable models which use Regge parameterizations of the very high energy phase shifts. The form factors for this model are equal to zero for momenta q greater than 1 GeV/c, and are expected to provide more reasonable off-shell behavior than the form factors obtained from those models based on the Regge extrapolation

  17. Light cone sum rules for single-pion electroproduction

    International Nuclear Information System (INIS)

    Mallik, S.

    1978-01-01

    Light cone dispersion sum rules (of low energy and superconvergence types) are derived for nucleon matrix elements of the commutator involving electromagnetic and divergence of axial vector currents. The superconvergence type sum rules in the fixed mass limit are rewritten without requiring the knowledge of Regge subtractions. The retarded scaling functions occurring in these sum rules are evaluated within the framework of quark light cone algebra of currents. Besides a general consistency check of the framework underlying the derivation, the author infers, on the basis of crude evaluation of scaling functions, an upper limit of 100 MeV for the bare mass of nonstrange quarks. (Auth.)

  18. Anisotropy function for pion-proton elastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Saleem, Mohammad; Fazal-e-Aleem; Rashid, Haris

    1988-09-01

    By using the generalised Chou-Yang model and the experimental data on ..pi../sup -/p elastic scattering at 200 GeV/c, the anisotropy function which reflects the non-isotropic nature of elastic scattering is computed for the reaction ..pi../sup -/p -> ..pi../sup -/p.

  19. Anisotropy function for pion-proton elastic scattering

    International Nuclear Information System (INIS)

    Saleem, Mohammad; Fazal-e-Aleem; Rashid, Haris

    1988-01-01

    By using the generalised Chou-Yang model and the experimental data on π - p elastic scattering at 200 GeV/c, the anisotropy function which reflects the non-isotropic nature of elastic scattering is computed for the reaction π - p → π - p. (author)

  20. First search for exotic Z Boson decays into photons and neutral pions in hadron collisions.

    Science.gov (United States)

    Aaltonen, T; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Bae, T; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brigliadori, L; Bromberg, C; Brucken, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Butti, P; Buzatu, A; Calamba, A; Camarda, S; Campanelli, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Cho, K; Chokheli, D; Clark, A; Clarke, C; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Cremonesi, M; Cruz, D; Cuevas, J; Culbertson, R; d'Ascenzo, N; Datta, M; de Barbaro, P; Demortier, L; Deninno, M; D'Errico, M; Devoto, F; Di Canto, A; Di Ruzza, B; Dittmann, J R; Donati, S; D'Onofrio, M; Dorigo, M; Driutti, A; Ebina, K; Edgar, R; Elagin, A; Erbacher, R; Errede, S; Esham, B; Farrington, S; Fernández Ramos, J P; Field, R; Flanagan, G; Forrest, R; Franklin, M; Freeman, J C; Frisch, H; Funakoshi, Y; Galloni, C; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González López, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gramellini, E; Grinstein, S; Grosso-Pilcher, C; Group, R C; Guimaraes da Costa, J; Hahn, S R; Han, J Y; Happacher, F; Hara, K; Hare, M; Harr, R F; Harrington-Taber, T; Hatakeyama, K; Hays, C; Heinrich, J; Herndon, M; Hocker, A; Hong, Z; Hopkins, W; Hou, S; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kambeitz, M; Kamon, T; Karchin, P E; Kasmi, A; Kato, Y; Ketchum, W; Keung, J; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S H; Kim, S B; Kim, Y J; Kim, Y K; Kimura, N; Kirby, M; Knoepfel, K; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Kruse, M; Kuhr, T; Kurata, M; Laasanen, A T; Lammel, S; Lancaster, M; Lannon, K; Latino, G; Lee, H S; Lee, J S; Leo, S; Leone, S; Lewis, J D; Limosani, A; Lipeles, E; Lister, A; Liu, H; Liu, Q; Liu, T; Lockwitz, S; Loginov, A; Lucchesi, D; Lucà, A; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maestro, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Marchese, L; Margaroli, F; Marino, P; Martínez, M; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McNulty, R; Mehta, A; Mehtala, P; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M J; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Nigmanov, T; Nodulman, L; Noh, S Y; Norniella, O; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagliarone, C; Palencia, E; Palni, P; Papadimitriou, V; Parker, W; Pauletta, G; Paulini, M; Paus, C; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Poprocki, S; Potamianos, K; Pranko, A; Prokoshin, F; Ptohos, F; Punzi, G; Ranjan, N; Redondo Fernández, I; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodriguez, T; Rolli, S; Ronzani, M; Roser, R; Rosner, J L; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Sakumoto, W K; Sakurai, Y; Santi, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schwarz, T; Scodellaro, L; Scuri, F; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shreyber-Tecker, I; Simonenko, A; Sliwa, K; Smith, J R; Snider, F D; Song, H; Sorin, V; St Denis, R; Stancari, M; Stentz, D; Strologas, J; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thomson, E; Thukral, V; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Ukegawa, F; Uozumi, S; Vázquez, F; Velev, G; Vellidis, C; Vernieri, C; Vidal, M; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wallny, R; Wang, S M; Waters, D; Wester Iii, W C; Whiteson, D; Wicklund, A B; Wilbur, S; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamato, D; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Zanetti, A M; Zeng, Y; Zhou, C; Zucchelli, S

    2014-03-21

    A search for forbidden and exotic Z boson decays in the diphoton mass spectrum is presented for the first time in hadron collisions, based on data corresponding to 10.0 fb(-1) of integrated luminosity from proton-antiproton collisions at √s = 1.96 TeV collected by the CDF experiment. No evidence of signal is observed, and 95% credibility level Bayesian upper limits are set on the branching ratios of decays of the Z boson to a photon and neutral pion (which is detected as a photon), a pair of photons, and a pair of neutral pions. The observed branching ratio limits are 2.01 × 10(-5) for Z → π(0)γ, 1.46 × 10(-5) for Z → γγ, and 1.52 × 10(-5) for Z → π(0)π(0). The Z → π(0)γ and Z → γγ limits improve the most stringent results from other experiments by factors of 2.6 and 3.6, respectively. The Z → π(0)π(0) branching ratio limit is the first experimental result on this decay.

  1. Direct determination of two-pion correlations for $\\overline{p}p \\to 2\\pi^{+}2\\pi^{-}$ annihilation at rest

    CERN Document Server

    Angelopoulos, Angelos; Aslanides, Elie; Backenstoss, Gerhard; Bargassa, P; Behnke, O; Benelli, A; Bertin, V; Blanc, F; Bloch, P; Carlson, P J; Carroll, M; Carvalho, J; Cawley, E; Charalambous, S; Chardin, G; Chertok, M B; Cody, A; Danielsson, M; Dejardin, M; Derré, J; Ealet, A; Eleftheriadis, C; Evangelou, I; Faravel, L; Ferreira-Marques, R; Fetscher, W; Fidecaro, Maria; Filipcic, A; Francis, D; Fry, J; Gabathuler, Erwin; Gamet, R; Garreta, D; Gerber, H J; Go, A; Haselden, A; Hayman, P J; Henry-Coüannier, F; Hollander, R W; Hubert, E; Jon-And, K; Kettle, P R; Kokkas, P; Kreuger, R; Le Gac, R; Leimgruber, F; Liolios, A; Machado, E; Mandic, I; Manthos, N; Marel, Gérard; Mikuz, M; Miller, J; Montanet, François; Müller, A; Nakada, Tatsuya; Pagels, B; Papadopoulos, I M; Pavlopoulos, P; Pinto da Cunha, J; Policarpo, Armando; Polivka, G; Rickenbach, R; Roberts, B L; Ruf, T; Sakelliou, L; Sanders, P; Schäfer, M; Schaller, L A; Schietinger, T; Schopper, A; Soares, A; Tauscher, Ludwig; Thibault, C; Touchard, F; Touramanis, C; Triantis, F A; Van Beveren, E; van Eijk, C W E; Vlachos, S; Weber, P; Wigger, O; Wolter, M; Yéche, C; Zavrtanik, D; Zimmerman, D; Locher, M P; Markushin, V E

    1998-01-01

    We study $\\pi\\pi$ correlations in the exclusive reaction $\\ppb \\to 2\\pi^+2\\pi^-$ at rest measured by the CPLEAR experiment. Avoiding the introduction of an arbitrary reference sample, we analyse differential distributions for equal charge pion pairs removing the phase-space factor event by event. A peak at small relative momenta is most pronounced for large total momentum of the pair. The physical implications of bosonic symmetrization for the properties of the pion source, in particular its radius, are briefly discussed. The two extremes considered are the chaotic Hanbury-Brown--Twiss mechanism and the coherent Skyrmion model.

  2. Visual sensations induced by relativistic pions

    International Nuclear Information System (INIS)

    McNulty, P.J.; Pease, V.P.; Bond, V.P.

    1976-01-01

    Visual sensations were experienced when bursts of high-energy pions passed through the dark-adapted right eyes of three human subjects. The threshold for a visual sensation was typically 1 to 3 μrad at the retina. Data are presented to show that the mechanism is Cerenkov radiation generated within the vitreous humor. Threshold measurements agree with published optical data. A comparison is made between our observations and the light flashes observed in deep space by Apollo astronauts

  3. PLUTON: Three-group neutronic code for burnup analysis of isotope generation and depletion in highly irradiated LWR fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Lemehov, Sergei E; Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-08-01

    PLUTON is a three-group neutronic code analyzing, as functions of time and burnup, the change of radial profiles, together with average values, of power density, burnup, concentration of trans-uranium elements, plutonium buildup, depletion of fissile elements, and fission product generation in water reactor fuel rod with standard UO{sub 2}, UO{sub 2}-Gd{sub 2}O{sub 3}, inhomogeneous MOX, and UO{sub 2}-ThO{sub 2}. The PLUTON code, which has been designed to be run on Windows PC, has adopted a theoretical shape function of neutron attenuation in pellet, which enables users to perform a very fast and accurate calculation easily. The present code includes the irradiation conditions of the Halden Reactor which gives verification data for the code. The total list of trans-uranium elements included in the calculations consists of {sub 92}U{sup 233-239}, {sub 93}Np{sup 237-239}, {sub 94}Pu{sup 238-243}, {sub 95}Am{sup 241-244} (including isomers), and {sub 96}Cm{sup 242-245}. Poisoning fission products are represented by {sub 54}Xe{sup 131,133,135}, {sub 48}Cd{sup 113}, {sub 62}Sm{sup 149,151,152}, {sub 64}Gd{sup 154-160}, {sub 63}Eu{sup 153,155}, {sub 36}Kr{sup 83,85}, {sub 42}Mo{sup 95}, {sub 43}Tc{sup 99}, {sub 45}Rh{sup 103}, {sub 47}Ag{sup 109}, {sub 53}I{sup 127,129,131}, {sub 55}Cs{sup 133}, {sub 57}La{sup 139}, {sub 59}Pr{sup 141}, {sub 60}Nd{sup 143-150}, {sub 61}Pm{sup 147}. Fission gases and volatiles included in the code are {sub 36}Kr{sup 83-86}, {sub 54}Xe{sup 129-136}, {sub 52}Te{sup 125-130}, {sub 53}I{sup 127-131}, {sub 55}Cs{sup 133-137}, and {sub 56}Ba{sup 135-140}. Verification has been performed up to 83 GWd/tU, and a satisfactory agreement has been obtained. (author)

  4. A Study of Hadronic Calibration Schemes for Pion Test Beam Data in the ATLAS Forward Calorimeter

    CERN Document Server

    McCarthy, Thomas G

    The ATLAS forward calorimeters constitute a small though important fraction of the detector's calorimeter system, designed in part to accurately and precisely measure the energy of particles and jets of particles originating from the collisions of high-energy protons at the detector's centre. The application of hadronic weights, a practice common in high-energy calorimetry, provides a means of compensation for the fraction of energy which is deposited by particles in the detector, but which is invisible to the detector due to the nature of hadronic showers. Explored here are various schemes of extracting hadronic weights, as well as the application of such weights, based on pion data from the 2003 ATLAS forward calorimeter test beam. During the collection of test beam data, beams of both pions and electrons of known energy, ranging from 10 to 200 GeV, were fired at specific points of an isolated detector in order to understand its response. The improvement in noise-subtracted energy resolution with respect to...

  5. Pion distribution in the nucleon

    International Nuclear Information System (INIS)

    Lee, T.-S.H.

    1989-01-01

    A model is presented for calculating the pion wave function inside the nucleon. By assuming that all pions around a core of the nucleon are in the lowest eigenstate of the system, it is shown that both the bound state and πN scattering amplitude can be consistently described by an exactly soluble model defined in the subspace spanned by the core state and the physical πN state. The parameters of the model are determined by fitting the data of the nucleon mass, πNN coupling constant and low energy πN scattering phase shifts. The model predicts that the probability of finding the pion component inside the nucleon is about 20%. The calculated πNN form factor differs significantly from the conventional monopole form. The dynamical consequences of the differences are demonstrated in a calculation of electromagnetic production of pions from the nucleon and the deuteron. 7 refs., 4 figs., 1 tab

  6. ICRP Publication 84 of the ICRP. Pregnancy and medical irradiation; ICRP publication 84 de la CIPR. Grossesse et irradiation medicale

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    In this volume, the ICRP answers questions relative to medical irradiation of pregnant women, that without responses could lead to unappropriated behaviours. It gives the circumstances for a women to be irradiated, the radiation doses delivered by the radiological procedures for a diagnosis and for a therapy. The risks for the fetus and the woman are tackled, their part in the general risks of the pregnancy and the information to give to the future mother. (N.C.)

  7. A long liquid Cherenkov counter for 300 to 460 MeV/c pion beams

    International Nuclear Information System (INIS)

    Zavrtanik, D.; Sever, F.; Plesko, M.; Music, M.; Kernel, G.

    1984-01-01

    A long liquid Cherenkov counter has been used to measure the proportion of muons in positive and negative pion beams in the momentum range between 300 and 460 MeV/c. A nine-parameter function fits all the spectra well. The data show a smooth dependence on incident momenta and agree with calculations of pion and muon pulse heights. (orig.)

  8. Pattern of Bone Generation after Irradiation in Vascularized Tissue Engineered Constructs.

    Science.gov (United States)

    Eweida, Ahmad; Fathi, Ibrahim; Eltawila, Ahmed M; Elsherif, Ahmad M; Elkerm, Yasser; Harhaus, Leila; Kneser, Ulrich; Sakr, Mahmoud F

    2018-02-01

     Regenerative medicine modalities provide promising alternatives to conventional reconstruction techniques but are still deficient after malignant tumor excision or irradiation due to defective vascularization.  We investigated the pattern of bone formation in axially vascularized tissue engineering constructs (AVTECs) after irradiation in a study that mimics the clinical scenario after head and neck cancer. Heterotopic bone generation was induced in a subcutaneously implanted AVTEC in the thigh of six male New Zealand rabbits. The tissue construct was made up of Nanobone (Artoss GmbH; Rostock, Germany) granules mixed with autogenous bone marrow and 80 μL of bone morphogenic protein-2 at a concentration of 1.5 μg/μL. An arteriovenous loop was created microsurgically between the saphenous vessels and implanted in the core of the construct to induce axial vascularization. The constructs were subjected to external beam irradiation on postoperative day 20 with a single dose of 15 Gy. The constructs were removed 20 days after irradiation and subjected to histological and immunohistochemical analysis for vascularization, bone formation, apoptosis, and cellular proliferation.  The vascularized constructs showed homogenous vascularization and bone formation both in their central and peripheral regions. Although vascularity, proliferation, and apoptosis were similar between central and peripheral regions of the constructs, significantly more bone was formed in the central regions of the constructs.  The study shows for the first time the pattern of bone formation in AVTECs after irradiation using doses comparable to those applied after head and neck cancer. Axial vascularization probably enhances the osteoinductive properties in the central regions of AVTECs after irradiation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Lack of appetite for food irradiation

    International Nuclear Information System (INIS)

    Tacey, Elisabeth

    1989-01-01

    The British government has approved food irradiation in Britain on a much wider scale than has taken place previously. The implications for one of the companies currently offering a gamma irradiation service are explored. Irradiation is by a large Cobalt 60 source. Currently the customers are medical, cosmetic and packaging firms. It does not yet have the facilities necessary for large-scale food irradiation, nor does it expect a huge demand for food irradiation as customer resistance is strong. However some dry spices and herbs may be treated next year. (UK)

  10. Gas-Cooled Reactor Programs annual progress report for period ending December 31, 1973. [HTGR fuel reprocessing, fuel fabrication, fuel irradiation, core materials, and fission product distribution; GCFR fuel irradiation and steam generator modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kasten, P.R.; Coobs, J.H.; Lotts, A.L.

    1976-04-01

    Progress is summarized in studies relating to HTGR fuel reprocessing, refabrication, and recycle; HTGR fuel materials development and performance testing; HTGR PCRV development; HTGR materials investigations; HTGR fuel chemistry; HTGR safety studies; and GCFR irradiation experiments and steam generator modeling.

  11. Pion Rescattering in Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Paschos, E.A. [Institute for Physics, University of Dortmund, 44221 Dortmund (Germany); Schienbein, I. [Deutsches Elektronen Synchroton (DESY), 22603 Hamburg (Germany); Yu, J.-Y. [Institute for Physics, University of Dortmund, 44221 Dortmund (Germany)

    2005-02-15

    Nuclear corrections are presented for neutrino and electron induced reactions in a pedagogical manner. The formalism is demonstrated with numerical studies and shown to produce substantial corrections in channels where the pions have the same charge with the exchanged current. Two comparisons with available data show consistency of the model. Additional experimental results along these lines will improve the accuracy of the predictions and enhance the discovery potential of experiments.

  12. Antioxidant-Conjugated Onto Gamma-Generated Chitosan Nanoparticle for Radiation Sterilized Medical Plastic

    Energy Technology Data Exchange (ETDEWEB)

    Pasaphan, W. [Department of Applied Radiation and Isotopes, Faculty of Science Kasetsart University, Bangkok (Thailand)

    2009-07-01

    The Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Bangkok, Thailand, mainly gives the course of study in the field of radiation and nuclear science and technology. The research actitivies relevant to the department are about nuclear instrument and analytical technique by nuclear methodology, radiation chemistry and processing technology, and radiation biology and agriculture. My work going on in the department is separated into two main responsibilities, i.e. (i) teaching courses and (ii) research activity. For (i), in the present time, there are 5 courses (i.e., radiation detection technique, radiation health protection, nuclear method of analysis, radioistope tracer techniques in biology and seminar) for bachelor degree and 4 courses (radiation chemistry and processing, radiation detection and dosimetry, nuclear facilities and utilization, research method in applied radiation and isotope) for master degree. In the case of (ii), my research interests head on the radiation chemistry and processing applicable to material and nanomaterial development for industrial applications, e.g. nanofilter and metal absorbent material; for medical applications, e.g. bio-additive for medical material, nanoparticle for drug delivery system, radiosensitizer for radiotherapy; for agricultural applications, e.g. pest controlled compound and plastic. The researches are also attended to biopolymer especially chitin-chiosan including functional polymer. The material for radiation dosimeter based on EPR is furthermore interesting to look for.

  13. Antioxidant-Conjugated Onto Gamma-Generated Chitosan Nanoparticle for Radiation Sterilized Medical Plastic

    International Nuclear Information System (INIS)

    Pasaphan, W.

    2009-01-01

    The Department of Applied Radiation and Isotopes, Faculty of Science, Kasetsart University, Bangkok, Thailand, mainly gives the course of study in the field of radiation and nuclear science and technology. The research actitivies relevant to the department are about nuclear instrument and analytical technique by nuclear methodology, radiation chemistry and processing technology, and radiation biology and agriculture. My work going on in the department is separated into two main responsibilities, i.e. (i) teaching courses and (ii) research activity. For (i), in the present time, there are 5 courses (i.e., radiation detection technique, radiation health protection, nuclear method of analysis, radioistope tracer techniques in biology and seminar) for bachelor degree and 4 courses (radiation chemistry and processing, radiation detection and dosimetry, nuclear facilities and utilization, research method in applied radiation and isotope) for master degree. In the case of (ii), my research interests head on the radiation chemistry and processing applicable to material and nanomaterial development for industrial applications, e.g. nanofilter and metal absorbent material; for medical applications, e.g. bio-additive for medical material, nanoparticle for drug delivery system, radiosensitizer for radiotherapy; for agricultural applications, e.g. pest controlled compound and plastic. The researches are also attended to biopolymer especially chitin-chiosan including functional polymer. The material for radiation dosimeter based on EPR is furthermore interesting to look for

  14. Determination of Relative Biological Efficacy (RBE) and Oxygen Enhancement Ratio (OER) for the entire negative and positive pion beam profile using Vicia faba roots and Drosophila embryos as biological model systems

    International Nuclear Information System (INIS)

    Baarli, J.; Bianchi, M.; Keusch, F.; Mindek, G.; Sullivan, A.H.

    As an introduction to preclinical studies, pilot studies of pion beams are planned with relatively simple biological model systems that can be quickly evaluated and that yield indicative data for further action. Inhibition of growth was studied in Vicia faba roots, a biological system excellently suited for RBE and OER studies. For comparison there are already results from a low-intensity pion irradiation. A second system used Drosophila embryos 1 and 4 hours old, which are especially well suited for LET studies. The unambiguous criterion will be failure to slip out of the oolemma. The smallness of the objects (their beam sensitivity) will make it possible to determine empirically the peak region and to determine Gain factors; furthermore, the known dependency of RBE on the development stage promises highly informative results

  15. Pion and kaon freezeout in NA44

    International Nuclear Information System (INIS)

    1994-01-01

    The NA44 spectrometer is optimized for the study of single and two-particle particle spectra near mid-rapidity for transverse momenta below ∼ 1 GeV/c. A large fraction of all pairs in the spectrometer's acceptance are at low relative momenta, resulting in small statistical uncertainties on the extracted size parameters. In addition, the spectrometer's clean particle identification allows the authors to measure correlation functions for pions, kaons, and protons. This contribution will concentrate on the source size parameters determined from pion and kaon correlation functions. These size parameters will be compared to calculations from the RQMD event generator and also interpreted in the context of a hydrodynamic model. Finally, the measured single particle spectra will be examined from the viewpoint of hydrodynamics

  16. Pion-nuclear many body problems

    International Nuclear Information System (INIS)

    Weise, W.

    1981-01-01

    This chapter examines pion-nucleus scattering data produced at the meson factories in order to gain information about the ''optical'' branches of the pion-nuclear excitation spectrum. Discusses basic meson-baryon effective Lagrangians and elementary processes; pion-baryon vertex form factors; the spin-isospin dependent baryon-baryon interaction; pions in nuclear matter; nuclear spin-isospin correlations; the baryon-hole model; photon-induced excitation of baryon-hole states; high momentum transfer properties of pion-like nuclear states; a response function for pionic low-frequency modes in finite nuclei; and applications. Finds that there is no clear evidence for pionic critical opalescence, as in agreement with the expectation that the minimal density for the appearance of a pion condensate is certainly not lower than two or three times nuclear matter density

  17. Charged-current inclusive neutrino cross sections: superscaling extension to the pion production and realistic spectral function for quasielastic region

    International Nuclear Information System (INIS)

    Ivanov, A.N.; Antonov, M.V.; Barbaro, J.A.; Caballero, G.A.; Megias, G.D.; González-Jiménez, R.; Giusti, C.; Meucci, A.; Moya de Guerra, E.; Udías, J.M.

    2015-01-01

    Superscaling approximation (SuSA) predictions to neutrino-induced charged-current pion production in the Δ-resonance region are explored under MiniBooNE experimental conditions. The results obtained within SuSA for the flux-averaged double-differential cross sections of the pion production for the ν_μ+CH_2 reaction as a function of the muon kinetic energy and of the scattering angle, the cross sections averaged over the angle, the total cross section for the pion production are compared with the corresponding MiniBooNE experimental data. The SuSA charged-current π"+ predictions are in good agreement with data on neutrino flux average cross-sections. The SuSA extension to the pion production region and the realistic spectral function S(p;ε) for quasielastic scattering are used for predictions of charged current inclusive neutrino-nucleus cross sections. The results are compared with the inclusive neutrino-nucleus data from the T2K experiment. (author)

  18. Development of Molybdenum Adsorbent for 99Mo/99mTc Radioisotope Generator Based on Irradiated Natural Molybdenum

    International Nuclear Information System (INIS)

    Rohadi Awaludin; Hotman Lubis; Sriyono; Abidin; Herlina; Endang Sarmini; Indra Saptiama; Hambali

    2011-01-01

    Preparation of 99 Mo/ 99m Tc radioisotope generator using irradiated natural molybdenum requires an adsorbent with high absorption capacity. Zirconium-based materials (ZBM), adsorbent with adsorption capacity of about 183 mg(Mo) / g(adsorbent), has been successfully synthesized. However, the adsorbent was easily broken in the Mo adsorption process due to many fractures in the grain. To increase the hardness, the material was immersed in tetraethyl orthosilicate (TEOS) and coated by TEOS flow in a column. The hardness test results showed that the ZBM with TEOS treatment was not broken when immersed into the Mo solution. Observations using SEM showed that the fractures formed on the ZBM were successfully removed by TEOS treatment. Measurements using EDS showed that after TEOS treatment, the silicon was detected and the oxygen content increased in the material surface. Adsorption test results showed that the TEOS immersion decreased the adsorption capacity of molybdenum from 183 to 79.8 mg of Mo per gram of adsorbent. The TEOS flow-in a column gave material with relatively high adsorption capacity, 140 mgMo per gram adsorbent. The content of Silicon in the surface was lower than that of adsorbent immersed in TEOS. (author)

  19. Chimera distribution amplitudes for the pion and the longitudinally polarized ρ-meson

    Energy Technology Data Exchange (ETDEWEB)

    Stefanis, N.G., E-mail: stefanis@tp2.ruhr-uni-bochum.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Pimikov, A.V., E-mail: pimikov@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna (Russian Federation); Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China)

    2016-01-15

    Using QCD sum rules with nonlocal condensates, we show that the distribution amplitude of the longitudinally polarized ρ-meson may have a shorttailed platykurtic profile in close analogy to our recently proposed platykurtic distribution amplitude for the pion. Such a chimera distribution de facto amalgamates the broad unimodal profile of the distribution amplitude, obtained with a Dyson–Schwinger equations-based computational scheme, with the suppressed tails characterizing the bimodal distribution amplitudes derived from QCD sum rules with nonlocal condensates. We argue that pattern formation, emerging from the collective synchronization of coupled oscillators, can provide a single theoretical scaffolding to study unimodal and bimodal distribution amplitudes of light mesons without recourse to particular computational schemes and the reasons for them.

  20. The pion form factor from first principles

    International Nuclear Information System (INIS)

    Heide, J. van der

    2004-01-01

    We calculate the electromagnetic form factor of the pion in quenched lattice QCD. The non-perturbatively improved Sheikoleslami-Wohlert lattice action is used together with the O(a) improved current. We calculate form factor for pion masses down to mπ = 380 MeV. We compare the mean square radius for the pion extracted from our form factors to the value obtained from the 'Bethe Salpeter amplitude'. Using (quenched) chiral perturbation theory, we extrapolate our results towards the physical pion mass

  1. Non-dipolar gauge links for transverse-momentum-dependent pion wave functions

    International Nuclear Information System (INIS)

    Wang, Y.M.

    2016-01-01

    I discuss the factorization-compatible definitions of transverse-momentum-dependent (TMD) pion wave functions which are fundamental theory inputs entering QCD factorization formulae for many hard exclusive processes. I will first demonstrate that the soft subtraction factor introduced to remove both rapidity and pinch singularities can be greatly reduced by making the maximal use of the freedom to construct the Wilson-line paths when defining the TMD wave functions. I will then turn to show that the newly proposed TMD definition with non-dipolar Wilson lines is equivalent to the one with dipolar gauge links and with a complicated soft function, to all orders of the perturbative expansion in the strong coupling, as far as the infrared behavior is concerned. (author)

  2. Photocatalyst based on titanium or iron semiconductors for the generation of hydrogen from water upon solar irradiation

    OpenAIRE

    Serra, Marco

    2016-01-01

    The objective of present thesis is to prepare and evaluate photocatalyst for hydrogen generation from water methanol mixture using solar light. This general objective has been accomplished by applying different methodology in material preparation as well as exploring the photocatalytic activity of novel semiconductors. In this way after a general introduction to the feed showing the relevance of solar fuels and in particular hydrogen generation, the...

  3. Statistical criteria for characterizing irradiance time series.

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

    2010-10-01

    We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

  4. Elastic and inelastic pion reactions on few nucleon systems

    International Nuclear Information System (INIS)

    Lensky, V.

    2007-01-01

    In the present work, we are studying elastic and inelastic pion reactions on few-body systems within the framework of chiral effective theory. We consider two specific reactions involving pions on few-nucleon systems, namely pion production in nucleon-nucleon collisions, and incoherent pion photoproduction on the deuteron. These two reactions are closely related to the issue of dispersive and absorptive corrections to the pion-deuteron scattering length, which we also consider in our analysis. The incoherent pion photoproduction is also considered as the possible source for a high-precision determination of the neutron-neutron scattering length. (orig.)

  5. Elastic and inelastic pion reactions on few nucleon systems

    Energy Technology Data Exchange (ETDEWEB)

    Lensky, V.

    2007-09-29

    In the present work, we are studying elastic and inelastic pion reactions on few-body systems within the framework of chiral effective theory. We consider two specific reactions involving pions on few-nucleon systems, namely pion production in nucleon-nucleon collisions, and incoherent pion photoproduction on the deuteron. These two reactions are closely related to the issue of dispersive and absorptive corrections to the pion-deuteron scattering length, which we also consider in our analysis. The incoherent pion photoproduction is also considered as the possible source for a high-precision determination of the neutron-neutron scattering length. (orig.)

  6. Cation-selective extraction column study for the conception of nuclear medical radionuclide generators

    International Nuclear Information System (INIS)

    Streng, Roman

    2012-01-01

    The topic of the present work is the conception of a Yttrium-90 radionuclide generator for nuclear medicine applications. Due to its physical properties Yttrium-90 is considered as one of the most useful nuclides for radiotherapeutic cancer treatment. The parent nuclide Strontium-90 is gained during reprocessing of fission products. Thus, the sustained availability of large quantities of Yttrium-90 is limited to a number of research facilities. A radionuclide generator provides an independent Yttrium-90 source and enhances the capacities for radiopharmaceutical research and biomedical applications. The present work focussed on the identification of appropriate column materials for the separation of Strontium and Yttrium. The results for two materials are reported: AnaLig registered Sr-01 and crystalline antimonic acid. Based on the mode of operation of the Technetium-99m generator the aim was to enable the construction of a compact, enclosed apparatus. The projected device comprises a reservoir for the eluant, the ion-exchange column, pipings and radiation shielding. Elution of Yttrium-90 could then be easily performed by connecting evacuated vials to the outlet tube. The prospected concept involves physical and chemical confinements that exclude most of the known processes for Strontium-Yttrium separation. For example no ligands, no oxidizing reactants (e.g. nitric acid) and no organic solvents are to be used, but small volumes of isotonic or buffer solutions and dilute acids respectively. AnaLig registered Sr-01 is a commercially available resin used in extraction chromatography. Its high selectivity for Strontium cations results from the strictly defined cavity of the imbedded cryptand. Determination of weight distribution coefficients, elution studies and pre-generator experiments were carried out. Quantitative separation of Yttrium from Strontium and Zirconium is possible using small volumes of 0,05 M hydrochloric acid as eluant. Furthermore, high flow rates

  7. Light ion linacs for medical applications

    International Nuclear Information System (INIS)

    Bradbury, J.N.; Knapp, E.A.; Nagle, D.E.

    1975-01-01

    Recent advances in linear accelerator technology point to the feasibility of designing and developing practical medical linacs for producing protons, neutrons, or π mesons for the radiation therapy of cancer. Additional uses of such linacs could include radioisotope production and charged particle radiography. For widespread utilization medical linacs must exhibit reasonable cost, compactness, reliability, and simplicity of operation. Possible extensions of current accelerator technology which might provide these characteristics are discussed in connection with linac design, fabrication techniques, materials, power sources, injectors, and particle collection and delivery systems. Parameters for a medical proton linac for producing pions are listed. (U.S.)

  8. Radiation Engineered Nanogels as Platform for Next-Generation of Medical Diagnosticsand Therapeutics

    Energy Technology Data Exchange (ETDEWEB)

    Dispenza, C.; Sabatino, M. A.; Alessi, S.; Spadaro, G., E-mail: clelia.dispenza@unipa.it [Universita degli Studi di Palermo, Dipartimento di Ingegneria Industriale, Viale delle Scienze (Parco d' Orleans), 90128 Palermo (Italy)

    2010-07-01

    Nanotechnology holds the promise of enabling new materials and systems to accomplish delicate and demanding roles in healthcare for medical diagnostics (imaging and sensing) and therapeutics (drug delivery). The development of functional nanoparticles that can ensure high MR imaging contrast and/or molecular recognition functions; or specific medical intervention at the molecular scale for treating a disease or repairing damaged tissues are currently at the agenda of many public and private research institutions and agencies. Several different nanomaterial systems have been proposed for application in nanomedicine: including colloidal systems (such as liposomes or microemulsions), quantum dots (QDs), organic and inorganic dendrimers, viral and virus-like nanoparticles, polymeric vesicles and solid lipid nanoparticles. Each of these systems has advantages and disadvantages, often related to in vivo toxic side-effects or difficult scalability of their production process at industrial level. Nanogels, or small particles formed by physically or chemically crosslinked polymer networks, represent a niche in the development of ―smart‖ nanoparticles for drug delivery and diagnostics. They offer unique advantages over other systems, including a large and flexible surface for multivalent bio-conjugation; an internal 3D aqueous environment for incorporation of large (bio)molecular drugs, the possibility to entrap active metal or mineral cores for imaging or phototherapeutic purposes; stimuli-responsiveness and biocompatibility. Moreover, conformability and flexibility make these nanoparticles able to penetrate through small pores and channels through shape modification. Major synthetic strategies for the preparation of nanogels belong to either micro-fabrication methodologies (photolithography, microfluidic, micromoulding) or to self-assembly approaches that exploit ionic, hydrophobic or covalent interactions. For the latter, in particular, dimensional control has been

  9. Radiation Engineered Nanogels as Platform for Next-Generation of Medical Diagnosticsand Therapeutics

    International Nuclear Information System (INIS)

    Dispenza, C.; Sabatino, M.A.; Alessi, S.; Spadaro, G.

    2010-01-01

    Nanotechnology holds the promise of enabling new materials and systems to accomplish delicate and demanding roles in healthcare for medical diagnostics (imaging and sensing) and therapeutics (drug delivery). The development of functional nanoparticles that can ensure high MR imaging contrast and/or molecular recognition functions; or specific medical intervention at the molecular scale for treating a disease or repairing damaged tissues are currently at the agenda of many public and private research institutions and agencies. Several different nanomaterial systems have been proposed for application in nanomedicine: including colloidal systems (such as liposomes or microemulsions), quantum dots (QDs), organic and inorganic dendrimers, viral and virus-like nanoparticles, polymeric vesicles and solid lipid nanoparticles. Each of these systems has advantages and disadvantages, often related to in vivo toxic side-effects or difficult scalability of their production process at industrial level. Nanogels, or small particles formed by physically or chemically crosslinked polymer networks, represent a niche in the development of ―smart‖ nanoparticles for drug delivery and diagnostics. They offer unique advantages over other systems, including a large and flexible surface for multivalent bio-conjugation; an internal 3D aqueous environment for incorporation of large (bio)molecular drugs, the possibility to entrap active metal or mineral cores for imaging or phototherapeutic purposes; stimuli-responsiveness and biocompatibility. Moreover, conformability and flexibility make these nanoparticles able to penetrate through small pores and channels through shape modification. Major synthetic strategies for the preparation of nanogels belong to either micro-fabrication methodologies (photolithography, microfluidic, micromoulding) or to self-assembly approaches that exploit ionic, hydrophobic or covalent interactions. For the latter, in particular, dimensional control has been

  10. NF EN ISO 11137-1, July 2006. Sterilization of health care products - Irradiation - Part 1: Requirements for development, validation and routine control of a sterilization process for medical devices; NF EN ISO 11137-1, Juillet 2006. Sterilisation des produits de sante - Irradiation - Partie 1: exigences relatives a la mise au point, a la validation et au controle de routine d'un procede de sterilisation pour les dispositifs medicaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This part of the ISO 11137 standard specifies requirements for the development, validation and routine control of a radiation sterilization process for medical devices. Although the scope of this part of the ISO 11137 standard is limited to medical devices, it specifies requirements and provides guidance that may be applicable to other products and equipment. This part of the international standard covers radiation processes employing irradiators using the radionuclide {sup 60}Co or {sup 137}Cs, a beam from an electron generator or a beam from an X-ray generator. This part of the international standard does not: - specify requirements for development, validation and routine control of a process for inactivating the causative agents of spongiform encephalopathies such as scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease; - detail specified requirements for designating a medical device as sterile; - specify a quality management system for the control of all stages of production of medical devices; - specify requirements for occupational safety associated with the design and operation of irradiation facilities; - specify requirements for the sterilization of used or reprocessed devices.

  11. Management of activated parts generated during the dismantling of linear accelerators for medical uses

    International Nuclear Information System (INIS)

    Ortiz, Teresa; Correa, Cristina

    2008-01-01

    During years 2006-2008 have been carried out to the dismantling of several linear accelerators of medical use in Spain. The two first were in the Hospital of 'La Princesa' in Madrid and in the Hospital 'Santa Creu y Sant Pau' in Barcelona. The disassembling of such was made by technicians of the providing company and of the own hospital, with the advising of experts of the Radiological Protection and Radiophysics Service of such. Technicians of the Radiological Protection Technical Unit (RPU) of ENRESA collaborated in these dismantlings with the objective to determine that pieces could be evacuated conventionally as metallic scraps and which had to be managed as radioactive waste. In the following dismantling the classification of the pieces were carried out by the technicians of the providing company. After that the technicians of the RPU of ENRESA verified this classification and characterized, in detail, the pieces classified as radioactive wasted before their removal. In this paper the activities carried out to classify the pieces and the legal bases in which it leans on, as well as the measures made for the characterization of the materials considered as radioactive waste are described. (author)

  12. Packing for food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewski, A G [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    2006-07-01

    Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)

  13. Packing for food irradiation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2006-01-01

    Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)

  14. Irradiation facilities at the Los Alamos Meson Physics Facility

    International Nuclear Information System (INIS)

    Sandberg, V.

    1990-01-01

    The irradiation facilities for testing SSC components and detector systems are described. Very high intensity proton, neutron, and pion fluxes are available with beam kinetic energies of up to 800 MeV. 4 refs., 12 figs., 2 tabs

  15. Procedural wound geometry and blood flow generation for medical training simulators

    Science.gov (United States)

    Aras, Rifat; Shen, Yuzhong; Li, Jiang

    2012-02-01

    Efficient application of wound treatment procedures is vital in both emergency room and battle zone scenes. In order to train first responders for such situations, physical casualty simulation kits, which are composed of tens of individual items, are commonly used. Similar to any other training scenarios, computer simulations can be effective means for wound treatment training purposes. For immersive and high fidelity virtual reality applications, realistic 3D models are key components. However, creation of such models is a labor intensive process. In this paper, we propose a procedural wound geometry generation technique that parameterizes key simulation inputs to establish the variability of the training scenarios without the need of labor intensive remodeling of the 3D geometry. The procedural techniques described in this work are entirely handled by the graphics processing unit (GPU) to enable interactive real-time operation of the simulation and to relieve the CPU for other computational tasks. The visible human dataset is processed and used as a volumetric texture for the internal visualization of the wound geometry. To further enhance the fidelity of the simulation, we also employ a surface flow model for blood visualization. This model is realized as a dynamic texture that is composed of a height field and a normal map and animated at each simulation step on the GPU. The procedural wound geometry and the blood flow model are applied to a thigh model and the efficiency of the technique is demonstrated in a virtual surgery scene.

  16. Biomedical applications of pion-producing accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, L [Los Alamos Scientific Lab., NM (USA)

    1980-01-01

    It was proved by the Los Alamos Scientific Laboratory of the U. S. that applications of pi-mesons in the treatment of cancer could eliminate the problem of dose localization attendant upon conventional radiation therapy. A negative pi-meson, once it is produced from energy, behaves quantum mechanically like an electron and executes orbits around a nucleus. Because its mass is 300 times that of an electron, the orbits are smaller in that ratio. Hence, on achieving the innermost orbit, the pi-meson is captured by the nucleus and causes it to explode. The resultant nuclear shrapnel travel very short distances, about 1 mm on the average, and are very effective in rendering afflicted cells non-productive without causing any damages to healthy cells in the vicinity of the tumor. Given pion therapy, over 100 patients showed encouraging results. The laboratory, sponsored by the National Cancer Institute, is now developing a small facility for pion therapy. Tests on the critical components of the pion generator are expected to be conducted within the next 12 - 16 months.

  17. On the study of proton-irradiated Tellurium targets relevant for production of medical radioisotopes 123I and 124I

    International Nuclear Information System (INIS)

    Imam Kambali; Hari Suryanto; Daya Agung Sarwono; Cahyana Amiruddin

    2014-01-01

    The energy loss distribution and range of energetic proton beams in tellurium (Te) target have been simulated using the Stopping and Range of Ion in Matter (SRIM 2013) codes. The calculated data of the proton's range were then used to determine the optimum thickness of Te targets for future production of 123 I and 124 I from 123 Te(p,n) 123 I, 124 Te(p,n) 124 I and 124 Te(p,2n) 123 I nuclear reactions using the BATAN's Cs-30 cyclotron. It was found that for an incidence angle of 0° with respect to the target normal, the optimum thickness of 123 Te and 124 Te targets for 123 I production should be 644 µm and 1.8 mm respectively, whereas a 649 µm thick 124 Te target would be Required for 124 I production. In addition, the thickness should be decreased with increasing incidence angle. The EOB yield could theoretically reach up to 13.62 Ci of 123 I at proton energy of 22 Me V and beam current of 30 µA if the 124 Te is irradiated over a period of 3 hours. The theoretical EOB yield is comparable to the experimental data with accuracy within 10%. (author)

  18. Characteristics of Patient-Centered Medical Home Initiatives that Generated Savings for Medicare: a Qualitative Multi-Case Analysis.

    Science.gov (United States)

    Burton, Rachel A; Lallemand, Nicole M; Peters, Rebecca A; Zuckerman, Stephen

    2018-02-05

    Through the Multi-Payer Advanced Primary Care Practice (MAPCP) Demonstration, Medicare, Medicaid, and private payers offered supplemental payments to 849 primary care practices that became patient-centered medical homes (PCMHs) in eight states; practices also received technical assistance and data reports. Average Medicare payments were capped at $10 per beneficiary per month in each state. Since there was variation in the eight participating states' demonstration designs, experiences, and outcomes, we conducted a qualitative multi-case analysis to identify the key factors that differentiated states that were estimated to have generated net savings for Medicare from states that did not. States' MAPCP Demonstration initiatives were comprehensively profiled in case studies based on secondary document review, three rounds of annual interviews with state staff, payers, practices, and other stakeholders, and other data sources. Case study findings were summarized in a case-ordered predictor-outcome matrix, which identified the presence or absence of key demonstration design features and experiences and arrayed states based on the amount of net savings or losses they generated for Medicare. We then used this matrix to identify initiative features that were present in at least three of the four states that generated net savings and absent from at least three of the four states that did not generate savings. A majority of the states that generated net savings: required practices to be recognized PCMHs to enter the demonstration, did not allow late entrants into the demonstration, used a consistent demonstration payment model across participating payers, and offered practices opportunities to earn performance bonuses. Practices in states that generated net savings also tended to report receiving the demonstration payments and bonuses they expected to receive, without any issues. Designers of future PCMH initiatives may increase their likelihood of generating net savings by

  19. Super ODS steels R and D for fuel cladding on next generation nuclear systems. 8) Ion irradiation effects at elevated temperatures

    International Nuclear Information System (INIS)

    Kishimoto, Hirotatsu; Kasada, Ryuta; Kimura, Akihiko; Inoue, Masaki; Okuda, Takanari; Abe, Fujio; Ohnuki, Somei; Fujisawa, Toshiharu

    2009-01-01

    The Super ODS steels, having excellent high-temperature strength and highly corrosion resistant, are considered to increase the energy efficiency by higher temperature operation and extend the lifetime of next generation nuclear systems. High-temperature strength of the ODS steels strongly depends on the dispersion of oxide particles, therefore, the irradiation effect on the dispersed oxides is critical in the material development. In the present research, ion irradiation experiments were employed to investigate microstructural stability under the irradiation environment at elevated temperatures. Ion irradiation experiments were performed with 6.4 MeV Fe ions irradiated at 650degC up to a nominal displacement damage of 60 dpa. Microstructural investigation was carried out using TEM and EDX. No significant change of grains and grain boundaries was observed by TEM investigation after the ion irradiation. Main oxide particles in the 16Cr-4Al-0.1Ti (SOC-1) ODS steel were (Y, Al) complex oxides. (Y, Ti) complex oxides were in 16Cr-0.1Ti (SOC-5) and 15.5Cr-2W-0.1Ti (SOCP-3). (Y, Zr) complex oxides were in 15.5Cr-4Al-0.6Zr (SOCP-1). No significant modification of these complex oxides was detected after the ion irradiation up to 60 dpa at 650degC. The stable complex oxides are considered to keep highly microstructural stability of the Super ODS steels under the irradiation environments. (author)

  20. Medical irradiation of children. Beware of too fast conclusion; Irradiation medicale de l'enfant. Attention aux conclusions hatives

    Energy Technology Data Exchange (ETDEWEB)

    Brisse, H. [Institut Curie, Dept. d' Imagerie, 75 - Paris (France); Sirinelli, D. [Hopital Clocheville, Service de Radiologie et Echographie, 37 - Tours (France); Adamsbaum, C. [Hopital Saint-Vincent-de-Paul, Service de Radiologie, 75 - Paris (France); Chateil, J.F. [Hopital Pellegrin, Unite de Radiopediatrie, 33 - Bordeaux (France); Claudon, M. [Centre Hospitalier Universitaire Nancy-Hopital Brabois Enfants, Service de Radiologie, 54 - Vandoeuvre-les-Nancy (France); Geoffray, A. [Fondation Lenval, Service de Radiologie, 06 - Nice (France); Petit, P. [Hopital de la Timone, Service de Radiologie, 13 - Marseille (France); Rausin, L. [Centre Hospitalier Regional de la Citadelle, Service de Radiologie, Liege (Belgium); Panuel, M. [Hopital Nord, Service de Radiologie, 13 - Marseille (France)

    2004-10-01

    The publication in january 2004 in the British medical journal of the article of P. Hall and coll. 'Effect of low doses of ionizing irradiation in infancy on cognitive function in adulthood: Swedish population based cohort study, has been noticed by the Radiation protection group of the French speaking society of pediatrics imaging. The authors evaluate the psycho-motor development of less eighteen months years old children and irradiated between 1930 and 1959 for a face angioma. They study for each dose of irradiation ( from 0 to 250 m Gy) the level of school attendance and their results to the psycho-motor tests made during conscription medical examination. They noticed a diminution of 50% of the access success rate to university for the children having received an irradiation dose of 250 mG. No effect is noticed under the irradiation dose of 100 mGy. In their conclusions the authors compare these irradiation doses to these ones delivered in brain scanner examination. These results seem overestimated compared with the work made on fetuses ( publication 84 of ICRP) then the fetus is considered as more sensitive to ionizing radiations than the infant. The dose of 120 mGy is found in the literature and now the dose delivered in pediatrics are in the area of 0 and 100 mGy where no effect has been revealed in the cohort of irradiated children. The article does not include the principle of justification that is used nowadays and the replacement by the trans fontanel echography has allowed to reduce the number of brain scanner, used only for limited cases where the benefit is superior the the risk of irradiation. (N.C.)

  1. Irradiation facilities for the production of radioisotopes for medical purposes and for industry at the Rossendorf Research Reactor

    International Nuclear Information System (INIS)

    Hieronymus, W.

    2007-01-01

    In 1955, the Government of the German Democratic Republic initiated radioisotope production. With that decision, the following plants received their go ahead: - Research reactor with its user facilities; - Cyclotron with its specific facilities; - Institute for radiochemistry; - Library, lecture hall, workshops and administration buildings supporting the necessary scientific and administrative environment. The Zentralinstitut fuer Kerntechnik (ZfK), also known as the Central Institute for Nuclear Technology, was founded at Rossendorf near Dresden, Germany, to house all those plants. The Rossendorf Research Reactor (RFR) was constructed in 1956-1957. That endeavour was enabled by the technological support of the former USSR under a bilateral agreement which included the delivery of a 2 MW research reactor of the WWR-S design

  2. Pion structure from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Javadi Motaghi, Narjes

    2015-05-12

    In this thesis we use lattice QCD to compute the second Mellin moments of pion generalized parton distributions and pion electromagnetic form factors. For our calculations we are able to analyze a large set of gauge configurations with 2 dynamical flavours using non-perturbatively the improved Wilson-Sheikholeslami-Wohlert fermionic action pion masses ranging down to 151 MeV. By employing improved smearing we were able to suppress excited state contamination. However, our data in the physical quark mass limit show that some excited state contamination remains. We show the non-zero sink momentum is optimal for the computation of the electromagnetic form factors and generalized form factors at finite momenta.

  3. Pion nucleus optical potential

    International Nuclear Information System (INIS)

    Kam, J. de.

    1981-01-01

    The main goal of the investigations, presented is to establish the contributions to the optical potential, coming from scattering processes which involve 1p-1h nuclear states in the intermediate scattering system. The effects of the Pauli principle corrections and the binding corrections are studied in detail. A phenomenological study of pion absorption effects is also presented. The calculations all concern π- 4 He scattering. The simplicity of the 4 He structure makes the π- 4 He system quite an ideal tool for studying the reaction mechanism. (Auth.)

  4. Effects of the pion string at heavy ion collisions

    CERN Document Server

    Mao, Hong

    2005-01-01

    We study the possible signals of the pion string associated with the QCD chiral phase transition in LHC Pb-Pb collision at energy square root s=5.5 TeV. We follow the Kibble-Zurek mechanism to discuss the production and evolution of the pion string. We will show that if the QCD chiral phase transition really takes place in the LHC Pb-Pb collision process and the phase transition is in the second order, the pion string will be inevitably produced and subsequently decay. The main effect of this phenomenon is that there is a generation of a large number of pions in the final state produced by the decay of the pion string, and these pions are mostly distributed in a low momentum region with p143 MeV; also there are lots of neutral pions distributed in a low momentum region with the mean momentum at p21 Me V.

  5. The future IKO-PION-MUON-facility

    International Nuclear Information System (INIS)

    Goudsmit, P.F.A.; Arnold, H.; Dantzig, R. van; Konijn, J.

    1975-09-01

    Information is given on the pion and muon physics facility planned at the Institute for Nuclear Physics Research (IKO) with special notice of the fluxes of pions and muons expected at this facility, as well as on the structure of these secondary beams

  6. Pion double charge exchange and nuclear structure

    International Nuclear Information System (INIS)

    Ginocchio, J.N.

    1987-01-01

    Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs

  7. ChPT loops for the lattice: pion mass and decay constant, HVP at finite volume and nn̅-oscillations

    Directory of Open Access Journals (Sweden)

    Bijnens Johan

    2018-01-01

    Full Text Available I present higher loop order results for several calculations in Chiral perturbation Theory. 1 Two-loop results at finite volume for hadronic vacuum polarization. 2 A three-loop calculation of the pion mass and decay constant in two-flavour ChPT. For the pion mass all needed auxiliary parameters can be determined from lattice calculations of ππ-scattering. 3 Chiral corrections to neutron-anti-neutron oscillations.

  8. ChPT loops for the lattice: pion mass and decay constant, HVP at finite volume and nn̅-oscillations

    Science.gov (United States)

    Bijnens, Johan

    2018-03-01

    I present higher loop order results for several calculations in Chiral perturbation Theory. 1) Two-loop results at finite volume for hadronic vacuum polarization. 2) A three-loop calculation of the pion mass and decay constant in two-flavour ChPT. For the pion mass all needed auxiliary parameters can be determined from lattice calculations of ππ-scattering. 3) Chiral corrections to neutron-anti-neutron oscillations.

  9. The pion pole term in electroproduction of off-mass-shell pions

    International Nuclear Information System (INIS)

    McKellar, B.H.; Ellis, R.G.

    1983-01-01

    The dependence of the invariant amplitudes for electroproduction of off-mass-shell pions on the pion Born term is investigated when current algebra Ward identities and PCAC are used to determine pion electroproduction invariant amplitudes. The authors show that an amplitude satisfying the Ward identities can be constructed starting from the usual Born terms which do not satisfy them and that this same amplitude will be obtained for a large class of input Born terms

  10. Medical irradiation technique saves lives of victims of Lima inferno

    International Nuclear Information System (INIS)

    2002-01-01

    Full text: Nearly 400 people died when fire swept through a crowded market place in the old centre of Lima, Peru, as the city readied for New Year's Eve, 2001. Yet the lives of more than 60 severely burned people were saved because Peru belongs to a programme, initiated and supported by the International Atomic Energy Agency (IAEA), that permits developing countries to maintain their own tissue banks. 'Tissue grafts are routine treatment in developed countries, said Qian Jihui, Deputy Director General and head of the IAEA Department of Technical Cooperation. 'This programme is saving lives and improving significantly the quality of lives for patients in developing countries.' More than 1600 radiation sterilized tissue packs were provided by Peru's atomic energy institute to eight Lima hospitals and clinics, where nurses and doctors battled to help the fire victims, many of them poor market traders. Peru and six other countries in the IAEA Latin America programme offer patients irradiated sterile human skin and bone from 37 tissue banks for transplant use. IAEA support of tissue banking began in 1983, since when the agency has contributed US $5,313,335 to the programme, resulting in the establishment of 66 tissue banks in the Asia Pacific region, seven in Africa, while the number is growing. Tissue grafts increase the odds for burn patients' survival by reducing the risk of infection. They are also used to treat victims of leprosy. A bone transplant can save a limb. The IAEA has helped develop a system - used in 28 countries - that disinfects tissue grafts in the final package with ionising radiation without damaging them, dramatically lowering the risk of contamination. Now medical authorities in the United States are considering adoption of similar irradiation techniques, following a number of cases of contamination of medical tissue used for transplant. The issue will be among items to be discussed in Vienna, December 2-4, at IAEA headquarters, at a meeting of

  11. Nuclear interactions for 15 GeV/c protons and pions under random and channeling conditions in germanium single crystals

    CERN Document Server

    Andersen, S K; Fich, O.; Golovchenko, J.A.; Nielsen, Henry; Schiott, H.E.; Uggerhoj, E.; Vraast-Thomsen, C.; Charpak, Georges; Petersen, G.; Sauli, F.; Ponpon, J.P.; Siffert, P.

    1978-01-01

    Strong directional effects for nuclear-reaction probabilities have been observed when 15 GeV/ c protons and pions are incident on a 4.2 mm Ge single crystal. In the random situation, our measurements are in agreement with Glauber's theory of diffraction scattering and with published particle-production data. When protons are incident in an aligned direction, the nuclear-reaction probabilities fall off very drastically but in a way which is in agreement with standard channeling theory; for aligned negative pions where a simple channeling theory is lacking, there is some experimental indication that nuclear-reaction probabilities are enhanced compared to the corresponding random rates, an indication which is supported by detailed computer-simulation studies.

  12. The evaluation of the irradiation of medical team in critical X-ray diagnostic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, S; Pavlovic, R [Inst. of Nuclear Science Vinca, Belgrade (Yugoslavia). Radiation and Environmental Protection Lab.; Boreli, F [Fac. of Electrical Engineering, Belgrade (Yugoslavia)

    1996-12-31

    A good realized assessment of the irradiation for any exposed group of population serves as the base for the radiation protection measures (emergency radiation preparedness, radiation protection optimization etc.). This is especially important, by the radiation protection point of view, in contrast X-ray diagnostic techniques - angiographies. This paper presents the way for the realization of the medical team irradiation assessment, based on originally derived simple equations for the scattered radiation field around patient. (author) 1 fig., 3 figs.

  13. Scrutinizing the pion condensed phase

    Energy Technology Data Exchange (ETDEWEB)

    Carignano, Stefano; Mammarella, Andrea; Mannarelli, Massimo [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Lepori, Luca [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Universita dell' Aquila, Dipartimento di Scienze Fisiche e Chimiche, Coppito-L' Aquila (Italy); Pagliaroli, Giulia [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Gran Sasso Science Institute, L' Aquila (Italy)

    2017-02-15

    When the isospin chemical potential exceeds the pion mass, charged pions condense in the zero-momentum state forming a superfluid. Chiral perturbation theory provides a very powerful tool for studying this phase. However, the formalism that is usually employed in this context does not clarify various aspects of the condensation mechanism and makes the identification of the soft modes problematic. We re-examine the pion condensed phase using different approaches within the chiral perturbation theory framework. As a first step, we perform a low-density expansion of the chiral Lagrangian valid close to the onset of the Bose-Einstein condensation. We obtain an effective theory that can be mapped to a Gross-Pitaevskii Lagrangian in which, remarkably, all the coefficients depend on the isospin chemical potential. The low-density expansion becomes unreliable deep in the pion condensed phase. For this reason, we develop an alternative field expansion deriving a low-energy Lagrangian analog to that of quantum magnets. By integrating out the ''radial'' fluctuations we obtain a soft Lagrangian in terms of the Nambu-Goldstone bosons arising from the breaking of the pion number symmetry. Finally, we test the robustness of the second-order transition between the normal and the pion condensed phase when next-to-leading-order chiral corrections are included. We determine the range of parameters for turning the second-order phase transition into a first-order one, finding that the currently accepted values of these corrections are unlikely to change the order of the phase transition. (orig.)

  14. Longitudinal Electroproduction of Charged Pions from

    International Nuclear Information System (INIS)

    David Gaskell; Abdellah Ahmidouch; Pawel Ambrozewicz; H. Anklin; John Arrington; K. Assamagan; Steven Avery; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; D. S. Brown; Roger Carlini; Jinseok Cha; Nicholas Chant; Anthony Cowley; Samuel Danagoulian; D. De Schepper; Jim Dunne; Dipangkar Dutta; Rolf Ent; Liping Gan; Ashot Gasparian; Donald Geesaman; Ron Gilman; Charles Glashausser; Paul Gueye; M. Harvey; O. Hashimoto; Wendy Hinton; G. Hofman; Ceasar Jackson; Hal Jackson; Cynthia Keppel; Ed Kinney; Doug Koltenuk; G. Kyle; Allison Lung; David Mack; D. McKee; Joseph Mitchell; Hamlet Mkrtchyan; B. Mueller; Gabriel Niculescu; Ioana Niculescu; Tom O'Neill; V. Papavassiliou; Dave Potterveld; Juerg Reinhold; Philip Roos; Reyad Sawafta; Ralph Segel; Stepan Stepanyan; Vardan Tadevosyan; T. Takahashi; Liguang Tang; B. Terburg; D. Van Westrum; J. Volmer; T. P. Welch; Stephen Wood; Lulin Yuan; Ben Zeidman; Beni Zihlmann

    2001-01-01

    Separated longitudinal and transverse cross sections for charged pion electroproduction from 1 H, 2 H, and 3 He were measured at Q 2 = 0.4 (GeV/c) 2 for two values of the invariant mass, (bar W) = 1.15 GeV and (bar W) = 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta significantly above the Fermi surface. The longitudinal cross section, if dominated by the pion-pole process, should be sensitive to nuclear pion currents. Comparisons of the longitudinal cross section target ratios to a quasifree calculation reveal a significant suppression in 3> He at (bar W) = 1.60 GeV. The (bar W) = 1.15 GeV results are consistent with simple estimates of the effect of nuclear pion currents, but are also consistent with pure quasifree production

  15. Two pion correlation from SPACER

    International Nuclear Information System (INIS)

    Csoergoe, T.; Zimanyi, J.; Pratt, S.

    1989-12-01

    The correlation function for neutral and negative pions produced in ultrarelativistic heavy ion collisions was calculated without free parameters based on a space-time version of the LUND model, called SPACER: Simulation of Phase space distribution of Atomic nuclear Collisions in Energetic Reactions. This method includes the effect of Bose correlations for the emitted pion pair. Effects arising from correlations between space-time and momentum space distributions are investigated. The results are compared to the data of two different experiments. The role and interpretation of the chaocity parameter are discussed. (D.G.) 14 refs.; 4 figs

  16. Being part of a multi-generational medical practice team.

    Science.gov (United States)

    Hills, Laura

    2010-01-01

    What happens when you find yourself working in your medical practice every day with co-workers who are the ages of your parents or children? Do you find yourself reverting to age-related roles? Do you become exasperated with or bewildered by the values and behaviors of older or younger colleagues? This article explores the challenges and opportunities the medical practice staff member faces when he or she is part of a multi-generational medical practice team. It describes the tensions that often occur when a medical practice staff runs the gamut from those who remember using a library card catalog and those who can't remember the days before Google. It describes the core values, career goals, key formative events, and attitudes that may have shaped the thinking and behavior of the four generations that may work in the medical practice today: Traditionalists, Baby Boomers, Generation X, and Generation Y. It suggests preferred communication and learning methods for staff members of different generations. Finally, this article offers 10 best practices for working in a multi-generational staff and for creating a supportive multi-generational medical practice culture.

  17. Pion correlations in relativistic heavy ion collisions at Heavy Ion Spectrometer Systems (HISS)

    International Nuclear Information System (INIS)

    Christie, W.B. Jr.

    1990-05-01

    This thesis contains the setup, analysis and results of experiment E684H ''Multi-Pion Correlations in Relativistic Heavy Ion Collisions''. The goals of the original proposal were: (1) To initiate the use of the HISS facility in the study of central Relativistic Heavy Ion Collisions (RHIC). (2) To perform a second generation experiment for the detailed study of the pion source in RHIC. The first generation experiments, implied by the second goal above, refer to pion correlation studies which the Riverside group had performed at the LBL streamer chamber. The major advantage offered by moving the pion correlation studies to HISS is that, being an electronic detector system, as opposed to the Streamer Chamber which is a visual detector, one can greatly increase the statistics for a study of this sort. An additional advantage is that once one has written the necessary detector and physics analysis code to do a particular type of study, the study may be extended to investigate the systematics, with much less effort and in a relatively short time. This paper discusses the Physics motivation for this experiment, the experimental setup and detectors used, the pion correlation analysis, the results, and the conclusions possible future directions for pion studies at HISS. If one is not interested in all the details of the experiment, I believe that by reading the sections on intensity interferometry, the section the fitting of the correlation function and the systematic corrections applied, and the results section, one will get a fairly complete synopsis of the experiment

  18. Results from Pion-Carbon Interactions Measured by NA61/SHINE for Improved Understanding of Extensive Air Showers

    CERN Document Server

    Herve, Alexander

    2015-07-21

    The interpretation of extensive air shower measurements, produced by ultra-high energy cosmic rays, relies on the correct modeling of the hadron-air interactions that occur during the shower development. The majority of hadronic particles are produced at equivalent beam energies below the TeV range. NA61/SHINE is a fixed target experiment using secondary beams produced at CERN at the SPS. Hadron-hadron interactions have been recorded at beam momenta between 13 and 350 GeV/c with a wide-acceptance spectrometer. In this contribution we present measurements of the spectra of charged pions and the $\\rho^0$ production in pion-carbon interactions, which are essential for modeling of air showers.

  19. Pion-induced knock-out reactions

    International Nuclear Information System (INIS)

    Jain, B.K.; Phatak, S.C.

    1977-01-01

    A strong absorption model for pion-induced Knock-out reactions is proposed. The distortion of the in-coming and out-going pions has been included by (1) computing pion wave number in nuclear medium (dispersive effect) and (2) excluding the central region of the nucleus where the real pion-absorption is dominant (absorption effect). In order to study the dependence of the (π + π + p) reaction on the off-shell pion-nucleon t-matrix, different off-shell extrapolations are used. The magnitude of the cross-sections seems to be sensitive to the type of off-shell extrapolation; their shapes, however, are similar. The theoretical results are compared with experimental data. The agreement between the theoretical results for separable off-shell extrapolation and the data is good. (author)

  20. Effect of local x-irradiation on mice reproduction in two successive generations

    International Nuclear Information System (INIS)

    Strel'nikova, N.K.; Lisenkova, L.N.

    1978-01-01

    For an experimental assessment of the biologic effectiveness of a single exposure to local irradiation exposure in simulating the conditions of exposure in X ray studies, an experiment was carried out on white mice. Mice of two successive generations were exposed to local X irradiation in the eye region. The radiation was found to bring about changes in the reproductive function (such as sterility, reduced litter size and fertility of females); these changes being dose-dependent in a nonlinear manner. The biologic effect of irradiation was greater in the second-generation mice

  1. Radiative pion-proton scattering

    International Nuclear Information System (INIS)

    Ho-Kim, Q.; Lavine, J.P.

    1977-01-01

    The results are presented of a non-relativistic calculation of the π +- proton bremsstrahlung cross section at the pion kinetic energy of 298 MeV for backward photon angles. The pion-nucleon interaction is given by models that are based on the p-wave Chew-Low theory. An interaction current is included in an attempt to make the overall bremsstrahlung amplitude gauge-invariant. The predicted cross sections show little of the expected resonance, and are in fair agreement with the data. The authors have also calculated the cross sections at other kinetic energies, and have studied effects of the off-mass-shell electromagnetic vertex. (Auth.)

  2. Reports of Perceived Adverse Events of Stimulant Medication on Cognition, Motivation, and Mood: Qualitative Investigation and the Generation of Items for the Medication and Cognition Rating Scale

    Science.gov (United States)

    Kovshoff, Hanna; Banaschewski, Tobias; Buitelaar, Jan K.; Carucci, Sara; Coghill, David; Danckaerts, Marina; Dittmann, Ralf W.; Falissard, Bruno; Grimshaw, Dina Gojkovic; Hollis, Chris; Inglis, Sarah; Konrad, Kerstin; Liddle, Elizabeth; McCarthy, Suzanne; Nagy, Peter; Thompson, Margaret; Wong, Ian C.K.; Zuddas, Alessandro

    2016-01-01

    Abstract Objective: There is no questionnaire to specifically monitor perceived adverse events of methylphenidate (MPH) on cognition, motivation, and mood. The current study therefore had two goals. First, to harvest accounts of such putative events from transcripts of interviews in samples enriched for such potential experiences. Second, to use the derived data to generate items for a new questionnaire that can be used for monitoring such events in medication trials or routine clinical care. Methods: Following a literature search aimed at identifying associations between MPH and cognition and/or motivation, a qualitative semistructured interview was designed to focus specifically on the domains of cognition (i.e., reasoning, depth/breadth of thinking, intellectual capacity, and creativity) and motivation (i.e., drive, effort, and attitudes toward rewards/incentives). Interviews were conducted with 45 participants drawn from the following four groups: (a) clinicians, child and adolescent psychiatrists, and pediatricians specializing in attention-deficit/hyperactivity disorder (ADHD) (n = 15); (2) teachers, with experience of teaching at least 10 medicated children with ADHD (n = 10); (3) parents of children with ADHD (n = 8) treated with MPH; and (4) adolescents/adults with ADHD (n = 12). Purposeful sampling was used to selectively recruit ADHD participants whose histories suggested a degree of vulnerability to MPH adverse events. Data were analyzed using a deductive approach to content analysis. Results: While we probed purposefully for cognitive and motivational adverse events, a third domain, related to mood, emerged from the reports. Therefore, three domains, each with a number of subdomains, were identified from the interview accounts: (i) Cognition (six subdomains; attention/concentration, changes in thinking, reduced creativity, sensory overload, memory, slower processing speed); (ii) motivation (four subdomains; loss of intrinsic motivation

  3. Reports of Perceived Adverse Events of Stimulant Medication on Cognition, Motivation, and Mood: Qualitative Investigation and the Generation of Items for the Medication and Cognition Rating Scale.

    Science.gov (United States)

    Kovshoff, Hanna; Banaschewski, Tobias; Buitelaar, Jan K; Carucci, Sara; Coghill, David; Danckaerts, Marina; Dittmann, Ralf W; Falissard, Bruno; Grimshaw, Dina Gojkovic; Hollis, Chris; Inglis, Sarah; Konrad, Kerstin; Liddle, Elizabeth; McCarthy, Suzanne; Nagy, Peter; Thompson, Margaret; Wong, Ian C K; Zuddas, Alessandro; Sonuga-Barke, Edmund J S

    2016-08-01

    There is no questionnaire to specifically monitor perceived adverse events of methylphenidate (MPH) on cognition, motivation, and mood. The current study therefore had two goals. First, to harvest accounts of such putative events from transcripts of interviews in samples enriched for such potential experiences. Second, to use the derived data to generate items for a new questionnaire that can be used for monitoring such events in medication trials or routine clinical care. Following a literature search aimed at identifying associations between MPH and cognition and/or motivation, a qualitative semistructured interview was designed to focus specifically on the domains of cognition (i.e., reasoning, depth/breadth of thinking, intellectual capacity, and creativity) and motivation (i.e., drive, effort, and attitudes toward rewards/incentives). Interviews were conducted with 45 participants drawn from the following four groups: (a) clinicians, child and adolescent psychiatrists, and pediatricians specializing in attention-deficit/hyperactivity disorder (ADHD) (n = 15); (2) teachers, with experience of teaching at least 10 medicated children with ADHD (n = 10); (3) parents of children with ADHD (n = 8) treated with MPH; and (4) adolescents/adults with ADHD (n = 12). Purposeful sampling was used to selectively recruit ADHD participants whose histories suggested a degree of vulnerability to MPH adverse events. Data were analyzed using a deductive approach to content analysis. While we probed purposefully for cognitive and motivational adverse events, a third domain, related to mood, emerged from the reports. Therefore, three domains, each with a number of subdomains, were identified from the interview accounts: (i) Cognition (six subdomains; attention/concentration, changes in thinking, reduced creativity, sensory overload, memory, slower processing speed); (ii) motivation (four subdomains; loss of intrinsic motivation for goal-directed activities, external

  4. Nucleon multiplicities after pion absorption in 160

    International Nuclear Information System (INIS)

    Hamers, R.

    1989-01-01

    The experiment described in this thesis concerns a simultaneous measurement of two- and higher-fold coincidences following positive and negative pion absorption in 16 0. The detected particles are protons, neutrons and deuterons. The detection and analysis of charged particles is discussed. The incident pion energy was 65 MeV, thus well below the delta resonance. The low pion energy was 65 MeV, thus well below the delta resonance. The low pion energy ensures that contributions of initial state interactions, i.e. pion-nucleon scattering preceding absorption, are minimized. The following reaction channels were selected and analyzed: π + ,pp), (π + ,pd). Evidence for quasifree reaction precessed has been investigated by comparing the data with phase-space calculations incorporating the geometry of the experimental setup. (author). 36 refs.; 1 figs.; 3 tabs

  5. Pair angular correlations for pions, kaons and protons in proton-proton collisions in ALICE

    CERN Document Server

    Zaborowska, Anna

    2014-01-01

    This thesis presents the correlation functions in $\\Delta\\eta\\, \\Delta\\phi$ space for pairs of pions, kaons and protons. The studies were carried out on the set of proton-proton collisions at the centre-of-mass energy $\\sqrt{s}$ = 7 TeV, obtained in ALICE, A Large Ion Collider Experiment at CERN, the European Organization for Nuclear Research. The analysis was performed for two charge combinations (like-sign pairs and unlike-sign pairs) as well as for three multiplicity ranges. Angular correlations are a rich source of information about the elementary particles behaviour. They result in from the interplay of numerous effects, including resonances’ decays, Coulomb interactions and energy and momentum conservation. In case of identical particles quantum statistics needs to be taken into account. Moreover, particles differ in terms of quark content. Kaons, carrying the strange quark obey the strangeness conservation law. In the production of protons baryon number must be conserved. These features are reflected...

  6. Detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Dyakova, A.; Tsvetkova, E.; Nikolova, R.

    2005-01-01

    In connection with the ongoing world application of irradiation as a technology in Food industry for increasing food safety, it became a need for methods of identification of irradiation. It was required to control international trade of irradiated foods, because of the certain that legally imposed food laws are not violated; supervise correct labeling; avoid multiple irradiation. Physical, chemical and biological methods for detection of irradiated foods as well principle that are based, are introducing in this summary

  7. Study on irradiation sterilization of medical gauze pad by incremental dosage method

    International Nuclear Information System (INIS)

    Lei Qing; Huang Min; Deng Wenmin; Wu Ling; Wang Yan; Gao Peng; Du Xiaoying; Xie Yan

    2011-01-01

    To explore the sterilization dose setting method for medical products, the irradiation sterilization dose for medical products was set according to the method 2A of international standard ISO11137 Part 2. The verification dose for medical gauze pad by was set by incremental dose method and with a series of formula. Then the sterilization dose for an SAL of 10 -6 was established by completing the verification dose experiment. The final sterilization dose for medical gauze pad was decided to be 29.7 kGy. This study gives reference for the setting irradiation sterilization dose for medical products which need to adopt the method 2A of international standard ISO11137 Part 2. (authors)

  8. Utilization of pion production accelerators in biomedical applications

    International Nuclear Information System (INIS)

    Rosen, L.

    1979-01-01

    A discussion is presented of biomedical applications of pion-producing accelerators in a number of areas, but with emphasis on pion therapy for treatment of solid, non-metastasized malignancies. The problem of cancer management is described from the standpoint of the physicist, magnitude of the problem, and its social and economic impact. Barriers to successful treatment are identified, mainly with regard to radiation therapy. The properties and characteristics of π mesons, first postulated on purely theoretical grounds by H. Yukawa are described. It is shown how they can be used to treat human cancer and why they appear to have dramatic advantages over conventional forms of radiation by virtue of the fact that they permit localization of energy deposition, preferentially, in the tumor volume. The Clinton P. Anderson Meson Physics Facility (LAMPF), and its operating characteristics, are briefly described, with emphasis on the biomedical channel. The design of a relatively inexpensive accelerator specifically for pion therapy is described as is also the status of clinical trials using the existing Clinton P. Anderson Meson Physics Facility. The advantages of proton over electron accelerator for the production of high quality, high intensity negative pion beams suitable for radiation therapy of malignancies is also addressed. Other current, medically related applications of LAMPF technology are also discussed

  9. Interstitial irradiation for craniopharyngioma

    International Nuclear Information System (INIS)

    Barlas, O.; Bayindir, C.; Can, M.

    2000-01-01

    The results of interstitial irradiation treatment for craniopharyngioma in two patients with six year follow-ups are presented. Stereotactic interstitial irradiation with iodine-125 sources as sole therapy was employed in two adult patients who refused surgical resection. The diagnoses were confirmed by stereotactic biopsy. The first tumour which underwent interstitial irradiation was solid and 4 cm in diameter, and the second, 2.7 cm in diameter, had both cystic and solid components. The implanted iodine-125 seeds delivered 67 Gy and 60 Gy to tumour periphery at the rate of 12 and 14 cGy/h, respectively, were removed at the end of designated radiation periods. Tumour shrinkage and central hypo density, first observed 3 months after irradiation, continued until one tumour shrank to less than 1 cm at 12 months, and the other disappeared completely at 24 months. In both cases functional integrity was restored, and neither radiation induced toxicity nor recurrence has occurred six years after treatment. The results in these two cases suggest that solid craniopharyngiomas are sensitive to interstitial irradiation. (author)

  10. Measurement of the elastic cross section for positive pions on carbon at 142 MeV

    International Nuclear Information System (INIS)

    Oyer, A.T.

    1976-12-01

    A measurement of the elastic cross section dsigma/dΩ was made for the reaction π + + 12 C → π + + 12 C with 142 MeV pions at ten angles ranging from 35 to 85 0 in the laboratory. This experiment was done at the Los Alamos Meson Physics Facility. A double focusing magnetic spectrometer observed a cylindrical styrofoam target. The resulting momentum spectra were recorded by an array of nineteen totally depleted surface barrier detectors located at the spectrometer's focal plane. The spectra from the styrofoam were composed of peaks representing proton elastic, carbon elastic, carbon inelastic, and carbon quasi-elastic channels. A function made of Gaussians representing the two body channels and a distribution representing the quasi-elastic channel was fit to the data using a nonlinear least squares algorithm. The ratio of the carbon elastic to proton elastic cross sections was calculated from the areas of the corresponding Gaussians and then multiplied by the proton elastic cross section of Bugg et al eliminating several sources of systematic errors such as beam normalization. The differential cross sections were found to have the usual diffraction structure with a forward peak and a minimum near 55 0 . Finally, the carbon elastic cross sections were compared to similar π - + 12 C cross sections of Binon et al using the optical model

  11. Measurement of the elastic cross section for positive pions on carbon at 142 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Oyer, A.T.

    1976-12-01

    A measurement of the elastic cross section dsigma/d..cap omega.. was made for the reaction ..pi../sup +/ + /sup 12/C ..-->.. ..pi../sup +/ + /sup 12/C with 142 MeV pions at ten angles ranging from 35 to 85/sup 0/ in the laboratory. This experiment was done at the Los Alamos Meson Physics Facility. A double focusing magnetic spectrometer observed a cylindrical styrofoam target. The resulting momentum spectra were recorded by an array of nineteen totally depleted surface barrier detectors located at the spectrometer's focal plane. The spectra from the styrofoam were composed of peaks representing proton elastic, carbon elastic, carbon inelastic, and carbon quasi-elastic channels. A function made of Gaussians representing the two body channels and a distribution representing the quasi-elastic channel was fit to the data using a nonlinear least squares algorithm. The ratio of the carbon elastic to proton elastic cross sections was calculated from the areas of the corresponding Gaussians and then multiplied by the proton elastic cross section of Bugg et al eliminating several sources of systematic errors such as beam normalization. The differential cross sections were found to have the usual diffraction structure with a forward peak and a minimum near 55/sup 0/. Finally, the carbon elastic cross sections were compared to similar ..pi../sup -/ + /sup 12/C cross sections of Binon et al using the optical model.

  12. Measurement of the elastic cross section for positive pions on carbon at 142 MeV

    International Nuclear Information System (INIS)

    Oyer, A.T.

    1976-01-01

    A measurement of the elastic cross section dsigma/dOMEGA was made for the reaction π + + 12 C yields π + + 12 C with 142 MeV pions at ten angles ranging from 35 to 85 0 in the laboratory. This experiment was done at the Los Alamos Meson Physics Facility. A double focusing magnetic spectrometer observed a cylindrical styrofoam target. The resulting momentum spectra were recorded by an array of nineteen totally depleted surface barrier detectors located at the spectrometers focal plane. The spectra from the styrofoam were composed of peaks representing proton elastic, carbon elastic, carbon inelastic and carbon quasi-elastic channels. A function made of Gaussians representing the two body channels and a distribution representing the quasi-elastic channel was fit to the data using a nonlinear least squares algorithm. The ratio of the carbon elastic to proton elastic cross sections was calculated from the areas of the corresponding Gaussians and then multiplied by the proton elastic cross section of Bugg et al., eliminating several sources of systematic errors such as beam normalization. The differential cross sections were found to have the usual diffraction structure with a forward peak and a minimum near 55 0 . Finally, the carbon elastic cross sections were compared to similar π - + 12 C cross sections of Binon et al., using the optical model

  13. Pion inelastic scattering and the pion-nucleus effective interaction

    International Nuclear Information System (INIS)

    Carr, J.A.

    1983-01-01

    This work examines pion inelastic scattering with the primary purpose of gaining a better understanding of the properties of the pion-nucleus interaction. The main conclusion of the work is that an effective interaction which incorporates the most obvious theoretical corrections to the impulse approximation does a good job of explaining pion elastic and inelastic scattering from zero to 200 MeV without significant adjustments to the strength parameters of the force. Watson's multiple scattering theory is used to develop a theoretical interaction starting from the free pion-nucleon interaction. Elastic scattering was used to calibrate the isoscalar central interaction. It was found that the impulse approximation did poorly at low energy, while the multiple scattering corrections gave good agreement with all of the data after a few minor adjustments in the force. The distorted wave approximation for the inelastic transition matrix elements are evaluated for both natural and unnatural parity excitations. The isoscalar natural parity transitions are used to test the reaction theory, and it is found that the effective interaction calibrated by elastic scattering produces good agreement with the inelastic data. Calculations are also shown for other inelastic and charge exchange reactions. It appears that the isovector central interaction is reasonable, but the importance of medium corrections cannot be determined. The unnatural parity transitions are also reasonably described by the theoretical estimate of the spin-orbit interaction, but not enough systematic data exists to reach a firm conclusion

  14. Late neoplastic changes following medical irradiation

    International Nuclear Information System (INIS)

    Hutchison, G.B.

    1976-01-01

    New additions since 1968 to the literature on radiation carcinogenesis in man support the earlier conclusion of an approximately linear increase in cancer incidence in a broad intermediate dose range for most sites of cancer. Questions are raised regarding the nature of the dose-response relation at very low and at very high dose exposures. Analyses of some data on exposure to radiation from internal deposits of radioactive material suggest that the dose-response curve at low and intermediate ranges is concave up, implying a smaller effect per unit exposure at very low doses than at intermediate ranges. Data on exposure to the very high but anatomically limited doses of radiation used in cancer therapy give conflicting results, suggesting in one report a continuation of the linear relation into the high-dose range. Other reports suggest a lesser effect per unit dose at high doses than at intermediate doses. Extensive laboratory studies of exposure of experimental animals indicate that over broad dose ranges, exceptions to simple linear relations are the rule, and that factors of dose rate and fractionation also affect the dose-response relation

  15. Is medical linac suitable for high-precision stereotactic irradiation? Investigations in geometrical accuracies of gantry and couch

    International Nuclear Information System (INIS)

    Kunieda, Etsuo; Kitamura, Masayuki; Kawaguchi, Osamu; Shigematsu, Naoyuki; Ando, Yutaka; Kubo, Atsushi; Ohira, Takayuki; Tonai, Takenori; Kawase, Takeshi.

    1998-01-01

    Linac-based radiosurgery has many advantages over the gamma knife, including low initial cost and no need of source replacement. On the other hand, most of the medical linacs currently in use were not originally designed to be applied for radiosurgery, and, therefore, careful quality assurance programs are required. In the gantry-head of a linac, a small CCD video camera is mounted in a position optically identical to that of the x-ray source. The video signal from the camera was digitalized to be evaluated for geometrical errors. A metal ball fixed to the stereotactic base frame via XYZ-sliding rods was used as a simulated target. Displacements of the target from the isocenter were measured during rotation of the gantry. Displacements in the gantry-rotation plane were satisfactorily small, while those perpendicular to it were maximal at gantry position angles of 0deg and 180deg. This error might be caused by gravitational vending of the heavy gantry head. Although other major errors of the linac were within one millimeter, the center of coach rotation around the isocenter did not coincide with the center of gantry rotation, probably owing to gravitational vending. Special care should be taken when very small collimators are employed. (author)

  16. Comparing millennial and generation X medical students at one medical school.

    Science.gov (United States)

    Borges, Nicole J; Manuel, R Stephen; Elam, Carol L; Jones, Bonnie J

    2006-06-01

    Two main generational cohorts comprising students enrolled in medical schools today are Generation Xers (born 1965-1980) and Millennial students (born 1981-1999). A subset is Cuspars (born 1975-1980), who share traits with both generations. Population theorists ascribe different personal characteristics, attitudes, and preferences to each group. The authors examined whether selected characteristics describing Generation X and Millennial students were quantifiable using a personality measure. Differences among Generation X, Millennial, and Cuspar medical students were investigated. Eight hundred and nine medical students (399 females and 410 males) who matriculated between 1989-94 and 2001-04 at the Northeastern Ohio Universities College of Medicine completed the 16 Personality Factor Questionnaire (16PF). Differences in responses to the 16PF among the three generations were analyzed using multivariate analysis of variance (MANOVA). Analyses showed significant differences for Generation X versus Millennial students on 10 of the 16 personality factors. Millennial students scored significantly higher than Generation X students on factors including Rule-Consciousness, Emotional Stability, and Perfectionism; Generation X students scored higher than Millennials on Self-Reliance. Millennials also were significantly different from Generation Xers on several other factors. Significant differences were noted among Cuspars, Generation Xers, and Millennials. The 16PF is a useful tool to examine differences among these groups and to help understand the factors that constitute their personalities. Given differences among the generational groups, the authors forecast possible educational implications for medical school academic affairs and student services, and suggest areas for future research.

  17. A pilot study to determine medical laser generated air contaminant emission rates for a simulated surgical procedure.

    Science.gov (United States)

    Lippert, Julia F; Lacey, Steven E; Lopez, Ramon; Franke, John; Conroy, Lorraine; Breskey, John; Esmen, Nurtan; Liu, Li

    2014-01-01

    The U.S. Occupational Safety and Health Administration (OSHA) estimates that half a million health-care workers are exposed to laser surgical smoke each year. The purpose of this study was to establish a methodology to (1) estimate emission rates of laser-generated air contaminants (LGACs) using an emission chamber, and to (2) perform a screening study to differentiate the effects of three laser operational parameters. An emission chamber was designed, fabricated, and assessed for performance to estimate the emission rates of gases and particles associated with LGACs during a simulated surgical procedure. Two medical lasers (Holmium Yttrium Aluminum Garnet [Ho:YAG] and carbon dioxide [CO2]) were set to a range of plausible medical laser operational parameters in a simulated surgery to pyrolyze porcine skin generating plume in the emission chamber. Power, pulse repetition frequency (PRF), and beam diameter were evaluated to determine the effect of each operational parameter on emission rate using a fractional factorial design. The plume was sampled for particulate matter and seven gas phase combustion byproduct contaminants (benzene, ethylbenzene, toluene, formaldehyde, hydrogen cyanide, carbon dioxide, and carbon monoxide): the gas phase emission results are presented here. Most of the measured concentrations of gas phase contaminants were below their limit of detection (LOD), but detectable measurements enabled us to determine laser operation parameter influence on CO2 emissions. Confined to the experimental conditions of this screening study, results indicated that beam diameter was statistically significantly influential and power was marginally statistically significant to emission rates of CO2 when using the Ho:YAG laser but not with the carbon dioxide laser; PRF was not influential vis-a-vis emission rates of these gas phase contaminants.

  18. Pion-nucleus scattering in the isobar formalism

    International Nuclear Information System (INIS)

    Moniz, E.J.

    1978-06-01

    Lectures on the isobar-hole model for pion reactions include the isobar as an explicit degree of freedom and the connection with a purely pion and nucleon system, the formalism and its relation to the pion optical potential, the extended schematic model for pion scattering, a simple spinless s-wave model, application to pion-oxygen 16 scattering and comparison with elastic scattering data. In this way the extent is shown to which microscopic treatment of the many-body dynamics explains the data and the extent to which additional physical input is required. Another test is the various inelastic processes. Inclusive reactions are briefly discussed. 37 references

  19. Study of the magnetic form factor of 13C by measurement of radiative pion capture at high momentum transfer: search for precursors to pion condensation

    International Nuclear Information System (INIS)

    Crowe, K.M.

    1982-01-01

    By studying radiative capture in flight, information can be obtained on the energy and momentum transfer dependence of nuclear transition densities containing the spin. These are of interest from a nuclear structure point of view, as well as in connection with discussions of exotic phenomena such as pion condensation and opalescence. This report presents preliminary results of measurements of 1 H(π - ,γ)n at T = 113 MeV and 13 C(π + ,γ) 13 N g.s. at T = 115 MeV. (Auth.)

  20. The pion-nucleus interaction

    International Nuclear Information System (INIS)

    Afnan, I.R.

    1977-04-01

    The latest developments in the construction of pion-nucleus optical potential are presented and a comparison with the latest data on π+ 12 C is made. The suggested mechanisms for the (p,π) reaction are discussed with a comparison of the theoretical results with experiment. (Author)

  1. Funny hills in pion spectra from heavy-ion collisions

    International Nuclear Information System (INIS)

    Rasmussen, J.O.

    1982-03-01

    A discussion of some of the systematic features of the pion spectra in heavy-ions reactions is given. A discussion of the hills and valleys in heavy ion pion spectra that show up at the lower pion energies is given. The following topics are discussed: (1) three kinds of funny hills; (2) π - / + ratios near center of mass; (3) new Monte Carlo studies of charged pion spectra; and (4) pion orbiting about fireballs and Bose-Einstein behavior as explanation for the mid-rapidity P/sub perpendicular to/ approx. = 0.4 to 0.5 m/sub π/c hill

  2. Generation of hourly irradiation synthetic series using the neural network multilayer perceptron

    Energy Technology Data Exchange (ETDEWEB)

    Hontoria, L.; Aguilera, J. [Universidad de Jaen, Linares-Jaen (Spain). Dpto. de Electronica; Zufiria, P. [Ciudad Universitaria, Madrid (Spain). Grupo de Redes Neuronales

    2002-05-01

    In this work, a methodology based on the neural network model called multilayer perceptron (MLP) to solve a typical problem in solar energy is presented. This methodology consists of the generation of synthetic series of hourly solar irradiation. The model presented is based on the capacity of the MLP for finding relations between variables for which interrelation is unknown explicitly. The information available can be included progressively at the series generator at different stages. A comparative study with other solar irradiation synthetic generation methods has been done in order to demonstrate the validity of the one proposed. (author)

  3. [Medical data warehousing as a generator of system component for decision support in health care].

    Science.gov (United States)

    Catibusić, Sulejman; Hadzagić-Catibusić, Feriha; Zubcević, Smail

    2004-01-01

    Growth in role of data warehousing as strategic information for decision makers is significant. Many health institutions have data warehouse implementations in process of development or even in production. This article was made with intention to improve general understanding of data warehousing requirements form the point of view of end-users, and information system as well. For that reason, in this document advantages and arguments for implementation, techniques and methods of data warehousing, data warehouse foundation and exploration of information as final product of data warehousing process have been described.

  4. Generating classes of 3D virtual mandibles for AR-based medical simulation.

    Science.gov (United States)

    Hippalgaonkar, Neha R; Sider, Alexa D; Hamza-Lup, Felix G; Santhanam, Anand P; Jaganathan, Bala; Imielinska, Celina; Rolland, Jannick P

    2008-01-01

    Simulation and modeling represent promising tools for several application domains from engineering to forensic science and medicine. Advances in 3D imaging technology convey paradigms such as augmented reality (AR) and mixed reality inside promising simulation tools for the training industry. Motivated by the requirement for superimposing anatomically correct 3D models on a human patient simulator (HPS) and visualizing them in an AR environment, the purpose of this research effort was to develop and validate a method for scaling a source human mandible to a target human mandible within a 2 mm root mean square (RMS) error. Results show that, given a distance between 2 same landmarks on 2 different mandibles, a relative scaling factor may be computed. Using this scaling factor, results show that a 3D virtual mandible model can be made morphometrically equivalent to a real target-specific mandible within a 1.30 mm RMS error. The virtual mandible may be further used as a reference target for registering other anatomic models, such as the lungs, on the HPS. Such registration will be made possible by physical constraints among the mandible and the spinal column in the horizontal normal rest position.

  5. Search for Rare Multi-Pion Decays of the Tau Lepton Using the BABAR Detector

    Energy Technology Data Exchange (ETDEWEB)

    Ter-Antonyan, Ruben [The Ohio State Univ., Columbus, OH (United States)

    2007-09-18

    A search for the decay of the τ lepton to rare multi-pion final states is performed using the BABAR detector at the PEP-II asymmetric-energy e+e- collider. The analysis uses 232 fb-1 of data at center-of-mass energies on or near the Y(4S) resonance. In the search for the τ- → 3π-+0vτ decay, we observe 10 events with an expected background of 6.5$+2.0\\atop{-1.4}$ events. In the absence of a signal, we calculate the decay branching ratio upper limit β(τ- → 3π-2π+2π0vτ) < 3.4 x 10-6 at the 90% confidence level. This is more than a factor of 30 improvement over the previously established limit. In addition, we search for the exclusive decay mode τ- → 2ωπ-vτ with the further decay of ω →π-π+π0. We observe 1 event, expecting 0.4$+1.0\\atop{-0.4}$ background events, and calculate the upper limit βτ-→ 2ωπ-vτ < 5.4 x 10-7 at the 90% confidence level. This is the first upper limit for this mode.

  6. Photon flux determination for a precision measurement of the neutral pion lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Teymurazyan, Aram [Univ. of Kentucky, Lexington, KY (United States)

    2008-01-01

    The Jefferson Lab Hall B PrimEx Collaboration is using tagged photons to perform a 1.4% level measurement of the absolute cross section for the photo-production of neutral pions in the Coulomb field of a nucleus as a test of Chiral Perturbation Theory. Such a high precision pushes the limits of the photon tagging technique in regards to the determination of the absolute photon flux. A multifaceted approach to this problem has included measuring the absolute tagging ratios with a Total Absorption Counter (TAC) as well as relative tagging ratios with a Pair Spectrometer (PS), and determining the rate of the tagging counters using multi-hit TDC's and a clock trigger. This enables the determination of the absolute tagged photon flux for the PrimEx experiment with uncertainty of ~ 1.0%, which is unprecedented. In view of the stringent constraints on the required precision of the photon flux for this experiment, periodicmeasurements of the pair production cross section were performed throughout the run. In these measurements, both the photon energy and flux were determined by the Jefferson Lab Hall B tagger, and the electron-positron pairs were swept by a magnetic field and detected in the new 1728 channel hybrid calorimeter (HyCal). The pair production crosssection was extracted with an uncertainty of ~ 2%, producing an agreement with theoretical calculations at the level of ~ 2%. This measurement provided a unique opportunity to verify the photon flux determination procedure for the PrimEx experiment.

  7. 238Pu based energy micro-generation sources for medical applications

    International Nuclear Information System (INIS)

    Boucher, Rene

    1968-10-01

    Pace-makers are frequently implanted in the human body. The existing apparatus are, actually, equipped with chemical piles with a lifetime of about 15 months. The use of 238 Pu will provide a pace-maker with an autonomy of 10 years at least. Principal problems of security due to the use of plutonium are considered. It is advisable to improve the properties of pure plutonium by small additions of elements such as cerium, scandium, indium, gallium or americium. A number of the most important properties for a pace-maker source are presented. Finally, the fabrication and canning of the source are surveyed. (author) [fr

  8. Medical and Biohazardous Waste Generator's Guide (Revision 2)

    International Nuclear Information System (INIS)

    Waste Management Group

    2006-01-01

    These guidelines describe procedures to comply with all Federal and State laws and regulations and Lawrence Berkeley National Laboratory (LBNL) policy applicable to State-regulated medical and unregulated, but biohazardous, waste (medical/biohazardous waste). These guidelines apply to all LBNL personnel who: (1) generate and/or store medical/biohazardous waste, (2) supervise personnel who generate medical/biohazardous waste, or (3) manage a medical/biohazardous waste pickup location. Personnel generating biohazardous waste at the Joint Genome Institute/Production Genomics Facility (JGI/PGF) are referred to the guidelines contained in Section 9. Section 9 is the only part of these guidelines that apply to JGI/PGF. Medical/biohazardous waste referred to in this Web site includes biohazardous, sharps, pathological and liquid waste. Procedures for proper storage and disposal are summarized in the Solid Medical/Biohazardous Waste Disposal Procedures Chart. Contact the Waste Management Group at 486-7663 if you have any questions regarding medical/biohazardous waste management

  9. Differences in motives between Millennial and Generation X medical students.

    Science.gov (United States)

    Borges, Nicole J; Manuel, R Stephen; Elam, Carol L; Jones, Bonnie J

    2010-06-01

    OBJECTIVES Three domains comprise the field of human assessment: ability, motive and personality. Differences in personality and cognitive abilities between generations have been documented, but differences in motive between generations have not been explored. This study explored generational differences in medical students regarding motives using the Thematic Apperception Test (TAT). METHODS Four hundred and twenty six students (97% response rate) at one medical school (Generation X = 229, Millennials = 197) who matriculated in 1995 & 1996 (Generation X) or in 2003 & 2004 (Millennials) wrote a story after being shown two TAT picture cards. Student stories for each TAT card were scored for different aspects of motives: Achievement, Affiliation, and Power. RESULTS A multiple analysis of variance (p Millennials' and Generation X-ers' needs for Power on both TAT cards and needs for Achievement and Affiliation on one TAT card. The main effect for gender was significant for both TAT cards regarding Achievement. No main effect for ethnicity was noted. CONCLUSIONS Differences in needs for Achievement, Affiliation and Power exist between Millennial and Generation X medical students. Generation X-ers scored higher on the motive of Power, whereas Millennials scored higher on the motives of Achievement and Affiliation.

  10. Medical and biohazardous waste generator`s guide: Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This Guide describes the procedures required to comply with all federal and state laws and regulations and Lawrence Berkeley Laboratory (LBL) policy applicable to medical and biohazardous waste. The members of the LBL Biological Safety Subcommittee participated in writing these policies and procedures. The procedures and policies in this Guide apply to LBL personnel who work with infectious agents or potentially infectious agents, publicly perceived infectious items or materials (e.g., medical gloves, culture dishes), and sharps (e.g., needles, syringes, razor blades). If medical or biohazardous waste is contaminated or mixed with a hazardous chemical or material, with a radioactive material, or with both, the waste will be handled in accordance with the applicable federal and State of California laws and regulations for hazardous, radioactive, or mixed waste.

  11. Accelerating and focusing structures for PIGMI

    International Nuclear Information System (INIS)

    Swenson, D.A.; Bush, E.D. Jr.; Holsinger, R.F.; Manca, J.J.; Saito, N.; Stovall, J.E.

    1977-01-01

    The National Cancer Institute is supporting a program of accelerator development at the Los Alamos Scientific Laboratory aimed at the extension of proton linac technologies to produce the most suitable Pion Generator for Medical Irradiations (PIGMI). An optimized design of a pion generator suitable for a radiotherapy program at a major medical center has been established, consisting of a 250-keV injector, followed by a 35-meter-long drift-tube linac that accelerates the proton beam to 150 MeV, and an 85-meter-long coupled-cavity linac that accelerates the beam to its final energy of 650 MeV, where the average beam current of 100 microamperes impinges on one or more targets producing abundant quantities of π - mesons for radiotherapeutic applications. A number of extensions to proton linac technology are being pursued under the PIGMI program at LASL. A discussion is given of recent developments in three areas relevant to the acceleration and focusing of proton beams, namely, the alternating phase focused (APF) linac structure, the disk and washer linac structure, and small permanent magnet quadrupole lenses. The APF linac structure is being developed for the acceleration and focusing role from the injection energy of 250 keV to a few MeV, where a transition is made to a permanent magnet quadrupole focused linac structure. The disk and washer linac structure is under consideration for the high velocity portion of the design

  12. Backward pion photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Sibirtsev, A; Haidenbauer, J; Huang, F; Krewald, S; Meissner, U -G

    2009-04-01

    We present a systematic analysis of backward pion photoproduction for the reactions $ \\gamma$ p $ \\rightarrow$ $ \\pi^{0}_{}$ p and $ \\gamma$ p $ \\rightarrow$ $ \\pi^{+}_{}$ n . Regge phenomenology is applied at invariant collision energies above 3GeV in order to fix the reaction amplitude. A comparision with older data on $ \\pi^{0}_{}$ - and $ \\pi^{+}_{}$ -photoproduction at $ \\vartheta$ = 180° indicates that the high-energy limit as given by the Regge calculation could be reached possibly at energies of around $ \\sqrt{{s}}$ ≃ 3 GeV. In the energy region of $ \\sqrt{{s}}$ $ \\le$2.5 GeV, covered by the new measurements of $ \\gamma$ p $ \\rightarrow$ $ \\pi^{0}_{}$ p differential cross-sections at large angles at ELSA, JLab, and LEPS, we see no clear signal for a convergence towards the Regge results. The baryon trajectories obtained in our analysis are in good agreement with those given by the spectrum of excited baryons.

  13. Pion observables and QCD

    International Nuclear Information System (INIS)

    Roberts, C.D.

    1995-01-01

    Herein the application of the DSE approach to the calculation of pion observables is described using: the π-π scattering lengths (a 0 0 , a 2 0 , a 1 1 , a 0 2 , a 2 2 ) and associated partial wave amplitudes; the π 0 → γγ decay width; and the charged pion form factor, F π (q 2 ), as illustrative examples. Since this approach provides a straightforward, microscopic description of dynamical chiral symmetry breaking (DχSB) and confinement, the calculation of pion observables is a simple and elegant illustrative example of its power and efficacy. (orig.)

  14. Learning about nucleon resonances with pion photoproduction

    International Nuclear Information System (INIS)

    Walker, R.L.

    1989-01-01

    This chapter charts the discovery of nucleon resonances from pion-nucleon interactions. It was not until after the Albuquerque meeting in 1953 the experimentalists were able to persuade physicists about the existence of this phenomenon with the discovery of the P 33 resonance. The second and third resonances to be discovered, D 13 and F 15 , were seen as peaks in the total cross section for pion plus photoproduction, from 1956 onwards. Knowledge of pion-nucleon scattering has played an important role in the development of quark models. (UK)

  15. A new determination of the pion mass

    International Nuclear Information System (INIS)

    Anagnastopoulos, D.; Belmiloud, D.; El-Khoury, P.; Indelicato, P.; Borchert, G.; Gorke, H.; Gotta, D.; Lenz, S.; Siems, T.; Daum, M.; Frosch, R.; Hauser, P.; Kirch, K.; Simons, L.M.

    1996-01-01

    Initial measurements concerning the feasibility of a new pion mass determination are described. In a first step, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high pion stopping density, sufficient to check predictions for the cascade process and to measure the stability of the apparatus. A comparison with the measured Cu K α fluorescence line resolves an ambiguity in the value of the pion mass. The preliminary result from this experiment is m π -=(139.57040±0.00045) MeV/c 2 . (orig.)

  16. arXiv Search for sterile neutrinos decaying into pions at the LHC

    CERN Document Server

    Dib, Claudio O.; Neill, Nicolás A.; Yuan, Xing-Bo

    2018-02-28

    We study the possibility to observe sterile neutrinos with masses in the range 5  GeVpions, namely W→ℓN→nπℓℓ (n=1,2,3). The two pion and three pion modes require extrapolations of form factors to large time-like q2, which we do using vector dominance models as well as light front holographic QCD, with remarkable agreement. This mass region is difficult to explore with inclusive ℓℓjj modes or trilepton modes and impossible to explore in rare meson decays. While particle identification is a real challenge in these modes, vertex displacement due to the long living neutrino in the above mass range can greatly help reduce backgrounds. Assuming a sample of 109  W bosons at the end of the LHC Run 2, these modes could discover a sterile neutrino in the above mass range or improve the current bounds on the heavy-to-light lepton mixings by an order of magnitude, |UℓN|2∼2×10-6. Moreover, by studying the equal s...

  17. Radiation facilities and irradiation technology for food irradiation

    International Nuclear Information System (INIS)

    Sunaga, Hiromi

    2005-01-01

    Progress made during these 30 years in the field of radiation treatment of food is reviewed by describing features of the process including elementary processes, quality control of the products and the dosimetric techniques widely employed. The Co-60 gamma-ray irradiation facilities to be used for radiation-sterilization of medical supplies and food preservation are presented. For electron beam irradiation, accelerators for processing with the energy from 0.3 to 10 MeV are generally employed. The electron-guns, the method of acceleration such as rectification, types of acceleration as Cockcroft-Walton, dynamitron, or linear acceleration and X-ray producing facility, with various countermeasures for safety management, are briefly explained. The concepts of dose and traceability are given. The dosimeters including reference dosimeter and routine ones with validation are explained. (S. Ohno)

  18. Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications

    Science.gov (United States)

    Kühn, S.; Bibinov, N.; Gesche, R.; Awakowicz, P.

    2010-01-01

    A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O3, correspondingly, are generated.

  19. Variability generation in sugar cane for resistance to mosaic viruses and rusts (puccinia melanocephala) by means of the cultivation of explants and irradiated callus

    International Nuclear Information System (INIS)

    Ventura Gonzalez, Morella Fuchs; Castroni, Sonia; Diaz, Ezequiel

    1997-01-01

    With the purpose to generate sugar cane variability in vitro, in order the obtain genotypes resistant to the mosaic viruses and to the rusts (Puccinia melanocephala), callus coming from cultivars susceptible to the mosaic viruses (B 6749, B 7987 and PR 62258) and to the rusts (B 4362 and PR 641791) were irradiated with different gamma radiation dose. The IVIC cobalt source was used, being applied two, four, eight and twelve krads. The effect of irradiation on the percentage of regeneration of plants for each dose and variety was evaluated. The regenerated plants were taken to shelter, where they were inoculated with the mosaic viruses B (SCMB-B). The asymptomatic subclons were transplanted to field in August of 1992, to evaluate the presence of symptoms of mosaic and rusts. A high proportion of the plants didn't show symptoms of illnesses, being obtained 2,35% of sick plants coming from cultivar B 6749 and 0,72 from cultivar PR 62258. This low incidence of infection remained stable up to the following year of evaluation. The genetic variation was studied through isoenzymatics pattern, peroxidase specifically. This analysis allowed to detect variation in the number and intensity of the bands among the subclons and in the original variety. 229 subclons were selected from cultivar B 6749 and they were incorporated to the program of cultivation improvement. Among them 60 subclons, with good agronomic and productivity characteristics, were chosen and continue being evaluated to be incorporated to the regional essays, last phase of the selection process [es

  20. Determination of the pion charge form factor for Q2 = 0.60-1.60 (GeV/c)2

    International Nuclear Information System (INIS)

    Vardan Tadevosyan; Henk Blok; Garth Huber; David Abbott; Heinz Anklin; Christopher Armstrong; John Arrington; Ketevi Assamagan; Steven Avery; O. Baker; C. Bochna; Edward Brash; Herbert Breuer; Nicholas Chant; James Dunne; T. Eden; Rolf Ent; David Gaskell; Ronald Gilman; Kenneth Gustafsson; Wendy Hinton; Harold Jackson; Mark Jones; Cynthia Keppel; Pyunghun Kim; Wooyoung Kim; Andreas Klein; Douglas Koltenuk; Meihua Liang; George Lolos; Allison Lung; David Mack; David McKee; David Meekins; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Gabriel Niculescu; Maria-Ioana Niculescu; David Pitz; David Potterveld; Liming Qin; Joerg Reinhold; Ilkyoung Shin; Stepan Stepanyan; Liguang Tang; Rob van der Meer; Kelley Vansyoc; D. Van Westrum; Jochen Volmer; William Vulcan; Stephen Wood; Chen Yan; Wenxia Zhao; Benedikt Zihlmann

    2006-01-01

    The data analysis for the reaction H(e,e(prime) pi + )n, which was used to determine values for the charged pion form factor Fpi for values of Q2 = 0.6-1.6 (gEv/C) 2 , has been repeated with careful inspection of all steps and special attention to systematic uncertainties. Also the method used to extract Fpi from the measured longitudinal cross section was critically reconsidered. Final values for the separated longitudinal and transverse cross sections and the extracted values of Fpi are presented

  1. Process for irradiation of polyethylene

    International Nuclear Information System (INIS)

    White, George.

    1983-01-01

    Irradiation of polyethylene affects its processabiltiy in the fabrication of products and affects the properties of products already fabricated. The present invention relates to a process for the irradiation of polyethylene, and especially to a process for the irradiation of homopolymers of ethylene and copolymers of ethylene and higher α-olefins, in the form of granules, with low levels of electron or gamma irradiation in the presence of an atomsphere of steam

  2. In vitro and in vivo studies of the TRIUMF pion therapy beam

    International Nuclear Information System (INIS)

    Skarsgard, L.D.; Douglas, B.G.; Denekamp, J.; Chaplin, D.J.; Lam, G.K.; Harrison, R.W.; Kornelsen, R.O.; Palcic, B.

    1985-01-01

    Patient treatments at TRIUMF (Tri-University Meson Facility, Vancouver, B. C.) use a moving spot raster scan technique where the pion range is modulated in depth for each position of the moving spot. The spot scans in a stepwise fashion and can produce any desired field shape. This approach provides very good dose uniformity across the treatment field and allows maximum flexibility in shaping the treatment volume. Survival of cultured cells has been used as a biological dosimeter to test the isoeffectiveness of the pion dose distributions, which must be shaped in depth to compensate for the depth-dependent LET distribution. Isoeffectiveness across the treatment field has also been verified using this system, which involves irradiating cells supported in a gelatin matrix. The response of pig skin to pion irradiation at TRIUMF has provided a check on the in vivo RBE for acute effects derived from our earlier studies with mouse foot. In addition, the pig skin reactions have been followed for several months to assess the later dermal response. The RBE of our pion beam relative to 270 kVp X rays is approximately 1.5 for both the acute epidermal and the later dermal responses

  3. Theoretical contributions to coherent pion production in subthreshold and relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Deutchman, P.A.; Norbury, J.W.; Townsend, L.W.

    1986-01-01

    The analysis results from a microscopic calculation for pion production in heavy-ion collisions at intermediate to relativistic energies both above and below pion threshold are presented and the most important terms that contribute to the pion spectrum are determined. The energy dependence and the effects on the pion spectrum due to the various parameters in the theory are examined. The model is applied to coherent pion-production in 16 O + 12 C collisions. (orig.)

  4. In-medium pion valence distributions in a light-front model

    Energy Technology Data Exchange (ETDEWEB)

    Melo, J.P.B.C. de, E-mail: joao.mello@cruzeirodosul.edu.br [Laboratório de Física Teórica e Computacional – LFTC, Universidade Cruzeiro do Sul, 01506-000 São Paulo (Brazil); Tsushima, K. [Laboratório de Física Teórica e Computacional – LFTC, Universidade Cruzeiro do Sul, 01506-000 São Paulo (Brazil); Ahmed, I. [Laboratório de Física Teórica e Computacional – LFTC, Universidade Cruzeiro do Sul, 01506-000 São Paulo (Brazil); National Center for Physics, Quaidi-i-Azam University Campus, Islamabad 45320 (Pakistan)

    2017-03-10

    Pion valence distributions in nuclear medium and vacuum are studied in a light-front constituent quark model. The in-medium input for studying the pion properties is calculated by the quark-meson coupling model. We find that the in-medium pion valence distribution, as well as the in-medium pion valence wave function, are substantially modified at normal nuclear matter density, due to the reduction in the pion decay constant.

  5. Corrections to the one-pion exchange amplitudes for the reaction np→pΔsub(33)sup(deg)

    International Nuclear Information System (INIS)

    Ferraz De Camargo, A.; Laville, J.L.

    1978-01-01

    A simple modified one-pion exchange model is applied to the analysis of the reaction np→pΔsub(33)sup(deg) from 1.39 to 1.90GeV/c. It is shown that important corrections to the evasive amplitudes can account for the turnover observed in the differential cross-section and rather good fits are obtained. Such corrections do not agree with the prescription known as ''poor man's absorption''. The results for the density matrix elements are briefly discussed

  6. Blue light irradiation-induced oxidative stress in vivo via ROS generation in rat gingival tissue.

    Science.gov (United States)

    Yoshida, Ayaka; Shiotsu-Ogura, Yukako; Wada-Takahashi, Satoko; Takahashi, Shun-suke; Toyama, Toshizo; Yoshino, Fumihiko

    2015-10-01

    It has been reported that oxidative stress with reactive oxygen species (ROS) generation is induced by blue light irradiation to a living body. Only limited research has been reported in dental field on the dangers of blue light, mostly focusing on cytotoxicity associated with heat injury of dental pulp. We thus performed an in vivo study on oral tissue exposed to blue light. ROS generated upon blue light irradiation of flavin adenine dinucleotide were measured by electron spin resonance spectroscopy. After blue light irradiation, the palatal gingiva of Wistar rats were isolated. Collected samples were subjected to biochemical analysis of lipid peroxidation and glutathione. Singlet oxygen was generated by blue light irradiation, but was significantly quenched in an N-acetyl-L-cysteine (NAC) concentration-dependent manner. Blue light significantly accelerated oxidative stress and increased the oxidized glutathione levels in gingival tissue. These effects were also inhibited by NAC pre-administration. The results suggest that blue light irradiation at clinical levels of tooth bleaching treatment may enhance lipid peroxidation by the induction of oxidative stress and the consumption of a significant amount of intracellular glutathione. In addition, NAC might be an effective supplement for the protection of oral tissues against blue light irradiation-induced oxidative damage. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Medical irradiation, radioactive waste and misinformation. A press release from the French Academy of Medicine

    International Nuclear Information System (INIS)

    The, G. de; Tubiana, M.

    2002-01-01

    The Academy of Medicine, worried by the problems that poses for public opinion the medical irradiation, the radioactive wastes and some erroneous information that these subjects give rise to, considers useful to give an advice based on objective data. (N.C.)

  8. Pion double charge exchange

    International Nuclear Information System (INIS)

    Cooper, M.D.

    1978-01-01

    The pion double charge exchange data on the oxygen isotopes is reviewed and new data on 9 Be, 12 C, 24 Mg, and 28 Si are presented. Where theoretical calculations exist, they are compared to the data. 9 references

  9. Pion in a box

    International Nuclear Information System (INIS)

    Bietenholz, W.; Rakow, P.E.L.; Schierholz, G.; Regensburg Univ.

    2010-02-01

    The residual mass of the pion in a finite spatial box at vanishing quark masses is computed with two flavors of dynamical clover fermions. The result is compared with predictions of chiral perturbation theory in the δ regime. (orig.)

  10. Impact of problem-based, active learning on graduation rates for 10 generations of Dutch medical students.

    Science.gov (United States)

    Schmidt, Henk G; Cohen-Schotanus, Janke; Arends, Lidia R

    2009-03-01

    We aimed to study the effects of active-learning curricula on graduation rates of students and on the length of time needed to graduate. Graduation rates for 10 generations of students enrolling in the eight Dutch medical schools between 1989 and 1998 were analysed. In addition, time needed to graduate was recorded. Three of the eight schools had curricula emphasising active learning, small-group instruction and limited numbers of lectures; the other five had conventional curricula to varying degrees. Overall, the active-learning curricula graduated on average 8% more students per year, and these students graduated on average 5 months earlier than their colleagues from conventional curricula. Four hypotheses potentially explaining the effect of active learning on graduation rate and study duration were considered: (i) active-learning curricula promote the social and academic integration of students; (ii) active-learning curricula attract brighter students; (iii) active-learning curricula retain more poor students, and (iv) the active engagement of students with their study required by active-learning curricula induces better academic performance and, hence, lower dropout rates. The first three hypotheses had to be rejected. It was concluded that the better-learning hypothesis provides the most parsimonious account for the data.

  11. Pion-nucleus cross sections approximation

    International Nuclear Information System (INIS)

    Barashenkov, V.S.; Polanski, A.; Sosnin, A.N.

    1990-01-01

    Analytical approximation of pion-nucleus elastic and inelastic interaction cross-section is suggested, with could be applied in the energy range exceeding several dozens of MeV for nuclei heavier than beryllium. 3 refs.; 4 tabs

  12. Low energy theorems in pion production

    International Nuclear Information System (INIS)

    Holstein, B.R.; Washington Univ., Seattle, WA

    1992-01-01

    Considerable activity-both theoretical and experimental-has recently taken place involving the threshold and near threshold of pion photo- and electroproduction. This activity is herein summarized and a program for future work is outlined

  13. Dose Profiles in ECAL Crystals for Various Irradiation Conditions

    CERN Document Server

    Huhtinen, Mika

    1998-01-01

    Simulated dose profiles in various irradiation and beam test conditions are compared to the expected dose profiles in the ECAL crystals at LHC. Simple front or side irradiations with photons give too steep or too flat dose profiles, respectively. Thus, if dose maxima are fitted to agree, front irradiation underestimate the average dose whereas side irradiations tend to overestimate. Different profiles are difficult to compare reliably, but it seems likely that in both cases the discrepancy is about a factor of 2-3 but in different directions. For most purposes this is likely to be good enough, but should be taken into account in the interpretation of the test results. It is shown that using a customized lead mask between the source and the crystal can significantly improve the agreement between 60 Co side irradiations and the LHC predictions. A 400 MeV/c pion beam incident on a crystal matrix can also reproduce rather well the profiles expected in the barrel ECAL.

  14. A new generation of tools for search, recovery and quality evaluation of World Wide Web medical resources.

    Science.gov (United States)

    Aguillo, I

    2000-01-01

    Although the Internet is already a valuable information resource in medicine, there are important challenges to be faced before physicians and general users will have extensive access to this information. As a result of a research effort to compile a health-related Internet directory, new tools and strategies have been developed to solve key problems derived from the explosive growth of medical information on the Net and the great concern over the quality of such critical information. The current Internet search engines lack some important capabilities. We suggest using second generation tools (client-side based) able to deal with large quantities of data and to increase the usability of the records recovered. We tested the capabilities of these programs to solve health-related information problems, recognising six groups according to the kind of topics addressed: Z39.50 clients, downloaders, multisearchers, tracing agents, indexers and mappers. The evaluation of the quality of health information available on the Internet could require a large amount of human effort. A possible solution may be to use quantitative indicators based on the hypertext visibility of the Web sites. The cybermetric measures are valid for quality evaluation if they are derived from indirect peer review by experts with Web pages citing the site. The hypertext links acting as citations need to be extracted from a controlled sample of quality super-sites.

  15. Pion interferometric tests of transport models

    Energy Technology Data Exchange (ETDEWEB)

    Padula, S.S.; Gyulassy, M.; Gavin, S. (Lawrence Berkeley Lab., CA (USA). Nuclear Science Div.)

    1990-01-08

    In hadronic reactions, the usual space-time interpretation of pion interferometry often breaks down due to strong correlations between spatial and momentum coordinates. We derive a general interferometry formula based on the Wigner density formalism that allows for arbitrary phase space and multiparticle correlations. Correction terms due to intermediate state pion cascading are derived using semiclassical hadronic transport theory. Finite wave packets are used to reveal the sensitivity of pion interference effects on the details of the production dynamics. The covariant generalization of the formula is shown to be equivalent to the formula derived via an alternate current ensemble formalism for minimal wave packets and reduces in the nonrelativistic limit to a formula derived by Pratt. The final expression is ideally suited for pion interferometric tests of Monte Carlo transport models. Examples involving gaussian and inside-outside phase space distributions are considered. (orig.).

  16. Pion interferometric tests of transport models

    International Nuclear Information System (INIS)

    Padula, S.S.; Gyulassy, M.; Gavin, S.

    1990-01-01

    In hadronic reactions, the usual space-time interpretation of pion interferometry often breaks down due to strong correlations between spatial and momentum coordinates. We derive a general interferometry formula based on the Wigner density formalism that allows for arbitrary phase space and multiparticle correlations. Correction terms due to intermediate state pion cascading are derived using semiclassical hadronic transport theory. Finite wave packets are used to reveal the sensitivity of pion interference effects on the details of the production dynamics. The covariant generalization of the formula is shown to be equivalent to the formula derived via an alternate current ensemble formalism for minimal wave packets and reduces in the nonrelativistic limit to a formula derived by Pratt. The final expression is ideally suited for pion interferometric tests of Monte Carlo transport models. Examples involving gaussian and inside-outside phase space distributions are considered. (orig.)

  17. Charged pions polarizability measurement at COMPASS

    CERN Document Server

    Guskov, A

    2010-01-01

    The pion electromagnetic structure can be probed in $\\pi^{−}+(A,Z)\\rightarrow\\pi^{-}+(A,Z)+\\gamma$ Compton scattering in inverse kinematics (Primakoff reaction) and described by the electric $(\\alpha_{\\pi})$ and the magnetic $(\\beta_{\\pi})$ polarizabilities that depend on the rigidity of pion’s internal structure as a composite particle. Values for pion polarizabilities can be extracted from the comparison of the differential cross section for scattering of point-like pions with the measured cross section. The opportunity to measure pion polarizability via the Primakoff reaction at the COMPASS experiment was studied with $a$ $\\pi^{-}$ beam of 190 GeV during pilot run 2004. The obtained results were used for preparation of the new data taking which was performed in 2009.

  18. Dose measurement method suitable for management of food irradiation

    International Nuclear Information System (INIS)

    Tanaka, Ryuichi

    1990-01-01

    The report describes major features of dose measurement performed for the management of food irradiation processes, and dose measuring methods suitable for this purpose, and outlines some activities for establishing international standards for dose measurement. Traceability studies made recently are also reviewed. Compared with the sterilization of medical materials, food irradiation is different in some major points from a viewpoint of dose measurement: foods can undergo significant changes in bulk density, depending on its properties, during irradiation, and the variation in the uniformity of bulk density can be large within an irradiation unit and among different units. An accurate dosimeter and well-established traceability are essential for food irradiation control, and basically a dosimeter should be high in reproducibility and stable in dose response, and should be easy to readjust for eliminating systematic errors. A new type of dosimeter was developed recently, in which ESR is used to measure the free radicals generated by radiations in crystals of alanine, an amino acid. Standardization of large dose measurement procedures has been carried out by committee E10 set up under ASTM. (N.K.)

  19. Steam-chemical reactivity for irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, R.A.; McCarthy, K.A.; Oates, M.A.; Petti, D.A.; Pawelko, R.J.; Smolik, G.R. [Idaho National Engineering and Environmental Lab., Idaho Falls, ID (United States)

    1998-01-01

    This paper reports the results of an experimental investigation to determine the influence of neutron irradiation effects and annealing on the chemical reactivity of beryllium exposed to steam. The work entailed measurements of the H{sub 2} generation rates for unirradiated and irradiated Be and for irradiated Be that had been previously annealed at different temperatures ranging from 450degC to 1200degC. H{sub 2} generation rates were similar for irradiated and unirradiated Be in steam-chemical reactivity experiments at temperatures between 450degC and 600degC. For irradiated Be exposed to steam at 700degC, the chemical reactivity accelerated rapidly and the specimen experienced a temperature excursion. Enhanced chemical reactivity at temperatures between 400degC and 600degC was observed for irradiated Be annealed at temperatures of 700degC and higher. This reactivity enhancement could be accounted for by the increased specific surface area resulting from development of a surface-connected porosity in the irradiated-annealed Be. (author)

  20. Pion-nucleon scattering and isospin violation

    International Nuclear Information System (INIS)

    Meissner, U.G.

    1999-01-01

    The paper discusses low-energy pion-nucleon scattering in the framework of chiral perturbation theory. It is argued that using this theoretical method one is able to match the in some cases impressive experimental accuracy (for the low partial waves). It is also shown how strong and electromagnetic isospin violation can be treated simultaneously. Some first results for neutral pion scattering and the σ-term are given. Copyright (1999) World Scientific Publishing Co. Pte. Ltd

  1. Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

    International Nuclear Information System (INIS)

    Smith, Richard W.; Seymour, Colin B.; Moccia, Richard D.; Mothersill, Carmel E.

    2016-01-01

    The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent on

  2. Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Richard W., E-mail: rich.wilson.smith@gmail.com [Department of Animal Biosciences, University of Guelph, Guelph, Ontario (Canada); Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada); Seymour, Colin B. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada); Moccia, Richard D. [Department of Animal Biosciences, University of Guelph, Guelph, Ontario (Canada); Mothersill, Carmel E. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada)

    2016-02-15

    The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent on

  3. Antiquark distributions in pion and nucleon

    International Nuclear Information System (INIS)

    Arakelian, G.G.; Boreskov, K.G.; Kaidalov, A.B.

    1980-01-01

    Relation between the antiquark distributions in pion and nucleon, based on the π-exchange hypothesis, is derived. The antiquark distributions in proton are calculated with the data on the valence antiquark distribution in pion as input. Results of the calculation agree with the experimental data. The role of the peripheral mechanism in formulation of the initial conditions for the chromodynamical evolution equations is discussed

  4. HARP targets pion production cross section and yield measurements. Implications for MiniBooNE neutrino flux

    Energy Technology Data Exchange (ETDEWEB)

    Wickremasinghe, Don Athula Abeyarathna [Univ. of Cincinnati, OH (United States)

    2015-07-01

    The prediction of the muon neutrino flux from a 71.0 cm long beryllium target for the MiniBooNE experiment is based on a measured pion production cross section which was taken from a short beryllium target (2.0 cm thick - 5% nuclear interaction length) in the Hadron Production (HARP) experiment at CERN. To verify the extrapolation to our longer target, HARP also measured the pion production from 20.0 cm and 40.0 cm beryllium targets. The measured production yields, d2Nπ± (p; θ )=dpd Ω, on targets of 50% and 100% nuclear interaction lengths in the kinematic rage of momentum from 0.75 GeV/c to 6.5 GeV/c and the range of angle from 30 mrad to 210 mrad are presented along with an update of the short target cross sections. The best fitted extended Sanford-Wang (SW) model parameterization for updated short beryllium target π+ production cross section is presented. Yield measurements for all three targets are also compared with that from the Monte Carlo predictions in the MiniBooNE experiment for different SW parameterization. The comparisons of vμ flux predictions for updated SW model is presented.

  5. Application of Irradiation. Application to polymer processing, exhaust gas treatment, sterilization of medical instruments and food

    Energy Technology Data Exchange (ETDEWEB)

    Sawai, Takeshi; Sawai, Teruko

    2000-03-01

    Many fields such as industry, agriculture, medical treatment and environment use radiation. This report explained some examples of irradiation applications. Radiation source is {sup 60}Co {gamma}-ray. Polymer industry use radiation for radiation curing (thermally stable polymer), tire, expanded polymer, radiation induced graft copolymerization and electron beam curing. On environmental conservation, radiation is used for elimination of NOx and SOx in exhaust combustion gas. In the medical treatment, radiation is applied to sterilization of medical instruments, that occupied about 50% volume, and blood for transfusion, which is only one method to prevent GVHD after transfusion. On agriculture, irradiation to spice, dry vegetable, frozen kitchen, potato and garlic are carried out in 30 countries. However, potato is only a kind food in Japan. Radiation breeding and pest control are put in practice. (S.Y.)

  6. A Unified approach for nucleon knock-out, coherent and incoherent pion production in neutrino interactions with nuclei

    CERN Document Server

    Martini, M.; Chanfray, G.; Marteau, J.

    2009-01-01

    We present a theory of neutrino interactions with nuclei aimed at the description of the partial cross-sections, namely quasi-elastic and multi-nucleon emission, coherent and incoherent single pion production. For this purpose, we use the theory of nuclear responses treated in the random phase approximation, which allows a unified description of these channels. It is particularly suited for the coherent pion production where collective effects are important whereas they are moderate in the other channels. We also study the evolution of the neutrino cross-sections with the mass number from carbon to calcium. We compare our approach to the available neutrino experimental data on carbon. We put a particular emphasis on the multi-nucleon channel, which at present is not easily distinguishable from the quasi-elastic events. This component turns out to be quite relevant for the interpretation of experiments (K2K, MiniBooNE, SciBooNE). It can account in particular for the unexpected behavior of the quasi-elastic cro...

  7. OPEM3-program for calculating pion differential spectra in pp → npπ+ reaction at energies up to 1 GeV. Physical model

    International Nuclear Information System (INIS)

    Suslenko, V.K.; Gajsak, I.I.

    1982-01-01

    Theoretical basis for the program to calcUlate the denSjties of differential criss sections of the third order (spectra) for pions produced in the reaction pp → npπ + at enerajes up to 1 GeV is presented. A variant of one pion exchange model (OPEM), im which precise account of all contributions from four polar Feynman diagrams is made is selected as a a physical model of the reaction pp → npπ + . The model apparatus is presented in correspondence with the scheme of the structure of OPEM 3 program for computer realized in Fortran language

  8. Studies of the effect of irradiation in a nuclear reactor, of targets containing Mo used for the preparation of 99Mo gel, material that constitutes the 99Mo - 99mTc generators

    International Nuclear Information System (INIS)

    Nieto, Renata Correa

    2004-01-01

    The most used radioisotope in Nuclear Medicine is 99m Tc, obtained in the 99 Mo - 99m Tc generator form. 99 Mo can be produced by several nuclear reactions in Cyclotron and Reactor. The production in Cyclotron is not technically and commercially feasible. The production in Nuclear Reactor can be made in two ways: 235 U fission and 99 Mo (n,γ) 99 Mo reaction. A project aiming the production of 99 Mo by activation of Mo is under way at IPEN, producing a gel type MoZr generator. There are two ways of preparing the gel and the generators: by irradiating MoO 3 and preparing the gel or by the preparation of the gel and further irradiation. This work consists in the study of the irradiation effects in several targets containing Mo for the production of 99 Mo by the 98 Mo (n,γ) 99 Mo reaction and further preparation of the gel for use as a gel type 99 Mo - 99m Tc generator. Three rinds of gel were studied: zirconium, titanium and cerium molybdate, and their morphology, infrared structure and elution yield of 99m Tc were analysed. The best results were achieved with the generators prepared with MoZr post formed gel, with amorphous structure and better elution yields. The pre formed gel induced crystallinity and worst performance of the generators. (author)

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

    International Nuclear Information System (INIS)

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

    1993-01-01

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

  10. Measurements of longitudinal and transverse momentum distributions for neutral pions in the forward-rapidity region with the LHCf detector

    CERN Document Server

    Adriani, O.; Bonechi, L.; Bongi, M.; D'Alessandro, R.; Del Prete, M.; Haguenauer, M.; Itow, Y.; Kasahara, K.; Kawade, K.; Makino, Y.; Masuda, K.; Matsubayashi, E.; Menjo, H.; Mitsuka, G.; Muraki, Y.; Papini, P.; Perrot, A.L.; Ricciarini, S.; Sako, T.; Sakurai, N.; Suzuki, T.; Tamura, T.; Tiberio, A.; Torii, S.; Tricomi, A.; Turner, W.C.; Zhou, Q.D.

    2016-01-01

    The transverse and longitudinal momentum distributions for inclusive neutral pions in the very forward rapidity region have been measured with the Large Hadron Collider forward detector in proton-proton collisions at $\\sqrt{s}=$ 2.76 and 7 TeV and in proton-lead collisions at nucleon-nucleon center-of-mass energies of $\\sqrt{s_\\text{NN}}=$ 5.02 TeV at the LHC. Such momentum distributions in proton-proton collisions are compatible with the hypotheses of limiting fragmentation and Feynman scaling. A sizable suppression of the production of neutral pions, after taking into account ultraperipheral collisions, is found in the transverse and longitudinal momentum distributions obtained in proton-lead collisions. This leads to a strong nuclear modification factor value of about 0.1-0.3. The experimental measurements presented in this paper provide a benchmark for the hadronic interaction Monte Carlo simulations codes that are used for the simulation of air showers.

  11. Nuclear-medical irradiation during pregnancy. Risk assessment for the offspring; Nuklearmedizinische Strahlenexpositionen waehrend der Schwangerschaft. Risikoabschaetzungen fuer die Leibesfrucht

    Energy Technology Data Exchange (ETDEWEB)

    Minkov, V.; Nekolla, E.A.; Nosske, D.; Griebel, J.; Brix, G. [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Abt. fuer Medizinische Strahlenhygiene und Dosimetrie

    2009-07-01

    To estimate and evaluate the risks for the offspring due to the administration of radiopharmaceuticals to women during the first pregnancy weeks after conception (weeks p.c.). The in-utero exposition of the embryo due to diagnostic nuclear medicine procedures, for which diagnostic reference levels (DRL) are specified, as well as due to radio iodine therapy (RIT) was determined. To this end, it is assumed that the activity of the diagnostic radiopharmaceuticals administered to the mother corresponds with the DRL and amounts to 600 MBq or 4 GBq {sup 131}I for RIT of benign or malignant thyroid disease, respectively. Based on these data, the radiation risk for the offspring was assessed and compared with the spontaneous risks (R{sub 0}). The dose for the offspring does not exceed 7.8 mSv for the diagnostic procedures considered, resulting in an excess risk for the offspring of less than 0.12% (R{sub 0} {proportional_to} 25%) to die from cancer during life, of less than 0.07% (R{sub 0} {proportional_to} 0.2%) to develop cancer up to the age of 15 years, and of less than 0.16% (R{sub 0} {proportional_to} 2%) for hereditary effects. RIT during the first 8 weeks p.c. results in doses for the offspring of about 100-460 mSv, resulting in an excess risk for malformations of the child of 3.4%-22% (R{sub 0} {proportional_to}6%). The risk of stochastic radiation effects for the offspring due to a diagnostic nuclear medicine procedure of the mother during the first 8 weeks p.c. is - compared with the spontaneous risks - very small; deterministic effects are unlikely. In contrast, deterministic effects for the offspring may occur following RIT. In order to decide on a possibly indicated abortion after RIT, an individual risk assessment is mandatory. (orig.)

  12. Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish.

    Science.gov (United States)

    Smith, Richard W; Seymour, Colin B; Moccia, Richard D; Mothersill, Carmel E

    2016-02-01

    The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Development of a user-friendly system for image processing of electron microscopy by integrating a web browser and PIONE with Eos.

    Science.gov (United States)

    Tsukamoto, Takafumi; Yasunaga, Takuo

    2014-11-01

    need to provide common workspace for analysis because the client is physically separated from a server. We solved the file format problem by extension of rules of OptionControlFile of Eos. Furthermore, to solve workspace problems, we have developed two type of system. The first system is to use only local environments. The user runs a web server provided by Eos, access to a web client through a web browser, and manipulate the local files with GUI on the web browser. The second system is employing PIONE (Process-rule for Input/Output Negotiation Environment), which is our developing platform that works under heterogenic distributed environment. The users can put their resources, such as microscopic images, text files and so on, into the server-side environment supported by PIONE, and so experts can write PIONE rule definition, which defines a workflow of image processing. PIONE run each image processing on suitable computers, following the defined rule. PIONE has the ability of interactive manipulation, and user is able to try a command with various setting values. In this situation, we contribute to auto-generation of GUI for a PIONE workflow.As advanced functions, we have developed a module to log user actions. The logs include information such as setting values in image processing, procedure of commands and so on. If we use the logs effectively, we can get a lot of advantages. For example, when an expert may discover some know-how of image processing, other users can also share logs including his know-hows and so we may obtain recommendation workflow of image analysis, if we analyze logs. To implement social platform of image processing for electron microscopists, we have developed system infrastructure, as well. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. The pseudo-scalar form factor of the nucleon, the sigma-like term, and the L0+ amplitude for charged pion electro-production near threshold

    International Nuclear Information System (INIS)

    Cheoun, Myung Ki; Kim, K.S.

    2007-01-01

    The pseudo-scalar form factor, which represents the pseudo-scalar quark density distribution due to finite quark masses on the nucleon, is shown to manifest itself with the induced pseudo-scalar form factor in the L 0 + amplitude for the charged pion electro-production. Both form factors show their own peculiar momentum dependence. Under the approximation on which the Goldberger-Treiman relation holds, a sum of both form factors' contributions accounts for the t-channel contribution in the charged pion electro-production near threshold

  15. Interaction of slow pions with atomic nuclei

    International Nuclear Information System (INIS)

    Troitskij, M.A.; Tsybul'nikov, A.V.; Chekunaev, N.I.

    1984-01-01

    Interactions of slow pions with atomic nuclei near to pion condensation are investigated. From comparison of experimental data with the theoretical calculation results on the basis of precise microscopic approach not bound with the random phase approximation (RPA) nuclear matter fundamental parameters near a critical point can be found. Optical potential of slow pions in nuclei, πN-scattering amplitudes and lengths, π-atom level isotopic shift, phenomenon of single-nucleon pion absorption by nucleus, phenomenon of nuclear critical opalescence are considered. The results of πN-scattering lengths calculation, sup(40-44)Ca, sup(24-29)Mg, sup(16-18)O π-atom level shift are presented. It is shown that the presence of π-condensate in nuclei can explain the observed suppression of p-wave potential terms. The phenomenon of single-nucleon pion absorption by nucleus is one of direct experiments which permits to reveal the π-condensate. The nuclear opalescence phenomenon is manifested in increase of pion photoproduction reaction cross section for account of nucleus proximity to π-condensation as compared with the calculated in the Fermi-gas model. The suggested method for calculating precondensate phenomena operates the better, the nearer is the system to the condensation threshold whereas the RPA method in this region is inapplicable

  16. Model of the contribution of the compton generated radiation to the dose rate for an experiment in a semi industrial irradiation plant

    International Nuclear Information System (INIS)

    Mangussi, Josefina

    2007-01-01

    The model of the build up contribution to the absorbed dose rate in a semi industrial irradiation plant is presented. A static irradiation of a lucite phantom with and without water is modeled. The absorbed dose was measured with silver and potassium dichromate dosemeters. Two approximations are used, the first one is a global adjustment of the attenuation coefficient and the second one consists in a detailed description of the Compton scattering. A specific numerical model is developed for each approximation and the absorbed dose rates calculated are compared with the experimental measurements. The achievements and limitations of both models are discussed. (author) [es

  17. Irradiation can for the activation of materials in nuclear reactors

    International Nuclear Information System (INIS)

    Schneider, B.; Findeisen, A.; Katzmann, H.

    1985-01-01

    The invention is concerning with an irradiation can for the activation of materials in nuclear reactors in particular for materials with a high heat generation due to irradiation. A good heat transfer between the irradiated material and the irradiation can environment has been guaranteed by a special can design. The outside of the can consists of a tube or a tube bandle which has been formed as a water guide tube. One or more tubes containing the irradiated materials have been positioned at the inner areas of the irradiated can

  18. Irradiance sensors for solar systems

    Energy Technology Data Exchange (ETDEWEB)

    Storch, A.; Schindl, J. [Oesterreichisches Forschungs- und Pruefzentrum Arsenal GesmbH, Vienna (Austria). Business Unit Renewable Energy

    2004-07-01

    The presented project surveyed the quality of irradiance sensors used for applications in solar systems. By analysing an outdoor measurement, the accuracies of ten commercially available irradiance sensors were evaluated, comparing their results to those of a calibrated Kipp and Zonen pyranometer CM21. Furthermore, as a simple method for improving the quality of the results, for each sensor an irradiance-calibration was carried out and examined for its effectiveness. (orig.)

  19. Reverse indentation size effects in gamma irradiated blood compatible blend films of chitosan-poly (vinyl alcohol) for possible medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Bisen, D.S. [Department of Post Graduate Studies and Research in Physics, Rani Durgawati University, Jabalpur, M.P. 482002 (India); Bhatt, Rinkesh [Department of Physics, Global Engineering College, Jabalpur, M.P. 482001 (India); Bajpai, A.K., E-mail: akbmrl@yahoo.co.in [Department of Chemistry, Bose Memorial Research Lab., Govt. Auto. Model Science College, Jabalpur 482002, M.P. (India); Bajpai, R. [Department of Post Graduate Studies and Research in Physics, Rani Durgawati University, Jabalpur, M.P. 482002 (India); Katare, R. [Department of Physics, Government Model Science College, Jabalpur, M.P. 482001 (India)

    2017-02-01

    In the present work binary blends of polyvinyl alcohol (PVA) and chitosan (CS) were prepared by solution cast method and characterized by analytical methods like FTIR, XRD and SEM for seeking structural and morphological information. The blends were exposed to gamma radiation and evaluated for their improved mechanical strength. It was found that the tensile strength and microhardness increased after irradiation of CS-PVA films. Plastic effect due to absorption of water molecules and scissoring effect due to gamma irradiation were found to decrease the softness or increase the microhardness of the blends. Improved mechanical properties were attributed to intermolecular and intramolecular hydrogen bonds and adhesive nature of the blends also. The blends were also investigated for water intake behavior and in vitro blood compatibility property on the basis of certain in vitro tests like protein adsorption, haemolysis and blood clot formation on the un-irradiated and irradiated blend samples. The increased % swelling with time could be assigned to the fact that increasing water content facilitates the phase separation process within the blend which results in advancement in interstitial nano-void spaces which are occupied by water molecules. The blood compatibility results showed that when the amount of CS was varied from 0.5% to 2%, the amount of blood clot and percent haemolysis decreased while the protein adsorption increased with increasing CS content of the blend films. - Highlights: • Fully crosslinked blends of PVA and chitosan have been prepared. • Blends were irradiated with gamma radiations to enhance blood compatibility. • Mechanical properties were evaluated and effect of irradiation was examined. • The blood compatibility of blends was also determined.

  20. Reverse indentation size effects in gamma irradiated blood compatible blend films of chitosan-poly (vinyl alcohol) for possible medical applications

    International Nuclear Information System (INIS)

    Bisen, D.S.; Bhatt, Rinkesh; Bajpai, A.K.; Bajpai, R.; Katare, R.

    2017-01-01

    In the present work binary blends of polyvinyl alcohol (PVA) and chitosan (CS) were prepared by solution cast method and characterized by analytical methods like FTIR, XRD and SEM for seeking structural and morphological information. The blends were exposed to gamma radiation and evaluated for their improved mechanical strength. It was found that the tensile strength and microhardness increased after irradiation of CS-PVA films. Plastic effect due to absorption of water molecules and scissoring effect due to gamma irradiation were found to decrease the softness or increase the microhardness of the blends. Improved mechanical properties were attributed to intermolecular and intramolecular hydrogen bonds and adhesive nature of the blends also. The blends were also investigated for water intake behavior and in vitro blood compatibility property on the basis of certain in vitro tests like protein adsorption, haemolysis and blood clot formation on the un-irradiated and irradiated blend samples. The increased % swelling with time could be assigned to the fact that increasing water content facilitates the phase separation process within the blend which results in advancement in interstitial nano-void spaces which are occupied by water molecules. The blood compatibility results showed that when the amount of CS was varied from 0.5% to 2%, the amount of blood clot and percent haemolysis decreased while the protein adsorption increased with increasing CS content of the blend films. - Highlights: • Fully crosslinked blends of PVA and chitosan have been prepared. • Blends were irradiated with gamma radiations to enhance blood compatibility. • Mechanical properties were evaluated and effect of irradiation was examined. • The blood compatibility of blends was also determined.

  1. Goldstone pion and other mesons using a scalar confining interaction

    International Nuclear Information System (INIS)

    Gross, F.; Milana, J.

    1994-01-01

    A covariant wave equation for q bar q interactions with an interaction kernel composed of the sum of constant vector and linear scalar confining interactions is solved for states with two quarks with identical mass. The model includes an NJL-like mechanism which links the dynamical breaking of chiral symmetry to the spontaneous generation of quark mass and the appearance of a low mass Goldstone pion. A novel feature of this approach is that it automatically explains the small mass of the pion even though the linear potential is a scalar interaction in Dirac space, and hence breaks chiral symmetry. Solutions for mesons composed of light quarks (π,ρ, and low lying excited states) and heavy quarks (ρ c , J/Ψ, and low lying excited states) are presented and discussed

  2. Search for CP violation in the decay of the D meson into three pions using the LHCb detector

    Energy Technology Data Exchange (ETDEWEB)

    Amato, Sandra; Polycarpo, Erica; Vieira, Daniel [Universidade Federal do Rio de Janeiro (LAPE/IF/UFRJ), RJ (Brazil). Inst. de Fisica. Lab. de Particulas Elementares; Goebel, Carla; Molina, Josue [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil); Reis, Alberto [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Full text: LHCb is the only LHC (Large Hadron Collider) experiment that has as main purpose the study of charge parity (CP) symmetry violation phenomena in the decays of heavy flavors. CP violation is related to the matter and antimatter asymmetry in the universe. It is known, however, that the magnitude of the asymmetry as predicted by the Standard Model (SM) is not enough to explain the one observed, suggesting that there must be new sources of CP violation. Here, we present the status of our search for CP violation in the decay of the D meson into three pions, a challenging channel due to the high level of background events. The Standard Model predictions indicate very small effects - asymmetries not greater than 0.1 %. However, new physics effects could be as large as 1%, which makes the search for CP violation in this sector an attractive problem. This analysis is based on the comparison of the D{sup +} and D{sup -} distributions across the Dalitz Plot using the anisotropy method. The distribution of the statistical significance of the difference between the number of D{sup +} {yields} {pi}{sup -}{pi}{sup +}{pi}{sup +} and D{sup {yields}} {pi}{sup +}{pi}{sup -}{pi}{sup -} decays on the different two-dimensional bins of the Dalitz Plot surface should be compatible with a Gaussian distribution of width equal to 1 and mean value equal to 0, in the absence of CPV. Deviations from this pattern indicate CP violation. We determine the sensitivity of this method using toy MC studies, where we can generate D meson decays with CP asymmetries in the phases or in the magnitudes of the amplitudes contributing to the process. Possible systematic effects are investigated using control channels with similar topology, which would show the same kind of possible instrumental asymmetries and are not expected to present true CP violation. Once the method is shown to work, i.e., not to introduce any fake CP asymmetry and to be sensitive to possible CPV effects, we can apply it to

  3. Irradiated food for immunocompromised people

    International Nuclear Information System (INIS)

    Narvaiz, Patricia

    2005-01-01

    Immune-compromise is a condition in which the natural defenses against diseases are dimished; several situations can be cited as examples, including mis nourishment, pregnancy, young and old age. This enhances the probability of suffering microbial diseases, caused by food borne pathogens. Traditionally, immune-suppressed patients in hospitals were isolated from the environment, being their food sterilized by different treatments, including irradiation. At present the medical opinion differs from this approach due to the costs and specialized requirements, uncertainties about the clinical benefits, and psychological convenience. So, the tendency nowadays seems to move, when the patient's condition allows it, from 'sterile diets' to 'low microbe diets' (or 'clean diets'). At the National Atomic Energy Commission, Argentina, under Coordinated Research Programmes of the Food and Environmental Preservation Section, International Atomic Energy Agency, in which 14 countries participated, treatments at pasteurizing doses were studied to widen the meals availability for vulnerable persons, to include some products usually considered as 'high risk' , but nutritionally or psychologically adequate. In a first experience, nutritionists working at the corresponding Service in a Buenos Aires hospital elaborated diets suitable for patients with different immune-compromise degrees, and advised on the interesting meal types to be studied. In a second experience, advanced nutrition students of the Entre Rios University performed a sensory evaluation in which 44 immune- compromised patients at the Jose de San Martin Clinical School Hospital, Buenos Aires, tasted a whole irradiated lunch composed of meals usually forbidden due to high microbial risk, though highly desired. The patients evaluated this lunch with high scores and showed enthusiastic towards the irradiation treatment. This preservation treatment could not only be useful to supply hospitals but also supermarkets. (author)

  4. Identification of irradiated foods prospects for post-irradiation estimate of irradiation dose in irradiated dry egg products

    International Nuclear Information System (INIS)

    Katusin-Raxem, B.; Mihaljievic, B.; Razem, D.

    2002-01-01

    estimation of the original irradiation dose. Alternative methods of generation of LOOH in egg powder were investigated, as well as possible methods of destroying it after irradiation. Keeping egg powder at an elevated temperature for an extended period of time or boiling in water proved unsuccessful in either generating or destroying detectable LOOH

  5. A Low-Power Medical Oxygen Generator, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — An on-board oxygen concentrator is required during long duration manned space missions to supply medical oxygen. The commercial medical oxygen generators based on...

  6. A Low-Power Medical Oxygen Generator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An on-board oxygen concentrator is required during long duration manned space missions to supply medical oxygen. The commercial medical oxygen generators based on...

  7. Measurement of the charged-pion polarisability at COMPASS

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    For more than a decade, COMPASS has been tackling the measurement of the electromagnetic polarizability of the charged pion, which describes the stiffness of the pion against deformation in electromagnetic fields. Previous experiments date back to the 1980's in Serpukhov (Russia), where the Primakoff method for realizing interactions of charged pions with quasi-real photons was first employed. Later also other techniques in photon-nucleon and photon-photon collisions were carried out at different machines. The COMPASS measurement demonstrates that the charged-pion polarizability is significantly smaller than the previous results, roughly by a factor two, with the smallest uncertainties realized so far. The pion polarisability is of fundamental interest in the low-energy sector of quantum chromodynamics. It is directly linked to the quark-gluon substructure and dynamics of the pion, the lightest bound system of strong interaction.

  8. Low energy pion detection by a silicon surface barrier telescope

    International Nuclear Information System (INIS)

    Sealock, R.M.; Caplan, H.S.; Leung, M.K.

    1978-01-01

    Four telescopes of three (2-ΔE, 1-E) silicon surface barrier detectors each, mounted in the focal plane of a magnetic spectrometer, have been used to detect positive pions in the energy range from 4.7-17.9 MeV and negative pions from 14.1-17.9 MeV. Positive pions from 4.7-12.7 MeV were stopped in the third detector while positive and negative pions from 14.1-17.9 MeV were detected in transmission. For energies greater than 7.4 MeV aluminum moderators were placed in front of the first detector to degrade the pion energy. Energy spectra show well resolved pion peaks with extremely low background. Double differential cross sections for the 12 C(e,π + ) 12 B,e' reaction have been measured. (Auth.)

  9. Tube for irradiation equipment

    International Nuclear Information System (INIS)

    Goehrich, K.; Vogt, H.

    1979-01-01

    This patent describes a tube for irradiation equipment for limiting an emergent beam, with a baseplate, possessing a central aperture, intended for attaching to the equipment, as well as four carrier plates, each of which possesses a limiting edge and a sliding edge located at right angles thereto. The carrier plates are located parallel to the baseplate, the limiting edge of each carrier plate resting against the sliding edge of the adjacent carrier plate and each of the two mutually opposite pairs of carrier plates being displaceable, parallel to the direction of its sliding edges and symmetrically to the center of the transmission aperture, for the purpose of continuously varying the transmission aperture defined by the limiting edges, during which displacement each of the displaced carrier plates carries with it the carrier plate, resting against the limiting edge of the former plate, parallel to the direction of the limiting edge of the latter plate. 8 claims

  10. Pion scattering and nuclear dynamics

    International Nuclear Information System (INIS)

    Johnson, M.B.

    1988-01-01

    A phenomenological optical-model analysis of pion elastic scattering and single- and double-charge-exchange scattering to isobaric-analog states is reviewed. Interpretation of the optical-model parameters is briefly discussed, and several applications and extensions are considered. The applications include the study of various nuclear properties, including neutron deformation and surface-fluctuation contributions to the density. One promising extension for the near future would be to develop a microscopic approach based on powerful momentum-space methods brought to existence over the last decade. In this, the lowest-order optical potential as well as specific higher-order pieces would be worked out in terms of microscopic pion-nucleon and delta-nucleon interactions that can be determined within modern meson-theoretical frameworks. A second extension, of a more phenomenological nature, would use coupled-channel methods and shell-model wave functions to study dynamical nuclear correlations in pion double charge exchange. 35 refs., 11 figs., 1 tab

  11. Pion condensation and instabilities: current theory and experiment

    International Nuclear Information System (INIS)

    Gyulassy, M.

    1980-05-01

    Current calculations of pion condensation phenomena in symmetric nuclear matter are reviewed. The RPA and MFA methods are compared. Latest results [LBL-10572] with a relativistic MFA theory constrained by bulk nuclear properties are presented. The differences between equilibrium (condensation) and nonequilibrium (dynamic) instabilities are discussed. Finally, two-proton correlation experiments aimed at looking for critical scattering phenomena and two-pion correlation experiments aimed at looking for pion field coherence are analyzed. 10 figures, 2 tables

  12. Effect of gamma irradiation in the pupal stage on the fall armyworm parent and F1 generations reproduction

    International Nuclear Information System (INIS)

    Arthur, V.; Wiendl, F.M.; Duarte-Aguilar, J.A.; Wiendl, J.A.

    1994-01-01

    To induce sterilization into F 1 generation, pupae of the fall armyworm Spodoptera frugiperda (Smith, 1797) (Lepidoptera, Noctuidae) were irradiated at the age of five days. The radiation source was a Cobalt-60 panoramic irradiator. The pupae were irradiated at the dose-rate of 2.60 kGy/h with doses of 0 (control), 50, 75, 100 and 125 Gy. The hatching of the eggs laid by the adults originated from the irradiated pupae with dose of 125 Gy were 15.0 and 10.0 percent for males and females respectively. Crossing this irradiated parent generation, it could be found that the F 1 generation reached 93.0 percent of hatching for both sexes

  13. Container for irradiated fuel

    International Nuclear Information System (INIS)

    Guy, R.

    1978-01-01

    The transport container for irradiated or used nuclear fuel is provided with an identical heat shield against fires on the top and bottom sides. Each heat shield consists of two inner nickel plates, whose contact surfaces are polished to a mirror finish and an outer plate of stainless steel. The nickel plate on the box is spot welded to it while the second nickel plate is spot welded to the steel plate. Both together are in turn welded so as to be leaktight to the edges of the box. For extreme heat effects and based on the different (bimetal) coefficients of expansion, the steel plate with the nickel plate attached to it bulges away from the box. The second nickel plate remains at the box, so that a subpressure space is formed with the mirror nickel surfaces. The heat radiation and heat conduction to the box are greatly reduced by this. (DG) [de

  14. Characteristic aspects of pion-condensed phases

    International Nuclear Information System (INIS)

    Takatsuka, Tatsuyuki; Tamagaki, Ryozo; Tatsumi, Toshitaka.

    1993-01-01

    Characteristic aspects of pion-condensed phases are described in a simple model, for the system involving only nucleons and pions which interact through the π-N P-wave interaction. We consider one typical version in each of three kinds of pion condensation; the one of neutral pions (π 0 ), the one of charged pions (π C ) and the combined one in which both the π 0 and π C condensations are coexistent. Emphasis is put on the description to clarify the novel structures of the nucleon system which are realized in the pion-condensed phases. At first, it is shown that the π 0 condensation is equivalent to the particular nucleonic phase realized by a structure change of the nucleon system, where the attractive first-order effect of the one-pion-exchange (OPE) tensor force is brought about coherently. The aspects of this phase are characterized by the layered structure with a specific spin-isospin order with one-dimensional localization (named the ALS structure in short), which provides the source function for the condensed π 0 field. We utilize both descriptions with use of fields and potentials for the π 0 condensation. Next, the π C condensation realized in neutron-rich matter is described by adopting a version of the traveling condensed wave. In this phase, the nucleonic structure becomes the Fermi gas consisting of quasi-neutrons described by a superposition of neutron and proton. In this sense the structure change of the nucleon system for the π C condensation is moderate, and the field description is suitable. Finally, we describe a coexistent pion condensation, in which both the π 0 and π C condensations coexist without interference in such a manner that the π C condensation develops in the ALS structure. The model adopted here provides us with the characteristic aspects of the pion-condensed phases persisting in the realistic situation, where other ingredients affecting the pion condensation are taken into account. (author)

  15. [Measurements of observables of pion-nucleon reactions]. Progress report

    International Nuclear Information System (INIS)

    Sadler, M.E.

    1985-01-01

    This document reports the progress of the research of pion reactions. These include (1) a study to measure observables in the pion-nucleon system in the momentum interval 400 to 700 MeV/c, (2) differential cross section measurements at low energy for pion-nucleon charge exchange, and (3) elastic and inelastic scattering of π +- on 3 H and 3 He. Individual experiments will be indexed separately

  16. A possible form of the pion's structure function

    International Nuclear Information System (INIS)

    Long Ming; Huang Tao

    1986-01-01

    The pion's structure function behaviour is discussed by using the Fock state expansion of the hadronic wave function in QCD in this paper. As an example, we employ a model wave function of the Fock state in the light-cone and assume a Regge behaviour of a weight function for higher Fock states, and we get a possible form of the pion's structure function. This form is consistent with experimental data of the pion's structure function

  17. Genetic Programming for the Generation of Crisp and Fuzzy Rule Bases in Classification and Diagnosis of Medical Data

    DEFF Research Database (Denmark)

    Dounias, George; Tsakonas, Athanasios; Jantzen, Jan

    2002-01-01

    This paper demonstrates two methodologies for the construction of rule-based systems in medical decision making. The first approach consists of a method combining genetic programming and heuristic hierarchical rule-base construction. The second model is composed by a strongly-typed genetic...

  18. Nanoparticle production by UV irradiation of combustion generated soot particles

    International Nuclear Information System (INIS)

    Stipe, Christopher B.; Choi, Jong Hyun; Lucas, Donald; Koshland, Catherine P.; Sawyer, Robert F.

    2004-01-01

    Laser ablation of surfaces normally produce high temperature plasmas that are difficult to control. By irradiating small particles in the gas phase, we can better control the size and concentration of the resulting particles when different materials are photofragmented. Here, we irradiate soot with 193 nm light from an ArF excimer laser. Irradiating the original agglomerated particles at fluences ranging from 0.07 to 0.26 J/cm 2 with repetition rates of 20 and 100 Hz produces a large number of small, unagglomerated particles, and a smaller number of spherical agglomerated particles. Mean particle diameters from 20 to 50 nm are produced from soot originally having a mean electric mobility diameter of 265nm. We use a non-dimensional parameter, called the photon/atom ratio (PAR), to aid in understanding the photofragmentation process. This parameter is the ratio of the number of photons striking the soot particles to the number of the carbon atoms contained in the soot particles, and is a better metric than the laser fluence for analyzing laser-particle interactions. These results suggest that UV photofragmentation can be effective in controlling particle size and morphology, and can be a useful diagnostic for studying elements of the laser ablation process

  19. Dose rate on the environment generated by a gamma irradiation plant

    International Nuclear Information System (INIS)

    Mangussi, J.

    2011-01-01

    A model for the absorbed dose rate calculation on the surroundings of a gamma irradiation plant is developed. In such plants, a part of the radiation emitted upwards reach the outdoors. The Compton scatterings on the wall of the exhausting pipes through de plant roof and on the outdoors air are modelled. The absorbed dose rate generated by the scattered radiation reaching the outdoors floor is calculated. The results of the models, to be used for the irradiation plant design and for the environmental studies, are showed on tables and graphics. (author) [es

  20. Lateral propagation of MeV electrons generated by femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Seely, J. F.; Szabo, C. I.; Audebert, P.; Brambrink, E.; Tabakhoff, E.; Hudson, L. T.

    2010-01-01

    The propagation of MeV electrons generated by intense (≅10 20 W/cm 2 ) femtosecond laser irradiation, in the lateral direction perpendicular to the incident laser beam, was studied using targets consisting of irradiated metal wires and neighboring spectator wires embedded in electrically conductive (aluminum) or resistive (Teflon) substrates. The K shell spectra in the energy range 40-60 keV from wires of Gd, Dy, Hf, and W were recorded by a transmission crystal spectrometer. The spectra were produced by 1s electron ionization in the irradiated wire and by energetic electron propagation through the substrate material to the spectator wire of a different metal. The electron range and energy were determined from the relative K shell emissions from the irradiated and spectator wires separated by varying substrate lateral distances of up to 1 mm. It was found that electron propagation through Teflon was inhibited, compared to aluminum, implying a relatively weak return current and incomplete space-charge neutralization. The energetic electron propagation in the direction parallel to the electric field of the laser beam was larger than perpendicular to the electric field. Energetic electron production was lower when directly irradiating aluminum or Teflon compared to irradiating the heavy metal wires. These experiments are important for the determination of the energetic electron production mechanism and for understanding lateral electron propagation that can be detrimental to fast-ignition fusion and hard x-ray backlighter radiography.

  1. DWPI: a computer program to calculate the inelastic scattering of pions from nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Eisenstein, R A; Miller, G A [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics

    1976-02-01

    Angular distributions for the inelastic scattering of pions are generated using the distorted wave impulse approximation (DWIA). The cross section for a given transition is calculated by summing a partial wave expansion. The T-matrix elements are calculated using distorted pion waves from the program PIRK, and therefore include elastic scattering to all orders. The excitation is treated in first order only. Several optical potentials and nuclear densities are available in the program. The transition form factor may be uncoupled from the ground-state density. Coulomb excitation, which interferes coherently with the strong interaction, is a program option.

  2. Irradiation for xenogeneic transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Halperin, E.C.; Knechtle, S.J.; Harland, R.C.; Yamaguchi, Yasua; Sontag, M.; Bollinger, R.R. (Duke Univ., Durham, NC (USA). Dept. of Radiology Duke Univ., Durham, NC (USA). Dept. of Microbiology and Immunology)

    1990-05-01

    Xenogeneic transplantation (XT) is the transplantation of organs or tissues from a member of one species to a member of another. Mammalian species frequently have circulating antibody which is directed against the foreign organ irrespective of known prior antigen exposure. This antibody may lead to hyperacute rejection once it ensues so efforts must be directed towards eliminating the pre-existing antibody. In those species in which hyperacute rejection of xenografts does not occur, cell-mediated refection, similar to allograft rejection, may occur. It is in the prevention of this latter form of refection that radiation is most likely to be beneficial in XT. Both total lymphoid irradiation (TLI) and selective lyphoid irradiation (LSI) have been investigated for use in conjunction with XT. TLI has contributed to the prolongation of pancreatic islet-cell xenografts from hamsters to rats. TLI has also markedly prolonged the survival of cardiac transplants from hamsters to rats. A more modest prolongation of graft survival has been seen with the use of TLI in rabbit-to-rat exchanges. Therapy with TLI, cyclosporine, and splenectomy has markedly prolonged the survival of liver transplants from hamsters to rats, and preliminary data suggest that TLI may contribute to the prolongation of graft survival in the transplantation of hearts from monkeys to baboons. SLI appears to have prolonged graft survival, when used in conjunction with anti-lymphocyte globulin, in hamster-to-rat cardiac graft exchanges. The current state of knowledge of the use of irradiaiton in experimental XT is reviewed. (author). 38 refs.; 1 fig.; 5 tabs.

  3. Irradiation for xenogeneic transplantation

    International Nuclear Information System (INIS)

    Halperin, E.C.; Knechtle, S.J.; Harland, R.C.; Yamaguchi, Yasua; Sontag, M.; Bollinger, R.R.; Duke Univ., Durham, NC

    1990-01-01

    Xenogeneic transplantation (XT) is the transplantation of organs or tissues from a member of one species to a member of another. Mammalian species frequently have circulating antibody which is directed against the foreign organ irrespective of known prior antigen exposure. This antibody may lead to hyperacute rejection once it ensues so efforts must be directed towards eliminating the pre-existing antibody. In those species in which hyperacute rejection of xenografts does not occur, cell-mediated refection, similar to allograft rejection, may occur. It is in the prevention of this latter form of refection that radiation is most likely to be beneficial in XT. Both total lymphoid irradiation (TLI) and selective lyphoid irradiation (LSI) have been investigated for use in conjunction with XT. TLI has contributed to the prolongation of pancreatic islet-cell xenografts from hamsters to rats. TLI has also markedly prolonged the survival of cardiac transplants from hamsters to rats. A more modest prolongation of graft survival has been seen with the use of TLI in rabbit-to-rat exchanges. Therapy with TLI, cyclosporine, and splenectomy has markedly prolonged the survival of liver transplants from hamsters to rats, and preliminary data suggest that TLI may contribute to the prolongation of graft survival in the transplantation of hearts from monkeys to baboons. SLI appears to have prolonged graft survival, when used in conjunction with anti-lymphocyte globulin, in hamster-to-rat cardiac graft exchanges. The current state of knowledge of the use of irradiaiton in experimental XT is reviewed. (author). 38 refs.; 1 fig.; 5 tabs

  4. Uranium briquettes for irradiation target

    Energy Technology Data Exchange (ETDEWEB)

    Saliba-Silva, Adonis Marcelo; Garcia, Rafael Henrique Lazzari; Martins, Ilson Carlos; Carvalho, Elita Fontenele Urano de; Durazzo, Michelangelo, E-mail: saliba@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Direct irradiation on targets inside nuclear research or multiple purpose reactors is a common route to produce {sup 99}Mo-{sup 99m}Tc radioisotopes. Nevertheless, since the imposed limits to use LEU uranium to prevent nuclear armament production, the amount of uranium loaded in target meats has physically increased and new processes have been proposed for production. Routes using metallic uranium thin film and UAl{sub x} dispersion have been used for this purpose. Both routes have their own issues, either by bringing difficulties to disassemble the aluminum case inside hot cells or by generating great amount of alkaline radioactive liquid rejects. A potential route might be the dispersion of powders of LEU metallic uranium and nickel, which are pressed as a blend inside a die and followed by pulse electroplating of nickel. The electroplating provides more strength to the briquettes and creates a barrier for gas evolution during neutronic disintegration of {sup 235}U. A target briquette platted with nickel encapsulated in an aluminum case to be irradiated may be an alternative possibility to replace other proposed targets. This work uses pulse Ni-electroplating over iron powder briquette to simulate the covering of uranium by nickel. The following parameters were applied 10 times for each sample: 900Hz, -0.84A/square centimeters with duty cycle of 0.1 in Watts Bath. It also presented the optical microscopy analysis of plated microstructure section. (author)

  5. Uranium briquettes for irradiation target

    International Nuclear Information System (INIS)

    Saliba-Silva, Adonis Marcelo; Garcia, Rafael Henrique Lazzari; Martins, Ilson Carlos; Carvalho, Elita Fontenele Urano de; Durazzo, Michelangelo

    2011-01-01

    Direct irradiation on targets inside nuclear research or multiple purpose reactors is a common route to produce 99 Mo- 99m Tc radioisotopes. Nevertheless, since the imposed limits to use LEU uranium to prevent nuclear armament production, the amount of uranium loaded in target meats has physically increased and new processes have been proposed for production. Routes using metallic uranium thin film and UAl x dispersion have been used for this purpose. Both routes have their own issues, either by bringing difficulties to disassemble the aluminum case inside hot cells or by generating great amount of alkaline radioactive liquid rejects. A potential route might be the dispersion of powders of LEU metallic uranium and nickel, which are pressed as a blend inside a die and followed by pulse electroplating of nickel. The electroplating provides more strength to the briquettes and creates a barrier for gas evolution during neutronic disintegration of 235 U. A target briquette platted with nickel encapsulated in an aluminum case to be irradiated may be an alternative possibility to replace other proposed targets. This work uses pulse Ni-electroplating over iron powder briquette to simulate the covering of uranium by nickel. The following parameters were applied 10 times for each sample: 900Hz, -0.84A/square centimeters with duty cycle of 0.1 in Watts Bath. It also presented the optical microscopy analysis of plated microstructure section. (author)

  6. Measurement of Branching Fractions and Search for CP-violating Charge Asymmetries in Charmless Two-body B Decays into Pions and Kaons

    Energy Technology Data Exchange (ETDEWEB)

    Dallapiccola, Carlo

    2001-07-25

    We present measurements of the branching fractions and a search for CP-violating charge asymmetries in charmless hadronic decays of B mesons into two-body final states of kaons and pions. The results are based on a data sample of approximately 23 million BB(bar) pairs collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC.

  7. Pallet irradiators for food processing

    International Nuclear Information System (INIS)

    McKinnon, R.G.; Chu, R.D.H.

    1985-01-01

    This paper looks at the various design concepts for the irradiation processing of food products, with particular emphasis on handling the products on pallets. Pallets appear to offer the most attractive method for handling foods from many considerations. Products are transported on pallets. Warehouse space is commonly designed for pallet storage and, if products are already palletized before and after irradiation, then labour could be saved by irradiating on pallets. This is also an advantage for equipment operation since a larger carrier volume means lower operation speeds. Different pallet irradiator design concepts are examined and their suitability for several applications are discussed. For example, low product holdup for fast turn around will be a consideration for those operating an irradiation 'service' business; others may require a very large source where efficiency is the primary requirement and this will not be consistent with low holdup. The radiation performance characteristics and processing costs of these machines are discussed. (author)

  8. Probing nuclear correlations with pion-nucleus double charge exchange

    International Nuclear Information System (INIS)

    Ginocchio, J.N.

    1988-01-01

    In this paper we have calculated the lowest order pion double charge reaction mechanism using shell model wavefunctions of medium weight nuclei. We have the sequential reaction mechanism in which the pion undergoes two single-charge exchange scatterings on the valence neutrons. The distortion of the incoming, intermediate, and outgoing pion are included. The closure approximation is made for the intermediate states with an average excitation energy used in the pion propagator. The double-charge exchange is assumed to take place on the valence nucleons which are assumed to be in one spherical shell model orbital. 34 refs., 5 figs., 3 tabs

  9. Container for gaseous samples for irradiation at accelerators

    International Nuclear Information System (INIS)

    Kupsch, H.; Riemenschneider, J.; Leonhardt, J.

    1985-01-01

    The invention concerns a container for gaseous samples for the irradiation at accelerators especially to generate short-lived radioisotopes. The container is also suitable for storage and transport of the target gas and can be multiply reused

  10. Design and simulation of the nuSTORM pion beamline

    Energy Technology Data Exchange (ETDEWEB)

    Liu, A., E-mail: aoliu@fnal.gov; Neuffer, D.; Bross, A.

    2015-11-21

    The nuSTORM (neutrinos from STORed Muons) proposal presents a detailed design for a neutrino facility based on a muon storage ring, with muon decay in the production straight section of the ring providing well defined neutrino beams. The facility includes a primary high-energy proton beam line, a target station with pion production and collection, and a pion beamline for pion transportation and injection into a muon decay ring. The nuSTORM design uses “stochastic injection”, in which pions are directed by a chicane, referred to as the Orbit Combination Section (OCS), into the production straight section of the storage ring. Pions that decay within that straight section provide muons within the circulating acceptance of the ring. The design enables injection without kickers or a separate pion decay transport line. The beam line that the pions traverse before being extracted from the decay ring is referred to as the pion beamline. This paper describes the design and simulation of the pion beamline, and includes full beam dynamics simulations of the system.

  11. Modified three-pole VMD model with two-branch-point analytic structure and approved asymptotic behaviour for the pion electromagnetic form factor

    International Nuclear Information System (INIS)

    Dubnicka, S.; Furdik, I.; Meshcheryakov, V.A.

    1987-01-01

    A modification of three-pole VMD model for electromagnetic pion form factor was carried out, first by means of its transformation into the pion c.m. momentum variable and subsequently by using the inverse Zhukovsky transformation into another variable. In such a procedure a common normalized factor for all three vector mesons, ρ(770), ρ'(1250) and ρ''(1600), is singled out, by means of which it is possible to settle a specific freedom in the choice of the pion form factor asymptotic behaviour. An explicit incorporation of nonzero vector meson widths creates a real analytic model, defined on the four-sheeted Riemann surface. It includes inelastic contributions effectively, depends just on the parameters with a clear physical meaning, conserves the normalization of the original VMD parametrization, and provides a perfect fit of all existing pion form factor data, in which all parameters of the model are determined and the presence of ρ'(1250) in e + e - → π + π - is again established

  12. Prospects for food irradiation

    International Nuclear Information System (INIS)

    Kilcast, David

    1990-01-01

    Recent legislation will permit the introduction of food irradiation in the UK. This development has been met with protests from consumer groups, and some wariness among retailers. David Kilcast, of the Leatherhead Food Research Association, explains the basic principles and applications of food irradiation, and argues that a test marketing campaign should be initiated. The consumer, he says, will have the final say in the matter. (author)

  13. Proton irradiated graphite grades for a long baseline neutrino facility experiment

    International Nuclear Information System (INIS)

    Simos, N.; Nocera, P.; Zwaska, R.; Mokhov, N.

    2017-01-01

    In search of a low-Z pion production target for the Long Baseline Neutrino Facility (LBNF) of the Deep Underground Neutrino Experiment (DUNE) four graphite grades were irradiated with protons in the energy range of 140–180 MeV, to peak fluence of ~6.1×10"2"0 p/cm"2 and irradiation temperatures between 120–200 °C. The test array included POCO ZXF-5Q, Toyo-Tanso IG 430, Carbone-Lorraine 2020 and SGL R7650 grades of graphite. Irradiation was performed at the Brookhaven Linear Isotope Producer. Postirradiation analyses were performed with the objective of (a) comparing their response under the postulated irradiation conditions to guide a graphite grade selection for use as a pion target and (b) understanding changes in physical and mechanical properties as well as microstructure that occurred as a result of the achieved fluence and in particular at this low-temperature regime where pion graphite targets are expected to operate. A further goal of the postirradiation evaluation was to establish a proton-neutron correlation damage on graphite that will allow for the use of a wealth of available neutron-based damage data in proton-based studies and applications. Macroscopic postirradiation analyses as well as energy dispersive x-ray diffraction of 200 KeV x rays at the NSLS synchrotron of Brookhaven National Laboratory were employed. The macroscopic analyses revealed differences in the physical and strength properties of the four grades with behavior however under proton irradiation that qualitatively agrees with that reported for graphite under neutrons for the same low temperature regime and in particular the increase of thermal expansion, strength and Young’s modulus. The proton fluence level of ~10"2"0 cm"-"2 where strength reaches a maximum before it begins to decrease at higher fluences has been identified and it agrees with neutron-induced changes. X-ray diffraction analyses of the proton irradiated graphite revealed for the first time the similarity in

  14. Proton irradiated graphite grades for a long baseline neutrino facility experiment

    Science.gov (United States)

    Simos, N.; Nocera, P.; Zhong, Z.; Zwaska, R.; Mokhov, N.; Misek, J.; Ammigan, K.; Hurh, P.; Kotsina, Z.

    2017-07-01

    In search of a low-Z pion production target for the Long Baseline Neutrino Facility (LBNF) of the Deep Underground Neutrino Experiment (DUNE) four graphite grades were irradiated with protons in the energy range of 140-180 MeV, to peak fluence of ˜6.1 ×1020 p /cm2 and irradiation temperatures between 120 - 200 °C . The test array included POCO ZXF-5Q, Toyo-Tanso IG 430, Carbone-Lorraine 2020 and SGL R7650 grades of graphite. Irradiation was performed at the Brookhaven Linear Isotope Producer. Postirradiation analyses were performed with the objective of (a) comparing their response under the postulated irradiation conditions to guide a graphite grade selection for use as a pion target and (b) understanding changes in physical and mechanical properties as well as microstructure that occurred as a result of the achieved fluence and in particular at this low-temperature regime where pion graphite targets are expected to operate. A further goal of the postirradiation evaluation was to establish a proton-neutron correlation damage on graphite that will allow for the use of a wealth of available neutron-based damage data in proton-based studies and applications. Macroscopic postirradiation analyses as well as energy dispersive x-ray diffraction of 200 KeV x rays at the NSLS synchrotron of Brookhaven National Laboratory were employed. The macroscopic analyses revealed differences in the physical and strength properties of the four grades with behavior however under proton irradiation that qualitatively agrees with that reported for graphite under neutrons for the same low temperature regime and in particular the increase of thermal expansion, strength and Young's modulus. The proton fluence level of ˜1020 cm-2 where strength reaches a maximum before it begins to decrease at higher fluences has been identified and it agrees with neutron-induced changes. X-ray diffraction analyses of the proton irradiated graphite revealed for the first time the similarity in

  15. Executing Medical Guidelines on the Web: Towards Next Generation Healthcare

    Science.gov (United States)

    Argüello, M.; Des, J.; Fernandez-Prieto, M. J.; Perez, R.; Paniagua, H.

    There is still a lack of full integration between current Electronic Health Records (EHRs) and medical guidelines that encapsulate evidence-based medicine. Thus, general practitioners (GPs) and specialised physicians still have to read document-based medical guidelines and decide among various options for managing common non-life-threatening conditions where the selection of the most appropriate therapeutic option for each individual patient can be a difficult task. This paper presents a simulation framework and computational test-bed, called V.A.F. Framework, for supporting simulations of clinical situations that boosted the integration between Health Level Seven (HL7) and Semantic Web technologies (OWL, SWRL, and OWL-S) to achieve content layer interoperability between online clinical cases and medical guidelines, and therefore, it proves that higher integration between EHRs and evidence-based medicine can be accomplished which could lead to a next generation of healthcare systems that provide more support to physicians and increase patients' safety.

  16. Low-energy linac structure for PIGMI

    International Nuclear Information System (INIS)

    Swenson, D.A.; Stovall, J.E.

    1977-01-01

    The higher radio frequency (450 MHz) and lower injection energy (250 keV) of the PIGMI (Pion Generator for Medical Irradiations) linac design seriously compound the problem of beam containment in the first few meters of the structure. The conventional quadrupole-focused, drift-tube linac represents the best solution for beam energies above 8 MeV, but because of the small space available for quadrupoles in the PIGMI designs, cannot provide the required focusing at lower energies. A satisfactory solution to this focusing problem has been found based on pure alternating phase focusing for the first few MeV, followed by a smooth transition to a pure permanent magnet quadrupole-focused structure at 8 MeV. The structure and its calculated performance are described

  17. Measurement of the analyzing power for pion-proton elastic scattering between 471 and 687 MeV/c

    International Nuclear Information System (INIS)

    Mokhtari-Amirmajdi, A.

    1984-01-01

    The analyzing power, A/sub N/, has been measured for π/sup +/-/p → π/sup +/-/p at 471, 547, 625, and 687 MeV/c in an angular range corresponding to -0.9 less than or equal to cos(theta)/sub cm/ less than or equal to 0.8. A polarized proton target with polarization axis normal to the scattering plane was used. The scattered pion and recoil proton were detected in coincidence, using a magnetic spectrometer and a wire chamber/scintillator array, except in cases where one of the particles was kinematically inaccessible. Statistical uncertainties in the data are as low as 0.02; systematic uncertainties are estimated to be less than 5%. The π - p data are characterized by large values of analyzing power, and rapid variations in the angular distribution with incident momentum. The measurements are compared with the results of existing partical wave analysis

  18. Final-state interaction in spin asymmetry and GDH sum rule for incoherent pion production on the deuteron

    International Nuclear Information System (INIS)

    Darwish, E.M.; Arenhoevel, H.; Schwamb, M.

    2003-01-01

    The contribution of incoherent single-pion photoproduction to the spin response of the deuteron, i.e., the asymmetry of the total photoabsorption cross-section with respect to parallel and antiparallel spins of photon and deuteron, is calculated over the region of the Δ-resonance with inclusion of final-state NN and πN rescattering. Sizeable effects, mainly from NN rescattering, are found leading to an appreciable reduction of the spin asymmetry. Furthermore, the contribution to the Gerasimov-Drell-Hearn integral is explicitly evaluated by integration up to a photon energy of 550 MeV. Final-state interaction reduces the value of the integral to about half of the value obtained for the pure impulse approximation. (orig.)

  19. On the problem of bound states of pions and neutrons

    International Nuclear Information System (INIS)

    Gudima, K.K.; Karnaukhov, V.A.

    1992-01-01

    The problem of existence of the bound states of negative pions and neutrons has been widely discussed for the last years. It is considered possibilities of the experimental observation of pion-neutron clusters, if they do exist, in nucleus-nucleus collisions. The yields of exotic fragments π -Z n A in the interactions of 12 C and 56 Fe with 208 Pb at the energies from 0.3 to 3.7 GeV per nucleon are calculated. For 40 Ar+ 238 U and 139 La+ 238 U collisions the calculations were performed at the energied of 1.8 GeV and 1.3 GeV per nucleon, respectively. These calculations were performed in the framework of the coalescence mechanism with the differential cross sections for pion and neutron production generated by firestreak model. The differential cross sections for production of π -1 n -2 , π -2 N 2 , π - n 4 , π -4 n 6 , and π -12 n 6 were calculated. It is shown that the use of very heavy projectiles like 56 Fe and 139 La has a great advantage in the experimental search for the exotic clusters. 20 refs.; 8 figs

  20. Pion correlations in relativistic heavy ion collisions at Heavy Ion Spectrometer Systems (HISS)

    Energy Technology Data Exchange (ETDEWEB)

    Christie, W.B. Jr.

    1990-05-01

    This thesis contains the setup, analysis and results of experiment E684H Multi-Pion Correlations in Relativistic Heavy Ion Collisions''. The goals of the original proposal were: (1) To initiate the use of the HISS facility in the study of central Relativistic Heavy Ion Collisions (RHIC). (2) To perform a second generation experiment for the detailed study of the pion source in RHIC. The first generation experiments, implied by the second goal above, refer to pion correlation studies which the Riverside group had performed at the LBL streamer chamber. The major advantage offered by moving the pion correlation studies to HISS is that, being an electronic detector system, as opposed to the Streamer Chamber which is a visual detector, one can greatly increase the statistics for a study of this sort. An additional advantage is that once one has written the necessary detector and physics analysis code to do a particular type of study, the study may be extended to investigate the systematics, with much less effort and in a relatively short time. This paper discusses the Physics motivation for this experiment, the experimental setup and detectors used, the pion correlation analysis, the results, and the conclusions possible future directions for pion studies at HISS. If one is not interested in all the details of the experiment, I believe that by reading the sections on intensity interferometry, the section the fitting of the correlation function and the systematic corrections applied, and the results section, one will get a fairly complete synopsis of the experiment.

  1. Distribution of microorganisms in medical devices and their inactivation effects by gamma-irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Ishigaki, Isao

    1986-01-01

    Radiation treatment is getting important position for sterilizing medical devices and for packaging films of foods. Recently, survey of bioburden is an important technique for evaluation of sterility doses for medical devices. However, many studies have been done mainly on the irradiation effects of spore-forming bacteria in medical devices. In this study, radiation sensitivity of spore-forming bacteria and fungi were examined after the survey on distribution of microorganisms in several kinds of medical devices. The main contaminant in disposable syringes, needles and conical flasks were consisted of Bacillus, with lesser amount of Micrococcus, Pseudomonas, Peptococcaceae and fungi as positive of 5 - 60 % in the medical devices which cultivated in thioglycolate broth. Bacillus group were identified as B. pumilus, B. sphaericus, B. coagulans, B. megaterium and etc. Fungi were isolated a lesser amounts compared with spore-forming bacteria and identified as Blastomyces, Penicillium, Haplosporangium, Euricoa and Audeobasidium. Peptococaceae were not isolated after irradiation with a dose of 0.1 Mrad even the samples were contaminated with high percentage. The D 10 values of dryed endospores of Bacillus-isolates which attached to the filter paper with pepton-glycerin were obtained to be 0.11 - 0.19 Mrad. The D 10 values of many isolates of fungi in dry condition were obtained below 0.08 Mrad. However, the isolate of Aureobasidium is radiation-resistant, and it's D 10 values was obtained as 0.28 Mrad under aerobic and anaerobic dry condition. (author)

  2. In situ and ex situ characterization of the ion-irradiation effects in third generation SiC fibers

    International Nuclear Information System (INIS)

    Huguet-Garcia, Juan

    2015-01-01

    The use of third generation SiC fibers, Tyranno SA3 (TSA3) and Hi Nicalon S (HNS), as reinforcement for ceramic composites for nuclear applications requires the characterization of its structural stability and mechanical behavior under irradiation. Regarding the radiation stability, ion-amorphization kinetics of these fibers have been studied and compared to the model material, i.e. 6H-SiC single crystals, with no significant differences. For all samples, full amorphization threshold dose yields ∼0.4 dpa at room temperature and complete amorphization was not achieved for irradiation temperatures over 200 C. Successively, ion-amorphized samples have been thermally annealed. It is reported that thermal annealing at high temperatures not only induces the recrystallization of the ion-amorphized samples but also causes unrecoverable mechanical failure, i.e. cracking and delamination. Cracking is reported to be a thermally driven phenomenon characterized by activation energy of 1.05 eV. Regarding the mechanical irradiation behavior, irradiation creep of TSA3 fibers has been investigated using a tensile device dedicated to in situ tests coupled to two different ion-irradiation lines. It is reported that ion irradiation (12 MeV C 4+ and 92 MeV Xe 23+ ) induces a time-dependent strain under loads where thermal creep is negligible. In addition, irradiation strain is reported to be higher at low irradiation temperatures due to a coupling between irradiation swelling and irradiation creep. At high temperatures, near 1000 C, irradiation swelling is minimized hence allowing the characterization of the irradiation creep. Irradiation creep rate is characterized by a linear correlation between the ion flux and the strain rate and a square root dependence with the applied load. Finally, it has been reported that the higher the electronic energy loss contribution to the stopping regime the higher the irradiation creep of the fiber. (author) [fr

  3. Long-pulse applications of pulse-forming lines for high-power linac application

    International Nuclear Information System (INIS)

    Hoeberling, R.F.; Tallerico, P.J.

    1981-01-01

    The ever present demands for high efficiency in the RF power stations for particle accelerators have caused increased interest in longer RF pulses (ten's of microseconds) for linacs such as the Pion Generator for Medical Irradiation (PIGMI) and Free Electron Laser (FEL). For either RF power station, a fundamental decision is whether to use a modulating anode/hard-tube driver or pulsed cathode/line-type pulser configuration. The choices in the extremes of low power for very long pulses or for very-high-power, short pulses are, respectively, a modulated anode/hard tube modulator and pulsed cathode/pulse forming line. However, the demarcation between these two extremes is not clearcut. The criteria (cost, flexibility performance, reliability, efficiency) that resulted in the RF station definition of these two specific systems will be described

  4. Nuclear structure studies with pions and light ions: Progress report for the period June 1, 1984-May 31, 1987

    International Nuclear Information System (INIS)

    Dehnhard, D.

    1986-11-01

    Pion and proton scattering experiments were done on a variety of nuclei at the Los Alamos Meson Physics Facility. The data were used to test nuclear structure models and models of the pion-nucleus interaction, as well as assumptions about the basic nucleon-nucleon interaction. Included in this report are descriptions of completed work, work in progress, and a list of publications. 63 refs., 24 figs., 1 tab

  5. Measurement of the charged-pion polarizability.

    Science.gov (United States)

    Adolph, C; Akhunzyanov, R; Alexeev, M G; Alexeev, G D; Amoroso, A; Andrieux, V; Anosov, V; Austregesilo, A; Badełek, B; Balestra, F; Barth, J; Baum, G; Beck, R; Bedfer, Y; Berlin, A; Bernhard, J; Bicker, K; Bieling, J; Birsa, R; Bisplinghoff, J; Bodlak, M; Boer, M; Bordalo, P; Bradamante, F; Braun, C; Bressan, A; Büchele, M; Burtin, E; Capozza, L; Chiosso, M; Chung, S U; Cicuttin, A; Colantoni, M; Crespo, M L; Curiel, Q; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Dinkelbach, A M; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Dziewiecki, M; Efremov, A; Elia, C; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Geyer, R; Gnesi, I; Gobbo, B; Goertz, S; Gorzellik, M; Grabmüller, S; Grasso, A; Grube, B; Grussenmeyer, T; Guskov, A; Guthörl, T; Haas, F; von Harrach, D; Hahne, D; Hashimoto, R; Heinsius, F H; Herrmann, F; Hinterberger, F; Höppner, Ch; Horikawa, N; d'Hose, N; Huber, S; Ishimoto, S; Ivanov, A; Ivanshin, Yu; Iwata, T; Jahn, R; Jary, V; Jasinski, P; Jörg, P; Joosten, R; Kabuss, E; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O; Krämer, M; Kroumchtein, Z V; Kuchinski, N; Kuhn, R; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levillain, M; Levorato, S; Lichtenstadt, J; Maggiora, A; Magnon, A; Makke, N; Mallot, G K; Marchand, C; Martin, A; Marzec, J; Matousek, J; Matsuda, H; Matsuda, T; Meshcheryakov, G; Meyer, W; Michigami, T; Mikhailov, Yu V; Miyachi, Y; Moinester, M A; Nagaytsev, A; Nagel, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Novy, J; Nowak, W-D; Nunes, A S; Olshevsky, A G; Orlov, I; Ostrick, M; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Peshekhonov, D; Platchkov, S; Pochodzalla, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Ramos, S; Regali, C; Reicherz, G; Rocco, E; Rossiyskaya, N S; Ryabchikov, D I; Rychter, A; Samoylenko, V D; Sandacz, A; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmidt, K; Schmieden, H; Schönning, K; Schopferer, S; Schott, M; Shevchenko, O Yu; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Sosio, S; Sozzi, F; Srnka, A; Steiger, L; Stolarski, M; Sulc, M; Sulej, R; Suzuki, H; Szabelski, A; Szameitat, T; Sznajder, P; Takekawa, S; ter Wolbeek, J; Tessaro, S; Tessarotto, F; Thibaud, F; Uhl, S; Uman, I; Virius, M; Wang, L; Weisrock, T; Wilfert, M; Windmolders, R; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Ziembicki, M; Zink, A

    2015-02-13

    The COMPASS collaboration at CERN has investigated pion Compton scattering, π(-)γ→π(-)γ, at center-of-mass energy below 3.5 pion masses. The process is embedded in the reaction π(-)Ni→π(-)γNi, which is initiated by 190 GeV pions impinging on a nickel target. The exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, Q(2)<0.0015  (GeV/c)(2). From a sample of 63,000 events, the pion electric polarizability is determined to be α(π)=(2.0±0.6(stat)±0.7(syst))×10(-4)  fm(3) under the assumption α(π)=-β(π), which relates the electric and magnetic dipole polarizabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambiguously known, was performed for an independent estimate of the systematic uncertainty.

  6. Two-pion correlations in heavy ion collisions

    International Nuclear Information System (INIS)

    Zajc, W.A.

    1982-08-01

    An application of intensity interferometry to relativistic heavy ion collisions is reported. Specifically, the correlation between two like-charged pions is used to study the reactions Ar+KCl→2π/sup +-/+X and Ne+NaF→2π - +X. Source sizes are obtained that are consistent with a simple geometric interpretation. Lifetimes are less well determined but are indicative of a faster pion production process than predicted by Monte Carlo cascade calculations. There appears to be a substantial coherent component of the pion source, although measurement is complicated by the presence of final state interactions. Additionally, the generation of spectra of uncorrelated events is discussed. In particular, the influence of the correlation function on the background spectrum is analyzed, and a prescription for removal of this influence is given. A formulation to describe the statistical errors in the background is also presented. Finally, drawing from the available literature, a self-contained introduction to Bose-Einstein correlations and the Hanbury-Brown - Twiss effect is provided, with an emphasis on points of contact between classical and quantum mechanical descriptions

  7. Medications (for IBS)

    Medline Plus

    Full Text Available ... July 2017 Print Jump to Topic Medications for IBS Laxatives Anticholinergic/Antispasmodic Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, ...

  8. Process and apparatus for irradiating film, and irradiated film

    International Nuclear Information System (INIS)

    1981-01-01

    A process for irradiating film is described, which consists of passing the film through an electron irradiation zone having an electron reflection surface disposed behind and generally parallel to the film; and disposing within the irradiation zone adjacent the edges of the film a lateral reflection member for reflecting the electrons toward the reflection surface to further reflect the reflected electrons towards the adjacent edges of the film. (author)

  9. Irradiation's potential for preserving food

    International Nuclear Information System (INIS)

    Morrison, R.M.

    1986-01-01

    The first experimental studies on the use of ionizing radiation for the preservation of foods were published over thirty years ago (1, 2) . After a period of high expectations and perhaps exaggerated optimism a series of disappointments occurred in the late '60s .The first company specifically created to operate a food irradiation plant, Newfield Products Inc, ran into financial difficulties and had to close its potato irradiation facility in 1966. The irradiator, designed to process 15,000t of potatoes per month for inhibition of sprouting, was in operation during one season only. In 1968 the US Food an Drug Administration refused approval for radiation-sterilisation of ham and withdrew the approval it had granted in 1963 for irradiated bacon. An International Project on the Irradiation of Fruit and Fruit juices, created in 1965 at Seibersdorf, Austria, with the collaboration or 9 countries, ended with general disappointment after three years. The first commercial grain irradiator, built in the Turkish harbour town of Iskenderun by the International Atomic Energy Agency with funds from the United Nations Development Program, never received the necessary operating licence from the Turkish Government and had to be dismantled in 1968. The US Atomic Energy Commission terminated its financial support to all research programmes on food irradiation in 1970. For a number of years, little chance seemed to remain that the new process would ever be practically used. However, research and development work was continued in a number of laboratories all over the world, and it appears that the temporary setbacks now have been overcome. Growing quantities of irradiated foods are being marketed in several countries and indications are that irradiated foods will eventually be as generally accepted as are frozen, dried or heatsterilised foods

  10. Phenotype and molecular analysis of M1 generation of stylosanthes irradiated by 60Co

    International Nuclear Information System (INIS)

    Zhang Weili; Liu Fengmin

    2012-01-01

    The seeds of Stylosanthes guianensis SW. ‘Reyan No.13’ were irradiated by 60 Co at 0, 325, 487 and 974 Gy. Phenotype and molecular variations of Stylosanthes M 1 generations were studied. Germination percentage, plant height, leaf length and stem diameter of M 1 seedlings were determined using SRAP-PCR. Results showed that biological character indices of treatments were significantly lower than that of control (CK). Irradiation inhibited plant growth. Growth indices of 974 Gy treatment, except leaf length, were significantly lower than CK and other two treatments. Eight effective primers selected from 24 primers combination were used for SRAP-PCR. SRAP analysis revealed that the 57 of 88 DNA fragments were amplified showing polymorphisms. The average percentage of polymorphic bands was 64.77%. The effects of 60 Coγ irradiation on DNA variation of seedlings were varied from different treatments. Numbers of polymorphic bands changed after irradiation. Coefficient of variation was in direct proportion to irradiation doses. Variation rates of 325 Gy, 487 Gy and 974 Gy treatments were 22.0%, 38.1% and 41.5%, respectively. The Nei’s genetic similarity coefficient of all treatments was ranged from 0.585 to 0.780 by software NTSYSpc 2.1 based on SRAP results and the average Nei's coefficient was 0.678. The Nei’s genetic similarity coefficient of 974 Gy treatment was 0.585 and variation degree was highest among all treatments, 487 Gy treatment was second and 325 Gy treatment was the lowest one. Based on present bands, four irradiated treatments were classified into two major groups by UPGMA cluster analysis. Group 1 included CK, 325 Gy and 487 Gy treatment and group 2 included 974 Gy. SRAP analysis determined variation of Stylosanthes after irradiation and the results of SRAP analysis were consistent with their biological indexes in some extent

  11. Medical irradiation, radioactive waste and misinformation. A press release from the French Academy of Medicine; Irradiation medicale, dechets, desinformation: un avis de l'Academie de medecine

    Energy Technology Data Exchange (ETDEWEB)

    The, G. de; Tubiana, M

    2002-07-01

    The Academy of Medicine, worried by the problems that poses for public opinion the medical irradiation, the radioactive wastes and some erroneous information that these subjects give rise to, considers useful to give an advice based on objective data. (N.C.)

  12. Gamma irradiators for radiation processing

    International Nuclear Information System (INIS)

    2006-01-01

    Radiation technology is one of the most important fields which the IAEA supports and promotes, and has several programmes that facilitate its use in the developing Member States. In view of this mandate, this Booklet on 'Gamma Irradiators for Radiation Processing' is prepared which describes variety of gamma irradiators that can be used for radiation processing applications. It is intended to present description of general principles of design and operation of the gamma irradiators available currently for industrial use. It aims at providing information to industrial end users to familiarise them with the technology, with the hope that the information contained here would assist them in selecting the most optimum irradiator for their needs. Correct selection affects not only the ease of operation but also yields higher efficiency, and thus improved economy. The Booklet is also intended for promoting radiation processing in general to governments and general public

  13. Irradiation probe and laboratory for irradiated material evaluation

    International Nuclear Information System (INIS)

    Smutny, S.; Kupca, L.; Beno, P.; Stubna, M.; Mrva, V.; Chmelo, P.

    1975-09-01

    The survey and assessment are given of the tasks carried out in the years 1971 to 1975 within the development of methods for structural materials irradiation and of a probe for the irradiation thereof in the A-1 reactor. The programme and implementation of laboratory tests of the irradiation probe are described. In the actual reactor irradiation, the pulse tube length between the pressure governor and the irradiation probe is approximately 20 m, the diameter is 2.2 mm. Temperature reaches 800 degC while the pressure control system operates at 20 degC. The laboratory tests (carried out at 20 degC) showed that the response time of the pressure control system to a stepwise pressure change in the irradiation probe from 0 to 22 at. is 0.5 s. Pressure changes were also studied in the irradiation probe and in the entire system resulting from temperature changes in the irradiation probe. Temperature distribution in the body of the irradiation probe heating furnace was determined. (B.S.)

  14. Medical irradiation and the use of the ''effective dose equivalent'' concept

    International Nuclear Information System (INIS)

    Persson, B.R.R.

    1980-01-01

    The aim of this paper is to demonstrate the use of the effective dose for all kinds of medical irradiation. In order to estimate the 'somatic effective dose' the weighting factors recommended by ICRP 26 have been separated into those for somatic effects and for genetic effects. Calculation of the effective dose in diagnostic radiology procedures must consider the various technical parameters which determine the absorbed dose in the various organs, i.e. beam quality, typical entrance dose and the number of films of each view. Knowledge about these parameters is not always well established and therefore the effective dose estimates are very uncertain. The average dose absorbed by various organs in the case of administration of radionuclides to the body depends to a much higher degree on biological parameters than in the case of external irradiation. In contrast to the variability and lack of reliability of biological data, the physical methods for internal dose calculation are quite elaborate. However, these methods have to be extended to involve the target dose from the radioactivity distributed within the remaining parts of the body. An attempt was made to estimate the somatic effective dose for the most common diagnostic X-ray and nuclear medicine procedures. This would make it possible to compare the risk of X-ray and nuclear medicine techniques on a more equitable basis. The collective effective dose from medical irradiation is estimated for various countries on the basis of reported statistical data. (H.K.)

  15. Near-threshold charged pion photoproduction from 13C

    International Nuclear Information System (INIS)

    LeRose, J.J.

    1981-01-01

    Differential cross sections to discrete final states have been measured for both positive and negative pion photo-production on 13 C at 90 0 in the lab at pion energies of 18, 29, and 41 MeV. Measurements were made using a fixed angle magnetic spectrometer located in the 14 0 area of the MIT Bates linear accelerator. Pions were detected using a 90 channel multi-wire proportional counter in the focal plane along with a backup array consisting of three 1/16'' thick plastic scintillator detectors and a 1/2'' thick Cerenkov detector. Positive pion photo-production cross sections were obtained for the excitation of the 3/2 - ground state and for the 3.45 MeV first excited state of 13 B. Negative pion photo-production cross sections were obtained for the excitation of the 1/2 - ground state, and the 3/2 to 3.51 MeV and 5/2 to 7.39 MeV excited states of 13 N. The measured positive pion photo-production ground state cross sections are in reasonable agreement wth theoretical calculations. However, there is a large discrepancy between the measured negative pion photoproduction ground state cross sections and the theoretical values. There are no theoretical calculations available for comparison with the excited state measurements in either positive or negative pion photoproduction on 13 C

  16. Streamer chamber: pion decay

    CERN Multimedia

    1992-01-01

    The real particles produced in the decay of a positive pion can be seen in this image from a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. A magnetic field is added to cause the decay products to follow curved paths so that their charge and momentum can be measured.

  17. Pion production experiments at IUCF

    Science.gov (United States)

    Daehnick, W. W.

    2001-12-01

    Pion production in pp collisions is of special interest near threshold where very few partial waves contribute and where calculations should be manageable and results more conclusive. The first explicit calculations for pp → ppπ0 and pp → pnπ+ cross sections near threshold were made by Koltun and Reitan in 1966 and by Schillaci, Silbar and Young in 1969. They remained unchallenged and untested until cross sections very close to threshold could finally be measured1,2. The realization that the pioneering calculations missed the true cross sections by a wide margin has spurred much new theoretical research.3,4,5 ...

  18. Long-term results of high-dose conformal radiotherapy for patients with medically inoperable T1-3N0 non-small-cell lung cancer: Is low incidence of regional failure due to incidental nodal irradiation?

    International Nuclear Information System (INIS)

    Chen Ming; Hayman, James A.; Haken, Randall K. ten; Tatro, Daniel; Fernando, Shaneli; Kong, F.-M.

    2006-01-01

    Purpose: To report the results of high-dose conformal irradiation and examine incidental nodal irradiation and nodal failure in patients with inoperable early-stage non-small-cell lung cancer (NSCLC). Methods and Materials: This analysis included patients with inoperable CT-staged T1-3N0M0 NSCLC treated on our prospective dose-escalation trial. Patients were treated with radiation alone (total dose, 63-102.9 Gy in 2.1-Gy daily fractions) with a three-dimensional conformal technique without intentional nodal irradiation. Bilateral highest mediastinal and upper/lower paratracheal, prevascular and retrotracheal, sub- and para-aortic, subcarinal, paraesophageal, and ipsilateral hilar regions were delineated individually. Nodal failure and doses of incidental irradiation were studied. Results: The potential median follow-up was 104 months. For patients who completed protocol treatment, median survival was 31 months. The actuarial overall survival rate was 86%, 61%, 43%, and 21% and the cause-specific survival rate was 89%, 70%, 53%, and 35% at 1, 2, 3, and 5 years, respectively. Weight loss (p = 0.008) and radiation dose in Gy (p = 0.013) were significantly associated with overall survival. In only 22% and 13% of patients examined did ipsilateral hilar and paratracheal (and subaortic for left-sided tumor) nodal regions receive a dose of ≥40 Gy, respectively. Less than 10% of all other nodal regions received a dose of ≥40 Gy. No patients failed initially at nodal sites. Conclusions: Radiation dose is positively associated with overall survival in patients with medically inoperable T1-3N0 NSCLC, though long-term results remain poor. The nodal failure rate is low and does not seem to be due to high-dose incidental irradiation

  19. Pion production in high energy heavy ion collisions

    International Nuclear Information System (INIS)

    Wolf, K.L.; Bock, R.; Brockmann, R.

    1984-01-01

    Experimental data for heavy ion pion production reactions are compared with the predictions of a number of versions of cascade models. Pion suppression effects observed in the experimental data are fit by introducing refinements into cascade theory. Impact parameter adjustment, off-shell effects on the potential and perturbations due to nuclear matter are considered

  20. Pion correlation from Skyrmion--anti-Skyrmion annihilation

    International Nuclear Information System (INIS)

    Lu, Y.; Amado, R.D.

    1995-01-01

    We study two pion correlations from Skyrmion and anti-Skyrmion collision, using the product ansatz and an approximate random grooming method for nucleon projection. The spatial-isospin coupling inherent in the Skyrme model, along with empirical averages, leads to correlations not only among pions of like charges but also among unlike charge types

  1. Generation and composition of medical wastes from private medical microbiology laboratories.

    Science.gov (United States)

    Komilis, Dimitrios; Makroleivaditis, Nikolaos; Nikolakopoulou, Eftychia

    2017-03-01

    A study on the generation rate and the composition of solid medical wastes (MW) produced by private medical microbiology laboratories (PMML) was conducted in Greece. The novelty of the work is that no such information exists in the literature for this type of laboratories worldwide. Seven laboratories were selected with capacities that ranged from 8 to 88 examinees per day. The study lasted 6months and daily recording of MW weights was done over 30days during that period. The rates were correlated to the number of examinees, examinations and personnel. Results indicated that on average 35% of the total MW was hazardous (infectious) medical wastes (IFMW). The IFMW generation rates ranged from 11.5 to 32.5g examinee -1 d -1 while an average value from all 7 labs was 19.6±9.6g examinee -1 d -1 or 2.27±1.11g examination -1 d -1 . The average urban type medical waste generation rate was 44.2±32.5g examinee -1 d -1 . Using basic regression modeling, it was shown that the number of examinees and examinations can be predictors of the IFMW generation, but not of the urban type MW generation. The number of examinations was a better predictor of the MW amounts than the number of examinees. Statistical comparison of the means of the 7PMML was done with standard ANOVA techniques after checking the normality of the data and after doing the appropriate transformations. Based on the results of this work, it is approximated that 580 tonnes of infectious MW are generated annually by the PMML in Greece. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Experimental studies of pion-nucleus interactions at intermediate energies

    International Nuclear Information System (INIS)

    1991-01-01

    This report summarizes the work on experimental research in intermediate energy nuclear physics carried out at New Mexico State University in 1991 under a great from the US Department of Energy. Most of these studies have involved investigations of various pion-nucleus interactions. The work has been carried out both with the LAMPF accelerator at the Los Alamos National Laboratory and with the cyclotron at the Paul Scherrer Institute (PSI) near Zurich, Switzerland. Part of the experimental work involves measurements of new data on double-charge-exchange scattering, using facilities at LAMPF which we helped modify, and on pion absorption, using a new detector system at PSI that covers nearly the full solid-angle region which we helped construct. Other work involved preparation for future experiments using polarized nuclear targets and a new high-resolution spectrometer system for detecting π 0 mesons. We also presented several proposals for works to be done in future years, involving studies related to pi-mesonic atoms, fundamental pion-nucleon interactions, studies of the difference between charged and neutral pion interactions with the nucleon, studies of the isospin structure of pion-nucleus interactions, and pion scattering from polarized 3 He targets. This work is aimed at improving our understanding of the pion-nucleon interaction, of the pion-nucleus interaction mechanism, and of nuclear structure

  3. Pion-nucleon vertex function and the Chew-Low model

    International Nuclear Information System (INIS)

    Nutt, W.T.

    1977-01-01

    We provide an interpretation of the cutoff function used in the Chew-Low theory of pion-nucleon scattering. It is shown that this function may be related to the pion-pion interaction which is not explicitly considered in the Chew-Low approach. Using a previously developed model for the pion-nucleon vertex function, we then perform a ''parameter-free'' Chew-Low calculation which predicts the P 33 resonance quite well

  4. Charge dependence of the pion-nucleon coupling constant

    Directory of Open Access Journals (Sweden)

    V. A. Babenko

    2015-07-01

    Full Text Available On the basis of the Yukawa potential we study the pion-nucleon coupling constants for the neutral and charged pions assuming that nuclear forces at low energies are mainly determined by the exchange of virtual pions. We obtain the charged pseudovector pion-nucleon coupling constant f2π± = 0.0804(7 by making the use of experimental low-energy scattering parameters for the singlet pp- and np-scattering, and also by use of the neutral pseudovector pion-nucleon coupling constant f2π0 = 0.0749(7. Corresponding value of the charged pseudoscalar pion-nucleon coupling constant g2π0 / 4π = 14.55(13 is also determined. This calculated value of the charged pseudoscalar pion-nucleon coupling constant is in fully agreement with the experimental constant g2π0 / 4π = 14.52(26 obtained by the Uppsala Neutron Research Group. Our results show considerable charge splitting of the pion-nucleon coupling constant.

  5. Paternity after irradiation for testicular cancer

    International Nuclear Information System (INIS)

    Fossa, S.D.; Almaas, B.; Jetne, V.; Bjerkedal, T.; Norske Radiumhospital, Oslo. Dept. of Medical Physics; Norwegian Council for Science and the Humanities, Oslo)

    1986-01-01

    According to the Medical Birth Registry (MBR) of Norway, 69 of about 430 patients irradiated for testicular cancer (stage I+II) during 1966-1978 fathered at least one child after radiation therapy (median observation time 136 months, range 36-191 months). A total of 95 children were born. Between 10 and 122 months elapsed between discontinuation of irradiation and the birth of the first child born after radiation therapy. Though the total doses to the abdominal irradiation field were higher in patients irradiated by a linear accelerator (1971-1978), than in those treated by a betatron (1966-1970), the gonadal doses were generally lower in the former group due to better gonadal shielding. In the children, the sex ratio and the median weight and length at birth were comparable to those values seen in a control group from the MBR. No increased frequency of malformations was observed. It is concluded that modern radiation therapy techniques allow post-irradiation fathership in a significant number of patients without risk of neonatal problems or malformations in the children. (orig.)

  6. Numerology on pion and proton rapidity

    International Nuclear Information System (INIS)

    Gugelot, P.C.

    1987-01-01

    The pseudo-rapidity of pion jets which were measured for 50 GeV and 150 GeV incident pions and protons on carbon, copper and lead targets is analysed. The shape of the rapidity distribution for a ''fireball'' which emits particles isotropically in its center of mass is a cosh -2 y distribution. It is possible to unfold all measured distributions into three groups which correspond to a low rapidity originating from the target fragmentation, a middle group which is a function of the center of mass of the projectile and target rapidity and a fast group which is due to the projectile. 11 refs., 8 figs. (author)

  7. Pion-induced damage in silicon detectors

    CERN Document Server

    Bates, S; Glaser, M; Lemeilleur, F; León-Florián, E; Gössling, C; Kaiser, B; Rolf, A; Wunstorf, R; Feick, H; Fretwurst, E; Lindström, G; Moll, Michael; Taylor, G; Chilingarov, A G

    1995-01-01

    The damage induced by pions in silicon detectors is studied for positive and negative pions for fluence up to 10(14)cm-2 and 10(13) cm-2 respectively. Results on the energy dependence of the damage in the region of 65-330 MeV near to the  resonance are presented. The change in detector characteristics such as leakage current, charge collection efficiency and effective impurity concentration including long-term annealing effects have been studied. Comparisons to neutron and proton-induced damage are presented and discussed.

  8. [Requirements for final year medical studies in the era of generation Y - implementation for general and visceral surgery at the Ludwig Maximilians University of Munich].

    Science.gov (United States)

    Albertsmeier, M; Pratschke, S; Raes, P; Werner, J; Angele, M K

    2014-12-01

    The revision of the medical licensing regulations in 2012 has changed the underlying conditions for the practical year (PY), especially in the sense of markedly more flexibility for the medical students. The driving force for these and future changes, however, is not the legislature but rather the students themselves who are explicitly demanding that their training be adapted to their requirements and wishes. Time for the realisation of personal aims, planning of leisure time activities, for the family and social contacts as well as an altogether balanced work-life balance have replaced the wish for professional advancement as premise for the lifestyle of generation Y. Many hospitals, especially the privately-supported, attract students with special offers - university hospitals are called upon to defend their position in the competition for newly qualified students. The present article describes the changes of 2012 as part of a programme for a sustainable increase in the attractivity of the surgical PY at the Ludwig-Maximilian University (LMU) in Munich. Georg Thieme Verlag KG Stuttgart · New York.

  9. The Nonlinear Effects of Pion-Quark Coupling in the Cloudy Bag Model

    OpenAIRE

    Yasuhiko, FUTAMI; Satoru, AKIYAMA; Department of Physics, Faculty of Science and Technology Science University of Tokyo; Department of Physics, Faculty of Science and Technology Science University of Tokyo

    1990-01-01

    The nonlinear pion-quark interaction in the Cloudy Bag Model is investigated. The Hamiltonian is normal-ordered. The vacuum expectation value of pion field squared is evaluated by introducting some cutoff momentum for the virtual pions.We then calculate g_A, including other corrections.

  10. The nonlinear effects of pion-quark coupling in the Cloudy Bag Model

    International Nuclear Information System (INIS)

    Futami, Yasuhiko; Akiyama, Satoru

    1990-01-01

    The nonlinear pion-quark interaction in the Cloudy Bag Model is investigated. The Hamiltonian is normal-ordered. The vacuum expectation value of pion field squared is evaluated by introducing some cutoff momentum for the virtual pions. We then calculate g A , including other corrections. (author)

  11. Effects of the pion string at heavy ion collisions

    International Nuclear Information System (INIS)

    Mao Hong; Li Yunde; East China Normal Univ., Shanghai

    2005-01-01

    The authors study the possible signals of the pion string associated with the QCD chiral phase transition in LHC Pb-Pb collision at energy √s=5.5 TeV. The authors follow the Kibble-Zurek mechanism to discuss the production and evolution of the pion string. The authors will show that if the QCD chiral phase transition really takes place in the LHC Pb-Pb collision process and the phase transition is in the second order, the pion string will be inevitably produced and subsequently decay. The main effect of this phenomenon is that there is a generation of a large number of pions in the final state produced by the decay of the pion string, and these pions are mostly distributed in a low momentum region with p-143 MeV; also there are lots of neutral pions distributed in a low momentum region with the mean momentum at p-21 MeV. (authors)

  12. analysis of the measured medical waste generation at amana

    African Journals Online (AJOL)

    kagonji

    2011-08-16

    Aug 16, 2011 ... In this study the medical waste generation rates at Amana and Ligula hospitals ...... making the situation difficult to administrators to plan and budget. ..... Management Meeting, Peacock Hotel, Dar es Salaam, 9th-11th June,.

  13. Quantum signature in heavy-ion pion production

    International Nuclear Information System (INIS)

    Buvel, R.L.

    1985-01-01

    A revised model for pion production in heavy-ion peripheral collisions is presented. The pion-production mechanism investigated here is a two step process involving the formation and subsequent decay of an isobar resonance in the projectile nucleus. The independent-particle shell model with harmonic oscillator states is used to approximate the internal structure of the nucleus. The inclusion of the internal structure of the projectile nucleus led to the discovery of a quantum signature in the pion-production differential cross section. The quantum signature involves a matching condition where the pion-production differential cross section goes to zero for a particular value of the pion kinetic energy. The theory is compared to a recent experiment, but the results of this comparison are inconclusive

  14. A beam detector for pion experiments and analysis of the inclusive Λ production in proton-proton reactions with HADES

    Energy Technology Data Exchange (ETDEWEB)

    Lalik, Rafal Tomasz

    2016-06-02

    This thesis presents the work focused on two topics related to the physics performed at the HADES detector. In the first part, the development of the tracking detector playing an important role of online beam monitoring and the momentum reconstruction device in the secondary pion beam experiment is presented. Such a detector must fulfill various requirements regarding the operation in the vacuum, with accelerator beams and high count rates. Two detection stations employing double sided silicons strip sensors with an active area of 10 cm x 10 cm and position resolution of 780 μm, providing momentum resolution below 0.5 % and capable for operating with beams up to 32 x 10{sup 6} particles/s total and 2 x 10{sup 6} particles/s in a single channel have been constructed, tested and used in the pion beam experiments. In the first chapter, general information about the production of the secondary, in particular, pion beams is presented. Further, description how the momentum is reconstructed using the information obtained from the tracking detector, and description of most important components of the system, namely the silicon sensor and front end electronics used for its readout is presented. In the second chapter, development of the detector, including all the components used or constructed for this particular purpose is presented. This section also includes description of the laboratory tests and calibrations performed to characterize the detector. In the end of the section, results from two of the beam runs employed for the tests of the detector are presented and discussed. The last third chapter presents results from the commissioning of the tracking detector in the final configuration. Momentum reconstruction feasibility is presented. The second part of the thesis focuses on the analysis of inclusive production of the Λ hyperons in the nuclear reactions at the HADES energies. The aims of the analysis are to extract the differential cross-section of Λ production in

  15. On the changing petroleum generation properties of Alum Shale over geological time caused by uranium irradiation

    Science.gov (United States)

    Yang, Shengyu; Schulz, Hans-Martin; Horsfield, Brian; Schovsbo, Niels H.; Noah, Mareike; Panova, Elena; Rothe, Heike; Hahne, Knut

    2018-05-01

    An interdisciplinary study was carried out to unravel organic-inorganic interactions caused by the radiogenic decay of uranium in the immature organic-rich Alum Shale (Middle Cambrian-Lower Ordovician). Based on pyrolysis experiments, uranium content is positively correlated with the gas-oil ratios and the aromaticities of both the free hydrocarbons residing in the rock and the pyrolysis products from its kerogen, indicating that irradiation has had a strong influence on organic matter composition overall and hence on petroleum potential. The Fourier Transform Ion Cyclotron Resonance mass spectrometry data reveal that macro-molecules in the uranium-rich Alum Shale samples are less alkylated than less irradiated counterparts, providing further evidence for structural alteration by α-particle bombardment. In addition, oxygen containing-compounds are enriched in the uranium-rich samples but are not easily degradable into low-molecular-weight products due to irradiation-induced crosslinking. Irradiation has induced changes in organic matter composition throughout the shale's entire ca. 500 Ma history, irrespective of thermal history. This factor has to be taken into account when reconstructing petroleum generation history. The Alum Shale's kerogen underwent catagenesis in the main petroleum kitchen area 420-340 Ma bp. Our calculations suggest the kerogen was much more aliphatic and oil-prone after deposition than that after extensive exposure to radiation. In addition, the gas sorption capacity of the organic matter in the Alum Shale can be assumed to have been less developed during Palaeozoic times, in contrast to results gained by sorption experiments performed at the present day, for the same reason. The kerogen reconstruction method developed here precludes overestimations of gas generation and gas retention in the Alum Shale by taking irradiation exposure into account and can thus significantly mitigate charge risk when applied in the explorations for both

  16. Proton- and x-ray beams generated by ultra-fast CO2 lasers for medical applications

    Science.gov (United States)

    Pogorelsky, Igor; Polyanskiy, Mikhail; Yakimenko, Vitaly; Ben-Zvi, Ilan; Shkolnikov, Peter; Najmudin, Zulfikar; Palmer, Charlotte A. J.; Dover, Nicholas P.; Oliva, Piernicola; Carpinelli, Massimo

    2011-05-01

    Recent progress in using picosecond CO2 lasers for Thomson scattering and ion-acceleration experiments underlines their potentials for enabling secondary radiation- and particle- sources. These experiments capitalize on certain advantages of long-wavelength CO2 lasers, such as higher number of photons per energy unit, and favorable scaling of the electrons' ponderomotive energy and critical plasma density. The high-flux x-ray bursts produced by Thomson scattering of the CO2 laser off a counter-propagating electron beam enabled high-contrast, time-resolved imaging of biological objects in the picosecond time frame. In different experiments, the laser, focused on a hydrogen jet, generated monoenergetic proton beams via the radiation-pressure mechanism. The strong power-scaling of this regime promises realization of proton beams suitable for laser-driven proton cancer therapy after upgrading the CO2 laser to sub-PW peak power. This planned improvement includes optimizing the 10-μm ultra-short pulse generation, assuring higher amplification in the CO2 gas under combined isotopic- and power-broadening effects, and shortening the postamplification pulse to a few laser cycles (150-200 fs) via chirping and compression. These developments will move us closer to practical applications of ultra-fast CO2 lasers in medicine and other areas.

  17. Shihoro irradiation plant for potato

    International Nuclear Information System (INIS)

    Kameyama, Kenji

    1985-01-01

    There have been rapid moves toward the commercialization of food irradiation around the world since November, 1980, when a joint FAO/IAEA/WHO expert committee made a recommendation on the wholesomeness of irradiated foods. The bold US move toward the commercialization has had a great impact. Ahead of these move around the world, Japan built a commercial irradiation plant in 1974, which has been operated for inhibiting the sprouting of potatoes. This plant was built in Shihoro, Hokkaido, and two thirds of the 400 million yen construction cost was provided by the Government and Hokkaido authorities for five agricultural cooperative associations of four local townships. Since then, the plant has been under the joint management of these cooperatives. The aim and circumstance of the plant construction are described. The mechanism of the plant with conveyors, a turntable and a Co-60 source of 300,000 Ci is shown. The plant processes 15 tons of potatoes per hour with the dose from 60 to 150 Gy. Potato bruise and irradiation effect, irradiation time and effect, and post-irradiation storage temperature and potato quality are reported. (Kako, I.)

  18. Identification methods for irradiated wheat

    International Nuclear Information System (INIS)

    Zhu Shengtao; Kume, Tamikazu; Ishigaki, Isao.

    1992-02-01

    The effect of irradiation on wheat seeds was examined using various kinds of analytical methods for the identification of irradiated seeds. In germination test, the growth of sprouts was markedly inhibited at 500Gy, which was not affected by storage. The decrease in germination percentage was detected at 3300Gy. The results of enzymatic activity change in the germ measured by Vita-Scope germinator showed that the seeds irradiated at 10kGy could be identified. The content of amino acids in ungerminated and germinated seeds were analyzed. Irradiation at 10kGy caused the decrease of lysine content but the change was small which need very careful operation to detect it. The chemiluminescence intensity increased with radiation dose and decreased during storage. The wheat irradiated at 10kGy could be identified even after 3 months storage. In the electron spin resonance (ESR) spectrum analysis, the signal intensity with the g value f 2.0055 of skinned wheat seeds increased with radiation dose. Among these methods, germination test was the most sensitive and effective for identification of irradiated wheat. (author)

  19. Spectator-velocity pions from heavy ions

    International Nuclear Information System (INIS)

    Rasmussen, J.; Ridout, J.; Murphy, D.; Radi, H.M.A.

    1982-11-01

    The discussion centers on pions in the velocity regions of target and projectile, where strong spectral features appear. The topics covered include stopped-pion studies, and convoy pions in the projectile frame

  20. Design of small-animal thermal neutron irradiation facility at the Brookhaven Medical Research Reactor

    International Nuclear Information System (INIS)

    Liu, H.B.

    1996-01-01

    The broad beam facility (BBF) at the Brookhaven Medical Research Reactor (BMRR) can provide a thermal neutron beam with flux intensity and quality comparable to the beam currently used for research on neutron capture therapy using cell-culture and small-animal irradiations. Monte Carlo computations were made, first, to compare with the dosimetric measurements at the existing BBF and, second, to calculate the neutron and gamma fluxes and doses expected at the proposed BBF. Multiple cell cultures or small animals could be irradiated simultaneously at the so-modified BBF under conditions similar to or better than those individual animals irradiated at the existing thermal neutron irradiation Facility (TNIF) of the BMRR. The flux intensity of the collimated thermal neutron beam at the proposed BBF would be 1.7 x 10 10 n/cm 2 ·s at 3-MW reactor power, the same as at the TNIF. However, the proposed collimated beam would have much lower gamma (0.89 x 10 -11 cGy·cm 2 /n th ) and fast neutron (0.58 x 10 -11 cGy·cm 2 /n th ) contaminations, 64 and 19% of those at the TNIF, respectively. The feasibility of remodeling the facility is discussed

  1. Effective pion--nucleon interaction in nuclear matter

    International Nuclear Information System (INIS)

    Celenza, L.S.; Liu, L.C.; Nutt, W.; Shakin, C.M.

    1976-01-01

    We discuss the modification of the interaction between a pion and a nucleon in the presence of an infinite medium of nucleons (nuclear matter). The theory presented here is covariant and is relevant to the calculation of the pion--nucleus optical potential. The specific effects considered are the modifications of the nucleon propagator due to the Pauli principle and the modification of the pion and nucleon propagators due to collisions with nucleons of the medium. We also discuss in detail the pion self-energy in the medium, paying close attention to off-shell effects. These latter effects are particularly important because of the rapid variation with energy of the fundamental pion--nucleon interaction. Numerical results are presented, the main feature being the appearance of a significant damping width for the (3, 3) resonance

  2. Soliton bag model of the nucleon and delta dressed by a quark-antiquark pion

    International Nuclear Information System (INIS)

    Dethier, J.L.L.

    1985-01-01

    The Friedberg-Lee soliton bag model is used to describe the nucleon, delta and pion. The author builds upon the mean-field solutions to the model taking into account the one-gluon-exchange interaction by the use of a free gluon propagator in the Coulomb gauge and allowing the nucleon or delta to consist of a bare three quark bag and a three quark bag dressed by one quark-antiquark pion. This way of treating the pion cloud differs from most other works on the subject by the fact that he takes the quark substructure of the pion into account. The generator coordinate method enables him to find an approximate solution to the ground state of the nucleon and the delta from which static physical properties can be calculated. The soliton field part of the ground state is treated in a coherent state approximation (similar to the mean-field approximation, but remaining a true quantum state). The generator coordinate or Hill-Wheeler integral equations are solved numerically with the help of the Tikhonov regularization. Detailed numerical results are given for different sets of parameters. The agreement with experiment is as good as in the mean-field approximation but new quantities are now accessible to computation (e.g., the neutron charge radius and the NN[ and NΔπ coupling constants

  3. Electron beam irradiation on cation exchanger used for strontium recovery

    International Nuclear Information System (INIS)

    Watanabe, Sou; Nakamura, Masahiro; Nomura, Kazunori; Nakajima, Yasuo; Okamoto, Yoshihiro

    2014-01-01

    Titanate is promising material for radioactive Sr recovery from liquid waste generated in the nuclear facilities. "9"0Sr is one of the most important nuclides in order to release the liquid waste into the environment due to its strong beta-ray decay energy. Although the titanate is applied to radioactive Sr decontamination facility, their resistance to irradiations from radioactive elements adsorbed is not widely investigated so far. In this study, durability of a hydrous titanic acid ion exchanger against beta-ray irradiation were evaluated through electron beam irradiation, elution behaviour of Sr after the irradiation and local structural analysis of the titanate. 1.4 MGy irradiation led to 1% of Sr elution, and the elution could be attributed to defects of O in the titanate induced by the irradiation. Chemical state of Ti of the titanate must be stable up to 2.7 MGy irradiation. (author)

  4. Generation and validation of a prognostic score to predict outcome after re-irradiation of recurrent glioma

    Energy Technology Data Exchange (ETDEWEB)

    Combs, Stephanie E.; Welzel, Thomas; Debus, Juergen [Univ. Hospital of Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany)], E-mail: Stephanie.combs@med.uni-heidelberg.de; Edler, Lutz; Rausch, Renate [German Cancer Research Center (dkfz), Dept. of Biostatistics, Heidelberg (Germany); Wick, Wolfgang [Univ. Hospital of Heidelberg, Dept. of Neurooncology, Heidelberg (Germany)

    2013-01-15

    Re-irradiation using high-precision radiation techniques has been established within the clinical routine for patients with recurrent gliomas. In the present work, we developed a practical prognostic score to predict survival outcome after re-irradiation. Patients and methods. Fractionated stereotactic radiotherapy (FSRT) was applied in 233 patients. Primary histology included glioblastoma (n = 89; 38%), WHO Grade III gliomas (n = 52; 22%) and low-grade glioma (n = 92; 40%). FSRT was applied with a median dose of 36 Gy in 2 Gy single fractions. We evaluated survival after re-irradiation as well as progression-free survival after re-irradiation; prognostic factors analyzed included age, tumor volume at re-irradiation, histology, time between initial radiotherapy and re-irradiation, age and Karnofsky Performance Score. Results. Median survival after FSRT was 8 months for glioblastoma, 20 months for anaplastic gliomas, and 24 months for recurrent low-grade patients. The strongest prognostic factors significantly impacting survival after re-irradiation were histology (p <0.0001) and age (<50 vs. ={>=}50, p < 0.0001) at diagnosis and the time between initial radiotherapy and re-irradiation {<=}12 vs. >12 months (p < 0.0001). We generated a four-class prognostic score to distinguish patients with excellent (0 points), good (1 point), moderate (2 points) and poor (3-4 points) survival after re-irradiation. The difference in outcome was highly significant (p < 0.0001). Conclusion. We generated a practical prognostic score index based on three clinically relevant factors to predict the benefit of patients from re-irradiation. This score index can be helpful in patient counseling, and for the design of further clinical trials. However, individual treatment decisions may include other patient-related factors not directly influencing outcome.

  5. Electromagnetic form factors for nucleons and pions at positive and negative q2 in the model of quark-gluon strings

    International Nuclear Information System (INIS)

    Kaidalov, A.B.; Kondratyuk, L.A.; Tchekin, D.V.

    2000-01-01

    The electromagnetic form factors for pions and nucleons are considered within the model of quark-gluon strings, where the momentum-transfer dependence of hadronic form factors is determined by the intercepts of the corresponding Regge trajectories and by the Sudakov form factor. Analytic expressions found for form factors in the timelike region admit an analytic continuation to the spacelike region. The resulting form factors for pions and nucleons comply well with experimental data both for positive and for negative values of the squared momentum transfer q 2 . It is shown that the distinctions between the absolute values of the pion and nucleon form factors F π (q 2 ), G m (q 2 ), and F 2 (q 2 ) at positive values of q 2 and those at negative values of this variable are associated with the analytic properties of the double-logarithmic term in the exponent of the Sudakov form factor. The spin structure of the amplitudes for quark transitions into hadrons that is proposed in the present study makes it possible to describe fairly well available experimental data on the Pauli form factor F 2 and on the ratio G e /G m

  6. Proposal for an experiment at the SIN: contribution on πE3-beam dosimetry. Measurement of particle spectra after pion absorption in biologically interesting nuclei

    International Nuclear Information System (INIS)

    Appel, H.; Boehmer, V.; Bueche, G.; Kluge, W.; Matthay, H.

    It is proposed to measure the energy spectra of light charged particles (protons, deuterons, tritons, 3 He- and 4 He-nuclei) and of neutrons, after the absorption of stopped pions in the biologically interesting hydrogen, oxygen, carbon, and nitrogen nuclei. In addition, the relative particle yield will be examined in tissue-like targets such as polyethylene, plexiglas, and water. Furthermore, it is proposed to measure the coincidence spectra of two particles emitted after absorption, as a function of the angle between their impulses. In the case of a pure three-body decay, these examinations may open the possibility of drawing conclusions about the heavy recoil nuclei arising during pion absorption. Particle energy and type will be determined by a combined time-of-flight/energy measurement with totally absorbent NaI or plastic detectors. The HF signal will serve as a start signal for time-of-flight measurements

  7. On correlation comparison of identical pions in different systems of reference

    International Nuclear Information System (INIS)

    Podgoretskij, M.I.

    1983-01-01

    It is shown that a comparison of correlations of identical pions in reference frames moving with different velocities along the reaction axis enables one to select the frame for which there is a kinematical symmetry in the multiple generation process. The indicated possibility is due to the fact that in the considered symmetrical frame the space-time parameters R and tau are extremal. An experimental selection of the ''symmetrical frame'' may be useful in the choice between competing models of multiple generation

  8. Optimization of the pion beam for the HADES detector and determination of the η form factor in proton-proton reactions at 2.2 GeV

    International Nuclear Information System (INIS)

    Spruck, Bjoern

    2008-01-01

    This thesis contains two tasks. The first part focuses on the development and optimization of the pion beam facility for the HADES experiment. The second part describes the measurement of the electromagnetic transition form factor of the η meson in proton-proton reactions. To investigate pion-nucleon reaction, a secondary pion beam is required. The pions are produced by a heavy ion beam impinging on a beryllium target. In order to determine the profile of the beam focus, two scintillating fiber detectors have been built as part of this thesis and are read out with recently developed electronics. The measured size of the beam focus appeared to be not acceptable, which can be attributed to the achromatic magnetic focusing in the beam line. Simulations have shown, that an additional quadrupole magnet directly in front of HADES would solve this problem and improve the beam quality. A test experiment including this new quadrupole has been performed and the analysis is still in progress. Preliminary results show a significant reduction of the momentum dependency of the focus. The size of the actual beam spot has been deduced to 14 mm by using an indirect tracking approach. For deducing the electromagnetic structure of hadrons, a first step has been done by analyzing the η Dalitz decay in p+p reactions at 2.2 GeV kinetic energy to determine the electromagnetic transition form factor of the η meson. A fit to the data leads to a form factor slope of b=2.2 -1.4 +1.2 GeV -2 . This corresponds to a pole mass of λ=680 -130 +460 MeV/c 2 . It has been shown, that a semi-exclusive analysis of the η Dalitz decay within the event hypothesis framework including a kinematical fit is feasible. (orig.)

  9. Generation and management of medical waste in Serbia: A review

    Directory of Open Access Journals (Sweden)

    Šerović Radmila M.

    2016-01-01

    Full Text Available This study presents generation, quantities and medical waste (MW management in Serbia. It represents assessment methods and total annual MW generation by categories. It was concluded that pharmaceutical (64% and infectious (32% MW production is the largest. According to available data, MW management in Serbia is currently at low level, except when it comes to infectious waste. Research proposed simpler treatment methods in existing autoclaves and complex methods (incineration and plasma-pyrolysis, as well as short-term and long-term solutions. Predicted MW growing amount requires existing capacity increase for processing and new solutions application. Installed autoclaves capacity could be increased by increasing working time, in order to avoid additional investment. However, treatment in autoclave is only suitable for infectious MW. For other medical waste, which main fractions are pharmaceutical and chemical waste, there is no infrastructure. As temporary solution, pharmaceutical waste is treated abroad which in longer period is not financially feasible. Considering that MW treatment in Serbia currently is based on health facilities network equipped with autoclaves, as central (CTF and local (LTF treatments facilities for infectious waste treatment, it is recommended additional capacity implementation for treatment of non-infectious waste to this network, with simultaneous management level optimization of whole MW.

  10. EPR spectra induced by gamma-irradiation of some dry medical herbs

    Science.gov (United States)

    Yordanov, N. D.; Lagunov, O.; Dimov, K.

    2009-04-01

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050±0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show "cellulose-like" EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050±0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the "cellulose-like" EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as "carbohydrate-like" type. Only one intense EPR singlet with g=2.0048±0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months.

  11. EPR spectra induced by gamma-irradiation of some dry medical herbs

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Lagunov, O.; Dimov, K.

    2009-01-01

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050±0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show 'cellulose-like' EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050±0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the 'cellulose-like' EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as 'carbohydrate-like' type. Only one intense EPR singlet with g=2.0048±0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months

  12. EPR spectra induced by gamma-irradiation of some dry medical herbs

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)], E-mail: ndyepr@bas.bg; Lagunov, O. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Dimov, K. [Institute of Cryobiology and Food technology, 1162 Sofia (Bulgaria)

    2009-04-15

    The radiation-induced EPR spectra in some medical herbs are reported. The samples studied are: (i) leaves of nettle, common balm, peppermint and thyme; (ii) stalks of common balm, thyme, milfoil, yarrow and marigold; (iii) blossoms of yarrow and marigold; (iv) blossoms and leaves of hawthorn and tutsan; and (v) roots of common valerian, nettle, elecampane (black and white), restharrows and carlina. Before irradiation all samples exhibit one weak anisotropic singlet EPR line with effective g-value of 2.0050{+-}0.0002. The radiation-induced spectra fall into three groups. EPR spectra of irradiated blossoms of yarrow and marigold, stalks of common balm, thyme, tutsan and yarrow as well as roots of common valerian, nettle and elecampane (black and white) show 'cellulose-like' EPR spectrum typical for irradiated plants. It is characterized by one intense central line with g=2.0050{+-}0.0005 and two weak satellite lines situated ca. 30 G left and right to it. EPR spectra of gamma-irradiated restharrows and carlina are complex. They may be represented by one triplet corresponding to the 'cellulose-like' EPR spectrum, one relatively intense singlet, situated in the center of the spectrum, and five weak additional satellite lines left and right to the center. The last spectrum was assigned as 'carbohydrate-like' type. Only one intense EPR singlet with g=2.0048{+-}0.0005 was recorded after irradiation of leaves of nettle and common balm. The lifetime of the radiation-induced EPR spectra was followed for a period of 3 months.

  13. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Drews, J.; Leipold, Frank

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N2/O2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can...

  14. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    International Nuclear Information System (INIS)

    Kusano, Y; Drews, J; Leipold, F; Fateev, A; Bardenshtein, A; Krebs, N

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N 2 /O 2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can enhance ozone production especially when the DBD was driven at a frequency of 15 kHz.

  15. Generation of polyyne and methylpolyyne molecules from toluene by intense femtosecond laser pulse irradiation

    International Nuclear Information System (INIS)

    Ramadhan, Ali; Wesolowski, Michal; Duley, Walter; Sanderson, Joseph; Wakabayashi, Tomonari; Shiromaru, Haruo; Fujino, Tatsuya; Kodama, Takeshi

    2015-01-01

    Hydrogen-capped and methyl-capped carbon chains (polyynes) have been generated by intense femtosecond laser irradiation of pure liquid toluene. UV-Vis and Raman spectroscopy were used to confirm the presence of polyynes in the irradiated samples, and high performance liquid chromatography (HPLC) was used to separate polyynes up to C 18 H 2 and HC 13 CH 3 . (paper)

  16. Measurement of Branching Fractions for Two-Body Charmless B Decays to Charged Pions and Kaons at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, Barbara

    2000-08-28

    The authors present preliminary results of a search for charmless two-body B decays to charged pions and kaons using data collected by the BaBar detector at the Stanford Linear Accelerator Center's PEP-II Storage ring. In a sample of 8.8 million produced B anti-B pairs the authors measure the branching fractions beta(B{sup 0} --> pi{sup +}pi{sup {minus}}) = (9.3{sub {minus}2.3{minus}1.4}{sup +2.6+1.2}) x 10{sup {minus}6} and beta(B{sup 0} --> K{sup +}pi{sup {minus}}) = (12.5{sub {minus}2.6{minus}1.7}{sup +3.0+1.3}) x 10{sup {minus}6}, where the first uncertainty is statistical and the second is systematic. For the decay B{sup 0} --> K{sup +}K{sup {minus}} they find no significant signal and set an upper limit of beta(B{sup 0} --> K{sup +}K{sup {minus}}) < 6.6 x 10{sup {minus}6} at the 90% confidence level.

  17. The Next Generation Nuclear Plant/Advanced Gas Reactor Fuel Irradiation Experiments in the Advanced Test Reactor

    International Nuclear Information System (INIS)

    Grover, S. Blaine

    2009-01-01

    The United States Department of Energy's Next Generation Nuclear Plant (NGNP) Program will be irradiating eight separate low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The ATR has a long history of irradiation testing in support of reactor development and the INL has been designated as the new United States Department of Energy's lead laboratory for nuclear energy development. The ATR is one of the world's premiere test reactors for performing long term, high flux, and/or large volume irradiation test programs. These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States, and will be irradiated over the next ten years to demonstrate and qualify new particle fuel for use in high temperature gas reactors. The goals of the irradiation experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of at least six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The first experiment (designated AGR-1) started irradiation in December 2006, and the second experiment (AGR-2) is currently in the design phase. The design of test trains, as well as the support systems and fission product monitoring system that will monitor and control the experiment during irradiation will be discussed. In

  18. Pion electromagnetic mass difference in QCD

    International Nuclear Information System (INIS)

    Margvelashvili, M.V.

    1989-01-01

    The results of currents algebra and the theory of partial conservation of axial currents the sum rules for the calculation of electromagnetic pion mass difference are developed. The procedure applied is suitable for other physical applications as it permits to calculate the integrals from different correlators with the assigned weight functions

  19. Photoproduction of neutral pions off protons

    NARCIS (Netherlands)

    Crede, V.; Sparks, N.; Wilson, A.; Anisovich, A. V.; Bacelar, J. C. S.; Bantes, R.; Bartholomy, O.; Bayadilov, D.; Beck, R.; Beloglazov, Y. A.; Castelijns, R.; Dutz, H.; Elsner, D.; Ewald, R.; Frommberger, F.; Funke, Chr; Gregor, R.; Gridnev, A.; Gutz, E.; Hillert, W.; Hoffmeister, P.; Jaegle, I.; Junkersfeld, J.; Kalinowsky, H.; Kammer, S.; Klein, Frank; Klein, Friedrich; Klempt, E.; Kotulla, M.; Krusche, B.; Löhner, H.; Lopatin, I. V.; Lugert, S.; Menze, D.; Mertens, T.; Messchendorp, J. G.; Metag, V.; Nanova, M.; Nikonov, V. A.; Novinski, D.; Novotny, R.; Ostrick, M.; Pant, L. M.; van Pee, H.; Pfeiffer, M.; Roy, A.; Sarantsev, A. V.; Schadmand, S.; Schmidt, C.; Schmieden, H.; Schoch, B.; Shende, S.; Sokhoyan, V.; Suele, A.; Sumachev, V. V.; Szczepanek, T.; Thoma, U.; Trnka, D.; Varma, R.; Walther, D.; Wendel, Ch

    2011-01-01

    Photoproduction of neutral pions has been studied with the CBELSA/TAPS detector in the reaction gamma p -> p pi(0) for photon energies between 0.85 and 2.50 GeV. The pi(0) mesons are observed in their dominant neutral decay mode: pi(0) -> gamma gamma. For the first time, the differential cross

  20. Effect of thermal friction on the generation and transport of interstitial defects in irradiated metals

    CERN Document Server

    Dudarev, S L

    2002-01-01

    Generation of interstitial and vacancy defects under 14.1 MeV neutron irradiation is expected to drive the evolution of microstructure of materials in a future fusion power station. We investigate effects of thermal friction associated with the interaction between mobile clusters of interstitial atoms produced in collision cascades and phonon excitations. Phonons give rise to the random Brownian motion of clusters in the crystal lattice. Phonon excitations are also responsible for the dissipation of energy of rapidly moving clusters formed at the periphery of collision cascades. We investigate how the coefficient of thermal friction depends on the structure of clusters. We also discuss implications of our findings for understanding the origin of higher resistance of bcc metals to irradiation and the connection between this phenomenon and the long-range effect observed in experiments on ion implantation.

  1. Effect of high altitude cosmic irradiation upon cell generation time

    International Nuclear Information System (INIS)

    Soleilhavoup, J.P.; Croute, F.; Tixador, R.; Blanquet, Y.; Planel, H.

    1975-01-01

    Paramecia cultures placed at 3800 meter altitude show a proliferating activity acceleration compared to control cultures placed at low altitude under the same environment conditions. These results confirm the cosmic irradiation influence upon the activating effect produced by the natural ionizing radiations on living organisms [fr

  2. Pion absorption in excited nuclear matter

    International Nuclear Information System (INIS)

    Schmidt, H.R.; Albrecht, R.; Bock, R.; Gutbrod, H.H.; Kolb, B.W.; Lund, I.; Awes, T.C.; Baktash, C.; Ferguson, R.L.; Lee, I.Y.; Plasil, F.; Saini, S.; Tincknell, M.; Young, G.R.; Beckmann, P.; Berger, F.; Clewing, G.; Dragon, L.; Glasow, R.; Kampert, K.H.; Peitzmann, T.; Purschke, M.; Santo, R.; Claesson, G.; Eklund, A.; Garpman, S.; Gustafsson, H.A.; Idh, J.; Oskarsson, A.; Otterlund, I.; Persson, S.; Stenlund, E.; Franz, A.; Jacobs, P.; Poskanzer, A.M.; Ritter, H.G.; Kristiansson, P.; Loehner, H.; Obenshain, F.E.; Sorensen, S.P.; Siemiarczuk, T.

    1992-02-01

    The target dependence and azimuthal correlations of protons and plons are investigated for pA reactions at 4.9, 60 and 200 GeV. The experimental observations can be understood qualitatively under the assumption that pions are absorbed in excited target spectator matter. (orig.)

  3. The spin structure of the pion

    Energy Technology Data Exchange (ETDEWEB)

    Broemmel, D. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany)]|[Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Diehl, M. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Goeckeler, M. [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)

    2007-08-15

    We present the first calculation of the transverse spin structure of the pion in lattice QCD. We find a characteristic asymmetry in the spatial distribution of transversely polarized quarks. This asymmetry is very similar in magnitude to the analogous asymmetry we previously obtained for quarks in the nucleon. Our results support the hypothesis that all Boer-Mulders functions are alike. (orig.)

  4. Pion showers in highly granular calorimeters

    Indian Academy of Sciences (India)

    New results on properties of hadron showers created by pion beam at 8–80 GeV in high granular electromagnetic and hadron calorimeters are presented. Data were used for the first time to investigate the separation of the neutral and charged hadron showers. The result is important to verify the prediction of the PFA ...

  5. Physics with low energy pions and muons

    International Nuclear Information System (INIS)

    Konijn, J.

    1981-01-01

    This document is a collection of texts used for a course of lectures given by the author at the Technical University of Delft (NL) in 1981. It is therefore a comprehensive, Dutch language, review article starting with the discovery of pions and muons, describing their properties and finally discussing their applications in low energy physics. (C.F.)

  6. Pion-pair production by two photons

    International Nuclear Information System (INIS)

    Terazawa, Hidezumi.

    1994-07-01

    The cross section for pion-pair production by two photons is calculated approximately by using the low energy theorem previously derived from partially-conserved-axial-vector-current hypothesis and current algebra, and found to agree very well with the experimental data recently obtained by the Mark II, TPC/Two-Gamma and CLEO Collaborations. (author)

  7. Pion photoproduction in nucleons at low energies

    International Nuclear Information System (INIS)

    Carvalho, F.A.B.R. de.

    1983-01-01

    A new semiphenomenological analysis of the multipoles for pion photoproduction from nucleons, in the region of the first π-N resonance is presented. Through an energy dependent model, multipoles with isospin 1/2 and 3/2 and total angular momentum J [pt

  8. Effects of pions on normal tissues

    International Nuclear Information System (INIS)

    Tokita, N.

    1981-01-01

    Verification of the uniform biological effectiveness of pion beams of various dimensions produced at LAMPF has been made using cultured mammalian cells and mouse jejunum. Normal tissue radiobiology studies at LAMPF are reviewed with regard to biological beam characterization for the therapy program and the current status of acute and late effect studies on rodents

  9. Medical irradiation risk assessment based on the data of radiation-hygienic passportization in the regions of the Russian Federation

    Directory of Open Access Journals (Sweden)

    V. Ju. Golikov

    2015-01-01

    Full Text Available This article is aimed at methodology development for collective risk assessment of medical irradiation, basing on results of radiation-hygienic passportization in the Russian Federation regions, i.e. using values of collective effective doses for big groups of medical technologies: photoroentgenography, roentgenography, roentgenoscopy, and computer tomography. Use of the effective dose concept for medical irradiation risk definition involves a number of essential restrictions. Age and sex of the employees and of general population (effective dose concept has been developed for these groups of people may essentially differ from those in patients. Lifelong risk of stochastic effects occurrence in children is 2-3 times higher than the rating values used in effective dose concept, while for elderly people (about 60 years at irradiation time it’s 4-5 times lower. The article suggests the algorithm of effective doses values correcting factors assessment for consideration of dependence of radiogenic cancer risk factors on age and sex. This enables to assess more correctly collective risk of radiology and nuclear medicine imaging. Since patients tend to be elderly and their risk factor is below the rating used in the effective dose concept, the values of these correcting factors for most radiology and nuclear medicine imaging are below one. Thus, in most cases, the effective dose concept leads to conservative assessment of medical irradiation collective risk.

  10. Safeguards approach for irradiated fuel

    International Nuclear Information System (INIS)

    Harms, N.L.; Roberts, F.P.

    1987-03-01

    IAEA verification of irradiated fuel has become more complicated because of the introduction of variations in what was once presumed to be a straightforward flow of fuel from reactors to reprocessing plants, with subsequent dissolution. These variations include fuel element disassembly and reassembly, rod consolidation, double-tiering of fuel assemblies in reactor pools, long term wet and dry storage, and use of fuel element containers. This paper reviews future patterns for the transfer and storage of irradiated LWR fuel and discusses appropriate safeguards approaches for at-reactor storage, reprocessing plant headend, independent wet storage, and independent dry storage facilities

  11. SCATPI, a subroutine for calculating πN cross sections and polarizations for incident pion kinetic energies between 90 and 300 MeV

    International Nuclear Information System (INIS)

    Walter, J.B.; Rebka, G.A. Jr.

    1979-03-01

    A subroutine, SCATPI, was written which calculates π + p elastic differential cross sections for incident pion kinetic energies between 90 and 310 MeV for π - p. The calculation is based upon the phase shift analysis of Carter, Bugg, and Carter, and is reliable to about 2% for π + p and 3% for π - p differential cross sections. SCATPI also calculates other scattering parameters for the π+-p systems. The calculations are compared with the measurements used in the phase shift analysis, and with selected recent measurements. The use of SCATPI is described. 14 figures, 4 tables

  12. A Reappraisal of the Mechanism of Pion Exchange and Its Implications for the Teaching of Particle Physics

    Science.gov (United States)

    Dunne, Peter

    2002-01-01

    The origins of the pion exchange model of nuclear forces are described and the exchange process is reinterpreted in the light of current views on the quark-gluon structure of nucleons. It is suggested that the reinterpretation might provide a picture of cohesive nuclear forces that is more intellectually satisfying than that produced by the…

  13. Internal irradiation for cystic craniopharyngioma

    International Nuclear Information System (INIS)

    Kobayashi, Tatsuya; Kageyama, Naoki

    1979-01-01

    Internal irradiation with P-32 chromic phosphate and Au-198 colloid was used to treat cystic craniopharyngioma. A newly developed dosimetric formula, by which the radiation dose can be calculated simultaneously at the cyst wall and at a point far from the radioactive source and the untoward effect of irradiation on surrounding brain tissue can be eliminated, especially in cases in which the wall is thin and can be penetrated by beta emission, was used. Radioactive phosphate or gold was injected into eight craniopharyngioma cysts throught the Ommaya reservoir and a tube inserted at the first craniotomy. All cysts were effectively treated for 3 to 33 months, to eliminate fluid retention or collapse. A collapsed cyst was removed at the second craniotomy and irradiation was histologically shown to be effective. Oculomotor palsy, a side effect of irradiation, occurred 10 days after the injection of 5 mc of P-32 chromic phosphate only in a case of small cysts (5.0 ml) in the supra- and intracellular regions. The thickness of the cyst wall was less than 0.5 mm and the oculomotor nerves were thought to adhere to the wall. Not only the amount of wall dose but also the thickness of the wall and localization of the cyst are important factors in internal irradiation. Sufficient and safer doses which kill tumor cells in the wall and have no side effects, are 9,000 to 30,000 rad. Internal irradiation can be used to treat large cysts of more than 10 ml which are supposedly difficult to remove radically and or multiple cysts. It is effective not only for cystic craniopharyngioma but also for intracrania cystic tumors other than craniopharyngioma, if dosimetry is accurate. (J.P.N.)

  14. Craniospinal Irradiation for Trilateral Retinoblastoma Following Ocular Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Marks, Lawrence B.; Bentel, Gunilla; Sherouse, George W.; Spencer, David P.; Light, Kim

    2015-01-15

    A case study is presented. Craniospinal radiotherapy and a three-field pineal boost for trilateral retinoblastoma were delivered to a patient previously irradiated for ocular retinoblastoma. The availability of CT-based three-dimensional treatment planning provided the capability of identifying the previously irradiated volume as a three-dimensional anatomic structure and of designing a highly customized set of treatment beams that minimized reirradiation of that volume.

  15. Generation and validation of a prognostic score to predict outcome after re-irradiation of recurrent glioma

    International Nuclear Information System (INIS)

    Combs, Stephanie E.; Welzel, Thomas; Debus, Juergen; Edler, Lutz; Rausch, Renate; Wick, Wolfgang

    2013-01-01

    Re-irradiation using high-precision radiation techniques has been established within the clinical routine for patients with recurrent gliomas. In the present work, we developed a practical prognostic score to predict survival outcome after re-irradiation. Patients and methods. Fractionated stereotactic radiotherapy (FSRT) was applied in 233 patients. Primary histology included glioblastoma (n = 89; 38%), WHO Grade III gliomas (n = 52; 22%) and low-grade glioma (n = 92; 40%). FSRT was applied with a median dose of 36 Gy in 2 Gy single fractions. We evaluated survival after re-irradiation as well as progression-free survival after re-irradiation; prognostic factors analyzed included age, tumor volume at re-irradiation, histology, time between initial radiotherapy and re-irradiation, age and Karnofsky Performance Score. Results. Median survival after FSRT was 8 months for glioblastoma, 20 months for anaplastic gliomas, and 24 months for recurrent low-grade patients. The strongest prognostic factors significantly impacting survival after re-irradiation were histology (p 12 months (p < 0.0001). We generated a four-class prognostic score to distinguish patients with excellent (0 points), good (1 point), moderate (2 points) and poor (3-4 points) survival after re-irradiation. The difference in outcome was highly significant (p < 0.0001). Conclusion. We generated a practical prognostic score index based on three clinically relevant factors to predict the benefit of patients from re-irradiation. This score index can be helpful in patient counseling, and for the design of further clinical trials. However, individual treatment decisions may include other patient-related factors not directly influencing outcome.

  16. New facility for post irradiation examination of neutron irradiated beryllium

    International Nuclear Information System (INIS)

    Ishitsuka, Etsuo; Kawamura, Hiroshi

    1995-01-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800 degrees C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and 60 Co;7.4 MBq/day

  17. Low energy scattering with a nontrivial pion

    International Nuclear Information System (INIS)

    Fariborz, Amir H.; Jora, Renata; Schechter, Joseph

    2007-01-01

    An earlier calculation in a generalized linear sigma model showed that the well-known current algebra formula for low energy pion-pion scattering held even though the massless Nambu Goldstone pion contained a small admixture of a two-quark two-antiquark field. Here we turn on the pion mass and note that the current algebra formula no longer holds exactly. We discuss this small deviation and also study the effects of a SU(3) symmetric quark mass type term on the masses and mixings of the eight SU(3) multiplets in the model. We calculate the s-wave scattering lengths, including the beyond current algebra theorem corrections due to the scalar mesons, and observe that the effect of the scalar mesons is to improve the agreement with experiment. In the process, we uncover the way in which linear sigma models give controlled corrections (due to the presence of scalar mesons) to the current algebra scattering formula. Such a feature is commonly thought to exist only in the nonlinear sigma model approach

  18. Technical relapsed testicular irradiation for acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Velazquez Miranda, S.; Delgado Gil, M. M.; Ortiz Siedel, M.; Munoz Carmona, D. M.; Gomez-Barcelona, J.

    2011-01-01

    Testicular irradiation in children suffering from acute lymphoblastic leukemia presents difficulties in relation to daily positioning, dosimetry for dose homogenization of complex geometry and volume change during irradiation thereof. This can lead to significant deviations from the prescribed doses. In addition, the usual techniques often associated with unnecessary irradiation of pelvic simphysis, anus and perineum. This, in the case of pediatric patients, is of great importance, since doses in the vicinity of 20 Gy are associated with a deviation of bone growth, low testosterone levels around 24 Gy and high rates of generation of second tumors. To overcome these problems we propose a special restraint in prone and non-coplanar irradiation.

  19. Anisotropy of the pion emission in relativistic nucleus-nucleus collisions

    International Nuclear Information System (INIS)

    Babinet, R.; Cavata, C.; Demoulins, M.; Fanet, H.; Gosset, J.; Lemaire, M.C.; Le Merdy, A.; L'Hote, D.; Lucas, B.; Poitou, J.; Alard, J.P.; Augerat, J.; Bastid, N.; Charmensat, P.; Dupieux, P.; Fraysse, L.; Marroncle, J.; Montarou, G.; Parizet, M.J.; Ramani, A.; Brochard, F.; Gorodetzky, P.; Racca, C.

    1990-01-01

    The production of pions and baryons from Ne and Ar induced reactions on Ca, NaF, Nb and Pb targets, in the range of .2 to 1 GeV per nucleon, is discussed. The 4π detector Diogenes at the Saturne accelerator facility is applied. The reaction plane is determined from the baryon momenta distribution and used as a reference for the pion triple differential cross-sections. A transverse momentum analysis is carried out for baryons and pions. The pion squared reduced impact parameter and the flow characteristics are given. The results show that the azimuthal anisotropy of pion emission increases with the asymmetry of the system. The evidence that pion absorption effects may be responsible for the azimuthal anisotropy of the pion emission is provided

  20. Medications (for IBS)

    Medline Plus

    Full Text Available ... Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation Techniques for IBS Take Part in Online ...